Accurately quantifying energy and water balance in complex terrains require careful consideration of the interplay of steep topography, spatial heterogeneity in land characteristics, and microclimatic variability. Earth system models typically operate at resolutions of hundreds of kilometers and lack the details to capture hillslope processes and topography-driven feedback crucial for assessing regional-scale hydrology, ecology, and hydroclimates.
This work aims to improve the representation of snow processes in mountainous regions using the Hillslope Hydrology configuration of the Community Terrestrial Systems Model (CTSM; the land component of the Community Earth System Model CESM) that accounts for terrain characteristics (aspect, relief, and slope). Topography profoundly influences snowpack dynamics by modifying the absorption and reflectance of incoming solar radiation, gradients of temperature and precipitation with elevation, and redistribution of snowfall due to wind. By explicitly modeling these processes, the CTSM Hillslope Hydrology configuration can significantly improve estimates of snowpack evolution, seasonal and sub-seasonal streamflow, and the terrestrial energy and water budgets in topographically complex domains.