The majority of previous climate change impact studies, summarised most recently in the IPCC Third Assessment Report, have based their assumptions about future climate on long-term changes in mean meteorological variables. Results suggest a gradual increase in stress being placed upon many of the world’s ecosystems and societies leading to, for example, falls in regional agricultural potential and biodiversity, increased energy demands and a reduction in the level of human comfort and population health. These studies, however, may be understating the problem. The use of long-term means masks the potentially greater threat of an increase in extreme events, which do not allow for adaptation to take place and are, therefore, far more likely to cause significant disruption to the natural and human environment.

This paper reports on new research into the nature and potential impact of future extreme temperature events in Europe. The aim of the study is to couple daily temperature data from several state-of-the-art climate models with two new impact models specifically designed to take advantage of such high-resolution data.

First, in order to assess model performance, an inter-comparison of present-day extreme near-surface air temperature series, constructed from the NCEP/NCAR reanalysis model and the Hadley Centre’s HadCM3 and HadRM3 climate models, was undertaken. Results were then compared with historical records from several sites across Europe, for the period 1948-2000. The behaviour of modelled extremes was compared with the observed records using various statistical techniques, including GEV analysis.

Second, two new impact models were developed to assess the potential impact of future temperature extremes on energy consumption and human health in Europe. These models link daily temperature statistics to national-level energy and health data for 18 European countries.

Preliminary results suggest that the latest global climate models are unable to adequately simulate the occurrence of even moderately extreme daily temperatures, especially in locations such as the European continental interior where there is a large seasonal cycle in air temperatures leading to hot summers and freezing winters.

Results from several early experiments conducted with the impact models, emphasise the regional disparities in potential impacts that are likely to be experienced across Europe. These distinctly different regional responses are the product of several interacting factors – the pattern of present-day weather events and the influence of regional climate change combined with differences in societal adaptation at the national level.