Revision as of 23:44, 14 November 2019 editInternetArchiveBot (talk | contribs)Bots, Pending changes reviewers5,381,525 edits Rescuing 1 sources and tagging 0 as dead.) #IABot (v2.0← Previous edit | Revision as of 16:23, 18 November 2019 edit undo96.73.128.17 (talk) The summary of the definition of geography.Tag: blankingNext edit → | ||
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Geography is the study of earth and how it formed. | |||
==Geography== | |||
] of the ] of north central ], taken from the ] on October 28, 2008]] | |||
The Continental Divide begins at ], ], the westernmost point on the mainland of the Americas. The Divide crosses northern Alaska into the ], then zig-zags south into ] via the ] and ] and northern ] to ], north of the city of ] and just south of the community of ]. From there the Divide traverses the ] to the spine of the Rockies, following the crest of the ] southeast to the ], from there forming the boundary between southern British Columbia and southern ]. | |||
], here in mid-June 2007, at 14,278 ft it is the highest point of the Continental Divide in North America. ]] | |||
].]] | |||
The Divide crosses into the ] in northwestern ], at the boundary between ] and ]. In Canada, it forms the western boundary of Waterton Lakes National Park, and in the US bisects Glacier National Park. Further south, the Divide forms the backbone of the ] (Front Range) in the ], heads south towards ] and ], then west past the namesake community of ], through the Anaconda-Pintler Wilderness to the ], where it forms the eastern third of the state boundary between ] and Montana. The Divide crosses into ] within ] and continues southeast into ] where it reaches its highest point in North America at the summit of ] at {{convert|4352|m|abbr=in}}.{{citation needed|date=November 2015}} It crosses US Hwy 160 in southwestern Colorado at ], where a line symbolizes the division. The Divide then proceeds south into western ], passing along the western boundary of the endorheic Plains of San Agustin. Although the Divide represents the height of land between watersheds, it does not always follow the highest ranges/peaks within each state or province. | |||
In Mexico, it passes through ], ], ], ], ], ], ], ], the ], ], ], ], and ]. In Central America, it continues through southern ], southwestern ], western ], western/southwestern ], and southern ]. The divide reaches its lowest natural point in Central America at the ] at {{convert|47|m|abbr=in}} in Nicaragua. In Panama, the ] cuts through it at 85 ft (26 m). | |||
The Divide continues into ], where it follows the peaks of the ], traversing western ], central ], western and southwestern ], and eastern ] (essentially conforming to the Chile-] and Chile-] boundaries), southward to the southern end of ] and ]. | |||
In ], another, mainly non-mountainous divide, the ] (or Northern Divide), further separates the ]-] drainage region from the Atlantic watershed region. Secondary divides separate the watersheds that flow into the ] and ] (ultimately into the Atlantic) from watersheds that flow to the Atlantic via the ]. Another secondary divide follows the Appalachian chain, which separates those streams and rivers that flow directly into the Atlantic Ocean from those that exit via the Mississippi River. | |||
===Triple points=== | |||
] in ], Montana, is the point where two of the principal continental divides in North America converge, the primary Continental Divide and the Northern or Laurentian Divide. From this point, waters flow to the Pacific Ocean, the Atlantic Ocean via the Gulf of Mexico, and the ] via ]. Most geographers, geologists, meteorologists, and oceanographers consider this point the hydrological apex of North America, as Hudson Bay is generally considered part of the Arctic. For example, the ] (in its current unapproved working edition only<ref>{{cite web|url= https://www.iho.int/mtg_docs/com_wg/S-23WG/S-23WG_Misc/Draft_2002/Draft_2002.htm |title=IHO Publication S-23 Limits of Oceans and Seas; Chapter 9: Arctic Ocean|publisher=International Hydrographic Organization|date=2002|accessdate=2017-07-01}}</ref> of ''Limits of Oceans and Seas'') defines the Hudson Bay, with its outlet extending from 62.5 to 66.5 degrees north (just a few miles south of the ]) as being part of the Arctic Ocean, specifically "Arctic Ocean Subdivision 9.11." | |||
This hydrological apex of North America status of Triple Divide Peak is the main reason behind the designation of ] as the "Crown of the Continent" of North America.<ref>{{cite web|url=http://flbs.umt.edu/lake/stateofthelake.aspx |title=State of Flathead Lake |publisher=University of Montana Flathead Lake Biological Station |accessdate=2015-09-28}}</ref> The summit of the peak is the world's only oceanic triple divide point.<ref name=World>{{cite web|url=http://www.peakbagger.com/list.aspx?lid=1750 |title=Ocean Triple Divide Points |publisher=Peakbagger.com|accessdate=2017-07-01}}</ref> Discounting ] and its ice sheets, only one other continent (]) borders three oceans, but the inward-draining ] area of ] from western ] to the ] and ] Seas is so vast that any Arctic and ] tributaries are never within proximity of each other.<ref name=World></ref> Thus, North America's status of having a single location draining into three oceans is unique in the world. | |||
