3DATA DESCRIPTION FOR FILE \<Meteor60.csv\>

CONTRIBUTORS

Toste Tanhua

Leibniz Institute of Marine Sciences at Kiel University\
Marine Biogeochemistry\
Duesternbrooker Weg 20\
D-24105 Kiel,\
Germany\
Email: [ttanhua@ifm-geomar.de\
]{.underline}

Douglas W.R. Wallace (CHIEF SCIENTIST)

Leibniz Institute of Marine Sciences at Kiel University\
Marine Biogeochemistry\
Duesternbrooker Weg 20\
D-24105 Kiel,\
Germany\
Email: <dwallace@ifm-geomar.de>

SCOPE

Hydrographical and chemical data made during the German Meteor 60/5
cruise in the mid-latitude North Atlantic. Start of cruise:2004.0311.
End of cruise: 2004.04.13

# DATA DESCRIPTION

The methods, corrections and post-cruise calibration procedures are
described below.

CTD WORK

The temperature and salinity are reported on the ITS-90 and PSS-78
calibration scales, respectively. For more information regarding CTD
data, contact Jens Schafstall (<jschafstall@ifm-geomar.de>).

  -------------------------- ---------------------- ----------------------
  Instrument Type            SBE 11 plus            Serial No.

  CTD deck unit              SBE 9plus              

  CTD underwater unit        SBE 32                 09P22348-0572

  Rosette water sampler      SBE 3plus              3222348-0291

  Temperature sensor         4c                     03P2920

  Conductivity sensor        SBE                    042443

  Oxygen sensor              SBE 43                 430214

  Pump                       SBE 5T                 052603

  Pinger                     Benthos                

  Bottom alarm               mechanic switch        
  -------------------------- ---------------------- ----------------------

Bottle salinity were measured on a Guildline Autosal 8 salinometer. The
precision between replicate measurements were 0.003 units.

TOTAL ALKALINITY

Potentiometric titration \[Mintrop et al., 2000\].

CRM corrected from 4 separate batches (batch \# 58, 60, 63 and 64). The
mean difference between measurements and the Certified values was -1.19
± 0.69 μmol kg^-1^ (95% confidence interval, n=69). Alkalinity values
have been adjusted to the certified value by addition of this mean
offset. Precision of the total alkalinity single measurement was 4.28
μmol kg^-1^ (95% confidence interval), determined from measurements of
duplicate samples.

Based on cross over with contemporary CLIVAR cruises and with TTO/NAS,
we suggest that the total alkalinity is corrected by adding 1.6 umol/kg
from the original data (not applied to the submitted data).

The background and procedures of the correction is described in detail
by Tanhua and

Wallace (2005).

DISSOLVED INORGANIC CARBON (DIC)

Coulometric titration \[Johnson et al., 1993\].

CRM corrected from 4 separate batches (batch \# 58, 60, 63 and 64). Mean
offset between our measurements and the Certified Values was 1.02 ± 0.44
μmol kg^-1^ (95% confidence interval, n = 88). Measured DIC
concentrations were therefore adjusted to the manometric Certified
calibration scale by subtraction of this mean offset. Precision of the
measurements was 1.49 μmol kg^-1^ (95% confidence interval), as
determined from analyses of duplicate samples.

The background and procedures of the correction is described in detail
by Tanhua and

Wallace \[2005\].

OXYGEN

Oxygen measurements performed by Frank Malien (<fmalien@ifm-geomar.de>)
by means of Winkler titration. The precision estimated from double
samples (95 % confidence interval) is estimated to ± 0.55 μmol/kg.

NUTRIENTS

Nutrient analysis performed by Frank Malien (<fmalien@ifm-geomar.de>).

The following precision was calculated for the nutrient data (95%
confidence);

NO3 ± 0.18 μmol/kg and SIO2 ± 0.19 μmol/kg, calculated from measurements
of double samples.

The nutrient data was compared with crossover stations for contemporary
CLIVAR lines (A16, A22 and A20). Based on these cross over stations, we
suggest the following corrections to the nutrient data (not applied to
the submitted data).

M60 Silicate values too low in the high concentration range compared to
CLIVAR data, therefore we suggest the following corrections;

For Si\<20 μmol/kg; Si(corr)=Si

For 20\<Si\<30 μmol/kg; Si(corr)=Si+(Si-20)\*0.2

For Si\>30 μmol/kg; Si(corr)=Si+2

M60 nitrate values are low in the high concentration range compared to
CLIVAR data, therefore we suggest the following corrections;

NO3\<10 μmol/kg; NO3(corr)=NO3

NO3\>10 μmol/kg; NO3(corr)=NO3+(NO3-10)\*0.05

The PO4 data from M60/5 was subject to some analytical difficulties and
were of noticeably poorer quality than the other parameters, and are
flagged accordingly.

CFCs

The CFC measurements performed during M60/5 were made on an analytical
system similar to that described by Bullister and Weiss and are reported
on the SIO98 scale. The analytical precision was determined to be 0.7
and 0.6 % for CFC-12, CFC-11, respectively, as calculated from duplicate
samples, typically at two depths per station.

We determined a sampling blank of 0.007, 0.010 and 0.045 pmol/kg for
CFC-12, CFC-11 and CCl4, respectively, determined as the median value of
18 deep water samples in the eastern basin. The data has been corrected
for this sampling blank.

DATA FORMAT

The data are supplied in comma separated format (.csv).

The header records;

Sample ID, Station#, Cast #, Pressure (dbar), Day, Month , Year, Lat
(°N), Lon (°E), Temperature (ITS-90), Salinity (PS-78), CFC-12
(pmol/kg), CFC-11 (pmol/kg), CCl4 (pmol/kg), Oxygen (umol/kg), SiO4
(umol/kg), PO4 (umol/kg), NO3 (umol/kg), NO2 (umol/kg), DIC-calc
(umol/kg), Total Alkalinity (umol/kg).

Missing data are denoted with --999, the units for the revised data are
identical with the

original data.

OTHER MESUREMENTS

SF~6~ and CH~3~CCl~3~; Contact Toste Tanhua (<ttanhua@ifm-geomar.de>).

N~2~O; Contact Hermann Bange (<hbange@ifm-geomar.de>)

Carbon isotopes; Contact Douglas Wallace (<dwallace@ifm-geomar.de>)

Bioincubations; Contact Matt Mills
([mmills@ifm-geomar.de](mailto:mmilss@ifm-geomar.de))

Iron speciation; Contact Eric Achterberg (<eric@noc.soton.ac.uk>)

Brominated organohalgens; Contact Douglas Wallase
(<dwallace@ifm-geomar.de>).

REFERENCES

> Bullister, J.L. and Weiss, R.F., 1988. Determination of CCl3F and
> CCl2F2 in seawater and air. Deep-Sea Research, 35(5): 839-853.
>
> Mintrop, L., F.F. Perez, M. Gonzalez-Davila, J.M. Santana-Casiano, and
> A. Körtzinger (2000), Alkalintiy determination by potentiometri:
> intercalibration using three different methods, Scienc. Mar., 26, 1,
> 23-37.
>
> Johnson, K., K.D. Willis, D.B. Butler, W.K. Johnson, and C.S. Wong
> (1993), Coulometric carbon dioxide analysis for marine studies:
> Maximizing the performance of an automated gas extraction system and
> coulometric detector, Mar. Chem., 44 (2-4), 167-188.
>
> Tanhua, T., and D.W.R. Wallace (2005), Consistency of TTO-NAS
> Inorganic Carbon Data with modern measurements, Geophys. Res. Lett.,
> 32, L14618, doi:10.1029/2005GL032348.