Remote Sensing is A Powerful Tool, But Not a Panacea in Itself

Remote sensing (RS), in particular spaceborne remote sensing has come a long way, ever since the successful launch of Earth Resources Technology Satellite-1 (renamed as LANDSAT-1) in 1972 by the National Aeronautics and Space Administration (NASA) of the United States. A large number of remote sensing satellites launched subsequently by different national space agencies, including India and a few commercial private operators have provided a variety of data to study the earth’s surface and, measurements of the atmosphere and the oceans. These datasets have been utilized in a number of programmes to inventory earth’s resources, study their condition and investigate changes over a period of time. A variety of application programmes, viz. agricultural crop production forecasts at national/sub national level, forest extents, identifying areas of deforestation, inventory of surface water bodies, snow cover, glaciers and their retreat, coastal zones, urban areas and their sprawl, geological resources, desertification, updation of topographic and thematic maps, etc., have been developed and used in many countries to advance national development. Data obtained from some of the specific satellites devoted to ocean and atmospheric observations have been used to improve ocean state forecasting, exploitation of some of the ocean resources and improved weather forecasting. Satellite observations have found an important and crucial role in facilitating early warning of some of the disasters, in monitoring and mitigation exercises, and in damage assessment. RS data have also been used in studying earth system science and in understanding various earth processes. RS has thus assumed the role of an indispensable tool.