Global planetary ionization maps in regener-photzer cosmic ray maximum for gle 65, 66 and 67 - associated with geomagnetic superstorms of 29-31 october 2003

An extreme solar activity was observed in late October - beginning of November 2003. During this period a sequence of three GLEs − on 28 October (GLE 65), 29 October (GLE 66) and on 2 November 2003 (GLE 67) was produced, accordingly observed by the global neutron monitor network. In this work, for the first time are studied the Induced Atmospheric Ionization (IAI) effects of the three consecutive GLEs − the so-called Halloween events. They are associated with the strongest geomagnetic storms (in the last 30 years) of 29-31 October 2003 with maximal Ap-index 204. Therefore, there were intense Forbush effects. The ion production rates during the events are evaluated on the basis of full target Monte Carlo simulation model using recently derived GLE particles spectra. The ion production rate profiles (0 - 40 km) in the atmosphere during the investigated sequence of the Halloween GLE events are calculated for regions with cut-off rigidities of 1 GV and 2 GV. The integrated over 24h ionization effect in the region of Regener-Pfotzer maximum is accordingly assessed. There are made global planetary maps of Induced Atmospheric Ionization in the region of Regener-Photzer maximum due to cosmic rays (CRs) of galactic and solar origin during the Ground Level Enhancements GLE 65, 66 and 67. IAI is one of the main drivers of the possible effect of CR particles on atmospheric physics and chemistry. The Induced Atmospheric Ionization by CRs, which can be considerably enhanced during solar proton events, was extensively discussed over the last decade. In most of the recent models IAI plays a key role on the physics and chemistry of the atmosphere, specifically on minor constituents, for example the ozone which to a great extent determines the meteorological constant in climate models. It was known that the contribution of galactic CR particles to ion production in the atmosphere is nearly constant, slightly influenced by the solar activity. On the other hand, the relativistic solar particles could produce a significant excess of ion pair production, particularly over polar caps. The investigation of ionization atmospheric effects due to the sequence of the three Ground Level Enhancements GLE 65, 66 and 67 on October-November 2003 in conditions of strong Forbusch decreases give an unique opportunity to study the solar impact effects on enhanced manner and extended time scale.