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OCEAN FACTS

See the Sea.org

OCEAN GEOGRAPHY

·         There are 328,000,000 cubic miles of seawater on earth, covering approximately 71 percent of earth's surface.

·         By volume, the ocean makes up 99 percent of the planet's living space- the largest space in our universe known to be inhabited by living organisms.

  • About 97 percent of all water on earth is in our oceans, 2 percent is frozen in our ice caps and glaciers, less than 0.3 percent is carried in the atmosphere in the form of clouds, rain, and snow. All of our inland seas, lakes and channels combined add up to only 0.02 percent of earth's water.
  • The Antarctic Ice Sheet is almost twice the size of the United States.
  • Earth's ocean is made up of more than 20 seas and four oceans: Atlantic, Indian, Arctic, and Pacific, the oldest and the largest.
  • The ocean accounts for 0.022 percent of the total weight of earth, weighing an estimated 1,450,000,000,000,000,000 short tons (1 short ton = 2,000lbs).
  • The average worldwide ocean depth is about 12,460 feet (3,798 meters), with the deepest point of 36,198 feet (11,033 meters) which is located in the Mariana Trench in the Pacific Ocean; the tallest mountain, Mount Everest, measures 29,022 feet (8,846 meters). If Mount Everest were to be placed into the Mariana Trench it would be covered with sea water more than a mile (1.5 km ) deep.
  • Although Mount Everest is often called the tallest mountain on Earth, Mauna Kea, an inactive volcano on the island of Hawaii, is actually taller. Only 13,796 feet of Mauna Kea stands above sea level, yet it is 33,465 feet tall if measured from the ocean floor to its summit
  • A slow cascade of water beneath the Denmark Strait sinks 2.2 miles; more than 3.5 times farther than Venezuela's Angel Falls, the tallest waterfall on land.
  • Earth's largest continuous mountain chain is the Mid-Ocean Ridge, stretching for 40,000 miles, rising above the surface of the water in a few places, such as Iceland. It is four times longer than the Andes, Rocky Mountains, and Himalayas combined.
  • Ninety percent of all volcanic activity occurs in the oceans. In 1993, scientists located the largest known concentration of active volcanoes on the sea floor in the South Pacific. This area, the size of New York State, hosts 1,133 volcanic cones and seamounts. Two or three could erupt at any moment.
  • The highest tides in the world are at the Bay of Fundy, which separates New Brunswick from Nova Scotia. At some times of the year the difference between high and low tide is 53 feet 6 inches, the equivalent of a five-story building.
  • Canada has the longest coastline of any country, at 56,453 miles or around 15 percent of the world's 372,384 miles of coastlines.
  • In 1958, the United States Coast Guard icebreaker East Wind measured the world's tallest known iceberg off western Greenland. At 550 feet it was only 5 feet 6 inches shorter than the Washington Monument in Washington, D.C.
  • The volume of the Earth's moon is the same as the volume of the Pacific Ocean.

THE WEATHER MAKER

  • The ocean determines climate and plays a critical role in Earth's habitability. Most of the solar energy that reaches the Earth is stored in the ocean and helps power oceanic and atmospheric circulation. In this manner, the ocean plays an important role in influencing the weather and climatic patterns of the Earth.
  • Two hundred million years of recorded geologic and biologic history of the Earth are found in the ocean's floor. By studying ocean sediments, scientists can learn about ancient climate, how it changed, and how better to predict our own climate.
  • The top 10 feet of the ocean hold the same amount of thermal energy as exists in the entire atmosphere.
  • El NiZo, a periodic shift of warm waters from the western to eastern Pacific Ocean, has dramatic effects on climate worldwide. In 1997-1998, the most severe El NiZo of the century created droughts, crop failures, fires, torrential rains, floods, landslides--total damages were estimated at more than $90 billion (United Nations)
  • Undersea earthquakes and other disturbances cause tsunamis, or great waves. The largest recorded tsunami measured 210 feet above sea level when it reached Siberia's Kamchatka Peninsula in 1737.

