This data set is a subset of an 8-km global land cover product (DeFries et al. 1998). This 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 file format.
To develop improved methodologies for global land cover classifications as well as to provide global land cover products for immediate use in global change research, researchers at the Laboratory for Global Remote Sensing Studies at the University of Maryland employed the NASA/NOAA Pathfinder AVHRR Land (PAL) data set with a spatial resolution of 8 km. The PAL data set has a length of record of 14 years (1981-1994), providing the ability to test the stability of classification algorithms. Furthermore, the data set includes red, infrared, and thermal bands in addition to the Normalized Difference Vegetation Index (NDVI). Inclusion of these additional bands improves discrimination between cover types. The project's aim was to develop and validate global land cover data sets and to develop advanced methodologies for more realistically describing the vegetative land surface based on satellite data.
The global land cover product (Defries et al. 1998) was derived by testing several metrics that describe the temporal dynamics of vegetation over an annual cycle. These metrics were applied to 1984 PAL data at 8-km resolution to derive a global landcover classification product using a decision tree classifier. The final product contains 13 land cover classes. The original 8-km global land cover product is available for download from the University of Maryland's Global Land Cover Facility (GLCF) Web site (http://glcf.umd.edu/data/landcover/). 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/landcover/global-cover.html).
More information can be found at http://daac.ornl.gov/daacdata/lba/land_use_land_cover_change/comp/land_cover_data_8km/glcf8km_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.
Cite this data set as follows:
DeFries, R. S., M. Hansen, J. R. G. Townshend, and R. Sohlberg. 2003. LBA Regional Land Cover from AVHRR, 8-km, 1984 (DeFries et al.). 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/680.
DeFries, R. S., M. Hansen, J. R. G. Townshend, and R. Sohlberg. 1998. 8 km Global Land Cover Data Set Derived from AVHRR. Global Land Cover Facility, University of Maryland Institute for Advanced Computer Studies, College Park, Maryland, U.S.A.
Information about the data format, 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_8km/comp/glcf8km_readme.pdf.
2003/9/8
2003/9/8
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