Melt Water Retention Processes in Snow and Firn on Ice Sheets and Glaciers: Observations and Modeling

The percolation, retention, and freezing of melt (and rain) water by snow and firn are a dominant source of uncertainty in surface mass budgets, remain incompletely articulated in the modeling and thus remain critical in understanding ice sheet and glacier mass balance response to climate change. Feedbacks between atmospheric parameters, surface and sub-surface properties are crucial in characterizing the water retained and that transmitted. Understanding the controlling factors of water percolation is fundamental to simulate water retention and runoff through snow and firn, while the relative importance of rain and melt intensity and duration at the surface seem key in understanding changes in percolation fluxes. In past and future climate change scenarios, understanding what fraction of melt and rain water is trapped by snow and in firn layers and what fraction runs off remains at the science frontier.
We encourage authors to submit original work and review articles to improve knowledge on observing and modelling water retention processes in snow and firn on ice sheets and glaciers. Potential contributions could include, but are not limited to:
• parameters affecting water retention in snow and firn
• key measurement and techniques
• observation and model uncertainties
• how well we model the current and historical surface mass balance evolution on both glaciers and ice sheets