The Atlantic and Indian Oceans

The Atlantic Ocean lies in all hemispheres, stretching a long way from north to south between five continents. The textbook gives its area as 91 million km² (counted with its seas it is also given as about 106 million km²). Its name is linked to the Greek myth of Atlas, the hero who holds up the sky on his shoulders. The Age of Great Geographic Discoveries began from this ocean: Columbus, Dias, Cabot, da Gama, Magellan and others. The ocean arose from the splitting of Gondwana and Laurasia, which is why the coasts of South America and Africa fit each other. On its floor the Mid-Atlantic Ridge stretches about 15 000–16 000 km, with rifts along its middle; the deepest point is the Puerto Rico Trench (about 8 376 m; the textbook says 8 742 m). Surface water temperature is +27–28 °C at the equator and 0 to –1 °C near the poles. The ocean is quite salty, especially in the tropics and subtropics (up to 37 ‰ in subtropics; the Mediterranean 37–39 ‰). Currents form gyres; the warm Gulf Stream softens Europe’s climate. In the northern subtropics lies the Sargasso Sea — a sea without a coast, known for floating sargassum seaweed. The ocean ranks first in the world in sea transport; the Suez (1869) and Panama (1914) canals increased its importance; fishing is mostly in the north.