Winter North Atlantic Oscillations Driven by Variations in Total Solar Irradiance

Abstract

The solar influence on long-term climatic processes of Earth has been studied with the use of long-term series of historical reconstructions of Total Solar Irradiation (TSI) based on telescopic observations since 1610 and reconstructions of the complex climatic phenomenon of the North Atlantic Oscillation (NAO) based on its manifestations in various biological systems of the region. Partial Fourier Approximation (PFA) and Singular Spectrum Analysis (SSA) are used for joint analysis of these time series. The fluctuations of the TSI and NAO indices have a number of common, but antiphase, cycles, especially in the low frequency band with periodicity 60–80 years. The weak TSI variations (0.01–0.03% of TSI average) almost completely determine all NAO variations with periods of more than 20 years. The main Schwabe solar cycle manifests itself weakly and unstably in the NAO.