HR: 1400h
AN: SA33A-11    [Abstracts]
TI: Quantifying the High-Latitude Magnetosphere-Ionosphere Energy Transfer for General Circulation Models
AU: Maute, A I
EM: maute@ucar.edu
AF: NCAR High Altitude Observatory, PO Box 3000, Boulder, CO 80305, United States
AU: * Richmond, A D
EM: richmond@ucar.edu
AF: NCAR High Altitude Observatory, PO Box 3000, Boulder, CO 80305, United States
AB: Electric fields and currents associated with magnetosphere-ionosphere interactions, along with auroral particle precipitation, are an important source of thermospheric energy and momentum, affecting the global thermospheric temperature, density, composition, and winds. The effects are strong during and after magnetic storms, but the thermosphere is also influenced during quiet times. Thermosphere-ionosphere general-circulation models (GCMs) have been able to produce the general features of the thermospheric response to magnetosphere-ionosphere coupling, but for predictive purposes the quantitative spatial and temporal distribution of the energy inputs needed for the GCMs is inadequately known. Our goal is therefore to develop empirical models to quantify the distribution of magnetosphere-ionosphere energy transfer as a function of geophysical indexes, by analyzing Dynamic Explorer-2 (DE2) data. As a first step we developed simplified empirical models of the Poynting flux and of the electric and magnetic potentials that depend on the magnitude and orientation of the interplanetary magnetic field, as well as on season, latitude, and magnetic local time. These simplified models of the high-latitude electrodynamics are being implemented to specify energy inputs to a thermosphere-ionosphere GCM. A second step of our work will be to characterize the spatial and temporal properties of the variability of the energy input about the averages represented by these empirical models, in order to develop representations for GCMs of the effects of small-scale electrodynamic structures.
DE: 0358 Thermosphere: energy deposition (3369)
DE: 2409 Current systems (2721)
DE: 2411 Electric fields (2712)
DE: 2431 Ionosphere/magnetosphere interactions (2736)
DE: 3369 Thermospheric dynamics (0358)
SC: SPA-Aeronomy [SA]
MN: 2007 Joint Assembly