CRUISE REPORT: P16N
(Updated AUG 2015)







Highlights

                             Cruise Summary Information

               Section Designation  P16N
Expedition designation (ExpoCodes)  33RO20150525
                   Chief Scientist  Alison Macdonald/WHOI
                Co-Chief Scientist  Sabine Mecking / UW/APL
                             Dates  25 May 2015 – 27 June 2015
                              Ship  NOAAS Ronald H. Brown
                     Ports of call  Honolulu, Hawaii – Seattle, Washington

                                                   56° 47.40' N
             Geographic Boundaries  153° 20.39' W                135° 57.03' W
                                                   22° 29.96' N

                          Stations  95
      Floats and drifters deployed  5 Argo floats were deployed.
    Moorings deployed or recovered  0

                                 Contact Information:

                                 Dr. Alison Macdonald
                         Woods Hole Oceanographic Institution
               266 Woods Hole Rd. • MS# 21 • Woods Hole, MA 02543-1050
                  Tel: +1 508 289 3507 • Email: macdonald@whoi.edu

                                  Dr. Sabine Mecking
                 University of Washington, Applied Physics Laboratory
              1013 NE 40th Street • Box 355640 • Seattle, WA 98105-6698
                      Tel: 206-221-6570 • Email: mecking@uw.edu




































                           GO-SHIP CLIVAR/Carbon P16N Leg 2

                                NOAAS Ronald H. Brown
                              25 May 2015 - 27 June 2015
                       Honolulu, Hawaii - Seattle, Washington

                                   Chief Scientist:
                                 Dr. Alison Macdonald
                        Woods Hole Oceanographic Institution

                                 Co-Chief Scientist:
                                 Dr. Sabine Mecking
                            University of Washington, APL

                              Preliminary Cruise Report
                                     27 June 2015


                                CTD Data Submitted by:

                                Kristene E. McTaggart
                National Oceanic and Atmospheric Administration, PMEL
                                      Seattle, WA
                                          And
                                      James Hooper
                National Oceanic and Atmospheric Administration, AOML
                                      Miami, FL

                             Bottle Data Submitted by:

                                Courtney Schatzman
               Shipboard Technical Support/Oceanographic Data Facility
                   Scripps Institution of Oceanography/UC San Diego
                                     La Jolla, CA













Cruise Narrative


Abstract

The GO-SHIP repeat occupation of the pre-WOCE 1984, WOCE 1991 and CLIVAR 2006 
P16N/Leg 2 along 152°W between Hawaii and Kodiak Island was successfully 
completed aboard the NOAA ship Ronald H. Brown from 25 May, 2015 to 27 June, 
2015. The cruise also included a repeat of one segment of the 1993 P17N 
section. Academic institutions, NOAA research laboratories, as well as some 
NSF funded scientists and students participated in P16N/Leg 2. This project 
was one of a number of decadal reoccupations of hydrography sections jointly 
funded by NOAA-COD/CPO (Climate Observation Division of the Climate Program 
Office) and NSF-OCE (National Science Foundation Division of Ocean Sciences) 
as part of the GO-SHIP (Global Ocean Ship-Based Hydrographic Investigation 
Program) /CO2/hydrography/tracer program.

More details on the program can be found at the websites: 

     http://ushydro.ucsd.edu and www.go-ship.org/


Data from this cruise are available from CCHDO at:

     http://cchdo.ucsd.edu/data_access/show_cruise?ExpoCode=33R020150525


The informal "blog" that recounted some of the cruise highlights can be found 
at:  http://clivarpl6n2Ol5.blogspot.coml


and will also be accessible through the US Hydro website at: 

     http://ushydro.ucsd.edu/outreach1content/2O15/O4/18/pl6n-2015-blog/

The GO-SHIP Repeat Hydrography Program focuses on the need to monitor 
inventories of CO2. heat and freshwater and their transports in the ocean, 
and provides the only available high quality, multi-variable, basin-scale 
time-series of the full water column. It provides an observational framework 
to monitor long-term trends as well as decadal variability. Together with the 
results of the earlier CLIVAR, WOCE and JGOFS programs, GO-SHIP observations 
are used to assess changes in the ocean's physical and biogeochemical cycles 
through the continued re-occupation of a set of hydrographic transects with 
full water column measurements over the global ocean to support: heat, 
freshwater and carbon system studies, deep and shallow water mass and 
ventilation studies, calibration of autonomous sensors, and model calibration 
and validation.


Track

Leg 2 of the 2015 P16N transect (henceforth referred to as Leg 2), which 
started out from Honolulu, HI and ended in Seattle, WA, was the third 
component of GO-SHIP's full P16 line. P16S along 150°W, 67°S to 15°S was 
occupied spring 2014. P16N/Leg 1, occupied between 11 April and 11 May, 2015 
began just south of where P16S left off at 16.5°S, along 152°W to 22.5°N 
(P16N stations 1 to 112). Leg 2 extended the line from 22.5°N to 54.66°N 
along 152°W (P16N stations 113 to 176) before turning northwestward to cross 
perpendicular to the bathymetric contours of the Alaskan Slope onto the 
Alaska Shelf (stations 177 to 189 at 56.44°N, 153.34'W), including one 
station in the center of the Aleutian Trench (station 181 at 55.60°N, 
155.70°W, 5382m depth). Station 190 occupied the same position as station 184 
in the Alaskan Current (55.95°N, 152.98°W), but placed a focus on bottle 
samples in the deep and bottom waters. The cross-gyre section is made up of 
station 176 (56.44°N, 152°W) and stations 191 (54.07°N, 151.11°W) to 207 
(56.79°N, 135.95°W) running northeastward across the Alaskan Gulf along a 
line similar to the WOCE P17N section in 1993. Nominal stations spacing for 
Leg 2 was 30 nm (0.50 latitude) along 152°W, with closer spacing over the 
slope and shelf. The cross-gyre section used a nominal 40 nm spacing. 
Eighteen stations west of 152°W that would have provided further sampling of 
the shelf and a second crossing of the northern slope following the track of 
WOCE P17N line were planned, but removed before the cruise began due to a 
delay in the departure out of Hawaii (see below).


Bottle Sampling Program

At each of the 95 Leg 2 stations the 24-bottle rosette was sent down to 
within approximately 10 m of the bottom. At all, except the shallowest 
slope/shelf locations, all bottles were fired. At 20 of these locations, the 
rosette was sent down a second time to approximately 1000 m to collect 
samples for later cesium analysis. Again all 24 bottles were fired. Three 
rotating staggering schema each were used to fully measure the water on both 
the full water column and the thousand meter casts.

This produced a collection of 2740 water samples for analyses of a variety of 
parameters including: salinity, dissolved oxygen, nutrients (phosphate, 
silicate, nitrate and nitrite), chlorofluorocarbons (CFC5), sulfur 
hexafluoride (SF6), dissolved inorganic carbon (DIC), total alkalinity, two 
types of pH measurements, radiocarbon (DI14C, dissolved organic carbon (DOC 
and DO14C), chromophoric dissolved organic material (CDOM), particulate 
organic carbon (POC), chlorophyll, tritium, helium, black carbon, cesium 
(134Cs and 137Cs), strontium (90Sr) and iodine (129I).

The rosette also carried a CTDO system (conductivity, temperature, pressures, 
oxygen), a transmissometer, fluorometer, Under Water Vision Profiler (UVP), 
upward and downward looking Lowered Acoustic Doppler Profilers (LADCP), as 
well as a pair of upward and downward looking chi-pods. At all stations where 
cesium sampling occurred, a surface sample was also taken from the ship's 
seawater intake. At each station where CDOM sampling occurred, surface 
samples for phytoplankton pigments (HPLC) and particulate absorption spectra 
(AP) were also taken from the ship's seawater intake. Once a day, when a 
hydrographic station was occupied around midday a light profiling spectro-
radiometer was deployed. Over the course of Leg 2 these casts occurred 32 
times. Once a night, when a station occurred around midnight, bongo nets were 
deployed to collect pteropods for later analysis testing in vivo adaptation 
strategies to rising CO2 levels (29 net tows in all). Five Argo floats were 
deployed. Underway data collection included upper-ocean current measurements 
from the shipboard ADCP, surface oceanographic (temperature, salinity, 
fluorescence, chlorophyll pigments, and carbon dioxide) and meteorological 
parameters from the ship's underway systems and bathymetric data and 
atmospheric measurements.


Successes and Challenges

Prior to the P16N cruise, Leg 2 stations were categorized as being part of 
the primary objective (the 152°W reoccupation), the secondary objective (the 
Alaskan Shelf and Gyre reoccupation of some of the P17N stations) or 
supplemental (11 stations providing closer spacing on the shelves and 
slopes). During the in-port in Hawaii between legs 1 and 2, after a variety 
repair attempts, the Brown's engineers and local service personnel determined 
that one of the ship's air conditioning units required replacement. With so 
many aspects of the cruise dependent upon good air conditioning (from the z-
drive to science) it was considered imprudent to head out without both the 
large air conditioning units working. A refurbished compressor was shipped 
overnight from the east coast and the service company doing the installation 
and Brown's engineers worked through the Memorial Day holiday weekend to have 
the ship ready to leave on Monday, May 25 from Pearl Harbor (instead of May 
19 as originally planned). This delay took 6 days of the 38 days-at-sea 
allotted to Leg 2. Two days were returned to give a total of 34 days-at-sea, 
moving our arrival date in Seattle from June 25, as originally planned, to 
June 27. To account for the loss of 4 days, the secondary objective 
shelf/slope P17N repeat stations were removed from the cruise plan. The 
delayed return into Seattle also meant that one member of the science party 
could not participate, and a substitute data processor from SIO flew in from 
San Diego on short notice.

Generally speaking, the CTD, along with the many instruments on the package, 
behaved well. Effective water conservation practices meant that in spite of 
the large number of samples being taken, everyone was able to get the water 
they needed for analysis. In spite of a few sensor, plumbing, and battery 
issues with individual instruments on the rosette (see individual instrument 
sections), no major technical difficulties occurred. Those on the deck and in 
the winch house mastered the coordinated use of wires from both the aft 
(rosette package) and forward (bongo net) winch blocks. There was one 
incident when the package connected with the side of the ship as it swung out 
of the water, but no issues with the instrumentation occurred afterward. The 
greatest technical challenge came when the need arose to switch the rosette 
from the aft winch block to the forward winch block.

Throughout the voyage the ship was quite concerned about the lifetime of the 
aft winch wire, which at only 2 months old was already showing signs of rust, 
first below 4000 m and then below 5000 m. Although the wire was lubed on leg 
1, this lubing was done on one cast and the wire was immediately deployed 
(and hence rinsed) on the next cast. The manufacturer suggested a particular 
applicator (purchased while in port in Hawaii) and a two-day soak period 
before using the wire again for the next lubrication. It made sense to do the 
lubing on a deeper cast. Short term science goals made lubing the wire 
undesirable due to loss of time switching blocks, reterminating the forward 
wire, and the possible effects on organics measurements. On the other hand, 
knowing the need for GO-SHIP cruises to be possible on the Brown well into 
the future, it was recognized that wire maintenance was necessary. In an 
effort to impact the science as little as possible, the forward wire was 
prepared ahead of time and the decision was made to give up bongos for two 
nights. The lubing was performed on station 141 (5844 m depth). The last 500 
m of wire were not lubed.

On the next station (142), deployment of the package on the forward winch saw 
multiple modulo and modem errors on the 1000 m cesium cast. Although, it 
appeared all bottles had fired properly on the short cast, the sheer number 
of errors that occurred early in the subsequent full cast required that the 
cast be aborted. Keeping focus on the primary objective of completing the 
occupation the 152°W line, rather than moving on, it was decided to stay on 
station and reterminate. Modem errors continued on ensuing casts until the 
junction box connections and slip rings were changed. However, throughout 
this period, the data from the package appeared reasonable and all bottles 
fired as expected. Upon return to the aft winch similar problems were 
encountered, and were dealt with in a similar manner (although no 
reterminations were necessary). In the end, only about 3 hours were lost due 
to the extra retermination, along with some further time associated with 
slower deployments and recoveries on the unfamiliar forward winch (which 
required an air tugger to place the rosette on its platform upon recovery) 
and another 45 minutes due to an unrelated mishap with LADCP that required 
that the battery be changed out. The DO 14C group moved one of their sampling 
positions slightly further north to avoid contamination, and DOC was measured 
on the two stations after the lubing to see whether any effect would be 
visible. Further details on particular sensor issues encountered during the 
cruise are provided later in this document.

With only a few days of mild rain and choppy waters, throughout most of the 
cruise, the weather was very comfortable for sampling operations. Two days 
were more than excellent with bright sunshine and complete calm. On the trips 
northward and eastward through the Gulf of Alaska the lengthening of the day 
to midsummer was made less apparent by the thick fog that enshrouded the 
ship, reduced visibility and caused incessant sounding of the ship's horn. 
The fog did not, however, impede the progress of sampling. Although the calm 
waters were an asset the fog did not make for ideal conditions for the 
spectro-radiometer casts, which continued nevertheless.

One item we do wish to report concerns the multi-beam bathymetric recorder. 
Perhaps those with greater familiarity with these instruments would have 
known better, but we report the following experience as a cautionary tale for 
GOSHIP cruises which regularly run the multi-beam underway while steaming at 
full speed. While running at more than 11.5 knots in 4000 m of water, the CTD 
watch glanced up to see a huge circular crater more than 6000 m deep on the 
multi-beam display. The ship steamed straight across the center of this 
feature. A couple of days later, a similar feature was seen with the ship's 
track skirting the edge of a seemingly circular 6000+ m drop off. The 
bathymetric map said it was a seamount. After the station 4 nm away, time was 
taken to go back for a second look with all bathymetric readers running at 
the recommended survey speed of 8 knots. No crater was found, only the 
seamount. The suspicion is that this is a multi-beam glitch that occurs when 
the gates are set for a specific depth range and suddenly a much shallower 
feature appears. On the display black dropouts surrounding the deeper values 
indicate the problem.

All over-the-side operations were completed on the morning of 23 June. Once 
out of Canadian EEZ waters on our steam to Seattle, underway measurements and 
in particular, underway surface cesium sampling resumed. On P16N/Leg 2, all 
the planned stations (barring the shelf loop removed during our delay in 
Hawaii) and 2 extra, for a total of 95 stations (not including the test 
station) were completed. At these locations the rosette was lowered with CTD 
& oxygen sensors, transmissometer, LADCP, UVP, and chi-pods in and out of the 
water 115 times. We performed bongo operations every night, except for the 2 
nights when the lubrication was soaking into the wire (29 in total), C-Ops 
occurred every day there was any chance of getting results (32 times), and 5 
Argo floats were deployed.


Table P16N: Argo Float Deployment

       Float S/N  Date/Time Deployed  Lat  Lon   CenterBeam Depth
       ---------  ------------------  ---  ----  ----------------
       ARGO 462    2015-06-02 23:41    32N  152W       5436
       ARGO 463    2015-06-04 06:15    35N  152W       5714
       ARGO 464    2015-06-11 06:01    46N  152W       5341
       ARGO 466    2015-06-13 04:28    49N  152W       5023
       ARGO 467    2015-06-14 22:23    52N  152W       5107


Along the way, analysis of the observations began, in particular the 
examination of thermocline and deep changes since the previous P16N 
occupation in 2006. Quality control through the checking for systematic 
offsets between the two occupations was also continuously performed. One 
feature that has drawn much public attention, the elevated sea surface 
temperatures in the northeastern North Pacific (aka "the blob") that have 
been affecting Pacific Northwest climate, is clearly visible in 2015 underway 
SST data. We look forward to all the efforts that will analyze and synthesize 
our new P16N data in a larger context.


Acknowledgements

The successful completion of the cruise relied on dedicated assistance from 
many individuals on shore and on the NOAA ship Ronald H. Brown. Funded 
investigators in the project and members of the GO-SHIP Repeat Hydrography 
program were instrumental in planning and executing the cruise. We would like 
to thank everyone who has participated in 2015 GO-SHIP P16N repeat, onboard 
and on land, and who has helped make this cruise a success. The collaboration 
between leg 1 and leg 2 participants began in the planning stages and was 
strong on all fronts. All Leg 2 cruise participants displayed dedication and 
camaraderie throughout their 34 days at sea as well as during the initial 
week delay.

Officers and crew of the Ronald H. Brown exhibited a high degree of 
professionalism and assistance to accomplish the mission and to make us feel 
at home during the voyage. The crew was an enormous help with all aspects of 
our operations, especially in orchestrating the dance among the CTD, Bongo 
and C-ops. The Brown's engineers worked tirelessly to keep the ship running. 
The mess crew kept us well fed and provided thrice-daily doses of humor. Our 
winch operators took us to the bottom of the ocean and back again 115 times. 
The Brown's operations officer Lt. Adrienne Hopper started early providing 
the co-chiefs of both legs with an onshore connection to the ship, answering 
questions and assisting in the definition of the cruise instructions. Onboard 
Lt. Hopper provided an open, responsive and always positive connection 
between the science party and crew. The CO Robert Kamphaus led operation 
safety meetings during the cruise with the co-chiefs six days a week that 
were not only informative, but also further strengthened the crew/science 
party relationship. Other individuals we wish to thank include: Electronics 
Technician Jeff Hill and Bosun Bruce Cowden, who together with the science 
party's CTD-processor/ET Jay Hooper and salt analyst/ET Andy Stefanick 
provided a wealth of troubleshooting experience to get us out of all 
logistical, technical and mechanical difficulties. Although many on the Brown 
bring a long history of experience to their jobs, Leg 2 began with new crew 
members on the bridge, in the winch house, and on the deck working alongside 
numerous first timers in the science party. It is only through the combined 
efforts of all parties that safe and efficient progress was made. It was the 
team spirit among scientists, officers, and crew that made the cruise 
particularly enjoyable. We would like to acknowledge and thank all of them.

On land, CDR Thomas Pelzer provided much needed help with both the writing of 
the cruise instructions and the connection to the Brown. The US Repeat 
Hydrography / CO2 Program is sponsored by NOAA's Office of Climate 
Observation. In particular, we wish to thank program managers Kathy Tedesco 
(NOAA), Eric Itsweire (NSF/OCE) and Donald Rice (NSF/OCE) for their financial 
and moral support of the effort.



