Trying to understand the complexity of the connection between the sun and the climate may actually require a working knowledge of atmospheric chemistry, a background in energy particle physics and the ability to draw on terrestrial history.
Experts agree that although the sun is a constant star, tiny variations (as little as 0.1% over an 11 year period) can result in significant climatic changes. The tiny variation can have as much impact as all of the Earth's other energy sources put together which in term affect the fragile atmospheric structures. These atmospheric changes will then filter down towards the surface of the Earth.
So what sort of effects can we expect from this? The first impact is probably related to the cooling of the atmosphere in the polar region correlates with damage to the ozone layer which will then impact and influence the wind movement that in turn normally regulate wind which in turn will change the normal path or storm activity and push them off their normal course. Essentially this means that some places on earth will experience a type of storm activity that they do not normally experience. This may sound very complicated, but it is reality. This type of change of weather activity has been well monitored and charted especially in the Pacific where the changes seem to be at the strongest.
Over the past few years there has been a lot of finger pointing at the reasons behind global warming. Given the evidence of the 0.1%variation over an 11 year period, it has been suggested that the warming is not global as originally thought, it’s regional instead. This claim is also substantiated by using the measurements from the study that focussed on the Pacific. Working on that premise it can be argued that not all areas and locations are equally affected. To make this claim scientists used measurements and data from a variety of areas and natural resources such as ice cores and tree rings. But there is a debate as to whether that is sufficient evidence to support the theory of solar variations.
If we look back further into the Earth's history, we discover that scientists experienced difficulty variations in making a connection between tree rings and ice cores, rather than solar activity they felt that variations in the Earth's magnetic field and atmospheric circulation had more far reaching effects. Generally it is now though that by studying the geology of Mars may give a more accurate story.