One new mine is the same as millions of nuclear bombs of heat.

By the mining company’s calculation, the expanded project will add 535 million tonnes of carbon dioxide equivalent to our atmosphere over the lifetime of the mine.

1.3% of a year’s global warming gives roughly 0.1 zettajoules worth of extra heat through burning the output of an expanded Mount Pleasant coal mine.

We can think of it instead as around 1.7 million Hiroshima bombs worth of extra heat.

If the 25 proposed new coal mines and three recently approved projects go ahead, they would add 12,600 million tonnes of CO₂ emissions to the atmosphere.