Observation of 6.5-day waves in the MLT region over Wuhan

【摘要】：正In this paper,the 6.5-day planetary waves over Wuhan(30.5°N,114.3°E) were investigated on the basis of the meteor radar measurements within 78-98 km height region during February 2002-December 2005.The observations show that 6.5-day waves have a prominent seasonal variability and have larger amplitudes at equinoxes than at solstices.We also found that intensive waves occur mostly between 84 and 98 km,and the zonal components of 6.5-day waves are a little larger than its meridional components on average.The main periods of 6.5-day waves are near 6-7 days in spring/winter season and 5-7 days(even extend to 8 days) in autumn months.However,these waves exhibit a downward progression when the amplitude is large.Robust wave events occur basically in eastward background winds.During the 4-year interval, the strongest waves were found in Apri--May of 2003 and 2004.