XX

356,000 km

note: 95 nations and other entities are islands that border no other countries: American Samoa, Anguilla, Antigua and Barbuda, Aruba, Ashmore and Cartier Islands, The Bahamas, Bahrain, Baker Island, Barbados, Bermuda, Bouvet Island, British Indian Ocean Territory, British Virgin Islands, Cabo Verde, Cayman Islands, Christmas Island, Clipperton Island, Cocos (Keeling) Islands, Comoros, Cook Islands, Coral Sea Islands, Cuba, Curacao, Cyprus, Dominica, Falkland Islands (Islas Malvinas), Faroe Islands, Fiji, French Polynesia, French Southern and Antarctic Lands, Greenland, Grenada, Guam, Guernsey, Heard Island and McDonald Islands, Howland Island, Iceland, Isle of Man, Jamaica, Jan Mayen, Japan, Jarvis Island, Jersey, Johnston Atoll, Kingman Reef, Kiribati, Madagascar, Maldives, Malta, Marshall Islands, Mauritius, Mayotte, Federated States of Micronesia, Midway Islands, Montserrat, Nauru, Navassa Island, New Caledonia, New Zealand, Niue, Norfolk Island, Northern Mariana Islands, Palau, Palmyra Atoll, Paracel Islands, Philippines, Pitcairn Islands, Puerto Rico, Saint Barthelemy, Saint Helena, Saint Kitts and Nevis, Saint Lucia, Saint Pierre and Miquelon, Saint Vincent and the Grenadines, Samoa, Sao Tome and Principe, Seychelles, Singapore, Sint Maarten, Solomon Islands, South Georgia and the South Sandwich Islands, Spratly Islands, Sri Lanka, Svalbard, Taiwan, Tokelau, Tonga, Trinidad and Tobago, Turks and Caicos Islands, Tuvalu, Vanuatu, Virgin Islands, Wake Island, Wallis and Futuna

3,242,917 sq km (2012 est.)

aquifers are underground layers of water-bearing permeable rock formations; groundwater from aquifers can be extracted using a water well The World Factbook lists 37 major aquifers across 52 countries: Africa - 13 Asia - 10 North America - 5 South America - 3 Europe - 4 Australia -2 these aquifers contain the bulk of the stored volume of groundwater; this represents more than 30% of the world's fresh water; in the US, groundwater is primarily used for irrigation; globally, 70% of the groundwater withdrawn is used for agriculture; groundwater also supplies almost half of all drinking water worldwide

