CR4.5/NH8.6Risks from a changing cryosphere (co-organized)
|Convener: Christian Huggel | Co-Conveners: Jeffrey Kargel , Katherine Barnhart|
All components of the cryosphere have been undergoing significant changes. Most visibly, glaciers are retreating and thinning. Snow cover and duration is generally reduced, and permafrost, in both Arctic and alpine environments, is thawing. Changes in sea ice cover and characteristics have attracted widespread attention, and changes in ice sheets are monitored with care and concern.
Risks associated with one or several of these cryosphere components have been present throughout history. However, as well documented surface warming continues, we expect the magnitude and rate of change of hazards currently observed and projected for the future to change with profound implications for risks. New or growing glacier lakes pose a threat to downstream communities through the potential for sudden drainage. Thawing permafrost can destabilize mountain flanks, and eventually result in destructive rock and ice avalanches. An accelerated rate of permafrost degradation in low-land areas poses risk to existing and planned infrastructure and raises concerns about large-scale emission of greenhouse gases currently trapped in Arctic permafrost. Decreased summertime sea ice extent may produce both risks and opportunities in terms of large-scale climate feedbacks and alterations, coastal vulnerability, and new access to transport routes and natural resources. Eventually, rapid acceleration of outlet glacier ice discharge and collapse of ice sheets is of major concern for sea level change.
This session invites contributions across all cryosphere components that addresses risks associated with observed or projected physical processes. Contributions considering more than one cryosphere component (e.g. glaciers and permafrost) are particularly encouraged. Contributions can consider hazards and risks related to changes in the past, present or future. Discussion of both new risks and opportunities are encouraged, as long as a critical analysis is provided.