HR: 17:35h
AN: A54A-07    [Abstracts]
TI: Ground-based Measurements of Surface Reflectivity and Emissivity over Desert Regions
AU: * Tsay, S
EM: tsay@climate.gsfc.nasa.gov
AU: Ji, Q J
A54A-07 AU: Hansell, R A
A54A-07 AU: Hsu, N C
A54A-07 AB: The differential warming/cooling effects exerted by atmospheric aerosols constitute one of the most uncertain factors in climate change related research. This is especially true over the desert regions. One of the key ingredients for achieving accurate aerosol retrievals from satellite observations is comprehensive understanding of surface characteristics. To assist satellite retrievals of aerosol properties over desert regions, we deployed scanning spectroradiometer and microwave radiometer during the United Arab Emirates Unified Aerosol Experiment and the Aerosol Characterization Experiment-Asia to characterize the surface reflectivity and emissivity. Working under daytime air temperature of 35-45§C (surface skin temperature of 40-65§C) and a wide range of relative humidity (10-80%), we have surveyed a variety of desert sites over the Arabian Gulf and Northwestern China. The color of the surface ranged from dull white near the coast (the remains of oceanic washup) to pinkish-red Arabian (or yellowish Chinese) inland, and the texture of the surface changed from fine sand to small dark-colored gravel. The surface spectral Bidirectional Reflectance Factors (ratio of radiance measurements reflected from a targeted surface and from a spectral-angular featureless referencing plate) and Lambertian Emissivity (ratio of radiance measurements emitted from a targeted surface and from Planck functions of surface skin temperature) will be presented and implication be discussed. To fully characterize a desert surface in the field is an important but challenging task.
DE: 1640 Remote sensing (1855)
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005