preliminary data report
may 5, 1995

A.	Cruise Narrative

A.1.	Highlights

A.1.a	WOCE designation	AR18
 
A.1.b	EXPOCODE 		58JH1092/1 
				NORDIC WOCE PILOT CRUISE

A.1.c	Chief Scientist		Johan Blindheim, 
				Institute of Marine Research
				PO Box 1870 Nordnes
				Bergen, Norway
				N-5024
				e-mail: Johan@imr.no
				phone: +47-5-238500
				fax:   +47-5-238584

	Co-Chief Scientist	Erik Buch
				RDANH
				PO Box 1919
				Overgarden o. Vandet 62B
				Copenhagen, Denmark
				DK-1023
				e-mail:  Farvebu@unidhp.uni-c.dk
				phone:  +45-32-961288
				fax:    +45-31-574770


A.1.d	Ship			R/V Johan Hjort

A.1.e	Ports of Call		Departure from Bergen, Norway, with call in 
				Reykjavik, Iceland, and return to Bergen.

A.1.f	Cruise dates		12 - 28 July 1992.

A.2	Cruise summary

A.2.a	geographic boundaries

A.2.b	Total number of stations occupied

Sampling Accomplished

In total 32 CTD/rosette stations were occupied using a 12 bottle GO
rosette sampler with 10 l Niskin bottles. Samples for determination
of oxygen and nutrients (silicate, nitrate, nitrite and phosphate)
were drawn from all bottles. Samples for tracer analyses (CFC11,
CFC12, CFC113, CCl4, tritium/helium, C14, C13) as well as dissolved
inorganic CO2 and pCO2 were drawn from selected stations (See
AR18.SEA).

A.2.c	Total number of stations occcupied

A.2.d	Moorings deployed or recovered

A.3	Principal Investigators

Names of principal investigators for all variables measured are given
in the following table:

	Table 1:	List of Principal Investigators
-----------------------------------------------------------------------------
Name				Responsibility		Affiliation*
----------------------------------------------------------------------------
S. Osterhus		CTD/Rosette/Salinity		GI, Univ. Bergen
F. Rey			Oxygen, nutrients		IMR, Bergen
E. Fogelqvist		CFCs				Univ. Gothenburg
R. Bayer		Helium/tritium			Univ. Heidelberg
J. Olafsson		Carbon dioxide			MRI, Reykjavik
R. Nydal		Carb. isotopes/CO2		Univ. Trondheim
R. Hietala		ADCP				FIMR, Helsinki
----------------------------------------------------------------------------
* See table 3 for list of institutions

A.4	Scientific Programme and Methods

R/V Johan Hjort departed Bergen July 12, 1992 heading for the
northernmost station on section I. At each station a profile with a
Neil Brown Mark III CTD was performed, taking water samples using a
12 position GO rosette sampler with 10 l Niskin bottles. Sample
analysis included salinity, dissolved oxygen, nitrate, nitrite,
phosphate, silicic acid, CFC-tracers, carbon tetracloride, partial
pressure of carbon dioxide and dissolved inorganic carbon. Additional
samples were drawn and returned to shore laboratories for analysis of
tritium, helium, C14 and C13. Along-track measurements of upper layer
currents were performed using an Acoustic Doppler Current Profiler.

A.5	Major Problems and Goals not Achieved

The northern part of the Denmark Strait was covered with great
amounts of Arctic Ocean drift ice preventing us from reaching the
deeper parts just north of the Denmark Strait sill. For this reason
no sampling on the deep water masses could be carried out.

Some problems occurred due to unclear distribution of responsibility,
misunderstandings among  cruise participants belonging to different
research groups with little experience from earlier cooperation, and
simply, incomplete knowledge of WOCE operational procedures.  This
resulted in some deficiencies  in the data logging. Hense, meter
wheel readings were not logged although this variable was routinely
used on all stations. Similarly, salinity samples were not drawn from
all Niskin bottles.

The echo depth was recorded with the actual sound speed entered in
the echo sounder instead of 1500 m. On CTD stations real time print
out of sound speed was made every 5 decibar when the CTD was lowered
along with sound speed avereaged between the sea surface and the
current pressure.


