edu.ucar.opensky::articles:42920 UCAR/NCAR - Library OpenSky Support PO Box 3000 Boulder CO 80307-3000 opensky@ucar.edu http://opensky.ucar.edu/ homepage pointOfContact 2025-12-24T17:56:31.742278 ISO 19115-2 Geographic Information - Metadata - Part 2: Extensions for Imagery and Gridded Data ISO 19115-2:2009(E) https://n2t.net/ark:/85065/d7zk5n1w https://doi.org/10.21978/P8D62B https Related Dataset #1 Equivalent Ionospheric Currents (EICs) derived using the Spherical Elementary Currents Systems (SECS) technique at 10 sec Resolution in Geographic Coordinates https://doi.org/10.21978/P8PP8X https Related Dataset #2 Spherical Elementary Current (SEC) Amplitudes derived using the Spherical Elementary Currents Systems (SECS) technique at 10 sec Resolution in Geographic Coordinates https://doi.org/10.5281/zenodo.3765861 https Related Software #1 greglucas/bezpy: First release of bezpy Multi‐scale intense geoelectric and geomagnetic field perturbations observed after an interplanetary magnetic field turning 2025-02-01T00:00:00Z publication https://n2t.net/ark:/85065/d7zk5n1w https://doi.org/10.1029/2024SW004046 Shi, Xueling author Hartinger, M. D. author Zou, Y. author Rigler, E. J. author Weygand, J. M. author Kelbert, A. author Lucas, G. M. author Baker, J. B. H. author Angelopoulos, V. author UCAR/NCAR - Library publisher Intense geoelectric fields during geomagnetic storms generate geomagnetically induced currents in power grids and other infrastructure, necessitating an understanding of their causes, for example, through coordinated space and ground observations. This study investigates localized intense geoelectric ( E ) and geomagnetic ( B ) field perturbations following an Interplanetary Magnetic Field (IMF) turning during a geomagnetic storm on 25 October 2011. Observations from EarthScope magnetotelluric sites in the upper Midwest United States revealed shorter period (1&#160;min) ultra&#8208;low&#8208;frequency (ULF) waves superimposed on longer period (10&#160;min) perturbations in both E and B fields. These sites, located at 19&#160;hr magnetic local time and magnetic latitude, recorded large amplitude E and B perturbations. Ground&#8208;based all&#8208;sky imagers showed auroral brightening with sunward and poleward propagation, while upstream spacecraft linked the perturbations to an IMF turning and solar wind dynamic pressure impulse. The longer&#8208;period E and B field perturbations likely stem from localized ionospheric currents tied to substorm auroral activity post&#8208;IMF turning. The combination of ionospheric currents, ULF waves, and the Earth's varying conductivity produces intense geoelectric fields of 2&#160;V/km in the upper Midwest. A comparison using input data and software compatible with the NOAA/USGS geoelectric field nowcast model revealed its limitations in capturing such events due to the temporal and spatial resolution of the underlying data. Using 1&#8208;s geomagnetic field data can improve geoelectric field models by capturing short&#8208;period and large spatial scale waves, although localized magnetic perturbations remain underestimated due to insufficient ground magnetometer density. 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 <span style="font-family:Arial;font-size:10pt;font-style:normal;" data-sheets-root="1">Copyright author(s). This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.</span> None eng geoscientificInformation