Summer 2023 was the hottest in 2,000 years: study

PARIS: Last year´s northern hemisphere summer was the hottest in 2,000 years, according to a new study published on Tuesday.

Scientists say 2023 was the hottest year globally since records began in 1850, but the study in the journal Nature indicates human-caused climate change pushed northern summer highs well beyond anything seen in two millennia.

“We shouldn´t be surprised,” the study´s lead author Jan Esper told AFP.

“For me it´s just the continuation of what we started by releasing greenhouse gases” that cause global warming, said Esper, a professor of climatology at Germany´s Johannes Gutenberg University.

Scientists used tree-ring data from sites across the northern hemisphere to estimate global temperatures between the first century AD and 1850, before the advent of modern observational instruments.

The conservative estimate found that 2023 was at least 0.5 degrees Celsius hotter than the warmest northern hemisphere summer of that period in AD246. Otherwise, it was 1.19 degrees warmer.

Study co-author Max Torbenson told reporters that 25 of the last 28 years exceeded the summer highs of AD246 -- the hottest year before modern temperature records began.