Atmospheric-ionospheric effects of the solar eclipse of May 31, 2003, in Kharkov

摘要

Results of studying the response of the near-Earth atmosphere and ionosphere to the partial (73%) solar eclipse of May 31, 2003, which was observed after the sunrise against a background of the magnetic storm recovery, are presented. It has been found out that the daytime atmospheric conditions changed into the night-time conditions for similar to 2-3 h during the eclipse. A decrease in the ionizing solar radiation flux during the eclipse results in a change in the balance of plasma production, loss, and transfer, which causes an acceleration of downward plasma diffusion from the upper ionosphere compensating for the loss of plasma. During the phase of eclipse maximum, the electron density at the F2layer maximum (NmF2) decreased by 9-17% because the process of plasma loss was predominant, the electron temperature (T,) became approximately 500 K lower, and the amplitude of a decrease in the ion temperature (T-i) increased with increasing altitude (by 300 K at an altitude of 700 km) with a delay relative to the eclipse onset. The eclipse caused a 10-20% increase in the fractional number density of hydrogen ions in the phase of eclipse maximum at altitudes of 1100-1500 kin. The effects of the magnetic disturbance and solar flare, as well as the specific behavior of the near-Earth atmosphere and ionosphere during the sunrise, which were superimposed on the response of the Earth's space environment to the solar eclipse, have also been studied.