Studies of multiple equilibria in ocean-atmosphere-ice simulations of aquaplanets

Massachusetts Institute Of Technology, Cambridge MA

Investigators

Abstract

An hierarchy of intermediate coupled climate models will be used to investigate multiple equilibrium states of the climate system, the role of ocean heat transport in mediating the latitudinal range over which stable ice caps can extend, and the stability of the equilibrium states. The modeling framework is a coupled atmosphere, ocean and sea-ice model of an aquaplanet where the geometrical constraints on ocean circulation and extent of land are represented by a sequence of barriers. Key components of the ocean circulation, such as subtropical gyres, zonal jets, and meridional overturning circulation will be controlled by altering the geometrical barriers in the ocean. Their impacts on the mean state of the coupled system and its ability to sustain polar ice caps and multiple equilibrium states will then be examined. The proposal addresses fundamental questions about the energy balance of the planet, the processes that sustain polar sea-ice, interaction with the ocean and multiple equilibrium of the coupled climate system.