The Atlantic Ocean spans approximately 41,500,000 square miles and is the second largest ocean in the world. It covers roughly 20 percent of the Earth’s surface and is slightly more than half as large as the Pacific Ocean.
The Atlantic Ocean occupies an elongated S-shaped basin that borders Europe and Africa to the east and North and South America to the west. The ocean has an average depth of 10,955 feet and reaches its greatest depth of 27,490 feet in the Puerto Rico Trench. Its width varies from 1,770 miles between Brazil and Sierra Leone to approximately 4,000 miles in its southern portion. A recent discovery of a subduction zone caused by shifting tectonic plates off the Iberian Peninsula suggests that the Atlantic Ocean may be shrinking at a rate that would allow the European and North American continents to meet in about 220 million years.