Presentation #543.03 in the session “Extrasolar Planets: Atmospheres”.
Clouds substantially impact the climate and atmospheric structure of worlds throughout our solar system, from giant planets like Jupiter to smaller bodies such as Earth, Venus, Mars, and Titan. Furthermore, a critical feature of habitable planets, like our Earth, is that a substantial fraction of their visible disk is obscured by clouds. Thus, not only do aerosols play a key role in the radiative balance of nearly all solar system planets, but clouds are also expected to significantly sculpt the spectral appearance of many (if not all) Earth-like exoplanets. One-dimensional planetary atmosphere models offer a powerful and computationally efficient approach to exploring a broad range of planetary and atmospheric conditions. Unfortunately, many such one-dimensional models lack a physical treatment of clouds. For example, the CLIMA model (Kasting 1988; Kopparapu et al. 2013) – which is one of the most commonly applied one-dimensional terrestrial atmospheric radiative-convective equilibrium models – lacks a realistic treatment of water vapor and carbon dioxide clouds. To improve this model, and to broaden its range of applicability, we have incorporated a well-known one-dimensional cloud model (Ackerman and Marley 2001) via a two-column (clear versus clouded) treatment of the atmosphere (Marley et al. 2010).
The well-known atmospheric properties of Earth are an excellent test case for this newly developed atmospheric model. For each of these simulations, we generate an equilibrium radiative-convective atmospheric structure and vary the fractional clear sky column in each climate model in order to fine tune the effective cloudiness of our Earth model. In light of this we have reproduced condensate mixing ratio profiles, temperature-pressure profiles, and cloud optical properties from our dynamic model that are in good agreement with real Earth observations.