TITLE = HLY-02-01-DOC.txt & HLY-02-03-DOC.txt

AUTHOR = Dr D.A. Hansell
University of Miami
Rosenstiel School of Marine and Atmospheric Science
Division of Marine and Atmospheric Chemistry
4600 Rickenbacker Causeway
Miami, FL 33149
Tel: 1-305 361-4078
Fax 1-305 361-4689
http://www.rsmas.miami.edu/groups/organic-biogeochem/

Dr N.R. Bates,
Bermuda Biological Station for Res. Inc.
17 Biological Lane
St George's GE01
Bermuda
Tel: 1-441 297-1880 (x210)
Fax: 1-441 297-8143
nick@bbsr.edu
http://www.bbsr.edu/Labs/co2lab/co2main.html

DATA CONTACT = Dr D.A. Hansell
University of Miami
Rosenstiel School of Marine and Atmospheric Science
Division of Marine and Atmospheric Chemistry
4600 Rickenbacker Causeway
Miami, FL 33149
Tel: 1-305 361-4078
Fax 1-305 361-4689
http://www.rsmas.miami.edu/groups/organic-biogeochem/

FUNDING SOURCE AND GRANT NUMBER = NSF OPP-0124900

DATA SET OVERVIEW =
Dissolved Organic Carbon.
-HLY-02-01 are the data for the SBI Spring cruise (8 May 2002 to 12 June 2002)
-HLY-02-03 are the data for the SBI Summer cruise (18 July 2002 to 21 August 
2002)
Both cruises were in the Chukchi Sea and Beaufort Sea on board the USCGC 
Healy.
Individual data point locations are identified with decimal latitude, longitude and 
depth (m).

INSTRUMENT DESCRIPTION =
Shimadzu TOC-VCSH.

References:  http://www1.shimadzu.com/products/lab/toc.html


DATA COLLECTION AND PROCESSING =
Samples were collected at most depths of the service hydrocasts. The DOC 
(dissolved organic carbon) samples were collected approximately 30-60 minutes 
after the CTD rosette reached the surface by gravity filtration through pre-
combusted (450C, 5 hours) 47 mm GF/F filters into acid washed 60 milliliter 
HDPE bottles.  The water samples were stored frozen at -20C until laboratory 
analysis.  DOC samples were analyzed by high temperature oxidation (HTO) 
using a Shimadzu TOC-VCSH Total Organic Carbon Analyzer.  Prior to analysis, 
the samples were acidified (10 l of 85% H3PO4 per 10 ml of sample) and 
sparged with CO2 free ultra pure oxygen (1.5 minutes) to remove any inorganic 
carbon.  One hundred ?l of seawater was injected into a quartz combustion tube 
that was packed with platinum gauze, 10 cm of Shimadzu's regular sensitivity 
platinum catalyst (7% Pt on alumina balls), and platinum mesh.  The combustion 
column was maintained at 680C, and ultra pure oxygen (150 ml/min) was used as 
the carrier flow.  The system was calibrated using potassium hydrogen phthalate 
(KHP) as the carbon source.  Typical blank values were less than 8 ?mol/l.  On a 
daily basis, the blank and deep sea reference water (described below) were 
analyzed and the system was recalibrated using the KHP standard when the results 
of these references materials fell outside expected range.  Typically, after the 
system was properly conditioned, recalibration was not necessary until the 
combustion tube was repacked.  Deep Sargasso Sea water (>2000 meters) that had 
been acidified and sealed in 10 ml ampoules was used as a reference material for 
this analysis.  This reference material has been analyzed by several laboratories 
and a consensus value (44-46 ?mol/l) determined for the organic carbon of this 
reference.   Analyzing this reference material several times per day along with the 
unknown samples provides a means for assessing instrument performance and the 
validity of the data.  Precision on the analysis was determined to be  2%. 

?

DATA FORMAT = Tab delimited ASCII files containing Dissolved Organic 
Carbon (DOC) data from the two 2002 SBI Arctic cruises.  HLY-02-01 was the 
spring cruise and HYL-02-03 was the summer cruise.  DOC data reported in 
?mol/liter.

DATA REMARKS = Quality flag 2 are good data.  Missing data are -9999.