Epic heatwaves. Raging wildfires. It has been a crazy summer of intense weather. On this episode, I talk to Dr. Michael Mann — he’s one of the world’s leading climate scientists and he says this summer’s weather is overwhelming proof that climate change is threatening the planet in a profound way. He argues that the cost of not seriously combatting climate change now vastly outweighs the cost of doing everything we can to reduce carbon emissions. He also addresses the possibility of a “Hothouse Earth” scenario, in which we see runaway climate change that is worse than anyone had previously predicted. And he discusses some of his problems with a recent New York Times report on whether or not we could have stopped climate change 30 years ago.