… many scientists have pointed to a two-degree rise in global temperatures as the most we could possibly deal with.

If we spew 565 gigatons more carbon into the atmosphere, we’ll quite possibly go right past that reddest of red lines. But the oil companies, private and state-owned, have current reserves on the books equivalent to 2,795 gigatons — five times more than we can ever safely burn. It has to stay in the ground.

Put another way, in ecological terms it would be extremely prudent to write off $20 trillion worth of those reserves. In economic terms, of course, it would be a disaster, first and foremost for shareholders and executives of companies like ExxonMobil (and people in places like Venezuela).