HEATCOST will compute the global current and future level of cardiopulmonary diseases due to extreme heat and air pollution, including smoke from wildfires. Possibilities to reduce the health damage will be considered and a possibility for adaptation will be evaluated together with the associated costs. Heat increases mortality and morbidity for cardiovascular and respiratory diseases, which together constitute cardiopulmonary diseases (CPD). The risk of wildland fires increases during periods of extreme heat and decreasing precipitation, and can cause intense air pollution. Simultaneous occurrence of extreme heat and air pollution can worsen the health effects. Different regions in the world may show different effects, depending various local factors. Populations at highest risk include older adults, children, socially isolated individuals, and individuals with chronic diseases.