Just this week, a group of 27 prominent scientists, representing all major continents, issued a joint statement that explains that burning all known fossil-fuel reserves would produce about 3,800 gigatonnes of CO2, or 1,053 GtC, with coal alone accounting for more than half. Simply put, if the world burns its known coal reserves using current technologies, it is likely to push global temperature rise far beyond 2ºC.