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Do not fill this in! == Geography == {{Further|Geography of North America|Geography of South America}} [[File:Earth-DSCOVR-20150706-IFV.jpg|thumb|Satellite photo of the Americas on [[Earth]]]] === Extent === The Americas make up most of the land in Earth's [[Western Hemisphere]].<ref> *{{citation|title=Merriam-Webster's Geographical Dictionary|year=2001|quote=The part of the Earth comprising North and South America and surrounding waters; longitudes 20°W and 160°E are often considered its boundaries|page=1294|contribution=Western Hemisphere|edition=3rd|place=Springfield, MA|publisher=Merriam-Webster}} *{{cite book|title=The Chambers Dictionary|date=2011|publisher=Chambers Harrap Publishers, Ltd.|isbn=978-0-550-10237-9|edition=12|location=London|page=1780|editor1-last=O'Neal|editor1-first=Mary}} *{{cite book|url=http://www.worldbook.com|title=The World Book Dictionary|date=2003|publisher=World Book, Inc|isbn=0-7166-0299-7|location=Chicago|page=2377|quote=Western Hemisphere, the half of the world that includes North and South America.}} *{{cite book|title=The American Heritage College Dictionary|date=2010|publisher=Houghton Mifflin Harcourt|isbn=978-0-618-83595-9|edition=Fourth|location=Boston|page=1557|quote=Western Hemisphere The half of the earth comprising North America, Central America, and South America}} *{{cite book|title=New Oxford American Dictionary|date=2010|publisher=Oxford University Press|edition=Third|location=New York|page=1963|quote=The Half of the earth that contains the Americas|editor1-last=Stevenson|editor1-first=Angus|editor2-last=Lindberg|editor2-first=Christine A.}} *{{cite book|title=Webster's New World College Dictionary|date=2014|publisher=Houghton Mifflin Harcourt|isbn=978-0-544-16606-6|edition=Fifth|location=Boston|quote=Western Hemisphere that half of the earth which includes North & South America}}</ref> The northernmost point of the Americas is [[Kaffeklubben Island]], which is the most northerly point of land on Earth.<ref>{{Cite news|last = Burress|first = Charles|url = http://sfgate.com/cgi-bin/article.cgi?file=/chronicle/archive/2004/06/17/BAG4J779M31.DTL&type=science|title = Romancing the north Berkeley explorer may have stepped on ancient Thule|work = San Francisco Chronicle|date = June 17, 2004|access-date = January 11, 2008|archive-date = May 9, 2012|archive-url = https://web.archive.org/web/20120509184952/http://www.sfgate.com/cgi-bin/article.cgi?file=%2Fchronicle%2Farchive%2F2004%2F06%2F17%2FBAG4J779M31.DTL&type=science|url-status = dead}}</ref> The southernmost point is the islands of [[Southern Thule]], although they are sometimes considered part of [[Antarctica]].<ref>{{cite web|url=http://www.coolantarctica.com/Travel/south_georgia_south_sandwich_islands.htm|title=South Georgia and the South Sandwich Islands, Antarctica – Travel|url-status=dead|archive-url=https://web.archive.org/web/20150219114729/http://www.coolantarctica.com/Travel/south_georgia_south_sandwich_islands.htm |archive-date=February 19, 2015}}</ref> The mainland of the Americas is the world's longest north-to-south landmass. The distance between its two polar extremities, [[Murchison Promontory]] on the [[Boothia Peninsula]] in northern Canada and [[Cape Froward]] in Chilean [[Patagonia]], is roughly {{cvt|14000|km|mi}}.<ref name="worldbook">{{cite encyclopedia|title = America|encyclopedia = The World Book Encyclopedia|volume = 1|pages = 407|publisher = World Book, Inc|year = 2006|isbn = 0-7166-0106-0}}</ref> The mainland's most westerly point is the end of the [[Seward Peninsula]] in Alaska; [[Attu Island]], further off the Alaskan coast to the west, is considered the westernmost point of the Americas. [[Ponta do Seixas]] in northeastern Brazil forms the easternmost extremity of the mainland,<ref name="worldbook" /> while [[Nordostrundingen]], in Greenland, is the most easterly point of the continental shelf. === Geology === South America broke off from the west of the supercontinent [[Gondwana]] around 135 million years ago, forming its own continent.<ref>{{Cite journal|last=Story|first=Brian C.