P16N Leg 2 Participating Institutions


Abbreviation  Institution
------------  ---------------------------------------------------------------
AOML          Atlantic Oceanographic and Meteorological Laboratory - NOAA
APL           Applied Physics Laboratory - UW
CIMAS         Cooperative Institute for Marine and Atmospheric Studies - 
RSMAS/UM
JISAO         Joint Institute for the Study of the Atmosphere and Ocean - UW
LDEO          Lamont-Doherty Earth Observatory - Columbia University
MIT           Massachusetts Institute of Technology
MPL           Marine Physical Laboratory - SIO
ODF           Oceanographic Data Facility (Shipboard Technical Support) - SIO
PMEL          Pacific Marine Environmental Laboratory - NOAA
RSMAS         Rosenstiel School of Marine and Atmospheric Science - UM
SIO           Scripps Institution of Oceanography
UAF           University of Alaska Fairbanks
UCI           University of California, Irvine
UCSB          University of California, Santa Barbara
UCSD          University of California, San Diego
UM            University of Miami
UW            University of Washington
WHOI          Woods Hole Oceanographic Institution




Principal Programs of P16N Leg 2

                                     Principal 
Analysis                Institution  Investigator       email
----------------------  -----------  -----------------  -------------------------
CTDO                    NOAA/PMEL    Gregory Johnson    Gregory.CJohnson@noaa.gov
                        NOAA/AOML    Molly Baringer     Molly.Baringer@noaa.gov

Fluorometer/C-OPS       UCSB/ERI     Norm Nelson        norm@eri.ucsb.edu

Transmissometer         TAMU         Wilford Gardner    wgardner@ocean.tamu.edu

Underwater Vision       UAF          Andrew McDonnell   amcdonnell@alaska.edu
Profiler (UVP)   

Lowered ADCP            LDEO         Andreas Thurnherr  ant@ldeo.columbia.edu

Chipods                 OSU          Jonathan Nash      nash@coas.oregonstate.edu
                        SIO/ODF      James Swift        jswift@ucsd.edu

Data Management         SIO/ODF      Susan Becker       sbecker@ucsd.edu

Chlorofluorocarbons     NOAA/PMEL    John Bullister     John.L.Bullister@noaa.gov
(CFCs)/SF6/N2O  

3He/Neon/Tritium        WHOI         William Jenkins    wjenkins@whoi.edu

Dissolved O2            RSMAS        Chris Langdon      clangdon@rsmas.miami.edu
                        NOAA/AOML    Molly Baringer     Molly.Baringer@noaa.gov

Total CO2 (DIC)         NOAA/PMEL    Simone Alin        Simone.R.Alin@noaa.gov
/UW pCO2                NOAA/AOML    Rik Wanninkhof     Rik.Wanninkhof@noaa.gov

Total Alkalinity/pH     SIO/MPL      Andrew Dickson     adickson@ucsd.edu

l3C/14C-DIC             PU           Robert Key         key@princeton.edu
                        WHOI         Ann McNichol       amcnichol@whoi.edu

DOC/TDN                 RSMAS        Dennis Hansell     dhansell@miami.edu

DO14C/Black Carbon      UCI/ESS      Ellen Druffel      edruffel@uci.edu

CDOM/POC/Chlorophyll a
UW HPLC Pigments/AP     UCSB/ERI     Norm Nelson        norm@eri.ucsb.edu
Spectroradiometry/AP

Nutrients               NOAA/PMEL    Calvin Mordy       Calvin.W.Mordy@noaa.gov

Salinity                NOAA/AOML    Molly Baringer     Molly.Baringer@noaa.gov
                        NOAA/PMEL    Gregory Johnson    Gregory.CJohnson@noaa.gov

137Cs/134Cs/90Sr/129I   WHOI         Ken Buesseler      kbuesseler@whoi.edu

Pteropods               NOAA/PMEL    Nina Bednarsek     Nina.Bednarsek@noaa.gov

ARGO Floats             NOAA/PMEL    Gregory Johnson    Gregory.CJohnson@noaa.gov

Shipboard ADCP          UH           Eric Firing        efiring@hawaii.edu
                        UH           Jules Hummon       hummon@hawan.edu



P16N Leg 2 Scientific Personnel

Duties                 Name                 Affiliation  email
---------------------  ----------------     -----------  --------------------------
Chief Scientist        Alison Macdonald     WHOI         macdonald@whoi.edu
Co-Chief Scientist     Sabine Mecking       APL/UW       mecking@uw.edu
Data Management        Courtney Schatzman   SIO/ODF      cschatzman@ucsd.edu
CTD Processing         James Hooper         AOML         James.Hooper@noaa.gov
CTD/Salinity/LADCP/ET  Andrew Stefanick     AOML         andrew.stefanick@noaa.gov
CTD/Salinity/LADCP/ET  Edward Hunt          CIIMAS       edhuntjones@gmail.com
CTD Watchstander       Andrew Shao          UW           ashao@uw.edu
CTD Watchstander       Amanda Fay           UWisc        arfay@wisc.edu
ADCP/LADCP             Darren McKee         LDEO         dmckee@ldeo.columbia.edu
Dissolved O2           Christopher Langdon  RSMAS        clangdon@rsmas.miami.edu
Dissolved O2           Maria Arroyo         UM           m.arroyo2@umiami.edu
Nutrients              Charles Fischer      AOML         Charles.Fischer@noaa.gov
Nutrients              Eric Wisegarver      PMEL         eric.wisegarver@noaa.gov
DIC/underway pCO2      Robert Castle        AOML         robert.castle@noaa.gov
DIC                    Brendan Carter       JISAO        brendan.carter@noaa.gov
CFCs/SF6               David Wisegarver     PMEL         David.Wisegarver@noaa.gov
CFCs/SF6               Sophia Wensman       UM           sophiamw@umich.edu
TALK                   David Cervantes      UCSD         dlcervantes@ucsd.edu
TALK                   August Pereira       UCSD         august.l.pereira@gmail.com
pH                     Michael Fong         UCSD         mbfong@ucsd.edu
Helium/Tritium         Zoe Sandwith         WHOI         zsandwith@whoi.edu
CDOM                   Erik Stassinos       UCSB         eriks@eri.ucsb.edu
CDOM                   Kelsey Bisson        UCSB         kbiss0990@gmail.com
Chipod                 Bryan Kaiser         WHOI/MIT     bryankais@gmail.com
UVP/Bongo              Jessica Turner       UAF          jessie.turner@alaska.edu
DO 14C/black carbon    Brett Walker         UCI          Brett.walker@uci.edu
DOC/TDN                Benjamin Granzow     UM           b.granzow@umiami.edu
Cesium Isotopes        Steven Pike          WHOI         spike@whoi.edu




P16N Leg 2 Ship's Crew
 
Crew Member           Position                 Crew Member            Position
--------------------  -----------------------  ---------------------  --------------------
CAPT Robert Kamphaus  Commanding Officer       CB Bruce Cowden        Chief Bosun
LCDR Nicole Manning   Executive Officer        BGL Reggie Williams    Bosun Group Leader
ENS David Owen        Navigation Officer       AB Vicky Carpenter     Able-Bodied Seaman
LT Adrienne Hopper    Operations Officer       AB William Sutton      Able-Bodied Seaman
ENS Dustin Picard     Safety Officer           AB Mike Lastinger      Able-Bodied Seaman
3M David Owen         Third Mate               AB James Deeton        Able-Bodied Seaman
LCDR James McEntee    Medical Officer
CME Frank Dunlop      Chief Engineer           CS Michael Smith       Chief Steward
1 AE Mike Ryan        1st Asst. Engineer       CC Orcino Tan          Chief Cook
2AE Ray Zarzycki      2nd Asst. Engineer       2C Emir PorterSecond   Cook
3AE Avery Edson       3rd Asst. Engineer       GVA George Washington  General Vessel Asst.
JUE Mike Robinson     Jr. Unlicensed Engineer
EU Mike Johnston      Engine Utilityman
                                               ST Scott Allen         Survey Tech.
CET Jeff Hill         Chief Electronics Tech.  ST Mark Bradley        Survey Tech.



Measurement Program Summary

A 24-position, 11-liter Bullister bottle rosette frame (NOAA/AOML) was used 
to collect data. The distribution of the bottle samples during the cruise can 
be seen in Figures 1 and 2 below.


Figure 1: P16N Leg 2 Sample distribution, stations 113-145.

Figure 2: P16N Leg 2 Sample distribution, stations 146-190.

Figure 3: P17E Leg 2 Sample distribution, stations 176 191-205.



Ship's Underway Data Acquisition

Navigation data were acquired at 1-second intervals from the ship's Furuno 
GP15O P-Code GPS receiver by the SIO/ODF Linux system from the start of the 
cruise. In addition, centerbeam depth data, with a correction for hull depth 
included in each data line, were acquired directly from the ship's 
SeabeamlKongsberg EM122 system. These data were used to connect the 
timestamps for each cruise deployment with position and ocean depth 
information.

The centerbeam depths were also continuously displayed, and data were 
manually recorded at cast start/bottom/end on CTD Cast Logs.

Etopo2 bathymetry data were merged with navigation time-series data after 
each cast and used for bottle-depth sections shown elsewhere in this report.

Various underway data were sent from the ship's computer systems to a serial 
feed on the Linux system. These data were stored at 1-second intervals:

Column  Data Type and units
------  ---------------------------------------------------------------
     1  Winch payout (uncorrected meters)
     2  Winch speed (meters/minute)
     3  Winch tension (pounds)
     4  Multibeam Bottom Depth (meters to tenths) - corrected for Sound   
        Velocity
        but not for hull depth (approx. 5.8m more)
     S  UTC Julian Date (day of year in 2015)
     6  UTC Time (hh:mm:ss) (hh=hours, mm=minutes, ss=seconds)
     7  GPS Latitude (ddmm.mmmniH) (d=degrees, m=minutes to 4 places, 
        H=Hemisphere)
     8  GPS Longitude (dddmm.mmmmH)
     9  TSG Sea Surface Temp (SST - degrees Celsius)
    10  TSG Sea Surface Salinity (last calibrated 7-Jan-2015)
    11  True Wind Speed (knots) - divide by 1.9438445 to get rn/sec
    12  True Wind Direction (compass degrees)
    13  Barometer - Sea Level (millibars)
    14  Relative Humidity (%)
    15  Air Temperature (degrees Celsius)



Underwater Electronics Package

A Sea-Bird Electronics SBE9plus CTD was connected to a 24-place SBE32 
carousel, providing for two-conductor sea cable operation. Two conducting 
wires in the 0.322 sea cable were soldered to their counterparts in the end 
termination: black for signal, and white for ground; the third (red) wire was 
cut back/unused. Power to the CTD and sensors, carousel and most instruments 
attached to the CTD was provided through the sea cable from an SBE1 l plus 
deck unit in the computer lab.

The CTD supplied a standard SBE-format data stream at a data rate of 24 Hz. 
The CTD provided pressure plus dual temperature, conductivity and dissolved 
oxygen channels. The CTD system also incorporated an altimeter, 
transmissometer, fluorometer, and Underwater Vision Profiler (UVP). A Lowered 
Acoustic Doppler Profiler (LADCP) and Chipods were also mounted on the 
rosette frame; both were powered separately and collected data internally.

The CTD system was outfitted with dual pumps. Primary temperature, 
conductivity and dissolved oxygen were plumbed into one pump circuit; and 
secondary temperature, conductivity and oxygen were plumbed into into the 
other. The CTD and sensors were deployed vertically. The primary temperature 
and conductivity sensors were used for reported CTD temperatures and 
salinities on all casts. The secondary temperature and conductivity sensors 
were used as calibration checks.


Table P16N: Underwater Package Configuration

Manufacturer/Model           Serial No.    Calib.Date   Stations Used
===========================================================================
Markey DESH-5 Winch          AFT           n/a          999,113-141,146-207
                             FWD           n/a          142-145

Electrical and Mechanical                               142/2
  Reterminations Before    
  These Stations
———————————————————————————————————————————————————————————————————————————
Sea-Bird SBE11plus           11P9852-0367               999,113-185,187-207
  Deck Unit                  11P111660                  186
———————————————————————————————————————————————————————————————————————————
Sea-Bird 5BE32 Carousel      1032          n/a          999,113-207
  Water Sampler (24-place)
———————————————————————————————————————————————————————————————————————————
Sea-Bird SBE35RT Reference   0072          03-Jan-2012  999,113-207
  Temperature  
===========================================================================
Sea-Bird SBE9plus CTD        0489          05-Sep-2014  999,113-207
  Paroscientific Digiquartz  0489-67264
  Pressure    
———————————————————————————————————————————————————————————————————————————
Primary Sea-Bird Sensors:
  SBE3plus Temperature (T1)  03P-4341      20-Jan-2015  999,113-207

  SBE4C Conductivity (C1)    04-3157       21-Jan-2015  999,113-207

                             43-1835       03-Feb-2015  999, 113-163
  SBE43 Dissolved Oxygen     43-2934       02-Aug-2014  163-165
                             43-0315       06-Feb-2015  166-207

  SBE5 Pump                  05-5855       n/a          999,113-162
                             05-5946                    163-205
———————————————————————————————————————————————————————————————————————————
Secondary Sea-Bird Sensors:
  SBE3plus Temperature (T2)  03P-4193      20-Jan-2015  999,113-207

  SBE4C Conductivity         04-3068       22-Jan-2015  999,113-207
    Sensor (C2)

                             43-0312       05-Mar-2015  999,113-149,151-207
  SBE43 Dissolved Oxygen     43-1890       15-Jan-2015  150/2
                             43-0313       03-Feb-2015  150/3

                             05-3481       n/a          999,113-162/1
  SBE5Pump                   05-5946       n/a          162/2
                             05-5855       n/a          163-207
=============================================================================
Other Devices Connected to CTD:

Valeport VASOO Altimeter     47972         n/a          999, 113-176
                             47973         n/a          177-207
=============================================================================
HYDROPTIC UVP5 Underwater    009           12-Sep-2013  999, 113-207
  Vision Profiler                                       (internally recorded)

WETLabs C-Star               CST-1636DR    08-Oct-2013  113-207
  Transmissometer   
=============================================================================
Teledyne RDI WHM150-1-UG15 LADCP

  150KHz Downlooker/Master   19394                      999,113-117,134-207

  300KHz Downlooker/Master   12243                      118-133

  300KHz Uplooker/Slave      13330                      113-171

  300KHz Uplooker/Slave      12243                      172-207
=============================================================================
Chipod Serial Nos. (OSU-assembled - no Mfr)

  Up/Down  Logger  Pressure                Sensor
  Looker   Board   Case      Sensor        Holder       Stations Used
———————————————————————————————————————————————————————————————————————————
  Up       2015    Ti44-6    14-26D        1            113-207
  Up       2016    Ti44-1    14-28D        4            113-146
  Up       2014    Ti44-8    14-28D        4            147-207
  Down     2010    Ti44-5    11-23D        2            113-207
  Down     2019    Ti44-3    14-27D        6            113-142
  Down     2013    Ti44-3    14-27d        6            143-180,182-207




Underwater Electronics Package Challenges

The NOAAS Ronald H. Brown has two Markey DESH-5 winches. The AFT winch was 
used for most casts on P16N. The FWD winch was used for stations 142-148. 
Reterminations of the winch wires are listed in the first part of the table 
preceeding this section.

The CTD was switched over to the forward winch after lubricating the aft 
winch cable during station 141. Several modulo and unsupported modem errors 
where seen in stations 142 and 143. The slip ring was replaced by Jeff Hill 
on the forward winch, which resolved the issues.

Station 150 had large oxygen differences during the surface soak. The 
secondary oxygen sensor, 312, was replaced with s/n 1890 for the cast two and 
then s/n 0313 for cast two, both of which still had large differences. 
Returned to s/n 312 where differences returned to acceptable values.

Station 162 had large differences in the sensors. Replaced secondary pump s/n 
0819 with s/n 3481, which was also bad, and then s/n 5446 which resolved the 
differences issue.

Station 163 primary oxygen sensor s/n 1835 was replaced with s/n 2943 after 
differences of approximately 80 umol/kg during the surface soak. Reversed the 
pump configuration to address oxygen sensor spiking issues. Did not resolve 
the issue, but the configuration was kept the rest of the cruise.

Station 166 replaced primary oxygen s/n 2943 with s/n 0315 after continued 
oxygen spikes and large oxygen differences. Primary oxygen cable was replaced 
and resolved the large oxygen spikes at depth.

Station 186 deck unit s/n 1 1P9852 - 0367 would no longer initialize the NMEA 
feed and was swapped with s/n 1P1 11660. Large spikes were seen in the 
voltage channels.

Station 187 determined that the replacement deck unit s/n 1P1 11660 was 
causing the voltage spikes across all voltage channel and replaced with s/n 1 
1P9852 - 0367 and the NMEA feed went through the computer on COM 4.


Water Sampling Package

All rosette casts were lowered to within 8-12 meters of the bottom, using the 
multibeam center depth value plus the altimeter on the rosette to determine 
distance. Three sampling schema were used in rotation to stagger standard 
sampling depths for consecutive stations. There were occasional exceptions 
made to the order of the schema or to capture a feature in the water column.

Rosette maintenance was performed on a regular basis. O-rings were changed 
and lanyards repaired as necessary. Bottle maintenance was performed each day 
to ensure proper closure and sealing. Valves were inspected for leaks and 
repaired or replaced as needed. Periodic leaks were noted on sample logs. 
These are documented in the quality comments section of the Appendix.


Bottle Sampling

At the end of each rosette deployment water samples were drawn from the 
bottles in the following order:

  •  Chlorofluorocarbons(CFCs)/N2O/SF6
  •  3 Helium/Neon
  •  Dissolved O2
  •  Dissolved Inorganic Carbon (DIC)
  •  Total pH
  •  Total Alkalinity (TAlk)
  •  13C/14C-DIC
  •  Dissolved Organic Carbon/Total Dissolved Nitrogen (DOC/TDN)
  •  DO 14C
  •  Colored Dissolved Organic Matter (CDOM)
  •  POC
  •  Chlorophyll a
  •  Tritium
  •  Neon
  •  Nutrients
  •  Salinity
  •  137Cs/134Cs/90Sr/129I
  •  Black Carbon

The correspondence between individual sample containers and the rosette 
bottle position was recorded on the sample log for the cast. This log also 
included any comments or anomalous conditions noted about the rosette and 
bottles. One member of the sampling team was designated the sample cop, whose 
sole responsibility was to maintain this log and insure that sampling 
progressed in the proper drawing order.

Normal sampling practice included opening the drain valve and then the air 
vent on the bottle, indicating an air leak if water leaked. This observation 
together with other diagnostic comments (e.g., "lanyard caught in endcap", 
"valve left open") that might later prove useful in determining sample 
integrity were routinely noted on the sample log. Drawing oxygen samples also 
involved taking the draw temperature from the bottle. The temperature was 
noted on the sample log and was sometimes useful in determining leaking or 
mis-tripped bottles.

Once individual samples had been drawn and properly prepared, they were 
distributed for analysis. On-board analyses were performed on computer-
assisted analytical equipment networked to the data processing computer for 
centralized data management.


Bottle Data Processing

Water samples collected and properties analyzed shipboard were managed 
centrally in a relational database (PostgreSQL-8.1.23-1O) run on a CentOS-
5.11 Linux system. A web service (OpenACS-5.3.2-3 and AOLServer-4.5.1-1) 
front-end provided ship-wide access to CTD and water sample data. Web-based 
facilities included on-demand arbitrary property-property plots and vertical 
sections as well as data uploads and downloads.

Shipboard CTDO data were re-processed automatically at the end of each 
deployment using SIO/ODF CTD processing software v.5.1.6-i. The CTDO data and 
bottle trip files acquired by SBE SeaSave on the Windows 7 workstation were 
copied onto the Linux database and web server system. Pre-cruise calibration 
data were applied to CTD Pressure, Temperature and Conductivity sensor data, 
then the data were processed to a 0.5-second time series. A 1-decibar down-
cast pressure series was created from the time series.

CTD up-cast data at bottle trips were extracted and added to the bottle 
database to use for CTD Pressure, Temperature and Salinity data in the 
preliminary bottle files. Pre-cruise calibration data were applied to these 
three parameters, in addition to PMEL preliminary shipboard conductivity 
corrections.

Time-series CTDO data from both down- and up-casts were matched along 
isopycnals to upcast trip data, then fit to bottle O2 data using the SIO/ODF 
CTD processing software. The coefficients from these fits were applied, then 
CTD Oxygen data were extracted from the time-series up-cast data files and 
added to the database for quality control of bottle Dissolved O2 data.

The NOAA/PMEL final PTSO data will replace the preliminary SIO/ODF CTD data 
in the bottle files after submission to CCHDO.

Cast Log and Sample Log information plus any diagnostic comments were entered 
into the database once sampling was completed. Quality flags associated with 
sampled properties were set to indicate that the property had been sampled, 
and sample container identifications were noted where applicable (e.g., 
oxygen flask number).

Analytical results were provided on a regular basis by the various analytical 
groups and incorporated into the database. These results included a quality 
code associated with each measured value and followed the coding scheme 
developed for the World Ocean Circulation Experiment (WOCE) Hydrographic 
Programme (WHP) [Joyc94].

Various consistency checks and detailed examination of the data continued 
throughout the cruise. Log notes were cross referenced with sample data 
values and quality coded. A summary of Cast Log and Sample Log comments, mis-
trips, bottle lanyard issues and associated quality codes can be found in the 
Appendix.


Collected Samples


Table P16N: Samples Collected and/or Analyzed On-Board

     Samples Analyzed On-Board          Samples Collected (Not Analyzed)
     ---------------------------------  --------------------------------
     Chlorofluorocarbons(CFCs)/SF6/N2O  3He/Neon/Tritium
     Dissolved O2                       13C/14C-DIC
     Total CO2 (DIC)                    DOC/TDN
     Total Alkalinity/pH/pH Dye         DO 14C/Black Carbon
     Chlorophyll a                      CDOM/POC
     Nutrients                          137Cs/134Cs/90Sr/129I
     Salinity


Ship-Board Collection Analysis

The following figures are interpolated cross cections of samples collected 
and analyzed or calculated through out P16N Leg 2.


Figure P16N Leg 2 Potential Temperature Cross Section.

Figure P16N Leg 2 Potential Temperature Cross-Gyre Section.

Figure P16N Leg 2 Salinity Cross Section.

Figure P16N Leg 2 Salinity Cross-Gyre Section.

Figure P16N Leg 2 Potential Density Cross Section.

Figure P16N Leg 2 Potential Density Cross-Gyre Section.

Figure P16N Leg 2 CFC12 Cross Section.

Figure P16N Leg 2 CFC12 Cross-Gyre Section.

