There seems to be a lot of scientific evidence to support it although some serious studies do indicate otherwise. I do question the extent of human activity on global warming. I spent a couple weeks in Alaska last May. One of my stops was Glacier Bay. Something interesting happened there over the past 200 years. In 1794, Capt George Vancouver noted a small bay only a few miles deep and completely blocked by glaciers. In 1879, the naturalist John Muir visited the same area and found that the glaciers had retreated 40 miles. By the early 1900s, it had retreated over 20 more miles. This glacial retreat maps very well to the end of the "Little Ice Age."

What caused the end of the "Little Ice Age?" For that matter, what caused the "Little Ice Age" to begin? How about the global warming that ended the last big ice age about 10,000 years ago? If you can't answer those questions, then how can you pretend to understand how human activity might or might not be impacting the climate today? The answer is, you can't.

The climate does appear to be warming, just as it has done countless times in the past. Are you suggesting that humans are no longer able to adapt to change? If so, then perhaps we deserve to become extinct because we've become too fat, dumb, and lazy to deserve to survive. The fact of the matter is that, with every climate change, some suffer and benefit, depending on their ability to adapt to changing circumstances.

The most important greenhouse gas on Earth is water vapor. Perhaps we should do something about the oceans. There are factors like solar variability and Earth orbit perturbations that also affect climate. Believe it or not, there are forces at work here that are much beyond our abilities, egos, or political agendas.