Preliminary data Report
March 28, 1995

                                CRUISE REPORT

A. 	Cruise Narrative

A.1	Highlights

A.1.a	WOCE designation:  AR16

A.1.b	Expedition Designation: 06HF991/1, 06HF991/2, 06HF991/3,  
                                
A.1.c	Chief Scientists:  
        Leg 1: Hans-Christian John, BAH  
        Leg 2: Hans Georg Andres, BAH  
        Leg 3: Hans-Christian John, BAH  
        Address for Both Chief Scientists
	Taxonomische Arbeitsgruppe der Biologischen Anstalt Helgoland
	c/o Zoologisches Institut und Museum
	Martin-Luther-King-Platz 3, 20146
	Hamburg, Germany
	Phone: 040/41232287 or 41235642
	Fax: Zim 040/41233937

A.1.d	Ship:   R/V Heincke

A.1.e	Ports of Call:  
        Leg 1: Cuxhaven, Germany to Leixoes, Portugal  
        Leg 2: Leixoes to Lisboa, Portugal  
        Leg 3: Lisboa to Leixoes  
        

A.1.f	 Cruise Dates  
        Leg 1: March 9 to March 20, 1991  
        Leg 2: March 22 to March 28, 1991  
        Leg 3: April 1 to April 11, 1991  
        Leg 4: April 13 to April 20, 1991

A.2	Cruise Summary

A.2.a	Geographical boundaries

			43 53.00 N
	10 50.00 W			08 45.00 W
			38 27.00 N

A.2.b	Total number of stations occupied

During the cruise a total of 132 CTD/rosette stations were occupied using 
a CTDO equipped with a 12 position rosette with 2.7 liter teflon water 
sampling bottles.

A.2.c	Floats and drifters deployed

A.2.d	Moorings deployed or recovered

A.3	List of Principal Investigators

Principal Investigator

        CTDO    Eberhard Hagen  IfMW

A.4 	Scientific Programme and Methods 

    The following report deals only with the CTD-measurements and the water  
sampling for sensor calibration, because this was the part of our institute  
during the cruise. Biological measurements and moorings had been done by the  
colleges of BAH and BSH (Bundesamt fuer Seeschiffahrt und Hydrographie, 
Hamburg).

Measurements
    CTDO and sound speed; salinity and oxygen of water samples; temperature 
and  pressure by reverse deep sea thermometers.

Rationale and history
    The cruise started in Cuxhaven, Germany on 09. March 1991 and ended at the 
island of Helgoland, Germany on 20. April 1991. Foreign ports of call were  
Leixoes (twice) and Lisboa, where the ship received visits from Portuguese  
scientists and students.
    This cruise was the third in sequence within a cooperation existing since  
1987 between "Biologische Anstalt Helgoland" and the University of Lisboa on  
the seasonal dynamics in the Portuguese upwelling area. The cruises are  
designed to investigate eastern boundary currents in the temperate Northeast  
Atlantic and the seasonal dynamics of plankton and hydrography off the western
Iberian Peninsula.
    Eastern boundary current systems with coastal upwelling are important  
fishing areas worldwide. They have in common at least seasonally (off Portugal
during summer) a coast-parallel wind stress, forcing offshore Ekman transport  
at the surface. The resulting mass-deficit close to the coast is partly  
compensated by an intermediate compensating current onshore. Fish larvae are  
transported both by the Ekman drift and the compensating current. Drift is  
probably one of the mechanisms affecting larval survival. The compensating  
current feeds cold and nutrient-rich water into the euphotic layer and thus  
enhances primary production, used by successive steps in the food web up to  
exploited fish populations. Upwelling areas have generally a somewhat  
impoverished specific diversity and show equatorward shifts of faunistic  
boundaries.
    In a larger context this study shall at the time of the "World Ocean  
Circulation Experiment (WOCE)" contribute to the study of the Eastern Boundary
Currents off the Iberian Peninsula and (later) off Morocco. Questions are:

1. Which variability and interactions in time and space exist within the  
   system?
2. Does the poleward undercurrent described south of 26°N also exist off  
   Morocco?
3. Is there a direct connection between the African undercurrent and the  
   undercurrent observed off the Iberian Peninsula?
4. How far are distributions and drift of zooplankton and fish larvae  
   influenced by this current system?

