Estimation of dynamic heights from temperature profiles in the Tasman Sea

Abstract

Three methods chosen to estimate dynamic height from temperature profiles in the Tasman Sea were: (1) simple linear regression of dynamic height relative to 1300 dbar (D_0/1300) on temperature at 250 m (T₂₅₀); (2) simulating salinity profiles from mean temperature-salinity (T-S) relationships to use with standard- depth temperatures such as Nansen casts to 1300 m; and (3) simulating salinity profiles from mean T-S relationships to use with expendable bathythermograph profiles to 450 m; and then linear regression of D_450/1300 on T₄₅₀ for the dynamic height below 450 m. The approximate dynamic heights, relative to 1300 dbar, were compared with the true dynamic heights (calculated in the normal way) at the 702 stations examined. Root-mean-square differences were shown to be 7-8, 24 and 5-5 dyn cm, respectively, for the three methods.