top fifteen World Factbook entities ranked by size: Pacific Ocean 155,557,000 sq km; Atlantic Ocean 76,762,000 sq km; Indian Ocean 68,556,000 sq km; Southern Ocean 20,327,000 sq km; Russia 17,098,242 sq km; Antarctica 14,200,000 sq km; Arctic Ocean 14,056,000 sq km; Canada 9,984,670 sq km; United States 9,826,675 sq km; China 9,596,960 sq km; Brazil 8,515,770 sq km; Australia 7,741,220 sq km; European Union 4,324,782 sq km; India 3,287,263 sq km; Argentina 2,780,400 sq km top ten largest water bodies: Pacific Ocean 155,557,000 sq km; Atlantic Ocean 76,762,000 sq km; Indian Ocean 68,556,000 sq km; Southern Ocean 20,327,000 sq km; Arctic Ocean 14,056,000 sq km; Coral Sea 4,184,100 sq km; South China Sea 3,595,900 sq km; Caribbean Sea 2,834,000 sq km; Bering Sea 2,520,000 sq km; Mediterranean Sea 2,469,000 sq km top ten largest landmasses: Asia 44,568,500 sq km; Africa 30,065,000 sq km; North America 24,473,000 sq km; South America 17,819,000 sq km; Antarctica 14,200,000 sq km; Europe 9,948,000 sq km; Australia 7,741,220 sq km; Greenland 2,166,086 sq km; New Guinea 785,753 sq km; Borneo 751,929 sq km top ten largest islands: Greenland 2,166,086 sq km; New Guinea (Indonesia, Papua New Guinea) 785,753 sq km; Borneo (Brunei, Indonesia, Malaysia) 751,929 sq km; Madagascar 587,713 sq km; Baffin Island (Canada) 507,451 sq km; Sumatra (Indonesia) 472,784 sq km; Honshu (Japan) 227,963 sq km; Victoria Island (Canada) 217,291 sq km; Great Britain (United Kingdom) 209,331 sq km; Ellesmere Island (Canada) 196,236 sq km top ten longest* mountain ranges (land-based): Andes (Venezuela, Colombia, Ecuador, Peru, Bolivia, Chile, Argentina) 7,000 km; Rocky Mountains (Canada, US) 4,830 km; Great Dividing Range (Australia) 3,700 km; Transantarctic Mountains (Antarctica) 3,500 km; Kunlun Mountains (China) 3,000 km; Ural Mountains (Russia, Kazakhstan) 2,640 km; Atlas Mountains (Morocco, Algeria, Tunisia) 2,500 km; Appalachian Mountains (Canada, US) 2,400 km; Himalayas (Pakistan, Afghanistan, India, China, Nepal, Bhutan) 2,300 km; Altai Mountains (Kazakhstan, Russia, Mongolia) 2,000 km *lengths are approximate; if oceans are included, the Mid-Ocean Ridge is by far the longest mountain range at 40,389 km top ten largest forested countries (sq km and percent of land): Russia 8,149,310 (49.8%); Brazil 4,935,380 (58.9%); Canada 3,470,690 (38.2%); United States 3,103,700 (33.9%); China 2,098,640 (22.3%); Democratic Republic of the Congo 1,522,670 (67.2%); Australia 1,250,590 (16.3%); Indonesia 903,250 (49.9%); Peru 738,054 (57.7%); India 708,600 (23.8%) (2016 est.) top ten most densely forested countries (percent of land): Suriname (98.3%), Federated States of Micronesia (91.9%), Gabon (90%), Seychelles (88.4%), Palau (87.6%), Guyana (83.9%), Laos (82.1%), Solomon Islands (77.9%), Papua New Guinea (74.1%), Finland (73.1%) (2016 est.) top ten largest (non-polar*) deserts: Sahara (Algeria, Chad, Egypt, Libya, Mali, Mauritania, Niger, Western Sahara, Sudan, Tunisia) 9,200,000 sq km; Arabian (Saudi Arabia, Iraq, Jordan, Kuwait, Oman, Qatar, United Arab Emirates, Yemen) 2,330,000 sq km; Gobi (China, Mongolia) 1,295,000 sq km; Kalahari (Botswana, Namibia, South Africa) 900,000 sq km; Patagonian (Argentina) 673,000 sq km; Syrian (Syria, Iraq, Jordan, Saudi Arabia) 500,000 sq km; Chihuahuan (Mexico) 362,000 sq km; Kara-Kum (Turkmenistan) 350,000 sq km; Great Victoria (Australia) 348,750 sq km; Great Basin (United States) 343,169 sq km *if the two polar deserts were included, they would rank first and second: Antarctic Desert 14,200,000 sq km and Arctic Desert 13,900,000 sq km ten smallest independent countries: Holy See (Vatican City) 0.44 sq km; Monaco 2 sq km; Nauru 21 sq km; Tuvalu 26 sq km; San Marino 61 sq km; Liechtenstein 160 sq km; Marshall Islands 181 sq km; Cook Islands 236 sq km; Niue 260 sq km; Saint Kitts and Nevis 261 sq km

the land boundaries in The World Factbook total 279,035.5 km (not counting shared boundaries twice), but the number is only an estimate because of the difficulty in precisely measuring natural features such as rivers note 1: 46 nations and other areas are landlocked, these include: Afghanistan, Andorra, Armenia, Austria, Azerbaijan, Belarus, Bhutan, Bolivia, Botswana, Burkina Faso, Burundi, Central African Republic, Chad, Czechia, Eswatini, Ethiopia, Holy See (Vatican City), Hungary, Kazakhstan, Kosovo, Kyrgyzstan, Laos, Lesotho, Liechtenstein, Luxembourg, North Macedonia, Malawi, Mali, Moldova, Mongolia, Nepal, Niger, Paraguay, Rwanda, San Marino, Serbia, Slovakia, South Sudan, Switzerland, Tajikistan, Turkmenistan, Uganda, Uzbekistan, West Bank, Zambia, Zimbabwe; two of these, Liechtenstein and Uzbekistan, are doubly landlocked note 2: worldwide, about one quarter of interior (non-coastal) borders are rivers; South America with 43% leads the continents, followed by North America with 32%, Africa with 30%, Europe with 23%, and Asia with 18%; Australia has no interior national river borders note 3: two nations, China and Russia, each border 14 other countries

