When the sun is quiet, we on earth can freeze. The effects of the sun on the earth’s climate is huge. The sun typically has an 11 year cycle of sunspot activity and history tells us that when it is low in sunspot activity then the world cools. At the moment Solar Cycle 24 is extending and is very low in sunspots.
According to the Laymans Sunspot Count, the sun in the current Solar Cycle 24 could peak as low as 30 – 35 which is now tracking below Solar Cycle 5 which was part of a cold period on earth that correlated with the Dalton Minimum. And current discussion including a theory by Livingston & Penn is that we are heading towards no sunspots by 2015 which would be far worse than Dalton and more like the Maunder Minimum in the late 1600’s which was even colder of a time on Earth (the biggest of the little ice ages).
Solar flux and solar wind are low as well. Henry Svensmark has a theory that low sunspot numbers correlate with more cosmic rays hitting the earth which allow for more hydrogen in our atmosphere, which interact with oxygen, to make more water vapor and more cloudiness. This means lower temperatures and more rain/snow. All this is happening while we are in a cold pacific decadel oscillation (PDO) and a strong La Nina (both cooling weather signals). The recent flooding and snowstorms worldwide could be the result.