“What you see is, that the long-term production total looks like it would be about (…) two thirds of the reserves plus the production we’ve already had. If you just want to be crude about it, it’s comparable to the reserves but it looks like it’s less now. Now the IPCC range for this however gives a very large range up to 3.500 bn (?) tons that’s six, seven times what you get from either the curve fits or the reserves.” Energy Supplies and Climate - Dr. David Rutledge, Youtube, ab 31:28