Heatwaves and health: Guidance on warning-system development

Heat or hot weather that lasts for several days, often referred to as “a heatwave” can have a significant impact on society, including a rise in mortality and morbidity. Heatwaves also place an increased strain on infrastructure (power, water and transport). Clothes and food retailing, tourism and ecosystem services can also be affected, such that there may be socioeconomic “winners and losers” from heatwave events. In some instances, heatwaves may even trigger social disturbances at a number of levels. The impacts of heatwaves can be great and sometimes catastrophic, as manifested by the large number of heat-related deaths recorded across Europe in July and August 2003, and the Russian Federation in July and August 2010. While the effects of heat may be exacerbated in cities, due to the urban heat island (UHI) effect, the livelihoods and social wellbeing of non-urban communities can also be severely disrupted during and after periods of unusually hot weather.