Figure P16N Leg 2 CFC11 Cross Section.

Figure P16N Leg 2 CFC1 1 Cross-Gyre Section.

Figure P16N Leg 2 SF6 Cross Section.

Figure P16N Leg 2 SF6 Cross-Gyre Section.

Figure P16N Leg 2 Oxygen Cross Section.

Figure P16N Leg 2 Oxygen Cross-Gyre Section.

Figure P16N Leg 2 DIC Cross Section.

Figure P16N Leg 2 DIC Cross-Gyre Section.

Figure P16N Leg 2 pH Cross Section.

Figure P16N Leg 2 pH Cross-Gyre Section.

Figure P16N Leg 2 Total Alkalinity Cross Section.

Figure P16N Leg 2 Total Alkalinity Cross-Gyre Section.

Figure P16N Leg 2 Silicate Cross Section.

Figure P16N Leg 2 Silicate Cross-Gyre Section.

Figure P16N Leg 2 Nitrate Cross Section.

Figure P16N Leg 2 Nitrate Cross-Gyre Section.

Figure P16N Leg 2 Nitrite Cross Section.

Figure P16N Leg 2 Nitrite Cross-Gyre Section.

Figure P16N Leg 2 Phosphate Cross Section.

Figure P16N Leg 2 Phosphate Cross-Gyre Section.




    CHLOROFLUOROCARBON (CFC) AND SULFUR HEXAFLUORIDE (SF6) MEASUREMENTS ON
                             GO-SHIP P16N Leg 2

PI:       John Bullister

Analysts: David Wisegarver
          Sophia Wensman

Chlorofluorocarbon (CFC) and Sulfur Hexafluoride (SF6)

A PMEL analytical system (Bullister and Wisegarver, 2008) was used for CFC-
11, CFC-12, sulfur hexafluoride (SF6) and nitrous oxide analyses on the 
CLIVAR pi 6N expedition. Greater than 1800 samples of dissolved CFC-ll, CFC-
l2 and SF6 ('CFC/SF6') were analyzed.

In general, the analytical system performed well for CFC- 12, SF6 and nitrous 
oxide during the cruise. There were some analytical problems with CFC- ii. 
Typical dissolved SF6 concentrations in modern surface water are ~1-2 fmol 
kg-1 seawater (1 fmo l= femtomole = 10(^-15) moles), approximately 1000 times 
lower than dissolved CFC-11 and CFC-12 concentrations. The limits of 
detection for SF6 were approximately 0.03 fmol kg-1 on this cruise. SF6 
measurements in seawater remain extremely challenging. Improvements in the 
analytical sensitivity to this compound at low concentrations are essential 
to make these measurements more routine on future CLIVAR cruises.

Water samples were collected in bottles designed with a modified end-cap to 
minimize the contact of the water sample with the end-cap O-rings after 
closing. Stainless steel springs covered with a nylon powder coat were 
substituted for the internal elastic tubing provided with standard Niskin 
bottles. When taken, water samples collected for dissolved CFC-11, CFC-12 and 
SF6 analysis were the first samples drawn from the bottles. Care was taken to 
coordinate the sampling of CFC/SF6 with other samples to minimize the time 
between the initial opening of each bottle and the completion of sample 
drawing. Samples easily impacted by gas exchange (dissolved oxygen, 3He, DIC 
and pH) were collected within several minutes of the initial opening of each 
bottle. To minimize contact with air, the CFC/SF6 samples were drawn directly 
through the stopcocks of the bottles into 250 ml precision glass syringes 
equipped with three-way plastic stopcocks. The syringes were immersed in a 
holding tank of clean surface seawater held at ~10°C until 20 minutes before 
being analyzed. At that time, the syringe was place in a bath of surface 
seawater heated to 32°C.

For atmospheric sampling, a 75 m length of 3/8" OD Dekaron tubing was run 
from the CFC van, located on the fantail, to the bow of the ship. A flow of 
air was drawn through this line into the main laboratory using an Air Cadet 
pump. The air was compressed in the pump, with the downstream pressure held 
at ~1.5 atm, using a backpressure regulator. A tee allowed a flow of ~100 ml 
min-1 of the compressed air to be directed to the gas sample valves of the 
CFC/SF6 analytical systems, while the bulk flow of the air (>7 1 min-1) was 
vented through the back-pressure regulator. Air samples were analyzed only 
when the relative wind direction was within 60 degrees of the bow of the ship 
to reduce the possibility of shipboard contamination. Analysis of bow air was 
performed at ~10 locations along the cruise track. At each location, at least 
five air measurements were made to increase the precision of the 
measurements.

Concentrations of CFC-11, CFC-12 and SF6 in air samples, seawater, and gas 
standards were measured by shipboard electron capture gas chromatography (EC-
GC) using techniques modified from those described by Bullister and Weiss 
(1988) and Bullister and Wisegarver (2008), as outlined below. For seawater 
analyses, water was transferred from a glass syringe to a glass-sparging 
chamber (volume 200 ml). The dissolved gases in the seawater sample were 
extracted by passing a supply of CFC/SF6 free purge gas through the sparging 
chamber for a period of 6 minutes at 200 ml min'. Water vapor was removed 
from the purge gas during passage through a Nafion drier. Carbon dioxide was 
removed with an 18 cm long, 3/8" diameter glass tube packed with Ascarite and 
a small amount of magnesium perchlorate desiccant. The sample gases were 
concentrated on a cold-trap consisting of a 1/16" OD stainless steel tube 
with a 2.5 cm section packed tightly with Porapak Q, a 15 cm section packed 
with Carboxen 1000 and a 2.5 cm section packed with MS5A. A Neslab Cryocool 
CC-100 was used to cool the trap to -70°C. After 6 minutes of purging, the 
trap was isolated, and it was heated electrically to 170°C. The sample gases 
held in the trap were then injected onto a precolumn (~61 cm of 1/8" O.D. 
stainless steel tubing packed with 80-100 mesh Porasil B, held at 80°C) for 
the initial separation of CFC-12, CFC-11, SF6 from later eluting peaks.

After the SF6 and CFC-12 had passed from the pre-column and into the second 
pre-column (26 cm of 1/8" O.D. stainless steel tubing packed with MS5A, 
160°C) and into the analytical column #1(174 cm of 1/8" OD stainless steel 
tubing packed with MS5A + 60 cm Porasil C held at 80°C), the outflow from the 
first pre-column was diverted to the second analytical column (180 cm 1/8" OD 
stainless steel tubing packed with Porasil B, 80-100 mesh, held at 80°C). The 
gases remaining after CFC- 11 had passed through the first pre-column, were 
backflushed from the precolumn and vented. After CFC- 12 had passed through 
the second pre-column, a flow of ArgonMethane (95:5) was used to divert the 
N2O to a third analytical column (30 cm of MS5A, 150°C). Column #3 and the 
second pre-column were held in a Shimadzu GC8 gas chromatograph with an 
electron capture detector (ECD) held at 330°C. Columns #1, and the first pre-
column were in another Shimadzu GC8 gas chromatograph with ECD. The column #2 
was also in a Shimadzu GC8 gas chromatograph with the ECD held at 330°C.

The analytical system was calibrated frequently using a standard gas of known 
CFC/SF6 composition (PMEL-WRS-72611). Gas sample loops of known volume were 
thoroughly flushed with standard gas and injected into the system. The 
temperature and pressure was recorded so that the amount of gas injected 
could be calculated. The procedures used to transfer the standard gas to the 
trap, pre-columns, main chromatographic column, and ECD were similar to those 
used for analyzing water samples. Four sizes of gas sample loops were used. 
Multiple injections of these loop volumes could be made to allow the system 
to be calibrated over a relatively wide range of concentrations. Air samples 
and system blanks (injections of loops of CFC/SF6 free gas) were injected and 
analyzed in a similar manner. The typical analysis time for seawater, air, 
standard or blank samples was ~11 minutes. Concentrations of the CFC-11 and 
CFC-12 in air, seawater samples, and gas standards are reported relative to 
the SIO98 calibration scale (Cunnold et al., 2000; Bullister and Tanhua, 
2010). Concentrations of SF6 in air, seawater samples, and gas standards are 
reported relative to the SIO-2005 calibration scale (Bullister and Tanhua, 
2010). Concentrations in air and standard gas are reported in units of mole 
fraction CFC in dry gas, and are typically in the parts per trillion (ppt) 
range. Dissolved CFC concentrations are given in units of picomoles per 
kilogram seawater (pmol kg-1) and SF6 concentrations in fmol kg-1. CFC/SF6 
concentrations in air and seawater samples were determined by fitting their 
chromatographic peak areas to multi-point calibration curves, generated by 
injecting multiple sample loops of gas from a working standard (PMEL cylinder 
WRS72611) into the analytical instrument. The response of the detector to the 
range of moles of CFC/SF6 passing through the detector remained relatively 
constant during the cruise. Full-range calibration curves were run at several 
times during the cruise and partial curves were run as frequently as 
possible, usually while sampling. Single injections of a fixed volume of 
standard gas at one atmosphere were run much more frequently (at intervals of 
90 minutes) to monitor short-term changes in detector sensitivity.

The purging efficiency was estimated by re-purging a high-concentration water 
sample and measuring the residual signal. At a flow rate of 200 cc min-1 for 
6 minutes, the purging efficiency for SF6 and both CFC gases was > 99%. The 
efficiency for N2O was about 97%.

On this expedition, based on the analysis of more than 150 pairs of duplicate 
samples, we estimate precisions (1 standard deviation) of about 1% or 0.003 
pmol kg-1 (whichever is greater) for dissolved CFC-l2 and 1% or 0.005 pmol 
kg-1 for CFC-ll measurements. The estimated precision for SF6 was 2% or 0.03 
fniol kg-1, (whichever is greater). Overall accuracy of the measurements (a 
function of the absolute accuracy of the calibration gases, volumetric 
calibrations of the sample gas loops and purge chamber, errors in fits to the 
calibration curves and other factors) is estimated to be about 2% or 0.004 
pmol kg' for CFC11 and CFC-12 and 4% or 0.04 fmol kg-1 for SF6).

A small number of water samples had anomalously high CFC-12 and/or SF6 
concentrations relative to adjacent samples. These samples occurred 
sporadically during the cruise and were not clearly associated with other 
features in the water column (e.g., anomalous dissolved oxygen, salinity, or 
temperature features). This suggests that these samples were probably 
contaminated with CFCs/SF6 during the sampling or analysis processes.

Measured concentrations for these anomalous samples are included in the data 
file, but are given a quality flag value of either 3 (questionable 
measurement) or 4 (bad measurement). Less than 2% of samples were flagged as 
bad or questionable during this voyage. A quality flag of 5 was assigned to 
samples which were drawn from the rosette but never analyzed due to a variety 
of reasons (e.g., leaking stopcock, plunger jammed in syringe barrel, etc).

A small number of peaks on the SF6/CFC-12 channel were lost due to RF 
interference and were flagged as bad (4).

Some nitrous oxide samples had very high restrips in low oxygen zones and 
were not used in the determination of the stripper efficiency corrections. In 
addition, the nitrous oxide stripper blanks increased with time and to reduce 
the blank, the stripper frit was periodically washed with 10% HCl.





References 

Bullister, J.L., and T. Tanhua (2010): Sampling and measurement of 
    chlorofluorocarbons and sulfur hexafluoride in seawater. In The GO-SHIP 
    Repeat Hydrography Manual: A Collection of Expert Reports and Guidelines. 
    E.M. Hood, C.L. Sabine, and B.M. Sloyan (eds.), IOCCP Report Number 14, 
    ICPO Publication Series Number 134. Available online at http://www.go-
    ship. org/HydroMan.html

Bullister, J.L., and R.F. Weiss, 1988: Determination of CC13F and CC12F2 in 
    seawater and air. Deep-Sea Res., y. 25, pp. 839-853.

Bullister, J.L., and D.P. Wisegarver (2008): The shipboard analysis of trace 
    levels of sulfur hexafluoride, chlorofluorocarbon-1 1 and 
    chlorofluorocarbon-12 in seawater. Deep-Sea Res. I, 55,1063-1074.

Prinn, R.G., R.F. Weiss, P.J. Fraser, P.G. Simmonds, D.M. Cunnold, F.N. 
    Alyea, S. O'Doherty, P. Salameh, B.R. Miller, J. Huang, R.H.J. Wang, D.E. 
    Hartley, C. Harth, L.P. Steele, G. Stunock, P.M. Midgley, and A. 
    McCulloch, 2000: A history of chemically and radiatively important gases 
    in air deduced from ALE/GAGE/AGAGE. J. Geophys. Res., y. 105, pp. 17,751-
    17,792.





HELIUM AND TRITIUM

PI: William Jenkins
Sampler: Zoe Sandwith


Helium Sampling

Helium and Tritium samples were collected roughly every three degrees on 
CLIVAR P16N Leg 2, for a total of 13 stations. A total of 194 helium samples 
were taken on Leg 2, which included 7 duplicates.

At each station sampled, 16 copper tube helium samples were drawn from the 
upper 2000m of the water column. Generally, at every other station sampled, a 
duplicate helium sample was drawn from a random depth in the upper 2000m. On 
the last station sampled, the profile was very shallow and only a surface 
sample was collected.

The copper tube used was 5/8" dehydrated refrigeration copper tube 
manufactured by Mueller Industries Inc. (Fulton, MS) and supplied in Soft 
rolls. These rolls were stored in the air-conditioned and low humidity bio-
analytical lab in order to limit corrosion and exposure risk. Poor quality 
copper can result in seal failure so great care is necessary in the handling 
of the copper in all stages of preparation, sampling, storage, and transport.

Approximately 1.5 hours before sampling a cast, the copper tubes were rolled 
out and cut into 30" sections. These sections were then flattened slightly so 
that after sampling and sealing of the copper tube samples, they could be re-
rounded in order to create a small headspace allowing for expansion of the 
seawater inside as it warmed.

In order to sample from the rosette with the copper tubes, they were attached 
to the Niskins using Tygon tubing with a small silicon tubing adaptor at the 
nipple end. Tubing would be attached to both ends of the copper tube, with 
the inlet tube coming in the bottom of the copper tube. Both pieces of Tygon 
tubing had plastic tubing clamps on them.

Water was drawn through the copper tube while gently knocking the tube with a 
thumper in order to remove any and all bubbles along the inside of the tubes. 
When satisfied that all bubbles had been cleared, and at least 2 volumes of 
water had flushed through, the sample was ready for sealing. The 2 plastic 
clamps were closed and the Tygon removed from the Niskin for transport to the 
hydraulic sealing jaws. The jaws run at 8000psi, press the copper together 
and cut it, creating a knife-edge seal and a gas tight sample chamber. 
Immediately after sealing, the tubes were re-rounded to create expansion 
space. After all samples were taken they were rinsed thoroughly with fresh 
water and dried before storing.

The only major issue encountered during Leg 2 was that for the first portion 
of the cruise the ship's air conditioner reheaters for the room were not 
functioning, resulting in a steady drop in room temperature as we steamed 
north. At its worst, the room temperature was down to 50°F, which was 
becoming unworkable. This was resolved midway through the cruise and the room 
temperature brought up to 60°F. It is unclear whether the reheaters were 
functioning or not on Leg 1, since the problem only became apparent as the 
cooling water temperature dropped in the northern latitudes. Other than that, 
the only problem was a failed hydraulic footpump, which was swapped out for a 
spare.


Tritium Sampling

A total of 194 tritium samples were taken, including 7 duplicates during Leg 
2 of PI6N. Tritium samples were drawn from the same stations and bottles as 
those sampled for helium. Duplicate tritium samples were drawn on the same 
stations that duplicate helium samples were taken. Due to water budgets, the 
duplicate tritium was taken on a different Niskin than the helium.

Tritium samples were taken using Tygon tubing to fill 1 liter glass jugs. 
Prior to the cruise, the jugs were baked in an oven, and backfilled with 
argon, then the caps were taped shut. While filling, the jugs were placed on 
the deck and filled to about 2 inches from the top of the bottle, taking care 
to not spill the argon gas out. Caps were replaced and taped shut with 
electrical tape before being packed for shipment back to WHOI. Tritium 
samples will be degassed in the lab at WHOI and stored for a minimum of 6 
months before mass spectrometer analysis.





DISSOLVED OXYGEN (discrete)

Maria Arroyo and Chris Langdon, Uni, of Miami (PIs: Chris Langdon, RSMAS, 
Molly Baringer, AOML)


Equipment and Techniques

Dissolved oxygen analyses were performed with an automated titrator using 
amperometric end-point detection [Langdon, 2012]. Sample titration, data 
logging, and graphical display were performed with a PC running a LabView 
program written by Ulises Rivero of AOML. Lab temperature was maintained at 
19.5-25.4°C. The temperature-corrected molarity of the thiosulfate titrant 
was determined as given by Dickson [1994]. Thiosulfate was dispensed by a 2 
ml Gilmont syringe driven with a stepper motor controlled by the titrator. 
The whole-bottle titration technique of carpenter [1965], with modifications 
by Culberson et al. [1991], was used. Three to four replicate 10 ml iodate 
standards were run every 3-4 days (SD<1 uL). The reagent blank was determined 
as the difference between V1 and V2, the volumes of thiosulfate required to 
titrate 1-ml aliquots of the iodate standard, was determined at the beginning 
and end of the cruise.


Sampling and Data Processing

Dissolved oxygen samples were drawn from Niskin bottles into calibrated 125-
150 ml iodine titration flasks using silicon tubing to avoid contamination of 
DOC and CDOM samples. Samples were drawn by counting while the flask was 
allowed to fill at full flow from the Niskin. This count was then doubled and 
repeated thereby allowing the flask to be overflowed by two flask volumes. At 
this point the silicone tubing was pinched to reduce the flow to a trickle. 
This was continued until a stable draw temperature was obtained on the Oakton 
meter. These temperatures were used to calculate umol/kg concentrations, and 
provide a diagnostic check of Niskin bottle integrity. 1 ml of MnCl2 and 1 ml 
of NaOH/Nal were added immediately after drawing the sample was concluded 
using a Re-pipetor. The flasks were then stoppered and shaken well. DIW was 
added to the neck of each flask to create a water seal. 24 samples plus two 
duplicates were drawn at each station. The total number of samples collected 
from the rosette was 2350.

The samples were stored in the lab in plastic totes at room temperature for 
30-40 minutes before analysis. The data were incorporated into the cruise 
database shortly after analysis.

Thiosulfate normality was calculated for each standardization and corrected 
to the laboratory temperature. This temperature ranged between 20.5 and 25.1 
C.

Reagent blanks were run at the beginning (1.4±0.3 uL), middle (1.6±0.8 uL) 
and end of the cruise (3.4±2.2 uL). Standards were May 25 708.2, May 29 
713.3, June 2 712.2, June 3 710.7, June 9 706.4, June 16 705.92 and June 22 
706.9.


Volumetric Calibration

The dispenser used for the standard solution (SOCOREX Calibrex 520) and the 
burette were calibrated gravimetrically just before the cruise. Oxygen flask 
volumes were determined gravimetrically with degassed deionized water at 
AOML. The correction for buoyancy was applied. Flask volumes were corrected 
to the draw temperature.


Duplicate Samples

Duplicate samples were drawn at two depths on every cast. The Niskins 
selected for the duplicates and hence the oxygen flasks were changed for each 
cast. A total of 170 sets of duplicates were run. The average standard 
deviation of all sets was 0.27 umol/kg.


Quality Coding

Preliminary quality code flags have been assigned to the oxygen data. Eighty-
three were coded bad based on Niskin mis-trips. Eighteen were flagged based 
on comparison with the preliminary calibrated CTD oxygen profiles.

O2 quality flag  Number  Note
---------------  ------  ----------------------------------------------------
3                15      Sample value high for profile and adjoining casts. 
                         Code questionable
4                16      Sample value low for profile. Top end cap not closed 
                         properly or leaking from the bottom. Assumed 
                         contaminated sample.
5                6       Sample value not reported a problem occurred during 
                         the titration (spilled, overshot endpoint).


Problems

The change in the code applied after leg J. to fix the problem with titrating 
samples with extremely low oxygen (<10 umol/kg) worked flawlessly on the leg 
2. Five oxygen flasks were either broken or deemed to have lose stoppers 
during the cruise and were replaced as follows: 

56 > 16 
59 > 23 
62 > 24 
68 > 18 
69 > 19

Cross-over comparisons 
None this cruise.



References

Carpenter, J. H., "The Chesapeake Bay Institute technique for the Winkler 
    dissolved oxygen method," Limnology and Oceanography, 10, pp. 141-143 
    (1965).

