Snow Cover—Observations, Processes, Changes, and Impacts on Northern Hydrology

Abstract

This chapter presents an overview of Arctic terrestrial snow cover and hydrology starting with the factors contributing to variability and change in large-scale snow cover extent and snow water equivalent (SWE), then moves to the local scale for a discussion of the processes and interactions responsible for the spatial distribution and physical properties of Arctic snow cover, most notably the roles of blowing snow and vegetation interactions. Snowmelt and runoff processes are subsequently covered with particular attention on liquid water infiltration through the snowpack and soil layers. The chapter concludes with an overview of Arctic snow observing systems, estimates of current and projected trends in Arctic snow cover extent and SWE, and potential hydrologic implications of the projected changes in snow cover. A key message from the Chapter is that the response of Arctic snow cover and snow hydrology to a changing climate is complex due to the numerous linkages and feedbacks within the coupled snow–soil–vegetation system.