HR: 0800h
AN: SA51A-0244    [Abstracts]
TI: IFM-Modeled Response of the High-Latitude Ionosphere to Auroral Dynamics Based on Auroral Observations Acquired with the Visible Imaging System(VIS) on the Polar Spacecraft
AU: * Bekerat, H
EM: HBekerat@poptemp.gsfc.nasa.gov
AF: NASA Goddard Space Flight Center, Space Weather Laboratory, Greenbelt, MD 20771,
AU: Sigwarth, J
EM: John.B.Sigwarth@nasa.gov
AF: NASA Goddard Space Flight Center, Space Weather Laboratory, Greenbelt, MD 20771,
AU: Schunk, R
EM: schunk@cc.usu.edu
AF: Center For Atmospheric and Space Sciences, Utah State University, Logan, UT 84322,
AU: Eccles, V
EM: vince@spacenv.com
AF: Space Environment Corporation, Spring Greek Parkway, Providence, UT 84332,
AB: Global physics-based models for the high-latitude ionosphere have been developed to such an extent that the large and small ionospheric features during magnetic storms and substorms can be studied. These models, however, require inputs for the magnetospheric forcing, i.e. Magnetospheric convection and particle precipitation. More specifically, for these models to yield reliable results during magnetic storms and substorms, reliable global maps for the high-latitude magnetospheric convection and auroral electron particle precipitation patterns as a function of time are needed. Over the last decades several statistical models for the high-latitude convection and particle precipitation have been developed and used to drive ionospheric models. However, due to the statistical nature of these models, they represent the average characteristics of the true convection and precipitation patten and they are very limited to simulate the effect of magnetic storms and substorms. Recently, with the realization of the Visible Imaging System (VIS) on the Polar Spacecraft, auroral images that yield information of auroral dynamics on a global scale with a spatial resolution of less than 100 km and temporal resolution of ~ 1 minute have become available. These images can be used to calculate reliable global maps for the particle precipitation parameters, electron energy flux and average energies, as a function of time. In this poster we present the preliminary results of our attempt to drive the Ionosphere Forecast Model (IFM) using global maps for the electron precipitation parameters calculated from the corresponding VIS images. In order to elucidate the effect of auroral dynamics on the high-latitude ionosphere, a one-day data set of VIS images during which the aurora was highly active is selected for this study. Then, these images are used to calculate global maps for the electron precipitation parameters using the Lumerzheim model. Next, the maps obtained in the previous step are used as inputs to the IFM and the corresponding plasma parameters are calculated. As a reference against which to compare the ionospheric simulations obtained in the previous step, the same simulations are repeated again but this time using statistical patterns for the particle precipitation parameters obtained from the Hardy statistical model. From the comparison of the two simulations, the impact of the auroral dynamics on the high-latitude ionosphere is elucidated.
DE: 2400 IONOSPHERE (6929)
DE: 2431 Ionosphere/magnetosphere interactions (2736)
DE: 2437 Ionospheric dynamics
DE: 2455 Particle precipitation
DE: 2704 Auroral phenomena (2407)
SC: SPA-Aeronomy [SA]
MN: 2007 Fall Meeting