Culberson, C. H., Knapp, G., Stalcup, M., Williams, R. T., and Zemlyak, F., 
    "A comparison of methods for the determination of dissolved oxygen in 
    seawater," Report WHPO 91-2, WOCE Hydrographic Programme Office (Aug. 
    1991).

Dickson, A. G., "Determination of dissolved oxygen in seawater by Winkler 
    titration," WHP Operations and Methods (1994a).

Langdon, C. (2010). Determination of dissolved oxygen in seawater by Winkler 
    titration using the amperometric technique. The GO-SHIP Repeat 
    Hydrography Manual A Collection of Expert Reports and Guidelines E. M. 
    Hood, C. L. Sabine and B. M. Sloyan, IOCCP Report Number 14, ICPO 
    Publication Series Number 134.



Figure 1: Vertical section showing the detail of the oxygen field in the 
          upper 600 m of the water column.

Figure 2: Full depth vertical section of dissolved oxygen structure along 
          152W (P16N line).












DISSOLVED INORGANIC CARBON (DIC)

PI: Richard A. Feely and Rik Wanninkhof
Technicians: Robert Castle and Brendan Carter



Sample collection

Samples for DIC measurements were drawn (according to procedures outlined in 
the PICES Publication, Guide to Best Practices for Ocean CO2 Measurements) 
from Niskin bottles into 310 ml borosilicate glass flasks using silicone 
tubing. The flasks were rinsed once and filled from the bottom with care not 
to entrain any bubbles, overflowing by at least one-half volume. The sample 
tube was pinched off and withdrawn, creating a 6 ml headspace, followed by 
the addition of 0.12 ml of saturated HgCl2 solution, which was added as a 
preservative. The sample bottles were then sealed with glass stoppers lightly 
covered with Apiezon-L grease.


Equipment

The analysis was done by coulometry with two analytical systems (PMEL1 and 
PMEL2) used simultaneously on the cruise. Each system consisted of a 
coulometer (CM5015 UIC mc) coupled with a Dissolved Inorganic Carbon 
Extractor (DICE). The DICE system was developed by Esa Peltola and Denis 
Pierrot of NOAA/AOML and Dana Greeley of NOAA/PMEL to modernize a carbon 
extractor called SOMMA (Johnson et al. 1985, 1987, 1993, and 1999; Johnson 
1992).

The two DICE systems (PMEL1 and PMEL2) were set up in a seagoing container
modified for use as a shipboard laboratory on the aft main working deck of 
the R/V Ronald H. Brown.


Calibration Accuracy and Precision

The stability of each coulometer cell solution was confirmed three different 
ways.

  1) Gas loops were run at the beginning and end of each cell; 
  2) CRM's supplied by Dr. A. Dickson of SIO, were measured near the 
     beginning; and 
  3) Samples from the same Niskin were run throughout the life of the cell 
     solution.

Each coulometer was calibrated by injecting aliquots of pure CO2 (99.999%) by 
means of an 8-port valve (Wilke et al., 1993) outfitted with two calibrated 
sample loops of different sizes (1ml and 2ml). The instruments were each 
separately calibrated at the beginning of each cell with a minimum of two 
sets of these gas loop injections and then again at the end of each cell to 
ensure no drift during the life of the cell.

The accuracy of the DICE measurement is determined with the use of standards 
(Certified Reference Materials (CRMs), consisting of filtered and UV 
irradiated seawater) supplied by Dr. A. Dickson of Scripps Institution of 
Oceanography (SIO). The CRM accuracy is determined manometrically on land in 
San Diego and the DIC data reported to the database have been corrected to 
this batch 143 CRM value. The CRM certified value for this batch is 2017.75 
µmol/kg(^1).

The precision of the two DICE systems can be demonstrated via the replicate 
samples. Approximately 13% of the Niskins sampled were duplicates taken as a 
check of our precision.

These replicate samples were interspersed throughout the station analysis for 
quality assurance and integrity of the coulometer cell solutions. The average 
absolute difference from the mean of these replicates is 0.75 µmol/kg - No 
major systematic differences between the replicates were observed(^2)


Summary

The overall performance of the analytical equipment was good during the 
cruise. For the first four days, PMEL 2 was not working properly and samples 
from stations 115, 117 and 119 were bad. After replacing a bad lamp, a 
disconnected gas line was discovered during the analysis of samples from 
station 119. After fixing it, the rest of the samples from station 119 gave 
good results. Beginning with station 120, all Niskins were sampled and 
analyzed except for 3 Niskins from the close-spaced shelf stations.

Including the duplicates, over 2,400 samples were analyzed for dissolved 
inorganic carbon (DIC). With the loss of the three stations (115, 117 & 119) 
mentioned above and a slightly less than full profile on station 121, there 
is a DIC value for approximately 97% of the Niskins tripped. The DIC data 
reported to the database directly from the ship are to be considered 
preliminary until a more thorough quality assurance can be completed shore 
side.


Calibration data during this cruise:

UNIT   L Loop     S Loop     Pipette    Ave CRM(^1)    Std Dey(^1)  Dupes (^2)
-----  ---------  ---------  ---------  -------------  -----------  ----------
PMEL1  1.9842 ml  1.0006 ml  27.571 ml  2013.72, N=55  1.42         0.71
PMEL2  1.9885 ml  0.9857 ml  26.363 ml  2015.83, N=48  1.80         0.79



References

Dickson, A.G., Sabine, C.L. and Christian, J.R. (Eds.), (2007): Guide to Best 
    Practices for Ocean CO2 Measurements. PICES Special Publication 3, 191 
    pp.

Feely, R.A., R. Wanninkhof, H.B. Milburn, C.E. Cosca, M. Stapp, and P.P. 
    Murphy (1998): "A new automated underway system for making high precision 
    pCO2 measurements aboard research ships." Anal. Chim. Acta, 377, 185-191.

Johnson, K.M., A.E. King, and J. McN. Sieburth (1985): "Coulometric DIC 
    analyses for marine studies: An introduction." Mar. Chem., 16, 61-82.

Johnson, K.M., P.J. Williams, L. Brandstrom, and J. McN. Sieburth (1987): 
    "Coulometric total carbon analysis for marine studies: Automation and 
    calibration." Mar. Chem., 21, 117-133.

Johnson, K.M. (1992): Operator's manual: "Single operator multiparameter 
    metabolic analyzer (SOMMA) for total carbon dioxide (CT) with coulometric 
    detection." Brookhaven National Laboratory, Brookhaven, N.Y., 70 pp.

Johnson, K.M., K.D. Wills, D.B. Butler, W.K. Johnson, and C.S. Wong (1993):
    "Coulometric total carbon dioxide analysis for marine studies: Maximizing 
    the performance of an automated continuous gas extraction system and 
    coulometric detector." Mar. Chem., 44, 167-189.

Lewis, E. and D. W. R. Wallace (1998) Program developed for CO2 system 
    calculations. Oak Ridge, Oak Ridge National Laboratory. 
    http://cdiac.oml.gov/oceans/co2rprt.html

Wilke, R.J., D.W.R. Wallace, and K.M. Johnson (1993): "Water-based 
    gravimetric method for the determination of gas loop volume." Anal. Chem. 
    65, 2403-2406








DISCRETE pH ANALYSES

PI: Dr. Andrew Dickson
Cruise Participant: Michael B. Fong



Sampling

Samples were collected in 250 mL Pyrex glass bottles and sealed using grey 
butyl rubber stoppers held in place by aluminum-crimped caps. Each bottle was 
rinsed two times and allowed to overflow by one additional bottle volume. 
Prior to sealing, each sample was given a 1% headspace and poisoned with 
0.02% of the sample volume of saturated mercuric chloride (HgCl2). Samples 
were collected only from Niskin bottles that were also being sampled for both 
total alkalinity and dissolved inorganic carbon in order to completely 
characterize the carbon system. This resulted in an overall coverage of 
greater than 75%. Additionally, two duplicate samples were collected from 
each station for quality control purposes.


Analysis

pH was measured spectrophotometrically on the total hydrogen scale using an 
Agilent 8453 spectrophotometer and in accordance with the methods outlined by 
Carter et al., 2013. A Kloehn V6 syringe pump was used to autonomously fill, 
mix, and dispense sample through the custom 10cm flow-through jacketed cell. 
A Thermo NESLAB RTE-7 recirculating water bath was used to maintain the cell 
temperature at 25.0°C during analyses, and a YSI 4600 precision thermometer 
and probe were used to monitor and record the temperature of each sample 
immediately after the spectrophotometric measurements were taken. The 
indicator meta-cresol purple (mCP) was used to measure the absorbance of 
light measured at two different wavelengths (434 nm, 578 nm) corresponding to 
the maximum absorbance peaks for the acidic and basic forms of the indicator 
dye. A baseline absorbance was also measured and subtracted from these 
wavelengths. The baseline absorbance was determined by averaging the 
absorbances from 725-735nm. The ratio of the absorbances was then used to 
calculate pH on the total scale using the equations outlined in Liu et al., 
2011. The salinity data used was obtained from the conductivity sensor on the 
CTD. The salinity data was later corroborated by shipboard measurements.


Reagents

The mCP indicator dye was made up to a concentration of approximately 2.0mM 
and a total ionic strength of 0.7 M. A total of 4 batches were used during 
Leg 2 of the cruise. The pHs of these batches was adjusted with 0.1 M 
solutions of HCl and NaOH (in 0.6 M NaC1 background) to approximately 7.5-
7.8, measured with a pH meter calibrated with NBS buffers. The indicator was 
purified using the HPLC technique described by Liu et al., 2011.


Data Processing

An indicator dye is itself an acid-base system that can change the pH of the 
seawater to which it is added. Therefore it is important to estimate and 
correct for this perturbation to the seawater's pH for each batch of dye used 
during the cruise. To determine this correction, multiple bottles from each 
station were measured twice, once with a single addition of indicator dye and 
once with a double addition of indicator dye. The measured absorbance ratio 
(R) and an isosbestic absorbance (Aiso) were determined for each measurement, 
where:

    R = ((A578)-A(base)) / ((A(434) - A(base)) and

    A(iso) = ((A(488) - A(base)).

The change in R for a given change in A(iso), was then plotted against the 
measured R-value for the normal amount of dye and fitted with a linear 
regression. From this fit the slope and y-intercept (b and a respectively) 
are determined by:

    ∆R/∆A(iso) = bR + a

From this the corrected ratio (R') corresponding to the measured absorbance 
ratio if no indicator dye were present can be determined by:

    R' = R - A(iso) (bR + a)


Standardization/Results

The precision of the data was accessed from measurements of duplicate 
analyses, replicate analyses (two successive measurements on one bottle), 
certified reference materials (CRMs) from Batch 143 (provided by Dr. Andrew 
Dickson, UCSD), and TRIS buffer Batch 26 (provided by Dr. Andrew Dickson, 
UCSD). CRMs were measured twice a day and bottles of TRIS buffer were 
measured about twice a week over the course of the cruise.

The overall precision determined from duplicate analyses was ±0.00039 
(n=185). The overall precision determined from replicate analyses was 
±0.00056 (n=187). Additionally, 108 measurements were made on 54 bottles of 
Certified Reference Materials and found to have a pH of 7.9201 ±0.0018 
(n=108) and a within-bottle standard deviation of ±0.0005 (n=54). 
Furthermore, 20 measurements were made on 11 bottles of TRIS buffer solution 
and the pH was found to be 8.0913 ±0.0017 (n=20).


Problems

The high standard deviation of the TRIS pH's appear to be due to unusually 
high and low values measured on two days. If data from these two days are 
removed, the standard deviation improves to 0.0007. The temperature of the 
system appeared to be in control. Further investigation will be required to 
determine the cause of the unstable TRIS pH's.

Some of our bottles were quite fragile and cracked from the warming and 
expansion of the sample after collection. This resulted in the loss of a few 
samples. Some bottles also broke at the neck when crimping and sealing the 
sample.

Typically, the precision from duplicates and replicates should be similar and 
around ±0.0004. However, the replicate precision from Leg 2 was slightly high 
and greater than the duplicate precision. The poorer replicate precision 
seemed to be caused by a handful of measurements with extremely poor 
repeatability (exceeding the control limit of 0.0017 difference in replicate 
measurements). Most of these outliers were from samples with low pH (<7.6), 
and the second measurements almost always had a higher pH. This might suggest 
that some CO2 loss occurred, despite precautions to minimize gas exchange 
(i.e., threading the sampling tube through a rubber stopper so that the 
bottle can be capped during measurement). I tried inverting the bottles a few 
times prior to opening to evenly distribute any gradients that might exist in 
the bottles. It is unclear whether this helped.

Our HgCl2 dispenser became clogged towards the end of the cruise, and we were 
unable to unclog it. We therefore poisoned our samples using the DIC group's 
supply of HgCl2. The DIC group dispenses 120 µL of HgCl2 into their samples 
as opposed to the 60 µL we use for our samples. Our samples from Station 187 
onwards were poisoned with double our usual amount of HgCl2.



References

Carter, B.R., Radich, J.A., Doyle, H.L., and Dickson, A.G., "An Automated 
    Spectrometric System for Discrete and Underway Seawater pH Measurements," 
    Limnology and Oceanography: Methods, 2013.

Liu, X., Patsvas, M.C., Byrne R.H., "Purification and Characterization of 
    meta Cresol Purple for Spectrophotometric Seawater pH Measurements," 
    Environmental Science and Technology, 2011.





DISCRETE pH ANALYSES-"pH Dye"

PI: Dr. Andrew Dickson
Cruise Participant: Michael B. Fong



In addition to the regular 250 mL pH samples, one 500 mL sample was collected 
every station from a random Niskin. A larger volume sample was collected so 
that up to four pH measurements at different indicator dye concentrations can 
be made on a single bottle. The purpose of these samples was to gather more 
data to better characterize the perturbation effects of the dye on the sample 
pH.

The "pH Dye" samples were collected in a used CRM bottle (500 mL glass 
bottle) with a ground glass stopper, sealed with grease and secured with a 
band and clip. Initially, these samples were not collected according to 
standard pH sampling procedures. Instead, the bottles were merely filled with 
water. Toward the end of the cruise, when we were confident that there was 
sufficient water in the Niskins, the pH Dye samples were collected according 
to standard pH protocolrinsing twice and overflowing the bottle by one 
volume. The headspace was adjusted by pipetting off the excess water with an 
Eppendorf pipette (as is done with the pH samples), and the samples were 
poisoned with twice the amount of HgCl2 used for the 250 mL pH samples. The 
samples were measured spectrophotometrically, following the same procedures 
described in the Discrete pH Analyses section.

The data reported for pH Dye samples are not dye-corrected and are simply 
reported as the average of the four measurements on a single bottle.


Problems:

The pH of the pH Dye samples are not always comparable to the values measured 
in the 250 ml, samples. Even in the samples collected following standard pH 
protocol, the difference between the pH Dye and regular pH samples can be as 
large as 0.003. This was probably due to the difficulty in adjusting the 
headspace. Using the same size pipette as for the regular pH samples, it was 
necessary to pipette multiple times to achieve a 1% headspace, but this was 
not always reproducible.





P16N Leg 2 - 2015 - TOTAL ALKALINITY

PI: Andrew G. Dickson - Scripps Institution of Oceanography
Technicians: David Cervantes and August Pereira


Total Alkalinity

The total alkalinity of a sea water sample is defined as the number of moles 
of hydrogen ion equivalent to the excess of proton acceptors (bases formed 
from weak acids with a dissociation constant K 10-4.5 at 25°C and zero ionic 
strength) over proton donors (acids with K> 10-4.5) in 1 kilogram of sample.


Total Alkalinity Measurement System

Samples were dispensed using a Sample Delivery System (SDS) consisting of a 
volumetric pipette, various relay valves, and two air pumps controlled by 
LabVIEW 2012. Before filling the jacketed cell with a new sample for 
analysis, the volumetric pipette was cleared of any residual from the 
previous sample with the aforementioned air pumps. The pipette was then 
rinsed with new sample and filled, allowing for overflow and time for the 
sample temperature to equilibrate. The sample bottle temperature was measured 
using a DirecTemp thermistor probe inserted into the sample bottle. The 
volumetric pipette temperature was measured using a DirecTemp surface probe 
placed directly on the pipette. These temperature measurements were used to 
convert the sample volume to mass for analysis.

Samples were analyzed using an open cell titration procedure using two 250 mL 
jacketed cells. One sample was undergoing titration while the second was 
being prepared and equilibrating to 20°C for analysis. After an initial 
aliquot of approximately 2.3-2.4 mL of standardized hydrochloric acid ('0.1M 
HCl in '0.6M NaC1 solution), the sample was stirred for 5 minutes while air 
was bubbled into it at a rate of 200 scc/m to remove any liberated carbon 
dioxide gas. A Metrohm 876 Dosimat Plus was used for all standardized 
hydrochloric acid additions. After equilibration, 19 aliquots of 0.04 ml were 
added. Between the pH range of 3.5 to 3.0, the progress of the titration was 
monitored using a pH glass electrode/reference electrode cell, and the total 
alkalinity was computed from the titrant volume and e.m.f. measurements using 
a nonlinear least-squares approach (Dickson, et.al., 2007). An Agilent 34970A 
Data Acquisition/Switch Unit with a 34901A multiplexer was used to read the 
voltage measurements from the electrode and monitor the temperatures from the 
sample, acid, and room. The calculations for this procedure were performed 
automatically using Lab VIEW 2012.


Sample Collection

Samples for total alkalinity measurements were taken at all P16N Leg 2 
Stations (113-207). All 24 Niskin bottles were sampled for analysis whenever 
possible. For every 12 Niskin bottles, one duplicate sample was taken for 
quality control analyses. Using silicone tubing, the total alkalinity samples 
were drawn from Niskin bottles into 250 mL Pyrex glass bottles, making sure 
to rinse the bottles and Teflon sleeved glass stoppers at least twice before 
the final filling. A headspace of approximately 5 mL was removed and 0.06 mL 
of saturated mercuric chloride solution was added to each sample for 
preservation. After sampling was completed, each sample's temperature was 
equilibrated to approximately 20°C using a Thermo Scientific RTE water bath.


Problems and Troubleshooting

During instrument set up for Leg 2, it was discovered that the Pipette A SDS 
board was dispensing less than the calibrated volume that was determined back 
on shore. This was confirmed by running titrations using a calibrated manual 
pipette to dispense reference seawater of known total alkalinity and 
measuring the correct total alkalinity. The Pipette A SDS board was providing 
incorrect total alkalinity values with the same reference seawater. As a 
result, a volume correction was applied to the Pipette A SDS board (from 
92.946 mL to 92.853 mL) to account for the shift in its dispensing volume. 
After this correction was made, the CRM average remained precise and accurate 
for the remainder of the cruise (see Quality Control section for Reference 
Material data).

About one week into Leg 2, communication issues began to occur with our 
instruments. The computer was failing to consistently communicate with the 
Dosimat and therefore not adding acid when commanded by the computer. This 
eventually led to replacement of the NI USB 6501 box that connects the 
Dosimat to the computer. One week later, the computer began failing to 
recognize and communicate with the Agilent 34970A Data Acquisition/Switch 
Unit. The Switch Unit was replaced but produced the same result. Once the 
computer was replaced, all instrumental communication issues ceased for the 
remainder of the cruise.

0.06 mL of saturated mercuric chloride solution is normally added to each 
250mL sample for preservation. On Station 186, the Dispensette succeeded to 
dispense mercuric chloride for samples 1-5 but failed for the rest of the 
station. After sample 5, the Dispensette from the DIC group was used. This 
new Dispensette delivered 0.120 mL instead of 0.06 mL. After some minor 
cleaning, the TA Dispensette began working properly to begin Station 187. 
However, this only lasted for the first three samples and the DIC provided 
Dispensette (and mercuric chloride volume) was used for the remainder of Leg 
2. Mercuric chloride volume corrections were applied to all samples for the 
accurate amount of mercuric chloride added.

2160 total alkalinity values were submitted out of 2162 sampled Niskin 
bottles. While analyzing samples from Station 122, there was an SDS 
malfunction and sample 9 was lost. SDS Pipette Board A continued to draw from 
bottle 9 without stopping like it normally would. By the time this was 
noticed by the analyst, not enough sample remained in the bottle for 
measurement. In addition, the Dosimat communication issue mentioned above 
resulted in the loss of sample 16 from Station 139. Therefore, no total 
alkalinity values are reported for these two samples and each is flagged as a 
5.


