Solar Irradiance vs. Climate...

Some scientists advocate the notion that small changes in solar irradiance (basically the brightness of the sun) make a major contribution to the changes in the Earth's climate, most especially the average temperature. I've seen bits and pieces of their work before, and while there are some very suggestive correllations, I haven't seen much in the way of plausible mechanisms explored.

Still, the apparent fact that solar irradiance is well-correllated with average global temperatures is very suggestive. I think we can be fairly certain that climate changes on Earth do not cause the sun to get brighter or dimmer. It's at least plausible on the face of it that changes in solar brightness do cause temperature changes on Earth. And it seems highly unlikely that a correllation like this could be a coincidence:
There's much more where this came from, in a very readable seven-page report available here (PDF). The discussion on the current solar cycle is particularly interesting...