Soon, we're going to be living in a much hotter world. In Climatopolis, one of the world's leading urban and environmental economists tells us what our lives will be like. We have released the genie from the bottle: climate change is coming, and there's no stopping it. The fundamental question then becomes how our lives will play out in the hotter world. Some claim that our future is bleak. The 2008 Nobel Laureate Paul Krugman has argued that we are like a frog in a boiling pot, lamenting that while he knows that the climate pot is getting hot, we frogs are blissfully ignorant of the coming doom that climate change will cause. In contrast, Matt Kahn is optimistic about the quality of our lives in the city of the future, despite very different climate conditions than we face today. Urban life will go on in a hotter world. At the heart of his belief is our individual freedom of choice: not to mitigate but to adapt. Unlike birds and butterflies, we have a much wider variety of choices and options that allow us to protect ourselves from climate change. This personal freedom opens up pathways that will greatly help urbanites to cope with climate change. As climate change unfolds, billions of households will seek out strategies for protecting their families from harm. Some will move to higher ground to areas that are unlikely to flood while others will seek out products ranging from more energy efficient air conditioning to higher quality building materials to protect themselves from climate change's blows. This will play out differently around the world, and Kahn will take us on a tour of the world's major cities, from Los Angeles to New York to London to Mumbai, to see how different parts of the world along the economic development spectrum will fare in our hotter future.