Whirlpool
A whirlpool is a body of swirling water produced by the meeting of opposing currents. The vast majority of whirlpools are not very powerful. More powerful ones in seas or oceans may be termed maelstroms. Vortex is the proper term for any whirlpool that has a downdraft.
Very small whirlpools can easily be seen when a bath or a sink is draining. In oceans, whirlpools are normally caused by tides; there are few stories of large ships ever being sucked into such a maelstrom, although smaller craft are in danger.[1] Smaller whirlpools also appear at the base of many waterfalls.[2] In the case of powerful waterfalls, like Niagara Falls, these whirlpools can be quite strong. The most powerful whirlpools are created in narrow, shallow straits with fast flowing water.
Notable whirlpools
Moskstraumen
The original Maelstrom (described by Poe and others) is the Moskstraumen, a powerful tidal current in the Lofoten Islands off the Norwegian coast.[3] The Maelstrom is formed by the conjunction of the strong currents that cross the straits (Moskenstraumen) between the islands and the great amplitude of the tides, and reaches speeds of 27.8 km/h (17.3 mph)
In Norwegian, the most frequently used name is Moskenesstraumen (current of [island] Mosken).
The fictional depictions of the Maelstrom by Edgar Allan Poe and Jules Verne describe it as a gigantic circular vortex that reaches the bottom of the ocean, when in fact it is a set of currents and crosscurrents with a rate of 18 km/h.[4]
Saltstraumen
The maelstrom of Saltstraumen is the world's strongest maelstrom and is located 10 kilometres (6 mi) south-east of the city of Bodø, Norway. It reaches speeds of 37 km/h (23 mph). Its impressive strength is caused by the world's strongest tide occurring in the same location. A narrow channel connects the outer Saltfjord with its extension, the large Skjerstadfjord, causing a colossal tide which in turn produces the Saltstraumen maelstrom.
Corryvreckan
The Corryvreckan is the third-largest whirlpool in the world, and is on the northern side of the Gulf of Corryvreckan, between the islands of Jura and Scarba off the coast of mainland Scotland. Flood tides and inflow from the Firth of Lorne to the west can drive the waters of Corryvreckan to waves of over 9 metres (30 ft), and the roar of the resulting maelstrom, which reaches speeds of 18 km/h (11 mph), can be heard 16 kilometres (9.9 mi) away.
A documentary team from Scottish independent producers Northlight Productions once threw a mannequin into the Corryvreckan ("the Hag") with a life jacket and depth gauge. The mannequin was swallowed and spat up far down current with a depth gauge reading of 262 metres with evidence of being dragged along the bottom for a great distance.[5]
Other notable maelstroms and whirlpools
Old Sow whirlpool is located between Deer Island, New Brunswick, Canada, and Moose Island, Eastport, Maine, USA, and reaches speeds of up to 27.6 km/h (17.1 mph)
The Naruto whirlpools are located in the Naruto Strait near Awaji Island in Japan, which have speeds of 20 km/h (12 mph)
Skookumchuck Narrows is a tidal rapids that develops whirlpools, on the Sunshine Coast (British Columbia), Canada.
French Pass (Te Aumiti) is a narrow and treacherous stretch of water that separates D'Urville Island from the north end of the South Island of New Zealand. In 2000 a whirlpool there caught student divers, resulting in multiple fatalities.[6]
There was a short-lived whirlpool that sucked in a portion of Lake Peigneur in Louisiana, United States after a drilling mishap in 1980. This was not a naturally-occurring whirlpool, but a man-made disaster caused by breaking through the roof of a salt mine. The lake then behaved like a gigantic bathtub being drained, until the mine filled and the water levels equalized.
A more recent example of a man-made whirlpool that received significant media coverage was in early June 2015, when an intake vortex formed in Lake Texoma, on the Oklahoma–Texas border, near the floodgates of the dam that forms the lake. At the time of the whirlpool's formation, the lake was being drained after reaching its highest level ever. The Army Corps of Engineers, which operates the dam and lake, expected that the whirlpool would last until the lake reached normal seasonal levels by late July.[7]
Dangers
Powerful whirlpools have killed unlucky seafarers, but their power tends to be exaggerated by laymen.[8] There are virtually no stories of large ships ever being sucked into a whirlpool. Tales like those by Paul the Deacon, Edgar Allan Poe, and Jules Verne are entirely fictional.[9]
In literature and popular culture
Charybdis in Greek mythology was later rationalized as a whirlpool.