Narrative
    The following research activities were carried out:
A) At hourly intervals meteorological data were automatically registered.  
   Intercalibration of automatic sensors was done daily.
B) 133 vertical CTD-profiles were made to 1500 m depth (or the bottom,  
   respectively) at all stations. The parameters pressure (P), 
   Conductivity (C), Temperature (T), dissolved oxygen (02) and sound velocity 
   (SV) were measured directly and salinity (S) was automatically derived. 
   In-situ calibration was done at each station for P, T, 02 and S. Repeated 
   measurements were made at survey lines C (three times) and D (twice).
C) 28 horizontal neuston net tows and 32 vertical plankton hauls by a multiple
   opening-closing net (1000 m depth or bottom) were made.
D) 107 oblique tows by the multiple opening-closing net (200 m or bottom) were
   made. Survey lines C and D were covered twice.
E) 52 biological box corers were taken along the survey lines C and D from the
   coastal stations to maximum bottom depths of 1450 m.
F) Raw-data evaluation was done for several parameters from the CTD along all  
   transects and for surface temperature and salinity at the "synoptic" 
   stations.
G) Macroscopical analysis of biological sampling was done for bathymetry and  
   substrate-dependence of ampeliscid amphipods from the box corers and the  
   distribution in space and time of clupeoid fish larvae from plankton tows.
H) Long-term current meter moorings (to be recovered in February, 1992) were  
   laid at bottom depths of about 2000 m.  
   Recording depths (6 instruments each) are from the bottom to 200 m.
I) Short-term current meter moorings were laid at the positions K1 and K2.  
   Mooring Kl was recovered at the end of the cruise (3 instruments, bottom to 
   40m), mooring K2 was lost.  The biological material was for analysis in the 
   laboratory and subsequent joint publication split between the Portuguese 
   and German participants. The more detailed German cruise report and all 
   accompanying environmental data available so far are also in hands of the 
   Portuguese counterparts. There is mutual agreement to continue this project 
   and the common desire to expand it including smaller scale future studies.


A.5	List of Cruise Participants

		Table 1: List of Cruise participants

Name			Responsibility			Affiliation
-------------------------------------------------------------------
H.-G. Andres						BAH
R. Bahlo		CTD Hardware			IfMW
H. Giese						BSH
E. Goncalves						UL
W. Hub			Salts				IfMW
H. -Ch. John						BAH
M. Kloppmann						BAH
J.C. Marques						UC
E. Mittelstaedt						BSH
H. Petersen						BAH
P. Re							UL
G. Schilling		CTD Software			IfMW
F. Zapp			Oxygens				IfMW
-------------------------------------------------------------------
* See table 2 for list of Institutions

		Table 2: List of Institutions

Abbreviation			Institution
------------------------------------------------------------------
BAH				Biologische Anstalt Helgoland
				Martin-Luther-King-Platz 3
				Hamburg, Germany  20146

BSH				Bundesamt fuer Seeschiffahrt und
				Hydrographie
				Postfach 30 12 20 
				Hamburg, Germany D-20305

IfMW				Institut fuer Meereskunde Warnemunde
				Seestr. 15
				D-18119 Rostock-Warnemande
				Germany
				
UC				University of Coimbra
UL				University of Lisboa
--------------------------------------------------------------------


C.	Hydrographic Measurements

C.1	CTDO

The CTDO and the sensors are manufactured at the institu fuer
Meereskunde Warnemuende, Germany.  The CTDO is an OM-87 = Oceanological
Measuring System, consisting of an expandable dividing CTDO-probe,
interfaced through a special designed slave-computer, a meteorological
subsystem interfaced by a second slave-computer and a master-PC.  The
IfMW meteorological subsystem interfaced by a second slave-computer and
a master-PC.  The IfMW began to develop oceanographic measuring systems in
the 1960's.  The first computer controlled CTD-system, OM-75 (Moeckel,
1980) was taken into service in 1976.  The new generation: OM-87 has
been used since 1988.

The CTD is equipped with frequency-analogous sensors at standard ports,
developed and manufactured by IfMW; the oxygen sensor together with FSI
"Kurt Schwabe", Meinsberg, Germany.

C.1.a	Sensor Configuration List

The various sensors used on the different CTDs are listed in Table 3
by station and CTD number.


