Abstract

Uncertainty in the response of clouds to global warming remains a significant barrier to reducing uncertainty in climate sensitivity. A key question is the extent to which the dynamic component -- that which is due to changes in circulation rather than changes in the thermodynamic properties of clouds -- contributes to the total cloud feedback. Here, simulations with a range of cloud-resolving models are used to quantify the impact of circulation changes on tropical cloud feedbacks. The dynamic component of the cloud feedback is substantial for some models and is controlled both by SST-induced changes in circulation and nonlinearity in the climatological relationship between clouds and circulation. Differences in the longwave and shortwave dynamic components across models are linked to the extent to which ascending regions narrow or expand in response to a change in SST. The diversity of changes in ascent area is coupled to intermodel differences non-radiative diabatic heating in ascending regions.