From the NLCD home page:
“National Land Cover Database 2011 (NLCD 2011) is the most recent
national land cover product created by
the Multi-Resolution Land Characteristics (MRLC) Consortium. NLCD 2011
provides - for the first time - the capability to assess
wall-to-wall, spatially explicit, national land cover changes and trends
across the United States from 2001 to 2011. As with two
previous NLCD land cover products NLCD 2011 keeps the same 16-class land
cover classification scheme that has been applied
consistently across the United States at a spatial resolution of 30
meters. NLCD 2011 is based primarily on a decision-tree
classification of circa 2011 Landsat satellite data.”
“The Multi-Resolution Land Characteristics (MRLC) consortium is a group
of federal agencies who coordinate and generate consistent
and relevant land cover information at the national scale for a wide
variety of environmental, land management, and modeling
applications. The creation of this consortium has resulted in the
mapping of the lower 48 United States, Hawaii, Alaska and
Puerto Rico into a comprehensive land cover product termed, the National
Land Cover Database (NLCD), from decadal Landsat
satellite imagery and other supplementary datasets."
"The primary objective of the MRLC NLCD is to provide the Nation with nationally complete, current, consistent, and public
domain information on the Nation's land cover. Land cover information is critical for local, state, and federal managers and
officials to assist them with issues such as assessing ecosystem status and health, modeling nutrient and pesticide
runoff, understanding spatial patterns of biodiversity, land use planning, deriving landscape pattern metrics, and
developing land management policies."
"All MRLC NLCD data products are available at no charge to the user."
For a detailed definition and discussion on MRLC and
the NLCD 2011 products, please refer to http://www.mrlc.gov/mrlc2k.asp.
The state data sets are provided by NRCS with a 300 meter buffer beyond the state border to facilitate combining the state
files into larger regions.
For seamless CONUS rasters, provided in their native projection (Albers Conical Equal Area)
for all four editions – 1992, 2001, 2006, and 2011, please click here.
For 2001 Alaska, Hawaii and Puerto Rico rasters in their native projections, please click here.
Format: The land cover data files are provided as a GeoTIFF image
– one image for each state. The land cover data sets are single band
raster images.
Spatial Reference Information: Universal Transverse Mercator, North American Datum 1983.
For states with multiple UTM zones, a predominant UTM zone was chosen for the NLCD state map.