SIO vessels collect MET (meterological system) underway data. These data include surface TSG measurements combined with fluorometry, pH, ship instrumentation (such as heading & speed) & meterological data. These values may be combined into 30 second records and collected into daily files. CTD near-surface data are used to correct underway temperature, salinity, & fluorometer measurements. Underway data is available in raw, 30sec MET ascii format and 10 minute binavg, corrected data.
NOAA vessels collect SCS data which may or may not be reported in a single, combined record during the cruise. Since data are sampled at different frequencies & into separate data files. post-cruise processing to a common time-scale is required. This requires significantly more effort which may delay the availability of the underway data products.
SIO-CalCOFI processes SIO, NOAA, and other CalCOFI ship underway data and convert the data into a universal ascii data format. Final underway data files contain both the processed ship specific averaged data and corrected values. Below are examples of column headers and their units.
Underway_Final.txt
DATE_UTC: DDMMYY
TIME_UTC: HHMMSS
LA or Lat: Latitude Decimal format Deg
LO or Long: Longitude Decimal format Deg
ST, t1, t2: Sea Surface Temperature Deg C
C: Condutivity S/M
SA or S: Salinity PSU
FL: Fluorometer ug/l
FI: USW Flow Meter LPM
CAL_T: Calculated Temperature Deg C
CAL_S: Calculated Salinity PSU
CAL_C: Calculated Chlorophyll A mg/m³