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The Mojave Desert (pronounced: mo-hah-vee) is a rain shadow, mostly high desert area, that occupies a significant portion of southeastern California and smaller parts of central California, southern Nevada, southwestern Utah and northwestern Arizona in the United States. The Mojave Desert's boundaries are generally defined by the presence of ''Yucca brevifolia'' (Joshua trees), considered an indicator species for this desert. It is the driest of the North American deserts.〔 The desert is believed to support between 1,750 and 2,000 species of plants.〔Mazzucchelli, Vincent G., "The Southern Limits of the Mohave Desert, California", ''The California Geographer'', 1967, VIII: 127–133. This study provides original maps of the Mohave and adjacent deserts in the southwestern states.〕 It is roughly rectangular in shape,〔 bounded by the Great Basin Desert to the north,〔Mojave Desert Wildflowers, Pam MacKay, 2nd Ed. 2013, p. 1〕 and the Sonoran Desert to the south〔 and east. The topographical boundaries include the Tehachapi Mountains to the west, and the San Gabriel Mountains and San Bernardino Mountains to the south. The mountain boundaries are quite distinct since they are outlined by the two largest faults in California, the San Andreas and Garlock faults. The Mojave Desert displays typical basin and range topography. Higher elevations above 2,000 feet (610 m) in the Mojave are commonly referred to as the High Desert; however, Death Valley is the lowest elevation in North America at 282 feet (86 m) below sea level and is one of the Mojave Desert's more notorious places. It occupies less than 50,000 square miles, making it the smallest of the North American deserts.〔 The Mojave Desert is often referred to as the "high desert", in contrast to the "low desert", the Sonoran Desert to the south. The Mojave Desert is generally lower than the Great Basin Desert to the north. The term ''Mojave'' originates from the Spanish language while the spelling ''Mohave'' comes from modern English. Both are used today, although the Mohave Tribal Nation officially uses the spelling Mojave; the word is a shortened form of Hamakhaave, their endonym in their native language, which means 'beside the water'. While most of the Mojave Desert is sparsely populated, several large cities can be found there including Lancaster, Palmdale and Victorville in California, Henderson and Las Vegas (the largest) in Nevada, as well as St. George in Utah. There are some research facilities at Mojave Airport (also known as Mojave Air and Space Port), located within Mojave Desert. ==Climate== The Mojave Desert receives fewer than of rain a year and is generally between in elevation. The Mojave Desert also contains the Mojave National Preserve; as well as the lowest and hottest place in North America: Death Valley at 282 feet below sea level; where the temperature often surpasses from late June to early August. Zion National Park in Utah lies at the junction of the Mojave, the Great Basin Desert, and the Colorado Plateau. Despite its aridity, the Mojave (and particularly the Antelope Valley in its southwest) has long been a center of alfalfa production; fed by irrigation coming from groundwater and (in the 20th century) from the California Aqueduct. The Mojave is a desert of temperature extremes and two distinct seasons. Winter months bring temperatures dipping to around on valley floors, and below at higher elevations. Storms moving from the Pacific Northwest can bring rain and in some places even snow. More often, the rain shadow created by the Sierra Nevada as well as mountain ranges within the desert such as the Spring Mountains, bring only clouds and wind. In longer periods between storm systems, winter temperatures in valleys can approach . Spring weather continues to be influenced by Pacific storms, but rainfall is more widespread and occurs less frequently after April. By early June, it is rare for another Pacific storm to have a significant impact on the region's weather; and temperatures after the middle of May are normally above and frequently above . Summer weather is dominated by heat. Temperatures on valley floors can soar above and above at the lowest elevations. Low humidity, high temperatures, and low pressure, draw in moisture from the Gulf of Mexico creating thunderstorms across the desert southwest known as the North American monsoon. While the Mojave does not get nearly the amount of rainfall that the Sonoran desert to the south receives, monsoonal moisture will create thunderstorms as far west as California's Central Valley from mid-June through early September. Autumn is generally pleasant, with one to two Pacific storm systems creating regional rain events. October is one of the driest and sunniest months in the Mojave; and temperatures usually remain between and on the valley floors. After temperature, wind is the most significant weather phenomenon in the Mojave. Across the region windy days are common; and also common in areas near the transition between the Mojave and the California low valleys, including near Cajon Pass, Soledad Canyon and the Tehachapi areas. During the June Gloom, cooler air can be pushed out into the desert from Southern California. In Santa Ana wind events, hot air from the desert blows out into the Los Angeles basin and other coastal areas. Wind farms in these areas generate power from these winds. The other major weather factor in the region is elevation. The highest peak within the Mojave is Charleston Peak at ;〔 while the Badwater Basin in Death Valley is below sea level.〔 Accordingly, temperature and precipitation ranges wildly in all seasons across the region. The Mojave Desert has not historically supported a fire regime because of low fuel loads and connectivity. However, in the last few decades, invasive annual plants (e.g., ''Bromus'' spp., ''Schismus'' spp., ''Brassica'' spp.) have facilitated fire; which has significantly altered many areas of the desert. At higher elevations, fire regimes are regular but infrequent. 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「Mojave Desert」の詳細全文を読む スポンサード リンク
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