Economy unlikely to stop pumping.

• Position: Climate Change

"The Paris [Climate] Agreement laid out a dramatic new vision, but there is still much work to be done to turn that broad outline into the concrete climate policy changes around the globe that are needed to reduce fossil fuel consumption and the odds of disruptive climate change," says Michael Greenstone, director of the Energy Policy Institute at the University of Chicago (Ill.). "However, one thing is clear: counting on the fickle finger of fate to point the way to cheaper low-carbon energy sources, without market and policy forces pushing us there, mistakes hope for a strategy."

Writing in the Journal of Economic Perspectives, Greenstone and coauthors Thomas Covert, assistant professor in the School of Business at the University of Chicago, and Christopher Knittel, professor of energy economics and director of the Center for Energy & Environmental Policy Research at the Massachusetts Institute of Technology, Cambridge, maintain that the continued use of fossil fuels will increase global temperatures by 10[degrees]-15[degrees]F--and those numbers do not account for advances in fossil fuel extraction techniques that could make resources we cannot even extract today economically accessible, such as oil shale and methane hydrates, potentially adding another 1.5[degrees] to 6.2[degrees] of warming.

The economists explored whether market forces alone would cause a reduction in fossil fuel supply or demand. By studying the history of fossil fuel exploration and technological progress for both clean and dirty technologies, they conclude that it is unlikely that the world will stop relying on fossil fuels soon.

As one piece of evidence, the economists studied the amount of reserves in the ground over the last three decades compared to world consumption. For the last 30 years, reserves of oil and natural gas have grown at least as fast as consumption. As a result, the world always has had 50 years of future consumption stored as reserves in the ground. This was equally true in boom years (when prices were high) and bust years.

Technological progress--such as the development of hydraulic fracturing and the ability to extract oil from tar sands--is at least partially responsible for a long-term...