most countries make the following claims measured from the mean low-tide baseline as described in the 1982 UN Convention on the Law of the Sea: territorial sea - 12 nm, contiguous zone - 24 nm, and exclusive economic zone - 200 nm; additional zones provide for exploitation of continental shelf resources and an exclusive fishing zone; boundary situations with neighboring states prevent many countries from extending their fishing or economic zones to a full 200 nm

large areas of the world are subject to severe weather and natural disasters (cyclones, earthquakes, landslides, tsunamis, volcanic eruptions, etc.) volcanism: this is a driver and consequence of plate tectonics, the physical process reshaping the Earth's lithosphere; the world is home to more than 1,500 potentially active volcanoes, with over 500 of these erupting in recorded history; an estimated 500 million people live near volcanoes; associated dangers include lava flows, mud flows, pyroclastic flows, ash clouds, ash fall, ballistic projectiles, gas emissions, landslides, earthquakes, and tsunamis; in the 1990s, the International Association of Volcanology and Chemistry of the Earth's Interior created a list of 16 "Decade Volcanoes" with great potential for destruction: Avachinsky-Koryaksky (Russia), Colima (Mexico), Etna (Italy), Galeras (Colombia), Mauna Loa (US), Merapi (Indonesia), Nyiragongo (Democratic Republic of the Congo), Rainier (US), Sakurajima (Japan), Santa Maria (Guatemala), Santorini (Greece), Taal (Philippines), Teide (Spain), Ulawun (Papua New Guinea), Unzen (Japan), Vesuvius (Italy) volcano statistics: countries with the most volcanoes: (Holocene Epoch, the past 12,000 years*): United States (162), Japan (122), Indonesia (120), Russia (117), Chile (91); *roughly 1,350 volcanoes have erupted over this time period; about 40-50 eruptions are ongoing at any one time; the frequency of volcanoes has not increased longest erupting volcano: Santa Maria volcano in Guatemala has been constantly erupting since 22 June 1922; the Yasur volcano on Tanna Island in Vanuatu has been in constant activity since Captain Cook observed it in 1774, but it is not cited due to lack of a clear start date; tephra stratigraphy and radiocarbon dating show that the Yasur activity may have begun ca. A.D. 1270 highest volcano (above sea level): Nevado Ojos del Salado (6,893 m; 22,615 ft) on the Chile-Argentina border is the world's highest volcano above sea level and the highest peak in Chile highest volcano (from base): Mauna Kea (US) is the world's tallest mountain, measured from base to summit; the peak lies on the island of Hawaii, but its base begins more than 70 km (43 mi) offshore and at a depth of about 6,000 m; total height estimates range from 9,966 m to 10,203 m earthquakes: the vast majority of earthquakes occur in three large zones; the Circum-Pacific Belt (known as the Ring of Fire) borders the Pacific and is the largest zone of volcanic and seismic activity, with about 90% of earthquakes (81% of the largest) and about 75% of active volcanoes; the belt extends northward from Chile along the South American coast, then through Central America, Mexico, the western US, southern Alaska, and the Aleutian Islands, to Japan, the Philippines, Papua New Guinea, the southwestern Pacific, and New Zealand; the Alpide Belt extends from Java to Sumatra, northward along the mountains of Burma, eastward through the Himalayas and the Mediterranean, and into the Atlantic Ocean, accounting for about 17% of the largest earthquakes; the third belt follows the long Mid-Atlantic Ridge

note: the Earth is now thought to be about 4.55 billion years old, about one-third of the 13.8-billion-year age estimated for the universe; the earliest widely accepted date for life appearing on Earth is 3.48 billion years ago

