Assessing the Impacts of Falling Ice Radiative Effects on the Seasonal Variation of Land Surface Properties

Abstract An accurate representation of clouds, precipitating clouds, and their radiative impacts on the land-atmosphere feedback processes has strong implications for the reliability of projected land surface properties and their variability inferred by global climate models (GCMs). This study explores the linkage of surface energy balance, land surface temperature (LST) and land surface properties with falling ice (snow) radiative effects (FIREs) using CESM1-CAM5 sensitivity experiments with FIREs-off (NOS) and on (SON) under CMIP5 historical run. This linkage is inferred by examining the changes of spatial distribution and seasonal cycle of surface radiation, LST and land surface properties. For boreal winter, NOS relative to SON, simulates less surface downward longwave and net flux (∼2–15 Wm-2), resulting in colder LST (∼2–4 K) and cooler surface air temperatures over mid- and high-latitudes, which is associated with a shift in soil moisture state from liquid to frozen, increases snow cover and a delay in snowmelt and thawing of soil ice until summer, consequently suppressing vegetation productivity in the following seasons.