In the wake of dire reports on rising greenhouse gas levels, dozens of world leaders — not including America's president — will be among 29,000 people gathering in Madrid for COP25, a two-week climate change conference. "The point of no return is no longer over the horizon," warned U.N. Secretary-General António Guterres. Meanwhile, nonprofit Save the Children reported that 33 million people in Africa alone are facing food insecurity because of droughts and cyclones.
What needs to happen? "We simply have to stop digging and drilling," Guterres urged, and instead embrace the "vast possibilities" offered by renewable energy.
OZY takes you to the frontiers of countering global warming.