In the dying days of 2014, I wrote a story for the Financial Times that people said was idiotic. It suggested that oil companies such as Shell and ExxonMobil would “cease to exist in their current forms within 35 years” under measures being discussed at UN talks on the global climate accord due to be struck in Paris the following year.

Fossil fuels would have to be phased out by 2050 under one option, or only used if countries could bring about something called net zero emissions. In other words, emissions would have to nosedive so much that any still being pumped out after 2050 could be offset by, say, planting forests that suck up carbon dioxide as they grow.