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Abstract In Vadas et al. (2024,https://doi.org/10.1029/2024ja032521), we modeled the atmospheric gravity waves (GWs) during 11–14 January 2016 using the HIAMCM, and found that the polar vortex jet generates medium to large‐scale, higher‐order GWs in the thermosphere. In this paper, we model the traveling ionospheric disturbances (TIDs) generated by these GWs using the HIAMCM‐SAMI3 and compare with ionospheric observations from ground‐based Global Navigation Satellite System (GNSS) receivers, Incoherent Scatter Radars (ISR) and the Super Dual Auroral Radar Network (SuperDARN). We find that medium to large‐scale TIDs are generated worldwide by the higher‐order GWs from this event. Many of the TIDs over Europe and Asia have concentric ring/arc‐like structure, and most of those over North/South America have planar wave structure and occur during the daytime. Those over North/South America propagate southward and are generated by higher‐order GWs from Europe/Asia which propagate over the Arctic. These latter TIDs can be misidentified as arising from geomagnetic forcing. We find that the higher‐order GWs that propagate to Africa and Brazil from Europe may aid in the formation of equatorial plasma bubbles (EPBs) there. We find that the simulated GWs, TIDs and EPBs agree with EISCAT, PFISR, GNSS, and SuperDARN measurements. We find that the higher‐order GWs are concentrated at N at 200 km, in agreement with GOCE and CHAMP data. Thus the polar vortex jet is important for generating TIDs in the northern winter ionosphere via multi‐step vertical coupling through GWs.
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Coincidental TID Production by Tropospheric Weather during the August 2017 Total Solar Eclipse
It has been proposed [ChimonasH1970], that a total solar eclipse should generate internal Gravity Waves (GWs) that manifest as Traveling Ionospheric Disturbances (TIDs) at ionospheric heights. Zhang et al. [2017] recently reported observations of electron density perturbations trailing the region of maximum obscuration, claiming the results as the first unambiguous evidences for eclipse induced bow waves. We present evidence showing extensive TID activity on two consecutive days, the day of the eclipse and the day before. A particularly intense TID concentric wave field emerged from the background ionosphere five hours before the arrival of the totality, and persisted there throughout the eclipse. The apparent center was located over Iowa/South Dakota region, 300-500 km north from the eclipse path. We examine concurrent observations of tropospheric and ionospheric weather, and find a great spatiotemporal correlation. TID wave parameters do agree with previous observations and models of thunderstorm generated GWs/TIDs, conversely the wave parameters are an order of magnitude off from modeling results for eclipse generated GWs/TIDs.
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- Award ID(s):
- 1743832
- PAR ID:
- 10077195
- Date Published:
- Journal Name:
- Geophysical research letters
- ISSN:
- 1944-8007
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1029/2018GL080239
