Neptune effect: statistical mechanical forcing of ocean circulation

Abstract

Beginning from a particular concern about the role of pressuretopography correlations in coastal dynamics, for which the whimsical term "Neptune effect" arose, a broader and more powerful context unfolded. It has become clear that this effect has strength comparable to wind or thermohaline forcing, yet it is absent or grossly corrupted in even the most powerful computer models. A novel approach considers idealized statistical mechanics, then takes account that applied forces such as wind or thermohaline will draw the state of the ocean away from a higher entrophy configuration. Nonequilibrium tendencies which arise due to departure from higher entrophy serve to parameterize unresolved eddy effects. Introduction into conventional ocean models leads to large differences which markedly improve model skill measured against a global inventory of long term current meter records.