Aerosol – cloud – rainfall interactions are complicated yet important since changes in rainfall can adversely impact human societies. Though the NASA “A-train” has provided a remarkable set of coordinated satellite experiments by which these interactions can be studied, the interactions are not easy to quantify since the physics is intricate and the retrievals of aerosol fields in the vicinity of clouds are difficult. This presentation illustrates the complicated physics by discussing one of the many aerosol-cloud interactions, i.e. how changes in aerosol optical depths produce changes in cloud vertical structure. We demonstrate that absorptive aerosols inhibit the development of deep convective clouds. We also demonstrate that “cloud adjacency” effects (i.e. radiances and retrieved aerosol fields are perturbed in the vicinity of clouds) complicate the aerosol-cloud calculations. Finally, the cloud adjacency issue is discussed in relation to forthcoming measurements of CO2 by the Orbiting Carbon Observatory.
Published on May 24, 2013
Speaker:Steve Massie (NCAR)