Initial results from the Regional Arctic Climate system Model (RACM)

The newly developed Regional Arctic system Climate Model (RACM) is a fully coupled model with atmosphere, ocean, sea ice, and land components. Specific components include the Weather Research and Forecasting (WRF) model as the atmospheric component, the Los Alamos Parallel Ocean Program (POP) at the ocean component, the Los Alamos CICE model as the sea ice component, and the Variable Infiltration Capacity (VIC) model as the land surface component. These four climate system component models are coupled using the NCAR CCSM coupler CPL7.

Initial results from an atmospheric perspective of a series of ten-year (1989-1999) RACM simulations with and without spectral nudging are presented and compared with uncoupled WRF-only simulations. In particular, known circulation biases in WRF-only simulations over polar areas are addressed with respect to the fully-coupled RACM simulations. These simulations will be submitted to the Coordinated Regional Downscaling Experiment (CORDEX) archive as a contribution to the IPCC Fifth Assessment Report.