Study Dust Optical and Radiative Properties Using Optimal Morphological Sets

Texas A&M Research Foundation, College Station TX

Investigators

Abstract

Airborne dust and smaller aerosol particles play an important role in the earth's climate system by scattering light and longer wavelength (e.g., thermal) radiation passing through the atmosphere. To the extent that their impacts are imperfectly known, they also complicate interpretation of TOA (top of atmosphere) emissions of thermal energy and scattered/reflected light as remotely sensed by satellites. Both aspects are of crucial importance in our efforts to obtain a physically representative, quantitatively accurate understanding of global circulation dynamics and any overlain signals corresponding to climate change. The fact that dusts and aerosols exhibit a myriad of differing sizes, shapes and compositions greatly complicates this problem. The primary objective of this research effort is to explore the feasibility of reducing this complexity via definition and development a more manageable number of "optimal morphological parameters" associated with representative particle types. This project will develop and validate mathematically sophisticated methods for estimating both radiative and light-scattering properties of such particles that are far more efficient in their use of computer time than currently available methods. Once fully tested and documented, associated computer codes will be made widely available to the broader research community for further use and evaluation. The intellectual merit of this effort is centered on improving our knowledge of the optical and radiative properties of airborne dust and aerosols. The resultant findings will have direct applications in the study of the Earth's radiative budget as well as remote sensing of atmospheric properties from both ground-based and orbital platforms. Broader impacts of this research will include increased ability to accurately specify the "direct radiative forcing" (e.g., induced warming and/or cooling) associated with both natural and anthropogenically-generated aerosols on our climate via sophisticated global-scale computer models. This project will also support the education and training of several graduate students in the interdiscplinary area marked by the intersection of atmospheric physics and classical electromagnetics.