HR: 0800h
AN: SA31A-0341    [Abstracts]
TI: Polar cap size metrics study at CCMC
AU: * Rastaetter, L
EM: lr@waipio.gsfc.nasa.gov
AF: Code 612.3, NASA GSFC, Greenbelt, MD 20771 United States
AU: Kuznetsova, M M
EM: masha@elbrus.gsfc.nasa.gov
AF: Code 612.3, NASA GSFC, Greenbelt, MD 20771 United States
AU: Hesse, M
EM: mhesse@pop600.gsfc.nasa.gov
AF: Code 612.3, NASA GSFC, Greenbelt, MD 20771 United States
AU: Gombosi, T I
EM: tamas@umich.edu
AF: College of Engineering, University of Michigan, Ann Arbor, MI 48109 United States
AU: Raeder, J
EM: J.Raeder@unh.edu
AF: Space Science Center, University of New Hampshire, Durham, NH 03824 United States
AU: Weimer, D
EM: dweimer@mrcnh.com
AF: Mission Research Corporation, 589 West Hollis Street; Suite 201, Nashua, MH 03062 United States
AB: The Community-Coordinated Modeling Center (CCMC) tests space physics models covering space from the Sun's corona to the Earth's ionosphere and makes them available for researchers through a run-on-request capability. The polar cap size and location as observed by global auroral imagers is used as a basis model to study the performance of global MHD simulation models and statistical models of the auroral ionosphere. With good confidence one can assume that auroral emissions are located within the closed magnetic field lines in a narrow region adjacent to the boundary of the open field line region of the polar cap. In this study we are using imager data from POLAR (FUV) for several events from 1997 to 2000 for which reasonable coverage is available. Simulation runs have been performed using the global magnetospheric models BATSRUS (T. Gombosi et al., U. Michigan) and OpenGGCM (J. Raeder, U. New Hampshire) as well as the Weimer (2000,2005) field-aligned current models (D. Weimer, Mission Research Corp.) fed with upstream solar wind data from the ACE or Geotail satellites. In addition to direct field line tracings available from the 3D MHD model outputs, we use field-aligned currents from both MHD models and the Weimer-2K model to determine the polar cap boundary by using the position of the maximum absolute FAC value in 16 local time sectors. We define skill scores that measure the agreement in the polar cap sizes and location between measurements and models as an example of implementations of metrics to track model performance and apply the analysis to a number of storm event days.
DE: 2407 Auroral ionosphere (2704)
DE: 2431 Ionosphere/magnetosphere interactions (2736)
DE: 2447 Modeling and forecasting
DE: 2475 Polar cap ionosphere
DE: 7954 Magnetic storms (2788)
SC: SPA-Aeronomy [SA]
MN: Fall Meeting 2005