If you look down at our planet from outer space, most of
what you see is water; 71% of the planet's surface is
covered by ocean and it is because of this that the Earth is
sometimes called "the water planet". Only about
three-tenths of our globe is covered with land.
The ocean wraps the globe and is divided into four major
regions: the Atlantic Ocean, the Pacific Ocean, the Indian
Ocean and the Arctic Ocean. Some scientists consider the
waters around Antarctica to be a separate, fifth ocean as
well. These oceans, although distinct in some ways, are all
interconnected; the same water is circulated throughout them
If all the continents were crammed into one corner of the
Earth, the vast extent of the world ocean could easily be
seen. In reality, of course, the continents are not bunched
together as shown in the figure to the right, but instead
are spread out over the entire Earth's surface. Most
oceanographers, however, believe that a long time ago in the
Earth's geologic history all of the continents were once
grouped closely together in much the same manner.
of the Earth's surface is ocean.
Begin your exploration here looking at the sea:
Features of the Ocean
Facts about the oceans and diagrams showing the
main features found on the ocean floor.
Oceans have been created and then destroyed.
Find out how the continents have moved throughout
The oceans are always losing and gaining water
in a never ending process called the hydrologic
Vignettes of the four oceans and some of their