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Danilov, A. D.

Publications and source records attributed to Danilov, A. D..

At least 19 records

General overview of the solar activity effects on the lower ionosphere

Solar activity influences the ionospheric D region. That influence manifests itself both in the form of various solar induced disturbances and in the form of the D region dependence on solar activity parameters (UV-flux, interplanetary magnetic field, solar wind etc.) in quiet conditions. Relationship between solar activity and meteorological control of the D region behavior is considered in detail and examples of strong variations of aeronomical parameters due to solar or meteorological events are given.

Danilov, A. D.

Progress in D-region studies during MAP

During MAP, active studies of the ionospheric D region were performed. The most interesting and fruitful were those in which variations of D region parameters and of the dynamical regime of the middle atmosphere were intercompared. As a result, the general picture of the D region behavior became much clearer than before. It appears that the D region is strongly influenced by dissipation of internal gravity waves which come from below and are destroyed at altitudes 80 to 100 km. This influence is much stronger in winter than in summer due to the filtering effect of the stratospheric circulation on these waves. As a result, strong day-to-day variability of the D region in winter and relative stability in summer, is now clear.

Danilov, A. D.

Middle Atmosphere Temperature and Dynamics as Revealed from D-region Observations

The concept of so-called meteorological control of the ionospheric D-region is presently undergoing development. According to this concept the electron concentration in this region is governed not only by solar and geomagnetic parameters but strongly depends on the temperature and dynamical regime of the mesosphere and stratosphere. How this connection between D-region and meteorological parameters can be used to obtain some information about middle atmosphere temperature and dynamics is examined. The essential points of the meteorological control concept are reviewed and the influence of turbulence on nitric oxide distribution and thus the ion production rate is discussed.

Danilov, A. D.

Soviet National Middle Atmosphere Program

Soviet national MAP program comprises seven projects: lower thermosphere (structure and dynamics); high latitude energetic sources and their effect on the structure and dynamics of the upper atmosphere under conditions of the polar night; climate of the stratosphere and mesosphere (effects of various energetic sources on its formation); winter variability in the lower ionosphere; noctilucent clouds (climatology, dynamics, nature, and genesis); wave processes and structure and dynamics of the stratosphere and mesosphere; and dynamics of the ozone layer.

Danilov, A. D.