Sources differ, however, on whether Hudson Bay, entirely south of the ], is part of the Atlantic or Arctic Ocean.<ref>{{cite book |last= Sanford |first= Robert W. |title= Our World's Heritage: Creating a Culture Worthy of Place in Canada's Western Mountain Parks |year= 2010 |publisher= Athabasca University Press |isbn= 978-1-897425-57-2 |url= https://books.google.com/books?id=2aPnUlT5HAkC&pg=PA160 |page= 160}}</ref> Hudson Bay's water budget connects to the Atlantic more than to the Arctic Ocean.<ref name="LewisJones2000">{{cite book|editor-last1=Lewis|editor-first1=Edward Lyn |editor-last2=Jones|editor-first2=E. Peter |display-editors=etal |title=The Freshwater Budget of the Arctic Ocean |url=https://books.google.com/books?id=sZX_p5IKAxUC&pg=PA101 |accessdate=26 November 2010|year=2000|publisher=Springer|isbn=978-0-7923-6439-9|page=101}}</ref> The channels to the north of Hudson Bay are largely cut off by ] from the Arctic, so much of the water that enters it mixes with the Atlantic to the east via ] rather than north into the Arctic. The result is that most of the ice flowing down the ] eventually ends up as water in the Atlantic Ocean.<ref>{{cite web | |||
| last = Timmer | |||
| first = Henry | |||
| title = Snow Dome - The Hydrological Apex of North America | |||
| work = Snow Dome | |||
| publisher = climbwild.net | |||
| year = 2006 | |||
| url = http://climbwild.net/MP_Snow_Dome_page_one.html | |||
| accessdate = 2007-12-28 | |||
| archive-url = https://web.archive.org/web/20071025025035/http://climbwild.net/MP_Snow_Dome_page_one.html | |||
| archive-date = 2007-10-25 | |||
| url-status = dead | |||
}}</ref><ref>{{cite web | |||
| last = Timmer | |||
| first = Henry | |||
| title = The Columbia Icefield | |||
| publisher = climbwild.net | |||
| url = http://climbwild.net/MP_Columbia_Icefield_page_one.html | |||
| accessdate = 2014-07-30}}</ref> | |||
If Hudson Bay is considered part of the Atlantic, then the ''triple point'' is at an unimportant-looking, permanently snow and ice covered hump on the border between ] and ], on the southern slope of ] at {{convert|3456|m|ft|sigfig=3}}. The exact location of this potential triple point is somewhat indeterminate because the Columbia Icefield and the snow on top of it shifts from year to year. The snow that falls on it (about {{convert|10|m|ft}} per year) does not actually flow downhill as water, but creeps downhill in the form of glacial ice. | |||
That ice flows down the ] to the Arctic Ocean via the ] and ]s. Ice flowing west goes to the Pacific Ocean via Bryce Creek and the ] and ]s. Ice flowing down the Saskatchewan Glacier goes via the ], ], and ]s into ].<ref>{{cite web| url=http://www.peakbagger.com/peak.aspx?pid=24218 |title=Snow Dome-South Slope, British Columbia |work=Peakbagger |accessdate=2015-09-28}}</ref> | |||
While Triple Divide Peak (or, alternatively, Snow Dome) is the world's only oceanic triple divide, there are secondary triple divide points wherever any two continental divides meet. North America could be considered to have five major drainage systems: into the Pacific, Atlantic and Arctic Oceans, plus Hudson Bay and the Gulf of Mexico. Other sources such as the ] add a sixth: Canada's ] basin. Using just the five, there are four secondary continental divides and three secondary triple points, the two mentioned previously and a third near ], where the ] intersects the ] divide.<ref> | |||
{{cite book | |||
| last = monica driscollian rivers atlas | |||
| first = | |||
| chapter = Minnesota Rivers Map | |||
| title = Minnesota State Map Collection | |||
| publisher = Geology.com | |||
| year = 2006 | |||
| url = http://geology.com/state-map/minnesota.shtml | |||
| accessdate = 2007-12-29}}</ref> Since there is no true consensus on what a continental divide is, there is no real agreement on where the secondary triple points are located.<ref> | |||
{{cite web | |||
|last=Gonzalez | |||
|first=Mark A. | |||
|title=Continental Divides in North Dakota and North America | |||
|work=NGDS Newsletter | |||
|publisher=North Dakota Geological Survey | |||
|year=2002 | |||
|url=https://www.dmr.nd.gov/ndgs/Newsletter/NLS03/pdf/Divide.pdf | |||
|accessdate=2007-12-29 | |||
|url-status=dead | |||
|archiveurl=https://web.archive.org/web/20130117052801/https://www.dmr.nd.gov/ndgs/NEWSLETTER/NLS03/pdf/Divide.pdf | |||
|archivedate=2013-01-17 | |||
}}</ref> However, the main Continental Divide described in this article is a far more distinctive geological feature than the others and its two main triple points are much more prominent. | |||
===Hiking trail=== | |||
] | |||
The ] (CDT) follows the Divide through the U.S. from the ] to the ]. The trail itself is a corridor of pathways - i.e. dedicated footpaths or back roads, either on or near the Continental Divide. A less-developed Canadian extension called the ] continues through five ] and six ]s, ending at Kakwa Lake in east-central British Columbia.<ref>{{cite book | |||
| last = Lynx | |||
| first = Dustin | |||
| title = Hiking Canada's Great Divide Trail | |||
| publisher = Rocky Mountain Books | |||
| year = 2000 | |||
| url = http://rmbooks.com/book_details.php?isbn_upc=9781894765893 | |||
| isbn = 0-921102-79-8}}</ref>{{clear}} | |||
==Exceptions== | ==Exceptions== |
Revision as of 16:23, 18 November 2019
principal hydrological divide of North and South America "Continental Divide" redirects here. For other uses, see Continental divide (disambiguation).The Continental Divide of the Americas (also known as the Great Divide, the Western Divide or simply the Continental Divide; Template:Lang-es) is the principal, and largely mountainous, hydrological divide of the Americas. The Continental Divide extends from the Bering Strait to the Strait of Magellan, and separates the watersheds that drain into the Pacific Ocean from those river systems that drain into the Atlantic Ocean (including those that drain into the Gulf of Mexico and the Caribbean Sea) and, along the northernmost reaches of the Divide, those river systems that drain into the Arctic Ocean.