land area about 16 times the size of the US

The surface of the Earth is approximately 70.9% water and 29.1% land. The water portion is the World Ocean, the single largest feature of the planet and one that connects all places on the globe. The continental landmasses divide this ocean into five major ocean basins, which are (in decreasing order of size) the Pacific, Atlantic, Indian, Southern, and Arctic. The World Factbook describes these five as oceans. Because of the major ocean currents and the effects of the major air masses above them, the Pacific and Atlantic Oceans are generally divided at the equator into the North and South Pacific Oceans and the North and South Atlantic Oceans, creating seven major water bodies -- the so-called "Seven Seas." About 97.5% of the Earth's water is saltwater. Of the 2.5% that is fresh, about two thirds is frozen, mostly locked up in mountain glaciers and the Antarctic ice sheets. If all the surface ice on earth fully melted, the sea level would rise about 70 m (230 ft). Earth's land portion is divided into landmasses called continents. Different continental definitions are recognized in certain parts of the world, with some more heavily based on culture than physical geography. Depending on the convention used, the number of continents can vary from five to seven. The most common classification recognizes seven, which are (from largest to smallest) Asia, Africa, North America, South America, Antarctica, Europe, and Australia. Asia and Europe are sometimes lumped together into a Eurasian continent, and North and South America are sometimes grouped as the Americas, with either usage resulting in a continent total of six (or five, if both are used). North America is commonly understood to include Greenland and the Caribbean islands and to extend south to the Isthmus of Panama. The Ural Mountains and the Ural River are usually considered the easternmost part of Europe, the Caspian Sea is the limit to the southeast, and the Caucasus Mountains, the Black Sea, and the Mediterranean to the south. Asia usually incorporates all the islands of the Philippines, Malaysia, and Indonesia. The Pacific islands are often lumped with Australia and designated as Oceania or Australasia. Africa's northeast extremity is frequently delimited at the Isthmus of Suez, but for geopolitical purposes, the Egyptian Sinai Peninsula is often included as part of Africa. In total, the United States recognizes 197 countries. Using the seven-continent model and grouping islands with adjacent continents, Africa has the most countries with 54. Europe has 49 countries and Asia 48, with five countries shared: Azerbaijan, Georgia, Kazakhstan, Russia, and Turkey. North America has 23, Oceania has 16, and South America has 12. countries by continent: Africa (54): Algeria, Angola, Benin, Botswana, Burkina Faso, Burundi, Cabo Verde, Cameroon, Central African Republic, Chad, Comoros, Democratic Republic of the Congo, Republic of the Congo, Cote d'Ivoire, Djibouti, Egypt, Equatorial Guinea, Eritrea, Eswatini, Ethiopia, Gabon, The Gambia, Ghana, Guinea, Guinea-Bissau, Kenya, Lesotho, Liberia, Libya, Madagascar, Malawi, Mali, Mauritania, Mauritius, Morocco, Mozambique, Namibia, Niger, Nigeria, Rwanda, Sao Tome and Principe, Senegal, Seychelles, Sierra Leone, Somalia, South Africa, South Sudan, Sudan, Tanzania, Togo, Tunisia, Uganda, Zambia, Zimbabwe Europe (49): Albania, Andorra, Austria, Azerbaijan*, Belarus, Belgium, Bosnia and Herzegovina, Bulgaria, Croatia, Czech Republic, Denmark, Estonia, Finland, France, Georgia*, Germany, Greece, Holy See (Vatican City), Hungary, Iceland, Ireland, Italy, Kazakhstan*, Kosovo, Latvia, Liechtenstein, Lithuania, Luxembourg, Malta, Moldova, Monaco, Montenegro, Netherlands, North Macedonia, Norway, Poland, Portugal, Romania, Russia*, San Marino, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey*, Ukraine, United Kingdom (* indicates part of the country is also in Asia) Asia (48): Afghanistan, Armenia, Azerbaijan*, Bahrain, Bangladesh, Bhutan, Brunei, Burma, Cambodia, China, Cyprus, Georgia*, India, Indonesia, Iran, Iraq, Israel, Japan, Jordan, Kazakhstan*, North Korea, South Korea, Kuwait, Kyrgyzstan, Laos, Lebanon, Malaysia, Maldives, Mongolia, Nepal, Oman, Pakistan, Philippines, Qatar, Russia*, Saudi Arabia, Singapore, Sri Lanka, Syria, Tajikistan, Thailand, Timor-Leste, Turkey*, Turkmenistan, United Arab Emirates, Uzbekistan, Vietnam, Yemen (* indicates part of the country is also in Europe) North America (23): Antigua and Barbuda, The Bahamas, Barbados, Belize, Canada, Costa Rica, Cuba, Dominica, Dominican Republic, El Salvador, Grenada, Guatemala, Haiti, Honduras, Jamaica, Mexico, Nicaragua, Panama, Saint Kitts and Nevis, Saint Lucia, Saint Vincent and the Grenadines, Trinidad and Tobago, United States Oceania (16): Australia, Cook Islands, Fiji, Kiribati, Marshall Islands, Federated States of Micronesia, Nauru, New Zealand, Niue, Palau, Papua New Guinea, Samoa, Solomon Islands, Tonga, Tuvalu, Vanuatu South America (12): Argentina, Bolivia, Brazil, Chile, Colombia, Ecuador, Guyana, Paraguay, Peru, Suriname, Uruguay, Venezuela Three of the states described above – France, Netherlands, and the United Kingdom – consist of smaller political entities that are referred to as countries. France considers French Polynesia an overseas country; the Kingdom of the Netherlands refers to all four of its constituent parts (the Netherlands and the islands of Aruba, Curacao, and Sint Maarten) as countries; and the United Kingdom is composed of the countries of England, Wales, Scotland, and Northern Ireland. the World from space: Earth is the only planet in the solar system to have water in its three states of matter: liquid (oceans, lakes, and rivers), solid (ice), and gas (water vapor in clouds). From a distance, Earth would be the brightest of the eight planets in the solar system because of the planet's water reflecting sunlight. Earth has a slight equatorial bulge -- a difference between its equatorial and polar diameters -- because of the centrifugal force from the planet rotating on its axis. The equatorial diameter is 12,756 km, but the polar diameter is 12,714 km; the circumference at the equator is 40,075 km, and the polar circumference is 40,008 km.

