Английская Википедия:Alvord Desert

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The Alvord Desert is a desert located in Harney County, in southeastern Oregon in the Western United States. It is roughly southeast of Steens Mountain. The Alvord Desert is a Шаблон:Convert dry lake bed and averages Шаблон:Convert of rain a year. Two mountain ranges separate it from the Pacific Ocean—the Coast Range, and the Cascade Mountains. Along with Steens Mountain, these topographical features create a rain shadow. The Alvord Desert lies at an elevation of approximately Шаблон:Convert.

During the dry season the surface is sufficiently flat for driving or landing small aircraft. Vehicle driving attempts to score land speed records are performed on the dry lake bed. The women's world land speed record was set in 1976 by Kitty O'Neil at Шаблон:Convert, later surpassed in 2019 by Jessi Combs at Шаблон:Convert, although the latter died in the process because of a crash.

The nearest community is Fields, Oregon.

Name

The desert is named after General Benjamin Alvord, who served as commander of the U.S. Army's Department of Oregon during the American Civil War.

Climate

Шаблон:Climate chart The Alvord Desert experiences a cold desert climate (Köppen BWk). The area receives very little rainfall throughout the year due to the rain shadow created by the Coast and Cascade mountain ranges as well the adjacent Steens Mountain. Some eastern areas of the desert may receive as little as Шаблон:Convert of rain annually.

Winter

Winter temperatures in the Alvord Basin are moderated through airflow from the south that stops the temperature from dropping too heavily. While many areas in the Oregon High Desert frequently dip below Шаблон:Convert through the winter months, the Alvord Desert rarely sees these frigid temperatures. On average, highs will commonly reach between Шаблон:Convert, with a few rare instances where the temperature fails to break Шаблон:Convert. At night, the temperature falls to between Шаблон:Convert, but will not normally fall much further unless Arctic air masses arrive. The basin sees a moderate amount of its rainfall in the winter months from storms coming off the Pacific Ocean while the strong winter jet stream is aimed at the Pacific Northwest. Storms that are strong enough to bring moisture to the Southeastern area of Oregon are usually related to tropical storms feeding from the Hawaiian Islands. Snow does sometimes occur in the rare instances when cold air from the arctic to the north meets a strong flow of moisture from the Pacific to the West.

Spring

Spring is when the bulk of precipitation falls from thunderstorms. These storms attribute to the rainfall in April, May, and June that form in the south and move their way north across the desert and surrounding sagebrush plains. Clear nights continue to bring cold overnight temperatures which commonly drop to between Шаблон:Convert, but afternoon warming raises temperatures to between Шаблон:Convert in early spring and Шаблон:Convert in late spring. This warming can help trigger thunderstorms in combination with the unstable spring atmosphere. Extremes in temperature can still be seen at this time of year where temperatures have fallen to Шаблон:Convert in March, and climbed to over Шаблон:Convert in early June. Rainfall turns the playa into a small lake, and for a short time, makes travel across it difficult.

Summer

Summer in the Alvord Desert has some of the hottest temperatures in the state of Oregon. High pressure sets in over the Pacific Northwest and the jet stream pushes north into Canada. This high pressure means very little precipitation, averaging less than Шаблон:Convert throughout the summer months. Late day heat begins to set in by late June where highs reach between Шаблон:Convert. In July the temperature commonly climbs to between Шаблон:Convert. Night-time lows vary, with overnight temperatures dropping down between Шаблон:Convert throughout much of the basin. In some locations temperatures will only drop to between Шаблон:Convert. August remains hot with highs ranging between Шаблон:Convert and lows between Шаблон:Convert, though dropping towards the end of the month.

Fall

Fall is moderate with high temperatures ranging between Шаблон:Convert and lows between Шаблон:Convert. Fall is also one of the driest times of the year.

Geology

Three primary geothermal areas are along the western edge as well as cold springs following NE to SW trending normal faults. On the western edge of the desert is Alvord Hot Springs (Шаблон:Coord). At the north is Mickey Hot Springs (Шаблон:Coord): an assortment of bubbling mud, pools and, the occasional geyser. At the south is Borax Lake (Шаблон:Coord) which is a thermal spring complex. To the east is an unnamed natural hot spring, one of 40 or more along Шаблон:Convert of the Alvord fault. To the southwest is seasonal alkali Alvord Lake which once extended Шаблон:Convert north and south—covering the desert. Several of the geothermal features in Alvord Desert Basin have been examined by a team of scientists and geologists from the University of Idaho, Boise State University, and Idaho State University.

Fauna

Despite the barren nature of the playa, some opportunities for wildlife observation exist. Wild horses sometimes drink from the springs on the eastern edge of the desert. In areas where natural hot springs flow into the playa, especially around the Alvord Hot Springs, one can usually find nesting long-billed curlew. Further out into the playa proper are numerous killdeer and snowy plover, along with the occasional American avocet. The outlet waters from the springs typically flow roughly one mile into the desert, and their reach roughly delineates the bird habitat. The nearby Steens Mountain Wilderness contains populations of bighorn sheep, mule deer, elk, and pronghorn. Further west is the Malheur National Wildlife Refuge, which is popular for birding.

Land speed record

The previous women's Land Speed Record was set at Alvord Desert by Kitty O'Neil, in the jet-powered SMI Motivator, in 1976. O'Neil reached Шаблон:Convert.

On August 27, 2019, Jessi Combs died while making back and forth runs at Alvord Desert in an attempt to break O'Neil's record, and in June 2020, Guinness World Records recognized Combs' runs on that date as the official new world record of Шаблон:Convert.

Gallery

• Setting sun reflected off the playa

  Setting sun reflected off the playa

• Steens Mountain to the northwest from the Alvord Desert

  Steens Mountain to the northwest from the Alvord Desert

• Close-up of the surface, June 2018

  Close-up of the surface, June 2018

External links

• Alvord Desert - Bureau of Land Management
• Шаблон:Oregon Encyclopedia
• The Wilderness Society: Wilderness in Oregon’s High Desert
• Alvord Desert Gliders Video produced by Oregon Field Guide