Asian dust height and infrared optical depth retrievals over land from hyperspectral longwave infrared radiances

Abstract

The dust top height and infrared optical depth over land are retrieved from the Atmospheric Infrared Sounder (AIRS) longwave infrared measurements by using a one-dimensional-variation retrieval algorithm for different Asian dust storms. By combining particle size measurements from a 10-year ground observation data set from the Dunhuang Skynet station located to the east of the Taklimakan Desert in China and the Optical Properties of Aerosols and Clouds data set of optical properties, the mineral dust scattering and absorption coefficients are obtained and then used to compute brightness temperatures with RTTOV 9.3. The retrieved dust thermal infrared optical depths are compared with the Ozone Monitoring Instrument and Moderate Resolution Imaging Spectroradiometer (MODIS) products. The retrieved dust top heights are compared against the extinction backscatter profiles obtained from the Cloud-Aerosol Lidar with Orthogonal Polarization lidar. Infrared optical depths from AIRS correlate favorably with visible optical depths from MODIS, and dust top heights agree reasonably with lidar observations for the single-layered dust storms over the Taklimakan Desert. © 2012 American Geophysical Union. All Rights Reserved.