And they warn the repercussions will be felt for “tens of generations”. The build-up of the key greenhouse gas – one of the leading causes of global warming – could be larger than last year as changing weather patterns in the Pacific look set to reduce the ability of natural “sinks”, such as forests or grasslands, to absorb excess carbon in 2019. Changes in the weather affect plants growing and absorbing carbon dioxide.
This reduction, combined with rising emissions from human activity, mean experts expect to see one of the largest rises in the concentration of atmospheric carbon dioxide in 62 years of measurements.
Professor Richard Betts, of the Met Office Hadley Centre, said: “Since 1958, monitoring at the Mauna Loa observatory in Hawaii has registered around a 30 percent increase in the concentration of carbon dioxide in the atmosphere.
“This is caused by emissions from cement production, deforestation, and fossil fuels and the increase would have been even larger if it were not for natural carbon sinks which soak up some of the excess.
“This year we expect these carbon sinks to be relatively weak, so the impact of record high human-caused emissions will be larger than last year.”
Dr Dann Mitchell, at University of Bristol, said a large proportion of carbon dioxide released into the atmosphere remains “for thousands of years”, and the repercussions of the Met Office forecast “will also be felt for tens of generations”.