Satellite remote sensing: its evolution and synergism with GIS technology
Since the launch of the first civilian earth monitoring satellite in 1972, the field of satellite remote sensing has evolved substantially. Begun on a purely experimental basis with relatively crude imaging systems, space remote sensing has become a source of remarkably detailed land management information that is available in GIS-compatible digital format on a regular basis globally. At the same time, providing satellite remote sensing data products to data users has become a rapidly expanding commercial enterprise of international scale. To this juncture, a critical factor limiting the application of satellite data in day-to-day land management at virtually all levels of government has been the ambivalence with which the U.S. has developed and administered its space remote sensing policy at the national level. That is, the political-institutional process leading to the “privatization of the U.S. Landsat program has been an extremely convoluted one that has been replete with complex policy issues. While literally scheduled for termination during the spring of 1989, the Landsat program has since received renewed governmental attention and support. The National Space Council and the Office of Management and Budget are currently reviewing options aimed at ensuring the program’s long-term continuation. Given both the technical and institutional evolution of space remote sensing internationally, satellite data are certain to become a primary GIS data source across the local to global continuum of GIS applications. It is in this context that this article briefly summarizes the history and current status of space remote sensing and its synergism with GIS technology.