|date=September 28, 1995|title=The role of mantle plumes in continental breakup: case histories from Gondwanaland|journal=Nature|volume=377|issue=6547|pages=301–309|doi=10.1038/377301a0|bibcode=1995Natur.377..301S|s2cid=4242617}}</ref> Around 15 million years ago, the collision of the [[Caribbean Plate]] and the [[Pacific Plate]] resulted in the emergence of a series of volcanoes along the border that created a number of islands. The gaps in the archipelago of Central America filled in with material eroded off North America and South America, plus new land created by continued volcanism. By three million years ago, the continents of North America and South America were linked by the [[Isthmus of Panama]], thereby forming the single landmass of the Americas.<ref>{{cite web|url=https://www.pbs.org/wnet/nature/andes/bridge.html |title=Land bridge: How did the formation of a sliver of land result in major changes in biodiversity |publisher=Public Broadcasting Corporation |url-status=dead |archive-url=https://web.archive.org/web/20071011111949/http://www.pbs.org/wnet/nature/andes/bridge.html |archive-date=October 11, 2007 }}</ref> The [[Great American Interchange]] resulted in many species being spread across the Americas, such as the [[cougar]], [[New World porcupine|porcupine]], [[opossum]]s, [[armadillo]]s and [[hummingbird]]s.<ref>{{cite news|url=http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=16401 |title=Panama: Isthmus that Changed the World |access-date=July 1, 2008 |publisher=[[NASA]] Earth Observatory |url-status=dead |archive-url=https://web.archive.org/web/20070802015424/http://earthobservatory.nasa.gov/Newsroom/NewImages/images.php3?img_id=16401 |archive-date=August 2, 2007 }}</ref> === Topography === [[File:Aconcagua_(aerial).jpg|thumb|[[Aconcagua]], in [[Argentina]], is the highest peak in the Americas.]] The geography of the western Americas is dominated by the [[American Cordillera]], with the [[Andes]] running along the west coast of South America<ref>{{cite web|url=http://www.blueplanetbiomes.org/andes.htm|title=Andes Mountain Range|access-date=September 8, 2014|archive-url=https://web.archive.org/web/20170429034553/http://www.blueplanetbiomes.org/andes.htm|archive-date=April 29, 2017|url-status=dead|df=mdy-all}}</ref> and the [[Rocky Mountains]] and other [[North American Cordillera]] ranges running along the western side of North America.<ref>{{cite web|url=http://biology.usgs.gov/s+t/SNT/noframe/wm146.htm |title=Rocky Mountains |url-status=dead |archive-url=https://web.archive.org/web/20070714142008/http://biology.usgs.gov/s%2Bt/SNT/noframe/wm146.htm |archive-date=July 14, 2007 }}</ref> The {{convert|2300|km|mi|adj=mid|-long|sp=us}} [[Appalachian Mountains]] run along the east coast of North America from [[Alabama]] to [[Newfoundland (island)|Newfoundland]].<ref>{{cite web|url=http://www.ohiohistorycentral.org/entry.php?rec=2067 |title=Appalachian Mountains |publisher=Ohio History Central |url-status=dead |archive-url=https://web.archive.org/web/20070501041411/http://www.ohiohistorycentral.org/entry.php?rec=2067 |archive-date=May 1, 2007 }}</ref> North of the Appalachians, the [[Arctic Cordillera]] runs along the eastern coast of Canada.<ref>{{cite web|url=http://www.evergreen.ca/nativeplants/learn-more/arctic-cordillera.php|title=Arctic Cordillera|work=evergreen.ca|access-date=May 17, 2007|archive-date=April 18, 2009|archive-url=https://web.archive.org/web/20090418173914/http://www.evergreen.ca/nativeplants/learn-more/arctic-cordillera.php|url-status=dead}}</ref> The largest mountain ranges are the [[Andes]] and [[Rocky Mountains]]. The [[Sierra Nevada]] and the [[Cascade Range]] reach similar altitudes as the [[Rocky Mountains]], but are significantly smaller. In North America, the greatest number of [[fourteener]]s are in the United States, and more specifically in the U.S. state of [[Colorado]]. The highest peaks of the Americas are located in the [[List of mountains in the Andes|Andes]], with [[Aconcagua]] of [[Argentina]] being the highest; in North America [[Denali]] (Mount McKinley) in the U.S. state of [[Alaska]] is the tallest. Between its coastal mountain ranges, North America has vast flat areas. The [[Interior Plains]] spread over much of the continent, with low relief.