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OCADSColumn Header Standards for Underway Data

Table 2. Column header abbreviations, their preferred units, and brief descriptions for surface underway based chemical oceanographic data. "N/A" is short for "not applicable". Users can go to the "Resources" tab and click the "Quality Control Flags" collapsible to access the definitions of the quality control flags.

EXPOCODE N/A Expedition code (EXPOCODE) consists of the four-digit International Council for the Exploration of the Sea (ICES) platform code and the date of departure from port (UTC) in YYYYMMDD.
Cruise_ID N/A Cruise identification
Year_UTC N/A Calendar year in Coordinated Universal Time (UTC)
Month_UTC N/A Calendar month in Coordinated Universal Time (UTC)
Day_UTC N/A Calendar day in Coordinated Universal Time (UTC)
Time_UTC [hh:mm:ss] Time in the format of hh:mm:ss
Yearday_UTC N/A Yearday refers to the day number in an annual cycle. (e.g., 12 pm on Jan 1 means Yearday = 1.50, 6 am on Dec 31 means Yearday = 366.25 in a leap year). Two digits after the decimal point are recommended.
Latitude decimal degree Latitude in decimal degrees North (negative for Southern Hemisphere)
Longitude decimal degree Longitude in decimal degrees East (negative for Western Hemisphere)
Depth m Depth in meters
SST_ITS90 degree Celsius Sea surface temperature (usually intake temperature)
SSS_PSS78 N/A Sea surface salinity
Pressure_ATM hPa Sea level atmospheric Pressure
Temperature_EQU_ITS90 degree Celsius Water temperature recorded in the equilibrator
Pressure_EQU hPa Pressure inside the headspace of the equilibrator. 1 hPa = 1 mbar.
xCO2_EQU μmol/mol Mole fraction of carbon dioxide (dry) inside the headspace of the equilibrator
xCO2_ATM μmol/mol Mole fraction of carbon dioxide (dry) in the atmosphere
xCO2_ATM_interpolated μmol/mol Interpolated atmospheric xCO2 to match with water analyses time
fCO2_SW_SST μatm Fugacity of seawater carbon dioxide at SST
fCO2_SW_flag N/A Quality control flag for fugacity of seawater carbon dioxide
fCO2_ATM_interpolated μatm Interpolated atmospheric fCO2
dfCO2 μatm Delta fCO2 between seawater and atmosphere (fCO2_SW - fCO2_ATM)
pH_T_insitu N/A pH on total scale at in situ temperature
pH_flag N/A Quality control flag for pH_T_insitu
Oxygen μmol/kg Dissolved oxygen measured from sensor
Oxygen_flag N/A Quality control flag for dissolved oxygen
Percent_O2 N/A Percent O2 measurement made in equilibrated air
Percent_O2_flag N/A Quality control flag for Percent_O2
Chl_a μg/L Chlorophyll a concentration
Chl_a_flag N/A Quality control flag Chlorophyll a concentration

Click here to access the data file (xlsx) example.

* A newly developed program called fCO2_Calc is available to standardize the calculation of partial pressure of carbon dioxide (pCO2) and fugacity of carbon dioxide (fCO2) from molecular ratio (mole fraction) of carbon dioxide in dry air (xCO2) measurements (Credit: Denis Pierrort of NOAA/AOML).

Last modified: 2023-04-11T16:00:25Z