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Abstract The space hurricane is a three‐dimensional magnetic vortex structure with strong flow shears and electron precipitation in the polar cap. This study investigates for the first time how a space hurricane disturbs the polar thermosphere. During the formation and development of the space hurricane, the directional reversal of the horizontal neutral wind and the plasma convection will both be relocated from the poleward auroral oval boundary to the edge of the space hurricane, but the neutral wind responds slower compared to the plasma convection. Strong flow shears in the space hurricane causes enhanced Joule heating in the polar cap, which heats the thermosphere and triggers Atmospheric Gravity Waves (AGWs). Statistical results reveal that significant AGWs mainly are located on the dawnside of the space hurricane, suggesting that the space hurricane plays a significant role in ion‐neutral coupling and generation of polar cap AGWs.
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This content will become publicly available on April 28, 2026
How Do Space Hurricanes Disturb the Polar Thermosphere: A Statistical Survey
Abstract The space hurricane is a polar cap auroral structure with strong flow shears and intense particle precipitation that can disturb the thermosphere under quiet geomagnetic conditions. Here the statistical characteristics of this interaction are surveyed using data from the Defense Meteorological Satellite Program and Gravity Field and Steady‐State Ocean Circulation Explorer satellites. The results confirm that space hurricanes modify the ion and neutral circulation in the polar cap through enhanced electric fields. Local precipitation, particularly >500 eV electrons, which raises the Pedersen conductance, leads to enhanced Joule heating and the generation of gravity waves. Electric fields play a leading role on the dawn side of the space hurricane. Gravity waves are also mainly located on the dawnside of the space hurricane, with a maximum vertical wind of 37 m/s and a 17% neutral density disturbance. These findings augment our awareness of magnetosphere‐polar ionosphere‐thermosphere coupling under quiet northward IMF conditions.
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- Award ID(s):
- 2055192
- PAR ID:
- 10639756
- Publisher / Repository:
- Journal of Geophysical Rsearch
- Date Published:
- Journal Name:
- Geophysical Research Letters
- Volume:
- 52
- Issue:
- 8
- ISSN:
- 0094-8276
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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