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The Coachella Valley (, )〔http://www.languagehat.com/archives/001249.php which quotes ''California Place Names: The Origin and Etymology of Current Geographical Names'', Gudde and Bright〕 is a desert valley in Southern California which extends for approximately in Riverside County southeast from the San Bernardino Mountains to the northern shore of the Salton Sea. It is the northernmost extent of the vast trough which includes the Salton Sea, the Imperial Valley and the Gulf of California. It is approximately wide along most of its length, bounded on the west by the San Jacinto Mountains and the Santa Rosa Mountains and on the north and east by the Little San Bernardino Mountains. The San Andreas Fault crosses the valley from the Chocolate Mountains in the southeast corner and along the centerline of the Little San Bernardinos. The fault is easily visible along its northern length as a strip of greenery against an otherwise bare mountain. The Chocolate Mountains are home to a United States Navy live gunnery range and are mostly off-limits to the public. In comparison to the "Inland Empire (IE)" (Riverside-San Bernardino area and the California desert), some people refer to the IE's sub-region Coachella Valley as the "Desert Empire" to differentiate it from the neighboring Imperial Valley. Geographers and geologists sometimes call the area, along with the Imperial Valley to the south, the "Cahuilla Basin" or the "Salton Trough".〔()〕 The valley connects with the Greater Los Angeles area to the west via the San Gorgonio Pass, a major transportation corridor that includes I-10 and the Union Pacific Railroad. The valley is part of the 13th-largest metropolitan area in the United States, the Inland Empire metropolitan area. The famous desert resort cities of Palm Springs and Palm Desert lie in the Coachella Valley. The Coachella Valley is the second largest sub-region in the Inland Empire, after the Greater San Bernardino Area which may be due to the number of seasonal residents in the winter months which at peak times may surpass 100,000 with another 3.5 million annual conventioneers and tourists. ==Geography and climate== The area is surrounded on the southwest by the Santa Rosa Mountains, by the San Jacinto Mountains to the west, the Little San Bernardino Mountains to the east and San Gorgonio Mountain to the north. These mountains peak at around and tend to average between 5,000 to 7,000 feet (1,500 to 2,000 m). Elevations on the Valley floor range from 1600 ft above sea level at the north end of the Valley to 250 ft below sea level around Mecca.〔(Coachella Valley | Coachella Valley Climate | Agriculture | Soils | Water )〕 In the summer months daytime temperatures range from to and nighttime lows from to . During winter, the daytime temperatures range from to and corresponding nights range from to making it a popular winter resort destination. The surrounding mountains create Thermal Belts in the immediate foothills of the Coachella Valley, leading to higher night-time temperatures in the winter months, and lower daytime temps during the summer months. Due to its warm year-round climate the region's agricultural sector produces fruits such as mangoes, figs and dates. The Valley is the northwestern extension of the Sonoran Desert to the southeast, and as such, is extremely arid. Most precipitation falls during the winter months from passing mid-latitude frontal systems from the north and west, nearly all of it as rain, but with snow atop the surrounding mountains. Rain also falls during the summer months as surges of moisture from both the Gulf of Mexico and the Gulf of California are drawn into the area by the desert monsoon. Occasionally, the remnants of a Pacific tropical cyclone can also affect the valley. In 1976, Tropical Storm Kathleen brought torrential rain and catastrophic flooding to the Coachella Valley as it swept in from the Pacific, traversing the region from south to north. Although the irrigation of over of the Valley since the early 20th century has allowed widespread agriculture. In its 2006 annual report, the Coachella Valley Water District listed the year's total crop value at over $576 million or almost $12,000 per acre.〔(Annual Water Quality Report ), cvwd.org. Retrieved August 2011〕 The Coachella Canal, a concrete-lined aqueduct built between 1938 and 1948 as a branch of the All-American Canal, brings water from the Colorado River to the Valley. The Colorado River Aqueduct, which provides drinking water to Los Angeles and San Diego, crosses the northeast end of the Valley along the base of the Little San Bernardino Mountains (the Joshua Tree National Park). The San Andreas Fault traverses the Valley's east side. Because of this fault, the Valley has many hot springs. The Santa Rosa Mountains to the West are part of the Elsinore Fault Zone. The results of a prehistoric sturzstrom can be seen in Martinez Canyon. The Painted Canyons of Mecca feature smaller faults as well as Precambrian, Tertiary and Quaternary rock formations, unconformities, badlands and desert landforms. Seismic activity is what triggers earthquakes, a natural, but occasionally destructive phenomena in the Coachella Valley. Fault lines cause hot water springs or geysers to rise from the ground. These natural water sources made habitation and development possible in the otherwise inhospitable desert environment of the Coachella Valley. Major earthquakes have affected the Coachella Valley. For instance, the 1992 Landers earthquake caused some damage in the valley. An earthquake of local origin which caused considerable damage was the 1986 North Palm Springs earthquake, which registered at a magnitude of 6.0, injuring 29 people and destroying 51 homes.〔(【引用サイトリンク】title=Historic Earthquakes )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Coachella Valley」の詳細全文を読む スポンサード リンク
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