Description: This project provides for the collaboration between Dr. Sethu Raman, of the Department of Marine, Earth and Atmospheric Sciences at North Carolina State University (NCSU), Raleigh, and Dr. A. Prabhu of the Centre for Atmospheric Sciences at the Indian Institute of Science (ISc)in Bangalore. They plan to study the atmospheric boundary layer and the land surface processes in the tropics with special emphasis on applications to agriculture and air pollution meteorological aspects and climate modeling. Specific objectives are: study the mean and turbulent structure of convective boundary layer in the tropics; study the mean and turbulent structure of the nocturnal boundary layer in the tropics which is normally associated with stable conditions with very limited diffusion and can lead to high ground concentrations of pollutants; study the evapo-transpiration processes under different crop and planetary boundary layer (PBL) conditions; study the effect of the changes in the coriolis parameter on the PBL processes with particular emphasis on the nocturnal layer; and determine methods of incorporating these processes in mesoscale numerical methods. Scope: The two scientists have been interacting for about four years including a sabbatical by Dr. Raman at the IISc. They both have extensive qualifications in the research topics, and the two institutes have extensive capabilities to support the research. Bangalore has recently been selected by the Government of India for establishing a national center for boundary layer studies with a 300 meter tower, which should aid this research. The area of study is useful in predicting diffusion of pollutants under various conditions, and should be of benefit to the U.S. and India.