Methodology to assess thermal extremes mortality risk in urban areas

the impact of heat waves on mortality has been the subject of numerous studies and the focus of attention of various national and international governmental bodies. in the summer of 2003 alone, which was exceptionally hot, the number of deaths in 12 european countries increased by 70,000. the overall trend of warming will lead to an increase in frequency, duration and intensity of heat waves and to an increase in heat related mortality. the need to assess the risk of death due to extreme heat, at a detailed spatial scale, has determined the implementation of a research project based on a general model of risk for potentially destructive natural phenomena; the model uses the relationship between hazard and vulnerability and was designed primarily for urban areas. the major hazardous meteorological variables are those that determine the thermal complex (air temperature, radiative temperature, wind and humidity) and the variables related to air quality (mainly ozone and particulate matter). vulnerability takes into account the population sensitivity (at various spatial scales) and their exposure to thermal extremes.