Grand Canyon

From Wikipedia, the free encyclopedia

This article is about the canyon in the southwestern United States. For other Grand Canyons, see Grand Canyon (disambiguation).

Geography

Apollo Throne in sunset light from the South Rim of the Grand Canyon at Moran Point.

The Grand Canyon is a massive rift in the Colorado Plateau that exposes uplifted Proterozoic and Paleozoic strata, and is also one of the six distinct physiographic sections of the Colorado Plateau province. The Grand Canyon is unmatched throughout the world for the vistas it offers to visitors on the rim. It is not the deepest canyon in the world; Kali Gandaki Gorge in Nepal is far deeper, nor the widest (Capertee Valley in Australia is about 1 km wider and longer than Grand Canyon), not to mention the largest — but the Grand Canyon is known for its overwhelming size and its intricate and colorful landscape. Geologically it is significant because of the thick sequence of ancient rocks that are beautifully preserved and exposed in the walls of the canyon. These rock layers record much of the early geologic history of the North American continent.

Temples, Castles, and Shrines.

Uplift associated with mountain building events later moved these sediments thousands of feet upward and created the Colorado Plateau. The higher elevation has also resulted in greater precipitation in the Colorado River drainage area, but not enough to change the Grand Canyon area from being semi-arid. The uplift of the Colorado Plateau is uneven, and the north-south trending Kaibab Plateau that Grand Canyon bisects is over a thousand feet higher at the North Rim (about 1,000 ft/300 m) than at the South Rim. The fact that the Colorado River flows in a curve around the higher North Rim part of the Kaibab Plateau and closer to the South Rim part of the plateau is also explained by this asymmetry. Ivo Lucchitta of the U.S. Geological Survey first suggested that, as the Colorado River developed before significant erosion of the region, it naturally found its way across or around the Kaibab Uplift by following a "racetrack" path to the south of the highest part of the plateau. Almost all runoff from the North Rim (which also gets more rain and snow) flows toward the Grand Canyon, while much of the runoff on the plateau behind the South Rim flows away from the canyon (following the general tilt). The result is deeper and longer tributary washes and canyons on the north side and shorter and steeper side canyons on the south side.

Temperatures on the North Rim are generally lower than the South Rim because of the greater elevation (averaging 8,000 ft/2,438 m above sea level).^[6] Heavy rains are common on both rims during the summer months. Access to the North Rim via the primary route leading to the canyon (State Route 67) is limited during the winter season due to road closures. Views from the North Rim tend to give a better impression of the expanse of the canyon than those from the South Rim.

Geology

Main article: Geology of the Grand Canyon area

Diagram showing the placement, age and thickness of the rock units exposed in the Grand Canyon

The Colorado River basin (of which the Grand Canyon is a part) has developed in the past 40 million years. A recent study places the origins of the canyon beginning some 17 million years ago. Previous estimates had placed the age of the canyon at 5 to 6 million years. The study, which was published in 2008 in the journal Science utilized uranium-lead dating to analyze calcite deposits found on the walls of nine caves throughout the canyon.^[7] There is a substantial amount of controversy because this research suggests such a substantial departure from prior widely supported scientific consensus.^[8]

The result of all this erosion is one of the most complete geologic columns on the planet.

The major geologic exposures in the Grand Canyon range in age from the 2 billion year old Vishnu Schist at the bottom of the Inner Gorge to the 230 million year old Kaibab Limestone on the Rim. Interestingly, there is a gap of about one billion years between the stratum that is about 500 million years old and the lower level, which is about 1.5 billion years old. That indicates a period of erosion between two periods of deposition.

Many of the formations were deposited in warm shallow seas, near-shore environments (such as beaches), and swamps as the seashore repeatedly advanced and retreated over the edge of a proto-North America. Major exceptions include the Permian Coconino Sandstone, which most geologists interpret as an aeolian sand dune deposit and several parts of the Supai Group.

The great depth of the Grand Canyon and especially the height of its strata (most of which formed below sea level) can be attributed to 5,000 to 10,000 feet (1500 to 3000 m) of uplift of the Colorado Plateau, starting about 65 million years ago (during the Laramide Orogeny). This uplift has steepened the stream gradient of the Colorado River and its tributaries, which in turn has increased their speed and thus their ability to cut through rock (see the elevation summary of the Colorado River for present conditions).

Weather conditions during the ice ages also increased the amount of water in the Colorado River drainage system. The ancestral Colorado River responded by cutting its channel faster and deeper.

