HR: 0800h
AN: A41B-0428    [Abstracts]
TI: Parameterization of Shortwave and Longwave Radiative Properties of Ice Clouds for Use in Climate Models
AU: * Hong, G
EM: hong@ariel.met.tamu.edu
AF: Department of Atmospheric Sciences, Department of Atmospheric Sciences, Texas A&M University, College Station, TX 77843,
AU: Yang, P
EM: pyang@ariel.met.tamu.edu
AF: Department of Atmospheric Sciences, Department of Atmospheric Sciences, Texas A&M University, College Station, TX 77843,
AU: Heymsfield, A
EM: heyms1@ucar.edu
AF: National Center for Atmospheric Research, National Center for Atmospheric Research, Boulder, CO 80307,
AU: Baum, B A
EM: bryan.baum@ssec.wisc.edu
AF: Space Science and Engineering Center, University of Wisconsin-Madison, Madison, WI 53706.,
AU: Huang, H
EM: allenh@ssec.wisc.edu
AF: Space Science and Engineering Center, University of Wisconsin-Madison, Madison, WI 53706.,
AU: Hu, Y X
EM: y.hu@larc.nasa.gov
AF: NASA Langley Research Center, NASA Langley Research Center, Hampton, VA 23681,
AB: Climate modeling requires that the parameterization of the radiative effects of ice clouds be as accurate as possible. In this study, new parameterization of shortwave and longwave radiative properties has been developed on the basis of simulated single-scattering properties of nonspherical ice crystals and in-situ measurements of the microphysical properties of ice clouds observed during several field campaigns. Since the computation of the solar or infrared spectral radiation by accumulating individual bands over the whole spectral is computational costly, a common efficient method to calculate spectral radiation is based on several broad bands. Six parameterization schemes using different broad bands have been performed for shortwave and longwave radiative properties of ice clouds. The computed ice cloud radiative forcing at the top of atmosphere and Earth surface and heating rate from the parameterization schemes have been compared. It is found that the results from the different parameterizations agree well with each other. The relative errors of the results are generally less than 3%. The present parameterizations have been validated by comparing the ice cloud radiative forcing inferred from the parameterization schemes with those without parameterizing. The maximum error is about 5%. Moreover, the parameterizations have been applied to investigate the sensitivity of the radiative forcing and heating rate to the microphysical, macrophysical, and optical properties of ice clouds.
DE: 0321 Cloud/radiation interaction
DE: 3310 Clouds and cloud feedbacks
DE: 3337 Global climate models (1626, 4928)
DE: 3359 Radiative processes
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting