Antarctica Europe Pacific Ocean Indian Ocean Atlantic Ocean Arctic Ocean

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<ul><li><p>7/29/2019 Antarctica Europe Pacific Ocean Indian Ocean Atlantic Ocean Arctic Ocean</p><p> 1/4</p><p>Antarctica</p><p>Antarctica is Earth's southernmost continent, underlying the South Pole. It is situated</p><p>in the Antarctic region of the southern hemisphere, almost entirely south of the</p><p>Antarctic Circle, and is surrounded by the Southern Ocean. At 14.0 million km2 (5.4</p><p>million sq mi), it is the fifth-largest continent in area after Asia, Africa, North</p><p>America, and South America. About 98% of Antarctica is covered by ice, which</p><p>averages at least 1.6 kilometres (1.0 mi) in thickness.</p><p>Antarctica, on average, is the coldest, driest, and windiest continent, and has the</p><p>highest average elevation of all the continents.[2] Antarctica is considered a desert,</p><p>with annual precipitation of only 200 mm (8 inches) along the coast and far less</p><p>inland.[3] There are no permanent human residents, but anywhere from 1,000 to 5,000</p><p>people reside throughout the year at the research stations scattered across the</p><p>continent. Only cold-adapted plants and animals survive there, including penguins,</p><p>seals, nematodes, tardigrades, mites, many types of algae and other microorganisms,</p><p>and tundra vegetation.</p><p>Although myths and speculation about a Terra Australis ("Southern Land") date back</p><p>to antiquity, the first confirmed sighting of the continent is commonly accepted to</p><p>have occurred in 1820 by the Russian expedition of Fabian Gottlieb von</p><p>Bellingshausen and Mikhail Lazarev. The continent, however, remained largely</p><p>neglected for the rest of the 19th century because of its hostile environment, lack of</p><p>resources, and isolation. The first formal use of the name "Antarctica" as a continental</p><p>name in the 1890s is attributed to the Scottish cartographer John George</p><p>Bartholomew. The name Antarctica means opposite to the north".[5]</p><p>The Antarctic Treaty was signed in 1959 by twelve countries; to date, forty-six</p><p>countries have signed the treaty. The treaty prohibits military activities and mineral</p><p>mining, supports scientific research, and protects the continent's ecozone. Ongoingexperiments are conducted by more than 4,000 scientists of many nationalities and</p><p>with various research interests.[1]</p><p>Europe</p><p>Europe is one of the world's seven continents. Comprising the westernmost peninsula</p><p>of Eurasia, Europe is generally divided from Asia to its east by the water divide of the</p><p>Ural Mountains, the Ural River, the Caspian Sea, the Caucasus region (Specification</p><p>of borders) and the Black Sea to the southeast.[2] Europe is bordered by the Arctic</p><p>Ocean and other bodies of water to the north, the Atlantic Ocean to the west, the</p></li><li><p>7/29/2019 Antarctica Europe Pacific Ocean Indian Ocean Atlantic Ocean Arctic Ocean</p><p> 2/4</p><p>Mediterranean Sea to the south, and the Black Sea and connected waterways to the</p><p>southeast. Yet the borders for Europea concept dating back to classical antiquity</p><p>are somewhat arbitrary, as the term continent can refer to a cultural and political</p><p>distinction or a physiographic one.</p><p>Europe is the world's second-smallest continent by surface area, covering about</p><p>10,180,000 square kilometres (3,930,000 sq mi) or 2% of the Earth's surface and</p><p>about 6.8% of its land area. Of Europe's approximately 50 states, Russia is the largest</p><p>by both area and population (although the country covers both Europe and Asia),</p><p>while the Vatican City is the smallest. Europe is the third-most populous continent</p><p>after Asia and Africa, with a population of 731 million or about 11% of the world's</p><p>population.</p><p>Europe, in particular Ancient Greece, is the birthplace of Western culture.[3] It played</p><p>a predominant role in global affairs from the 16th century onwards, especially after</p><p>the beginning of colonialism. Between the 16th and 20th centuries, European nations</p><p>controlled at various times the Americas, most of Africa, Oceania, and large portions</p><p>of Asia. Both World Wars were largely focused upon Europe, greatly contributing to</p><p>a decline in Western European dominance in world affairs by the mid-20th century as</p><p>the United States and Soviet Union took prominence.[4] During the Cold War, Europe</p><p>was divided along the Iron Curtain between NATO in the west and the Warsaw Pact</p><p>in the east. European integration led to the formation of the Council of Europe and the</p><p>European Union in Western Europe, both of which have been expanding eastward</p><p>since the fall of the Soviet Union in 1991.</p><p>Pacific Ocean</p><p>The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the</p><p>Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australiain the west, and the Americas in the east.</p><p>At 169.2 million square kilometres (63.8 million square miles) in area, this largest</p><p>division of the World Ocean and, in turn, the hydrosphere covers about 46% of the</p><p>Earth's water surface and about 30% of its total surface.[1] The equator subdivides it</p><p>into the North Pacific Ocean and South Pacific Ocean, with two exceptions: the</p><p>Galpagos and Gilbert Islands, while straddling the equator, are deemed wholly</p><p>within the South Pacific.