The sunspot cycle, the QBO, and the total ozone over Northeastern Europe: a connection through the dynamics of stratospheric circulation

Abstract

Abstract. The interaction between the factors of the quasi-biennial oscillation (QBO) and the 11-year solar cycle is considered as an separate factor in¯uencing the interannual January±March variations of total ozone over Northeastern Europe. Linear correlation analysis and the running correlation method are used to examine possible connections between ozone and solar activity at simultaneous moment the QBO phase. Statistically signi®cant correlations between the variations of total ozone in February and, partially, in March, and the sunspot numbers during the dierent phases of QBO are found. The running correlation method between the ozone and the equatorial zonal wind demonstrates a clear modulation of 11-y solar signal for February and March. Modulation is clearer if the QBO phases are de®ned at the level of 50 hPa rather than at 30 hPa. The same statistical analyses are conducted also for possible connections between the index of stratospheric circulation g 1 and sunspot numbers considering the QBO phase. Statistically signi®cant connections are found for February. The running correlations between the index g 1 and the equatorial zonal wind show the clear modulation of 11-y solar signal for February and March. Based on the obtained correlations between the interannual variations of ozone and index g 1 , it may be concluded that a connection between solar cycle ± QBO ± ozone occurs through the dynamics of stratospheric circulation.

The equatorial stratospheric QBO and geomagnetic activity

“…Combining our results with those of Labitzke and Van Loon (1988, Soukharev (1997Soukharev ( , 1999 and Varotsos (1989) concerning ozone content and temperature in the Northern Polar stratosphere, it could be said that during maximum solar activity, higher geomagnetic activity and UV levels coincide with the easterly phase of the QBO together with lower temperatures and less ozone in the Northern Polar cap, while the westerly phase coincide with lower geomagnetic activity and UV levels together with stratospheric warming and more ozone in the Northern Polar cap. During minimum solar activity levels this relationship is reversed.…”

The quasi-decadal modulation of running correlations involving the QBO

“…Troshichev and Gabis (1998), Soukharev and Hood (2001) and Gabis and Troshichev (2004) showed that the UV irradiance undergoes quasibiennial periodicity which may have an effect on the stratospheric QBO. After this idea, Elias and Zossi de Artigas (2003) estimated the running correlation between the QBO signal in the 10.7 cm solar radio emission, F10.7, and the equatorial stratospheric QBO and found a quasi-decadal variation in the correlation coefficient series similar to what Kodera (1993), Soukharev (1997Soukharev ( , 1999 and Salby and Callaghan (2004) found.…”

“…The running correlation between the QBO and certain atmospheric and solar parameters, observed by some authors (Kodera, 1993;Soukharev, 1997Soukharev, , 1999Elias and Zossi de Artigas, 2003;Salby and Callaghan, 2004;Zossi de Artigas and Elias, 2005), present a quasi-decadal modulation. As an example, we present in this section some results using experimental time series.…”

“…2. This data analysis, using stratosphere parameters, is discussed in detail by Kodera (1993), Soukharev (1997Soukharev ( , 1999 and Salby and Callaghan (2004). The quasi-decadal variation in the running correlation series would imply that during maximum solar activity levels higher temperature and geopotential heights occur during the westerly phase of the QBO and lower temperature and geopotential heights take place during the easterly phase of the QBO.…”

“…This interaction has been analyzed mainly through the possible connection between atmospheric parameters and solar activity, grouping data according to the QBO phases or through the running correlation method. Regarding the last method, Kodera (1993) estimated the running correlation of the QBO with the North Polar stratospheric temperature, Soukharev (1997Soukharev ( , 1999, with total ozone content over Northeastern European stations, and Salby and Callaghan (2004) with wintertime tendency. They all obtained running correlation coefficients with a clear quasidecadal modulation.…”