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Land Use and Land Cover Digital Data

Land Use and Land Cover Digital Data

 

Land Use and Land Cover Digital Data

Overview

General description

Land use and land cover (LULC data are derived from thematic overlays registered to 1:250,000-scale base maps and a limited number of 1:100,000-scale base maps. Land use and land cover data provides information on urban or built up land, agricultural land, range land, forest land, water, wetlands, barren land, tundra, and perennial snow or ice. Associated maps display information in five data categories: (1) political units, (2) hydrologic units, (3) census county subdivisions, (4) Federal land ownership, and (5) State land ownership.

Geographic coverage

National

LULC data is available for the conterminous United States and Hawaii. Refer to the LULC National Index sheet, available free of charge upon request. Digital data registered to the United States Geological Survey (USGS), 1- by 2-degree, 1:250,000-scale base maps; and a limited number of USGS 30- by 60-minute, 1:100,000-scale base maps are available.

Who collects it

How often

What is in it generally

The 1:100,000- and 1:250,000-scale LULC and associated maps used to produce the digital files are polygon, or area, maps. Areas consisting of uniform structures and similar characteristics are compiled on the map as a series of lines forming a polygons. Each polygon is identified with an attribute code, derived from a modified Anderson level II scheme, describing the area. Digitized map information is processed through the Geographic Information Retrieval and Analysis System to produce data in two formats: the vector polygon and the composit grid cell formats.

In the vector polygon format, all topological elements of the polygon map are represented as points, lines, and areas that (with special software) may be joined to form polygons replicating the graphic map.

In the composite grid cell format, the map is divided into 4-hectare (10-acre) cells. Each cell is completely identified with attribute codes for all LULC and associated map data.

Digital LULC and associated maps are stored in the UTM coodinate system.

How to access

9-track magnetic tapes. The 1:250,000-scale data and the 1:100,000-scale data is available online.

Contact any Earth Science Information Center for additional information or to place an order.

Data Dictionary

http://nsdi.usgs.gov/nsdi/products/lulc.html


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