HR: 09:30h
AN: A51C-06    [PDF]
TI: Tropical deep convection observed by TRMM satellite
AU: * Lin, B
EM: bing.lin@nasa.gov
AF: NASA Langley Research Center, MS 420 Atmospheric Sciences Research, Hampton, VA 23681
AU: Minnis, P
EM: Patrick.Minnis@nasa.gov
AF: NASA Langley Research Center, MS 420 Atmospheric Sciences Research, Hampton, VA 23681
AU: Chambers, L H
EM: Lin.H.Chambers@nasa.gov
AF: NASA Langley Research Center, MS 420 Atmospheric Sciences Research, Hampton, VA 23681
AU: Hu, Y
EM: Yongxiang.Hu@nasa.gov
AF: NASA Langley Research Center, MS 420 Atmospheric Sciences Research, Hampton, VA 23681
AB: Incomplete knowledge of cloud radiative properties of tropical deep convective clouds (DCC) and their responses to sea surface temperature (SST) variations causes large uncertainties in climate change predictions of general circulation models. This study uses more accurate and complete TRMM satellite datasets to answer some related fundamental questions. The measurements from multiple instruments on board TRMM satellite are collocated into an integrated data set, that is, this study combines the DCC data of CERES shortwave (SW) and longwave (LW) measurements, CERES cloud properties obtained from narrowband VIRS visible and infrared measurements, and TMI microwave retrievals of precipitation, water cloud properties, boundary layer moisture, and sea surface evaporation. Additionally, the variations of these DCC properties with SST, wind fields, and other environmental conditions are investigated. The study finds that most DCCs have effective radii less than 400km with some systems larger than 800km. DCC occurrences generally increase with SST, especially when SST reaches about 301K. For the warmest SST ($>$ about 304K) DCC frequencies drop significantly due to a smaller total area having that high SST. Less favorable boundary conditions for convergence may be another reason. Although DCC rain rates increase with SST, the change of DCC size is not significant. Large-scale dynamics also play important roles.
DE: 0320 Cloud physics and chemistry
DE: 1620 Climate dynamics (3309)
DE: 3359 Radiative processes
DE: 3360 Remote sensing
SC: Atmospheric Sciences [A]
MN: 2003 Fall Meeting