Other scientists, such as physicist Myles Allen of the University of Oxford, examine the problem from the opposite side: How much more CO2 can the atmosphere safely hold? To keep warming to below 2 degrees C, humanity can afford to put one trillion metric tons of CO2 in the atmosphere by 2050, according to Allen and his team—and humans have already emitted half of that total. Put another way, only one quarter of the world's remaining known coal, oil and natural gas reserves can be burned. “To solve the problem, we need to eliminate net emissions of carbon dioxide entirely,” Allen says. “Emissions need to fall by 2 to 2.5 percent per year from now on.”
So peak oil won’t solve climate change for us by declining at 4 to 5% per year if coal and gas consumption continues to increase. However, I’m hoping some of the ‘peak coal’ people are right and that the economics of coal production radically changes after 2025 as some have predicted. That seems to be the only thing that might save us from catastrophic climate change.