<ref>{{cite web|url=http://vulcan.wr.usgs.gov/LivingWith/VolcanicPast/Notes/interior_plains_region.html|title=Interior Plains Region|access-date=September 8, 2014|url-status=dead|archive-url=https://web.archive.org/web/20130809003610/http://vulcan.wr.usgs.gov/LivingWith/VolcanicPast/Notes/interior_plains_region.html|archive-date=August 9, 2013|df=mdy-all}}</ref> The [[Canadian Shield]] covers almost 5 million km<sup>2</sup> of North America and is generally quite flat.<ref>{{cite web|url=http://redpath-museum.mcgill.ca/Qbp/Natural%20History/nat_hist.html|title=Natural History of Quebec|access-date=September 8, 2014|archive-url=https://web.archive.org/web/20110706185133/http://redpath-museum.mcgill.ca/Qbp/Natural%20History/nat_hist.html|archive-date=July 6, 2011|url-status=dead|df=mdy-all}}</ref> Similarly, the north-east of South America is covered by the flat [[Amazon basin]].<ref>{{cite web|url=http://www.amazonconservation.org/home/strategy.html |title=Strategy |publisher=Amazon Conservation Association |url-status=dead |archive-url=https://web.archive.org/web/20070403082802/http://www.amazonconservation.org/home/strategy.html |archive-date=April 3, 2007 }} </ref> The [[Brazilian Highlands]] on the east coast are fairly smooth but show some variations in landform, while farther south the [[Gran Chaco]] and [[Pampas]] are broad [[lowland]]s.<ref>{{cite web|url=http://www2.jpl.nasa.gov/srtm/southAmerica.htm|title=South America images|access-date=September 8, 2014}}</ref> === Climate === [[File:Americas Köppen Map.png|upright=1.3|thumb|Climate zones of the Americas in the [[Köppen climate classification]] system]] The climate of the Americas varies significantly from region to region. [[Tropical rainforest climate]] occurs in the latitudes of the [[Amazon rainforest|Amazon]], American [[cloud forest]]s, southeastern Florida and [[Darién Gap]]. In the [[Rocky Mountains]] and [[Andes]], dry and continental climates are observed. Often the higher altitudes of these mountains are snow-capped. Southeastern North America is well known for its occurrence of [[tornadoes]] and [[hurricanes]], of which the vast majority of tornadoes occur in the United States' [[Tornado Alley]],<ref name="Science News 1">{{cite magazine|url=http://www.sciencenews.org/articles/20020511/bob9.asp|title=Tornado Alley, USA|last=Perkins|first=Sid|date=May 11, 2002|magazine=[[Science News]]|pages=296–298|archive-url=https://web.archive.org/web/20060825011156/http://www.sciencenews.org/articles/20020511/bob9.asp|archive-date=August 25, 2006|access-date=May 29, 2011}}</ref> as well as in the southerly [[Dixie Alley]] in the North American late-winter and early spring seasons. Often parts of the Caribbean are exposed to the violent effects of hurricanes. These weather systems are formed by the collision of dry, cool air from Canada and wet, warm air from the Atlantic. === Hydrology === With coastal mountains and interior plains, the Americas have several large [[river basin]]s that drain the continents. The largest river basin in North America is that of the [[Mississippi River|Mississippi]], covering the second largest [[Drainage basin|watershed]] on the planet.<ref>{{cite web|url=http://biology.usgs.gov/s+t/SNT/noframe/ms137.htm |title=Mississippi River |url-status=dead |archive-url=https://web.archive.org/web/20070715014306/http://biology.usgs.gov/s%2Bt/SNT/noframe/ms137.htm |archive-date=July 15, 2007 }}</ref> The Mississippi-Missouri river system drains most of 31 states of the U.S., most of the [[Great Plains]], and large areas between the Rocky and Appalachian mountains. This river is the [[List of rivers by length|fourth longest in the world]] and [[List of rivers by discharge|tenth most powerful in the world]]. In North America, to the east of the [[Appalachian Mountains]], there are no major rivers but rather a series of rivers and streams that flow east with their terminus in the Atlantic Ocean, such as the [[Hudson