This data set consists of a subset of a 1-degree global land cover product (DeFries and Townshend 1994). The subset was created for the study area of the Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA) in South America (i.e., latitude 10° N to 25° S, longitude 30° to 85° W). The data are in ASCII GRID format.
The 1-degree global land cover product (DeFries and Townshend 1994) was compiled by researchers at the Laboratory for Global Remote Sensing Studies (LGRSS) at the University of Maryland. The product was based on Advanced Very High Resolution Radiometer (AVHRR) maximum monthly composites for 1987 of Normalized Difference Vegetation Index (NDVI) values at approximately 8-km resolution, averaged to one-by-one degree resolution. This coarse-resolution data set was used as the basis for a supervised classification of eleven cover types that broadly represent the major biomes of the world. Because of missing values at high latitudes, 1987 Pathfinder AVHRR data for summer monthly NDVI and red reflectance values were used to distinguish the following cover types: tundra, high-latitude deciduous forest and woodland, and coniferous evergreen forest and woodland.
The 1-degree global land cover product is available for download from the Global Land Cover Facility (GLCF)Web site [http://www.landcover.org/. The data are available as a global coverage in both binary and ASCII format. Additional information and references on this data set can be found at the GLCF Web site as well as at the LGRSS Web site (http://www.geog.umd.edu/LGRSS/) and in the readme file for the subset: http://daac.ornl.gov/daacdata/lba/land_use_land_cover_change/land_cover_data_1deg/comp/glcf1deg_readme.pdf.
LBA was a cooperative international research initiative led by Brazil. NASA was a lead sponsor for several experiments. LBA was designed to create the new knowledge needed to understand the climatological, ecological, biogeochemical, and hydrological functioning of Amazonia; the impact of land use change on these functions; and the interactions between Amazonia and the Earth system. More information about LBA can be found at http://www.daac.ornl.gov/LBA/misc_amazon.html.
Cite this data set as follows:
DeFries, R. S., and J. R. G. Townshend. 2003. LBA Regional Land Cover from AVHRR, 1-Degree, 1987 (Defries and Townshend). Data set. Available on-line [http://daac.ornl.gov] from Oak Ridge National Laboratory Distributed Active Archive Center, Oak Ridge, Tennessee, U.S.A. doi:10.3334/ORNLDAAC/677.
DeFries, R. S., and J. R. G. Townshend. 1994. 1 Degree Global Land Cover Data Set Derived from AVHRR. Available on-line [http://www.landcover.org/] from the Global Land Cover Facility, University of Maryland Institute for Advanced Computer Studies, College Park, Maryland, U.S.A.
Information about the ASCII and binary image data formats, land cover classes, and the procedure used to create the LBA subset are in the following file: http://daac.ornl.gov/daacdata/lba/land_use_land_cover_change/land_cover_data_1deg/comp/glcf1deg_readme.pdf.