Effects of Cloud and Radiation Processes on the Global Water and Energy Cycle

Iowa State University, Ames IA

Investigators

Abstract

Cloud, radiation and precipitation processes are key components of the global water and energy cycle and operate on a wide range of time and space scales. Uncertainties in representing these processes and inadequate understanding of water and energy cycle have been long standing problems for most general circulation models (GCMs). This project aims to investigate the role of cloud, radiation and precipitation processes in the improved climate simulations of global water and energy cycle. The investigator will (a) evaluate modeled dynamic and thermodynamic fields against observations in diurnal and seasonal aspects of temperature, water vapor, cloud amount, liquid and ice water, radiative fluxes, precipitation and surface evaporation, (b) examine the impacts of revised convection closure assumption, triggering mechanism, convective momentum transport and subgrid cloud distribution on the simulations of climate mean state and variability, and (c) assess the water vapor budget and the top of the atmosphere and surface energy budgets during the El Niño and La Niña events in comparison with those under the normal climate conditions. Broader impacts of this work are educational and in improving understanding of physical processes for water and energy cycle in the climate system and representations of cloud and radiation processes in GCMs, which will enhance the credibility of climate prediction and climate change projections made by GCMs and thus benefit society.