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Abstract Using theHighattitude Interferometer WIND observation balloon and Antarctic Jang Bogo station high latitude conjugate observations of the thermospheric winds we investigate the seasonal and hemispheric differences between the northern and southern hemispheres in June 2018. We found that the summer (northern) hemisphere dayside meridional winds have a double‐hump feature, whereas in the winter (southern) hemisphere the dayside meridional winds have a single hump feature. We attribute that to stronger summer, perhaps, northern hemisphere cusp heating. We also compared the observation with NCAR Thermosphere Ionosphere Electrodynamics General Circulation Model (TIEGCM) model. The TIEGCM reproduced the double‐hump feature because of added cusp heating. The summer hemisphere has stronger anti‐sunward winds. This is the first time we have very high latitude conjugate thermospheric wind observations.
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This content will become publicly available on June 1, 2027
HIWIND Observation of Daytime Thermospheric Winds Over New Zealand and Comparison With Model Simulation
Abstract A balloon borne Fabry Perot interferometer called High altitude Interferometer WIND observation (HIWIND) flew from Wanaka, New Zealand (44.69S, 169.14E) in April 2025 to observe mid‐latitude thermospheric winds in the southern hemisphere for the first time. The HIWIND results were compared with Thermosphere Ionosphere Electrodynamics General Circulation Model (TIEGCM) simulations. The HIWIND observed a stronger poleward (southward) meridional and eastward zonal wind during the daytime compared to the model. The ionospheric density profiles from TIEGCM were compared with those from the COSMIC 2 satellite observations. The peak heights of the ionospheric F2 layer electron density in the observations were lower than those in the model, suggesting that the meridional winds in the real world were stronger than those in the model, which is consistent with the HIWIND and TIEGCM wind comparisons. The source of the weaker simulated winds is not known and is a topic for future studies.
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- Award ID(s):
- 2120511
- PAR ID:
- 10688525
- Publisher / Repository:
- Journal of Geophysical Research: Space Physics
- Date Published:
- Journal Name:
- Journal of Geophysical Research: Space Physics
- Volume:
- 131
- Issue:
- 6
- ISSN:
- 2169-9380
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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