Compilation of Historical Water Temperature Data for Large Rivers in Alaska using the Landsat Satellite Archive

Water temperature plays a large role in freshwater ecosystems in the Arctic and sub-Arctic. It affects the physical and biological features of rivers, like how the water interacts with the landscape and the life cycles of organisms that live in the river. For example, unseasonably warm water temperatures in Alaska’s large rivers in 2019 caused large numbers of salmon to die before they could reach their spawning grounds. Though water temperature data is important for natural resources monitoring programs, these data are historically lacking and hard to collect for large river systems.  

Satellites and other remote sensing techniques can offer valuable insight to Alaskan stream conditions. They can measure thermal radiation from water surfaces to fill in stream gage data gaps and can cover broader areas than traditional data sets.  

Using Landsat satellite-derived estimates of water temperature, this project will compile historical records of water temperature within the Yukon, Tanana, and Kuskokwim Rivers in Alaska. This work will provide heat maps for the ice-free season between 1985 and present that can be used by natural resource managers to understand important variation in water temperature and to identify favorable habitat conditions for wildlife.