The year 2016 felt like a great time for tackling climate change. Every country in the world had signed The Paris Agreement, with the Signatories promising to reduce greenhouse gas emissions.

As a result of the agreement each government formed a committee to report progress on climate change goals. For example, in the UK The Committee on Climate Change (CCC) undertook that role. The CCC’s 2020 report advises all government departments thus: ‘Ahead of the CCC's next adaptation progress report in 2021, demonstrate adaptation planning for a minimum 2°C and consideration of a 4°C global temperature rise (by 2100 from pre-industrial levels).’

What would a 4°C world look like? Author George Marshall described why his book, Don’t even think about it is important when he wrote three snapshots of a four-degree world. There will be an Earth of hell-like heatwaves of a magnitude the planet has not seen for five million years. Rain forests will be scorched,...