6. Applications of Remote Sensing and Geographical Information System (GIS) in Assimilation of Environmental Data

Remote Sensing (RS) is the science and art of obtaining information about an object without touching or changing the object, specifically, the Earth’s surface or atmosphere (Lillesand et al. 2004). Remote Sensing is basically used by the scientific community for mapping and monitoring of natural resources on the surface of the earth. Remote sensing images provide reliable surface information for large spatial areas. The satellite images of an area are records of its changing hydro-geomorphology over time. In India, National Remote Sensing Centre (NRSC), Hyderabad maintains databases of earth surface images using various sensors, viz. PAN, LISS I, LISS II, LISS III, OCM, WIFS, and AWIFS. Satellites providing images are IRS-1A, 1B, 1C, 1D, P5, P6 and OCEANSAT. India currently has 5 Cartosat satellites (1, 2, 2A, 2B, and 2C) with resolution ranging from 1 m (Cartosat-2) to the most recent one (Cartosat 2C launched on 22 June 2016) providing images with resolution of 25 cm. These high resolution images can be effectively used for making digital elevation models (DEM), water resources management and several other applications.