SATELLITE IMAGING OF NATIONAL PARKLANDS IN THE ARID SOUTHWEST

The national parks, monuments and recreation areas in the American Southwest afford a unique opportunity to promote public understanding of, and appreciation for, land surface processes and landscape change in arid and semiarid environments. The readily accessible, highly visible (and often spectacular) landscapes of these parklands have been developed under the influence of a broad range of neotectonic, structural, lithologic, biologic and climatic conditions. The constituent landforms and landform associations that comprise these landscapes provide numerous clear and compelling examples of the active role played by earth surface processes in arid and semiarid lands.

In order to promote a better understanding of landscape development and evolution in arid lands, a series of full-color satellite image maps is being developed for the national parklands of the American southwest. These maps are produced from Landsat 7 satellite data (spectral bands 1, 2,3, 4, and 7). These data are converted to, and specially enhanced in, HSI color space to produce intuitive images wherein vegetation is shown in various shades of green and yellowish green and water is shown in various shades of blue. Where vegetation is sparse, surficial deposits and exposed bedrock appear in a variety of colors that reflect subtle differences in mineralogical composition. These maps provide unique synoptic views of geologic and biologic features. They constitute an ideal intermediate-scale base for the mapping and analysis of bedrock, surficial deposits, and vegetation; and they can be used to support interpretative programs and resource management activities within each park.