For “Marketplace” host Kai Ryssdal, joining the Navy fresh out of college was a defining chapter in his life. It was the 1980s; the Cold War and the Soviet Union was the greatest threat. Fast-forward through 40 years — and one career change — and the threat looks different. Climate change has no face or flag, but it will fundamentally change the way the U.S. military trains and fights. It already has. “How We Survive” is an award-winning podcast from Marketplace about the messy business of climate solutions. In our sixth season, Kai Ryssdal travels to far corners of the world to shine a ligh...