Abstract. Recently, the importance of integration of remote sensing and geographic information system (GIS) to study hydrologic processes has been realized by water-resources workers. However, the interface between remotely sensed data and GIS is still weak and many problems must be solved before it becomes widely available. In the meantime, the public use of satellite data to manage water resources is still in its infancy, and more application techniques are urgently in need of development. Thus this chapter is separated into two major parts. The first part is to introduce general information about remote sensing systems, GIS, and the global positioning system (GPS). The second part is to exemplify successful applications of the integration of remote sensing and GIS in hydrologic studies such as land use/land cover classification, precipitation, soil moisture, evapotranspiration, water extent, groundwater, water quality, and runoff.
IntroductionThe endless recirculation of water in the atmosphere-hydrosphere-lithosphere is known as the hydrologic cycle. The cycle can be studied according to the particular scale of reference i.e., global scale, basin scale, etc. From the hydrological point of view, the basin scale cycle is emphasized. The basin-scale cycle is considered to be a continuous circulation of water from water vapor to precipitation, stream flow, lakes, reservoirs, soil moisture, groundwater, and out of basin transfer, to the return to water vapor through evaporation and transpiration. Within a basin, the dynamics of the hydrologic processes are governed partially by the temporal and spatial characteristics of inputs and outputs and the land use/land cover conditions. Currently, little is known about the accuracy of the estimation of hydrologic parameters in a given area, primarily because of the wide variation of the distribution in