Variations of the mean winds and diurnal tides in the mesosphere and lower thermosphere observed by WINDII from 1992 to 1996

摘要: [1] Wind measurements of the satellite-based Wind Imaging Interferometer (WINDII) for Februaries 1992–1996 are used to investigate variations dynamics in mesosphere and lower thermosphere (90–120 km) between 40°S 40°N any possible connection with solar cycle. The period is descending phase cycle 22, that F10.7 flux (2800 MHz) decreases from about 300 70 units 10−22 Wm−2 Hz−1. salient features as follows. (1) Mean zonal winds tropical region upward propagating diurnal tides subtropical regions stronger 1992, 1993 1995 than 1994 1996. (2) mean eastward below 100 km at mid-latitudes February 1992 larger winter hemisphere smaller summer compared those other four years. (3) There significant enhancement tide above particularly hemisphere; amplitude 1996 smallest among five Februaries. (4) has a higher altitude range by 2–4 km. (5) situ thermospheric amplitudes 50 ms−1 8 ms−1.