A.7	List of Cruise Participants

	Table 2:	List of Cruise Participants
----------------------------------------------------------------------------
Participant			Responsibility		Affiliation*
----------------------------------------------------------------------------
Johan Blindheim		Chief Scientist			IMR, Bergen
Erik Buch		Co-chief scientist		RDANH, Copenhagen
Elisabeth Fogelqvist	CFCs				Univ. Gothenburg
Markus Frank		Helium/Tritium			Univ. Heidelberg
Jorunn Gislefoss	Carbon isotopes, CO2		Univ. Trondheim	
John Goddard		CO2				LDGO, Palisades
Rachel Goddard		CO2				LDGO, Palisades
Oystein Godoy		CTD/ADCP			GI, Univ. Bergen
Bogi Hansen		CTD/S				FLF, Torshavn
Stefan Kristmannsson	CTD/S				MRI, Reykjavik	
Mikael Krysell		CFCs				Univ. Gothenburg
Reidar Nydal		Carbon isotopes, CO2		Univ. Trondheim
Jon Olafsson		CO2				MRI, Reykjavik
Svein Osterhus		CTD, S			        GI, Univ. Bergen
Ronald Pedersen		Instrument techn.		IMR, Bergen
Francisco Rey		Nutrients, oxygen		IMR, Bergen
Paul Samuel		Remote sens. gr. truth		NERSC, Bergen
Jane Stromstad		Nutrients, oxygen		IMR, Bergen
Hannu Vouri		ADCP				FIMR, Helsinki
-----------------------------------------------------------------------
*See Table 3 for list of Institutions

	Table 3:	List of Institutions

Abbreviation		Institution
---------------------------------------------------------------------
MRI			Marine Research Institute
			Reykjavik, Iceland

IMR			Institute of Marine Research
			Bergen, Norway

RLD			Radiological Dating Laboratory
			Trondheim, Norway

FIMR			Finnish Institute of Marine Research
			Helsinki

LDGO(LDEO)		Lamont-Doherty Earth Observatory
			Palisades, New York, U.S.A

NERSC			Nansen Environmental Remote Sensing Center
			Bergen, Norway

FLF			Fisheries laboratory of the Faroes
			Thorshaven, Denmark
-------------------------------------------------------------------

Underway Measurements

B.1	Navigation and bathymetry
B.2	Acoustic Doppler Current Profiler (ADCP)
B.3	Thermosalinograph and underway dissolved oxygen, fluorometer, etc
B.4	XBT and XCTD
B.5	Meteorological observations
	

C.	Hydrographic Measurements		

C.1  	CTD Measurements

		By Svein Osterhus

Calibrations


The CTD measurements were carried out by means of an NBIS Mark III
CTD equipped with a General Oceanics Rosette sampler. This was a
system which was not upgraded to WOCE standards. Temperature and
conductivity were therefore read only to the third decimal place.
Calibrations in the laboratory was done in accordance with the
calibration instructions given by the manufacturer.

The CTD temparature sensor is manufactured by Rosemount who claim a
resolution of 0.0005 degrees C and an accuracy of 0.005 degrees C.
Prior to the cruise the CTD was checked at atmospheric pressure in
laboratory and the temperature was found to be correct within  0.001
degrees C both at 0 and +15 degrees C. The CTD was not checked in the
laboratory just after the cruise because the vessel went directly
over to an other project. When the next check in the laboratory was
made on 25 September, the CTD temperature was 0.001 degrees C too
high at 0 degrees C and 0.004 too high at 15 degrees C. No fast
response thermistor was used.

The CTD pressure sensor is manufactured by Paine instruments and
according to the supplier it has a resolution of 0.1 dbar and an
accuracy of 6 dbar.  Prior to the cruise it was found correct within
ist resolution at 0 dbar and at 3070 dbar.
 
The conductivity sensor is manufactured by NBIS who claim a
resolution of 0.001 mS and an accuracy of 0.005 mS. Calibrations were
made in laboratory prior to the cruise, but unfortunately, the
conductivity sensor was broken before it could be checked again after
the cruise.

Field calibrations were taken during upcast when Niskin bottles were
tripped and temperature, conductivity and pressure were read from the
display on the deck unit prior to and after tripping of the bottles.

During the cruise, a malfunctioning occurred on the temperature
display on the CTD deck unit which had the effect that the least
significant digit was fixed. This was not discovered before toward
the end of the cruise. In general this reduced the accuracy of
salinity field calibrations to the second decimal place.

CTD Data Collection and Processing.

