Oceans 11 Oceans 11 IntroductionIntroduction

• The oceans cover 71 percent of the

Earth's surface and contain 97.1 percent of the Earth's water.

•The Marianas Trench, located in the Pacific Ocean is, at a depth of 11.7 km, the deepest point on earth, even deeper than Mount Everest is tall.•The average temperature of all ocean water is about 3.5° C.

Ocean facts

More facts…More facts…•If the ocean's total salt content were dried, it would cover the continents to a depth of 5 feet.

•Algae, which is the most numerous producer in the world’s oceans, produces more than half of the world’s oxygen.

• The top ten feet of the ocean hold as much heat as our entire atmosphere

• The oceans provide 99 percent of the Earth's living space- the largest space in our universe known to be inhabited by living organisms

• More than 90% of this habitat exists in the deep sea known as the abyss

• Less than 10% of this living space has been explored by humans

• The Antarctic ice sheet that forms and melts over the ocean each year is nearly twice the size of the United States

• The average temperature of the oceans is 2ºC, about 39ºF

• Water pressure at the deepest point in the ocean is more than 8 tons per square inch, the equivalent of one person trying to hold 50 jumbo jets.

• The worlds oceans contain nearly 20 million tons of gold

• The color blue is least absorbed by seawater; the same shade of blue is most absorbed by microscopic plants, called phytoplankton, drifting in seawater

• A new form of life, based on chemical energy rather than light energy, resides in deep-sea hydrothermal vents along mid-ocean ridges

• The blue whale, the largest animal on our planet ever (exceeding the size of the greatest dinosaurs) still lives in the ocean; it's heart is the size of a Volkswagen

• More than 90 percent of the trade between countries is carried by ships and about half the communications between nations use underwater cables

• Plastic waste kills up to 1 million sea birds, 100,000 sea mammals and countless fish each year.

• Plastic remains in our ecosystem for years harming thousands of sea creatures everyday.

• More than 3.5 billion people depend on the ocean for their primary source of food. In 20 years, this number could double to 7 billion.

• The PACIFIC Ocean is the largest of the four main oceans. Although its' name means peaceful, if can be very rough!

• The ATLANTIC Ocean is the busiest. Many ships cross the Atlantic, carrying cargo between the Americas, Africa, and Europe

• A group of herring is called a seige. A group of jelly fish is called a smack.

• 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.

What is Oceanography?What is Oceanography?• Oceanography is the Oceanography is the

study of the study of the geographical, chemical, geographical, chemical, physical and biological physical and biological characteristics and characteristics and processes of the worlds processes of the worlds oceans.oceans.

Biology

Physics Chemistry

Geology

OCEANOGRAPHY

Ocean usesOcean uses

• The two most important uses of the oceans to humans are as a source of food and as transportation.

• Early ocean studies focused on mapping navigation routes for transportation and on documenting areas for catching finfish and shellfish.

Early use of the OceansEarly use of the Oceans• Remains of the discarded bones

of marine fishes, as well as fishhooks, nets, harpoons and rudimentary boats, used by stone age people, were found in Europe.These items have been dated back to about 40,000 B.C.E.

History of OceanographyHistory of Oceanography

Key Milestones:• 1831-1836: HMS Beagle – Charles

Darwin collected data which led to his theory of natural selection.

• 1872-1876: HMS Challenger – circled globe and collected extensive data on chemical composition of seawater, sediments, seafloor topography.

History of Oceanography, cont’dHistory of Oceanography, cont’dKey Milestones:• 1925-1927: Meteor – German vessel set the

standard in physical oceanographic research in the Atlantic Ocean.

• 1969-1970: CSS Hudson – first ship to circumnavigate the Americas.

• 1977: Submersible Alvin – discovered hydrothermal vents.

• 1978: Seasat-A – first satellite launched to study oceans by remote sensing.

Captain James CookCaptain James Cook• In 1768 James Cook began the first of

three famous voyages to systematically map and study the Pacific Ocean.

• He took measurements of temperature, current speed, wind speed, and the occurrence of reefs.

• He also measured depths up to 366 m with a lead weight attached to a rope.

James CookJames Cook

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HMS ChallengerHMS Challenger

• 1872-1876 • A British ship fitted to study the

physics, chemistry, biology and geology of the oceans.

• Collected numerous samples of fishes, sediments, depth and water.

• Studied the Pacific and Atlantic Oceans as well as the south Indian Ocean.

The Major OceansThe Major Oceans

Ocean Size (in km2)

Pacific 179,700,000

Atlantic 82,362,000

Indian 73,556,000

Arctic 14,090,000

• Your first assignment