Page 82 - (DK) Ocean - The Definitive Visual Guide

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HUMAN IMPACT
SURVIVING THE
OLD SOW

The Old Sow has caused about
a dozen fatalities from drowning
over the past 200 years. Most of
these involved mariners who
strayed too close to the whirlpool
in small rowboats or sailboats.
In recent times, a few people in
powerboats have had anxious
experiences when their engines
have stalled. Experienced
mariners advise that if caught
MINI-VORTEX in a whirlpool, the priority is
This mini-whirlpool, about 20 ft (6 m) wide to keep the boat on an even keel
and 16 in (50 cm) deep, would be called a and avoid getting swamped. Most
“piglet” by experienced Old Sow watchers. objects floating in a stable position
Sometimes, several of these small vortices will eventually spin clear.
occur, rather than a single large whirlpool.

ATLANTIC OCEAN NORTHWEST and by far the largest in the Americas. between different islands converge seamounts, so as they reach their
Passamaquoddy Bay is at the lower during the ebb tide or diverge maximum speed of up to 17 mph
The Old Sow end of the Bay of Fundy, which is during the flood tide. As they flow, (28 km/h), the whole sea surface in
famous for its strong tides. The Old these currents encounter underwater this area becomes rough and disordered.
Whirlpool Sow, when it appears, is located at a obstructions, such as ledges and small Typical disturbances include standing
spot where waves, troughs (long depressions in the
FEATURES
Tidal race, small various tidal surface), and “boils” (smooth circular
whirlpools, occasional streams flowing areas where water spouts up from deep
large whirlpool through the below). Occasionally and unpredictably,
TIMING channels the Old Sow itself appears, forming a
Four times daily
vortex that can be 100 ft (30 m) wide
COASTAL SETTING and 10 ft (3 m) deep. More often, one
LOCATION Off the southern tip of Deer Island, or several smaller vortices, known
New Brunswick, Canada The Old Sow
develops between locally as piglets, appear. As with all
Situated at the southern end of Deer Island (top) tidal disturbances, these phenomena
Passamaquoddy Bay on the US– and Moose Island are more powerful during a spring
Canada border, the Old Sow is one of in Maine, USA tide, which occurs a day or two
the largest whirlpools in the world, (foreground). after a full or new moon.

ATLANTIC OCEAN NORTHEAST a broad, submerged ledge of rock the Lofoten Maelstrom is marked on PEOPLE
between two of the Lofoten Islands. many historical charts as an enormous
Lofoten Maelstrom These flows result from large sea-level and fearsome whirlpool. In 1997, a JULES VERNE
differences that develop four times a detailed study of tidal currents in the
FEATURES day between the Norwegian Sea and vicinity of the island of Mosken found
Tidal race and large, the Vestfjord on the eastern side of the that the reality is somewhat different. The French novelist Jules Verne
weak eddy (1828-1905) made reference to
Lofoten Islands. The word “maelstrom” Although some strong tidal currents
TIMING originates with the tidal phenomena were measured, no obvious large the Lofoten Maelstrom in his tale
Four times daily of undersea exploration, Twenty
in this area, and is derived from the whirlpool, with a vortex, was detected. Thousand Leagues Under the Sea.
Nordic word male, meaning “to Instead, the researchers found a weak At the end of the novel, Captain
LOCATION Between Lofoten Point and Mosken in the grind.” In Norse mythology, the eddy, about 4 miles (6 km ) in diameter,
Lofoten Islands, off northwest Norway Maelstrom was the result of a large to the north of Mosken. This eddy Nemo and his submarine,
Nautilus, are sucked down into
salt-grinding millstone on the floor develops twice a day during the flood the whirlpool, “whose power of
Also known as the Moskenstraumen, of the Norwegian Sea, which sucked tide, when it moves in a clockwise attraction extended to a distance
the Lofoten Maelstrom is a complex water into its central hole as it turned. direction, and twice on the ebb tide, of twelve miles,” suffering an
pattern of sea-surface disturbances First described by the Greek explorer when it moves slightly farther north unknown fate.
caused by tidal flows of water over Pytheas in the 3rd century bc, and goes counterclockwise.

INTRODUCTION TIDAL DISTURBANCE

For centuries, the Lofoten Maelstrom had
a reputation as one of the world’s most
powerful tidal phenomena.