From Irish Weather Online
An underwater landslide off the coast of Cornwall, England, caused ripples along the country’s southwest coastline on Monday.
The effects of the landslide were witnessed along the coastline from Penzance to Portsmouth when the tide suddenly shifted up to 50-metres in a matter of minutes.
This reminds me of a something I came across about Kilmore Quay in 1854, I think..
http://books.google.ie/books?id=oHC7AAA ... #v=onepage&
and from The Kilmore Parish Journal.
“We are indebted to Mr. William Campbell the celebrated diver
who has done so much for the improvement of the New Pier
of Kilmore by blasting and removing the rocks which impede
its entrance, for the following account of an extraordinary
phenomenon witnessed there on Saturday evening Sept. 16th.
I was, (writes Mr Campbell) in one of our four boats seeking
after some implements and not looking seawards, when on a
sudden I heard a mighty rush of water against the back of a Pier,
and in a moment came sweeping round the Pier head, full three
feet high and abreast. It was within one hour and a half of low
water at the time. The inner dock was crowded with the small
sailing craft of the place, and quite dry – the tide being no more
that four hours on ebb. In less than five minutes every boat was
afloat, and we had high water. In five minutes more the water
ebbed again to the lowest spring tide. This was repeated seven
times in the course of two hours and a half. St. Patrick’s bridge
was alternately dry and covered to the extent of a mile, and the
sea formed a cascade from the end of it, the influx appearing to
come from the east. At the same time the sea was not by any
means rough or heaving. Standing on the top of the parapat
(sic) wall of the Pier, I could descry two different currents
running parallel, and counter currents to these quite visible, the
discoloured water running east at a rate of ten or twelve miles
an hour, and the intervening water, of the original green hue, as
is stationary. These tide currents were as far out as the shore of
the Saltee Islands. I can only compare the current to the opening
of a sluice gate. There was no damage done to any of the craft
more than the bursting of a few warps. Had the occurrence taken
place at the period of high water the result would have been
complete overflow of the land in the district, and consequent
immense loss.
We have often heard old people of that place say that on the
Sunday after Lisbon was destroyed by the earthquake of 1st.
November 1755, the day being remarkably fine, the sea at
Kilmore suddenly rose and fell in like manner. This occurrence
the other day being owing, no doubt, to some similar and
distant cause.”
