HR: 1340h
AN: U43A-0850    [Abstracts]
TI: Climate Sensitivity and the Generation of Available Potential Energy
AU: * Romanski, J
EM: jr988@columbia.edu
AF: Department of Earth and Environmental Sciences Columbia University, Lamont Doherty Earth Observatory P.O. Box 1000 61 Route 9W, Palisades, NY 10964, United States
AU: Rossow, W B
EM: wbrossow@ccny.cuny.edu
AF: Department of Electrical Engineering City College and Graduate School City University of New York, Convent Avenue at 140th St., New York, NY 10031, United States
AB: The current climate is characterized by an energy cycle which is forced by the generation of available potential energy G (Lorenz, 1955). G may be divided into its zonal and eddy components (G_z and G_e), which depend on the correlation between the latitudinal temperature and diabatic heating gradients in the case of G_z, and the meridional temperature and diabatic heating gradients for G_e. We expect that the temperature and heating fields will change as the climate changes, resulting in different correlations and thus different characteristic G_z and G_e. This study examines the generation of available potential energy for the output of two models with significantly different climate sensitivities - the NCAR CCSM3 model on the low end of climate sensitivity at 2.7K for doubled CO₂, and the UKMO HadGEM1 on the high end at 4.4K for doubled CO₂. Using the output submitted to PCMDI for the IPCC AR4, G_z and G_e for each model are computed for the twentieth century simulation, and compared to G_z and G_e computed for the 2xCO₂ runs to explore how each model's energy generation relates to its climate sensitivity. Special attention is given to the partitioning between the various diabatic heating components.
DE: 1610 Atmosphere (0315, 0325)
DE: 3305 Climate change and variability (1616, 1635, 3309, 4215, 4513)
DE: 3309 Climatology (1616, 1620, 3305, 4215, 8408)
DE: 3337 Global climate models (1626, 4928)
SC: Union [U]
MN: 2007 Fall Meeting