A new study has revealed that the famous white cliffs of Dover are eroding ten times faster than they have been over the last few thousand years.
Over the past 150 years, researchers have observed a 22 to 32 centimetres per year rate of erosion at Beachy Head and Seaford Head in East Sussex, but they calculate that in the past 7,000 years, the erosion rate was only two to six centimetres per year.
To estimate the rate of erosion, the research team, led by Dr. Martin Hurst from the University of Glasgow, examined the rock platform under the cliffs, looking for an isotope of beryllium that is formed on the top metres of rock when exposed to the cosmic rays that enter earth’s atmosphere from space. By measuring these levels, they were able to give an estimated timetable of the cliff’s disappearance.
“Our coasts are going to change in the future as a result of sea-level rise and perhaps increased storminess, and we want this work to inform better forecasts of erosion,” Hurst told the BBC.
Hurst and his team also mentioned how, in spite of conservation efforts, changes in landscape are permanent.
“The UK cannot leave the issue of cliff erosion unresolved in the face of a warming world and rising sea levels. Cliff erosion is irreversible; once the cliffs retreat, they are gone for good,” said Dr Dylan Rood from Imperial College London to the BBC.