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25-663: The Colorado Piedmont elevation is lower than the foothills, but is also slightly lower elevation than the High Plains to the east. According to current geologic theory, the Piedmont was formed approximately 28 million years ago, during the broad bowing of the North American Plate that lifted the continent between present-day Kansas and Utah to its present elevation of approximately 5000 ft (1500 m). This uplift resulted in increased streamflow and rapid erosion on

50-462: A tropical savanna climate or a humid subtropical climate . These climates tend to have hot, or sometimes extremely hot, summers and warm to cool winters, with some to minimal precipitation. Hot semi-arid climates are most commonly found around the fringes of subtropical deserts. Hot semi-arid climates are most commonly found in Africa , Australia , and South Asia . In Australia, a large portion of

75-434: A location has a semi-arid climate, the precipitation threshold must first be determined. The method used to find the precipitation threshold (in millimeters): If the area's annual precipitation in millimeters is less than the threshold but more than half or 50% the threshold, it is classified as a BS (steppe, semi-desert, or semi-arid climate). Furthermore, to delineate hot semi-arid climates from cold semi-arid climates,

100-409: A mean annual temperature of 18 °C (64.4 °F) is used as an isotherm. A location with a BS -type climate is classified as hot semi-arid ( BSh ) if its mean temperature is above this isotherm, and cold semi-arid ( BSk ) if not. Hot semi-arid climates (type "BSh") tend to be located from the high teens to mid-30s latitudes of the tropics and subtropics , typically in proximity to regions with

125-534: 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. 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

150-654: A short distance or on satellite maps. From east to west, the High Plains rise in elevation from around 1,500 to 6,000 ft (460 to 1,830 m). 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 , brought

175-795: Is a dry climate sub-type. It is located on regions that receive precipitation below potential evapotranspiration , but not as low as a desert climate . There are different kinds of semi-arid climates, depending on variables such as temperature, and they give rise to different biomes . A more precise definition is given by the Köppen climate classification , which treats steppe climates ( BSh and BSk ) as intermediates between desert climates (BW) and humid climates (A, C, D) in ecological characteristics and agricultural potential. Semi-arid climates tend to support short, thorny or scrubby vegetation and are usually dominated by either grasses or shrubs as they usually cannot support forests. To determine if

200-413: 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. 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

225-464: Is the world record for the greatest temperature change in 24 hours. 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

250-755: The ABC Islands , the rain shadows of Hispaniola 's mountain ranges in the Dominican Republic and Haiti , parts of the Southwestern United States including California's Central Valley , and sections of South America such as the sertão , the Gran Chaco , and the poleward side of the arid deserts, where they typically feature a Mediterranean precipitation pattern, with generally rainless summers and wetter winters. They are also found in few areas of Europe surrounding

275-477: 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 by about one mile. Typical plant communities of

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300-673: The Larimer - Weld county line, the road drops noticeably from the Upper Cretaceous sandstone of the Plains to the lower shale of the Piedmont. The transition from High Plains to Piedmont is likewise accompanied by a change in agriculture, from pasture lands on the Plains to cultivated fields in the Piedmont. In the 19th century, the Piedmont region was inhabited primarily by the Southern Arapaho and Cheyenne tribes. From

325-599: The Mediterranean Basin . In Europe, BSh climates are predominantly found in southeastern Spain . It can also be found primarily in parts of south Greece but also in marginal areas of Thessaloniki and Chalkidiki in north Greece , most of Formentera , marginal areas of Ibiza and marginal areas of Italy in Sicily , Sardinia and Lampedusa . Cold semi-arid climates (type "BSk") tend to be located in elevated portions of temperate zones generally from

350-523: The Outback surrounding the central desert regions lies within the hot semi-arid climate region. In South Asia, both India and parts of Pakistan experience the seasonal effects of monsoons and feature short but well-defined wet seasons , but are not sufficiently wet overall to qualify as either a tropical savanna or a humid subtropical climate. Hot semi-arid climates can be also found in parts of North America , such as most of northern Mexico ,

375-795: The Cache la Poudre and other rivers, as well as the Colorado-Big Thompson Project , also supply needed water to the region. High Plains (United States) The High Plains are a subregion of the Great Plains , mainly 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

