What Can Geoengineering Tell Us About Tropical Climate Dynamics?

Spencer and Ming (2012) studied the equilibrium climate response to a geoengineered brightening of marine stratocumulus clouds. A somewhat striking finding was that the global-mean surface temperature change normalized by the corresponding forcing (i.e., climate sensitivity to a highly localized forcing) is substantially higher for East Pacific than for North Pacific or East Atlantic. Here we design a set of climate model simulations to elucidate the physical mechanisms underlying the propagation of a regional surface temperature anomaly. The roles of moist convection, upper tropospheric mixing and tropical stability are highlighted. Also discussed are the implications for understanding regional precipitation patterns.