CTD data aquisition was carried out by means of a HP Vectra PC, 386.
All data series were sampled and temporarily stored on hard disk.
Post processing was made in accordance with guidelines given  SCOR WG
51 (Flling Y. and J. Blindheim, 1991. Post processing of CTD data.
Report 4/1991/HSM. Institute of Marine Research, Bergen.) and
averages for each decibar were stored. Backup of CTD raw data was
transferred to digital casettes.

C.2 	Salinity Measurements

Twelve 10 litre Niskin bottles mounted on a General Oceanics Rosette
Sampler were used for water sampling. Unfortunately, samples for
determination of salinity were not collected from allsampling depths,
especially in the beginning of the cruise.

Salinities were analyzed onboard using a Guildline Portasal
salinometer which was checked daily against IAPSO standard Sea water
, Batch 120. Salinities were read directly from the salinometer to
the third decimal place. Salinometer bath temperature was set to 21
degrees C and room temperature was throughout the cruise kept between
19 and 21 degrees C. The salinity was determined at least twice on
all samples, and for 65 % of the samples the two readings agreed to
the third decimal place in salinity. Less than 1 % had differences
larger than 0.001 between the two first readings so that multiple
readings were necessary.

Duplicate or triplicate samples were drawn from the same Niskin
bottle in 21 cases. Difference between the samples was 0.000 or 0.001
in 19 cases, 0.002 in one case and 0.003 in one case.

C.3	Oxygen measurements

		By Francisco Rey

Oxygen concentration was measured using the Winkler method with
visual determination of the titration end-point. Titration was done
on  whole samples ( about 120 ml) using a 20 ml automatic burette (
Schotts-Gorens) with a dispensing precision of 0.01 ml. Calibration
of the thiosulfate (about 0.04 N ) was as a rule done twice a day.
The reproducibility of the method estimated as the standard deviation
of ten replicates drawn from one 10 l Niskin bottle is  0.015 ml / l
at an oxygen concentration of 6 ml / l. Reagents differed from WOCE
recommendations as follows: MnSO4 and HCl were used instead of MnCl
and H2SO4. Otherwise reagents preparation and analyses followed WOCE
recommendations as stated in Culberson (1991). Conversion of
volumetric to weight concentrations were done as recommended by WOCE
using potential temperature.


C.4 	Nutrient measurements
		
		By Francisco Rey
	
Equipment and Technique

The nutrient analyses were performed by a team from the Institute of
Marine Research, Bergen, Norway, using a system built up by the
following items: Pump system from ChemLab, England.  Reaction units
of own fabrication Autosampling , detection and computing units from
SANPLUS Segmented Flow Analyzer, Skalar  Analytical
B.V., The Netherlands.

The methods used were adaptations of standard methods (Strickland and
Parsons, 1972) slightly modified to the autoanalyzer system ( Fyn et
al., 1981). The precision for the different analyses at full scale
were less than 0.2% for nitrite, nitrate and silicic acid and less
than 2 % for phosphate. The reproducibility were less than 1% for
nitrite, nitrate and silicic acid and less than 3% for phosphate.

Sampling procedure

Seawater samples were collected just after the sampling for trace
gases and oxygen. After rinsing three times, samples were drawn into
15 ml high-density polyethylene test tubes with pressure caps and
kept dark and refrigerated at 4 deg. C without preservative. All
samples were analyzed directly in the test tubes within 24 hours
after sampling. Tests done for effects of analysis delay showed
variations for all nutrients  not significantly different to the
precision for each analysis.
	


C.5 	Measurements of Dissolved Carbon Dioxide and Carbon Isotopes

		By Reidar Nydal and Jorunn S. Gislefoss

Sampling strategy and procedure
The main goal for the cruise was to get some basic carbon profiles
north and south of the Greenland-Scotland Ridge, as a contribution to
the study of water overflow. It was especially important to repeat
three GEOSECS profiles from 1972. Fairly complete carbon profiles
were performed at 8 stations (933, 934, 937, 942, 943, 948, 955 and
961) Stations 933, 948 and 955 coinside with earlier GEOSECS stations
(sta. 19,11 and 14). The changes in profiles during a period of 20
years could give  valuable information  about water exchange with
depth.

 The samples were collected in 500 ml glass bottles, which first were
rinsed with some of the sampling water, and then filled up. The
samples were stored in a refrigerator and analysed within a few days.

