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 UCSB/MSI Craig Carlson carlson@lifesci.ucsb.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.