Circumpolar Arctic Lake Cover Map
Percent lake cover strongly affects the albedo, or reflectance, of the land surface over large areas of the Arctic, and is useful for delineating extensive wetlands. Initially lake cover was derived from the AVHRR imagery in several different ways, producing maps that were used to help define vegetation polygons. For Russia, the Map of the World hydrology cover was converted to lake polygons, and then a grid cell analysis (20 x 20 km cell size) was used to calculate percent lake cover. For Canada, a similar procedure was used, with a 7.5 x 7.5 km cell size. For Alaska, visual estimates from 1:63,360 topography maps were used to classify percent lakes. For Greenland, visual estimates of percent lakes were made based on the AVHRR false-CIR imagery, as well as from topography maps.The final percent lake cover map was calculated as the number of AVHRR water pixels in each mapped CAVM polygon, divided by the total number of pixels in the polygon. Since the imagery has a pixel size of 1 km2, lake cover is underestimated for areas with many small lakes. No pixels were sampled within 2 pixels (2 km) of the coastline to avoid including ocean pixels.
Data and Resources
Download :: GIS Data
aga_circumpolar_lake_cover_2003_shp.zip (2.34 MB)
Website :: Toolik Arctic Geobotanical Atlas