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The Strait of Dover could be at risk from tsunami claims an expert in oceanography at the University of Wales, Newport, in a BBC Timewatch programme to be broadcast this week.

"Tsunami strike British shores more frequently than previously considered with a group of possible tsunami events occurring throughout history in the Dover Straits," said Professor Simon Haslett, a coastal scientist whose research is featured in the programme, Britain Forgotten Floods , to be broadcast on October 4.

"The historical disasters we examined also included over 20 events associated with earthquakes along the Kent coast in the Dover Straits, along the Essex coast, Devon and Cornwall, Scotland, Pembrokeshire, the Bristol Channel and even in the Thames Estuary in London.

"They have caused damage and loss of life in the past, and pose a future threat, particularly as a consequence of climate change."

The programme will focus on research carried out by Professor Haslett and Australian tsunami expert Professor Ted Bryant which recently appeared in the international journal Natural Hazards and Earth System Sciences published by the European Geosciences Union.

They reveal that the Dover Strait regularly experiences earthquakes, such as the 4.2 magnitude earthquake that occurred in Folkestone in April 2007. When these earthquakes have occurred in the past with a higher magnitude, eye witnesses describe what could be interpreted as tsunami.

Professor Haslett, Director of the newly established Centre for Excellence in Learning and Teaching at Newport University, said, "Among other examples of Dover Straits tsunami is the one in May 1382 when a 5.75 magnitude earthquake struck that as well as causing churches to collapse on land generated waves that damaged ships in port and led contemporary writers to describe the event as a watershake or waterquake .

"Later in April 1580, a 5.8 magnitude earthquake occurred with its epicentre on the sea bed close to Calais. Giant waves were reported at the time and hundreds of people were killed when ships were sunk by the waves and the low-lying coastal land around Calais was inundated by the sea."

Following the Indian Ocean tsunami of 2004, DEFRA compiled a report of the tsunami risk in Britain, but as Professor Haslett points out the report omitted or dismissed a large number of historical flood events that might have been caused by tsunami, which limited the value of the report and perhaps underestimated the risk.

As a result, he and Professor Bryant took it upon themselves to investigate these forgotten floods so as to better inform the debate about risks from tsunami in Britain. Their research examined 21 events to hit Britain over the past 1000 years.

"If we are correct it makes tsunami a more common hazard in the UK than previously considered, making the chance of another happening again in the future a real possibility," said Professor Haslett.

"These forgotten floods may not all be tsunami, but the association of many of them to known tsunami causes, such as earthquakes and comets, does support our interpretation.

"However, any future tsunami in the UK is likely to be on a far smaller scale and more localised than the tsunami that occur in either the Pacific or Indian Oceans."

Professor Haslett added that climate change may have an unforeseen effect and increase the likelihood of tsunami, due to sea-level rise and the melting of the Greenland ice sheet, both of which have the potential for triggering undersea earthquakes and landslides that could generate massive tsunami in the North Atlantic.

"It is important to know if a flood is due to a tsunami or a storm, as storm flooding is more predictable and evasive action can be taken, whereas tsunami can occur at any time and require educating the public to respond quickly to warning signs.

"People should not, when they feel an earthquake, do as a group in Kent did in April 2007. Feeling the Folkestone earthquake they started rushing out from their houses and on to the beach for safety," said Professor Haslett.

More information about the research carried out by Professors Haslett and Bryant can be found in their article Natural Hazards and Earth System Sciences at: http://www.nat-hazards-earth-syst-sci.net/8/587/2008/nhess-8-587-2008.html