Sigma-tVariable Name ⤴

Density of seawater calculated with in situ salinity and temperature, but pressure equal to zero, rather than the in situ pressure, and 1000 kg/m^3 is subtracted. Defined as (S,T)-1000 kg m-3, where (S,T) is the density of a sample of seawater at temperature T and salinity S, measured in kg m-3, at standard atmospheric pressure.