Earlier this month, presidents Barack Obama of the US and Xi Jinping of China made an important symbolic gesture when they committed their countries, the two largest greenhouse gas emitters, to the Paris climate agreement. It was the clearest signal yet to investors worldwide that they need to think about the implications of global warming for their portfolios.
On Friday afternoon there was an example of what that might mean when Mr Obama’s administration issued an order temporarily blocking construction on a section of the Dakota Access oil pipeline. The move was a response to local concerns raised by the Standing Rock Sioux Tribe about potential damage to historic sites and the threat of oil spills. But it is the global issue of climate change that has raised the profile of Dakota Access, making it into a cause célèbre for US environmental campaigners. Bill McKibben of 350.org, which played a key role in the successful effort to stop the Keystone XL pipeline from Canada, has suggested that Mr Obama could block Dakota Access permanently, on the grounds that it would exacerbate the threat of climate change.
Last month, the White House’s Council on Environmental Quality issued new guidance for federal agencies, making clear that their decisions should take into account “the potential effects of a proposed action on climate change”, and quantify their consequences for greenhouse gas emissions. Dakota Access is intended to carry crude oil 1,172 miles from North Dakota, a centre of the US shale