Predicting long term freeze–thaw risks on Europe built heritage and archaeological sites in a changing climate

This work aims to predict the evolution in freezing processes due to climate change during the 21st century and the potential damage to historic structures and archaeological remains in Europe. We have developed a range of techniques to convert climate data into parameters related to the freeze–thaw processes and study their progression within the A2 scenario using the Hadley HadCM3 Model , from 1961 to 2099. Freezing and thawing is important because it represents a process where a phase change occurs at an exact temperature. A few degrees change in temperature or small percentages change in precipitation amount do not initially seem to present a threat to materials. However, freeze–thaw events occur at fixed temperature, so the effects of small temperature changes can be amplified. Our results suggest that much of temperate Europe will see a significantly reduced incidence of freezing in the future. This should mean that porous stone typically used in the monuments of temperate areas may be less vulnerable to frost damage in the future. Warmer temperatures in the far north look set to affect archaeological sites that have been preserved in the permafrost. These changes may also affect the foundations of structures and induce landslides. Exploring the range of possible changes allows us to contemplate appropriate contingencies and support strategic decision making by heritage managers.