Jump to content

High Plains (United States)

From Wikipedia, the free encyclopedia

This is an old revision of this page, as edited by Bender235 (talk | contribs) at 20:09, 1 May 2016 (→Geography and climate). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

This article is about the geographic region in the United States. For the region in Australia, see High Plains (Australia).

Template:Geobox

The Western High Plains ecology region is designated by 25 on the map.
Childress County, Texas, June 1938.

The High Plains are a subregion of the Great Plains mostly in the Western United States, but also partly in the Midwest states of Nebraska, Kansas, and South Dakota, generally encompassing the western part of the Great Plains before the region reaches the Rocky Mountains. The High Plains are located in southeastern Wyoming, southwestern South Dakota, western Nebraska, eastern Colorado, western Kansas, eastern New Mexico, western Oklahoma, and south of the Texas Panhandle.[1] The southern region of the Western High Plains ecology region contains the geological formation known as Llano Estacado which can be seen from a short distance or from miles away on satellite maps.[2] From east to west, the High Plains rise in elevation from around 1,160 feet (350 m) to over 7,800 feet (2,400 m).[3]

Name

The term "Great Plains", for the region west of about the 96th or 98th meridian and east of the Rocky Mountains, was not generally used before the early 20th century. Nevin Fenneman's 1916 study, Physiographic Subdivision of the United States,[4] brought the term Great Plains into more widespread usage. Prior to 1916, the region was almost invariably called the High Plains, in contrast to the lower Prairie Plains of the Midwestern states.[5] Today the term "High Plains" is usually used for a subregion instead of the whole of the Great Plains.'

Geography and climate

The High Plains has a "cold semi-arid" climate—Köppen BSk—receiving between 10–20 inches (250–510 mm) of precipitation annually.

Due to low moisture and high elevation, the High Plains commonly experiences wide ranges and extremes in temperature. The temperature range from day to night is usually 30 degrees Fahrenheit, and 24-hour temperature shifts of 100 degrees Fahrenheit are possible, as evidenced by a weather event that occurred in Browning, Montana from January 23, 1916 to January 24, 1916, when the temperature fell 100 °F (56 °C) from 44 °F (7 °C) to −56 °F (−49 °C). This is the United States and also the world record for the greatest temperature change in 24 hours.[6] The region is known for the steady, and sometimes intense, winds that prevail from the west. The winds add a considerable wind chill factor in the winter. The development of wind farms in the High Plains is one of the newest areas of economic development.

The High Plains are anomalously high in elevation. An explanation has recently been proposed to explain this high elevation. As the Farallon plate was subducted into the mantle beneath the region, water trapped in hydrous minerals in the descending slab was forced up into the lower crust above. Within the crust this water caused the hydration of dense garnet and other phases into lower density amphibole and mica minerals. The resulting increase in crustal volume raised the elevation nearly two kilometers.[7][8]

Flora

Plants endemic to the region are Shortgrass prairie, prickly pear cacti and scrub.

Economy

Agriculture in the forms of cattle ranching and the growing of wheat, corn and sunflowers is the primary economic activity in the region. The aridity of the region necessitates either dryland farming methods or irrigation; much water for irrigation is drawn from the underlying Ogallala Aquifer, which makes it possible to grow water-intensive crops such as corn, which the region's aridity would otherwise not support.[citation needed] Some areas of the High Plains have significant petroleum and natural gas deposits.

The combination of oil, natural gas, and wind energy along with plentiful underground water, has allowed some areas (such as West Texas) to sustain a range of economic activity, including occasional industry. For example, the ASARCO refinery in Amarillo, Texas has been in operation since 1924 due to the plentiful and inexpensive natural gas and water that are needed in metal ore refining.[citation needed]

Demographics

The High Plains has one of the lowest population densities of any region in the continental United States; Wyoming, for example, has the second lowest population density in the country after Alaska. In contrast to the rather low and stagnant population in the northern and western High Plains, cities in west Texas have shown sustained growth; Amarillo and Lubbock both have populations near or above 200,000 and continue to grow.[citation needed] Smaller towns, on the other hand, often struggle to sustain their population.

Major Cities and Towns

See also

Notes

  1. ^ File:Level III ecoregions, United States.png
  2. ^ "Shaded relief image of the Llano Estacado". Handbook of Texas: Llano Estacado.
  3. ^ Cite error: The named reference USGS was invoked but never defined (see the help page).
  4. ^ Fenneman, Nevin M. (January 1917). "Physiographic Subdivision of the United States". Proceedings of the National Academy of Sciences of the United States of America. 3 (1): 17–22. doi:10.1073/pnas.3.1.17. OCLC 43473694. PMC 1091163. PMID 16586678. {{cite journal}}: |access-date= requires |url= (help)
  5. ^ Brown, Ralph Hall (1948). Historical Geography of the United States. New York: Harcourt, Brace & Co. pp. 373–374. OCLC 186331193.
  6. ^ "Top Ten Montana Weather Events of the 20th Century". National Weather Service Unveils Montana's Top Ten Weather/Water/Climate Events of the 20th Century. National Weather Service. Retrieved 1 June 2015.
  7. ^ Why Are the High Plains So High? THECHERRYCREEKNEWS.COM, Mar 15, 2005 (2015?)
  8. ^ Jones, Craig H.; Mahan, Kevin H.; Butcher, Lesley A.; Levandowski, William B.; Farmer, G. Lang (2015). "Continental uplift through crustal hydration". Geology. 43 (4): 355–358. doi:10.1130/G36509.1.

Retrieved from "https://en.wikipedia.org/w/index.php?title=High_Plains_(United_States)&oldid=718145826"