With the world on “a highway to climate hell with our foot on the accelerator,'' the United Nations chief at the COP27 on Monday told dozens of leaders to ”cooperate or perish," on avoiding further climate catastrophe, singling out the two biggest polluting countries, China and the United States. Paul Leadley, a University Professor at Paris-Saclay and a member of the IPCC, the Intergovernmental Panel on Climate Change tells us more about Climate summit discussions.