Quality Control

Dickson laboratory Certified Reference Material (CRM) Batch 143 was used to 
determine the accuracy of the total alkalinity analyses. The certified total 
alkalinity value for Batch 143 is 2241.04 ± 0.84 µmol/kg-1. This reference 
material was analyzed 163 times throughout P16N Leg 2. The preliminary B l43 
measured value average for P16N Leg 2 is 2241.40 ± 1.10. A correction of 
0.99984 will be applied to all samples.

For every 'l2 Niskin bottles, one duplicate sample was taken for quality 
control analyses. A total of 186 Niskins were sampled for duplicate analyses 
and gave a pooled standard deviation of 0.92 µmol/kg-1.

Throughout P16N Leg 2, empty pre-weighed glass bottles with rubber stoppers 
and aluminum caps were filled with deionized water from the SDS and then 
crimped shut. These sealed bottles will be weighed again once they return to 
shore to detect any possible or suspected shifts in volume dispensing 
throughout the cruise that could have caused reference material, and 
therefore sample, value shifts.

All of the P16N 2015 station's total alkalinity measurements were compared to 
measurements taken from the neighboring P16N 2015 stations and the P16N 2006 
stations of similar if not identical coordinates.

2162 Niskin bottles were sampled for total alkalinity analyses. 2160 total 
alkalinity measurements were submitted. 2 samples were lost. Corrections have 
already been applied for the Certified Reference Material measurement 
comparison and also for the mercuric chloride volume additions. A normalized 
total alkalinity plot was analyzed to aid in identifying any possible bad 
measurements. Although most corrections have been made and it is unlikely 
that additional ones will need to be performed, this data should be 
considered preliminary since the correction for any shifts in total volume 
dispensed per sample has to be checked, confirmed and applied. This 
assessment cannot be accomplished until the pre-weighed bottles of filled 
deionized water are reweighed back on land. Attached is a plot of total 
alkalinity versus pressure for all of the stations occupying P16N Leg 2 2015.



Reference

Dickson, Andrew G., Chris Sabine and James R. Christian, editors, "Guide to 
    Best Practices for Ocean CO2 Measurements", Pices Special Publication 3, 
    IOCCP Report No. 8, October 2007, SOP 3b, "Determination of total 
    alkalinity in sea water using an open-cell titration"
    







CARBON ISOTOPES IN SEAWATER (14/13C)

PI: Ann McNichol
Samplers: Bryan Kaiser, Zoe Sandwith, Maria Arroyo



Along the 152°W line, a total of 516 samples were collected from 26 stations, 
plus 6 duplicate samples. At 18 of the stations, the full profile was 
sampled; at 6 of the stations, samples were collected from σΘ ≈ 27.2 to the 
bottom of the mixed layer, plus the surface Niskin. During the Alaskan Gyre 
transect, the surface Niskin was sampled at every station. Samples were 
collected in 500 mL airtight glass bottles.

Using silicone tubing, the flasks were overflowed 1.5 times the fill time 
with seawater from the Niskin bottle while keeping the tubing at the bottom 
of the flask. Once the sample was taken, 5-10 ml of water was poured off to 
create a headspace and 120 µL saturated mercuric chloride solution was added 
in the sampling bay. In order to avoid contamination, gloves were used during 
all collection, handling, and storage processes. Sample handling was done on 
a clean table covered with plastic. After all samples were collected from a 
station, the glass stoppers were dried and greased with Apiezon-M grease to 
ensure an airtight seal. The stoppers were secured with a rubber band. The 
samples were stored in AMS boxes inside the ship's bio-analytical laboratory 
during the cruise, then transferred to the WHOI shipping container at the end 
of the leg. The samples will be shipped to WHOI for analysis. The 
radiocarbonlDlC content of seawater (DI 14C) is measured by extracting the 
inorganic carbon as CO2 gas, converting the gas to graphite, then counting 
the number of 14C atoms in the sample directly using an accelerator mass 
spectrometer (AMS). Radiocarbon values will be reported as 14C using 
established procedures modified for AMS applications. The 13C/12C of the CO2 
extracted from seawater is measured relative to the 13C/12C, a CO2 gas 
standard calibrated to the PDB standard using an isotope radio mass 
spectrometer (IRMS) at NOSAMS.







DISSOLVED ORGANIC CARBON (DOC)

PI: Dennis Hanseil
Sampler: Benjamin Granzow


Dissolved Organic Carbon (DOC) samples were taken from every Bullister (aka 
Niskin) bottle at every other station (odd stations). Samples were also taken 
from stations 130, 148, 188, and 195-207. Duplicates were taken on the first 
(deepest) 12 bottles on every station except for stations 185-189 and 
stations 204-207. 1936 samples were taken from 57 stations in total. All 
samples from depths of 300m and shallower were filtered through GF/F filters 
using in-line filtration. Samples from deeper depths were not filtered. 
Samples were taken in polycarbonate 60 ml bottles and duplicates were taken 
in 4OmL glass vials. The polycarbonate bottles were precleaned with 10% HCl 
and rinsed with Mili-Q water. Both the glass duplicate vials and GF/F filters 
were combusted a 450°C overnight. Filter holders and silicone tube were 
cleaned with 10% HCl and rinsed with Mili-Q water before sampling.

Bottles were rinsed three times with the seawater before collecting 50 - 60 
ml, of sample at each Bullister bottle. Duplicate vials were rinsed three 
times with seawater before collecting 30 - 40 ml, of sample from the first 
twelve Bullister bottles. Additionally, atmospheric blanks were collected on 
stations 113, 177, and 200. To collect these blanks, 50 ml, of Mili-Q water 
were placed in a 60 ml, polycarbonate bottle and left uncapped during 
sampling. The blank was capped at the end of the sampling and frozen.

Samples taken in polycarbonate were frozen upright for 18 hours before being 
put into bags labeled by station. Duplicate vials were stored in boxes at 
room temperature in the dark. The frozen samples and duplicates were shipped 
back to The Rosenstiel School of Marine and Atmospheric Science in 4 coolers 
and 5 crates for laboratory analysis by High Temperature Combustion (HTC). 
Gloves were used during all processes of collection, and all samplers taking 
water at the rosette prior to DOC wore gloves.

Problems: While sampling we would encounter grease on some Niskin spigots, 
which would dirty the ends of the tubing used. Each dirty spigot was wiped 
with Kimwipes before sampling. Dirty tubes were replaced before the next 
station.





CLIVAR P16N Leg 2

DISSOLVED ORGANIC CARBON 14C, BLACK CARBON 14C, ULTRAFILTERED DISSOLVED 
ORGANIC CARBON 14C

PI: Ellen R.M. Druffel, Earth System Science, University of California, 
    Irvine
Sample Collection: Brett D. Walker, Earth System Science, University of 
    California, Irvine.



7x Black Carbon and 56x lL total DO14C and 4x ultrafiltered DO14C samples 
were taken. Samples were taken at 10 stations on Leg 2 of the P16N cruise. 
Stations sampled were #128 (30°N, l52°W), #129 (30.5°N, l52°W), #130 (30°N, 
l52°W), #154 (43°N, l52°W), #155 (43.5°N, l52°W), #174 (53°N, l52°W), #175 
(53.5°N, l52°W), #181 (55.5°N, l52°W), #204 (56.5°N, l37.5°W) and #205 
(56.5°N, l36°W).


Project Summary:

DOC is the largest pool of organic carbon in the ocean, comparable to the 
total carbon content in the atmosphere. Knowing the carbon isotopic 
signatures of DOC is important for understanding the biogeochemistry and 
dynamics of DOC cycling, and is essential for the C cycle modeling community. 
This study addresses fundamental gaps in our knowledge of the global carbon 
cycle and the dynamic nature of DOC in the ocean. These results will provide 
much needed, quantitative information on the timescale of DOC cycling in the 
ocean. These results will also help to determine the amount of terrestrially 
derived organic carbon (e.g. black carbon) in the open ocean. DOC may serve 
as a sink for excess carbon dioxide produced from fossil fuel and biomass 
burning. Most of this excess carbon will end up in the ocean, and it is 
critical to improve our understanding of the processes that are important for 
its long-term storage. Results of this research will be made available for 
use in models that assess present and future concentrations of atmospheric 
CO2.

The average radiocarbon (14C) age of dissolved organic carbon (DOC) in the 
deep ocean ranges from 4000 - 6500 14C years. However, the data set used to 
estimate this range is based on only a few sites in the world ocean. The main 
objective of this research is to determine the 14C signatures of DOC in 
seawater from low and high latitude regions of the Pacific for which there is 
no data. High-precision A 14C measurements will be performed on samples using 
AMS (accelerator mass spectrometry) of DOC in water samples from detailed 
profiles at each site. Another objective of this effort is to isolate black 
carbon from DOC and determine the 14C and 13C signatures of this recalcitrant 
DOC fraction. As a test we are also collecting 4x samples of size-
fractionated DOC to determine the size-age structure of DOC in the ocean. We 
are testing three hypotheses:

    (1) 14C of bulk DOC in the low latitude regions of the Pacific Ocean are 
        similar to those in the south and north Pacific.

    (2) Black carbon constitutes a significant amount of DOC in open ocean 
        water, and its 14C age is greater than 10,000 14C years.

    (3) Ultrafiltered DO14C will reveal the molecular size-age structure of 
        the DOC pool in the ocean.





DISSOLVED ORGANIC CARBON-14 SAMPLING AND ANALYSIS

Dissolved organic carbon-14 samples were taken in pre-combusted 
(540°C/4hours) 1L borosilicate bottles (amber boston round). We collected 7x 
DOC samples below 1000m and 7x samples above 1000m at each station. Samples 
above 400m depth were filtered using precombusted GFF filters and acid 
cleaned silicone tubing/stainless steel filter manifolds. Samples were 
immediately frozen after collection and stored at -20°C until analysis at 
UCI. Once in the lab, CO2 will be evolved from DOC via UVoxidation and vacuum 
line extraction. This CO2 will then be graphitized and its radiocarbon 
content measured via accelerator mass spectrometry at the KCCAMS facility at 
UCI.

Size fractionated (ultrafiltered) DOC was collected from the surface (<20m) 
and deep (3000m) depths from 2x stations along the transect. Collection and 
analysis is identical to that for DO 14C, except 1L seawater volumes will be 
ultrafiltered in the lab prior to 14C analysis.


Black Carbon-14 Sampling

Due to extremely low concentrations of Black carbon in seawater (<5% of the 
DOC pool), 4x 4 gallon filtered surface samples were collected from stations 
#128-129, 154, 174 204, while 3x 8 gallon deep samples were collected from 
stations #128-129, 154, and 204/205. The concentration and carbon isotopes 
(14C and '3C) of black carbon in this sample (and all others collected from 
Repeat Hydrography cruises) will be measured using the benzene polycarboxylic 
acid (BPCA) method, and these data will be used to estimate the abundance and 
source of black carbon in oceanic DOC. Individual BPCAs will be isolated 
using a preparative column gas chromatograph (PCGC). These fractions will be 
combusted to CO2 gas, graphitized and radiocarbon content measured.


Potential Contamination Issues:

Several observations were made on Leg 2 that could possibly influence our 
natural abundance DOC D14C measurements, and DOM measurements from other 
groups (UCSB: CDOM, and UM: DOC/TN). These are summarized below:

    1) Wire grease in the form of large oil slick plumes were observed 
       immediately after using StranCore at Station 148. These plumes were 
       documented to be present during casts for at least 1.5 weeks. Samples 
       were taken to evaluate the presence of StranCore grease in seawater 
       samples, which may contribute gross isotopic contamination of our 
       surface and deep samples.

    2) Leaking Z-drive also input significant hydrocarbon oils into the 
       surface ocean near the ship and rosette.

    3) Anomalous foaming bubbles (grey water discharge?) were present for 
       several days if not one week surrounding the ship. This could also 
       have potentially contaminated our surface samples.

Unlike Leg 1, no grease was observed to be present on the Niskin bottles at 
least during the stations we sampled. All science parties were exceptionally 
vigilant in their use of cleaned Si02 tubing to sample the rosette. 
Preliminary tests of DOC concentrations from Leg 1 suggest that the wire 
grease is not an immediate issue, however, our isotopic D14C are far more 
sensitive and future testing will be required to see if our samples have been 
compromised. We recommend in the future that wire grease be applied at the 
end of the cruise, or immediately after a DO 14C station (of which there were 
only four on Leg 2) to minimize impact on our scientific program.







P16N CRUISE REPORT FOR NUTRIENTS


Equipment and Techniques

Dissolved nutrients (phosphate, silicate, nitrate and nitrite) were measured 
by using a Seal Analytical AA3 HR automated continuous flow analytical system 
with segmented flow and colormetric detection.


Detailed methodologies are described by Gordon et al. (1992).

Silicic acid was analyzed using a modification of Armstrong et al. (1967). An 
acidic solution of ammonium molybdate was added to a seawater sample to 
produce silicomolybic acid. Oxalic acid was then added to inhibit a secondary 
reaction with phosphate. Finally, a reaction with ascorbic acid formed the 
blue compound silicomolybdous acid. The color formation was detected at 660 
mn. The use of oxalic acid and ascorbic acid (instead of tartaric acid and 
stannous chloride by Gordon et al.) were employed to reduce the toxicity of 
our waste steam.

Nitrate and Nitrite analysis were also a modification of Armstrong et al. 
(1967). Nitrate was reduced to nitrite via a copperized cadmium column to 
form a red azo dye by complexing nitrite with sulfanilamide and N-1 -
naphthylethylenediamine (NED). Color formation was detected at 540 mn. The 
same technique was used to measure nitrite, (excluding the reduction step).

Phosphate analysis was based on a technique by Bernhart and Wilhelms (1967). 
An acidic solution of ammonium molybdate was added to the sample to produce 
phosphomolybdate acid. This was reduced to the blue compound phosphomolybdous 
acid following the addition of hydrazine sulfate. The color formation was 
detected at 820 mn.


Sampling and Standards

Nutrient samples were drawn in 50m1 HDPE Nalgene sample bottles that had been 
stored in 10% HCl. The bottles are rinsed 3-4 times with sample prior to 
filling. A replicate was normally drawn from the deep Niskin bottle at each 
station for analysis to reduce carry over. Samples were then brought to room 
temperature prior to analysis. Fresh mixed working standards were prepared 
before each analysis. In addition to the samples, each analysis consisted of 
3 replicate standards, 3 DIW blanks and 3 Matrix blanks placed at the 
beginning and then repeated at the end of each run. Also, one mixed working 
standard from the previous analytical run was used at the beginning of the 
new run to determine differences between the two standards. Samples are 
analyzed from deep water to the surface. Low Nutrient Seawater (LNSW) was 
used as a wash, base line carrier and medium for the working standards.

The working standard was made by the addition of 0.2ml of primary nitrite 
standard and 15.0 ml of a secondary mixed standard (containing silicic acid, 
nitrate, and phosphate) into a 500ml calibrated volumetric flask of LNSW. 
Working standards were prepared daily.

Dry standards of a high purity were pre-weighed at PMEL. Nitrite standards 
were dissolved at sea. The secondary mixed standard was prepared by the 
addition of 3Oml of a nitrate - phosphate primary standard to the silicic 
acid standard. Nutrient concentrations were reported in micromoles per liter. 
Lab temperatures were recorded for each analytical run. All the pump tubing 
was replaced at least four times during the P16N cruise.

Approximately 2200 samples were analyzed.




Reference:

Armstrong, F.A.J., Steams, C.R. and Strickland, J.D.H. (1967) The measurement 
    of upwelling and subsequent biological processes by means of the 
    Technicon AutoAnalyzer and associated equipment. Deep-Sea Res. 14:381-
    389.

Bernhard, H. and Wilhelms, A. (1967) The continuous determination of low 
    level iron, soluble phosphate and total phosphate with AutoAnalyzer. 
    Technicon Symposia, I. pp.385-389.

Gordon, L.I., Jennings Jr., J.C., Ross, A.A. and Krest, J.M. (1993) A 
    suggested protocol for the continuous automated analysis of seawater 
    nutrients (phosphate, nitrate, nitrite and silicic acid) in the WOCE 
    Hydrographic program and the Joint Global Ocean Fluxes Study, WOCE 
    Operations Manual, vol. 3: The Observational Programme, Section 3.2: WOCE 
    Hydrograghic Programme, Part 3.1.3: WHP Operations and Methods. WHP 
    Office Report WHPO 91-1; WOCE Report No. 68/91. November 1994, Revision 
    1, Woods Hole, MA., USA, 52 loose-leaf pages.







DISCRETE SALINITY SAMPLING


Preparation

Two Guildline Autosal's, model 8400B salinometers (S/N 61668, nicknamed 
Dallas and S/N 60555, nicknamed Debbi), located in the salinity analysis 
room, were used for all salinity measurements. The salinometer readings were 
logged on a computer using Ocean Scientific International's logging hardware 
and software. The Autosal's water bath temperature was set to 24°C, which the 
Autosal is designed to automatically maintain. The laboratory's temperature 
was also set and maintained to 23°C, to help further stabilize reading values 
and improve accuracy. The temperature of the room was monitored by a 
thermostat as well as spot checked daily with a handheld thermistor to 
confirm accuracy of the unit and verify that the room was staying at or below 
24°C. Salinity analyses were performed after samples had equilibrated to 
laboratory temperature. After spot checking sample temperatures using a 
thermistor probe, it was concluded that the wait time for this particular 
cruise for samples to come up to temperature should be around 24 hours 
because of the colder nature of the sampled water. The salinometer was 
standardized for each group of samples analyzed (usually 2 casts and up to 52 
samples) using two bottles of standard seawater: one at the beginning and end 
of each set of measurements. The salinometer output was logged to a computer 
file. A accessory peristaltic pump was used inline with the normal sample 
introduction tubing to draw the sample water from the sample bottle during 
analysis. The software prompted the analyst to flush the instrument's cell 
and change samples when appropriate. Prior to each run a sub-standard flush, 
approximately 200 ml, of the conductivity cell was conducted to flush out the 
DI water used in between runs. For each calibration standard, the salinometer 
cell was initially flushed 6 times before a set of conductivity ratio reading 
was taken. For each sample, the salinometer cell was initially flushed at 
least 3 times before a set of conductivity ratio readings were taken.

IAPSO Standard Seawater Batch P-157 was used to standardize all casts up to 
station 196 and the remaining stations used Batch P-155.


Sampling

The salinity samples were collected in 200 ml Kimax high-alumina borosilicate 
bottles that had been rinsed at least three times with sample water prior to 
filling. The bottles were sealed with custommade plastic insert thimbles and 
Nalgene screw caps. This assembly provides very low container dissolution and 
sample evaporation. Prior to sample collection, inserts were inspected for 
proper fit and loose inserts replaced to insure an airtight seal. PSS-78 
salinity [UNES81] was calculated for each sample from the measured 
conductivity ratios. The offset between the initial standard seawater value 
and its reference value was applied to each sample. Then the difference (if 
any) between the initial and final vials of standard seawater was applied to 
each sample as a linear function of elapsed run time. The corrected salinity 
data was then incorporated into the cruise database. Two duplicate samples 
were drawn from each cast to determine total analytical precision. When 
duplicate measurements were deemed to have been collected and run properly, 
they were averaged and submitted with a quality flag of 6. On P16N, 2384 
salinity measurements were taken, including 188 duplicates, and approximately 
110 vials of standard seawater (SSW) were used.


Analysis

The running standard calibration values and duplicates are below. Through the 
course of the 33 day cruise, the autosal standards changed by 0.00 12 in 
conductivity ratio, about 0.024 in salinity for Dallas and 0.0003 in 
conductivity ratio, about 0.005 in salinity for Debbi (Figure 1). The 
duplicates taken during the cruise showed a median precision of 2.24 x 10-4 
+1- 0.0016 psu (Figure 2).


Problems

Dallas showed small gradual increase in variability and instability through 
the first 48 stations and was swapped out for Debbi at station 161, which 
showed better stability.


Figure 1: Standard vial calibrations throughout the cruise.

Figure 2: Salinity residuals of the duplicate samples.







GO-SHIP P16N CESIUM SAMPLING 

(PI) Alison Macdonald 
(Sampler) Steven Pike 



The goal of this project is to investigate the pathways, mixing and transport 
of water in the North Pacific Ocean. In particular, we are seeking to 
understand the timescales associated with the gyre transport of water mixed 
down by winter storms in the western Pacific, as well as mixing and 
dispersion along the transport pathways as observed using the radionuclide 
tracers 137Cs (~30 year half-life) and 134Cs (2 year half-life).