The base level and course of the Colorado River (or its ancestral equivalent) changed 5.3 million years ago when the Gulf of California opened and lowered the river's base level (its lowest point). This increased the rate of erosion and cut nearly all of the Grand Canyon's current depth by 1.2 million years ago. The terraced walls of the canyon were created by differential erosion.^[9]

About one million years ago, volcanic activity (mostly near the western canyon area) deposited ash and lava over the area, which at times completely obstructed the river. These volcanic rocks are the youngest in the canyon.

Human history

Main article: History of the Grand Canyon area

uebloan (The Ancient Ones, or Anasazi)

The Basketmakers view of the Colorado River flowing through the Grand Canyon.
The Ancestral P
The Pueblo Anasazi
Ancient Puebloan Occupation of the Grand Canyon
- Nankoweap Canyon
- The Unkar Delta (see Geology of the Grand Canyon area)
- The Bright Angel site
Ancient Pueblo Peoples leave the Canyon
- Beamer's Cabin
  - The Beamers Back Window

The Grand Canyon, as seen from river-level.

Eagle Rock (located at Eagle Point) on the west rim, aptly named for its shape, is considered sacred by the Hualapai Indians.

Other cultures

The Cohonina^[10]
The Sinagua
The Pai (The People)
The Hualapai (The People of the Pine Trees)
The Havasupai (The People of the blue-green water)
The Paiutes (The Water People)
The Dineh (The People)

European arrival and settlement

The Spanish explorers

In September 1540, under orders from the conquistador Francisco Vázquez de Coronado to search for the fabled Seven Cities of Cibola, Captain Garcia Lopez de Cardenas, along with Hopi guides and a small group of Spanish soldiers, traveled to the South Rim of the Grand Canyon between Desert View and Moran Point. Pablo de Melgrossa, Juan Galeras, and a third soldier descended some one third of the way into the Canyon until they were forced to return because of lack of water. In their report, they noted that some of the rocks in the Canyon were "bigger than the great tower of Seville."^[11] It is speculated that their Hopi guides must have been reluctant to lead them to the river, since they must have known routes to the canyon floor. Afterwards, no Europeans visited the Canyon for over two hundred years.

Fathers Francisco Atanasio Domínguez and Silvestre Vélez de Escalante were two Spanish Priests who, with a group of Spanish soldiers, explored southern Utah and traveled along the North Rim of the Canyon in Glen and Marble Canyons in search of a route from Santa Fe to California in 1776. They eventually found a crossing that today lies under Lake Powell.

Also in 1776, Fray Francisco Garces, a Franciscan missionary, spent a week near Havasupai, unsuccessfully attempting to convert a band of Native Americans. He described the Canyon as "profound".^[11]

American exploration

Noon rest in Marble Canyon, second Powell Expedition, 1872

James Ohio Pattie, along with a group of American trappers and mountain men, was probably the next European to reach the Canyon in 1826, although there is little documentation to support this.^[12] Jacob Hamblin (a Mormon missionary) was sent by Brigham Young in the 1850s to locate easy river crossing sites in the Canyon. Building good relations with local Native Americans and white settlers, he discovered Hope Dog in 1858 and Pierce Ferry (later operated by, and named for, Harrison Pierce) - the only two sites suitable for ferry operation.^{[citation needed]} He also acted as an advisor to John Wesley Powell before his second expedition to the Grand Canyon, acting as a diplomat between Powell and the local native tribes to ensure the safety of his party.

In 1857 Edward Fitzgerald Beale superintendent of an expedition to survey a wagon road along the 35th parallel from Fort Defiance to the Colorado river led a small party of men in search of water on the Coconino plateau on the south rim of the Grand Canyon. On September 19 near present day National Canyon they came upon what May Humphreys Stacey described in his journal as "...a wonderful canyon four thousand feet deep. Everyone (in the party) admitted that he never before saw anything to match or equal this astonishing natural curiosity."

Also in 1857, the U.S. War Department asked Lieutenant Joseph Ives to lead an expedition to assess the feasibility of an up-river navigation from the Gulf of California. Also in a stern wheeler steamboat "Explorer", after two months and 350 miles (560 km) of difficult navigation, his party reached Black Canyon some two months after George Johnson.^{[citation needed]} The "Explorer" struck a rock and was abandoned. Ives led his party east into the Canyon — they were the first Europeans to travel the Diamond Creek drainage and traveled eastwards along the South Rim.

In 1858, John Strong Newberry became probably the first geologist to visit the Grand Canyon.

In 1869, Major John Wesley Powell led the first expedition down the Grand Canyon.