OUR USE OF THE OCEAN

  • Substances from marine plants and animals are used in scores of products, including medicine, ice cream, toothpaste, fertilizers, gasoline, cosmetics, and livestock feed.
  • Examine the foods in your own kitchen and you may find the terms "alginate" and "carrageenan" on the labels. Carrageenans are compounds extracted from red algae that are used to stabilize and jell foods and pharmaceuticals. Brown algae contain alginates that make foods thicker and creamier and add to shelf life. They are used to prevent ice crystals from forming in ice cream. Alginates and carrageenans are often used in puddings, milkshakes, and ice cream. The commonly used color additive beta-carotene often comes from green algae as well as many vegetables, including carrots.  Many people don't realize that kelp is harvested like wheat; a substance called algin is extracted and is used in lipstick, toothpaste and ice cream. You might be wearing kelp right now, since it is used in the dyes that color our clothes.
  • Oils from the orange roughy, Hoplostethus atlanticus, a deep-sea fish from New Zealand, are used in making shampoo.
  • The remains of diatoms, algae with hard shells, are used in making pet litter, cosmetics, pool filters and tooth polish.
  • The ocean holds immense quantities of protein. The total annual commercial harvest from the seas exceeds 85 million metric tons. Fish is the biggest source of wild or domestic protein in the world.
  • Since the architecture and chemistry of coral are very close to human bone, coral has been used to replace bone grafts in helping human bones to heal quickly and cleanly.
  • Horseshoe crabs have existed in essentially the same form for the past 135 million years. Their blood provides a valuable test for the toxins that cause septic shock, which previously led to half of all hospital-acquired infections and one-fifth of all hospital deaths.
  • Over 90 percent of trade among countries is carried by ships. 
  • The ocean is a source of mineral deposits, including oil and gas.
  • About half the communications between nations are via underwater cables. 
  • Many nations' battles have been fought on or under the water. 
  • Knowing oceanography can enhance the conditions for trade, communications, and defense.

OUR MISUSE OF THE OCEAN

  • In 1993, United States beaches were closed or swimmers advised not to get in the water over 2,400 times because of sewage contamination. The problem is even worse than the numbers indicate: there are no federal requirements for notifying the public when water-quality standards are violated, and some coastal states don't monitor water at beaches.
  • The largest amount of oil entering the ocean through human activity is the 363 million gallons that come from industrial waste and automobiles. When people pour their used motor oil into the ground or into a septic system, it eventually seeps into the groundwater. Coupled with industrial waste discharged into rivers, oil becomes part of the run-off from waterways that empty into the ocean. All of this oil impacts ocean ecosystems.
  • The Coast Guard estimates that for United States waters, sewage treatment plants discharge twice as much oil each year as tanker spills.
  • Animals may perish when the oil slicks their fur or downy feathers, decreasing the surface area so they are no longer insulated from the cold water. Or the animals may ingest the oil, then become sick or unable to reproduce properly.
  • Each year industrial, household cleaning, gardening, and automotive products are added as water pollutants. About 65,000 chemicals are used commercially in the United States today, with about 1,000 new ones added each year. Only about 300 have been extensively tested for toxicity.
  • It is estimated that medical waste that washed up onto Long Island and New Jersey beaches in the summer of 1988 cost as much as $3 billion in lost revenue from tourism and recreation.
  • The most frequently found item in beach cleanups are pieces of plastic. The next four items are plastic foam, plastic utensils, pieces of glass and cigarette butts.
  • Lost or discarded fishing nets keep on fishing. Called "ghost nets," this gear entangles fish, marine mammals, and sea birds, preventing them from feeding or causing them to drown. As many as 20,000 northern fur seals may die each year from becoming entangled in netting.
  • The Mississippi River drains more than 40 percent of the continental United States, carrying excess nutrients into the Gulf of Mexico. Decay of the resulting algae blooms consumes oxygen, kills shellfish and displaces fish in a 4,000 square mile bottom area off the coast of Louisiana and Texas, called the "dead zone."
  • The zebra mussel is the most famous unwanted ship stowaway, but the animals and plants being transported to new areas through ship ballast water is a problem around the world. Poisonous algae, cholera, and countless plants and animals have invaded harbor waters and disrupted ecological balance.
  • There are 109 countries with coral reefs. Reefs in 90 of them are being damaged by cruise ship anchors and sewage, by tourists breaking off chunks of coral, and by commercial harvesting for sale to tourists.
  • One study of a cruise ship anchor dropped in a coral reef for one day found an area about half the size of a football field completely destroyed, and half again as much covered by rubble that died later. It was estimated that coral recovery would take fifty years.
  • Egypt's High Aswan Dam, built in the 1960s to provide electricity and irrigation water, diverts up to 95 percent of the Nile River's normal flow. It has since trapped more than one million tons of nutrient rich silt and caused a sharp decline in Mediterranean sardine and shrimp fisheries.
  • The United Nations Food and Agriculture Organization estimates that of the seventeen major fisheries areas in the world, four are depleted and the other thirteen are either fished to capacity or overfished.
  • Commercial marine fisheries in the United States discard up to 20 billion pounds of non-target fish each year-- twice the catch of desired commercial and recreational fishing combined. Worldwide this adds up to a staggering 60 billion pounds each year!!
  • With only 4.3 percent of the world population, Americans use about one-third of the world's processed mineral resources and about one-fourth of the world's non-renewable energy sources, like oil and coal.

