Huge landslides became a major threat in the North of England during the record rainfall of December and the incidence of them will increase as the climate alters, a senior academic from the University of Leeds has told regional BBC news programmes.
Dr Bill Murphy, a senior lecturer in Engineering Geology, was interviewed by meteorologist Keeley Donovan on the subject for Inside Out on BBC Leeds and West Yorkshire (broadcast 22 February). Another interview on the same day for BBC Radio Leeds, in which Dr Murphy talked about hard engineering solutions to maximise protection for roads, railways and other infrastructure, was used by BBC local radio stations across the country.
The Inside Out story focused on a farmhouse near Todmorden in the Calder Valley, which has not been considered safe to live in since a wall of mud, rocks and turf descended from the moor above on Boxing Day, lodging against the building. The programme reported that 52 landslips had occurred during the recent period of extraordinary rainfall, including one that had rendered the A59 Harrogate to Skipton impassable at Blubberhouses and another blocking the Rochdale canal.
Dr Murphy, who has studied landslides and slope stability for 20 years, said that such mudslides are created when ground becomes saturated and water pressure pushes soil grains apart, causing the mass to flow. Typically they move at a speed of one or two metres a second, but some can move as fast as three or four metres in that time.
A greater number of landslides will occur as the effects of climate change intensify, with air temperatures rising and increasing amounts of rainfall making hilly regions increasingly vulnerable, he said. ‘As we see a one degree increase in temperature we can expect to see a nine per cent increase in moisture in the atmosphere. The consequence of that is that we are going to get more landslides.’