Retrieving and Understanding the Properties of Dust Aerosol and Its Radiative Effects Using the Combination of Passive and Active Satellite Observations

Desert dust, one of the most abundant aerosols in the atmosphere, is recognized as an integral component of the Earth system that influences weather and climate via a suite of complex interactions with the energy, water, and carbon cycles. Dust storms also cause detrimental losses of human life and economic activities through degrading air quality, spreading diseases, disrupting transportation, and reducing efficiency of solar power generation.

At present and in the foreseeable future, satellite-based remote sensing is the only means to monitor the generation, transport, and distribution of dust aerosols on regional to global scales. Over the past few decades, many retrieval methods have been developed to infer the total aerosol optical depth (AOD) from satellite observations, but there are only a handful of algorithms to separate the portion of dust from the total AOD. In this talk, I will first provide an overview of two dust AOD retrieval algorithms and our recent study to compare them and use them to understand the variability of dust over the last ~15 years. In the second part of the talk, I will introduce our recent studies to combine both shortwave and longwave, both active and passive satellite sensors to understand the better retrieve dust properties, especially dust particle size, in the light of recent discussions of the mysterious long-range transport of giant dust particles. Finally, I will go over our recent studies of the direct radiative effects of dust aerosols using satellite observations followed by a brief outlook of future research directions.