My primary areas of interest involve atmospheric radiative transfer and remote sensing of clouds and aerosols. I have innovated a unified theory for light scattering by nonspherical ice crystals of all sizes and shapes, similar to the Lorenz-Mie theory for spherical droplets, and developed a number of physically-based approximations for the transfer of solar and thermal infrared radiation in cloudy and aerosol atmospheres for applications to remote sensing and climate modeling. In recent years, I have focused my research on three areas. The first is concerned with the development of remote sensing algorithms for the detection of ubiquitous thin and invisible cirrus and for the retrieval of the optical and microphysical properties of clouds and aerosols with validations utilizing spectral channels that are and will be available from operational research satellites. The second topic is associated with the development of an efficient three-dimensional radiative transfer computer program for inhomogeneous clouds for potential incorporation in cloud and climate models. Finally, I am also investigating light scattering and spectroscopic features involving ice crystal clouds generated in a laboratory cloud chamber.
