09 December 2016

Land Surface Climate in the Regional Arctic System Model

Development and evaluation of the RASM Land Surface Scheme

Science

This work introduces a new land surface scheme as part of the Regional Arctic System Model (RASM) and presents the baseline evaluation of the dominant terrestrial processes at play in the Arctic climate system. This study is intended to lay the groundwork for future model application and development of RASM.

Impact

This work introduced a novel coupling of the Variable Infiltration Capacity (VIC) model within a coupled Earth System Model. In the process of evaluating the VIC mode, we identified areas where both RASM and global renalyses could be improved, namely in the simulation of turbulent heat fluxes and runoff generation.

Summary

This work presents the baseline land-surface climate in the recently developed Regional Arctic System Model (RASM). The primary goal of this study was to identify areas where the RASM land surface scheme is performing well and areas for future development. This work used the fully-coupled Regional Arctic System Model (RASM) and evaluated the performance of the land surface scheme (the Variable Infiltration Capacity [VIC] model) relative to a range of observation, remote sensing and model based datasets. The performance of the model was assessed based on RASM’s ability to represent the first order behavior of Arctic land surface processes such as the seasonal cycle of snow, the differences between the tundra and taiga in terms of turbulent heat fluxes, and the partitioning of precipitation into evaporation and runoff. Recommendations for further model development related to atmosphere-canopy interactions and frozen soils were presented.

Contact
Bart Nijssen
University of Washington
Publications
Hamman, J, B Nijssen, J Cassano, A Craig, A DuVivier, M Hughes, DP Lettenmaier, et al.  2016.  "Land Surface Climate in the Regional Arctic System Model."  Journal of Climate 29(18): 6543-6562.  https://doi.org/10.1175/JCLI-D-15-0415.1.