			Table 3:  CTD sensor configuration

CTD/Stat. No. 		Parameter	Sensor	Resolution	Precision
--------------------------------------------------------------------
CTD No. 2		Pressure	P251	0.1 dbar	2dbar
CTD No. 3/Sta 161	Pressure	P252	0.1 dbar	2dbar
CTD No. 2/Sta. 161	Temp		T103	0.0015 K	0.01 K
CTD No. 2/Sta. 161	Xonductivity	C853	0.0008MS/cm
CTD No. 2/Sta 161	Xxygen		0022	0.01 ml/l	0.1 ml/l
CTD No. 2/Sta. 137	Sound Speed	V116	0.025m/s	0.3 m/s
CTD No. 2/Sta. 139-141	Sound Speed	V116	0.025m/s	0.3m/s
CTD No. 2/Sta. 147-161	Sound Speed 	V143	0.025m/s	0.3m/s 
---------------------------------------------------------------------

All sensors were calibrated before the cruise at the calibration
laboratory of IfMW.  The oxygen sensor was recalibrated during the
cruise at the first station with water samples.  The calibration
constants of all sensors were checked up by the in situ comparisons of
p, T, C, O2.  

B.1.b  	CTDO

The down cast data were recorded on hard disk.

Sampling rate: 1 record in 1.2s = 0.83 HZ integration time of sensors:
1s lowering speed of CTD: 1.0 m/s time constants: pressure and
temperature sensors = 0.1 s conductivity sensor = 0.1 s at 1 m/s
lowering speed.

The calibration constants of pressure, temperature, conductivity, sound
speed sensors and the recalibration constants of the oxygen sensor were
used over the whole cruise.  The check measurements of CTDO and water
sample data (in situ comparisons) were used for calculating the
post-cruise corrections.

B.1.c	Post-Cruise CTD Data Processing

The raw data are digitized frequencies, which had been converted to
physical units of pressure, temperature, conductivity, oxygen and sound
speed.  A validation routine was applied to the CTDO down cast data
(LASS et al., 1983), to eliminate:

1. data values, which are not physically realizable.

2. Random errors by recursive low-pass filtering (Acheson, 1975).

3. Systematic errors caused by the effect of ship's rolling and
   pitching on the lowering rate of CTD.  Records acquired while CTD is
   moving down too slowly have been discarded to enforce a strict
   monotonic sequence in pressure.  The so called eddy-algorithm in
   connected view with the values of sensor integration time and lowering
   rate reduce the effect of different time lags of the sensors to minor
   importance. 

The calculation of salinity from conductivity and conversion of
dissolved oxygen of volumetric to weight concentration were done last
after correcting the data as described below. Dissolved oxygen was
converted according to the WOCE Operations Manual (1991).

The data haven't been averaged finally in 2 dbar increments because of
the low sampling rate of the CTD and a great amount of discarded
records in the course of data processing, up to 50% on average.

C.1.d	CTD Post-Cruise Corrections

In order to get the CTDO to match the water sample and, respectively,
the thermometer data that following fits defined in Table ??? were
applied to the CTDO data.

C.1.e	CTD Errors and Noise

During the cruise two sensor failures were located.  After station no.
2 the pressure sensor had to be replaced and after station no. 146 the
sound speed sensor.  The sound data of station 138, 145 and 146 were
disturbed and have been discarded.

C.2	Water sampling for In Situ Comparisons

After finishing the down cast (CTDO-recording), the CTD was lifted and
stopped within well mixed layers.  After 10 minutes waiting to let the
deep-sea thermometers adapt to the surrounding temperature two water
bottles were tripped while a short time CTDO recording.  The deep sea
thermometers (2 protected and 2 unprotected) were reversed
simultaneously with the first bottle tripping.

When the first bottle of each sampling depth tripped correctly the
water samples ( 2 dissolved oxygen and 2 salinity) were drawn from
these bottles, otherwise from the second ones.

	Table 4: CTD calibration Coefficients
-------------------------------------------------------------------------
CTD No./Sta. No.	Sensor		Fitting		Fitting
					Parameter	Polynomials
-------------------------------------------------------------------------
pressure: offset-fit	PRES, fitted=A0+PRES
					A0
2			P251		0.0 (no fit)
3-161			P252		5.0

temperature: linear fit	TEMP, fitted=A0+A1*TEMP
					A0		A1
2-61			T103		0.02905		0.991986
72-161			T103		0.01525		0.993555

conductivity:linear fit	COND, fitted=A0+A1*COND
					A0		A1
2-61			C853		0.33395		0.991045
72-161			C853		0.26103		0.992632

