There is now strong evidence that the earth's climate is changing rapidly, due mainly to human activities. Increasing temperatures, sea-level rises, changes in precipitation patterns and extreme events are expected to increase a range of health risks, from the direct effects of heat-waves, floods and storms, to more suitable conditions for the transmission of important infectious diseases, to impacts on the natural systems and socioeconomic sectors that ultimately underpin human health. Much of the potential health impact of climate change can, however, be avoided through a combination of strengthening key health system functions and improved management of the risks presented by a changing climate. The critical first step in this process is to carry out a vulnerability and adaptation assessment. This allows countries to assess which populations are most vulnerable to different kinds of health effects, to identify weaknesses in the systems that should protect them, and to specify interventions to respond. Assessments can also improve evidence and understanding of the linkages between climate and health within the assessment area, serve as a baseline analysis against which changes in disease risk and protective measures can be monitored, provide the opportunity for building capacity, and strengthen the case for investment in health protection. WHO has responded to this global demand by building on past guidance and technical tools to outline a flexible process for vulnerability and adaptation assessment. In 2009, the WHO Regional Office for the Americas and WHO prepared draft guidance for this process, which was pilot-tested in studies across all WHO Regions. In July 2010, representatives of ministries of health from 15 countries came together in Costa Rica with WHO and subject area experts to share their experiences and provide feedback on how to improve the guidance for the conduct of vulnerability assessments. This document is the result of this process. It is intended not as a final, definitive guide but as an important part of an evolving set of resources that will support effective and evidence-based action to protect health from climate change.

The possible impacts of global climate change on different countries has led to the development and ratification of the Framework Convention on Climate Change (FCCC) and has a strong bearing on the future sustainable development of developing countries and countries with economies in transition. The preparation of analytical methodologies and tools for carrying out assessments of vulnerability and adaptation to climate change is therefore of prime importance to these countries. Such assessments are needed to both fulfill the reporting requirements of the countries under the FCCC as well as to prepare their own climate change adaptation and mitigation plans. The vulnerability and adaptation assessment guidelines prepared by the U.S. Country Studies Program bring together all the latest knowledge and experience from around the world on both vulnerability analysis as well as adaptation methodologies. It is currently being applied successfully by scientists in over fifty countries from all the regions of the globe. This guidance is being published to share it with the wider scientific community interested in global climate change issues. This guidance document has two primary purposes: • To assist countries in making decisions about the scope and methods for their vulnerability and adaptation assessments, • To provide countries with guidance and step-by-step instructions on each of the basic elements of vulnerability and adaptation assessments.

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.

As global climate change proliferates, so too do the health risks associated with the changing world around us. Called for in the President’s Climate Action Plan and put together by experts from eight different Federal agencies, The Impacts of Climate Change on Human Health: A Scientific Assessment is a comprehensive report on these evolving health risks, including: Temperature-related death and illness Air quality deterioration Impacts of extreme events on human health Vector-borne diseases Climate impacts on water-related Illness Food safety, nutrition, and distribution Mental health and well-being This report summarizes scientific data in a concise and accessible fashion for the general public, providing executive summaries, key takeaways, and full-color diagrams and charts. Learn what health risks face you and your family as a result of global climate change and start preparing now with The Impacts of Climate Change on Human Health.

Contributed articles on climate change.