If all our fear and uncertainty over climate change could be distilled into a single statistic, then arguably it was delivered to an emergency summit on the future of the Antarctic last month.

Nerilie Abram at the Australian National University, Canberra, opened her presentation with a slide headlined “Antarctic sea ice has declined precipitously since 2014, and in July 2023 exceeded a minus 7 sigma event”.

At times, the noise of…