So you mean that climate change is not currently happening due to natural causes?Thanks for posting this. The argument that present climate change is caused by natural causes proposed is such a prominent talking point by deniers. I am very impressed with Dr. Richard Alley (primarily finding out about him through your website). Thanks for providing a tool for me with this bite to counter one of the skeptics and deniers most common misconceptions that climate change is naturally occurring. Even more, when one studies the science of climate change, it becomes even more clear that the present climate change is primarily caused by man. These were the main factors that took place in the past that triggered glacial and inter glacial ages: the sun, the tilt of the earth, the rotation of the earth around sun, and the wobble of the earth. None of these factors are having a significant impact right now. It is by far the increase in carbon dioxide by man burning fossil fuels that is increasing the average global temperatures. As a result, this is triggering climate change.