Nearly a fifth of National Trust sites could be at high risk of climate-related hazards in the next 40 years, according to new research by the conservation charity.
The information is based on a map that the trust has developed to show the threat climate change poses to the monuments, coastlines, rural locations and historic properties it looks after in England, Wales and Northern Ireland. The map, which is based on a worst-case model of no intervention on emissions before 2060, is intended to identify risks such as flooding, landslides, coastal erosion and extreme heat and humidity so that the trust can then intervene.
“This map is a game changer in how we face the threat climate change poses to the places we care for,” said Harry Bowell, the National Trust director for land and nature. “While the data draws on a worst-case scenario, the map paints a stark picture of what we have to prepare for. But by acting now, and working with nature, we can adapt to many of these risks.”
Kate Roberts, Cadw’s head of historic environment, said: “The impact of climate change, and in particular the extreme weather events that we are experiencing with increasing frequency, are one of the most significant threats facing our historic environment. Our actions today determine the historic environment that future generations will experience. Knowing how and where to focus our resources is challenging which is why research such as this is so critical.”
The National Trust said it is already taking measures to try and tackle the threat posed by climate change by planting or establishing 20 million trees and becoming carbon net zero by 2030. The charity is also looking at how its historic buildings and collections can be better protected from extreme weather conditions, including an increase in pests.
The trust's research found that, assuming there was no intervention on emissions before 2060, the number of its sites at high or medium risk of climate related hazards could increase from 20,457 (30%) in 2020 to 47,888 (71%) in 2060 out of a total 67,426 sites.
And the number of National Trust sites in the highest threat level area could rise from 3,371 (5%) to 11,462 (17%) in the same period.
The trust is already dealing with a number of challenges at its sites caused by climate change. At Lyme Park in Cheshire, regular long dry spells followed by heavy downpours has led to increased flooding. A major flood in July 2019 caused significant damage, as the lake overflowed and spread more than 25 tonnes of debris across the garden.
There are regular landslides on the coastline around the Giants Causeway in Northern Ireland as a result of increased rainfall. Eighty miles away, Mount Stewart has worked hard over the past decade to tackle the effects of coastal erosion partly due to rising sea levels around the shores of Strangford Lough.
In Wales, the 16th-century listed farmhouse of Dyffryn Mymbyr in Snowdonia has mitigated against the impact of increased heavy rainfall by installing “slate hanging” on the exposed end of the building to protect it.