Property-Property relations: 22 degree and 9 degree discontinuities in the Arabian Sea

Abstract

Property-property relations, mostly of conservative chemical parameters, are used in this attempt in tracing various discontinuities in the Arabian Sea and to reveal in situ processes together with potential temperature-salinity plots. Plots of salinity, PO, NO, oxygen and water stability (E) against potential temperature reveal that two discontinuity layers, one at 22.2 degrees C (22 DD) and the other at 9.1 degrees C (9 DD) are found in the Arabian Sea. 22 DD seems to have been formed due to the mixing of shallow salinity maximum water (SSMW) and Persian Gulf water (PGW). This discontinuity is situated in the centre of the mixing depth interval. Red Sea water (RSW) mass contributes chiefly for 9 DD. Various physico-chemical characteristics of these two discontinuity layers are elucidated, along with those of other water masses and density surfaces