Sea Surface Salinity (SSS)
D1. Physical and chemical oceanography and marine meteorologyDefinition
Salinity of the upper few meters of the ocean.
Sea surface salinity is the salinity of the upper few meters of the ocean, now mapped from space by L-band radiometers (SMOS, Aquarius, SMAP) and in situ by Argo floats, ships, and drifters. SSS traces the surface freshwater cycle: evaporation raises it under the subtropical highs, precipitation and river runoff lower it under the ITCZ and near coasts. Surface salinity patterns are a fingerprint of an intensifying water cycle.