Ocean Facts

Ocean Facts
The planet earth is the only planet known to have oceans. Oceans are large amounts of saline water that make up most of a planet's water mass. While some people refer to an ocean as a sea, a sea is a body of saline water that is either completely or mostly surrounded by land. The oceans on earth, in order from smallest to largest include the Arctic Ocean, Antarctic Ocean, Indian Ocean, Atlantic Ocean and the Pacific Ocean. Less than three percent of the water on earth is freshwater - the rest is all saltwater. The combined area of the world's oceans encompasses 139 million square miles.
Interesting Ocean Facts:
The world's oceans cover approximately 70% of the surface of the earth.
There are hundreds of thousands of marine life forms known to man but it is estimated that there may actually be millions of marine life forms in existence.
The Pacific Ocean is the largest ocean on earth and covers approximately 30% of the surface of the earth.
'Pacific Ocean' means 'peaceful sea'.
The deepest known part of the world's oceans is Mariana Trench, which is located east of the Mariana Islands. It is around 11,000 meters deep at its deepest point.
There are approximately 25,000 islands in the Pacific Ocean.
The Atlantic Ocean is the second largest ocean in the world and covers more than 21% of the surface of the earth.
The Indian Ocean is the third largest ocean in the world and covers approximately 14% of the surface of the earth.
The Arctic Ocean is almost completely covered in ice in the winter.
The largest mountain range on earth is actually below the ocean's surface. It is called the Mid-Oceanic Ridge and runs from the middle of the Atlantic to the Indian and Pacific. It is more than 35,000 miles long. It makes up 23% of the surface of the earth.
Approximately 94% of the life on earth is made up of aquatic life forms.
Man has explored less than five percent of the oceans on earth.
There are volcanoes underwater in the oceans. When they erupt they don't spew lava but instead spew mud and methane. About 90% of the volcanic activity on earth occurs in the oceans.
There are underwater hot springs in the ocean that can shoot water as hot as 650 degrees Fahrenheit.
There are approximately 350 species of sharks living in the world's oceans. Of these 350 species of sharks only 32 have been known to attack people. There are another 36 species that are considered to be potentially dangerous to people.
Volcanoes, earthquakes and landslides that occur in the oceans can cause tsunamis which are large sea waves. When they reach land they can be traveling at speeds of hundreds of kilometers an hour.
Pollution in the air contributes to 33% of the toxic contaminants that land in the ocean. 44% of the contaminants that land in the ocean are from rivers and streams.
The largest living structure on earth is the Great Barrier Reef. It supports 400 species of coral and is so large it can be seen from space.

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