Variations of Stratospheric Ozone at the Time of Extremely High Solar Activity

Abstract

Many investigators have found the 5–7% trend, related with 27-day and 11-year solar activity cycles by means of the analyses of the Total Ozone Content (TOC) data. In this paper we have investigated the possible TOC variations at the time of extremely high solar activity when F10,7 is about 350. Such unobserved values could be reached (in the future or in the past) at the time of supercenturial solar cycle. From the climatic point of view this high activity could influence the climate through the stratospheric ozone. For this purpose we have constructed a model of solar flux in the region 1216–3300 A, based on the ratio of Lα.(max/min) equal to 2 given by Lean, 1982 (ref. in WMO, 1985). Mainly experimental data has been used. The variation of stratospheric ozone has been calculated by means of a stationary photochemical model. The maximal value of F10 7 has been taken as 350. The main results from the modelling are: 1) 5% increase of TOC from minimum to maximum solar activity (F10,7 100–200) is due basically to the photochemistry; 2) At F10,7 equal to 350, the calculated photochemical increase of TOC is about 9%; 3) In all ’diapason of data for F10,7 (from 100 to 350) the increase of TOC follows the law ∆TOC~ (∆ F200)1/2, where ∆ F200 is the flux of wavelength of 2000 A; 4) The existing reverse negative interrelations between the TOC and temperature could only decrease the ozone growth. The main conclusion is that the extremely high solar activity cannot dramatically influence the behavior of stratospheric ozone and is not compatible with anthropogenious factors.