Please note that this session was withdrawn and is no longer available in the respective programme. This withdrawal might have been the result of a merge with another session.
CR5.4 | Rain-on-snow
EDI
Rain-on-snow
Convener: Leena Leppänen | Co-conveners: Melody Sandells, Mathias Bavay, Elmer Topp-Jørgensen, Bartłomiej Luks
Rain-on-snow (ROS) events, when rain falls on existing snow cover, rapidly alter snow properties by increasing density and liquid water content, changing snow microstructure and by forming hard ice layers. In northern regions, ROS events hinder herbivores such as reindeer from accessing forage, while in hydrological systems they can trigger rapid runoff and flooding. As climate warming drives more frequent and intense ROS events, their ecological, hydrological, and socio-economic impacts are expected to increase.

This session invites contributions that improve understanding of ROS processes and their consequences through measurements, modelling, and remote sensing. Topics include, but are not limited to:
- Field observations of ROS processes
- Advances in snow modelling and hydrological modelling under ROS conditions
- Remote sensing of ROS effects, including microwave emission and albedo changes
- Microstructural processes in ROS conditions
- Rapid snowmelt-events
- Distribution of liquid water content
- Spatial variability of ice layers
- Impacts on runoff, flooding, and other related natural hazards
- Ecological impacts of ROS
- Assessments of consequences for northern ecosystems

By connecting expertise across cryospheric science, hydrology, and remote sensing, this session aims to foster an integrated view of ROS events and their implications in a changing climate.