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Rogue Waves
continue to baffle meteorologists
100'
Rogue Waves
Experts
Baffled by Giant Walls Of Water
Rogue waves
are the stuff of legend and maritime myth: Giant waves, taller
than highrise buildings, that rise out of calm seas. For years
scientists and marine experts have dismissed such stories as
superstition.
Walls of water
do not rise out of the blue, they said. But now research has
revealed that 'killer waves' do exist and regularly devastate
ships around the world. They defy all scientific understanding
and no craft is capable of withstanding their impact.
Rogue waves
in the past have been ignored and regarded as rare events, now
we are finally getting a handle on them and finding out how
common they are. These mammoth events are not tidal waves or
tsunamis, however. Nor are they caused by earthquakes or landslides.
They are single, massive walls of water that rise up - for no
known reason - and destroy dozens of ships and oil rigs every
year.
The story of
the super-tanker Munchen is a classic example. She was one of
the biggest ships ever built - the length of two-and-a-half
football pitches - and unsinkable, it was claimed. But on 7
December, 1978, the pride of the German merchant navy, en route
to America, disappeared off the face of the earth. All that
was found of the Munchen and her 26 crew was a lifeboat that
had suffered an incredible battering.
Something extraordinary
had destroyed the ship, concluded an official inquiry, which
dismissed the Munchen's sinking as a highly unusual event that
had no implications for other forms of shipping. Now scientists
believe this calm assurance may be dangerously misguided. The
destruction of the Munchen was anything but uncommon. Ships
are going down all the time. If you read the maritime press
there is a boat going down at least once a month, with the loss
of crew usually measured in dozens of lives. In the past, bad
maintenance or poor seamanship were blamed. Now scientists suspect
the truth may be more bizarre.
It is known
that the Queen Mary was hit by a 75ft wall of water while carrying
15,000 troops in December 1942. The ship came within an ace
of capsizing. Only a few years ago the British superliner Oriana
was struck by a 70ft wave that smashed windows and sent water
cascading through the ship, swamping six of its 10 decks.
These giant
waves cannot be predicted by standard meteorology. Waves - even
in the worst of storms - should not reach much more than 40ft.
The fact that walls of water up to 100ft are being observed
regularly suggests that something is worryingly wrong with meteorology
theory.
Waves are normally
caused by high winds whipping over the sea surface, but the
origin of the freak waves baffles scientists. One theory suggests
that waves and winds heading straight into powerful ocean currents
may cause these huge walls of water to rise up out of the deep.
Another suggests that, under certain conditions, waves can become
unstable and start to suck in energy from neighbouring waves
and so grow massively and rapidly.
Researchers
are still arguing over these ideas, but what is indisputable
is the fact that the design of modern ships is inadequate for
dealing with the freak waves.
Waves within
waves (up to 50 meters high):
As well as stormy surface waves, the undersea world experiences
its own kind of rough water. Internal waves with heights of
up to 50 metres and wavelengths of more than a kilometre can
occur at the boundaries of different water layers. There may
be no visible sign on the surface but marine life - as well
as oil drilling or submarine operations can be disrupted.
Satellite instruments can detect clues to the movement of internal
waves contained within the smaller waves on the surface.
Another theory is that waves coming
from different swell producing areas may join together and produce
a wave which is the sum of the hieght of the 2 colliding waves.
EG two 6 feet waves joining to produce one 12 feet wave.
Other Resources on waves
Wave
Forecasting Information and how waves are made
Rip
current information
what
waves are and how they behave
some real detailed and technical information on waves
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