The 2014 WHO conference on health and climate.

Editorials 546 As discussed elsewhere in this issue of the Bulletin of the World Health Organization , human health and climate change are inextricably linked. This month, the World Health Organization (WHO) will, for the first time, bring together high-level government representatives , development partners and technical experts in a global conference on climate and health. What does the conference plan to achieve, how can it empower countries to protect health from climate risks and gain the health benefits of addressing climate change, and why is it needed now? The first aim is to provide the evidence for health actors to engage on this issue. The Intergovernmental Panel on Climate Change's March 2014 report 4 updated the evidence on the health risks of climate change. It concluded that climate change acts mainly by exacerbating existing health problems but also affects water, food and nutrition security, and that the most vulnerable populations are those that are already most affected by climate-related diseases. It highlighted the possibility of high-end climate scenarios – including warming by 4–7 °C over much of the globe by 2100 – that would lead to some critical thresholds being crossed. Such warming might make outdoor physical activity in the hottest parts of the year dangerous in many locations. Some human habitats may be lost altogether as low-lying countries are submerged by rising seas. Climate change is a threat to a bottom line of sustainable development – human health. New studies and practical experience can help guide an appropriate response. There is evidence that poverty alleviation and preventive health programmes can decrease vulnerability and override some of the risks presented by climate change. Evidence also shows that actions to reduce greenhouse gas emissions and air pollution can result in large health gains. Air pollution is estimated to cause one in every eight deaths, 5 so reduction of emissions of black carbon and other short-lived pollutants may not only slow warming but also avert almost 2.5 million deaths annually. 6 The deaths and disease thus prevented could offset much of the cost of greenhouse-gas mitigation. 7 In developing more socially beneficial, cost–effective and widely supported policies for the mitigation of climate change, the arguments, evidence and voices of the health community are critical. This WHO conference will explore ways of building health resilience to climate risks, for example through improving health, water and sanitation services. Participants will also deliberate how …