Description: This proposal supports a collaborative project by Drs. H.W. Hiser and T.N. Veziroglu of the University of Miami, Coral Gables, Florida and Drs. M.G. Srinivas, and G.T. Marathe of the Indian Institute of Technology of Bombay, India. They plan to conduct a theroetical and experimental study of water run-off estimations using data developed from remote sensing systems. The reliablity of a water estimation study depends on the accuracy of estimates of rainfall and the loss of water before it joins a main stream. Surface-based digitized radar systems and geostationary satellite systems have the capability to provide more complete and accurate data. A watershed model will be developed using digitized radar systems at the University of Miami and geostationary satellite data obtained from NOAA as the rainfall data to the model. Raingage data available in Florida will be used for ground truth of the remote-sensed rainfall data. The results will be tested in India. Data will be obtained from the radar system at Madras, India. Landsat data will be available form both U.S. and Indian geostationary satellites. Scope: The study seeks to: develop an improved model for estimating the run-off water by taking into account precipitation, evapotranspiration and infiltration, as well as the location, land cover, land form and drainage form, as function of time, through utilizing remote sensing data; verify the model calculations against observational data gathered in India; refine the model and apply it to selected regions in India. The development of reliable watershed run-off model based on testing and research in the two countries under vastly different conditions should produce a model of wider applicability leading to more efficient and safer water run-off management around the world. Correct estimation of rain water run-off is of importance to the United States, which has the highest per capita water consumption, and India, which has one of the largest, and high density, populations in the world. Funding: This project is being supported under two grants INT 8905173 to University of Miami: FY90 US$23,003 plus $8,235 in Indian currency FY91 US$24,276 plus $9,118 in Indian currency FY92 US$25,235 plus $10,000 in Indian currency INT8922266 to Indian Institute of Technology, Bombay: FY90 $100,965 in Indian currency