France, Sept. 10 -- In response to the assessment by the Copernicus Climate Change Service, the UN warned that until humanity weaned off fossil fuels, the planet would only push deeper into uncharted territory.

Copernicus observations go back to 1940 but other evidence - such as ice cores, tree rings and coral skeletons - allow scientists to place today's climate against a much longer historical context.

"Humans haven't seen temperatures as hot as today for, arguably, at least the last 100,000 years," Samantha Burgess from the European Centre for Medium-Range Weather Forecasts, which oversees Copernicus, told AFP.

Global average air temperatures in August were 16.96C, Copernicus said - surpassing by 0.01C the previous all-time monthly ...