Messenger time Entered in hours and tenths of an hour GMT. For Nansen casts, indicates time of 



release of messenger applicable to the observational level. For STD casts, indicates 

 the starting time of lowering the sensor. 



Card type OBS designates observed levels. STD indicates the values at this standard level were 



interpolated by a modified 3-point LaGrange formula. 



Depth (m.) Depth to nearest meter. A postscript T indicates depth was obtained thermometri- 



cally; Z indicates uncorrected "wire out" depth. Postscript Q indicates value was 

 marked doubtful by originator; P indicates value was considered doubtful by 

 NODC. Postscripts P and Q retain this meaning throughout the following entries. 



T ° C. Temperature to hundredths of a degree Celsius. 



S %o Salinity in parts-per-thousand. 



SIGMA-T Entered to hundredths. 



Specific-volume Multiply entry by 10-' to obtain specific-volume anomaly in cubic centimeters per 



gram. 



2; AD Dyn. M. X 10' Multiply entry by 10-^ to obtain anomaly of dynamic depth in dynamic meters 



referenced to the sea surface. 



Sound Velocity Sound velocity according to Wilson's formula to tenths of a meter per second. 



0,_, ml./l. Dissolved oxygen in milliliters per liter entered to hundredths. 



PO^-P /ig-at/I. Inorganic phosphate in microgrram-atoms per liter entered to hundredths. 



Total-P /ig-at/1. Total phosphorus in microgram-atoms per liter entered to hundredths. 



NO2-N ^g-at/1. Nitrite-nitrogen in microgram-atoms per liter entered to hundredths. 



N0.1-N /ig-at/1. Nitrate-nitrogen in microgram-atoms per liter entered to tenths. 



SiO^-Si ^g-at/1. Silicate-silicon in microgrram-atoms per liter entered to whole units. 



pH Entered to hundredths. 



30 



