Ice Cover in Lake-Climate Interactions at High Latitudes
(Sponsor: Natural Sciences and Engineering Research Council of Canada)
Lakes are sensitive indicators of climate variability and change. They also play an important role in the energy and water balance at local and regional scales, influencing climate and weather. Lake-effect snow, for example, is a well-documented phenomenon for the Great Lakes region of Ontario and U.S. However, little is known about the role of large lakes or the combined effect of smaller water bodies in lake-rich areas found at high latitudes on climate and weather. Also, much remains to be learned about the response of lakes of various sizes to recently documented and projected Arctic climate warming. One of the key variables that is sensitive to climate conditions and that influences lake-atmosphere interactions in these cold environments is ice cover. Its presence/absence and thickness have an impact on energy/heat exchanges with the overlying atmosphere. Yet, the magnitude of these exchanges is poorly documented and quantified.
We are developing and improving state-of-the-art remote sensing algorithms and numerical lake models to: 1) document and elucidate the contemporary response of Arctic lake ice cover to climate, and establish linkages with other components of the Arctic system; 2) determine what changes can be expected in lake ice cover conditions across the Arctic until the end of the 21st century; and 3) determine and quantify the role of lake ice cover on Arctic weather and climate. Changes in ice conditions with climate warming are anticipated to have an important feedback effect on energy, water and biogeochemical cycling, and significant impacts on the biological productivity of aquatic systems. Such changes will have a significant influence on food availability/quality (i.e. fish) for Arctic communities. A reduction in ice cover season and ice thickness will also create problems of accessibility to food by reducing the reliability of traditional hunting ice-based routes and safety of ice-based travel. This research is making a significant societal contribution by generating new data and information on the state of lake ice conditions in a warming Arctic climate.