The previous posting closed with: Low Sunspot numbers and low F 10.7 indicate low solar activity. How this activity translates to cooler weather is not clear. The correlation between low activity and cooler weather has been know for several hundred year (or perhaps longer— recently read that the Chinese recorded Sunspot numbers many century’s ago and reported this correlation.)
One possible explanation is the Svensmark theory. This theory begins with high energy galactic cosmic rays (GCR) entering the Earth’s atmosphere where they collide with atmospheric molecules of oxygen. The collisions shatter the molecules and the resulting particles become nuclei for cloud droplets from which clouds are formed. Clouds reflect a significant amount of the Sun’s radiation back into space. The weaker the Sun’s magnetic field (low solar activity), the more GCR enter the atmosphere. The more clouds, the more cooling. This is opposed to the situation where the Sun’s activity is high, fewer GCR result in fewer clouds.
Climate Change Sanity 