%AHartinger, M. [Bradley Department of Electrical and Computer Engineering Virginia Polytechnic Institute and State University Blacksburg Virginia USA, National Institute of Aerospace Hampton Virginia USA]%AHartinger, M. [Bradley Department of Electrical and Computer Engineering; Virginia Polytechnic Institute and State University; Blacksburg Virginia USA; National Institute of Aerospace; Hampton Virginia USA]%AXu, Z. [Bradley Department of Electrical and Computer Engineering Virginia Polytechnic Institute and State University Blacksburg Virginia USA, National Institute of Aerospace Hampton Virginia USA]%AXu, Z. [Bradley Department of Electrical and Computer Engineering; Virginia Polytechnic Institute and State University; Blacksburg Virginia USA; National Institute of Aerospace; Hampton Virginia USA]%AClauer, C. [Bradley Department of Electrical and Computer Engineering Virginia Polytechnic Institute and State University Blacksburg Virginia USA, National Institute of Aerospace Hampton Virginia USA]%AClauer, C. [Bradley Department of Electrical and Computer Engineering; Virginia Polytechnic Institute and State University; Blacksburg Virginia USA; National Institute of Aerospace; Hampton Virginia USA]%AYu, Y. [School of Space and Environment Beihang University Beijing China]%AYu, Y. [School of Space and Environment; Beihang University; Beijing China]%AWeimer, D. [Bradley Department of Electrical and Computer Engineering; Virginia Polytechnic Institute and State University; Blacksburg Virginia USA; National Institute of Aerospace; Hampton Virginia USA]%AWeimer, D. [Bradley Department of Electrical and Computer Engineering Virginia Polytechnic Institute and State University Blacksburg Virginia USA, National Institute of Aerospace Hampton Virginia USA]%AKim, H. [Center for Solar-Terrestrial Research; New Jersey Institute of Technology; Newark New Jersey USA]%AKim, H. [Center for Solar‐Terrestrial Research New Jersey Institute of Technology Newark New Jersey USA]%APilipenko, V. [Space Research Institute; Moscow Russia]%APilipenko, V. [Space Research Institute Moscow Russia]%AWelling, D. [Climate and Space Sciences and Engineering Department University of Michigan Ann Arbor Michigan USA]%AWelling, D. [Climate and Space Sciences and Engineering Department; University of Michigan; Ann Arbor Michigan USA]%ABehlke, R. [National Space Institute Technical University of Denmark Lyngby Denmark]%ABehlke, R. [National Space Institute; Technical University of Denmark; Lyngby Denmark]%AWiller, A. [National Space Institute Technical University of Denmark Lyngby Denmark]%AWiller, A. [National Space Institute; Technical University of Denmark; Lyngby Denmark]%BJournal Name: Journal of Geophysical Research: Space Physics; Journal Volume: 122; Journal Issue: 7; Related Information: CHORUS Timestamp: 2023-09-01 18:25:57 %D2017%IDOI PREFIX: 10.1029 %JJournal Name: Journal of Geophysical Research: Space Physics; Journal Volume: 122; Journal Issue: 7; Related Information: CHORUS Timestamp: 2023-09-01 18:25:57 %K %MOSTI ID: 10037611 %PMedium: X %TAssociating ground magnetometer observations with current or voltage generators %XAbstract

A circuit analogy for magnetosphere‐ionosphere current systems has two extremes for drivers of ionospheric currents: ionospheric electric fields/voltages constant while current/conductivity vary—the “voltage generator”—and current constant while electric field/conductivity vary—the “current generator.” Statistical studies of ground magnetometer observations associated with dayside Transient High Latitude Current Systems (THLCS) driven by similar mechanisms find contradictory results using this paradigm: some studies associate THLCS with voltage generators, others with current generators. We argue that most of this contradiction arises from two assumptions used to interpret ground magnetometer observations: (1) measurements made at fixed position relative to the THLCS field‐aligned current and (2) negligible auroral precipitation contributions to ionospheric conductivity. We use observations and simulations to illustrate how these two assumptions substantially alter expectations for magnetic perturbations associated with either a current or a voltage generator. Our results demonstrate that before interpreting ground magnetometer observations of THLCS in the context of current/voltage generators, the location of a ground magnetometer station relative to the THLCS field‐aligned current and the location of any auroral zone conductivity enhancements need to be taken into account.

%0Journal Article