December 16, 1910 Tsunami: SW England, United Kingdom

Reference #14268:

A storm occurred on 16 December 1910, accompanied by gale-force winds and both coastal and river flooding over a wide area of southern Britain (The Times 1910). Much damage was caused to sea defenses by storm surge and wave action at a number of locations during the day (see, for example, Cundy and others 2002); but Ilfracombe in North Devon, on the Bristol Channel coast, was hit by a unique large wave. The local Ilfracombe Gazette and Observer carried the headlines “The Tidal Wave. Terrible Havoc. Enormous Damage!” ( IGO 1910). High tide at Ilfracombe occurred at 5:24 p.m., and the wave reportedly struck between 6:10 and 6:15 p.m. The U.K. synoptic chart for that day, published in The Times on 17 December, indicated that by 6:00 p.m. the 979-millibar storm depression lay over northeast England and the North Sea, that pressure over southwest England had increased to 992 millibars, with the “bar rising steadily,” and that a westerly gale maintained "rough" seas. A wind record for 6:00 p.m. at Bristol on 16 December, from the National Meteorological Archive, indicated a Force 7 (13.9-17.1 meters per second on the Beaufort Scale) southwesterly, with pressure at approximately 986 millibars.

Because storm surges tend to occur below an atmospheric depression, these data suggest that the wave at Ilfracombe is unlikely to have been surge related, for it hit sometime after the depression had passed. Moreover, eyewitness reports suggested that the wave had characteristics of a tsunami. Indeed, the local residents were so astounded by the occurrence that the Ilfracombe Gazette and Observer produced a souvenir pamphlet containing eyewitness reports and photographs ( IGO 1910a).

An interesting account came from a gentleman who “saw two cross waves meet…and rose like a mountain….The most remarkable thing was that scarcely any wind was blowing in shore at the time. I have seen rougher seas scores of times,” he added, “but it was one wave that did the damage….I should think that the whole of the damage along the coast, practically speaking, was done by that single wave”

The wave produced geomorphological effects, including erosion, where “large ruts, three feet [nearly 1 meter] deep, were dug out of the concrete” by the wave ( IGO), and cavities appeared in the north side of the pier ( IC 1910), cavities that resembled the erosion of bedrock by tsunamis described elsewhere (Bryant and Young 1996).

A report in the 16 December Ilfracombe Gazette and Observer suggested that two waves struck several minutes apart, but most other accounts mentioned only one wave.

Although no records of seismic activity exist, the Ilfracombe wave appears to have possessed the characteristics of a long-period tsunami wave because it rose abruptly as it reached the shore to an anomalously large height and then progressed across a distance of approximately 100 meters, through buildings and up the footslopes of the hills behind.

Reference #14269:

On the 16 December 1910, a wave struck Ilfracombe in the Bristol Channel, causing large ruts to be ‘dug out’ of concrete, which resembled coastal erosion by tsunamis elsewhere. The wave struck after a storm depression passed over, so this is unlikely to be a storm surge or a meteotsunami. The newspaper reports differ on whether there was a single wave or a few waves. All of this makes it doubtful that the wave was a meteotsunami, but more likely a long period swell.