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

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.

This bibliography is mainly concerned with the influence of weather on crops in connection with the germination, growth, development, susceptibility to disease, and final yield. It contains references to laboratory studies, field studies, and statistical studies on the effect of different conditions of temperature, precipitation, humidity, light, and wind on vegetation in many parts of the world.

capable of providing at least a relative measure of stomatal aperture were first used shortly thereafter (Darwin and Pertz, 1911). The Carnegie Institution of Washington's Desert Research Laboratory in Tucson from 1905 to 1927 was the first effort by plant physiologists and ecologists to conduct team research on the water relations of desert plants. Measurements by Stocker in the North African deserts and Indonesia (Stocker, 1928, 1935) and by Lundegardh (1922) in forest understories were pioneering attempts to understand the environmental controls on photosynthesis in the field. While these early physiological ecologists were keen observers and often posed hypotheses still relevant today they were strongly limited by the methods and technologies available to them. Their measurements provided only rough approximations of the actual plant responses. The available laboratory equip ment was either unsuited or much more difficult to operate under field than laboratory conditions. Laboratory physiologists distrusted the results and ecologists were largely not persuaded of its relevance. Consequently, it was not until the 1950s and 1960s that physiological ecology began its current resurgence. While the reasons for this are complicated, the development and application of more sophisticated instruments such as the infrared gas analyzer played a major role. In addition, the development of micrometeorology led to new methods of characterizing the plant environments.