Recent advances and challenges in satellite-based snowfall detection and estimation

The use of satellites for snowfall continuous monitoring and quantification on a global scale is fundamental to quantify water resources, and for understanding feedback mechanisms and interconnections in hydrology and climate. Spaceborne active and passive microwave sensors are particularly tailored to provide consistent measurements of falling snow thanks to their ability to penetrate clouds. However, remote sensing of snowfall remains among the most challenging tasks in precipitation science. Indeed, current state-of-the-art satellite products show large discrepancies in snowfall climatologies. The goal of this chapter is to provide an overview of the most recent studies dedicated to satellite-based snowfall detection and quantification by highlighting, in particular: (1) potentials and limitations of the most advanced spaceborne microwave sensors used for snowfall observation; (2) the main issues and challenges encountered in satellite-based retrieval of falling snow; and (3) recent advancements made in the scientific community in the attempt to overcome some of these issues. Concluding remarks include recommendations on future observation and retrieval strategies to improve detection and quantification of falling snow, with particular focus on higher latitudes.