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Abstract A new 36.17 MHz all‐sky meteor radar was installed at McMurdo Station Antarctica (77.8°S, 166.7°E) in February 2018 to provide wind measurements in the mesosphere and lower thermosphere (MLT) region (70–120 km). This instrument is the highest latitude meteor radar currently in operation in the southern hemisphere; it joins two other meteor radars within the Antarctic Circle. The radar will provide long‐term continuous wind measurements of the polar region, and contribute to a greater understanding of MLT dynamics. This work describes the radar hardware and its context with other instruments in the region. The paper provides an overview of the spatial and temporal variation in meteor echoes over the observation period of March 2018 through October 2021. It also provides an analysis of the mean winds and solar tides over the first three years of operation; including a description of an observed 12 hr summertime wind oscillation consistent with previously documented observations of a westward propagating 12 hr non‐migrating tide of zonal wavenumber 1.
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Study of a Quasi‐27‐Day Wave in the MLT Region During Recurrent Geomagnetic Storms in Autumn 2018
Abstract A quasi‐27‐day wave (Q27DW) caused by the rotational period of solar radiation is commonly observed in the atmospheric dynamics. In the present study, we report an enhancement of a Q27DW during recurrent geomagnetic storms in the autumn of 2018 based on the zonal wind observations in the mesosphere and lower thermosphere (MLT) region over Beijing (BJ, 40.3°N, 116.2°E). According to our analysis, the solar radiation and the seasonal variation are not important in exciting the observed Q27DW. A 27‐day oscillation exists in both solar wind data andKpindex during the recurrent geomagnetic storms. The Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) temperature and ozone data also reveal a Q27DW signature at 97 km. Using the long‐term observation of BJ meteor radar, two more cases are found during springtime in 2010 and 2018 under the solar quiet condition. Our results indicate that the recurrent geomagnetic storms due to high‐speed solar winds can modulate the temperature and ozone in the MLT region, which is responsible for generating a Q27DW in the MLT zonal winds over BJ. This study suggests that the variation of planetary waves in the MLT neutral winds at mid‐latitude is likely associated with the recurrent geomagnetic storms and high‐speed solar winds.
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- Award ID(s):
- 1744033
- PAR ID:
- 10362076
- Publisher / Repository:
- DOI PREFIX: 10.1029
- Date Published:
- Journal Name:
- Journal of Geophysical Research: Space Physics
- Volume:
- 126
- Issue:
- 4
- ISSN:
- 2169-9380
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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