Modeling Arctic Climate with a Regional Arctic System Model (RASM)

A new regional Earth system model of the Arctic, the Regional Arctic System Model (RASM), has recently been developed. The initial version of this model includes atmosphere (WRF), ocean (POP), sea ice (CICE), and land (VIC) component models coupled with the NCAR CESM CPL7 coupler. A newer version of the model that adds a Greenland ice sheet model (CISM), mountain glacier model, and carbon-nitrogen and dynamic vegetation components to the land model is currently being developed. The model is configured to run on a large pan-Arctic domain that includes all sea ice covered waters in the Northern Hemisphere and all Arctic Ocean draining land areas. Results from multi-decadal (1989 to present) simulations with RASM will be presented and will focus on the model's representation of atmosphere, ocean, sea ice, and land surface climate, emphasizing both strengths and weaknesses of the current model climate. Problems encountered and lessons learned during the development of RASM will be discussed. The presentation will conclude with future plans for RASM.