Abstract: The Circum-Arctic permafrost and ground ice map is available via ftp in ESRI Shapefile format and Equal-Area Scalable Earth Grid (EASE-Grid) format. See the Format section for an explanation of the files provided via ftp. The circumpolar permafrost and ground ice data contribute to a unified international data set that depicts the distribution and properties of permafrost and ground ice in the Northern Hemisphere (20°N to 90°N). The re-gridded data set shows discontinuous, sporadic, or isolated permafrost boundaries. Permafrost extent is estimated in percent area (90-100%, 50-90%, 10-50%, <10%, and no permafrost). Relative abundance of ground ice in the upper 20 m is estimated in percent volume (>20%, 10-20%, <10%, and 0%). The data set also contains the location of subsea and relict permafrost. the gridded data are gridded at 12.5 km, 25 km, and 0.5 degree resolution. The shapefiles were derived from the original 1:10,000,000 paper map (Brown et al. 1997) Permafrost, or permanently frozen ground, is ground (soil, sediment, or rock) that remains at or below 0°C for at least two years (Permafrost Subcommittee, 1988). It occurs both on land and beneath offshore arctic continental shelves, and underlies about 22% of the Earth's land surface. For more information on the creation of the original map, see Heginbottom et al. (1993). The original paper map also includes information on the relative abundance of ice wedges, massive ice bodies and Pingos, ranges of permafrost temperature and thickness (Brown et al. 1997).

Purpose: scientific research

Publication Date: 20020201

Originator: Brown, J., O.J. Ferrians, Jr., J.A. Heginbottom, and E.S. Melnikov.

Online citation: \\KODIAK\I$\ProjectData\USFWS_CGL\CGL_LG_Data.mdb

Bounding coordinates:
West: -168.092182
East: -129.177327
North: 69.077973
South: 58.626998

Place Keywords: Geographic Region > Polar > Circumpolar

Theme Keywords: EARTH SCIENCE > Cryosphere > Frozen Ground > Ground Ice, EARTH SCIENCE > Cryosphere > Frozen Ground > Permafrost, EARTH SCIENCE > Land Surface > Frozen Ground > Ground Ice, EARTH SCIENCE > Land Surface > Frozen Ground > Permafrost, geoscientificinformation, imageryBaseMapsEarthCover, Boreholes, Continuous Permafrost, Discontinuous Permafrost, Mapping, Permafrost Extent

Geographic: GCS_North_American_1983

Attributes of: Permafrost_Regions

Metadata date: 20090722