400-456: The High Plains commonly experience wide ranges and extremes in temperature. The temperature range from day to night is usually 30 °F (~16.5 °C), and 24-hour temperature shifts of 100 °F (~55.5 °C) are possible, as evidenced by a weather event that occurred in Browning, Montana , from January 23–24, 1916, when the temperature fell from 44 to −56 °F (7 to −49 °C). This

425-571: The Plains, rerouted northward along the mountains to join the Cache la Poudre River . In some areas of the Piedmont, a loose veneer of Pleistocene gravel overlays older shale and which accumulated during glaciation in the mountains, when streams descending onto the Piedmont became overburdened with sediment. The drop off from the Plains to the Piedmont is noticeable to motorists driving southward from Cheyenne, Wyoming on Interstate 25 . At approximately Mile 293 northeast of Wellington, Colorado , near

450-454: The country after Alaska . In contrast to the stagnant population growth in the northern and western High Plains, cities in west Texas have shown sustained growth; Amarillo and Lubbock both have populations above 200,000 and have continued to grow. Smaller towns, on the other hand, often struggle to sustain their population . Semi-arid climate#Cold semi-arid climates A semi-arid climate , semi-desert climate , or steppe climate

475-470: The earliest time of white settlement in the middle 19th century, the issue of water has been a controlling force in the economy of the region. The use of irrigation in the Piedmont starting in the 1860s led to widespread homesteading and cultivation of wheat and sugar beets, as well as cattle and sheep ranching. Much of the irrigation water in the Piedmont comes from shallow wells that tap the layers of Pleistocene gravel. Water diversion projects, locally from

500-667: The eastern side of the Rocky Mountains . The erosion scraped away the top layer of Upper Cretaceous sandstone (which still exists as the top layer on the High Plains), exposing the underlying layer of Pierre Shale , which had been formed during the Cretaceous, when a shallow sea covered present-day Colorado. It was during this time that the South Platte River, which had previously flowed eastward across

525-525: The mid-30s to low 50s latitudes, typically bordering a humid continental climate or a Mediterranean climate . They are also typically found in continental interiors some distance from large bodies of water. Cold semi-arid climates usually feature warm to hot dry summers, though their summers are typically not quite as hot as those of hot semi-arid climates. Unlike hot semi-arid climates, areas with cold semi-arid climates tend to have cold and possibly freezing winters. These areas usually see some snowfall during

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550-428: The region are shortgrass prairie , prickly pear cacti and scrub . Sagebrush steppe is also present, particularly in high and dry areas closer to the Rocky Mountains. Agriculture in the forms of cattle ranching and the growing of wheat , corn , and sunflower is the primary economic activity in the region. The region's aridity necessitates either dryland farming methods or irrigation; much water for irrigation

575-626: The region reaches the Rocky Mountains . The High Plains are located in eastern Montana , southeastern Wyoming , southwestern South Dakota , western Nebraska , eastern Colorado , western Kansas , eastern New Mexico , the Oklahoma Panhandle , and the Texas Panhandle . The southern region of the Western High Plains ecology region contains the geological formation known as Llano Estacado which can be seen from

600-536: 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. Today, the term "High Plains" is usually used for a subregion instead of the whole of the Great Plains. The High Plains has a "cold semi-arid" climate — Köppen BSk —receiving between 10–20 in (250–510 mm) of precipitation annually. Due to low moisture and high elevation,

625-796: The winter, though snowfall is much lower than at locations at similar latitudes with more humid climates. Areas featuring cold semi-arid climates tend to have higher elevations than areas with hot semi-arid climates, and tend to feature major temperature swings between day and night, sometimes by as much as 20 °C (36 °F) or more. These large diurnal temperature variations are seldom seen in hot semi-arid climates. Cold semi-arid climates at higher latitudes tend to have dry winters and wetter summers, while cold semi-arid climates at lower latitudes tend to have precipitation patterns more akin to Mediterranean climates , with dry summers, relatively wet winters, and even wetter springs and autumns. Cold semi-arid climates are most commonly found in central Asia and

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