vis. Code Visibility according to WMO Code 4300. 



No. obs. depths Number of observed levels associated with the station. 



Messenger time Entered in hours and tenths of an hour GMT. For Nan.sen 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 thermometrically ; 



Z Indicates uncorrected "wire out" depth. Postscript Q indicates value was marked 

 doubtful by originator ; P indicates value was considered doubtful by NODC. Post- 

 scripts P and Q retain this meaning throughout the following entries. 



T ° C Temperature to hundredths of a degree Celsius. 



S °/oo 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. 



2AD Dyn. MX 10' Multiply entry by 10"' to obtain anomaly of dynamic depth in dynamic meters referenced 



to the seasurface. 



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



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