Climate Change, Migration, & Humanity's Niche, with Tim Kohler & Marten Scheffer

A new report finds that over the next 50 years, 1 to 3 billion people could be living outside the climate niche that has "served humanity well over the past 6,000 years." Tim Kohler and Marten Scheffer, co-authors of "Future of the climate niche," discuss what was surprised them in this research, what it means historically when huge populations move, and why there's reason to be hopeful about humanity's future.