Al Gore does a 30-minute Reddit Ask Me Anything: "There are at least 15 deeply researched separate lines of evidence that all confirm man-made global warming...There is as strong a consensus as you will find in science, with the possible exception of the existence of gravity"

I am Al Gore, founder and chairman of the Climate Reality Project – AMA : IAmA

There are at least 15 deeply researched separate lines of evidence that all confirm man-made global warming. They are all consistent, each with the others. Every National Academy of Science on the planet agrees with the consensus. The Academies describe the evidence as "indisputable". Every professional scientific society in every field related to climate science and earth science also agree. And 97-98% of climate scientists worldwide most actively publishing also agree. Animals and plants also agree -- in that they are moving their ranges by latitude and altitude to find climate niches similar to the ones in which they evolved. Even if you leave climate science completely out of it and just measure extreme temperatures, the statistical record of global temperatures shows that three-standard deviation events have increased from 0.25% of the time (from 1951-1980) to 10% of the time now. There is as strong a consensus as you will find in science, with the possible exception of the existence of gravity.

Lots of questioners are asking about ManBearPig.