Whirlpool

A whirlpool is a body of rotating water produced by opposing currents or a current running into an obstacle. Small whirlpools form when a bath or a sink is draining. More powerful ones in seas or oceans may be termed maelstroms. "Vortex" is the proper term for a whirlpool that has a downdraft.
In narrow ocean straits with fast flowing water, whirlpools are often caused by tides. Many stories tell of ships being sucked into a maelstrom, although only smaller craft are actually in danger. Smaller whirlpools appear at river rapids and can be observed downstream of artificial structures such as weirs and dams. Large cataracts, such as Niagara Falls, produce strong whirlpools.
Notable whirlpools.
Saltstraumen.
Saltstraumen is a narrow strait located close to the Arctic Circle, south-east of the city of Bodø, Norway.
It has one of the strongest tidal currents in the world. Whirlpools up to in diameter and in depth are formed when the current is at its strongest.
Moskstraumen.
Moskstraumen or Moske-stroom is an unusual system of whirlpools in the open seas in the Lofoten Islands off the Norwegian coast. It is the second strongest whirlpool in the world with flow currents reaching speeds as high as . This is supposedly the whirlpool depicted in Olaus Magnus' map, labeled as "Horrenda Caribdis" (Charybdis).
The Moskstraumen is formed by the combination of powerful semi-diurnal tides and the unusual shape of the seabed, with a shallow ridge between the Moskenesøya and Værøy islands which amplifies and whirls the tidal currents.
The fictional depictions of the Maelstrom by Edgar Allan Poe, Jules Verne, and Cixin Liu 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 . Poe described this phenomenon in his short story "A Descent into the Maelstrom," which during 1841 was the first to use the word "maelstrom" in the English language; in this story related to the Lofoten Maelstrom, two fishermen are swallowed by the maelstrom while one survives.
Corryvreckan.
The Corryvreckan is a narrow strait between the islands of Jura and Scarba, in Argyll and Bute, on the northern side of the Gulf of Corryvreckan, Scotland. It is the third-largest whirlpool in the world. Flood tides and inflow from the Firth of Lorne to the west can drive the waters of Corryvreckan to waves of more than , and the roar of the resulting maelstrom, which reaches speeds of , can be heard away. Though it was classified initially as non-navigable by the Royal Navy it was later categorized as "extremely dangerous".
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 with evidence of being dragged along the bottom for a great distance.
Other notable maelstroms and whirlpools.
Old Sow whirlpool is located between Deer Island, New Brunswick, Canada, and Moose Island, Eastport, Maine, USA. It is given the epithet "pig-like" as it makes a screeching noise when the vortex is at its full fury and reaches speeds of as much as . The smaller whirlpools around this Old Sow are known as "Piglets".
The Naruto whirlpools are located in the Naruto Strait near Awaji Island in Japan, which have speeds of .
Skookumchuck Narrows is a tidal rapids that develops whirlpools, on the Sunshine Coast, Canada with current speeds exceeding .
French Pass () is a narrow and treacherous stretch of water that separates D'Urville Island from the north end of the South Island of New Zealand. During 2000 a whirlpool there caught student divers, resulting in fatalities.
A short-lived whirlpool sucked in a portion of the Lake Peigneur in Louisiana, United States after a drilling mishap on 20 November 1980. This was not a naturally occurring whirlpool, but a disaster caused by underwater drillers breaking through the roof of a salt mine. The lake then drained into the mine until the mine filled and the water levels equalized, but the formerly deep lake was now deep. This mishap resulted in the destruction of five houses, loss of nineteen barges and eight tug boats, oil rigs, a mobile home, trees, acres of land, and most of a botanical garden. The adjacent settlement of Jefferson Island was reduced in area by 10%. A crater across was left behind. Nine of the barges, which had sunk, later resurfaced after the whirlpool subsided.
A more recent example of an artificial whirlpool that received significant media coverage occurred during 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.
Dangers.
Powerful whirlpools have killed unlucky seafarers, but their power tends to be exaggerated by laymen. One of the few reports of large ships ever being sucked into a whirlpool is from the fourteenth century Mali Empire ruler Mansa Musa, as reported by a contemporary, Al-Umari:
Tales like those by Paul the Deacon, Edgar Allan Poe, and Jules Verne are entirely fictional.
However, temporary whirlpools caused by major engineering disasters, such as the Lake Peigneur disaster, have been recorded as capable of submerging medium-sized watercraft such as barges and tugboats.
In literature and popular culture.
Besides Poe and Verne, another literary source is of the 1500s, Olaus Magnus, a Swedish bishop, who had stated that a maelstrom more powerful than the one written about in The Odyssey sucked in ships which sank to the bottom of the sea, and even whales were pulled in. Pytheas, the Greek historian, also mentioned that maelstroms swallowed ships and threw them up again.
The monster Charybdis of Greek mythology was later rationalized as a whirlpool, which sucked entire ships into its fold in the narrow coast of Sicily, a disaster faced by navigators.
During 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:
Three of the most notable literary references to the Lofoten Maelstrom date from the nineteenth century. The first is a short story by Edgar Allan Poe named "A Descent into the Maelström" (1841). The second is "20,000 Leagues Under the Sea" (1870), a 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 the "Nautilus" were seen to have survived). The "Norway maelstrom" is also mentioned in Herman Melville's "Moby-Dick".
In the 'Life of St Columba', the author, Adomnan of Iona', attributes to the saint miraculous knowledge of a particular bishop who sailed into a whirlpool off the coast of Ireland. In Adomnan's narrative, he quotes Columba saying
The Corryvreckan whirlpool plays a key role in the 1945 Powell-Pressburger film "I Know Where I'm Going." Joan Webster (Wendy Hiller), is determined to get to the fictional Isle of Kiloran and marry her fiancé. Dangerous weather delays her crossing, and her determination becomes desperation when she realizes that she is falling in love with Torquil MacNeil (Roger Livesey). Against the advice of experienced folk, she offers a young fisherman a huge sum of money to take her over. At the last moment, Torquil steps into the boat, and after a squall knocks the engine out of commission, they face the whirlpool. Torquil manages to repair the engine before the tide turns, and they return to the mainland. This part of the picture uses footage Powell filmed at Corryvreckan (tied to a mast to leave both hands free for the camera) incorporated into scenes shot in a huge tank at the studio.
In the movie "", the final battle between the "Black Pearl" and the "Flying Dutchman" takes place with both ships sailing inside a giant whirlpool which appears to be over a kilometer wide and several hundred meters deep.
Etymology.
One of the earliest uses in English of the Scandinavian word ("malström" or "malstrøm") was by Edgar Allan Poe in his short story "A Descent into the Maelström" (1841). The Nordic word itself is derived from the Dutch word "maelstrom", modern spelling "maalstroom", from "malen" ("to mill" or "to grind") and "stroom" ("stream"), to form the meaning "grinding current" or literally "mill-stream", in the sense of milling (grinding) grain.