Another kind of Brexit is slowly but surely making itself felt on England’s south coast: Sussex’s chalk cliffs are apparently crumbling into the sea at an accelerating rate. according to a study by Martin Hurst of the University of Glasgow and his team. The coastline in this region has receded by 2 to 6 centimeters per year for thousands of years, but this process has accelerated by 22 to 32 centimeters per year over the past 150 years, the geoscientists explain. Coastal erosion data has only been accurately recorded since the 19th century, so Hurst and company had to use isotopic analysis to calculate past erosion. With the help of beryllium-10 it can be dated when the rocks became exposed, as is the case with the receding chalk cliffs. Using a model of coastal dynamics, the researchers obtained the slow rate of erosion since the end of the last ice age, which they were able to compare with more recent measurements.

Several factors are involved in this development: on the one hand, stronger storms have hit the Sussex coast in recent decades, and with them stronger swells, which have eaten away at the rocks. Scientists do not see a direct connection to climate change, as erosion increased significantly 150 years ago, before human-caused climate change began. Rather, human intervention in the coastal structure played a prominent role, according to the researchers. Although construction measures to the west of the most affected cliff sections would have protected the shorelines, this would also reduce the amount of sediment that had previously been washed out to sea. Normally these were deposited in front of the cliffs and widened the beach or flattened the beach plate in the sea. Consequently, the waves lost more energy when they hit the shore. Since then, the lack of material has reduced the protective effect and the waves hit the rocks with greater force, which in turn explains the greater erosion.