“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”.