| Abstract: | We present the results of analysis of the data of vertical ionospheric sounding at the Zimenki test site (Nizhny Novgorod). The January and July ionograms are used to plot the dependences of the number of “sickle” type disturbances on the time of the day for the period from 1996 to 1992. A comparison with the scattering in an ionospheric F-layer for the same period is performed. A trend in the time series of the phenomenon observed is recorded. Radiophysical Research Institute, Nizhny Novgorod, Russia. Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 40, No. 12, pp. 1455–1462, December, 1997. |
