Our research is focused upon using satellite data for studying the earth-atmosphere system, regional to global climate and particulate matter air quality. Of particular interest is combining multiple sensors from satellites - often called data fusion - to study the effect of clouds, aerosol, and air pollution. Several satellite sensors have been used from both polar orbiting and geostationary platforms. Some of the satellite sensors used include AVHRR, GOES, LANDSAT, MODIS, ERBE, CERES, MISR, SCARAB, VIRS, TOMS, ASTER, and SAGE We also use a variety of ground, ship and space shuttle data for validating and characterizing clouds and aerosols. These include AERONET, AIRS PM2.5, IMPROVE, SMART, and MAPS. We also use insitu data from aircrafts to study aerosols and clouds during field campaigns such as SCAR-B, PRIDE, UAE^2, SAFARI, ACE-Asia to improve and refine satellite algorithms. Recently our group has also used mesoscale models for studying processes related to clouds and aerosols. Our research has been published in national and international journals such as Geophysical Research Letters, International Journal of Remote Sensing, Journal of Applied Meteorology, Tellus B, Journal of Atmospheric Sciences and other journals. We thank our collaborators across the world who provide data, expert advice, and publish joint peer reviewed papers with us.