Towns and cities across Scotland would be devastated if the country’s coastline was hit by a tsunami of the kind that happened 8,200 years ago, according to an academics’ study.
While about 370 miles of Scotland’s northern and eastern coastline were affected when the Storegga tsunami struck, the study suggests a modern-day disaster of the same magnitude would have worse consequences.
The researchers at the universities of Sheffield, St Andrews and York attributed this to denser human populations and higher sea levels that could potentially destroy seafront and port areas of Arbroath, Stonehaven, Aberdeen, Inverness and Wick, all of which have significant built-up areas less than 10 metres above sea level and directly face the sea.
The study which maps the impact of the ancient tsunami for the first time, used modelling to estimate how far the wave would have travelled inland. The estimates suggest the water could have encroached up to 18 miles inland. That distance today would probably leave a town such as Montrose, which overlooks a tidal lagoon and has a population of 12,000, completely devastated.
The Storegga tsunami, considered the largest natural disaster to have happened in the UK in the last 11,000 years, was triggered by submarine landslides in the Norwegian sea. The displaced water is believed to have inundated Doggerland, a land bridge that linked Britain, Denmark and the Netherlands across what is now the southern North Sea. The tsunami would have had a catastrophic impact on the Mesolithic populations of the time.
Luminescence dating, which measures the energy emitted after an object has been exposed to daylight, was used in the research to assess sediment and deposits from the tsunami.
By dating sediment deposits at Maryton, Aberdeenshire, the researchers were able to determine the date, number and relative power of the waves. Similar deposits have been studied all along the eastern and northern coastline of Scotland, from around Berwick-upon-Tweed to Loch Eriboll, in Sutherland, as well as along the Norwegian coast north of Bergan, and by Shetland and the Faroe Islands.
Mark Bateman, professor of geography at the University of Sheffield and the report’s lead author, said: “Although the Storegga tsunami has been known about for years, this is the first time we have been able to model how far inland from Scotland’s coastline the tsunami wave travelled, by analysing the soil deposits left by the wave over 8,000 years ago. Though there is no similar threat from [the direction of] Norway today, the UK could still be at risk from flooding events from potential volcanic eruptions around the world, such as those predicted in the Canary Islands.
“These [eruptions] would cause a similar resulting tsunami wave due to the amount of material that would be displaced by the volcano. These models give us a unique window into the past to see how the country was, and could again be, affected.”