The Brown-Stanton River Expedition
Other expeditions

Settlers in and near the canyon

Miners: "Captain" John Hance, William W. Bass, Louis Boucher "The Hermit", Seth Tanner, Charles Spencer, D. W. "James" Mooney
Lees Ferry: John Doyle Lee, Emma Lee French (17th of John Lee's 19 wives), J. S. Emmett, Charles Spencer
Phantom Ranch: David Rust, Mary Colter
Grand Canyon Village: Ralph H. Cameron

Federal protection

U.S. President Theodore Roosevelt visited the Grand Canyon in 1903. An avid outdoorsman and staunch conservationist, he established the Grand Canyon Game Preserve on November 28, 1906. Livestock grazing was reduced, but predators such as mountain lions, eagles, and wolves, were eradicated. Roosevelt added adjacent national forest lands and redesignated the preserve a U.S. National Monument on January 11, 1908. Opponents such as land and mining claim holders blocked efforts to reclassify the monument as a U.S. National Park for 11 years. Grand Canyon National Park was finally established as the 17th U.S. National Park by an Act of Congress signed into law by President Woodrow Wilson on February 26, 1919.^[13]

The federal government administrators who manage park resources face many challenges. These include issues related to the recent reintroduction into the wild of the highly endangered California Condor, air tour overflight noise levels, water rights disputes with various tribal reservations that border the park, and forest fire management. The Grand Canyon National Park superintendent is Steve Martin. Martin was named superintendent on February 5, 2007 to replace retiring superintendent Joe Alston. Martin was previously the National Park Service Deputy Director and superintendent of several other national parks including Denali and Grand Teton.^[14] Federal officials started a flood in the Grand Canyon in hopes of restoring its ecosystem on March 5, 2008. The canyon's ecosystem was permanently changed after the construction of the Glen Canyon Dam in 1963.^[15]

South Rim buildings

There are several historical buildings located along the South Rim; most are in Grand Canyon Village.

Desert View Watchtower in 2004

Buckey O'Neill Cabin was built during the 1890s by William Owen "Buckey" O'Neill. He built the cabin because of a copper deposit that was nearby. He had several occupations such as miner, judge, politician, author and tour guide. This cabin is the longest continually standing structure in the South Rim. It is currently used as a guest house; booking is required well in advance.

Kolb Studio was built in 1904 by brothers Ellsworth and Emery Kolb. They were photographers who made a living by photographing visitors walking down the Bright Angel Trail. In 1911, the Kolb brothers filmed their journey down the Green and Colorado Rivers. Emery Kolb showed this movie regularly in his studio until 1976, when he died at the age of 95. Today the building serves as an art gallery and exhibit.

The El Tovar Hotel was built in 1905 and is the most luxurious lodging on the South Rim. The hotel consists of 4 stories with a rustic chalet appearance. It was designed by Charles Whittlesley. A gift shop and restaurant are located inside the hotel.

Hopi House was built by Mary Jane Colter in 1905. It is based on structures that were built in an ancient Hopi settlement called Old Oraibi, located on the Third Mesa in eastern Arizona. It served as a residence for the Hopi Indians who sold arts and crafts to visitors in the South Rim.

Verkamp's Curios, which stands next to the Hopi House, was built by John Verkamp in 1905. He sold arts and crafts as well as souvenirs. Until September 2008, it was run by his descendants; in November 2008 the building reopened as a visitor center focusing on the history of the Grand Canyon Village community.

Grand Canyon Railway Depot was built in 1909 and contains 2 levels. While it is commonly said that this depot building is one of only three log-cabin-style train stations currently standing out of fourteen supposedly ever built in the U.S., this claim has never been verified. This claim originated in a 1985 document written by Gordon Chappell entitled "Statement on Architectural and Historic Significance" and is currently repeated, without verification, by newspapers, magazines and on-line articles, including ones appearing on the National Park Service website. The depot is the northern terminus of the Grand Canyon Railway which begins in Williams, Arizona.

Lookout Studio was built in 1914 and is another structure that was designed by Mary Colter. Photography artwork, books, souvenirs, and rock and fossil specimens are sold here. A great view of Bright Angel Trail can be seen here.

Desert View Watchtower was built in 1932 and is one of Mary Colter's best-known works. Situated at the far eastern end of the South Rim, 27 miles (43 km) from Grand Canyon Village, the tower sits on a 7,400 foot (2,256 m) promontory. It offers one of the few views of the bottom of the Canyon and the Colorado River. It is designed to mimic an Anasazi watchtower though it is larger than existing ones.^[16]

Bright Angel Lodge was built of logs and stone in 1935. Mary Colter designed the lodge and it was built by Fred Harvey. Inside the lodge is a small museum honoring Fred Harvey, who played a major role in popularizing the Grand Canyon. In the history room is a fireplace that is made of stone from the South Rim that is layered in the same sequence as in the canyon.