six of the world's seven continents are widely and permanently inhabited; Asia is the most populous continent, with about 60% of the world's population (China and India together account for over 35%); Africa comes in second with over 15%, Europe has about 10%, North America 8%, South America almost 6%, and Oceania less than 1%; the harsh conditions on Antarctica prevent any permanent habitation

top ten largest natural lakes: Caspian Sea (Azerbaijan, Iran, Kazakhstan, Russia, Turkmenistan) 374,000 sq km; Lake Superior (Canada, United States) 82,100 sq km; Lake Victoria (Kenya, Tanzania, Uganda) 62,940 sq km; Lake Huron (Canada, United States) 59,600 sq km; Lake Michigan (United States) 57,750 sq km; Lake Tanganyika (Burundi, Democratic Republic of the Congo, Tanzania, Zambia) 32,000 sq km; Great Bear Lake (Canada) 31,328 sq km; Lake Baikal (Russia) 31,500 sq km; Lake Malawi (Malawi, Mozambique, Tanzania) 22,490 sq km; Great Slave Lake (Canada) 28,568 sq km note 1: the areas of the lakes are subject to seasonal variation; only the Caspian Sea is saline, the rest are fresh water note 2: Lakes Huron and Michigan are technically a single lake because the flow of water between the Straits of Mackinac that connects the two lakes keeps their water levels at near-equilibrium; combined, Lake Huron-Michigan is the largest freshwater lake by surface area in the world note 3: if ranked by water volume, the Caspian Sea would still be first, but it would be followed Lakes Baikal, Tanganyika, Superior, and Malawi; Lake Superior contains more water than the other four North American Great Lakes (Erie, Huron, Michigan, Ontario) combined

a watershed is a drainage basin on an area of land where precipitation collects and drains off into a common outlet, such as into a river, bay, or other body of water; oceans ultimately take in the drainage from 83% of all land area; the remaining 17% of the land drains into internal (endorheic) basins The World Factbook lists 51 watersheds across 102 countries: Asia - 18 Europe - 9 Africa - 9 North and Central America - 8 South America - 5 Australia - 2 all watersheds with an area of at least 500,000 sq km have been included, along with a number of smaller, regionally significant watersheds; together, these represent the surface hydrology water flows that are the world's primary sources of fresh water for individual consumption, industry, and agriculture

top ten longest rivers: Nile (Africa) 6,650 km; Amazon (South America) 6,436 km; Yangtze (Asia) 6,300 km; Mississippi-Missouri (North America) 6,275 km; Yenisey-Angara (Asia) 5,539 km; Huang He/Yellow (Asia) 5,464 km; Ob-Irtysh (Asia) 5,410 km; Congo (Africa) 4,700 km; Amur (Asia) 4,444 km; Lena (Asia) 4,400 km note: there are 21 countries without rivers: three in Africa (Comoros, Djibouti, Libya), one in the Americas (Bahamas), eight in Asia (Bahrain, Kuwait, Maldives, Oman, Qatar, Saudi Arabia, United Arab Emirates, Yemen), three in Europe (Malta, Monaco, Holy See), and six in Oceania (Kiribati, Marshall Islands, Nauru, Niue, Tonga, Tuvalu); these countries also do not have natural lakes