Cambridge Uni finds summer 2023 was hottest in last 2000 years
It was almost four degrees warmer than the coldest summer during the same period
Researchers at Cambridge University have found that 2023 was the hottest summer in the Northern Hemisphere in the past two thousand years
It was almost four degrees warmer than the coldest summer during the same period.
Although 2023 has been reported as the hottest year on record, the instrumental evidence only reaches back as far as 1850 at best, and most records are limited to certain regions.
Now, by using past climate information from annually resolved tree rings over two millennia, scientists from the University of Cambridge and the Johannes Gutenberg University Mainz have shown how exceptional the summer of 2023 was.
Even allowing for natural climate variations over hundreds of years, 2023 was still the hottest summer since the height of the Roman Empire, exceeding the extremes of natural climate variability by half a degree Celsius.
“When you look at the long sweep of history, you can see just how dramatic recent global warming is,” said co-author Professor Ulf Büntgen, from Cambridge’s Department of Geography. “2023 was an exceptionally hot year, and this trend will continue unless we dramatically reduce greenhouse gas emissions.”
The results, reported in the journal Nature, also demonstrate that in the Northern Hemisphere, the 2015 Paris Agreement to limit warming to 1.5C above pre-industrial levels has already been breached.
The research was supported in part by the European Research Council.