Traveling Ionospheric Disturbances in the Vicinity of Storm‐Enhanced Density at Midlatitudes
Name
JGR Space Physics - 2022 - Zhang - Traveling Ionospheric Disturbances in the Vicinity of Storm‐Enhanced Density at.pdf
Description
Published version
Size
11.89 MB
Format
Adobe PDF
Checksum (MD5)
34fea8186c0a256ea99b0273c5409b2d
Author(s)
Zhang, Shun‐Rong
Nishimura, Yukitoshi
Erickson, Philip J
Aa, Ercha
Kil, Hyosub
Deng, Yue
Thomas, Evan G
Rideout, William
Coster, Anthea J
Kerr, Robert
Date Issued
August 2022
Journal
Journal of Geophysical Research: Space Physics
Publisher
American Geophysical Union (AGU)
Citation
Zhang, Shun‐Rong, Nishimura, Yukitoshi, Erickson, Philip J, Aa, Ercha, Kil, Hyosub et al. 2022. "Traveling Ionospheric Disturbances in the Vicinity of Storm‐Enhanced Density at Midlatitudes." Journal of Geophysical Research: Space Physics, 127 (8).
Version
Final published version
Abstract
This study provides first storm time observations of the westward-propagating medium-scale traveling ionospheric disturbances (MSTIDs), particularly, associated with characteristic subauroral storm time features, storm-enhanced density (SED), subauroral polarization stream (SAPS), and enhanced thermospheric westward winds over the continental US. In the four recent (2017-2019) geomagnetic storm cases examined in this study (i.e., 2018-08-25/26, 2017-09-07/08, 2017-05-27/28, and 2016-02-02/03 with minimum SYM-H index -206, -146, -142, and -58 nT, respectively), MSTIDs were observed from dusk-to-midnight local times predominately during the intervals of interplanetary magnetic field (IMF) Bz stably southward. Multiple wavefronts of the TIDs were elongated NW-SE, 2°-3° longitude apart, and southwestward propagated at a range of zonal phase speeds between 100 and 300 m/s. These TIDs initiated in the northeastern US and intensified or developed in the central US with either the coincident SED structure (especially the SED basis region) or concurrent small electron density patches adjacent to the SED. Observations also indicate coincident intense storm time electric fields associated with the magnetosphere-ionosphere-thermosphere coupling electrodynamics at subauroral latitudes (such as SAPS) as well as enhanced thermospheric westward winds. We speculate that these electric fields trigger plasma instability (with large growth rates) and MSTIDs. These electrified MSTIDs propagated westward along with the background westward ion flow which resulted from the disturbance westward wind dynamo and/or SAPS.
MIT Department
Haystack Observatory
Terms of Use
Creative Commons Attribution-NonCommercial-NoDerivs License
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1029/2022ja030429
