So to completely deny that humans have anything to do with the earths climate getting warmer is pretty hard to do with a straight face IMO. We might not be the only cause, but we are one of the causes.
Sure, but are we a significant cause? Minor climatic shifts have been happening regularly throughout our recorded history, the Little Ice age ended in the 1850s, a 1 degree shift in global temperature that corrected (or changed) in something like 5 years (according to ice cores pulled from the Rockies). The Little Ice Age ended the Medieval Optimum, a time when they were growing grapes in Greenland. What caused the Little Ice Age? What caused the Medieval Optimum? Does either period represent whatever the average climate is supposed to be?
Quite frankly I'm pretty skeptical that humans will get it together and solve the greenhouse gas issue, it is a "Tragedy of the Commons" on a global scale.
Lamont