Death Valley National Park, USAi

Regional Level Types
Death Valley National Park	National Park
USA	Country

Death Valley National Park is an American national park that straddles the California–Nevada border, east of the Sierra Nevada. The park boundaries include Death Valley, the northern section of Panamint Valley, the southern section of Eureka Valley and most of Saline Valley.

The park occupies an interface zone between the arid Great Basin and Mojave deserts, protecting the northwest corner of the Mojave Desert and its diverse environment of salt flats, sand dunes, badlands, valleys, canyons and mountains.

Death Valley is the largest national park in the contiguous United States, as well as the hottest, driest and lowest of all the national parks in the United States. It contains Badwater Basin, the second-lowest point in the Western Hemisphere and lowest in North America at 282 feet (86 m) below sea level. More than 93% of the park is a designated wilderness area.

The park is home to many species of plants and animals that have adapted to the harsh desert environment including creosote bush, Joshua tree, bighorn sheep, coyote, and the endangered Death Valley pupfish, a survivor from much wetter times. UNESCO included Death Valley as the principal feature of its Mojave and Colorado Deserts Biosphere Reserve in 1984.

A series of Native American groups inhabited the area from as early as 7000 BC, most recently the Timbisha around 1000 AD who migrated between winter camps in the valleys and summer grounds in the mountains. A group of European Americans, trapped in the valley in 1849 while looking for a shortcut to the gold fields of California, gave the valley its name, even though only one of their group died there.

Several short-lived boom towns sprang up during the late 19th and early 20th centuries to mine gold and silver. The only long-term profitable ore to be mined was borax, which was transported out of the valley with twenty-mule teams. The valley later became the subject of books, radio programs, television series, and movies. Tourism expanded in the 1920s when resorts were built around Stovepipe Wells and Furnace Creek. Death Valley National Monument was declared in 1933 and the park was substantially expanded and became a national park in 1994.

The natural environment of the area has been shaped largely by its geology. The valley is actually a graben with the oldest rocks being extensively metamorphosed and at least 1.7 billion years old. Ancient, warm, shallow seas deposited marine sediments until rifting opened the Pacific Ocean. Additional sedimentation occurred until a subduction zone formed off the coast. The subduction uplifted the region out of the sea and created a line of volcanoes. Later the crust started to pull apart, creating the current Basin and Range landform. Valleys filled with sediment and, during the wet times of glacial periods, with lakes, such as Lake Manly.

Death Valley is the fifth-largest American national park and the largest in the contiguous United States. It is also larger than the states of Rhode Island and Delaware combined, and nearly as large as Puerto Rico. In 2013, Death Valley National Park was designated as a dark sky park by the International Dark-Sky Association.

Geographic setting
There are two major valleys in the park, Death Valley and Panamint Valley. Both of these valleys were formed within the last few million years and both are bounded by north–south-trending mountain ranges. These and adjacent valleys follow the general trend of Basin and Range topography with one modification: there are parallel strike-slip faults that perpendicularly bound the central extent of Death Valley. The result of this shearing action is additional extension in the central part of Death Valley which causes a slight widening and more subsidence there.

Uplift of surrounding mountain ranges and subsidence of the valley floor are both occurring. The uplift on the Black Mountains is so fast that the alluvial fans (fan-shaped deposits at the mouth of canyons) there are small and steep compared to the huge alluvial fans coming off the Panamint Range. Fast uplift of a mountain range in an arid environment often does not allow its canyons enough time to cut a classic V-shape all the way down to the stream bed. Instead, a V-shape ends at a slot canyon halfway down, forming a 'wine glass canyon.' Sediment is deposited on a small and steep alluvial fan.

At 282 feet (86 m) below sea level at its lowest point, Badwater Basin on Death Valley's floor is the second-lowest depression in the Western Hemisphere (behind Laguna del Carbón in Argentina), while Mount Whitney, only 85 miles (137 km) to the west, rises to 14,505 feet (4,421 m) and is the tallest mountain in the contiguous United States. This topographic relief is the greatest elevation gradient in the contiguous United States and is the terminus point of the Great Basin's southwestern drainage. Although the extreme lack of water in the Great Basin makes this distinction of little current practical use, it does mean that in wetter times the lake that once filled Death Valley (Lake Manly) was the last stop for water flowing in the region, meaning the water there was saturated in dissolved materials. Thus, the salt pans in Death Valley are among the largest in the world and are rich in minerals, such as borax and various salts and hydrates. The largest salt pan in the park extends 40 miles (64 km) from the Ashford Mill Site to the Salt Creek Hills, covering some 200 square miles (520 km²) of the valley floor. The best-known playa in the park is the Racetrack, known for its moving rocks.

