Urban heat

Abstract

[Is heat becoming a major threat to cities? Following the heat wave in Europe in 2003, which is estimated to have caused the deaths of 70,000 people, municipal authorities began to develop adaptation and mitigation plans and programs. Legal obligations to consider climate change within various development projects have been defined, e.g. by the latest amendment of the EU EIA (Environmental Impact Assessment) Directive (2014/52/EU) and the Federal Building Code (BauGB §1a (5)). However, urban heat hazards have not yet received as much attention as, for example, carbon dioxide emissions as drivers of global warming. Dense urban structures, high buildings, dark surfaces, and high population densities trigger urban heat effects. With about 3/4 of Europeans living in cities, measures to reduce heat-related impacts are needed. This paper evaluates how German cities have implemented measures towards climate change adaptation. The results show that 24 out of 30 cities have developed mitigation and/or adaptation plans, with a majority focusing on mitigating CO2, indicating less awareness of urban heat hazards. Moreover, we found elaborate and comprehensive examples which might serve as blue-prints for adaptation strategies. Based on the inhomogeneous scope of the different plans and programs, there remains a need for guidance and more knowledge exchange among the cities on mitigation/adaptation options and preferably information on their effectiveness, to further assist cities in tackling heat stress.]