HR: 09:33h
AN: A31C-05    [Abstracts]
TI: Ice Cloud Optical Depth from MODIS Cirrus Reflectance
AU: * Meyer, K
EM: kmeyer@climate.gsfc.nasa.gov
AF: NASA/GSFC, Mail Code 613.2, Greenbelt, MD 20771, United States
AU: Yang, P
EM: pyang@ariel.met.tamu.edu
AF: Texas A&M University, 3150 TAMU, College Station, TX 77843, United States
AU: Gao, B
EM: bo-cai.gao@nrl.navy.mil
AF: Naval Research Laboratory, Code 7230, Washington, DC 20375, United States
AB: Here, the retrieval of ice cloud microphysical properties based on the 1.38-μm "cirrus detection" channel of the Moderate-resolution Imaging Spectroradiometer (MODIS) is detailed. The 1.38-μm channel is located in a strong water vapor absorption band, thus, under most circumstances, its measured reflectance is solely due to ice clouds. This band, in combination with a visible channel (here, 0.66-μm), can be used to derive the cirrus reflectance, a parameter included in the operational MODIS atmosphere product. A new method has been developed to derive ice cloud optical depth on a global scale from the cirrus reflectance using pre-calculated look-up tables. Forward radiative transfer calculations, used to construct the look-up library, are carried out using the discrete-ordinates radiative transfer method with the new bulk-scattering properties of ice clouds developed for the Collection 005 MODIS cloud product. This method is complimentary to the MODIS operational cloud retrieval algorithm for the case of ice clouds.
DE: 3311 Clouds and aerosols
DE: 3359 Radiative processes
DE: 3360 Remote sensing
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting