EX0941 Readme


Class of Data:  Surface ocean carbon dioxide concentrations

Dataset Identifier:  EX0941

Expocode: 33KF20091121

Statement of how to cite dataset:

     For information on dataset citation and more, please see Master Readme File.
     Explorer website: http://www.aoml.noaa.gov/ocd/gcc/explorer_introduction.php

Measurement platform identifier:  EX0941/Explorer

Data quality issues:

     During the stop at Port Canaveral, STD2 was replaced with a cylinder of higher
     pressure and concentration.  Several times during the cruise, air analyses were 
     done while there was not water flow, and so the sea surface temperature and 
     salinity sensors were not active.  For these intervals, values for sea surface 
     temperature (SST) and salinity (SSS) were assigned for data processing.  
     For the interval of 21 November 22:35 to 22:45, the assigned values for SST and 
     SSS were 13 C and 32, respectively.  For the intervals of 21 November 11:30 to 11:40
     and 17:05 to 17:15, the assigned value for SST was 23 C and for SSS was 36.  For 
     the interval of 21 November 20:24 to 23:22, the assigned value for SSS was 36.
     For the interval of 25 November 04:02 to 04:13, the assigned values for SST and 
     SSS were 23 C and 36, respectively.

    Some of the air analyses during the transit south to Port Canaveral were likely impacted 
    by terrestrial sources.  The results were included but flagged as "questionable".

     Standard Gases and Reference Gas:  The three standard gases come from CMDL
     in Boulder and are directly traceable to the WMO scale.  The reference gas
     is a non-calibrated gas from a commercial company.  Any value outside the
     range of the standards should be considered approximate (5 ppm).
     While individual data points above 460 or below 300 may
     not be accurate, the general trends should be indicative of the seawater
     chemistry.  The standards used on the cruise are:

           STANDARD          TANK #       CONCENTRATION       VENDOR
           STD1                                0.00         Commercial
           STD2 (1)         CA02020          458.04           CMDL
           STD2 (2)         CA07952          549.89           CMDL
           STD3             CA02040          319.82           CMDL                                               
           STD4             CA02030          377.14           CMDL                                               

     Units:  All xCO2 values are reported in parts per million (ppm) and fCO2
     values are reported in microatmospheres (uatm) assuming 100% humidity at the
     equilibrator temperature.


Contact person for this dataset:  

     Kevin Sullivan
     (305)361-4441
     Kevin.Sullivan@noaa.gov

Timestamp for dataset reduction:  8/10/2010

Timestamp for most recent update of dataset:  8/10/2010

Matlab version used for reduction: 1.05

Time period the dataset refers to:  11/21/2009 - 11/29/2009

Geographic area the dataset refers to:

   Day 1  - Bayonne, New Jersey (40.7 N / 74.1 W)
   Day 4  - Port Canaveral, Florida (28.4 N / 80.6 W)
   Day 5  - Nassau, Bahamas (25.1 N / 77.3 W)
   Day 6  - Co Co Cay, Bahamas (25.8 N / 77.9 W)
   Day 10 - Bayonne, New Jersey (40.7 N / 74.1 W)