Sampling: Each sample is taken in a 20 L plastic cubitainer. The cubitainers 
were filled with unfiltered seawater (<0.1% of Cs is particulate). No rinsing 
was required. As the samples are so large, all samples come from multiple 
Niskins. Each cubitainer is approximately 10 inches tall - making each 0.5" 
of water equivalent to 1 L. For the integrated samples drawn from multiple 
Niskin's the height of the water after the addition of water from each Niskin 
was recorded so that later the fraction from each pressure contributing to 
the sample could be ascertained.

On leg 2 there were five different types of samples taken (each sample = 1 
cubitainer):

    1) Integrated upper layer samples from Niskins within the range: ~100 - 
       300 dbar
    2) Integrated deeper samples taken within the range: ~300 - 600 dbar
    3) Profiles to ~1000 m with 12 samples (sample= 2 Niskins fired at the 
       same pressure)
    4) Shorter integrated profiles made up of left over water from multiple 
       Niskins in varying pressures ranges above 1000 dbar.
    5) Seawater Intake Surface samples (SIS)
       • 15 Upper layer (type 1) samples were taken at stations: 116, 124, 130,  
         136, 144, 152, 160, 168, 176, 184, 192, 194, 197, 200 and 202.
       • 15 Deeper (type 2) samples were taken at stations: 119,126,132, 140, 
         148, 156, 164, 172, 180, 186, 193, 196, 198,201 and 204.
       • 20 Cesium-only Profiles with 12 samples each were taken at stations: 
         113, 121, 128, 134, 148, 142, 146, 150, 154, 158, 162, 166, 172, 176, 
         182, 191, 195, 199, 203.
       • 29 Integrated profile samples (type 4) were taken at 6 stations: 187, 
         188, 189, 204, 206 and 207.
       • 71 SIS samples were taken (type 5) were drawn; one at each station 
         sampled using types 1-4, and 15 SIS samples drawn along our cruise 
         track (outside the Canadian EEZ) on our return to Seattle.
       • All told 370 cesium samples were drawn on Leg 2.

Some of the cesium samples were stored; others were filtered to reduce the 
volume of water shipped back to the lab where analysis will occur. To filter, 
the sample water was pumped slowly through a 5-ml volume KNiFC-AMP resin 
column. The resin is transferred to a counting vial for analysis in one of 
several high purity germanium well detectors at WHOI. Time was the main 
factor limiting the amount of filtering that could occur onboard. While in 
port in Hawaii, the 27 Leg 1 samples were filtered. On Leg 2, half of the 
samples from the cesium-only cast profiles (type 3) were filtered, the other 
half of the samples were stored. All upper layer, deeper layer and SIS 
(1,2,5) samples were stored unfiltered. Subsamples of some the unfiltered 
waters will later be used to analyze for (^129)I and (^90)Sr as well as the 
primary isotopes, (^134)Cs and (^137)Cs.

A set of staggering schemes for varying the pressures at which cesium profile 
samples were taken was used in a rotation of 3. The filtered and unfiltered 
samples were also staggered. For each set of 6 cesium casts the pressuresat 
which the Niskins were fired, the bottles that go into each sample, and 
whether the samples are filtered (F) or not (U), is described in Tables l-3.


Table 1: Sampling scheme for first 6 stations. In the columns following the 
         pressures F implies that the sample will be filtered, U implies that 
         samples will be stored in the cubitainer, unfiltered. Station 7 will 
         look like station 1, 8 like 2 etc.

Stagger ->  A           B           C           A           B           C
Niskins     Sta. 1      Sta. 2      Sta. 3      Sta. 4      Sta. 5      Sta. 6
----------  ----------  ----------  ----------  ----------  ----------  ----------
23-24        20      F   30      U    40     F   20      U   30      F    40     U
21-22        50      U   60      F    70     U   50      F   60      U    70     F
19-20        80      F   90      U   105     F   80      U   90      F   105     U
17-18       120      U  130      F   145     U  120      F  130      U   145     F
15-16       160      F  170      U   185     F  160      U  170      F   185     U
13-14       200      U  220      F   240     U  200      F  220      U   240     F
11-12       260      F  280      U   300     F  260      U  280      F   300     U
9-10        330      U  370      F   410     U  330      F  370      U   410     F
7-8         450      F  500      U   550     F  450      U  500      F   550     U
5-6         600      U  650      F   700     U  600      F  650      U   700     F
3-4         750      F  800      U   850     F  750      U  800      F   850     U
1-2         900      U  950      F  1000     U  900      F  950      U  1000     F
Intake      Surface  U  Surface  U  Surface  U  Surface  U  Surface  U  Surface  U


Table 2: Repeating scheme for Unfiltered samples for first 6 stations (subset 
         of Table 1).

A        B        C        A        B        C
Sta. 1   Sta. 2   Sta. 3   Sta. 4   Sta. 5   Sta.
Surface  Surface  Surface  Surface  Surface  Surface
-------  -------  -------  -------  -------  -------
 50       30        70      20       60       40
120       90       145      80      130      105
200      170       240     160      220      185
330      280       410     260      370      300
600      500       700     450      650      550
900      800      1000     750      950      850


Table 3: Repeating scheme for Filtered samples for first 6 stations (subset 
         of Table 1).

A       B       C       A       B       C
Sta. 1  Sta. 2  Sta. 3  Sta. 4  Sta. 5  Sta.
------  ------  ------  ------  ------  ----
 20      60      40      50      30       70
 80     130     105     120      90      145
160     220     185     200     170      240
260     370     300     330     280      410
450     650     550     600     500      700
750     950     850     900     800     1000







CHIPODS

PI: Jonathan Nash
Sampler: Bryan Kaiser



System Configuration and Sampling

Four Chipods were mounted on the rosette to measure temperature (T), its time 
derivative (dT/dt), and x and z (horizontal and vertical) accelerations at a 
sampling rate of 50 Hz. Two chipods were oriented such that their sensors 
pointed upward (circled in green in the figure below), and are referred to as 
uplookers. The other two pointed downwards and are referred to as downlookers 
(circled in green at the bottom of the rosette in the figure below). The 
chipod pressure case, containing the logger board and batteries, is circled 
in red in the figure below.

The uplooking sensors were positioned higher than the Niskin bottles on the 
rosette in order to avoid measuring turbulence generated by the firing of 
Niskin bottles. The downlooking sensors were positioned an inch above the 
base of the rosette at a distance of about six inches away from the frame. 
This ensured that the rosette could rest on its frame (and not on the 
downlooking sensors) and ensured that the downlooking sensors were as far 
from the frame as possible and as close to the leading edge of the rosette 
during descent as possible to avoid measuring turbulence generated by the 
rosette frame.


Data processing

To plot vertical profiles of turbulent kinetic energy dissipation (epsilon) 
and dissipation of thermal variance (chi), chipod temperature and temperature 
derivatives measurements must be collocated with pressure profiles. The 
chipods do not have a pressure sensors so vectors of doubly-integrated 
vertical acceleration (i.e. displacement) are fit to the pressure profiles 
from the CTD. Epsilon and chi as a function of pressure can be estimated by 
fitting the vertical temperature gradient (dT/dz) spectrum, computed using 
the temperature time derivative (dT/dt) and chipod descent rate, to the 
theoretical temperature gradient spectrum, by using an iterative procedure 
demonstrated by Moum and Nash (2009).

The figure below shows typical cast measurements from a downlooker. The high 
signal on the temperature derivative (dT/dt) record during the upcast is 
produced by the wake turbulence behind the rosette. The time record for the 
uplooker is similar; wake turbulence is recorded by the uplooker measurements 
as the rosette descends. However, there is a stronger wake turbulence signal 
for the uplooker because the uplooker sensors protrude beyond the top of the 
rosette frame. In addition, uplooker measurements on the upcast may be 
affected turbulence associated with the stops to fire the Niskin bottles.


Summary

The figure below shows a typical vertical profile of the turbulent kinetic 
energy dissipation (epsilon) and the dissipation of temperature variance as a 
function of pressure for both uplookers and downlookers. Both sets of 
profiles are of measurements at station 114 located at 23°N, and 152°W. In 
the profiles, local maximums near the surface indicate the presence of a weak 
mixed layer and weak mixing near the base of the summer thermocline (at 
approximately 800m), and a global maximum in the benthic boundary layer. In 
order to obtain better estimates, the data obtain from all four chipods at 
each station need to be considered together, and the rosette-generated 
turbulence must be filtered out of the signal. Therefore, further data 
processing is needed.


Known Problems

Chipods proved to be quite independent, and easy to manage during the cruise. 
There were, however, a couple of issues encounter during the cruise. These 
issues will be described in order of encounter frequency below, starting form 
the most common problem.


Mini-logger freezing when downloading data

A very common issue I found when working with Chipods came from the mini-
logger while recording data.

Symptom: The most common symptom was data recorded during the cast would look 
gibberish, unphysical. In the best-case scenario, the file would just read 
gibberish, but the Chipod would continue recording and the next files would 
look perfectly normal. The first time this happened was during the second 
cast. You will notice the casts 001-003 contain very little useful data. But 
starting from cast 004 and on they all looked good.

The worst-case scenario: Mini logger (program on laptop) would freeze and 
become non-responding. I would then force quit the program and in a couple of 
times, the Chipod would stop recording at all. The first time that this 
happen was on cast 024. 3 out of 4 chipods did the exact same thing. 
Solution: Over the course of the cruise, I found out that there were 
different ways to un-freeze the chipod. The most simple was to simply 
disconnect the Pressure case from the sensor. I don't know why, but it 
worked. In the absolute worst case scenario, where this didn't work and the 
Chipod would still be un-responsive, I remove the chipod from the CTD, opened 
it and removed the memory chip form the mini-logger board. After I put back 
the memory chip into its place, the Chipod then became responsive and began 
functioning normally.


CTD hitting bottom

This wasn't really common at all, but I feel it's a common situation, 
external to the Chipods. It hit once during our cruise, on station 027, going 
down at 60 m/min. I double checked everything, as I normally would do, and 
upong close inspection I found in the time record for the temperature 
derivative, there was a lot of noise, more so than in the downcast. I 
replaced both downlooking sensors for new ones. I wrote the Series number on 
the Chipod recovery logs, and you can find that info in the table below 
summarizing all changes made on the configuration of the Chipods.


Sensor Deterioration

Towards the end of the trip (cast 100 out of 112) significant sensor 
deterioration was observed in one of the Chipods (uplooking, SN2014). The 
symptom was values after looking at the SA output, for the values in the 
temperature derivative were very low (usually there are between 45000 and 
55000 when connected to a sensor, that time they were around 4200 and below). 
I changed both pressure case (along with its mini-logger SN2014 and 
everything inside) and put a new one. The values were equally low. Then I 
changed the sensor (thermistor) for a new one and the values came up 
significantly, no normal ones. While removing the thermistor (sensor) I 
noticed something like a white substance on it, possibly indicating 
corrosion. I didn't perform further tests on the Chipod SN2014. It may still 
very well be functional, since it looks like the problem was with the 
thermistor (uplooking sensor). The sensor holder, and the cables connecting 
the Chipod together were still the same.

At the last station, it looked like the other thermistor was showing the same 
signs: low values of the temperature and its derivatives when looking at the 
SA output. I did not change it. My recommendation is to have it replaced.


Chipods malfunction?

I replaced Chipod with Minilogger SN2013, towards the end of the cruise 
(stations 106112, which comprises two recoveries) for a new one, because it 
was giving me serious trouble when trying to connect to it. When connecting 
to it, through the Minilogger program, after hitting USB connect, the screen 
would then start displaying crazy symbols, not stop. It would not respond to 
anything, and just kept on displaying weird characters filling the screen, 
non-stop. I replaced the unit for a new one, the 4th replacement available 
with SN 2019. It turns out, however, that the new chipod unit (SN2019) did 
not record any file. All values displayed were working well, and it actually 
was bench tested by June and me in Papeete, but just wouldn't record 
anything. Being the last recovery when I realized that, I did not try to fix 
the problem since the cruise reached to an end. The Chipod unit is still 
mounted on the CTD.


CTD Malfunction promps interruption during cast

There were a few casts where the CTD, during a single cast, needed to be re-
booted in order to appropriately fire water bottles. This issue was external 
to the Chipods, but affected the amount of data that can be processed during 
the cruise. When this happened, the CTD would produce more than just one raw 
file (XXX.hex) for the same cast. The Chipod code used to process the data is 
written to read just one XXX.hex file and from there, determine the time 
interval (and date I guess) where the specific cast was done. In the 
situation where there are more than one file, the code doesn't work 
appropriately. The cast where this happen are: 033, 037 and 040. There are 
other (more common) cases where there are more than one xxx.hex ctd files, 
but where one of them was produced where the CTD was still onboard (prior a 
deployment). Such is the case, for example, of cast #111. In such cases, 
which are pretty common, I just used the 2 xxx.hex file for the same cast 
(that is the longest file). In such cases there is no problem.

Below is a table with all the info regarding the Chipod configuration used, 
along with the component's serial numbers. But first a little intro: In 
total, before sailing, we had 6 working chipods, with minilogger serial 
numbers listed below (2013, 2014, 2016, 2018, 2019, 2020). Unit SN 2020 was 
used to replaced a downlooking unit (when I mean unit, I mean the cylindrical 
pressure case with its own batteries and minilogger) just for cast 025 (unit 
with 5N2O 16, after most of the chipods froze), while trying to figure out a 
solution to the problem. Unit with minilogger 5N2O20 was then used again to 
replace an uplooker for good (unit with SN 2014) for the last casts 100-112.

Unit with SN2019 was used to replace unit with SN 2013, after this one went 
"crazy"!

This was done the last 6 casts, from 106-112.

In total three now sensors (thermistors) where replaced, although it is 
recommended that a 4th one (uplooker, connected to unit 2019) needs to be 
replaced.


   Logger Board  Pressure  Sensor    Sensor   Up/Down
        SN       Case SN     SN    Holder SN  looker   Cast used
   ------------  --------  ------  ----------  ------  ----------------
       2013       Ti44-7   14-26d      1        Up     001-106
       2014       Ti44-8   14-24d*     4        Up     001-099
       2016       Ti44-1   14-25d*     6       Down    001-024, 026-112
       2018       Ti44-3   11-25d*     2       Down    001-012
       2019       Ti44-6   14-26d*     1        Up     106-112
       2020       Ti44-5   14-28d      4        Up     100-112
       2020       Ti44-5   14-25d      6       Down    025


Several replacements were made during the cruise. For example, the Pressure 
case + logger board with serial numbers Ti44-1 and 2016 respectively, were 
replaced with the Pressure case + logger board with serial numbers Ti44-5 and 
SN 2020 respectively, during cast 025, oriented downwards. After the cast, 
the original configuration was mounted back again. Then after cast 099, the 
logger board (SN 2014), pressure case (Ti44-8) and sensor (SN 14-24d) were 
replaced with the logger board (SN 2020), pressure case (Ti44-5) and sensor 
(SN 14-28d), this time as an uplooker. That is why logger board SN 2020 
appears twice in the table. Similarly, the logger board SN 2013 and pressure 
case SN Ti44-7 were replaced by logger board SN2019 and pressure case SN 
Ti44-6 starting at cast 106.


Summary

Figure X shows a typical vertical profile of the turbulent kinetic energy 
dissipation (epsilon) and mean temperature as a function of pressure. The 
profile represents the cast 100, located at 16° 30 N, and 152° W. It can be 
appreciated that the there exists an absolute maximum near the base of the 
thermocline, and a local maximum near the bottom topography. These figures 
were made from the data coming from one of the downlooking Chipods. In order 
to obtain better estimates, the data obtain from all chipods at each station 
need to be consider together, taking into account whether the signal is 
coming from false turbulence, such as that produced in an uplooker at the 
downcast, or a downlooker in the upcast. For that, further processing needs 
to be applied to the data.



















2015 CLIVAR P16N leg 2 LADCP Cruise Report

D.C. McKee (LDEO; Participant), A.M. Thurnherr (LDEO; PI), and A. Stefanick 
(AOML)



Introduction

LADCP data were collected during the full-depth CTD cast at all stations. 
Additionally, LADCP data were collected during the secondary shallow casts 
for the cesium group until it became apparent that the back-to-back casts 
provided too much of a strain on the battery pack (data collected at stations 
121, 128, 134, 138). Preliminary processing and QC was performed onboard by 
McKee. Questionable profiles were sent to Thurnherr for shore-based 
processing and comparison of results. A full QC will be carried out after the 
cruise.


LADCP System Configuration

An AOML custom 48V lead acid rechargeable battery pack was used for all 
deployments. Instruments and battery pack were interfaced using a standard 
RDI star cable. Custom AOML deck leads were used for communications and 
charging between casts. The battery pack was periodically vented manually to 
prevent pressure build up. Battery power was periodically checked to ensure 
proper charge level of 52V was being maintained before deployments. Both the 
battery pack and the ADCP's were affixed to the CTD package using custom 
tabbed brackets aligned on horizontal cross-members of the package. The 
upward ADCP was positioned between niskin bottles 1 and 24 towards the outer 
ring, while the downward ADCP was affixed in the middle of the package about 
4 inches from the bottom ring. The configuration is shown in photo 01.

The power supply and data transfer were handled independently from any CTD 
connections. While on deck, a communications and power cable was connected to 
a cable in the staging bay that ran into the wet lab. This cable connected to 
a battery charger located in the wet lab for power and to an acquisitions 
computer via USB connection for data download. The LADCP acquisitions 
computer clock was synced to the master clock in the computer lab via 
network.


Table 01: Instruments used on cruise. DL = downlooker UL = uplooker.

    Model                Serial Number  Stations used
    -------------------  -------------  --------------------------
    Teledyne RDI WHM150  19394          113-117; 134-207 (DL)
    Teledyne RDI WHM300  13330          113-171 (UL)
    Teledyne RDI WHM300  12243          118-133 (DL); 172-207 (UL)


Three different ADCP instruments were used during this cruise (table 01). 
WHM150 #19394 was 'constructed' by Stefanick and McKee before leg 2 began. 
This instrument contains the transducers and pressure housing of WHM15O 
#16283 and the circuit boards of WHM15O #19394 (it was found on leg 1 that 
#16283 had functioning beams but yielded biased data; #19394 on the other 
hand yielded good data but had a failed beam -- since this hybrid instrument 
uses the electronics of #19394, we refer to it by that serial number). The 
other two instruments used are model WHM300.

Initial configuration consisted of the WHM15O #19394 as downlooker and the 
WHM300 #13330 as uplooker. Command files for both instruments used 16 m bins, 
32 m pulse length, and 0 m blanking. These choices were made to exploit 
maximal range in a region of low scattering. Staggered pinging was used to 
avoid previous ping interference. This instrument configuration was used for 
stations 113-117. To acquire a benchmark of comparison for the new #19394 
downlooker and command files, the downlooker was switched out for WHM300 
#12243 and that instrument was used for stations 118-133. The quality of 
profile as assessed by the root mean square (rms) difference between the 
SADCP data and the LADCP data unconstrained by SADCP data (figure 01) 
suggested that data collected with the WHM150 downlooker were of better 
quality. Therefore WHM150 #19394 was reinstalled before station 134.

During the full-depth cast on station 138 following a cast for the cesium 
group, the two instruments recorded multiple files, indicating a likely 
battery failure. Though the battery was charged between casts, Stefanick 
suggested that the short interval between them (about 15 minutes) was 
insufficient to fully charge the battery. Voltage was measured before the 
following casts and was adequate (~51 V), although on station 141 multiple 
files were again recorded. CTD problems at station 142 afforded an additional 
2.5 hours of trickle charge. This seemed to completely recharge the battery, 
and complete profiles were recorded through station 145. At station 146, 
arcing occurred while checking voltage and so the battery pack was swapped 
out.

Configuration was not changed until station 172, where the uplooker was 
replaced with the other WHM300, #12243. It was noticed that two beams on 
#13330 were performing at or below 90% while all four beams on #12243 were 
known to perform near 100%. Though beam performance was not nearly weak 
enough to prompt a warning from the software, the UVP was off the rosette for 
maintenance making this switch convenient.

