How much can we reduce carbon emissions that come from making and using stuff? Quite a bit, according to the University of Cambridge team behind this book. They look closely at the materials that humans use most, with particular emphasis on steel and aluminum, and show how we could cut emissions by up to 50 percent without asking people to make big sacrifices. Although the topic can be dry as a desert, the authors keep it light with lots of colorful illustrations and clever analogies without sacrificing clarity or rigor. I learned a lot from this thoughtful look at a critical topic. (You can download it free on the authors’ site.)