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Abstract

The effects of the 11-year, quasi-biennial, and 27-day cycles of solar activity on dynamical processes in the atmosphere are studied using empirical data and results of numerical model calculations. Estimates of changes during the 11-year solar cycle in the wind velocity, potential vorticity, geopotential and its large-scale zonal harmonics are obtained using the ERA-Interim reanalysis data. Features of the response of these atmospheric parameters to the solar cycle in some areas of the atmosphere are revealed for a whole year and depending on season. The results point to the existence of a reliable statistical relation of large-scale dynamical and thermodynamic processes in the troposphere and stratosphere to the 11-year solar cycle. Based on the results of 200-year measurements, the phase synchronization of decadal variations of the North Atlantic Oscillation index with the 11-year solar cycle have been found within time intervals alternating with 45-50-year periodicity. According to the ERA-Interim data, the quasi-biennial oscillation in the equatorial stratospheric zonal wind velocity is phase-synchronized at the stratopause level (∼50 km) with the quasi-biennial variations of UV solar radiation. The proposed reason of the synchronization may be the the inhomogeneous heating of this layer due to the absorption of UV solar radiation by ozone, the meridional gradient of which changes in harmony with the quasi-biennial solar variations. The effect of the 27-day solar cycle on the characteristics of large-scale zonal wave harmonics of the geopotential in the Northern Hemisphere is analyzed using results of calculations by a 3-dimensional chemistry-climatic model. Noticeable correlations of the amplitude of the planetary wave components in winter in the Northern Hemisphere with the 27-day solar cycle have been found. The strongest response is obtained for perturbations with wave number 1 in the middle and high latitudes of the Northern Hemisphere. © Published under licence by IOP Publishing Ltd.