The Working Group 1 Report and National Climate Assessment tell us in no uncertain terms that climate change is happening, and that it is primarily due to human activities. Land and sea temperatures are rising. Glaciers and ice sheets are melting. Oceans are acidifying. Working Group II tells us about the impacts to the environment and the economy as warming increases, including crop failures, more frequent extreme weather events, and conflict over water and other scarce resources. We already see all of this in every region of the United States and around the world. Working Group III lays out our options for reducing our greenhouse gas pollution and shifting our economy to run on low-carbon energy, increasing efficiency and investing in reforestation.