HR: 16:48h
AN: A44A-05 [Abstracts]
TI: Retrieval of cloud properties from MODIS and AIRS
AU: * Li, J
EM: Jun.Li@ssec.wisc.edu
AF: Cooperative Institute for Meteorological Satellite Studies, 1225 West Dayton Street, Madison, WI 53706
United States
AU: Huang, H
EM: Allen.Huang@ssec.wisc.edu
AF: Cooperative Institute for Meteorological Satellite Studies, 1225 West Dayton Street, Madison, WI 53706
United States
AU: Liu, C
EM: cyliu@ssec.wisc.edu
AF: Cooperative Institute for Meteorological Satellite Studies, 1225 West Dayton Street, Madison, WI 53706
United States
AU: Schmit, T
EM: TimS@ssec.wisc.edu
AF: NOAA/NESDIS, Office of Research and Applications, 1225 West Dayton Street, Madison, WI 53706
United States
AU: Menzel, W
EM: PaulM@ssec.wisc.edu
AF: NOAA/NESDIS, Office of Research and Applications, 1225 West Dayton Street, Madison, WI 53706
United States
AB:
The Moderate-Resolution Imaging Spectroradiometer (MODIS) and the Atmospheric Infrared Sounder (AIRS) measurements from
NASA's Earth Observing System's (EOS) Aqua satellite enable global monitoring of the distribution of clouds during day and
night. The MODIS is able to provide a high spatial resolution (1 ~ 5km) cloud mask, cloud classification mask (CCM), cloud
phase mask (CPM), cloud-top pressure (CTP), effective cloud amount (ECA) during the daytime and the nighttime, as well as
cloud particle size (CPS) and cloud optical thickness (COT) at 0.55 mm during the daytime. The AIRS high spectral resolution
measurements reveal cloud properties with coarser spatial resolution (13.5 km at nadir). The combined MODIS/AIRS systems
offer the opportunity for improved cloud products over those possible from either system alone; the improvement on CTP and
ECA retrievals has been demonstrated with both simulated and real radiances with wavenumbers between 650 - 790 cm-1 (12.66 -
15.38 mm). A fast cloudy radiative transfer model for AIRS accounting for cloud scattering and absorption is described in
this paper. The difference between the fast cloud model and the Discrete Ordinates Radiative Transfer (DISORT) calculation
is less than 0.5 K for most AIRS spectral channels. One-dimensional variational (1DVAR) and minimum residual (MR)
methodologies are used to retrieve the CPS and COT from AIRS longwave window region (790 - 970 cm-1 or 10.31 - 12.66 mm, and
1050 - 1130 cm-1 or 8.85 - 9.52 mm) cloudy radiance measurements. Operational CPS product from the high spatial resolution
MODIS serves as background and first guess information in the AIRS 1DVAR cloud retrieval (here and after, refers as
MODIS+AIRS 1DVAR), while the cloud microphysical property retrievals are also derived from AIRS radiances with the MR
algorithm (here and after, refers as AIRS MR). In both 1DVAR and MR procedures, the CTP is derived from the AIRS radiances
of CO2 channels while the cloud phase information is derived from the collocated MODIS 1km phase mask for AIRS CPS and COT
retrievals. In addition, the collocated 1km MODIS cloud mask refines the AIRS cloud detection in both the MODIS+AIRS 1DVAR
and the AIRS MR procedures. The atmospheric temperature profile, moisture profile and surface skin temperature used in the
AIRS cloud retrieval processing are from the European Center for Medium-range Weather Forecasting (ECMWF) forecast analysis.
The results from the MODIS+AIRS 1DVAR are compared with the operational MODIS products and the AIRS MR cloud microphysical
property retrieval. A Hurricane Isabel case study shows that the MODIS+AIRS 1DVAR retrievals have high correlation with
either the operational MODIS cloud products or the AIRS MR cloud property retrievals. The MODIS+AIRS 1DVAR provides an
efficient way for cloud microphysical property retrieval during the daytime, while the AIRS MR provides the cloud
microphysical property retrievals during both the daytime and nighttime.
DE: 6924 Interferometry
DE: 3359 Radiative processes
DE: 3360 Remote sensing
DE: 3394 Instruments and techniques
DE: 3260 Inverse theory
SC: Atmospheric Sciences [A]
MN: 2004 AGU Fall Meeting