Economist: MARKETS can misprice risk, as investors in subprime mortgages discovered in 2008. Several recent reports suggest that markets are now overlooking the risk of "unburnable carbon". The share prices of oil, gas and coal companies depend in part on their reserves. The more fossil fuels a firm has underground, the more valuable its shares. But what if some of those reserves can never be dug up and burned?
If governments were determined to implement their climate policies, a lot of that carbon would...