A Simple Method to Evolve Daily Ground Temperatures from Surface Air Temperatures in Snow-Dominated Regions

Abstract

A simple model is developed to evolve daily ground temperatures from surface air temperatures (SATs) in snow-dominated areas. Ground surface temperatures (GSTs) are calculated by propagating the daily SAT through the snowpack, and attenuating the signal amplitude. Subsequent subsurface heat transfer is then modeled using the analytical solution of the one-dimensional heat conduction equation. The thermal impacts of nonconductive heat transfer processes and seasonal freeze thaw are implicitly represented by the time-dependent apparent thermal diffusivity of the subsurface. The model is tested in four snow-dominated regions: Barrow, Council, Ivotuk (all in Alaska) and Reynolds Creek Experimental Watershed (in Idaho). The model captures the seasonal evolution of the ground temperature at all sites. The model demonstrates the feasibility of simulating subsurface temperatures using only air temperature and snow depth.