Final Report on Evaluating the Representation and Impact of Convective Processes in the NCAR Community Climate System Model
Convection and clouds affect atmospheric temperature, moisture and wind fields through the heat of condensation and evaporation and through redistributions of heat, moisture and momentum. Individual clouds have a spatial scale of less than 10 km, much smaller than the grid size of several hundred kilometers used in climate models. Therefore the effects of clouds must be approximated in terms of variables that the model can resolve. Deriving such formulations for convection and clouds has been a major challenge for the climate modeling community due to the lack of observations of cloud and microphysical properties. The objective of our DOE CCPP project is to evaluate and improve the representation of convection schemes developed by PIs in the NCAR (National Center for Atmospheric Research) Community Climate System Model (CCSM) and study its impact on global climate simulations. • The project resulted in nine peer-reviewed publications and numerous scientific presentations that directly address the CCPP’s scientific objective of improving climate models. • We developed a package of improved convection parameterization that includes improved closure, trigger condition for convection, and comprehensive treatment of convective momentum transport. • We implemented the new convection parameterization package into several versions of the NCAR models (both coupled and uncoupled). This has led to 1) Improved simulation of seasonal migration of ITCZ; 2) Improved shortwave cloud radiative forcing response to El Niño in CAM3; 3) Improved MJO simulation in both uncoupled and coupled model; and 4) Improved simulation of ENSO in coupled model. • Using the dynamic core of CCM3, we isolated the dynamic effects of convective momentum transport. • We implemented mosaic treatment of subgrid-scale cloud-radiation interaction in CCM3.
- Research Organization:
- Univ. of California, San Diego, CA (United States)
- Sponsoring Organization:
- USDOE - Office of Energy Research (ER)
- DOE Contract Number:
- FG02-04ER63865
- OSTI ID:
- 927421
- Report Number(s):
- DOEER63865- Final Report
- Country of Publication:
- United States
- Language:
- English
Similar Records
Evaluating the Representation and Impact of Convective Processes in the NCAR’s Community Climate System Model
2014-2018 Summary of NCAR activities in the Earth Energy Exascale System Model (E3SM) project