Weather

Weather in the Grand Canyon varies according to elevation.

A storm over the Grand

Canyon

The forested rims are high enough to receive winter snowfall, but along the Colorado River in the Inner Gorge, temperatures are similar to those found in Tucson and other low elevation desert locations in Arizona. Conditions in the Grand Canyon region are generally dry, but substantial precipitation occurs twice annually, during seasonal pattern shifts in winter (when Pacific storms usually deliver widespread, moderate rain and high-elevation snow to the region from the west) and in late summer (a phenomenon known as the monsoon, which delivers waves of moisture from the southeast, causing dramatic, localized thunderstorms fueled by the heat of the day).^[17] Average annual precipitation on the South Rim is less than 16 inches (35 cm), with 60 inches (132 cm) of snow, the higher North Rim usually receives 27 inches (59 cm) of moisture, with a typical snowfall of 144 inches (317 cm), and Phantom Ranch, far below the Canyon's rims along the Colorado River at 2,500 feet (762 m) gets just 8 inches (17.6 cm) of rain, and snow is a rarity. The weather is different on the north rim and south rim.

Grand Canyon covered with snow

Temperatures vary wildly throughout the year, with summer highs within the Inner Gorge commonly exceeding 100 °F (37.8 °C) and winter minimum temperatures sometimes falling below zero degrees Fahrenheit (-17.8 °C) along the canyon's rims.^[17] Visitors are often surprised by these potentially extreme conditions, and this, along with the high altitude of the canyon's rims, can lead to unpleasant side effects such as dehydration, sunburn, and hypothermia. Be prepared for a variety of potential weather conditions when visiting, and keep in mind the Grand Canyon is a rugged natural feature located in a remote area subject to a wide range of environmental hazards.

Weather conditions can greatly affect hiking and canyon exploration, and visitors should obtain accurate forecasts because of hazards posed by exposure to extreme temperatures, winter storms and late summer monsoons. While the park service posts weather information at gates and visitor centers, this is a rough approximation only, and should not be relied upon for trip planning. For accurate weather in the Canyon, hikers should consult the National Weather Service's NOAA weather radio or the official National Weather Service website.^[18]

Air pollution

Brown cloud of air pollution visible from Yavapai Point, April 2007

The Grand Canyon has suffered some problems with air pollution, attributed to the nearby Navajo Generating Station, a coal-burning power plant. In 1991 an agreement was reached with the Navajo Generating Station in Page, Arizona, to add air pollution control devices to their smokestacks.^[19]

Biology and ecology

Plants

There are approximately 1,737 known species of vascular plants, 167 species of fungi, 64 species of moss and 195 species of lichen found in Grand Canyon National Park.^[20] This variety is largely due to the 8,000 foot elevation change from the Colorado River up to the highest point on the North Rim.^[20] Grand Canyon boasts a dozen endemic plants (known only within the Park's boundaries) while only ten percent of the Park's flora is exotic.^[20] Sixty-three plants found here have been given special status by the U.S. Fish and Wildlife Service.^[20]

The Mojave Desert influences the western sections of the canyon, Sonoran Desert vegetation covers the eastern sections, and ponderosa and pinyon pine forests grow on both rims.^[21]

Natural seeps and springs percolating out of the canyon walls are home to 11% of all the plant species found in the Grand Canyon.^[21] The Canyon itself can act as a connection between the east and the west by providing corridors of appropriate habitat along its length.^[21] The canyon can also be a genetic barrier to some species, like the Tassel-eared squirrel.^[21]

The aspect, or direction a slope faces, also plays a major role in adding diversity to the Grand Canyon. North-facing slopes receive about one-third the normal amount of sunlight, so plants growing there are similar to plants found at higher elevations, or in more northern latitudes.^[21] The south-facing slopes receive the full amount of sunlight and are covered in vegetation typical of the Sonoran Desert.^[21]

Animals

Of the 34 mammal species found along the Colorado River corridor, 15 are rodents and eight are bats.^[22]

Life zones and communities

The Park contains several major ecosystems.^[23] Its great biological diversity can be attributed to the presence of five of the seven life zones and three of the four desert types in North America.^[23] The five life zones represented are the Lower Sonoran, Upper Sonoran, Transition, Canadian, and Hudsonian.^[23] This is equivalent to traveling from Mexico to Canada. Differences in elevation and the resulting variations in climate are the major factors that form the various life zones and communities in and around the canyon. Grand Canyon National Park contains 129 vegetation communities, and the composition and distribution of plant species is influenced by climate, geomorphology and geology.^[20]

