12:00 〜 12:15
[PEM15-12] High resolution wind observations based on MF radar meteor echo measurements in the northern and southern mid-to-high latitudes
キーワード：下部熱圏、流星風観測、MFレーダー、高時間空間分解能
The MF radar system at Syowa Station (69S, 39E), Antarctic, has been applied to meteor wind observations since 1999 [Tsutsumi and Aso, JGR, 2005] under Japanese Antarctic Research Expedition program. The technique employed is analogous to VHF meteor trail echo measurements, where echoes showing a sudden increase and subsequent exponential decrease of their signal power are detected as meteor echoes and used for further wind analyses. However, because the duration of meteor echoes is proportional to the square of the radio wavelength, the duration of MF (2~3 MHz) meteor echoes is more than 100 times longer than that of usual VHF (~30 MHz) meteor echoes. Many of such long duration MF meteor echoes, often difficult to be distinguished from D/E region ionosphere returns, were not used for the wind measurements although such echoes frequently occupied a significant portion of MF radar echoes.
In the last few years we have redeveloped the MF radar meteor technique at Syowa Station, and now successfully integrated the long duration echoes for wind measurement. Horizontal wind velocities can be estimated with a much improved time resolution of about 10 minutes in the height region of 80-115 km under geomagnetically quiet conditions, and can even be resolved horizontally every 50 km or so within the 10 minutes. Such resolutions are unprecedentedly high as meteor wind measurements [Tsutsumi, SGPESS fall meeting, 2022].
We have recently started seeking a possibility of further applying this technique to MF radars at the northern mid-to-high latitudes, Saura (69N, 16E) and Juliusruh (54N, 13E), routinely operated by Leibniz Institute of Atmospheric Physics. High resolution wind measurements by these radars would especially be beneficial for small scale atmospheric gravity wave studies in the both northern and southern hemispheres.
In the last few years we have redeveloped the MF radar meteor technique at Syowa Station, and now successfully integrated the long duration echoes for wind measurement. Horizontal wind velocities can be estimated with a much improved time resolution of about 10 minutes in the height region of 80-115 km under geomagnetically quiet conditions, and can even be resolved horizontally every 50 km or so within the 10 minutes. Such resolutions are unprecedentedly high as meteor wind measurements [Tsutsumi, SGPESS fall meeting, 2022].
We have recently started seeking a possibility of further applying this technique to MF radars at the northern mid-to-high latitudes, Saura (69N, 16E) and Juliusruh (54N, 13E), routinely operated by Leibniz Institute of Atmospheric Physics. High resolution wind measurements by these radars would especially be beneficial for small scale atmospheric gravity wave studies in the both northern and southern hemispheres.