Go to the following website and take a look at the transit of Mercury movie

http://www.nascom.nasa.gov

In this movie, you'll see the raging swirling inferno that is the solar disk. Slowly scooting across this utter chaos of the Sun is this tiny insignificant dot that is the planet Mercury. The planet Mercury is about a third the size of the Earth. The Sun is a relatively small star. We human beings (to paraphrase Douglas Adams) are an insignificant speck on an invisible dot. This arrogant misconception that we can actually alter fundamental physical processes is laughable. Yeah, we can blow away one of our cities with one of our largest nuclear weapons. However that same nuclear blast would be invisible if it occurred on the Solar photosphere. We are amazingly unimportant. Major climatic variations come and go with total indifference to human activity. Many planetary scientists believe that significant longterm variations in the Earth's climate is due to tiny subtle variations in the Solar intensity. It has been shown that climate shifts regularly occur simply due to the precession of the Earth's axis-of-rotation. Yeah, we can perturb the Earth's climate locally but that same perturbation can easily be overwhelmed by a random natural one. I'm for the preservation of wilderness and rational conservation policy (managing forests is within our limited capability). However believing that we can actually control the climate is nuts.

Gary