HR: 1340h
AN: NG23D-0112    [Abstracts]
TI: Nonlinear Spatial-Temporal Spectral Analyses for Diagnosing Solar 11-Year Signal in the Northern Hemisphere Atmosphere
AU: * Powell, A M
EM: al.powell@noaa.gov
AF: NOAA/NESDIS/ORA and IMSG, Inc., 5200 Auth Road WWB/701, Camp Springs, MD 20746 United States
AU: Chen, M
EM: ming.chen@noaa.gov
AF: NOAA/NESDIS/ORA and IMSG, Inc., 5200 Auth Road WWB/701, Camp Springs, MD 20746 United States
AB: The major dilemma in the search for a Sun-Earth connection is tiny solar output variations appear insignificant relative to dynamic atmospheric changes while many synoptic and climatic parameters are found to be significantly correlated with the solar variation at different time scales. Based on previous analysis, the solar variations are assumed to exert their influence through nonlinear modulation of the existing dynamic or thermodynamic processes. Nonlinear spatial-temporal spectral analysis is helpful for identifying nonlinear solar signals in the atmospheric observations and establishing nonlinear feedback mechanisms. Using the 50-year NCEP/NCAR reanalysis data, an extensive spatial-temp spectral analysis is performed. Fourier transformation is first applied latitude by latitude to get zonal waves of different spatial scales. The time series of the amplitude (energy) of each wave is filtered to isolate different time-scale waves. From the viewpoint of linear wave theory, these waves are assumed to carry atmospheric energy derived from the original sources and the atmospheric response to the source functions. The temporal change of wave amplitude is closely related to the source energy change, such as boundary condition change, or nonlinear adjustment of background state (energy exchange from different scales), etc. The relevant spatial-temp spectral structure change associated with solar variations will be addressed in this study. The results suggest nonlinear atmospheric processes may couple solar variation with atmospheric variations.
DE: 4415 Cascades
DE: 4455 Nonlinear waves, shock waves, solitons (0689, 2487, 3280, 3285, 4275, 6934, 7851, DE: 4460 Pattern formation
DE: 4465 Phase transitions
DE: 4475 Scaling: spatial and temporal (1872, 3270, 4277)
SC: Nonlinear Geophysics [NG]
MN: Fall Meeting 2005