The presence of snow as a land or ice cover completely changes the interaction with the atmosphere as opposed to snow-free surfaces. At the same time, water stored in the snow pack represents an important component of the hydrological balance in many regions of the world and snow is the source of most ice masses. Monitoring and modeling of snow accumulation and melt is often particularly difficult because of limited availability and large spatial variability of hydrological and weather data. The objective of this session is to integrate specialists focusing on snow within the context of catchment hydrology, snow as a land surface, snow-vegetation interaction and snow as a source for glacier ice. The aim is to integrate and share the knowledge and experience in the fields of experimental research, remote sensing and modeling.

Specifically, contributions addressing the following topics are welcome:
- results of experimental research on snow properties and processes and their potential for an implementation in hydrologic catchment, glacier and land-surface models;
- experimental research and innovative modelling approaches addressing the effect of vegetation on snow energetics, properties and distribution;
- evaluation of different remote sensing technologies and classification approaches focusing e.g. on snow cover, albedo, snow depth and snow water equivalent mapping;
- snow data assimilation for different models;
- practical implementation of snow data in operational hydrological and weather forecast modeling.


The main objectives of the Sub-arctic hydrology part include:
Understanding climate change in boreal and sub-Arctic regions of the Northern Hemisphere is crucial to managing consequences of a changing hydrological environment, including the repercussions for biogeochemical cycling (e.g. exports of C, N, P and metals). Being able to predict variations in the regional patterns of precipitation, storage (both subterranean and as snow/ice packs) and both timing and quantity of release of water into the river channels is of significant importance to land managers, local authorities, industry and researchers alike. We solicit contributions that study boreal and sub-arctic hydrological systems and the impacts of changes to them through e.g., field observations, environmental and water resources monitoring and its challenges, water-land-atmosphere modelling, and hydrological processes as well as tracer studies at different space-time aggregation scales that contribute to the advancement of hydrological understanding in this environment. We especially emphasize inter-catchment comparison studies and hydrology-energy balance-interaction studies that will improve our understanding of the sensitivity, resilience and functioning of sub-arctic catchments to climate change and human impacts.