What if net-zero isn’t enough? Inside the push to ‘restore’ the climate.

Cutting down on greenhouse gases to the point where they aren't accumulating in the atmosphere isn't enough to corral climate change; science needs to focus on actively removing carbon dioxide as well. That's according to a group of scientists who want more work on climate restoration, not just net-zero greenhouse gases. Kim Cobb weighs in on whether it may already be too late for some aspects of the environment.