Climate scientists did not scaremonger. If anything, they undersold the scale of the crisis

The UN warns there has been a ‘disturbing acceleration’ in the number, speed and scale of temperature records tumbling this year. As Cop28 prepares to open its doors in Dubai, Roger Harrabin says we should begin imagining a world where temperatures have risen by 3C... because that is where we are heading

A boat travels through a section of the Amazon hit by drought in the state of Amazonas, near Manacapuru, Brazil (AP)

As world leaders prepare for the annual UN climate talks – starting in Dubai on Thursday – I’m inviting you on a voyage of meteorological imagination, with a little help from the pop star Taylor Swift, the Panama Canal and the Antarctic.

Swift recently cancelled a concert in Rio after a young woman died at one of her gigs as the city suffered from extreme heat. Rio has wilted as the heat index measuring the combination of temperature and humidity reached a debilitating 58.5C. Further north, the Amazon has shrunk to a record level. The extremes have happened with a global temperature rise of an apparently innocuous 1.2C above pre-industrial levels.

Meanwhile, drought has starved the Panama Canal, forcing a major cut in shipping. It has squeezed other great waterways like the Rhine, Mississippi and the Suez Canal. Again, with a temperature rise of just 1.2C. In Antarctica, researchers said they were “scared” by temperatures reaching 4.8C warmer than the long-term average, propelled upward by that global rise of 1.2C.