| Abstrakt: |
Abstract: The seasonal variation of gravity wave activity at altitudes around 95 km is investigated using digital measurements of low-frequency nighttime radiowave absorption at Průhonice (50°N, 15°E) between 1989 and 1993. The analysis of 5 years of data allows two conclusions to be drawn: (1) under high solar activity conditions, there is no clearly detectable seasonal variation of gravity wave activity; (2) under medium solar activity conditions (1992, 1993), there is a tendency to a pronounced summer maximum. |
