Data to accompany the article "Radiative Cooling, Latent Heating, and Cloud Ice in the Tropical Upper Troposphere"

Abstract

The radiative cooling rate in the tropical upper troposphere is expected to increase as climate warms. Since the tropics are approximately in radiative-convective equilibrium (RCE), this implies an increase in the convective/latent heating. We examine the impact of these changes on the vertical profile of cloud ice amount in RCE simulations using a cloud-resolving model. Three simulations are conducted: a control run, a warming run, and an experimental run in which there is no warming but the cooling rate is artificially adjusted to mimic a warming scenario. We find that the efficiency of latent heating by cloud ice increases with warming, which tempers the response of the mean cloud ice profile. An analytic expression relating the ice-related latent heating rate to a number of other factors is derived and used to understand the model results. This reveals that the increase in latent heating efficiency with warming is driven mostly by 1) the migration of isotherms to lower pressure and 2) a slight warming of the top of the convecting layer. These physically robust mechanisms curtail the response of the cloud ice profile to global warming.