Relation of the F2 region to the parameters of the stratosphere: Comparison of two solar cycles

The results concerning the relation of the stratosphere and ionosphere, obtained on the basis of the data of the 1979–1989 solar cycle, are compared to the data of the following solar cycle. It is shown that all the regularities of the behavior of the correlation coefficient r(h, fo) between the stratospheric parameter h(100) and the critical frequency fo F2 found for the 1980s are also true for the 1990s. Moreover, it turns out that the r(h, fo) dependence on solar activity is similar within both solar cycles.