Carbon markets are going global

, for years short of puff, have at last become one of the most widespread tools in the fight against climate change. By the end of 2021 more than 21% of the world’s emissions were covered by some form of carbon pricing, up from 15% in 2020. Ever more businesses have to pay regulators for the right to release a tonne of carbon dioxide into the atmosphere. Investors are getting interested too: trading on these markets grew by 164% last year, to €760bn ($897bn).That is undoubtedly great news. Carbon prices ensure companies that burn more fossil fuels are at a competitive disadvantage while green innovation is rewarded. The revenue from the sale of carbon permits, meanwhile, can be reinvested in renewable energy or other virtuous ventures as governments see fit.