By station 173 it became apparent that data in the far bins (>9) of the 
downlooker ensemble profiles were contaminated, as indicated by coherent 
structure in the velocity bias. While the bias is large, Thurnhen was not 
severely concerned about overall profile quality since the LADCP-SADCP rms 
error has been good. McKee re-processed the data while excluding these 
contaminated bins. This improved the LADCP-SADCP rms agreement (figure 02), 
suggesting that while the bias is affecting profile quality, good profiles 
are likely retrievable. A problematic profile is shown in figure 03 and shown 
re-processed in figure 04. WHM150 #19394 recorded data with similar 
contamination during leg 1 and it was hypothesized that the bias was 
exaggerated on leg 2 due to the longer pulses used (32 m). To test this, on 
station 178 the downlooker #19394 was programmed with the command file used 
on leg 1, station 90, though the condition did not improve. Therefore 
original command files were used again beginning at station 179. It was 
preferred to keep the current instrument configuration and restrict bins in 
processing since the WHM300 as downlooker - the only other option - tends to 
yield only about <9 bins of quality data anyway.


LADCP Operation

ADCP programming and data acquisition were carried out using the LDEO Acquire 
software running on a Mac computer. Communications between the acquisitions 
computer and the ADCPs took place across two parallel R5232 connections via a 
Keyspan USA-49WG 4-port USB-to-R5232 adapter. There were no significant 
communications issues throughout the entire cruise. After sending the 
corresponding command files to the instruments prior to each cast, 
communication between the computer and the instrument was terminated, the 
battery charger was turned off, the deck cables were disconnected, and all 
connections were sealed with dummy plugs and secured. Silicone spray was 
applied to all plugs once daily. After the CTD was brought back on deck 
following a cast, the data and the power supply cable were rinsed with fresh 
water and reconnected to the computer and battery charger via the deck 
cables. The battery charger was then powered on. Data acquisition was 
terminated and the data were downloaded using the Acquire software. The 
battery charger remained on from the time of data download until the time the 
instrument was prepared for the next cast. Log files were kept for each cast 
to ensure that all the steps were completed.


Data Processing and Quality Control

The LADCP data were processed by McKee at least once per day on a Windows 7 
laptop using the Matlab-based LDEO IX_10 processing software(1). This 
software principally uses the velocity inversion method, constrained by 
SADCP, GPS, and bottom-track data, to obtain a full-depth velocity profile. 
It also calculates a shear-based solution and compares the two, which, under 
ideal conditions, should agree. Each processed profile was inspected for 
realistic values and compared to the constraining data sources. Further, any 
warnings issued by the software were addressed. The processing figures 
produced by the software for each cast were inspected, which included 
checking the realism of final profile values, checking for any biased shear, 
examining the agreement between aligned CTD/LADCP time series, and monitoring 
beam strength and range. Thurnhen was either sent data or consulted when 
questionable profiles were observed.

In addition to the output from the processing software, a log was kept of the 
rms difference between the SADCP profiles and the LADCP profiles 
unconstrained by SADCP data during processing. This is one measure of profile 
quality. As soon as far-bin-contaminated velocity values were observed, a 
second log of rms difference was kept where far bins were ignored in 
processing.

Preliminary best processing omits bins > 9 for all profiles using WHM15O 
#19394 as downlooker. These re-processed profiles tend to have more realistic 
(i.e., smaller) abyssal values. Including [excluding] the contaminated bins 
in processing, about 25% [17%] of all samples deeper than 2000 m had velocity 
> 7 cm/s. For reference, in the 2006 occupation of PI 6N, about 16% of all 
samples deeper than 2000 m had velocity components that large. By figure 02, 
these re-processed data are indeed of better quality, at least in the upper 
ocean. Preliminary data are shown as gridded sections in figure 05.

Post-cruise processing is necessary and will be conducted at LDEO. At that 
point it will be determined which profiles are of sufficient quality for 
inclusion in the final CLIVAR ADCP archives.


















(1) http ://www.ldeo.columbia.edu/cgi-binlladcp-cgi-binlhgwebdir.cgi/LDEO_IXI



Photo 01:  Instruments and battery pack on rosette. UVP is not mounted in 
           this photo.

Figure 01: Root-mean-square difference between SADCP velocities and LADCP 
           velocities that were unconstrained by the SADCP data in the 
           inversion.

Figure 02: As in figure 01, except only near-bins were used in processing.

Figure 03: Inversion residuals (left - time/depth space; middle - bin-
           averaged) and velocity time series (right) for a profile with far-
           bin velocity bias. The left panels should be approximately random 
           but instead indicate structure (bias) in the far bins.

Figure 04: As in figure 03, but with far bins ignored in processing.

Figure 05: Smoothed sections gridded with a Gaussian weighting function. 
           Color bar is saturated. Wedges indicate profile locations and 
           solid black line indicates 0 m/s contour.











2015 CLIVAR P16N leg 2 SADCP Cruise Report

Eric Firing (UH; PI) and Jules Hummon (UH, PI)




Sampling

The Ronald H. Brown has a permanently mounted 75 kHz acoustic Doppler current 
profiler (Teledyne RDI) for measuring ocean velocity in the upper water 
column. The ADCP is a Phased Array instrument, capable of pinging in 
broadband mode (for higher resolution), narrowband mode (lower resolution, 
deeper penetration), or interleaved mode (alternating). On this cruise, data 
were collected with 8 m broadband pings and 16 m narrowband pings. The depth 
range achieved depends on weather (bubbles), installation (eg. ship noise), 
scattering levels, and other factors. Data were recorded during the entire 
cruise.


Processing

Specialized software developed at the University of Hawaii has been installed 
on the Brown for the purpose of ADCP acquisition, preliminary processing, and 
figure generation during each cruise. The acquisition system ("UHDAS", 
University of Hawaii Data Acquisition System) acquires data from the ADCPs, 
gyro heading (for reliability), Mahrs and POSMV headings (for increased 
accuracy), and GPS positions from various sensors. Single-ping ADCP data are 
automatically edited and combined with ancillary feeds, averaged, and 
disseminated via the ship's web, as regularly-updated figures on a web page 
and as Matlab and netCDF files.


Data Quality

The ADCP on board the Ron Brown died during 2014. NOAA worked hard to get 
another 75kHz instrument installed prior to this field season. We are 
grateful for their effort, as the ADCP has been functioning well since its 
installation early in 2015. Attempts were also made to improve the degrading 
POSMV, but those efforts did not lead to improvement. In fact the POSMY was 
useless early in the season (100% data loss), but has regained some quality 
and now functions about 60%-70% of the time. This means we will continue to 
have to depend on the Mahrs, which is not as accurate an instrument, when the 
POSMY is not healthy.


Summary

Shipboard ADCP data were collected for the duration of P16N, Leg 2. Data 
range is typical, 600m-700m in general. The ADCP system and data were 
monitored remotely. There were no changes or errors noted, beyond the 
persistent poor performace of the POSMV. Although the Mahrs and the POSMV are 
supposed to be accurate, neither is perfect and post-processing of the ADCP 
data will be necessary to obtain best accuracy for data while the ship is 
steaming. When the ship speed is near zero, heading errors do not cause 
significant errors in ocean velocity. Therefore the automated at-sea product 
should be good enough for preliminary use while the ship is on station. With 
the exception of the POSMV, the instrument, ancillary devices, and 
acquisition system performed well.









UNDERWATER VISION PROFILER (UVP) Report

Jessica Turner (Participant)
Andrew McDonnell (PI)




System configuration and sampling
       
The Underwater Vision Profiler 5 (UVP5) serial number 009 was mounted on the 
rosette, programmed, charged, and operated using the exact same procedures as 
in Leg 1 of the cruise. This optical imaging device obtains in situ 
concentrations and images of marine particles and plankton throughout the 
water column, capturing objects sized 0.64 gm to several cm in equivalent 
spherical diameter. The instrument and data processing are described in 
Picheral et al. (2010).


Figure XX. Transect of total particle concentration (number of particles per 
           liter) determined by the UVP5 along the 152° W line.

Figure XX. Transect of total particle concentration (number of particles per 
           liter) determined by the UVP5 at the Kodiak shelf stations 179-
           187.

Figure XX. Transect of total particle concentration (number of particles per 
           liter) determined by the UVP5 along the cross-gyre stations 193-
           207.


Problems

On a few occasions (stations 125,128,135,138,144,147,153) the UVP failed to 
collect data. The most likely cause was determined to be insufficient 
charging, or possibly unplugging the power cables before the charging unit 
had been turned off.

Overall, the performance of the lithium ion battery inside the UVP decreased 
over the course of Leg 2, with the maximum voltage of the instrument 
decreasing from 28.5 to 27.4. This caused the UVP to shut off partway through 
its descent through the water column, so the instrument did not collect full 
depth casts for many of the Leg 2 stations on the 152°W line. Depths of casts 
varied between 1500 m and 4000 m.


Battery recharge operations

The first attempt to fix the UVP battery occurred on June 13-14 (skipping UVP 
data collection for stations 168-171), using a 53W lightbulb to drain the 
battery and recharge it. The battery could only be drained to a minimum of 
22.0 V, however, so the decision was made to recharge it in order to collect 
data on more casts, albeit shallow profiles. Total discharge time and 
recharge time took 22 hours and 3 hours, respectively.
       
During the steam from the end of the 152°W line to the beginning of the 
cross-gyre line (between stations 189 and 191), the second attempt to fix the 
UVP battery was carried out using computer fans instead of a lightbulb. This 
was much more successful, draining the battery almost completely before 
recharging it to a much higher maximum voltage of 28.7 V. Total discharge 
time and recharge time took 20 hours and 4 hours, respectively.


Reference:

Ficherai, M., Guidi, L., Stemmann, L., Karl, D.M., Iddaoud, G., Gorsky, G., 
    2010. The Underwater Vision Profiler 5: An advanced instrument for high 
    spatial resolution studies of particle size spectra and zooplankton. 
    Limnol. Ocean. Methods 8,462-473.














BONGO NET DEPLOYMENT REPORT

Jessica Turner: participant
Nina Bednarsek - PI




Deployment

The bongo net was connected to the forward winch wire, with the flowmeter and 
a 60-lb weight suspended from the frame between the two nets. The net was 
deployed every night of sampling except for two nights, for a total of 26 
casts (+ test cast). On those two nights, the main CTD rosette wire (aft 
wire) was being lubricated, so the rosette was deployed off the forward wire 
in place of the bongo net. The timing of the cast varied depending on arrival 
times at stations, but always fell well between the local time of sunrise and 
sunset. Deployment always occurred at an official P16N station, with timing 
occurring either before the CTD cast, after the CTD cast, or between the 1000 
m cast and the following full cast at the same station.

After connecting the cod ends to the respective ends of the 200 and 300µm 
mesh size nets, the bongo was lifted so that the weight could pass just above 
the safety line, and the cod ends were lifted over the side before the net 
was boomed out and lowered to the water. The time the net entered the water 
was noted by the CTD watchstander on paper and as an event in the ship's log. 
The net was then lowered to 140 meters of wire out, at a target wire angle of 
450, for a target depth of 100 meters. Wire angle was measured with a simple 
plum-line style inclinometer. Often the wire angle varied throughout the cast 
between 300 and 550, and the variations were recorded along with how many 
meters of wire were out when they occurred. Flowmeter readings were recorded 
before and after each bongo cast by the CTD watch stander.

When recovering the net, the time it emerged from the water was recorded by 
the CTD watch stander and in the ship's event log. The net was held with the 
frame 3 ft above the main deck for a saltwater rinse, then brought onboard by 
carefully lifting the cod ends over the safety lines as it was boomed in. 
Once on deck, the lower ends of the net and the outside of the cod ends were 
rinsed thoroughly with saltwater before the cod ends were detached and 
brought inside for sample preservation.


Sample Preservation

The samples from each mesh size net were preserved separately. For each cod 
end, the plankton was poured into a plankton sock, using the seawater squirt 
bottle to rinse all plankton out of the cod end. While the sample was in the 
plankton sock, any large (>4 cm) fish or gelatinous organisms were removed 
from the sample. The plankton sock was then inverted into a jar (or several 
jars) and rinsed with the ethanol squirt bottle. Ethanol was then dispensed 
into the jar(s) in an approximate volume ratio of ~3:1 ethanol:plankton. The 
number of jars collected from a given station varied from 2-8 (1-4 jars from 
each cod end). The 200µm samples were frozen in an extra chest freezer, while 
the 300µm samples were stored at room temperature in the wet lab where they 
were preserved. 12-24 hours after original sample preservation, samples from 
each jar were poured into the plankton sock, inverted back into the jars, and 
fresh ethanol was dispensed for long-term storage.






APPENDIX

Bottle Data Quality Code Summary and Comments

This section contains WOCE quality codes [Joyc94] used during this cruise, 
and remarks regarding bottle data.


P16N Water Sample Quality Code Summary

    Property            1    2     3    4   5    6    7  8  9  Total
    ----------------  ----  ----  ---  ---  --  ----  -  -  -  -----
    Bottle               0  5358   24    9   0     0  0  0  9  5400
    CFC-11               0  3206   13   32  37     0  0  0  0  3288
    CFC-12               0  3226   12   13  37     0  0  0  0  3288
    N2O                  0  3240    1   10  37     0  0  0  0  3288
    SF6                  0  3184   25   42  37     0  0  0  0  3288
    3 He               471     0    0    1   5     0  0  0  0   477
    Neon               471     0    0    1   5     0  0  0  0   477
    Dissolved O2         0  4750   42   39   6     2  0  0  0  4839
    DIC                  0  3743   28   48   0   536  0  0  0  4355
    pH                   0  3171   44    7   3  1133  0  0  0  4358
    pH_usf               0     0    0    0   0    95  0  0  0    95
    Total Alkalinity     0  3949   21    5   3   380  0  0  0  4358
    13C                976     0    0    0   0     0  0  0  0   976
    14C                976     0    0    0   0     0  0  0  0   976
    DOC               2633     0    0    1   0     0  0  0  0  2634
    TDN               2633     0    0    1   0     0  0  0  0  2634
    DO 14C             105     0    0    0   0     0  0  0  0   105
    DO 14C (Unfilt.)     2     0    0    0   0     0  0  0  0     2
    POC                 54     0    0    0   0     0  0  0  0    54
    Chlorophyll a        0   383    3    2  12     0  0  0  0   400
    Tritium            457     0    0    1   0     0  0  0  0   458
    Nitrate              0  4030    0    7  11   801  0  0  1  4850
    Nitrite              0  4026    0    7  11   805  0  0  1  4850
    Phosphate            0  3804    0  267  12   766  0  0  1  4850
    Silicic Acid         0  4035    0    7  11   796  0  0  1  4850
    Salinity             0  4359  107   13   3   367  0  0  0  4849
    134Cs              719     0    0    0   0     0  0  0  0   719
    137Cs              719     0    0    0   0     0  0  0  0   719
    1291               719     0    0    0   0     0  0  0  0   719
    90Cs               719     0    0    0   0     0  0  0  0   719
    Black Carbon        53     0    0    0   0     0  0  0  0    53
     
   
Quality evaluation of data included comparison of bottle salinity and bottle 
oxygen data with CTDO data using plots of differences; and review of various 
property plots and vertical sections of the station profiles and adjoining 
stations. Comments from the Sample Logs and the results of investigations 
into bottle problems and anomalous sample values are included in this report. 
Sample number in this table is the cast number times 100 plus the bottle 
position number.










