 So air conditioners that we use in our buildings, all these things put out waste heat. So if a lot of people are living close together, too, you're going to get a lot of additional heat. And all these things come together in cities. And that's why you have severe urban heat islands. You can have elevated heat wherever there's a lot of pavement and a lot of buildings. But in cities, it tends to be a lot worse. Talk to me about some of the heat islands and some of the worst cities for this. I believe you named 10 of them, some of which might surprise some people.