HR: 10:56h
AN: A42C-04    [Abstracts]
TI: Cloud Ice: A Climate Model Challenge With Signs and Expectations of Progress
AU: LI, F
EM: duane.waliser@jpl.nasa.gov
AF: JPL, 4800 Oak Grove, Pasadena, CA 91109, United States
AU: * Waliser, D
EM: duane.waliser@jpl.nasa.gov
AF: JPL, 4800 Oak Grove, Pasadena, CA 91109, United States
AU: Bacmeister, J
EM: bacmj@gmao.gsfc.nasa.gov
AF: GSFC, NASA, Greenbelt, MD 99999,
AU: Chern, J
EM: jchern@agnes.gsfc.nasa.gov
AF: GSFC, NASA, Greenbelt, MD 99999,
AU: del Genio, T
EM: adelgenio@giss.nasa.gov
AF: GISS, NASA, New York, NY 99999,
AU: Jiang, J
EM: Jonathan.H.Jiang@jpl.nasa.gov
AF: JPL, 4800 Oak Grove, Pasadena, CA 91109, United States
AU: Kharitondov, M
EM: marat@atmos.colostate.edu
AF: Atmos, CSU, Fort Collins, CO 99999,
AU: Liou, K
EM: knliou@atmos.ucla.edu
AF: ATMOS, UCLA, Los Angeles, CA 99999,
AU: Meng, H
EM: Huan.Meng@noaa.gov
AF: NESDIS, NOAA, Camp Springs, MD 99999,
AU: Minnis, P
EM: Patrick.Minnis-1@nasa.gov
AF: Langley, NASA, Virginia, 99999,
AU: Rossow, B
EM: wbrossow@gmail.com
AF: GISS, NASA, New York, NY 99999,
AU: Stephens, G
EM: stephens@atmos.colostate.edu
AF: Atmos, CSU, Fort Collins, CO 99999,
AU: Sun-Mack, S
EM: szedung.sun-mack-1@nasa.gov
AF: Langley, NASA, Virginia, 99999,
AU: Tao, W
EM: tao@agnes.gsfc.nasa.gov
AF: GSFC, NASA, Greenbelt, MD 99999,
AU: Vane, D
EM: dvane@mail.jpl.nasa.gov
AF: JPL, 4800 Oak Grove, Pasadena, CA 91109, United States
AU: Woods, C
EM: Christopher.P.Woods@jpl.nasa.gov
AF: JPL, 4800 Oak Grove, Pasadena, CA 91109, United States
AU: Tompkins, A
EM: adrian_tompkins@yahoo.co.uk
AF: ECMWF, ECMWF, Reading, 99999, United Kingdom
AU: Wu, D
EM: dwu@mls.jpl.nasa.gov
AF: JPL, 4800 Oak Grove, Pasadena, CA 91109, United States
AB: Global climate models (GCMs), including those assessed in the IPCC AR4, exhibit considerable disagreement in the amount of cloud ice – both in terms of the annual global mean as well as their spatial variability. Global measurements of cloud ice have been difficult due to the challenges involved in remotely sensing ice water content (IWC) and its vertical profile – including complications associated with multi-level clouds, mixed-phases and multiple hydrometer types, the uncertainty in classifying ice particle size and shape for remote retrievals, and the relatively small time and space scales associated with deep convection. Together, these measurement difficulties make it a challenge to characterize and understand the mechanisms of ice cloud formation and dissipation. Fortunately, there are new observational resources recently established that can be expected to lead to considerable reduction in the observational uncertainties of cloud ice, and in turn improve the fidelity of model representations. Specifically, these include the Microwave Limb Sounder (MLS) on the Earth Observing System (EOS) Aura satellite, and the CloudSat and Calipso satellite missions, all of which fly in formation in what is referred to as the A-Train. Based on radar and limb-sounding techniques, these new satellite measurements provide a considerable leap forward in terms of the information gathered regarding upper-tropospheric cloud IWC as well as other macrophysical and microphysical properties. In this presentation, we describe the current state of GCM representations of cloud ice and their associated uncertainties, the nature of the new observational resources for constraining cloud ice values in GCMs, the challenges in making model-data comparisons with these data resources, and prospects for near-term improvements in model representations.
DE: 3311 Clouds and aerosols
DE: 3337 Global climate models (1626, 4928)
SC: Atmospheric Sciences [A]
MN: 2007 Fall Meeting