Equipment and technique

The extraction of total dissolved carbon dioxide from 500 ml seawater
was carried out onboard shortly after collection. A bubbling
procedure with nitrogen (99.99%) as a carrier gas, in a closed cycle,
was applied for this purpose. The sample was acidified in advance
with phosphoric acid to a pH value of 1.5. The bubbling lasted for 15
minutes. The water was removed from the carbon dioxide gas using
vapor traps (-80 degrees C) and a drying agent. Carbon dioxide was
continuously trapped with liquid nitrogen (-196 degrees C) during the
cycle. After the flushing was finished nitrogen was removed and the
CO2-gas was trapped in 25 ml  glas ampulles for later measurements in
the laboratory after return.

The quantitative measurements of the CO2-gas are performed with an
oil manometer. The obtained precision (standard error) in a single
measurement, derived from several measurements on identical samples,
has been found to be less than 3 permill. The present procedure for
CO2 extraction is developed at the Radiological Dating Laboratory.

The obtained CO2-gas (ca 25 ml) is applied for both C14/C12 and
C13/C12 Accelerator Mass Spectrometry (AMS)  measurements (ca 2 ml).

DELC13

 The  DELC13  is the relative difference in permill between the
C13/C12 ratio in the sample and the international Belemnite  standard
(PDB):

			DEL13C = 1000 (RSA-RST)/RST

where RSA = C13/C12 for sample and RST = C13/C12 for standard.

The DELC13 measurements are performed at the Dating Laboratory at the
University of Helsinki, using a Finnigan MAT Delta E mass
spectrometer. Approximately 5 ml CO2 gass (from the DIC) was used for
the analysis. The instrument usually gives a precision of 0.02
permill, but the total precision for a single  measurement is
certainly larger (about 0.1 permill). This stable isotope is also
important as a tracer in study of carbon exchange, as we here obtain
the true C13/C12 ratio of the DIC fraction in the samples.

DELC14 (corrected)

The DELC14corr.  is expressed with the equation

		DELC14corr = DEL14C - 2 (DEL13C + 25) ( 1 + DELC14/1000)

Profiles of DEL14Ccorr. were obtained in 1972 in the GEOSECS
expedition . It is therefore important to obtain  profiles to day, to
compare the differences that has occurred during these 20 years.
These differences  can give important information about the ocean
circulation.  AMS on 5 ml of the CO2 gas (from DIC), were performed
at the University of Arizona (Slota et al., 1987).

Slota, P.J., A.Jt. Jull,  T.W. Linick and L.J. Toolin. 1987.
Preparation of small samples for 	C14 accelerator targets by
catalytic reduction of CO. Radiocarbon, 29 (2): 303 - 306.

C.6 	Total dissolved Inorganic Carbon , Partial pressure
                   of Carbon dioxide in Seawater.

		By Jon Olafsson and John Goddard.

Total Dissolved Inorganic Carbon

Total CO2 measurements are made on descrete seawater samples
collected at various depths. An approximately 20 ml  subsample is
injected by positive displacement syringe into a stripping column.
Acidification converts all inorganic carbonate species in the sample
into a CO2 gas which is then swept into an electrochemical titration
cell. The titration results are measured using a Utopia Instruments
Corp. (UIC) model 5011 Coulometer. The performance of the instrument
is monitored  several times daily using a gas loop calibration
system. Overall analytical quality control is evaluated daily with
reference material for oceanic CO2 measurements. This reference
material was kindly supplied by Dr. A. Dickson of Scripps Institution
of Oceanography, USA. After final processing, results are reported as
TCO2  UMOL/KG.

Partial Pressure of Carbon Dioxide in Seawater (pCO2).

The pCO2 analysis system uses a closed system seawater equilibrator
to bring the partial  pressure of CO2 of discrete seawater samples
into equilibrium with a small quantity of air, and a gas
chromatograph to analyze the concentration of CO2 in the equilibrated
air. The gas chromatograph  uses a flame ionization detector  (FID),
which is insensitive to CO2, but which has a highly linear response
to hydrocarbons. Using hydrogen as a carrier gas and a  ruthenium
catalyst, the CO2 is converted completely to methane prior to
reaching the FID. The highly sensitive and linear FID is thus used to
quantify the CO2 content of the equilibrated air. The discrete
seawater samples are collected in 500 ml flasks and are equilibrated
at a constant temperature bath at 20 degrees C. After corrections and
final processing, results are reported as pCO2 UATM at 20 degrees C.

C.7	Halocarbon Tracer Measurements

		By Elisabeth Fogelqvist

Certain man-made and some naturally produced low molecular weight
halogenated hydrocarbons (halocarbons) have been determined in both
water and air samples during  the cruise. Four man-made tracer
compounds  (trancient tracers), namely clorofluorocarbons 11, 12
and 113 and carbon tetracloride, provide a most powerful tool for
studying timescales and magnitudes of large-scale oceanic subsurface
mixing and deep water renewal processes.

Water samples, drawn directly from the Niskin sampling bottles using
100 ml ground glass syringes, were analysed using a purge-and-trap
sample work-up technique followed by gas chromatographic separation
and detection. The separation  of these, and 10 other identified
halocarbons, was carried out  in a 75 metres long megabore open
tubular column. Detection of the compounds was performed using the
selective and very sensitive electron capture detector, giving
detection limits of the order of 0.01 pmol/kg for CFCs 11 and 12;
somewhat higher for CFC 113 and carbon tetrachloride.

C.8 	Helium/Tritium Sampling

		By  Markus  Frank

Tritium is the radioactive isotope of hydrogen. It decays with a
halflife of 12.43 years to the helium isotope He-3. The major source
of tritium was the nuclear weapon testing in the atmosphere mainly in
the 1960s.

At the seasurface He-3 concentrations usually are close to solubility
equilibrium with the atmosphere. Water isolated from the surface due
to convection will be enriched  in tritiogenic He-3 while spreading
along the isopycnals. The tritiogenic He-3 is detectable as a
deviation of the He-3/He-4 ratio of the water sample from that of an
air standard. Measurements of  both He-3 excess and tritium
concentration allow calculation of formal tritium/he-3 age, whioch is
a tool for estimation of mean  transfer times, current speeds and
renewal times.

During the cruise  122 samples for measurement of both helium and
tritium were taken. The helium samples  (volume about 40cc) were
stored in copper tubes closed tightly at both ends by means of
special stainless steel pinch-off clamps.
 
For tritium analysis one liter of water was stored in a glass bottle
sealed by a polyethylene cap.

The analyses will be performed at Univ. of Heidelberg. For
measurements of He-3/He-4 ratio a special helium isotope mass
spectrometer with an accuracy of about  0.2 % is used.Tritium
measurements in Heidelberg are either done by low level counting
(with an accuracy of 5%) or by mass spectrometry (He-3 ingrowth
method with an accuracy of about 2 % and a detection limit of 0,05
TU).



D.	Acknowledgments

E.	References

	
References

Culberson, C.H. (1991) Dissolved Oxygen. In: WOCE Operations Manual.
   Vol.3, Section 3.1, Part 3.1.3: WHP Operations and Methods. WOCE
   Report No. 68/91, Woods Hole.  

Foyn, L., M. Magnussen and K. Seglem, 1981. Automatic analysis of nutrients 
   with an on-line dataprocessing. A presentation of the building and 
   functioning of the system  used at the Institute of Marine Research. 
   Fisken Hav.,Serie B, 1981 (4) : 1-39.( In Norwegian).  

Strickland, J.D.H. and T.R. Parsons, 1972.  A practical handbook of seawater 
   analysys. Bull. Fish. Res. Bd. Canada. 167: 1-311.

Unesco, 1983. International Oceanographic tables. Unesco Technical Papers in 
	Marine Science, No. 44.

Unesco, 1991. Processing of Oceanographic Station Data. Unesco memorgraph
	 By JPOTS editorial panel.

F.	WHPO Summary

Several data files are associated with this report.  They are the ar18.sum, 
jh1092.hyd, jh1092.csl and *.wct files.  The jh1092.sum file contains a 
summary of the location, time, type of parameters sampled, and other pertinent
information regarding each hydrographic station.  The ar18.hyd file contains 
the bottle data. The *.wct files are the ctd data for each station.  The *.wct 
files are zipped into one file called jh1092wc.zip. The jh1092.csl file is a 
listing of ctd and calculated values at standard levels.


The preliminary *.csl files are not availiable at this time due to the ctd
data being given in non-uniform levels.


G.	Data Quality Evaluation