JGOFS Mat file Column # Name Note 9 Speed over ground, Knots 10 GPS HDOP 11 Gyro Heading, Degrees (azimuth) 12 Course made good, Degrees (azimuth) 13 Mast PAR, MkEinsteins/meter2 sec 14 Sea surface temperature, degC 15 Sea surface conductivity, siemens/meter 16 Sea surface salinity, PSU 17 Sea depth (uncorrected, calc. sw sound vel. 1500 m/s), meters 18 True wind speed (max speed windbird), meters/sec 19 True wind direction (max speed windbird), degrees (azimuth) 20 Ambient air temperature, degC 21 Relative humidity, % 22 Barometric pressure, mBars 23 Sea surface fluorometry, Mkg/l (mg/m3) 24 Transmissometry, % 25 PSP, W/m2 26 PIR, W/m2