This data set is a subset of Hansen et al. (1999), "1 km Global Land Cover Data Set Derived from AVHRR," which was developed at the Laboratory for Global Remote Sensing Studies (LGRSS) at the University of Maryland. 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.
In recent years, researchers have increasingly turned to remotely sensed data to improve the accuracy of data sets that describe the geographic distribution of land cover at regional and global scales. 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, LGRSS researchers have employed the NASA/NOAA Pathfinder AVHRR Land (PAL) data set with a spatial resolution of 1 km. The PAL data set has a record length of 14 years (1981-1994), providing the ability to test the stability of classification algorithms. The PAL 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 LGRSS researchers' 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 1-km global land cover product was created from 1992-1993 local area coverage (LAC) AVHRR data. The global land cover product is available for download from the University of Maryland's Global Land Cover Facility (GLCF) Web site (http://glcf.umiacs.umd.edu/data/landcover/index.shtml). Forty-one metrics were developed to describe global vegetation phenology, and these data were used to make the 1-km land cover map. The final product contains 13 land cover classes.
More information can be found at http://daac.ornl.gov/daacdata/lba/land_use_land_cover_change/land_cover_data_1km/comp/glcf1km_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:
Hansen, M. C., R. S. DeFries, J. R. G. Townshend, and R. Sohlberg. 2003. LBA Regional Land Cover from AVHRR, 1-km, 1992-1993 (Hansen 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/678.
Hansen, M. C., R. S. DeFries, J. R. G. Townshend, and R. Sohlberg. 1999. 1 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 ASCII data and binary image file 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_1km/comp/glcf1km_readme.pdf.