FIGURE 1.1 History of the Landsat suite of remote sensing satellites. When Landsat 6 failed on launch in 1993, a gap in data collection was avoided by the fortuitous survival of Landsat 5 far beyond its design life of 3 years. It was finally decommissioned in 2013. In 2003, Landsat 7 suffered the loss of the scan line corrector on the Enhanced Thematic Mapper Plus instrument, resulting in the loss of 25 percent of the data for any given scene. NOTE: LDCM, Landsat Data Continuity Mission, now Landsat 8. SOURCE: U.S. Geological Survey, “Landsat 1 History. July 23, 1972-January 6, 1978,” available at http://landsat.usgs.gov/about_mission_history.php.
Land imaging data from the Landsat series of satellites forms the basis and model for civil remote sensing in the United States and has been used for applications ranging from wildfire management, to urban planning, to disaster mitigation and response. Figure 1.2, for example, shows urban growth in the Las Vegas, Nevada, area between 1990 and 2010. Landsat data are used operationally by virtually every U.S. land management agency to define broad land cover categories—through the U.S. Geological Survey (USGS) National Land Cover Database—and to monitor rapid changes, such as pre- and postburn forest conditions (Table 1.1). The federal government owns between 635 and 640 million acres of land, which constitutes 28 percent of the 2.27 billion acres of land in the United States. Four agencies administer 609 million acres of this land: the U.S. Forest Service (USFS) in the Department of Agriculture and the National Park Service, Bureau of Land Management, and the Fish and Wildlife Service in the Department of the Interior (DOI). Most of these lands are in the western states and Alaska. In addition, the Department of Defense (DOD) administers 19 million acres in military bases, training ranges, and more.4
Specific examples of benefits to the United States made possible by analysis of Landsat data include the following:
• Agricultural forecasting and management— The U.S. Department of Agriculture uses Landsat data to monitor global crop supplies and stocks to forecast shortfalls or gluts of various crops on the market. The multimillion-dollar U.S. agricultural commodities market relies on these crop predictions when conducting futures trading.5 These important functions benefit U.S. food and economic security as well as national security.
• Monitoring climate change impacts— Landsat data facilitate the monitoring of the distribution and rates of impacts of climate change on remote regions, including glaciers, rainforests, and permafrost, and coral reefs—often early harbingers of climate and temperature change.6 The U.S. Climate Change Science Program, representing 15 federal agencies, has identified Landsat as a critical observatory for climate and environmental change research due to the unbroken length of the Landsat record and its importance to identifying the root causes and impacts
4 R.W. Gorte, C.H. Vincent, L.A. Hanson, and M.R. Rosenblum, Federal Land Ownership: Overview and Data, R42346, Congressional Research Service, available at http://www.fas.org/sgp/crs/misc/R42346.pdf, July 29, 2013.
5 J.R. Irons, Landsat’s Critical Role in Agriculture, NASA/USGS Fact Sheet, 2012, available at http://landsat.gsfc.nasa.gov/pdf_archive/Landsat_AG_fs_4web.pdf.
6 For example, F. Paul, A. Kääb, and W. Haeberli, Recent glacier changes in the Alps observed by satellite: Consequences for future monitoring strategies, Global and Planetary Change 56:111-122, 2007; A.C. Baker, P.W. Glynn, and B. Riegl, Climate change and coral reef bleaching: An ecological assessment of long-term impacts, recovery trends and future outlook, Estuarine, Coastal and Shelf Science 80:435-447, 2008.