P16N Bottle Quality Codes and Comments

Station  Sample            Quality
/Cast    Number  Property  Code     Comment
-------  ------  --------  -------  -----------------------------------------
113/2    218     O2           4     Does not fit cast profile, adjacent casts 
                                    or other criteria. Analytical or sample 
                                    problems likely.
114/1    121     Bottle       3     Nisk.21 leaking from bottom end cap.
115/2    209     DIC          4     Probable instrument malfunction
115/2    211     DIC          4     Probable instrument malfunction
115/2    212     DIC          4     Probable instrument malfunction
115/2    213     DIC          4     Probable instrument malfunction
115/2    214     DIC          4     Probable instrument malfunction
115/2    215     DIC          4     Probable instrument malfunction
115/2    216     DIC          4     Probable instrument malfunction
115/2    217     Bottle       4     Mis-trip. Parameter values support mis-
                                    trip on bottle 17.
115/2    217     DIC          4     Probable instrument malfunction
115/2    217     Nitrite      4     Mis-trip
115/2    217     Nitrate      4     Mis-trip
115/2    217     O2           4     Mis-trip
115/2    217     pH           4     Mis-tripped Niskin bottle
115/2    217     Phosphate    4     Mis-trip
115/2    217     Salinity     4     Mis-trip
115/2    217     Silicate     4     Mis-trip
115/2    218     DIC          4     Probable instrument malfunction
115/2    219     DIC          4     Probable instrument malfunction
115/2    220     DIC          4     Probable instrument malfunction
115/2    221     DIC          4     Probable instrument malfunction
115/2    222     DIC          4     Probable instrument malfunction
115/2    224     DIC          4     Probable instrument malfunction
116/1    101     O2           4     Does not fit cast profile, adjacent casts 
                                    or other criteria. Analytical or sampling 
                                    problems are likely.
116/1    121     Bottle       3     Nisk.21 leaking from bottom end cap.
116/1    122     O2           4     Does not fit cast profile, adjacent casts 
                                    or other criteria. Analytical or sampling 
                                    problems are likely.
116/1    123     O2           4     Does not fit cast profile, adjacent casts 
                                    or other criteria. Analytical or sampling 
                                    problems are likely.
117/1    101     DIC          4     Probable instrument malfunction
117/1    101     pH           3     High baseline absorbance (Ao) due to 
                                    bubble in cell.
117/1    103     O2           4     Does not fit cast profile, adjacent casts 
                                    or other criteria. Analytical or sampling 
                                    problems are likely.
117/1    109     DIC          4     Probable instrument malfunction
117/1    111     DIC          4     Probable instrument malfunction
117/1    112     DIC          4     Probable instrument malfunction
117/1    113     DIC          4     Probable instrument malfunction
117/1    114     DIC          4     Probable instrument malfunction
117/1    115     DIC          4     Probable instrument malfunction
117/1    116     DIC          4     Probable instrument malfunction
117/1    117     DIC          4     Probable instrument malfunction
117/1    118     DIC          4     Probable instrument malfunction
117/1    119     DIC          4     Probable instrument malfunction
117/1    120     DIC          4     Probable instrument malfunction
117/1    121     DIC          4     Probable instrument malfunction
117/1    122     DIC          4     Probable instrument malfunction
117/1    124     DIC          4     Probable instrument malfunction
118/3    319     Salinity     3     Does not fit cast profile. No ananlytical 
                                    problems noted. High gradient. Code 
                                    questionable.
118/3    324     O2           3     Does not fit cast profile, adjacent casts 
                                    or other criteria. High for adjacent 
                                    surface casts. No analytical problems 
                                    noted.
119/1    101     DIC          4     Probable instrument malfunction
119/1    104     DIC          4     Probable instrument malfunction
119/1    107     DIC          4     Probable instrument malfunction
119/1    110     DIC          4     Probable instrument malfunction
119/1    113     DIC          4     Probable instrument malfunction
119/1    114     DIC          4     Probable instrument malfunction
119/1    124     DIC          3     Probable instrument malfunction
120/2    219     O2           3     Does not fit cast profile, adjacent casts 
                                    or other criteria. No problems were noted 
                                    by the analyst.
121/2    219     Salinity     3     Does not fit cast profile. No problems 
                                    were noted by the analyst. High gradient. 
                                    Code questionable.
122/1    109     TAlk         5     Instrument malfunction. Sample lost.
122/1    120     Bottle       3     Sample bottle lanyard caught on recovery 
                                    and water lost on deck.Niskin leaking.
123/2    206     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
123/2    207     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
124/1    106     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
124/1    106     TAlk         3     Possibly low? Value confirmed with a 
                                    rerun.
124/1    108     Salinity     4     Does not fit cast profile. Sampling or 
                                    analytical problems likely. Code bad.
125/1    109     Salinity     3     Does not fit cast profile. No problems 
                                    were noted by the analyst. Code 
                                    questionable.
125/1    122     Salinity     3     Does not fit cast profile. No problems 
                                    were noted by the analyst. Code 
                                    questionable.
126/1    101     Bottle       4     SLOG: "Temp on 1 high compared to others 
                                    nearby." CMS: Parameter measurements 
                                    indicate bottle may did not tripped at 
                                    intended depth.
126/1    101     Nitrite      4     Mis-trip
126/1    101     Nitrate      4     Mis-trip
126/1    101     O2           4     Mis-trip
126/1    101     pH           4     Mis-tripped Niskin bottle
126/1    101     Phosphate    4     Mis-trip
126/1    101     Salinity     4     Mis-trip
126/1    101     Silicate     4     Mis-trip
126/1    101     TAlk         3     Value looks really low. Niskin mis-trip 
                                    suspected. Value confirmed with a rerun.
126/1    119     Bottle       2     SLOG: Niskin is hard to close and results 
                                    in water loss from niskin.
127/1    101     Bottle       4     SLOG: "Bottle 1 high temp again." CMS: 
                                    Parameter measurements indicate bottle 
                                    may did not tripped at intended depth.
127/1    101     Nitrite      4     Mis-trip
127/1    101     Nitrate      4     Mis-trip
127/1    101     O2           4     Mis-trip
127/1    101     pH           4     Mis-tripped Niskin bottle
127/1    101     Phosphate    4     Mis-trip
127/1    101     Salinity     4     Mis-trip
127/1    101     Silicate     4     Mis-trip
127/1    101     TAlk         4     Niskin mis-trip suspected.
127/1    106     Salinity     3     Does not fit cast profile. Possibly mis-
                                    sampled. Sample value 6 compares well 
                                    sample S and CTD trip value at 5. Code 
                                    bad.
128/4    405     O2           4     Does not fit cast profile, adjacent casts 
                                    or other criteria. Sample or analytical 
                                    problems likely.
128/4    407     TAlk         3     Pretty sure this was filled with Niskin 8 
                                    water.
128/4    414     Bottle       2     SLOG: Niskin 14 dripping after sampling.
128/4    422     Salinity     3     Does not fit down cast profile. No 
                                    problems were noted by the analyst. Code 
                                    questionable.
129/1    119     TAlk         3     Possibly high
130/1    104     Bottle       2     SLOG: Niskin fired on the fly.
131/2    206     Salinity     3     Does not fit cast profile. No problems 
                                    were noted by the analyst. Code 
                                    questionable.
132/1    122     Refc.Temp.   4     SBE35 value reads high vs CTDT1 & CTDT2.
                                    8 sec delay likely not observed after 
                                    bottle trip. Code bad.
133/2    203     Salinity     4     Samples may have been run out of order. 
                                    After correcting sample 3 does not  match 
                                    profile. Code bad.
134/2    201     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
134/2    223     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
135/1    119     O2           3     Does not fit cast profile, adjacent casts 
                                    or other criteria.
135/1    122     O2           3     Does not fit cast profile, adjacent casts 
                                    or other criteria.
135/1    123     Refc.Temp.   2     Unstable temperature read in all three 
                                    sensors. High gradient. Code 
                                    questionable.
136/2    204     Salinity     4     Analytical samples show slight offset 
                                    with profile. Debris noted in autosal 
                                    cell. Code bad.
136/2    205     Salinity     4     Analytical samples show slight offset 
                                    with profile. Debris noted in autosal 
                                    cell. Code bad.
136/2    206     Salinity     4     Analytical samples show slight offset 
                                    with profile. Debris noted in autosal 
                                    cell. Code bad.
136/2    207     Salinity     4     Analytical samples show slight offset 
                                    with profile. Debris noted in autosal 
                                    cell. Code bad.
136/2    208     Salinity     4     Analytical samples show slight offset 
                                    with profile. Debris noted in autosal 
                                    cell. Code bad.
136/2    209     Salinity     4     Analytical samples show slight offset 
                                    with profile. Debris noted in autosal 
                                    cell. Code bad.
137/1    108     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
138/4    401     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code queastionable.
139/3    306     TAlk         3     Low
139/3    316     TAlk         5     Instrument malfunction.
142/3    303     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
143/2    209     Salinity     4     Does not fit cast profil. Possibly mis-
                                    sampled. Sample value compares better 
                                    with niskin 8. Code bad.
143/2    224     TAlk         3     Possibly high
144/1    111     Salinity     4     Does not fit cast profile, adjacent casts 
                                    or other criteria. Sampling or analytical 
                                    problems likely. Code bad.
146/2    204     TAlk         3     High
146/2    205     TAlk         3     High
146/2    218     chlor        5     KB: Sampling contamination issue. Samples 
                                    not recorded.
146/2    219     chlor        5     KB: Sampling contamination issue. Samples 
                                    not recorded.
146/2    220     chlor        5     KB: Sampling contamination issue. Samples 
                                    not recorded.
146/2    221     chlor        5     KB: Sampling contamination issue. Samples 
                                    not recorded.
146/2    222     chlor        5     KB: Sampling contamination issue. Samples 
                                    not recorded.
146/2    223     chlor        5     KB: Sampling contamination issue. Samples 
                                    not recorded.
146/2    224     chlor        5     KB: Sampling contamination issue. Samples 
                                    not recorded.
147/1    109     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
149/1    101     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
149/1    103     Nitrite      5     Niskins emptied before nutrients could be 
                                    samples.
149/1    103     Nitrate      5     Niskins emptied before nutrients could be 
                                    samples.
149/1    103     Phosphate    5     Niskins emptied before nutrients could be 
                                    samples.
149/1    103     Silicate     5     Niskins emptied before nutrients could be 
                                    samples.
149/1    104     Nitrite      5     Niskins emptied before nutirents could be 
                                    samples.
149/1    104     Nitrate      5     Niskins emptied before nutrients could be 
                                    samples.
149/1    104     Phosphate    5     Niskins emptied before nutrients could be 
                                    samples.
149/1    104     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
149/1    104     Silicate     5     Niskins emptied before nutrients could be 
                                    samples.
149/1    106     Salinity     4     Does not fit cast profile. Sampling or 
                                    analytical problems likely. Code bad.
150/3    304     pH           3     Difference between replicate measurements 
                                    was 0.0014 units.
151/2    201     Bottle       2     SLOG: Bottle fired at same depth.
151/2    202     Bottle       2     SLOG: Bottle fired at same depth.
152/1    101     O2           4     Does not fit cast profile, adjacent casts 
                                    or other criteria. Analytical or sampling 
                                    problems are likely.
152/1    107     Salinity     4     Does not fit cast profile. Sampling or 
                                    analytical problems likely. Code bad.
152/1    120     Salinity     3     Does not fit cast profile. Edge of high 
                                    gradient. Code questionable.
153/2    209     Salinity     4     Does not fit cast profile. Sampling or 
                                    analytical problems likely. Code bad.
154/2    203     Salinity     3     Does not fit cast profile. Sample value 
                                    compares better with niskin 2. Possibly 
                                    mis-sampled. Code questionable.
154/2    205     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
154/2    206     Salinity     3     Does not fit cast profile. Sampling or 
                                    analytical problems likely. Code bad.
154/2    214     O2           4     Does not fit cast profile, adjacent casts 
                                    or other criteria. Analytical or sampling 
                                    problems are likely.
154/2    214     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
155/1    102     Salinity     4     Does not fit cast profile. Possibly mis-
                                    sampled. Sample value compares better 
                                    with niskin 1. Code bad.
156/2    203     O2           4     Does not fit cast profile, adjacent casts 
                                    or other criteria. Analytical or sampling 
                                    problems are likely.
156/2    206     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
156/2    208     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
157/1    102     Salinity     4     Does not fit cast profile. Sampling or 
                                    analytical problems likely. Code bad.
157/1    106     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
157/1    107     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
157/1    118     Salinity     3     Does not fit down cast profile. Edge of 
                                    high gradient. Code questionable.
157/1    120     Salinity     3     Does not fit cast profile. High gradient. 
                                    Code questionable.
157/1    124     pH           3     Difference between replicate measurements 
                                    was 0.0033 units
158/3    305     Bottle       2     SLOG: Niskin fired on the fly.
158/3    305     pH           3     Difference between replicate measurements 
                                    was 0.0024 units
158/3    307     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
158/3    308     Salinity     4     Does not fit cast profile. Sampling or 
                                    analytical problems likely. Code bad.
158/3    321     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Edge of high gradient. 
                                    Code questionable.
158/3    322     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Edge of high gradient. 
                                    Code questionable.
159/1    103     Salinity     4     Does not fit cast profile. Possibly mis-
                                    sampled. Sample value compares better 
                                    with niskin 2. Code bad.
159/1    109     Salinity     4     Does not fit cast profile. Sampling or 
                                    analytical problems likely. Code bad.
159/1    115     O2           4     Sample value does not fit cast profile, 
                                    adjacent casts or other criteria. 
                                    Analytical or sampling problems are 
                                    likely.
159/1    122     Refc.Temp.   2     SBE35 value high vs. CTDT1 & CTDT2. 8 
                                    second trip delay likely not observed. 
                                    Code bad.
159/1    123     O2           4     Sample value does not fit cast profile, 
                                    adjacent casts or other criteria. Likely 
                                    fits up cast data. Code questionable.
160/1    105     Salinity     4     Does not fit cast profile. Debris noted 
                                    in analytical cell.
160/1    106     Salinity     4     Does not fit cast profile. Debris noted 
                                    in analytical cell.
160/1    107     Salinity     4     Does not fit cast profile. Debris noted 
                                    in analytical cell.
160/1    114     Salinity     4     Does not fit cast profile. Debris noted 
                                    in analytical cell.
160/1    120     Refc.Temp.   3     SBE35 value high vs. CTDT1 & CTDT2. Code 
                                    questionable
160/1    122     Refc.Temp.   3     SBE35 value high vs. CTDT1 & CTDT2. Code 
                                    questionable
161/2    211     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
162/3    301     Salinity     3     Does not fit cast profile. Samples 
                                    possibly run before reaching lab 
                                    temperature equilibrium. Code 
                                    questionable.
162/3    302     Salinity     3     Does not fit cast profile. Samples 
                                    possibly run before reaching lab 
                                    temperature equilibrium. Code 
                                    questionable.
162/3    303     Salinity     3     Does not fit cast profile. Samples 
                                    possibly run before reaching lab 
                                    temperature equilibrium. Code 
                                    questionable.
162/3    305     Salinity     3     Does not fit cast profile. Samples 
                                    possibly run before reaching lab 
                                    temperature equilibrium. Code 
                                    questionable.
162/3    308     Salinity     4     Does not fit cast profile. Sampling or 
                                    analytical problems likely. Code bad.
163/2    202     Salinity     4     Does not fit cast profile. Possibly mis-
                                    sampled. Sample value compares better 
                                    with niskin 2. Code bad.
163/2    206     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable. 
163/2    207     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
164/2    223     pH           3     Difference between duplicates was 0.0017.
164/2    223     Refc.Temp.   4     Unstable temperature read in all three 
                                    sensors. High gradient. Code bad.
166/3    306     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
166/3    310     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
166/3    320     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
167/1    103     pH           3     Difference between replicate measurements 
                                    was 0.0015 units
167/1    109     Salinity     4     Does not fit cast profile. Analytical or 
                                    sampling problems are likely. Code bad.
167/1    120     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
167/1    123     Salinity     4     Does not fit cast profile. Analytical or 
                                    sampling problems are likely. Code bad.
168/1    103     Salinity     4     Does not fit cast profile. Possibly mis-
                                    sampled. Sample value compares better 
                                    with niskin 2. Code bad.
168/1    103     TAlk         3     Seems high. Value confirmed with 
                                    Duplicate.
168/1    105     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
168/1    106     Salinity     5     Sample missing. Possibly skipped niskin 
                                    while sampling.
169/2    204     O2           4     Does not fit cast profile, adjacent casts 
                                    or other criteria. Analytical or sampling
                                    problems are likely.
170/2    208     Salinity     3     Does not fit cast profile. No analytical 
                                    problems are likely. Code questionable.
170/2    220     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
170/2    223     Refc.Temp.   3     SBE35 value reads low vs CTDT2 & SBE35. 
                                    Code questionable.
171/1    102     Salinity     2     Does not fit cast profile, adjacent casts 
                                    or other criteria. Possibly sampled from 
                                    the wrong niskin. Value compares well 
                                    with bottle 101 sample. Left for PI 
                                    review.
171/1    121     Salinity     4     Does not fit cast profile, adjacent casts 
                                    or other criteria. Presumably fresher 
                                    water at surface is causing analytical 
                                    problems in the high gradient region of 
                                    profile. Code bad.
172/1    101     Salinity     4     Does not fit cast profile, adjacent casts 
                                    or other criteria. Possibly sampled from 
                                    the wrong niskin. Code bad.
172/1    105     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
172/1    106     pH           3     Difference between replicate measurements 
                                    was 0.002 units
172/1    106     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
172/1    120     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
173/1    101     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
173/1    106     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
173/1    120     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
174/3    306     Salinity     4     Does not fit cast profile. Possibly mis-
                                    sampled. Sample compares better with 
                                    sample drawn from btl 5. Code bad.
174/3    307     Salinity     4     Does not fit cast profile. Sampling or 
                                    analytical problems likely. Code bad.
174/3    324     pH           3     Difference between duplicates was 0.0025.
175/1    102     Salinity     4     Does not fit cast profile. Possibly 
                                    sampled from the wrong niskin. Value 
                                    compares well with bottle 101 sample. 
                                    Code bad.
175/1    121     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
175/1    122     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
175/1    123     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
176/2    202     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    203     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    204     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    205     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    206     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    207     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    208     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    209     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    210     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    211     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    211     O2           4     Does not fit cast profile, adjacent casts 
                                    or other criteria. Analytical or sampling 
                                    problems are likely.
176/2    212     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    213     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    214     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    215     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    216     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    217     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    218     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    219     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    220     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    221     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    222     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    223     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
176/2    224     ctdcl        4     CTDCl had a notable scaling offset during 
                                    upcast. Biofouling observed on primary 
                                    conductivity sensor.
177/1    101     Salinity     4     Does not fit cast profile. Analytical or 
                                    sampling problems are likely. Code bad.
177/1    105     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
177/1    110     Salinity     4     Sample accidentally tripped on the fly. 
                                    Sample does not match CTDCl or the other 
                                    salinity sample at same depth. Code bad.
177/1    121     pH           3     Difference between replicate measurements 
                                    was 0.0028 units
177/1    121     Refc.Temp.   3     Unstable temperature read in all three 
                                    sensors. High gradient. Code 
                                    questionable.
177/1    123     Refc.Temp.   3     Unstable temperature read in all three 
                                    sensors. High gradient. Code 
                                    questionable.
178/3    319     Bottle       2     SLOG: Leak on bottle seal of niskin 19.
178/3    321     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
179/1    107     Salinity     3     Does not fit cast profile. Analytical or 
                                    sampling problems are likely. Code bad.
179/1    120     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the  high 
                                    gradient region of profile. Left for  PI 
                                    review.
179/1    121     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the  high 
                                    gradient region of profile. Left for PI 
                                    review.
180/2    201     Salinity     3     Does not fit cast profile. No problems 
                                    were noted by the analyst. Code 
                                    questionable.
180/2    210     Salinity     3     Does not fit cast profile. No problems 
                                    were noted by the analyst. Code 
                                    questionable.
180/2    222     pH           3     Difference between duplicates was 0.0011 
                                    units.
180/2    223     Refc.Temp.   3     Unstable temperature read in all three 
                                    sensors. High gradient. Code 
                                    questionable.
181/1    103     Salinity     3     Does not fit cast profile. No problems 
                                    were noted by the analyst. Code 
                                    questionable.
181/1    108     pH           3     Difference between replicate measurements 
                                    was 0.0033 units.
181/1    121     Salinity     4     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
181/1    122     Salinity     4     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
183/1    103     Salinity     3     Does not fit cast profile. No problems 
                                    were noted by the analyst. Code 
                                    questionable.
183/1    110     TAlk         3     Might be 4 units high.
183/1    114     TAlk         3     Might be 5 units high.
183/1    119     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
183/1    120     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
184/1    101     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
184/1    102     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
184/1    120     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
185/1    117     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
186/1    113     pH           2     Large plankton in sample.
186/1    114     pH           6     Large plankton in sample.
186/1    121     pH           2     Plankton and glassy shards observed in 
                                    sample.
187/3    316     Salinity     4     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Code bad.
187/3    318     Salinity     4     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Code bad.
189/1    110     Salinity     4     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Code bad.
190/1    115     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
191/4    402     Salinity     4     Does not fit cast profile. Sample 
                                    compares better with niskin 1. Possible 
                                    mis-sample. Code bad.
191/4    405     Salinity     3     Does not fit down cast profile. No 
                                    problems were noted by the analyst.
191/4    406     Salinity     3     Does not fit down cast profile. No 
                                    problems were noted by the analyst.
191/4    413     pH           3     Difference between replicate measurements 
                                    was 0.0013
192/1    103     Salinity     3     Does not fit cast profile, adjacent casts 
                                    or other criteria. No problems were noted 
                                    by the analyst.
192/1    122     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
193/1    103     pH           3     Difference between duplicates was 0.0019 
                                    units
193/1    117     pH           5     Bottle broke in lab.
193/1    122     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
193/1    123     Refc.Temp.   4     SBE3S value reads high vs CTDT1 & CTDT2. 
                                    Code bad.
194/1    101     Salinity     4     Does not fit cast profile. Possible 
                                    contamination from fresh water surface in 
                                    cell from analysis run prior to 194. Code 
                                    bad.
194/1    121     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
194/1    122     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
195/2    201     Salinity     3     Does not fit cast profile. No problems 
                                    were noted by the analyst.
195/2    202     Bottle       2     SLOG: Brown goop on niskin 2. DIC cleaned 
                                    it off.
195/2    208     Bottle       2     SLOG: Grey paint on niskin 8 spigot.
195/2    220     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
195/2    221     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
196/2    202     Salinity     4     Does not fit down cast profile. Possible 
                                    cross-contamination. Code bad.
196/2    210     Salinity     3     Does not fit down cast profile. No 
                                    problems noted by analyst. Code 
                                    questionable.
196/2    220     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
196/2    221     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
197/1    120     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
197/1    121     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
197/1    124     Refc.Temp.   4     Unstable temperature read in all three 
                                    sensors. High gradient. Code bad.
198/2    220     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
199/2    219     O2           4     Value matches bottle 218. Possibly 
                                    missampled.
200/1    118     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
200/1    119     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
200/1    120     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
201/2    202     Salinity     3     Does not fit cast profile. No analytical 
                                    problems noted. Code questionable.
201/2    219     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
201/2    220     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
201/2    221     Salinity     2     Does not fit down cast profile. 
                                    Presumably fresher water at surface is 
                                    causing analytical problems in the high 
                                    gradient region of profile. Left for PI 
                                    review.
203/2    201     TAII         3     Niskin mis-trip or leak suspected. Seems 
                                    high. Value confirmed with Duplicate.
203/2    219     pH           5     Bottle cracked in the water bath.
204/1    101     TAlk         3     Niskin mis-trip or leak suspected. Seems 
                                    high. Value confirmed with Rerun.
204/1    104     pH           3     Difference between duplicates was 0.0014 
                                    units
206/1    117     Refc.Temp.   4     SBE35 value reads high vs CTDT1 & CTDT2. 
                                    Wait time probably not observed. Code 
                                    bad.
206/1    118     Refc.Temp.   4     SBE35 value reads high vs CTDT1 & CTDT2. 
                                    Wait time probably not observed. Code 
                                    bad.
206/1    122     Salinity     4     Does not fit cast profile. Sampling or 
                                    analytical problems likely. Code bad.
206/1    124     pH           3     Difference between duplicates was 0.0022 
                                    units
207/1    114     Refc.Temp.   3     Unstable temperature read in all three 
                                    sensors. Code questionable.
207/1    115     Refc.Temp.   3     Unstable temperature read in all three 
                                    sensors. Code questionable.




References

Joyc94. Joyce, T., ed. and Cony, C., ed., "Requirements for WOCE Hydrographic 
    Programme Data Reporting," Report WHPO 90-1, WOCE Report No. 67/91., pp. 
    52-55, WOCE Hydrographic Programme Office, Woods Hole, MA, USA (May 1994, 
    Rev. 2).





CCHDO Data Processing Notes

Date       2015-07-22
Data Type  Flag updates
Action     Data available
Summary    salinity and oxygen flag updates
Name       Courtney Schatzman
Note       file p16n_hyl .csv submitted by Courtney Schatzman on 2015-07-21 
           available online as received
             notes:
                  salinity 126-1-1 yb vs ctdsal bad bottle mark 4
                  salinity 127-1-1 yb vs ctdsal bad bottle mark 4
                  oxygen 173-1-21 vvvlo vs ctdoxy,P mark 4 likely sample 
                      collection error

Date       2015-08-26
Data Type  Cruise Report
Action     Data available
Summary    Ready to go online
Name       Jerry Kappa
Note       The preliminary PDF cruise report for P16N_2015 Leg 2 is ready 
           to go online. It includes all of the PI-provided data reports, a 
           linked table of contents, linked figures and tables and these 
           CCHDO Data Processing Notes.



