The "Sun-climate" relationship : III. The solar flares, north-south sunspot arrea asymmetry and climate

TL;DR

This paper investigates the complex relationship between solar activity, including solar flares and cosmic rays, and climate variations over the last 150 years, emphasizing the role of solar energetic particles and hemispheric asymmetry.

Contribution

It provides new evidence that solar energetic particles significantly influence climate, highlighting the importance of solar activity asymmetry in climate effects beyond irradiance and cosmic rays.

Findings

Solar energetic particles contribute to climate cooling during high solar activity epochs.

Subcenturial temperature oscillations (~60 years) correlate with solar activity cycles.

Hemispheric asymmetry of solar activity modulates the strength of solar influence on climate.

Abstract

In this last Paper III additional evidences that the solar high energetic particles radiation with energies higher as 100 MeV (the solar cosmic rays SCR) is an very important component for the "Sun- climate" relationship are given (see also Paper I and II). The total solar irradiance (TSI) and the galactic cosmic rays (GCR) variations given an integral climate effect of cooling in sunspot minima and warming in the sunspot maxima. Unlike the both ones the powerful solar corpuscular events plays a cooling climate role during the epochs of their heigh levels. By this one subcenturial global and regional temperature quasi- cyclic changes by duration of approximately 60 years could be track during the last 150 years of instrumental climate observations . It has been also evided in the paper that this subcenturial oscilation is very important in the Group sunspot number (GSN) data series since the Maunder minimum up to the end of 20th century. Thus the solar erruptive activity effect make the total "Sun -climate" relationship essentially more complicated as it could be follow when only the TSI and GCR variations are taken into account. In this light the climate warming tendency after AD 1975 is rather by a natural as by an antropogenic origin. Most probably the last one is very close related to the general downward tendency of erruptive solar events which is superimposed over the high long term TSI levels during the last three decades (AD 1975-2007). It is evided, that the efficiency of the solar corpuscular activuty over the climate is strongly depended by the "north-south" asymmetry of the solar activity centers (as a proxy the sunspots area north-south asymmetry index A is used there). The climate cooling effect in the Northern hemisphere is most powerful during the epochs of positive values of A.