EX0839 Readme Class of Data: Surface ocean carbon dioxide concentrations Dataset Identifier: EX0839 Expocode: 33KF20081201 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: EX0839/Explorer Data quality issues: During a 22 hour time period (17:30 on 9 December to 15:45 on 10, December 2008) the flow of seawater was highly variable. This symptom is indicative of an "air bound" state: air is regularly pulled into the inlet to the seawater pump, which loses its prime. The discontinuous flow resulted in widely variable CO2 concentrations in the equilibrator headspace. Many of the data were flagged as bad and deleted. Some data were included in the reported data set, but were flagged as questionable. Several times during the transits between islands, the air analyses were slightly higher than expected. Terrestrial influence of the atmospheric CO2 concentrations was suspected, and the results are reported. 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 (300 ppm, 360 ppm, and 420 ppm) should be considered approximate (5 ppm). While individual data points above 420 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 CA02020 458.04 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)361-4382 Kevin.Sullivans@noaa.gov Timestamp for dataset reduction: 1/09/2009 Timestamp for most recent update of dataset: 1/09/2009 Time period the dataset refers to: 12/01/2008 - 12/11/2008 Geographic area the dataset refers to: Day 1 - Bayonne, New Jersey (40.7 N/74.1 W) Day 4 - San Juan, Puerto Rico (18.5 N/66.1 W) Day 5 - Charlotte Amalie, St. Thomas (18.3 N/64.9 W) Day 6 - Philisburg, St. Maarten (18.0 N/63.0 W) Day 7 - Rouseau, Dominia (15.3 N/61.4 W) Day 8 - Bridgetown, Barbados (13.1 N/59.6 W) Day 9 - St. John, Antigua (17.1 N/61.8 W) Day 13 - Bayonne, New Jersey (40.7 N/74.1 W)