Snowmelt and rain-on-snow (ROS) events enhance the liquid water content of a snowpack, which affects snow properties such as depth, density, grain size, and extent. These changes are associated with transfers of latent and sensible heat and create a positive feedback that accelerates snowmelt processes.
Snow wetness and icing can affect ecosystem processes at multiple spatial and temporal scales including hydrology, carbon cycling, wildlife movement, and human transportation. Snow wetness occurs when the cold content of part or all of the snowpack is less than the positive energy fluxes from radiative, sensible, or latent heat transfer. Icing events normally occur daily in the spring and summer and less predictably following wintertime rain on snow or warm weather.