What Are the Effects of Climate Change on the Historic Environment?
The consequences and scale of climate change are daunting. After considering adaptation, mitigation, direct and indirect impacts and resilience measures, it can be difficult to know what actual physical environmental risks threaten the historic environment. Below are some brief considerations of landscapes, buildings, archaeology, floodplains, coasts and marine environments.
Climate change could significantly impact a range of species and habitats by the year 2050 according to an international report.
Environmental changes will create both opportunities and also foster probable loss. Some flora and fauna may be able to expand their habitat range, see our publication on problem weeds.
Species that are currently at the threshold of their tolerance for environmental conditions may be lost.
Increased warmth may also encourage a rise in the number of invasive plant and animal species.
This could change the character of historic and designed landscapes by reducing numbers of or killing off native flora and fauna.
Hotter, drier conditions may also increase the risk of fire, particularly for upland landscapes.
Flood water inundation and saturation can also damage historic buildings and designed landscapes, particularly if standing water conditions persist.
Extreme weather, changes in temperature and future water availability will likely alter the character of parks and gardens, whose particular species are part of their appeal. See a UK Climate Impacts Programme Report about the effect on gardens.
Historic landscapes of all types may also come under further pressure from longer growing seasons. Whilst this could be seen as an opportunity for the introduction of new crops and practices, it may alter the inherent character of the English landscape significantly.
Multiple factors will also affect historic buildings , increasing and varying the types of maintenance needed. See our advice pages for more information on maintaining your home.
Whilst unpredictable and severe weather in the form of floods and storms is likely to be an ongoing issue, continued change will more regularly stem from individually less severe, but nevertheless cumulatively significant impacts.
Global warming is likely to encourage both fungal and plant growth and insect infestation, affecting historic building materials. Structural problems may also increase from changing extremes and fluctuations (heat as well as cold) in temperature.
In dry conditions soil shrinkage, particularly of those that are clay-rich, can lead to building subsidence, structural deformation and collapse in the most severe cases.
Flooding is also a major problem, both inland (see our report on flooding risk to the inland English Heritage estate) and on the coast (see below).
The planet’s changing climate means that some archaeology which was relatively safely preserved under the ground is now at risk of damage due to extremes in temperature and cycles of wetting and drying. Because both buried archaeology and the conditions under which it survives are varied, there is not one single solution to environmental change.
Soil saturation and shrinkage, changes to soil chemistry, and indirect effects like stratigraphic alteration are all possible outcomes of climate change. Wetland sites and the organic materials they preserve in anaerobic (oxygen free) conditions are particularly vulnerable, see our previous research on wetland heritage. Desiccation of soils and lowered groundwater levels will increase the risk of decay to waterlogged archaeological and palaeoenvironmental remains.
Preservation in situ (in the ground) will become increasingly difficult as these damaging cycles create stressful environments for buried archaeology, see our guidance on the preservation of archaeology in situ.
Floodplain, coastal and marine environments
All types of asset may be affected by the erosive power of high energy flood water (e.g. buried archaeology in floodplains) and physical damage from entrained objects (e.g. bridges). Also, sand dunes, peats and other inter-tidal deposits are likely to come under greater threat if wave energy and storminess increase.
Floodplains and valley bottoms are also likely to experience an increase in the frequency and intensity of floods, destabilising structures and bridges as river courses change. Low-lying areas are also at potential threat from predicted sea level rise and also storm surges, which will likely become more intense over time.
Coastal sites are vulnerable to sea level changes, erosion and the effects of storm waves. See our previous research into coastal sites.
Coastal and marine erosion is also already taking place at an accelerated pace. Many of England’s coastal and lowland assets will be at risk, as will the character of the landscape itself as flood defences are strengthened and assets potentially relocated. Assets on the coastal fringe will become increasingly at risk from inundation, damage or loss from erosion, with foreshore and cliff-top equally vulnerable, depending on geology. For a case study, see our assessment of the risk the of coastal erosion to the English Heritage estate.
Because inevitable loss is especially likely in coastal areas, Historic England carries out Rapid Coastal Zone Assessment Surveys to identify coastal historic assets and the risks to them. See our current coastal research pages for more information.