HR: 12:10h
AN: NG32A-08    [Abstracts]
TI: Unstable Periodic Orbits and Predictability in a Large Atmospheric Dynamical System
AU: * Krishnamurthy, V
EM: krishna@cola.iges.org
AF: Center for Ocean-Land-Atmosphere Studies, Institute of Global Environment and Society, 4041 Powder Mill Road Suite 302, Calverton, MD 20705, United States
AU: * Krishnamurthy, V
EM: krishna@cola.iges.org
AF: Department of Climate Dynamics, George Mason University, Fairfax, VA 22030, United States
AB: The instability of periodic orbits in a two-layer quasi-geostrophic model has been studied to understand the structure of the chaotic attractors and the predictability of the system. As a step toward understanding the structure of the chaotic solutions of general circulation models, the two-layer model is studied for various spectral truncations by including many scales of motion. The model is selected to be large but still suitable to be studied as a dynamical system. The instability and bifurcations of periodic orbits for different spectral truncation levels and forcings have been studied, and multiple unstable periodic orbits have been found for certain forcings. The role of such unstable periodic orbits in determining the structure of the chaotic solutions and the growth and structure of errors are discussed. The change in the nature of the instability of the periodic solutions as the truncation level varies in the model is emphasized.
DE: 3399 General or miscellaneous
DE: 4410 Bifurcations and attractors
DE: 4420 Chaos (7805)
SC: Nonlinear Geophysics [NG]
MN: 2007 Fall Meeting