[2] The Mariana Trench in the western North Pacific is the</p><p>deepest point in the Pacific and in the world, reaching a depth of 10,911 metres</p><p>(35,797 ft).[3]</p></li><li><p>7/29/2019 Antarctica Europe Pacific Ocean Indian Ocean Atlantic Ocean Arctic Ocean</p><p> 3/4</p><p>The Pacific Ocean was sighted by Europeans early in the 16th century, first by the</p><p>Spanish explorer Vasco Nez de Balboa who crossed the Isthmus of Panama in 1513</p><p>and named it Mar del Sur (South Sea). Its current name was given by Portuguese</p><p>explorer Ferdinand Magellan during the Spanish expedition of world</p><p>circumnavigation in 1521, who encountered calm seas during the journey and called it</p><p>Tepre Pacificum in Latin, meaning "pacific" or "peaceful sea".[4]</p><p>Indian Ocean</p><p>The Indian Ocean is the third largest of the world's oceanic divisions, covering about</p><p>20% of the water on the Earth's surface.[1] It is bounded on the north by the Indian</p><p>subcontinent; on the west by East Africa; on the east by Indochina, the Sunda Islands,</p><p>and Australia; and on the south by the Southern Ocean (or, depending on definition,</p><p>by Antarctica). It is the only ocean to be named after a country, i.e., India.[2][3][4]</p><p>As one component of the interconnected global ocean, the Indian Ocean is delineated</p><p>from the Atlantic Ocean by the 20 east meridian running south from Cape Agulhas,</p><p>and from the Pacific by the meridian of 14655' east[5]. The northernmost extent of</p><p>the Indian Ocean is approximately 30 north in the Persian Gulf. The Indian Ocean</p><p>has asymmetric ocean circulation[citation needed]. This ocean is nearly 10,000</p><p>kilometres (6,200 mi) wide at the southern tips of Africa and Australia; its area is</p><p>73,556,000 square kilometres (28,400,000 mi2), including the Red Sea and the</p><p>Persian Gulf.</p><p>The ocean's volume is estimated to be 292,131,000 cubic kilometres (70,086,000</p><p>mi3).[6] Small islands dot the continental rims. Island nations within the ocean are</p><p>Madagascar, the world's fourth largest island; Reunion Island; Comoros; Seychelles;</p><p>Maldives; Mauritius; and Sri Lanka. The archipelago of Indonesia borders the ocean</p><p>on the east.</p><p>Atlantic Ocean</p><p>The Atlantic Ocean is the second-largest of the world's oceanic divisions. With a total</p><p>area of about 106,400,000 square kilometres (41,100,000 sq mi), it covers</p><p>approximately twenty percent of the Earth's surface and about twenty-six percent of</p><p>its water surface area. The first part of its name refers to Atlas of Greek mythology,</p><p>making the Atlantic the "Sea of Atlas".</p><p>The oldest known mention of "Atlantic" is in The Histories of Herodotus around 450</p><p>BC (Hdt. 1.202.4): Atlantis thalassa (Greek: ; English: Sea of</p></li><li><p>7/29/2019 Antarctica Europe Pacific Ocean Indian Ocean Atlantic Ocean Arctic Ocean</p><p> 4/4</p><p>Atlas); see also: Atlas Mountains. Another name historically used was the ancient</p><p>term Ethiopic Ocean, derived from Ethiopia, whose name was sometimes used as a</p><p>synonym for all of Africa and thus for the ocean. Before Europeans discovered other</p><p>oceans, the term "ocean" itself was synonymous with the waters beyond the Strait of</p><p>Gibraltar that we now know as the Atlantic. The Greeks believed this ocean to be a</p><p>gigantic river encircling the world.</p><p>The Atlantic Ocean occupies an elongated, S-shaped basin extending longitudinally</p><p>between the Americas to the west, and Eurasia and Africa to the east. As one</p><p>component of the interconnected global ocean, it is connected in the north to the</p><p>Arctic Ocean (which is sometimes considered a sea of the Atlantic), to the Pacific</p><p>Ocean in the southwest, the Indian Ocean in the southeast, and the Southern Ocean in</p><p>the south. (Other definitions describe the Atlantic as extending southward to</p><p>Antarctica.) The equator subdivides it into the North Atlantic Ocean and South</p><p>Atlantic Ocean.</p><p>Arctic Ocean</p><p>The Arctic Ocean, located in the Northern Hemisphere and mostly in the Arctic north</p><p>polar region, is the smallest, and shallowest of the world's five major oceanic</p><p>divisions.[1] The International Hydrographic Organization (IHO) recognizes it as an</p><p>ocean, although some oceanographers call it the Arctic Mediterranean Sea or simply</p><p>the Arctic Sea, classifying it as one of the mediterranean seas of the Atlantic Ocean.</p><p>[2] Alternatively, the Arctic Ocean can be seen as the northernmost lobe of the all-</p><p>encompassing World Ocean.</p><p>Almost completely surrounded by Eurasia and North America, the Arctic Ocean is</p><p>partly covered by sea ice throughout the year[3] (and almost completely in winter).</p><p>The Arctic Ocean's temperature and salinity vary seasonally as the ice cover melts andfreezes;[4] its salinity is the lowest on average of the five major oceans, due to low</p><p>evaporation, heavy freshwater inflow from rivers and streams, and limited connection</p><p>and outflow to surrounding oceanic waters with higher salinities. The summer</p><p>shrinking of the ice has been quoted at 50%.[1] The National Snow and Ice Data</p><p>Center (NSIDC) uses satellite data to provide a daily record of Arctic sea ice cover</p><p>and the rate of melting compared to an average period and specific past years.</p></li></ul>

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