'Significant' landslide risk at pretty Welsh bay as our climate warms

Surrounding cliffs have been scarred by multiple mud slumps already, as Andrew Forgrave reports

- 

ON A dreary morning in early 2001, visitors huddled in their cars overlooking the majestic sweep of Nefyn bay on the Llŷn Peninsula. On the cliffs above them, a series of deep-seated substrate failures were about to have catastrophic consequences.

As the cliffside gave way, following heavy rain, two successive landslips engulfed seven vehicles in thick mud, pushing two of them at least 40ft down onto the beach.

A 58-year-old woman died and her husband was seriously injured.

The two landslips occurred within minutes of each other just after 11.30am on Tuesday, January 2. In their path was a parking area on Lon y Traeth, an access road which winds down to the beach.

The coastal strip running from Nefyn to Porthdinllaen, Gwynedd, has suffered multiple landslides before and since. This week, a boathouse near Nefyn's breakwater was destroyed by a mudslide which may have damaged other properties nearby.

Scientists believe the area's unstable cliffs, in places 200ft high, have been storing up problems ever since the end of the last Ice Age.

As the Irish Sea ice retreated some 17,000-25,000 years ago, it laid down a "succession of glacial and proglacial deposits" on the northern Llŷn Peninsula, according to the British Geological Survey (BGS).