Developing Parameterizations of Cloud Microphysics to Cross Scales from Cloud Chambers to Earth System Models

Improving the ability of climate models to simulate future changes will require breakthroughs in representing several poorly constrained cloud and aerosol processes, including droplet collision-coalescence rates, ice nucleation, scavenging in mixed-phase clouds, and the in-cloud chemical processing of atmospheric aerosols. These complex processes are fundamentally difficult to measure in the free atmosphere and in current cloud chambers. DOE is planning a new laboratory facility to study these and other important atmospheric processes under representative yet controlled, reproducible, and sustained cloud conditions to improve large-scale simulations of weather and climate. This work describes the development of multi-scale models of cloud microphysics to enable the use of a proposed cloud chamber for direct application to large scale Earth System Models. We outline a series of modeling exercises demonstrating our ability to utilize cloud chamber observational results to improve the representation of cloud microphysical processes in climate models, from DNS experiments, to LES and multi-scale global models, thereby demonstrating a pathway for knowledge gained from chamber process studies to impact climate models.