FaSEAnating!
Interesting articles about sailing, ships, and the sea.
Scientists find new life forms, tiny plankton, never seen before, in the deepest part
of the ocean.
The deepest known part of the ocean is known as the 'Challenger Deep'. You can feel the pressure on your body by diving down just a few feet underwater, the pressure
where the find was made is 1,100 times more than normal atmospheric pressure at the surface,
that’s about 16,000 pounds per square inch! There are an estimated 4,000 species of living foraminifera, inhabiting a wide range of
marine environments, mostly on the ocean bottom, though some live in the upper 300 feet
(100 metres) or so of the ocean. A few species are even found in fresh water and on land.
Japanese researcher Hiroshi Kitazato told the Associated Press. 'All the species we found
from the Challenger Deep are quite new,'. __how the ocean how trenches are formed__________________
The earths crust is like the shell of an egg is compared to the size of the egg, but the
shell has several cracks! Large plates of the shell float on the surface of the molten rock
of the earth's mantle. 1 - the epipelagic, or sunlit, zone: the top layer of the ocean where enough sunlight penetrates for
plants to carry on photosynthesis. 2 - the mesopelagic, or twilight, zone: a dim zone where some light penetrates, but not enough for
plants to grow. 3 - the bathypelagic, or midnight, zone: the deep ocean layer where no light penetrates. 4 - the abyssal zone: the pitch-black bottom layer of the ocean; the water here is almost freezing and
its pressure is immense. 5 - the hadal zone: the waters found in the ocean's deepest trenches.
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Monster ocean waves that rise out of nowhere to swallow ships and sailors are more than just mariners' tales....
The Marques was one of 39 tall ships that took part in a transatlantic race in 1984.
Shortly before dawn on Sunday, June 3, the ship sailed into a fierce squall north of Bermuda. The gusty weather was not unusual,
but the wave that slammed the vessel broadside was. Crew member Philip Sefton, 22, described it as "a freakish wave of incredible force
and size." As the ship tipped over, a second monster wave filled the Marques with water, sinking it in less than a minute.
Out of a crew of 28, only Sefton and eight others survived.
Similar accounts of freakishly high waves, or rogue waves, were once dismissed as sea lore. But no longer.
Between 1969 and 1994, rogue waves sank as many as 22 supercarriers (cargo ships more than 200 meters [656 feet] long)
and claimed more than 500 lives on board the carriers. Many cruise liners, steamships, drilling rigs, yachts, and fishing boats
have also been hit by rogues.
Eyewitnesses describe the unpredictable waves as monstrous walls of water. A rogue wave typically has a steep face
heightened by a deep trough preceding it that looks like a "hole in the sea." The biggest rogue on record dates back to 1933,
when the U.S. Navy steamship Ramapo survived a wave as tall as an 11-story building.
__MOTION IN THE OCEAN______________ How high an ocean wave gets depends on three factors: speed, or how hard the wind blows; duration, or how long the wind blows;
and fetch, or how much open water there is.
The harder and longer the wind blows and the wider the sea surface is, the bigger the waves get. And the bigger the waves,
the more wind they "catch," making them even bigger.
But why do rogues rise so high? Oceanographers have three possible explanations: The only problem with these explanations is that rogue waves are a lot higher, a lot more frequent, and a lot more widespread
than the explanations predict. Rogues have even been seen rearing like monsters out of calm seas.
Oceanographers and mathematicians are now looking beyond explanations in which small waves simply add up to form big ones.
They believe that ocean waves are much more complex than previously thought.
__CHAOTIC `FREAK'QUENCY_____________ The answer appears to be yes. So far, computer programs based on chaos theory have predicted rogue waves often and
everywhere. Al Osborne, an American physicist at the University of Turin in Italy, has applied one chaos formula to show
how ocean waves four times the average wave height can appear out of the blue and then disappear.
__'THREE SISTERS'________________ home |Fairlead |kit prices |
An ocean trench, at 36,201 feet (11,034 metres) below sea level, Challenger Deep is the
lowest part of the Pacific Ocean's Mariana Trench, located just east of the Philippines in
the Pacific Ocean Islands, nearly 7 miles (11 kilometres) down.
Several hundred foraminifera, single-celled organisms, were collected in a sample of sediment
from the Challenger Deep by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC).
Using KAIKO, JAMSTEC's remotely operated submersible vehicle.
Scientists are uncertain if the life forms adapted to living at such great depths
by migrating down into the trenches, or just adapting to the changing environment as the sea
bed sank over millions of years.
These plates bump, grind, and crash into each other, forming the earths features.
The crust over the oceans is heavier than the continental crust so when the plates collide,
the ocean plates plunge downward toward the molten mantle, while the continental plate rides
up over the top.
The underlying (subducted) oceanic plate creates a trench where it drags the edge of the
continental crust down as it descends underneath it.
Oceanographers divide the ocean into five broad zones according to how far down sunlight
penetrates:
Rogue waves are thought to begin like ordinary ocean waves--as simple ripples, or capillary waves, on the water's surface.
On calm days, a capillary wave is weaker than the water's surface tension, which pulls the wave down to the smallest possible size.
Surface tension is a force across the surface of a liquid that makes it behave like stretched elastic skin.
When a light breeze kicks up, however, the wind gets a grip on a capillary wave, giving it enough energy to form an actual wave.
* Waves coming at different speeds from different directions suddenly meet and mingle into one big rogue wave.
* Strong waves collide with fast-flowing ocean currents coming from the opposite direction, slowing down the waves so that they pile
into one another and form rogues.
* Rogue waves are simply a natural, if rare, occurrence at the high end of a wide range of wave heights.
Scientists are now using chaos theory to explain the
unpredictable and seemingly random behavior of rogue waves.
According to chaos theory, a tiny change somewhere can set off a chain of events that has a huge impact elsewhere.
The classic example of chaos theory is a butterfly beating its wings in Brazil and causing a hurricane in the United States.
Could a small change in wave height, speed, or direction create a rogue wave?
Other researchers, using different chaos equations, have arrived at similar results. Their computer programs have shown
everything from walls of water that go miles without changing speed or size to monster waves that rise and fall in minutes to gangs of
three to five rogues that travel together. Sailors call such gangs the fearsome "three sisters" phenomenon.
This new research aims to help save lives and ships by better anticipating the roguish behavior of waves. Records indicate that
average wave heights in the North Atlantic and Pacific oceans are on the rise, perhaps as a result of increased storm activity due to
global warming. That could mean that the rogue waves out there are growing steadily higher, too.