Analysis of Large Lake Temperature Trends Across North America Using Satellite Data: A Contribution to the National Climate Assessment

Large lakes are recognized as an indicator of climate change by the United States National Climate Assessment (NCA). Understanding how large inland water bodies will respond to climate change will improve our ability to manage vital natural resources such as water quantity, water quality, and ecological entities dependent upon freshwater resources. Studies have targeted impacts on specific species, but our objectives focus on establishing a better understanding of how the ecological environment of inland water bodies may change in the future. In this study we present analysis of temperature trends for 268 large lakes that span Central and North America derived from thermal infrared data of various satellites (MODIS, ATSR, and VIIRS) with 1km resolution from 2000 – 2014. Although satellite measurements measure surface temperature dynamics, they serve to compliment in-situ observations of water temperature profiles. Satellites provide long-term, frequent spaceborne information about water bodies, including those that do not have in-situ monitoring. Our analysis shows that the majority of lakes are displaying warming trends that are surpassing trends of ambient air temperature. These findings are essential for analysis of future sustainability of large lake fisheries, water resource managers, policy makers, and the general public.