FACTS ABOUT OCEAN LIFE

  • Life began in the seas 3.1 billion to 3.4 billion years ago. Land dwellers appeared 400 million years ago; a relatively recent point in the geologic time line.
  • The blue whale, Balaenoptera musculus, is the largest known animal ever to have lived on sea or land. They can reach over 110 feet and weigh almost 200 tons (more than the combined weight of 50 adult elephants). The blue whale's blood vessels are so broad that a full-grown trout could swim through them, and the heart is the size of a small car.
  • The oarfish, Regalecus glesne, is the longest bony fish in the world. With its snakelike body, sporting a magnificent red fin along its 50-foot length horselike face and blue gills, it accounts for many sea-serpent sightings
  • Green turtles can migrate more than 1,400 miles to lay their eggs.
  • Bluefin tuna, Thunnus thynnus, are among the largest and fastest marine fish. An adult may weigh 1,500 pounds and swim up to 55 miles per hour.
  • Penguins "fly" underwater at up to 55 miles per hour.
  • A group of herring is called a seige. A group of jelly fish is called a smack.
  • Many fish can change sex during the course of their lives. Others, especially rare deep-sea fish, have both male and female sex organs.
  • Giant kelp, the fastest growing plant in the ocean, can grow up to 2 feet per day. Under optimal conditions, giant kelp can grow to a length of more than 100 feet in little more than a year and can grow to a maximum of 200 feet. 
  • Hydrothermal vents, fractures in the sea floor that spew sulphur compounds, support the only complex ecosystem known to run on chemicals, rather than energy from the sun.

OCEAN PHYSICS AND CHEMISTRY

  • At the deepest point in the ocean the pressure is more than 8 tons per square inch, or the equivalent of one person trying to hold-up 50 jumbo jets against the force of gravity.
  • The major ions in seawater are Na+, Mg2+, Ca2+, K+, Sr2+, Cl-, SO42- (sulfate), HCO3- (bicarbonate), Br-, B(OH)3 (boric acid), and F-. Together, they account for almost all of the salt in seawater.
  • At 39 degrees Fahrenheit (3.89 degrees Celsius), the temperature of almost all of the deep ocean is only a few degrees above freezing.
  • If extracted, it is estimated that all the gold suspended in the world's seawater would give each person on Earth 9 pounds.
  • If the ocean's total salt content were dried, it would cover the continents to a depth of 5 feet.
When nitrogen and phosphorus from sources such as fertilizer, sewage and detergents enter coastal waters, oxygen depletion occurs. One gram of nitrogen can cause enough organic growth to require 15 grams of oxygen to decompose the resulting vegetation. A single gram of phosphorus will deplete about one hundred grams of oxygen.
Samedi 06 Octobre 2007 à 18h51 dans Les océansPoster un commentaire
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