edu.ucar.opensky::articles:17230 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-26T14:51:11.563343 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.org/ark:/85065/d7bp0434 Saturation of transpolar potential for large Y component interplanetary magnetic field 2010-06-03T00:00:00Z publication https://n2t.org/ark:/85065/d7bp0434 https://doi.org/10.1029/2009JA015119 Mitchell, E. author Lopez, R. author Bruntz, R. author Wiltberger, Michael author Lyon, J. author Allen, R. author Cockrell, S. author Whittlesey, P. author UCAR/NCAR - Library publisher This study examines the response of the transpolar potential to a large Y component interplanetary magnetic field (IMF By). The transpolar potential responds nonlinearly and saturates for large IMF By in the Lyon-Fedder-Mobarry (LFM) global MHD simulation, just as it does for large southward IMF (-Bz). Data from Defense Meteorological Satellite Program (DMSP) satellites and Assimilative Mapping of Ionospheric Electrodynamics (AMIE) results confirm the saturation of the transpolar potential during large IMF By. The magnitude of the saturated transpolar potential is significantly smaller for large IMF By than for large negative IMF Bz. This indicates that transpolar potential saturation does not depend on the strength of the Region 1 current. However, the magnitude of the IMF at which the transpolar potential becomes nonlinear and begins to exhibit saturation behavior is the same for large By as it is for large Bz. Furthermore, when the IMF (By or Bz) reaches the value that produces saturation, the magnetosheath becomes magnetically dominated, with β < 1. This suggests that the saturation of the transpolar potential is related to a change in the force balance in the magnetosheath from a plasma-pressure-dominated magnetosheath to a magnetically-dominated magnetosheath. 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 Copyright 2010 American Geophysical Union. None eng geoscientificInformation