The land cover analysis was based on data from the Landsat series of satellites, which provide one of the most extensive and continuous terrestrial imagery archives. Since the beginning of the Landsat program in 1972, data have been acquired from three different generations of sensors, the Multispectral Scanner, Thematic Mapper and Enhanced Thematic Mapper Plus data. Landsat imagery of the globe is subset and marketed as a patchwork of individual scenes identified by a row and path designation. Images from Landsat's Thematic Mapper instrument were acquired for 1984 and 1990 and from Landsat's Enhanced Thematic Mapper instrument for 2000. Land surface features were assigned to one of 13 classes, such as commercial, residential, deciduous woodland, cropland, etc. The resulting images can then be processed mathematically to compute land area that has changed from one class to another... Land Cover / Land Use in Madison County, Alabama (3.7MB PDF)
|
