Ray Schmitt’s introduction to this issue underlines the importance of including the oceanic component of the hydrological cycle in considerations of Earth’s climate. Spatial and temporal salinity variations play an important role in diapycnal (across-density-surface) mixing, affecting property distributions and ocean circulation, which may in turn affect the atmosphere through sea-surface temperature.

Lukas, R., and F. Santiago-Mandujano. 2008. Interannual to interdecadal salinity variations observed near Hawaii: Local and remote forcing by surface freshwater fluxes. Oceanography 21(1):46–55, https://doi.org/10.5670/oceanog.2008.66.

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