Climate science: Unexpected fix for ocean models.

Abstract

Computational models persistently underestimate strong currents that redistribute ocean heat. This problem is solved in models in which ocean eddies are damped by coupling of the atmosphere with the sea. See Letter p.533 Ocean currents are considerably stronger on the western sides of ocean basins than on the eastern sides, owing to an ocean-dynamic process known as western intensification. Western boundary currents convey tremendous amounts of heat towards the poles and drive extensive ocean mixing. Yet most coupled climate models systematically underestimate these currents. Ping Chang and colleagues now show that this problem can be addressed by resolving not only ocean mesoscale eddies, but also their interaction with the atmosphere, a factor that is unresolved in current-generation climate models. Strong coupling between the ocean and the atmosphere ensures that eddy energy is efficiently dissipated in high-resolution models, producing an appropriately vigorous current, in this case for the Kuroshio Extension Jet.