First observation of mesospheric and thermospheric winds by a Fabry-Perot interferometer in China

A Fabry-Perot interferometer, funded by the Meridian Project in China, was deployed at the Xinglong station (40.2 degrees N, 117.4 degrees E) of the National Astronomical Observatories in Hebei Province, China. The instrument has been operating since April 2010, measuring mesospheric and thermospheric winds. The first observational data of winds at three heights in the mesosphere and thermosphere were analyzed, demonstrating the capacity of this instrument to aid basic scientific research. The wavelengths of three airglow emissions were OH892.0, OI 557.7, and OI 630.0 nm, which corresponded to heights of 87, 98, and 250 km, respectively. Three 38-day data sets of horizontal winds, from April 5, 2010 to May 12, 2010, show clear day-to-day variations at the same height. The minimum and maximum meridional winds at heights of 87, 98, and 250 km were -16.5 to 8.7 m/s, -24.4 to 15.9 m/s, and -43.6 to 1.5 m/s. Measurements of zonal winds were -5.4 to 7.6 m/s, 2.3 to 23.0 m/s, and -22.6 to 49.3 m/s. The average data from the observations was consistent with the data from HWM93. The wind data at heights of 87 and 98 km suggest a semi-diurnal oscillation, clearly consistent with HWM93 results. Conversely there was a clear discrepancy between the observations and the model at 250 km. In general, this Fabry-Perot interferometer is a useful ground-based instrument for measuring mesospheric and thermospheric winds at middle latitudes.