HR: 11:35h
AN: SM12B-05    [Abstracts]
TI: Studying Radiation Belt Electrons with Linear State-Space Models
AU: * Rigler, E J
EM: jrigler@lasp.colorado.edu
AF: HAO/NCAR, 3080 Center Green Dr., Boulder, CO 80301 United States
AU: * Rigler, E J
EM: jrigler@lasp.colorado.edu
AF: CU/LASP, 1234 Innovation Dr., Boulder, CO 80303 United States
AU: Baker, D N
EM: daniel.baker@lasp.colorado.edu
AF: CU/LASP, 1234 Innovation Dr., Boulder, CO 80303 United States
AU: Vassiliadis, D
EM: vassi@lepgst.gsfc.nasa.gov
AF: ST at NASA/GSFC, Code 612.2, Greenbelt, MD 20771 United States
AU: Kanekal, S G
SM12B-05 AF: CU/LASP, 1234 Innovation Dr., Boulder, CO 80303 United States
AB: Linear state-space models offer a compact data-derived modeling framework for describing the linear dynamics of geophysical systems. This framework is better suited to physical interpretation than traditional linear filters; it readily incorporates multiple inputs; and it allows for potential coupling between state variables in a way that is difficult if not impossible to replicate with more typical transfer function models. In this study a low-order, multi-output state-space model is combined with a subset of solar wind observations to model relativistic electron flux at altitudes measured by the SAMPEX satellite. Since unanticipated or unmeasured inputs, nonlinearities, and measurement noise almost certainly lead to sub-optimal predictions, we use a variant of the well-known Kalman Filter to help mitigate these problems through adaptive parameter identification and data assimilation. This provides better separation of external perturbations, as well as predictable stochastic variations in measured electron fluxes, from the deterministic internal dynamics of the radiation belts. The result is improved spatial interpolation (specification), and temporal extrapolation (forecast), with respect to current empirical radiation belt models used in operational settings.
DE: 2720 Energetic particles: trapped
DE: 2784 Solar wind/magnetosphere interactions
DE: 7924 Forecasting (2722)
DE: 7984 Space radiation environment
SC: SPA-Magnetospheric Physics [SM]
MN: Fall Meeting 2005