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Southern Hemisphere Snow Cover Extent

As part of its monthly State of the Climate Global Snow & Ice report, the National Climatic Data Center monitors monthly and seasonal snow cover extent across the Northern Hemisphere's major land areas — North America and Eurasia — using data from the Rutgers Global Snow Lab. Snow cover extent is sensitive to both regional temperatures and precipitation patterns across the mid and high latitudes, providing an important metric to measure the earth's climate system. By utilizing NOAA satellites, snow cover can be observed over all land areas, not just locations with surface-based observations, which can be sparse in non-developed areas of the globe.

Snow cover extent in the Southern Hemisphere is not currently examined for several reasons:

  • Snow cover can only be measured over land areas, and not the ocean surface. Most of the surface area of the Southern Hemisphere is covered by ocean.
  • The Southern Hemisphere land area located in the mid and high latitudes is very small, excluding Antarctica, when compared to the land area of the Northern Hemisphere at the same latitudes.
  • The Antarctic continent is generally snow covered year round, with very little annual variation.
  • Snow cover is difficult to measure across Antarctica and the high elevations of South America. These land areas are mostly covered by glaciers, and it is nearly impossible to distinguish snow cover from glacial ice using current satellite technology.