Possible effects of galactic cosmic ray flux and low-cloud amounts on global surface temperature

Abstract

The solar variations, solar–climate interactions, and the mechanisms controlling the response of Earth’s climate system are important to understand the effect of solar variability on climate change. The solar magnetic field is directly/indirectly disturbing the interplanetary space, the ionosphere, the magnetosphere, and even the atmosphere. To investigate the contribution of varying galactic cosmic flux, the role of sunspot number (Rz), galactic cosmic ray (GCR) rates, cloud condensation nuclei (CCN), total solar irradiance (TSI), $$\hbox {CO}_{{2}}$$ concentration and the global surface temperature (GST) is examined. The variations of TSI can partially explain the global increase in temperature, and it accounts for about $$0.5^{\circ }\hbox {C}$$ warming experienced from 1950 to 2016. Therefore, the future predictions of global warming should take into account the effects due to long-term changes in the galactic CRs, the low-level cloud condensation (LLC), etc. The concentrations of $$\hbox {CO}_{{2}}$$ increased in the upper atmosphere by 19% during the last 65 years. A strong correlation between LLC and GST suggests a linear relationship between these parameters. These observations are suggestive of the possible role of GCRs in global climate.