Climate change poses many challenges that affect society and the natural world. With these challenges, however, come opportunities to respond. By taking steps to adapt to and mitigate climate change, the risks to society and the impacts of continued climate change can be lessened. The National Climate Assessment, coordinated by the U.S. Global Change Research Program, is a mandated report intended to inform response decisions. Required to be developed every four years, these reports provide the most comprehensive and up-to-date evaluation of climate change impacts available for the United States, making them a unique and important climate change document. The draft Fourth National Climate Assessment (NCA4) report reviewed here addresses a wide range of topics of high importance to the United States and society more broadly, extending from human health and community well-being, to the built environment, to businesses and economies, to ecosystems and natural resources. This report evaluates the draft NCA4 to determine if it meets the requirements of the federal mandate, whether it provides accurate information grounded in the scientific literature, and whether it effectively communicates climate science, impacts, and responses for general audiences including the public, decision makers, and other stakeholders.

Summarizes the science of climate change and impacts on the United States, for the public and policymakers.

Today's greater public awareness of how climate affects our quality of life and environment has created an increasing demand for climatological information. Now this information is available in one convenient, accessible source, The Encyclopedia of Climatology. This comprehensive volume covers all the main subfields of climatology, supplies data on climates in major continental areas and explains what is known about the causes of climatic processes and changes. Contents include articles on bioclimatology, El Niño, climatic models, world regional climates, civilization and climate, climatic variations and the greenhouse effect.