Although there are many other hydrological divides in the Americas, the Continental Divide is by far the most prominent of these because it tends to follow a line of high peaks along the main ranges of the Rocky Mountains and Andes, at a generally much higher elevation than the other hydrological divisions.
Geography is the study of earth and how it formed.
Exceptions
This section possibly contains unsourced predictions, speculative material, or accounts of events that might not occur. Information must be verifiable and based on reliable published sources. Please help improve it by removing unsourced speculative content. (February 2019) (Learn how and when to remove this message) |
Many endorheic regions in North and South America complicate the simple view of east or west, "ocean-bound" water flow. Several endorheic basins straddle or adjoin the Continental Divide, notably the Great Divide Basin in Wyoming, the Plains of San Agustin and the Animas Valley in New Mexico, the Guzmán Basin in New Mexico and Chihuahua, Mexico, and both the Bolsón de Mapimí and the Llanos el Salado in Mexico. Such basins can be, and routinely are, assigned to one side of the Divide or the other by their lowest perimeter pass; in other words, an assignment is made by determining how the drainage would occur if the basin were to be progressively filled with water until it overflowed. Large-scale maps, such as those on this page, often show double divide lines when endorheic basins are involved. However, the detailed USGS topographic maps of the United States generally show only the main Divide as determined by the overflow rule. Among other things, this eliminates the need to trace out the boundary for a basin that is very shallow and has a nebulous rim, such as the San Luis Closed Basin in Colorado and the sink of the lost streams of Idaho.
Another rare exception occurs when a stream near a divide splits and flows in both directions, or a lake straddling the divide overflows in both directions. Examples of these are, respectively, North Two Ocean Creek and Isa Lake, both located on the Continental Divide in Wyoming. The Panama Canal has this same feature, but is man-made. Both the Chagres and Gatun rivers flow into Gatun Lake, which empties to both oceans.
Several small lakes along the Divide in the Rocky Mountains between Alberta and British Columbia flow into both provinces and thus into both Atlantic and Pacific Oceans. An example is the "Committee's Punch Bowl", a small lake located in the Athabasca Pass.
The Alpine Club of Canada's Abbot Pass Hut sits directly astride the Divide in Abbot Pass on the boundary between Banff National Park and Yoho National Park, and thus rainwater falling on the eastern half of the roof flows via Lake Louise into Hudson Bay, while rain falling on the western half flows via Lake O'Hara into the Pacific Ocean.
See also
Continental divides
Other related
- Great Divide Trail
- Great Divide Mountain Bike Route
- Continental Divide Trail
- Laurentia
- List of railroad crossings of the North American continental divide
- Cromwell Dixon
- Lewis and Clark
Note
- It was named by Sir George Simpson, governor of the Hudson's Bay Company, while touring his vast Canadian fur-trading empire in 1825. According to historical sources, "The small circular basin of water at the summit, twenty yards in diameter, is dignified with the name of the 'Committee's Punch Bowl' in honour of which the Governor treated them (his fur traders) to a bottle of wine as they had 'neither time nor convenience to make a bowl of punch, although a glass of it would have been acceptable.'" The reference is to the governing committee of the Hudson's Bay Company in London, England.
References
- GeoBC (2013). "Committee Punch Bowl". gov.bc.ca. Province of British Columbia. Retrieved 2014-09-29.
External links
- A detailed map of watersheds in North America
- A detailed overview of isolated wetlands from the USFWS
- Detailed article, maps, and boundary data from The National Atlas of the United States
- Parting of the Waters: a creek that flows to two oceans
- U.S. Geological Survey Geographic Names Information System: Continental Divide (New Mexico, Colorado, Wyoming, Idaho, Montana)
- U.S. Geological Survey Geographic Names Information System: Continental Divide (Alaska)
Physical geography | ||
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