Oxygen:linear fit ml/l	OXYG, fitted=A0+A1*OXYG
					A0		A1
2-61			O025		0.948		0.2236
72-161			O025		1.366		0.2136

Oxygen: Temp Correction(ml/l) OXYG, corr.=OXYG,fitt.+A0+A1*TEMP
					A0		A1
2-61			O025		1.0		-0.1
72-161			O025		1.1		-0.1
sound speed: no fit
2-144			V116
147-161			V143
--------------------------------------------------------------


C.3	Salinity

The water sample salinities were measured with a Guildline Autosal Model
8400A salinometer, manufactured by Guildline Instruments Ltd., Smiths
Falls, Canada.  The salinometer was standardized weekly with IAPSO
Standard Seawater (SSW) Batch P 111.  Differences in standardization
readings were less than 3.

The salinometer manufacturer claims a precision of 0.002 and am
accuracy of better than 0.003; better than 0.001 when the laboratory
temperature is constant (=/- K) and about 1-2 K below the bath
temperature of the salinometer.

Water samples were let to come to the ambient temperature before
measuring.  The laboratory was temperature controlled (+/-1...2 K),
1...2 K below the bath temperature.

C.3.a

The laboratory temperature was 20 C constant (+/-1...2 K)

The temperature of salinity samples was determined before measuring
conductivity. Oxygen samples had equilibrated to room temperature when
measured. 

C.3.b	Standards Used

IAPSO Standard Seawater, P111, Feb 7, 1989.

C.4	Oxygen

The dissolved oxygen samples were analyzed by the Winkler Titration
Method modified by Carritt and Carpenter (1966).

C.5	Temperature

The following reverse thermometers were used:

Manufactured by: VEB Thermometerwerk Geraberg, Germany

			scale		graduated in
pressure protected    -2...+30degC        0.1K
unprotected	      -2...+30degC	  0.1K

Manufactured by:  Gohla-Precision, Kiel, Germany

			scale		graduated in
pressure protected    -1..+35C		  0.1 K

C.6	Differences and Standard Deviation of Water Samples

The differences between the salinity and oxygen measurements of the
duplicate water samples and the standard deviation of the differences
are shown in Table 3:

			Table 5:  Sample variance
----------------------------------------------------------------------
Parameter		Average 	Maximum		Standard
			difference	difference	deviation
----------------------------------------------------------------------
salinity		0.0014		0.021		0.0022
oxygen			0.011		0.03		0.0083
-----------------------------------------------------------------------

D.	Acknowledgments
E.	References

Acheson, D.T., 1975.  Data Editing--Subroutine EDITQ.  NOAA Technical
Memorandum EDS CEDDA-6.

Lass, H.U., Wulff, C., Schwabe, R., 1983. Methoden und Programme zur
automatischen Erkennung und Korrektur von Messfehlern in
ozeanologischen Vertikalprofilen.  Beitrage zur Meereskunde, Heft 48,
pp 95-111, Berlin.

Moeckel, F., 1980.  Die ozeanologische Messkette OM 75, eine
universelle Datenerfassungsanlage fuer Forschungsschiffee.  Beitraege
zur Meereskunde, Heft 43, pp 5-14, Berlin.

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

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

Wlost, K.-P., 1993.  The OM-87-System: a brief description.  Institut
of Baltic Reasearch Warnemnde, Germany. unpublished paper.

WOCE Operations Manual, Vol. 3, Sec.3.1, Part 3.1.2, 1991. WHP Office
Report WHPO 90-1, WOCE Report No. 67/91, Woods Hole, Mass., USA.

WOCE Operations Manual, Vol. 3, Sec 3.1, Part 3.1.3:  WHP Operations
and Methods; C.H. Culberson:  Dissolved Oxygen, WHP Office Report WHPO
91-1, WOCE Report No. 68/91,1991, Woods Hole, Mass., USA.

F.	WHPO Summary


Several data files are associated with this report.  They are the ebc1.sum, 
ebc1.hyd, ebc1.csl and *.wct files.  The ebc1.sum file contains a summary of
the location, time, type of parameters sampled, and other pertient
information regarding each hydrographic station.  The ebc1.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 ebc1.wct.zip. The ebc1.csl file is a listing
of ctd and calculated values at standard levels.

**NOTE:  A preliminary *.csl files were not created due to CTD data being
provided in non-uniform levels.
