Solar asymmetry and sun-earth connections

Abstract

The effect of solar activity on climate depends on the North-South solar activity asymmetry: the correlation between solar activity and a number of meteorological elements has opposite signs for predominantly more active Northern or Southern solar hemispheres. We find that the two hemispheres rotate differently, and show that the interplanetary magnetic field at the Earth's orbit is related to the differential rotation of the more active hemisphere. One feature that is persistently different in the two solar hemispheres is the prevailing magnetic helicity, which is carried to the Earth by magnetic clouds preserving the helicity of the source region of their origin. We show that the reaction of the atmosphere to the arrival of magnetic clouds depends on the helicity of the clouds.