We are now putting carbon into the atmosphere at a rate unprecedented since at least the age of the dinosaurs, scientists say.

The researchers have examined ocean sediments laid down during the so-called Palaeocene-Eocene Thermal Maximum - a dramatic warming event some 56 million years ago.

They find the amount of CO2 going into the air at its onset was four billion tonnes a year at most.

Today's figure is 10 times as big.

[whole BBC article]