edu.ucar.opensky::articles:17406 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-26T15:22:57.135884 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.org/ark:/85065/d7cr5vnw Geotail and LFM comparisons of plasma sheet climatology: 1. Average values 2008-04-18T00:00:00Z publication https://n2t.org/ark:/85065/d7cr5vnw https://doi.org/10.1029/2007JA012611 Guild, T. author Spence, H. author Kepko, E. author Merkin, V. author Lyon, J. author Wiltberger, Michael author Goodrich, C. author UCAR/NCAR - Library publisher We compare the statistics of central plasma sheet properties from 6 years of Geotail observations with 2 months of Lyon-Fedder-Mobarry (LFM) global MHD simulations. This statistical validation effort represents an inherently new method of systematically characterizing and quantifying global MHD model performance. For our comparison, we identify the central plasma sheet in the observations and simulation by identical criteria and select the simulation interval to ensure statistically similar distributions of solar wind conditions in both studies. After verifying our plasma sheet selection by inspecting the magnetic signatures of both studies, we compare the resultant number densities, thermal pressures, thermal energies, and bulk flows as functions of position across the equatorial plane. We find that the LFM model successfully reproduces the gross features of the global plasma sheet in a statistical sense. However, our comparison also reveals certain systematic discrepancies between the model and the observations. The LFM predicts a plasma sheet which is too dense, too cool, and exhibits faster globally averaged bulk flows than the observed plasma sheet. By quantifying the LFM overestimate of ionospheric transpolar potential and showing that ÎŚ PC correlates with plasma sheet flow speed, we demonstrate that 15% of the plasma sheet velocity discrepancy is reflected in a ÎŚ PC overestimate. This statistical validation effort represents an essential first step toward the rigorous, quantitative evaluation of a global MHD model in the plasma sheet. UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact PDF Text theme Resource Type 2016-01-01T00:00:00Z publication An edited version of this paper was published by the American Geophysical Union. Copyright 2008 AGU. None eng geoscientificInformation