River]], [[Saint John River (Bay of Fundy)|Saint John River]], and [[Savannah River]]. A similar instance arises with central Canadian rivers that drain into [[Hudson Bay]]; the largest being the [[Churchill River (Hudson Bay)|Churchill River]]. On the west coast of North America, the main rivers are the [[Colorado River]], [[Columbia River]], [[Yukon River]], [[Fraser River]], and [[Sacramento River]]. The Colorado River drains much of the [[Southern Rockies]] and parts of the [[Basin and Range Province]]. The river flows approximately {{convert|1450|mi|km|sp=us}} into the [[Gulf of California]],<ref name=largest>{{cite web |last= Kammerer |first= J.C. |title= Largest Rivers in the United States |url= http://pubs.usgs.gov/of/1987/ofr87-242/ |publisher= United States Geological Survey |access-date=July 2, 2010}}</ref> during which over time it has carved out natural phenomena such as the [[Grand Canyon]] and created phenomena such as the [[Salton Sea]]. The Columbia is a large river, {{convert|1243|mi|km}} long, in central western North America and is the most powerful river on the West Coast of the Americas. In the far northwest of North America, the Yukon drains much of the Alaskan peninsula and flows {{convert|1980|mi|km}}<ref>{{cite web |url=http://www.yukoninfo.com/yukonriver/ |title=Yukoninfo.com |publisher=Yukoninfo.com |access-date=January 30, 2012 |archive-url=https://web.archive.org/web/20131024100547/http://www.yukoninfo.com/yukonriver/ |archive-date=October 24, 2013 |url-status=dead }}</ref> from parts of Yukon and the Northwest Territory to the Pacific. Draining to the Arctic Ocean of Canada, the [[Mackenzie River]] drains waters from the Arctic Great Lakes of Arctic Canada, as opposed to the Saint-Lawrence River that drains the Great Lakes of Southern Canada into the Atlantic Ocean. The Mackenzie River is the largest in Canada and drains {{convert|1805200|km2|mi2|sp=us}}.<ref>{{cite encyclopedia|url=https://www.britannica.com/eb/article-9110728 |title=Mackenzie River |encyclopedia=Encyclopædia Britannica |access-date=September 8, 2014 |url-status=dead |archive-url=https://web.archive.org/web/20081118141110/https://www.britannica.com/eb/article-9110728 |archive-date=November 18, 2008 }}</ref> The largest river basin in South America is that of the [[Amazon Basin|Amazon]], which has the highest volume flow of any river on Earth.<ref>{{cite web|url = http://www.greatestplaces.org/notes/amazon.htm|title = Greatest Places: Notes: Amazonia}}</ref> The second largest watershed of South America is that of the [[Paraná River]], which covers about 2.5 million km<sup>2</sup>.<ref>{{cite web|url=http://www.nature.org/wherewework/greatrivers/samerica/|title=Great Rivers Partnership – Paraguay-Parana|url-status=dead|archive-url=https://web.archive.org/web/20110105102114/http://www.nature.org/wherewework/greatrivers/samerica/ |archive-date=January 5, 2011}}</ref> === Ecology === North America and South America began to develop a shared population of flora and fauna around 2.5 million years ago, when [[continental drift]] brought the two continents into contact via the [[Isthmus of Panama]]. Initially, the exchange of biota was roughly equal, with North American genera migrating into South America in about the same proportions as South American genera migrated into North America. This exchange is known as the [[Great American Interchange]]. The exchange became lopsided after roughly a million years, with the total spread of South American genera into North America far more limited in scope than the spread of North American genera into South America.<ref>{{cite journal | title = Ecogeography and the Great American Interchange | last = Webb | first = S. David | journal = Paleobiology | volume = 17 | pages = 266–280 | number = 3 | year = 1991 | publisher = Paleontological Society | jstor=2400869| doi = 10.1017/S0094837300010605 | bibcode = 1991Pbio...17..266W | s2cid = 88305955 }}</ref> Summary: Please note that all contributions to Christianpedia may be edited, altered, or removed by other contributors. 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