Structural changes in lower ionosphere wind trends at midlatitudes

[摘要] Long-term variability of the mesosphere/lower thermosphere (lower E regionionosphere) since 1970 has been analyzed using wind data series obtained atCollm (52° N, 15° E) using the LF drift method and at Obninsk (55° N, 37° E)applying VHF meteor radar. Applying piecewise linear trendanalysis with a priori unknown number and positions of breakpoints showsthat trend models with breakpoints are generally to be preferred againststraight lines. There is a strong indication for a change of trends in windparameters around 1975–1980. Similar changes are also found in the loweratmosphere, e.g., in tropospheric temperatures. This indicates a couplingbetween atmospheric layers at time scales of decades.

[学科分类] 电子、光学、磁材料