In the 8th century, Paul the Deacon, who had lived among the Belgii, described tidal bores and the maelstrom for a Mediterranean audience unused to such violent tidal surges:
"Not very far from this shore … toward the western side, on which the ocean main lies open without end, is that very deep whirlpool of waters which we call by its familiar name "the navel of the sea." This is said to suck in the waves and spew them forth again twice every day. … They say there is another whirlpool of this kind between the island of Britain and the province of Galicia, and with this fact the coasts of the Seine region and of Aquitaine agree, for they are filled twice a day with such sudden inundations that any one who may by chance be found only a little inward from the shore can hardly get away. I have heard a certain high nobleman of the Gauls relating that a number of ships, shattered at first by a tempest, were afterwards devoured by this same Charybdis. And when one only out of all the men who had been in these ships, still breathing, swam over the waves, while the rest were dying, he came, swept by the force of the receding waters, up to the edge of that most frightful abyss. And when now he beheld yawning before him the deep chaos whose end he could not see, and half dead from very fear, expected to be hurled into it, suddenly in a way that he could not have hoped he was cast upon a certain rock and sat him down." Paul the Deacon, History of the Lombards, i.6
Three of the most notable literary references to the Lofoten Maelstrom date from the nineteenth century. The first is the Edgar Allan Poe story "A Descent into the Maelström" (1841). The second is 20,000 Leagues Under the Sea (1870), the famous novel by Jules Verne. At the end of this novel, Captain Nemo seems to commit suicide, sending his Nautilus submarine into the Maelstrom (although in Verne's sequel Nemo and Nautilus survived). The "Norway maelstrom" is also mentioned in Herman Melville's Moby-Dick.[10]
In Adomnan of Iona's 'Life of St Columba', the saint supposedly has miraculous knowledge of a particular bishop who ran into a whirlpool off the coast of Ireland. In Adomnan's narrative, he quotes Columba saying[11]
Cólman mac Beognai has set sail to come here, and is now in great danger in the surging tides of the whirlpool of Corryvreckan. Sitting in the prow, he lifts up his hands to heaven and blesses the turbulent, terrible seas. Yet the Lord terrifies him in this way, not so that the ship in which he sits should be overwhelmed and wrecked by the waves, but rather to rouse him to pray more fervently that he may sail through the peril and reach us here.
Etymology
One of the earliest uses in English of the Scandinavian word (malström or malstrøm) was by Edgar Allan Poe in his story "A Descent into the Maelström" (1841). In turn, the Nordic word is derived from the Dutch maelstrom, modern spelling maalstroom, from malen (to grind) and stroom (stream), to form the meaning grinding current or literally "mill-stream", in the sense of milling (grinding) grain.[12]
See also
References
- ↑ 10 Magnificent Maelstroms. WebEcoist. Retrieved on 2011-10-26.
- ↑ Carreck, Rosalind, ed. (1982). The Family Encyclopedia of Natural History. The Hamlyn Publishing Group. p. 246. ISBN 0711202257.
- ↑ Encyclopædia Britannica, 1958 edition.
- ↑ B. Gjevik, H. Moe and A Ommundseb, "Strong Topographic Enhancement of Tidal Currents: Tales of the Maelstrom", University of Oslo, working paper, 5 Sep 1997. A condensed version published as Gjevik, B.; Moe, H.; Ommundsen, A. (1997). "Sources of the Maelstrom" (PDF). Nature 388 (6645): 837–838. doi:10.1038/42159.
- ↑ "Equinox: Lethal Seas". UK and US co-production by Northlight, "Lethal Seas" UK Channel 4, "Sea Twister!" US Discovery Channel, covers several notable maelstroms.
- ↑ Smith, I R (April 14, 2003). "In the matter of an inquest into the deaths of Narelle Taniko te Purei, Ricki Graeme McDonald and Michael David Welsh" (PDF). Nelson District Coroner – via Dive New Zealand.
- ↑ Smith, Chelsi (June 8, 2015). "Levels at Lake Texoma decrease; rare look at intake vortex". Sherman, TX: KXII-TV. Retrieved June 30, 2015.
- ↑ MythBusters Episode 56: Killer Whirlpool. Mythbustersresults.com. Retrieved on 2011-10-26.
- ↑ Paul the Deacon, History of the Lombards (8th century AD); Edgar Allan Poe, "A Descent into the Maelström" (1841); and Jules Verne, Twenty Thousand Leagues Under the Sea (1870).
- ↑ Herman Melville Moby-Dick Chapter 36, Wikisource.
- ↑ Adomnan of Iona. Life of St Columba. Penguin Books, 1995
- ↑ The Merriam-Webster new book of word histories. Merriam-Webster, Inc. 1991. p. 300. ISBN 978-0-87779-603-9.
Bibliography
- Baron PA, Willeke K (1986) Respirable droplets from whirlpools: measurements of size distribution and estimation of disease potential. Environ Res 39, 8–18.
External links
Wikimedia Commons has media related to Whirlpools. |