This project will synthesize observational datasets with modeling to improve our understanding and parameterizations of boundary layer clouds over the southeast Pacific Ocean, building on the earlier findings by these researchers from the Eastern Pacific Investigation of Climate Processes in the Coupled Ocean-Atmosphere System (EPIC), a field campaign conducted in 2001 (www.atmos.washington.edu/gcg/EPIC/; www.ofps.ucar.edu/epic/). This and other recent studies suggest drizzle is common, especially in aerosol-poor air masses, and strongly influences cloud properties and boundary layer turbulence. This investigation is to be undertaken using the National Oceanic and Atmospheric Administration's remote sensing cloud data, coupled with surface, radiosonde and buoy data sets. Specific goals are to track cloud evolution within aerosol-poor and aerosol-rich air masses over several diurnal cycles, and to use observations to force and test the National Center for Atmospheric Research's Single-column Community Atmosphere Model.
The work will form the foundation of two doctoral theses, and will also form the central component of the science plan for the VAMOS Ocean Cloud Atmosphere Land Study, an international program within Climate Variability and Predictability. The results are expected to provide an improvement in single-column model parameterizations which will be tested in global Community Atmosphere Model runs.
This project is supported under the Climate Variability and Predictability Program (CLIVAR).