This dataset portrays percent imperviousness surface area for NLCD
mapping superzone thirteen, which covers all of Maine, Vermont, New
Hampshire, Massachusetts, Rhode Island, Connecticut, New York, New
Jersey, Delaware, and Maryland, and parts of Pennsylvania, Virginia,
West Virginia, and North Carolina. Refer to
http://www.mrlc.gov/nlcd_multizone_map.php
for a map of the super-zones.
From NLCD: The National Land Cover Database 2001 was produced
through a cooperative project conducted by the Multi-Resolution Land
Characteristics (MRLC) Consortium. The MRLC Consortium is a
partnership of federal agencies (www.mrlc.gov), consisting of the
U.S. Geological Survey (USGS), the National Oceanic and Atmospheric
Administration (NOAA), the U.S. Environmental Protection Agency
(EPA), the U.S. Department of Agriculture (USDA), the U.S. Forest
Service (USFS), the National Park Service (NPS), the U.S. Fish and
Wildlife Service (FWS), the Bureau of Land Management (BLM) and the
USDA Natural Resources Conservation Service (NRCS). One of the primary
goals of the project is to generate a current, consistent, seamless,
and accurate National Land Cover Database (NLCD) circa 2001 for the
United States at medium spatial resolution. For a detailed definition
and discussion on MRLC and the NLCD 2001 products, refer to Homer et
al. (2003) and http://www.mrlc.gov/mrlc2k.asp.