Effects of Energetic Solar Proton Events of Solar Cycle 23 on Intensity of the Stratospheric Polar Vortex

In this work we continue studying the effects of energetic solar proton events on variations in intensity of the stratospheric polar vortex, which plays an important part in solar-atmospheric relations. It was shown that during strong solar proton events in January 2005 and December 2006, which were accompanied by an increase in the fluxes of particles with energies of more than several hundred MeV, there was a noticeable intensification in zonal western flow in the latitude range of 50 degrees-75 degrees N (the region of the polar vortex formation) at all levels of the stratosphere. A study of the effects of solar proton events with particle energies of >100 MeV which occurred during the 23rd solar cycle (1996-2008) showed that the intensification of the polar vortex associated with the studied events is observed mainly in the western phase of quasi-biennial oscillations of the atmosphere. It was found that an increase in western wind velocity at different stratospheric levels correlates to the greatest extent with changes in ionization rate at altitudes of similar to 50 km. The obtained results allow suggesting that the detected variations in intensity of the stratospheric polar vortex are caused by changes in the radiation-thermal balance of the polar atmosphere, which are due to changes in its chemical composition.