Professor Steffen says the Anthropocene age will continue for some considerable time.

"Even if we cut down emissions to zero or close to zero tomorrow, there would be significant amounts of extra CO2 up there for centuries into the future, and I think also in terms of biodiversity loss, there is what some people call committed biodiversity loss, or species that are on their way to extinction and there probably isn't much we can do to turn them around," he said.