Snow Across the Plains
March 29, 2002
Snow cover left in the wake of a snow storm that swept across the Great Plains on 14-15 March 2002 is seen on this false color image (left) from the MODIS instrument on board the Terra satellite, acquired 16 March 2002 and on the snow map produced from the MODIS snow algorithm (right). The MODIS instrument is especially useful for mapping and monitoring snow since it operates in those channels of the visible spectrum most sensitive to snow, and because it's capable of differentiating between clouds and snow on the ground. MODIS has a resolution ranging from 250 m to 1 km (775 feet to 0.6 miles).
The greatest amounts of snow fell in a band from southwestern South Dakota to Minnesota. A snow depth of about 40 cm (16 inches) was reported at Pine Ridge, SD and about 27 cm (11 inches) at Minneapolis. Appearance of the snow cover (yellow) on the false color MODIS image changes with the landscape, from the plains to the forests and lakes regions west of Lake Superior. Snow extent is shown in white on the snow map - clouds are not shown.
MODIS data were obtained from the direct broadcast facility at the Space Science and Engineering Center, University of Wisconsin. The snow map was produced at Goddard Space Flight Center.