Climate
According to the Köppen climate classification system, Death Valley National Park has a hot desert climate (BWh). The plant hardiness zone at Badwater Basin is 9b with an average annual extreme minimum temperature of 28.0 °F (–2.2 °C).

Death Valley is the hottest and driest place in North America due to its lack of surface water and low relief. It is so frequently the hottest spot in the United States that many tabulations of the highest daily temperatures in the country omit Death Valley as a matter of course.

On the afternoon of July 10, 1913, the United States Weather Bureau recorded a high temperature of 134 °F (56.7 °C) at Greenland Ranch (now Furnace Creek) in Death Valley. This temperature stands as the highest ambient air temperature ever recorded at the surface of the Earth. (A report of a temperature of 58 °C (136.4 °F) recorded in Libya in 1922 was later determined to be inaccurate.) Daily summer temperatures of 120 °F (49 °C) or greater are common, as well as below-freezing nightly temperatures in the winter. July is the hottest month, with an average high of 117 °F (47 °C) and an average low of 91 °F (33 °C). December is the coldest month, with an average high of 66 °F (19 °C) and an average low of 41 °F (5 °C). The record low is 15 °F (−9.4 °C). There are an average of 197.3 days annually with highs of 90 °F (32.2 °C) or higher and 146.9 days annually with highs of 100 °F (37.8 °C) or higher. Freezing temperatures of 32 °F (0 °C) or lower occur on an average of 8.6 days annually.

Several of the larger Death Valley springs derive their water from a regional aquifer, which extends as far east as southern Nevada and Utah. Much of the water in this aquifer has been there for many thousands of years, since the Pleistocene ice ages, when the climate was cooler and wetter. Today's drier climate does not provide enough precipitation to recharge the aquifer at the rate at which water is being withdrawn.

The highest range within the park is the Panamint Range, with Telescope Peak being its highest point at 11,049 feet (3,368 m). The Death Valley region is a transitional zone in the northernmost part of the Mojave Desert and consists of five mountain ranges removed from the Pacific Ocean. Three of these are significant barriers: the Sierra Nevada, the Argus Range, and the Panamint Range. Air masses tend to lose moisture as they are forced up over mountain ranges, in what climatologists call a rainshadow effect.

The exaggerated rain shadow effect for the Death Valley area makes it North America's driest spot, receiving about 1.5 inches (38 mm) of rainfall annually at Badwater, and some years fail to register any measurable rainfall. Annual average precipitation varies from 1.92 inches (49 mm) overall below sea level to over 15 inches (380 mm) in the higher mountains that surround the valley. When rain does arrive it often does so in intense storms that cause flash floods which remodel the landscape and sometimes create very shallow ephemeral lakes.

The hot, dry climate makes it difficult for soil to form. Mass wasting, the down-slope movement of loose rock, is therefore the dominant erosive force in mountainous areas, resulting in "skeletonized" ranges (mountains with very little soil on them). Sand dunes in the park, while famous, are not nearly as widespread as their fame or the dryness of the area may suggest. The Mesquite Flat dune field is the most easily accessible from the paved road just east of Stovepipe Wells in the north-central part of the valley and is primarily made of quartz sand. Another dune field is just 10 miles (16 km) to the north but is instead mostly composed of travertine sand. The highest dunes in the park, and some of the highest in North America, are located in the Eureka Valley about 50 miles (80 km) to the north of Stovepipe Wells, while the Panamint Valley dunes and the Saline Valley dunes are located west and northwest of the town, respectively. The Ibex dune field is near the seldom-visited Ibex Hill in the southernmost part of the park, just south of the Saratoga Springs marshland. All the latter four dune fields are accessible only via unpaved roads. Prevailing winds in the winter come from the north, and prevailing winds in the summer come from the south. Thus, the overall position of the dune fields remains more or less fixed.

There are rare exceptions to the dry nature of the area. In 2005, an unusually wet winter created a 'lake' in the Badwater Basin and led to the greatest wildflower season in the park's history. In October 2015, a "1000-year flood event" with over three inches of rain caused major damage in Death Valley National Park. A similar widespread storm in August 2022 damaged pavement and deposited debris on nearly every road, trapping 1,000 residents and visitors overnight. ⓘ Adamiteⓘ Albite ⓘ Albite var. Andesine ⓘ Albite var. Oligoclase ⓘ 'Allanite Group' ⓘ Almandine ⓘ Altaite ⓘ Alunogenⓘ Analcime