HR: 17:30h
AN: A34A-07 [Abstracts]
TI: Comparison of statistical properties of simulated and observed cumulus clouds during GoMACCS
AU: * Jiang, H
EM: hongli.jiang@noaa.gov
AF: NOAA Earth System Research Laboratory, 325 Broadway, Boulder, CO 80305, United
States
AU: Feingold, G
EM: graham.feingold@noaa.gov
AF: NOAA Earth System Research Laboratory, 325 Broadway, Boulder, CO 80305, United
States
AU: Jonsson, H
EM: hjonsson@nps.edu
AF: Naval Postgraduate School, 1 University circle, Monterey, CA 93943,
AU: Lu, M
EM: julialu@caltech.edu
AF: California Institute of Technology, 1200 E. California Blvd, Pasadena, CA 91125, United
States
AU: Chuang, P Y
EM: pchuang@pmc.ucsc.edu
AF: University of California, Santa Cruz, 1156 High St, Santa Cruz, CA 95064, United States
AU: Flagan, R C
EM: flagan@cheme.caltech.edu
AF: California Institute of Technology, 1200 E. California Blvd, Pasadena, CA 91125, United
States
AU: Seinfeld, J H
EM: seinfeld@caltech.edu
AF: California Institute of Technology, 1200 E. California Blvd, Pasadena, CA 91125, United
States
AB:
We present comparisons of the statistical properties of clouds generated by Large Eddy Simulations (LES) with
aircraft observations of non-precipitating, warm cumulus clouds made during the Gulf of Mexico Atmospheric
Composition and Climate Study (GoMACCS). Aircraft data were sampled with the Center for Interdisciplinary
Remotely-Piloted Aircraft Studies (CIRPAS) Twin Otter airplane. Five flights that are most suitable for studying
aerosol-cloud interactions are selected. The model simulations are initiated with observed environmental
profiles. The simulations are used to generate an ensemble of thousands of cumulus clouds for statistically
meaningful evaluations. Comparison focuses on the statistical properties of a set of dynamical and
thermodynamical variables: cloud liquid water content, number mixing ratio of cloud droplets, drop effective
radius, updraft velocity, and the distribution of cloud sizes. In general, good agreement between the simulated
and observed clouds is achieved, despite big differences in sample size between the model output and the
aircraft data. These comparisons, together with the excellent agreement between observed and simulated cloud
size distributions, suggest that the LES is able to successfully generate the cumulus cloud populations that were
present during GoMACCS.
DE: 3307 Boundary layer processes
DE: 3310 Clouds and cloud feedbacks
DE: 3311 Clouds and aerosols
DE: 4255 Numerical modeling (0545, 0560)
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting