CORRECTED-Global warming close to becoming irreversible-scientists | Reuters

" We are on the cusp of some big changes," said Steffen. "We can ... cap temperature rise at two degrees, or cross the threshold beyond which the system shifts to a much hotter state."...

Increased CO2 in the atmosphere has also turned oceans more acidic as they absorb it. In the past 200 years, ocean acidification has happened at a speed not seen for around 60 million years, said Carol Turley at Plymouth Marine Laboratory.

This threatens coral reef development and could lead to the extinction of some species within decades, as well as to an increase in the number of predators....

London School of Economics professor Anthony Giddens favours focusing on the fossil fuel industry, seeing as renewables only make up 1 percent of the global energy mix.

"We have enormous inertia within the world economy and should make much more effort to close down coal-fired power stations," he said.