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Title: Medium-scale traveling ionospheric disturbances created by primary gravity waves generated by a winter storm
This study explores the meteorological source and vertical propagation of gravity waves (GWs) that drive daytime traveling ionospheric disturbances (TIDs), using the specified dynamics version of the SD-WACCM-X (Whole Atmosphere Community Climate Model with thermosphere-ionosphere eXtension) and the SAMI3 (Sami3 is Also a Model of the Ionosphere) simulations driven by SD-WACCM-X neutral wind and composition. A cold weather front moved over the northern-central USA (90–100°W, 35–45°N) during the daytime of 20 October 2020, with strong upward airflow. GWs with ~500–700 km horizontal wavelengths propagated southward and northward in the thermosphere over the north-central USA. Also, the perturbations were coherent from the surface to the thermosphere; therefore, the GWs were likely generated by vertical acceleration associated with the cold front over Minnesota and South Dakota. The convectively generated GWs had almost infinite vertical wavelength below ~100 km due to being evanescent. This implies that the GWs tunneled through their evanescent region in the middle atmosphere (where a squared vertical wavenumber is equal to or smaller than 0) and became freely propagating in the thermosphere and ionosphere. Medium-scale TIDs (MSTIDs) also propagated southward with the GWs, suggesting that the convectively generated GWs created MSTIDs.  more » « less
Award ID(s):
2411429
PAR ID:
10575053
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
EDP Sciences
Date Published:
Journal Name:
Journal of Space Weather and Space Climate
Volume:
14
ISSN:
2115-7251
Page Range / eLocation ID:
38
Subject(s) / Keyword(s):
gravity waves MSTIDs
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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