Rain on Snow and Extreme Precipitation Events across the Arctic and their Impacts on Social-Ecological Systems

Rain on Snow (ROS) and extreme precipitation events have significant impacts on Arctic wildlife, livestock, and the communities that depend on these resources for subsistence. The icy crusts that form after ROS events and deep snow can interfere with travel and searching for food. ROS events have been linked to massive die-offs of reindeer and caribou. Polar bear and ringed seal populations are also affected--rains early in the breeding season destroy dens built under the snow and increase cub/pup mortality. The purpose of this study is to better understand the frequency and cause of ROS and extreme precipitation events across the Arctic, how their frequency and severity are changing as the Arctic warms, and their social-ecological impacts. With a primary focus on hunting and reindeer herding livelihoods, this study involves close collaborations with Indigenous hunters and herders.

ROS and extreme precipitation events will be detected using various types of satellite data, weather data from atmospheric re-analyses, and surface observations. Indigenous hunters and herders will be engaged through extensive local observing, interviews, group discussions, and participatory workshops to validate the detection algorithms, and to assess effects of ROS and extreme precipitation events on wildlife and community activities. Similarly, the project will partner with reindeer herders to better understand implications for modern tundra reindeer nomadism and mortality episodes significant enough to have entered the oral record. Expert systems models will be developed to assess how ROS and extreme precipitation events impact wildlife, migratory reindeer herding, hunting, and other community activities in terms of event timing, geographic scale, snow/land cover, and existing community practices. A Data and Knowledge Hub, serving as the project website and a resource on the state of knowledge regarding Arctic ROS and extreme precipitation events and their impacts, will become the project's extension to the US Arctic Observing Network. The project also closely connects with the NSF ELOKA (Exchange for Local Observations and Knowledge of the Arctic) project, and long-time/on-going research collaboration with Inuit hunters, communities across Northern Alaska, and applied community-based ecological research in Lapland and Russia.