Predicted climate change scenarios published by the UK Climate Impacts Programme suggest that, on average, summers are likely to be hotter and drier than over the past century. Changes in average rainfall, the frequency of flood events and storms are also predicted. These predictions have numerous implications for British forest ecosystems, as well as the potential to directly alter the preservation of archaeological materials and the wider historic landscape.
Some archaeological remains may benefit from preservation in increasingly drier environments, while other sites can to some extent be managed to minimise any impacts from hotter, drier summers. However, this has implications for wetland sites that well known for their good preservation of archaeological materials, where desiccation of organic material may lead to its loss.
In addition to the impacts of climatically driven changes, there are many indirect factors such as changes in a site’s floral composition, associated litter decomposition and soil fauna that can also alter the burial environment, with further implications for archaeological preservation.
Where climate change is considered a significant threat to archaeological evidence, rescue excavation is a possible option. However, it is not possible to move and relocate the historic landscape. As such, where ancient woodlands are to be retained, eventual changes in their species composition may eventually be necessary. If veteran trees are lost or ancient woodland changes its characteristics, many other associated flora and fauna could equally struggle to adapt.
The challenge faced by historic environment managers
Climate change is not a new phenomenon. Many archaeological remains and veteran trees have, throughout their existence, been subject to periods of change. Many heritage features will remain unaffected by the changes predicted, whilst others may arguably benefit.
- The rates of change over the coming century may be greater than experienced since the last ice-age, and biocultural features may not be able to adapt as they have in the past
- Short-term impacts may mean that more individual trees show signs of susceptibility to drought conditions or related stresses.
The challenge now faced is to identify areas most at risk from climate change (particularly living features) and develop mitigation or adaptation strategies where possible and practical.
Modern society values its historic landscape and typically strives to preserve it in its current form or even recreate aspects of the past. However, where such aims are targeted at trees and woodland, change with time may be inevitable and preserving the past impossible.