Atlantic Ocean

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Atlantic Ocean
The second largest of the world's four oceans is located between the continents of North and South America, Europe, Africa and Antarctica. It is also the youngest of the oceans and probably did not exist 100 million years ago. It covers about 20% of the Earth's surface, with an area of 82,362,000 sq km. It has an average depth of 3,926 m. The deepest spot is the Puerto Rico Trench which is 8,381 m. Other notable trenches in the Atlantic are the South Sandwich Trench (8,428 m) and the Romanche Trench (7,760 m). The farthest distance across the Atlantic occurs between the United States and North Africa at 4,830 km. The shortest distance is between Senegal and Brazil at 2,575 km. The S shape of the Atlantic ocean results in two distinct basins with their own circulation systems. In the Northern Atlantic currents flow in a clockwise direction, while in the Southern Atlantic currents flow in a counterclockwise direction. This is a result of the Coriolis force. The Atlantic is separated from the Arctic Ocean by a ridge that runs between Greenland and Scotland which is often called telegraph plateau because of the numerous cables laid along the ridge. It is separated from the Pacific Ocean by the Drake Passage which runs between South American and Antarctica. The boundary between the Atlantic and Indian Oceans is the 20? E meridian. The northern and southern basins are separated at roughly 8? N latitude. The Atlantic is also split down by the middle by the Mid-Atlantic Ridge. The Mid-Atlantic Ridge also contains a rift that is constantly widening and filling with molten lava which is pushing North and South America away from Europe and Africa. There are few islands in the Atlantic. Most are concentrated around the Caribbean. Most of the islands are structurally part of continents or exposed peaks of subterranean mountain ridges. The Atlantic ocean is the busiest shipping ocean. The Atlantic ocean is the major artery between the Western and Eastern hemisphers. Economic activities include fishing, dredging of aragonite sands in The Bahamas, and production of crude oil and natural gas in the Caribbean Sea, Gulf of Mexico, and North Sea.

Arctic Ocean
This, the smallest of the four oceans, lies almost entirely above the Arctic Circle (66.5� N). Nearly surrounded by land, its only outlets are the Bering Strait between Alaska and Russia, Davis Strait between Greenland and Canada, and Denmark Strait and the Norwegian Sea between Greenland and Europe. The Arctic Ocean has an area of 14,090,000 sq km and an average depth of 3,658 m off of the continental shelf. The lowest point is Fram Basin which is 4,665 m deep. The Artic Ocean has the widest continental shelf of all the oceans. The Arctic Ocean is divided into two basins, the Eurasian Basin, and the North American Basin, by the Lomonosov Ridge. There are also submarine ridges between the Arctic and Atlantic Oceans. This results in a large stagnant pool of cold water at the bottom of the Arctic Ocean, since land and submarine ridges block water from flowing out. The main current in the Arctic Ocean is the East Greenland current. This current is strong due to the number of rivers that flow into the Arctic Sea, the low rate of evaporation, and the land and submarine ridges surrounding the ocean. Two other weak currents flow out of the Arctic Ocean, the Labrador Current which runs through Smith Sound and Baffin Bay, and one that runs out of the Bering Straight. There is also a circular current in the Arctic Basin which is created by water deflecting off of Northern Greenland. The central part of the ocean is permanently covered in about ten feet of ice. Pressure ridges in the ice can sometimes reach three times that height. In the summer months, the icepack is surrounded by water and free-floating. During the winter, the icepack expands to nearly twice its summer area, reaching the land on all sides. Due to the extreme temperatures people thought that non-oceanic life didn't exist in the Arctic. However, marine life abounds in the open seas, and hares, polar bears, seals, gulls, and guillemots have been found as far north as 88�.

Indian Ocean

The Indian Ocean, not including the Antarctic region.


The Indian Ocean is the third largest of the world's oceanic divisions, covering about 20% of the water on the Earth's surface.[1] It is bounded on the north by the Indian subcontinent; on the west by East Africa; on the east by Indochina, the Sunda Islands, and Australia; and on the south by the Southern Ocean (or, depending on definition, by Antarctica). It is the only ocean to be named after the name of a country, i.e., India.[2][3][4] As one component of the interconnected global ocean, the Indian Ocean is delineated from the Atlantic Ocean by the 20° east meridian running south from Cape Agulhas, and from the Pacific by the meridian of 146°55' east[5]. The northernmost extent of the Indian Ocean is approximately 30° north in the Persian Gulf. The Indian Ocean has asymmetric ocean circulation[citation needed]. This ocean is nearly 10,000 kilometres (6,200 mi) wide at the southern tips of Africa and Australia; its area is 73,556,000 square kilometres (28,400,000 mi2), including the Red Sea and the Persian Gulf. The ocean's volume is estimated to be 292,131,000 cubic kilometres (70,086,000 mi3).[6] Small islands dot the continental rims. Island nations within the ocean are Madagascar, the world's fourth largest island; Reunion Island; Comoros; Seychelles; Maldives; Mauritius; and Sri Lanka. The archipelago of Indonesia borders the ocean on the east.

Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east. At 169.2 million square kilometres (65.3 million square miles) in area, this largest division of the World Ocean – and, in turn, the hydrosphere – covers about 46% of the Earth's water surface and about 30% of its total surface.[1] The equator subdivides it into the North Pacific Ocean and South Pacific Ocean, with two exceptions: the Galápagos and Gilbert Islands, while straddling the equator, are deemed wholly within the South Pacific.[2] The Mariana Trench in the western North Pacific is the deepest point in the Pacific and in the world, reaching a depth of 10,911 metres (35,797 ft).[3] The Pacific Ocean was sighted by Europeans early in the 16th century, first by the Spanish explorer Vasco Núñez de Balboa who crossed the Isthmus of Panama in 1513 and named it Mar del Sur (South Sea). Its current name is however derived from the Luso-Latin macaronic Tepre Pacificum, "peaceful sea", bestowed upon it by the Portuguese explorer Ferdinand Magellan[4].

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