Lower Sonoran

A bighorn ewe at Grand Canyon, 2008

The Lower Sonoran life zone spans from the Colorado River up to 3500 feet. Along the Colorado River and its perennial tributaries, a riparian community exists.^[20] Coyote willow, arrowweed, seep willow, western honey mesquite, catclaw acacia, and exotic tamarisk (saltcedar) are the predominant species.^[20] Hanging gardens, seeps and springs often contain rare plants such as the white-flowering redbud tree, stream orchid, and McDougall's flaveria.^[20] Endangered fish in the river include the Humpback Chub and the Razorback Sucker.^[24]

The three most common amphibians in these riparian communities are the canyon treefrog, red-spotted toad, and Woodhouse’s rocky mountain toad.^[25] Leopard frogs are very rare in the Colorado River corridor, and are known to exist at only a few sites.^[25] There are 33 crustacean species found in the Colorado River and its tributaries within Grand Canyon National Park. Of these 33, 16 are considered true zooplankton organisms.^[26]

Only 48 bird species regularly nest along the river while others use the river as a migration corridor or as overwintering habitat. The Bald Eagle is one species that uses the river corridor as winter habitat.^[27]

River otters may have disappeared from the park in late 20th century and muskrats are extremely rare.^[22] Beavers cut willows, cottonwoods, and shrubs for food, and can significantly affect the riparian vegetation.^[22] Other rodents, such as antelope squirrels and pocket mice, are mostly omnivorous, using many different vegetation types.^[22] Grand Canyon bats typically roost in desert uplands, but forage on the abundance of insects along the river and its tributaries.^[22] In addition to bats, coyotes, ringtails, and spotted skunks are the most numerous riparian predators and prey on invertebrates, rodents, and reptiles.^[22]

Raccoon, weasel, bobcat, gray fox, and mountain lion are also present, but are much more rare.^[22] Mule deer and desert bighorn sheep are the ungulates that frequent the river corridor. Since the removal of 500 ferral burros in the early 1980s, bighorn sheep numbers have rebounded.^[22] Mule deer are generally not permanent residents along the river, but travel down from the rim when food and water resources there become scarce.^[22]

The insect species commonly found in the river corridor and tributaries are midges, caddis flies, mayflies, stoneflies, black flies, mites, beetles, butterflies, moths, and fire ants.^[28] Numerous species of spiders and several species of scorpions including the bark scorpion and the giant desert hairy scorpion inhabit the riparian zone.^[28]

Eleven aquatic and 26 terrestrial species of mollusks have been identified in and around Grand Canyon National Park.^[29] Of the aquatic species, two are bivalves (clams) and nine are gastropods (snails).^[29] Twenty-six species of terrestrial gastropods have been identified, primarily land snails and slugs.^[29]

There are a approximately 47 reptile species in Grand Canyon National Park. Ten are considered common along the river corridor and include lizards and snakes.^[30] Lizard density tends to be highest along the stretch of land between the water's edge and the beginning of the upland desert community.^[30] The two largest lizards in the Canyon are gila monsters and chuckwallas.^[30] Many snake species, which are not directly dependent on surface water, may be found both within the inner gorge and the Colorado River corridor. Six rattlesnake species have been recorded in the park.^[30]

Above the river corridor a desert scrub community, composed of North American desert flora, thrives. Typical warm desert species such as creosote bush, white bursage, brittle brush, catclaw acacia, ocotillo, mariola, western honey mesquite, four-wing saltbush, big sagebrush, blackbrush and rubber rabbitbrush grow in this community.^[20] The mammalian fauna in the woodland scrub community consists of 50 species, mostly rodents and bats.^[22] Three of the five Park woodrat species live in the desert scrub community.^[22]

Except for the desert banded gecko, which seems to be distributed only near water along the Colorado River, all of the reptiles found near the river also appear in the uplands, but in lower densities.^[30] The desert gopher tortoise, a threatened species, inhabits the desert scrublands in the western end of the park.^[30]

Some of the common insects found at elevations above 2,000 feet are orange paper wasps, honey bees, black flies, tarantula hawks, stink bugs, beetles, black ants, and monarch and swallowtail butterflies.^[28] Solpugids, wood spiders, garden spiders, black widow spiders and tarantulas can are found in the desert scrub and higher elevations.^[28]

Upper Sonoran and Transition

A California Condor in flight, photographed from Navajo Bridge at Marble Canyon, 2008. Wild condors are numbered to aid wildlife researchers. As of April 2009, there were 172 wild California condors known.

The Upper Sonoran Life Zone includes most of the inner canyon and South Rim at elevations from 3,500 to 7,000 feet.^[21] This zone is generally dominated by blackbrush, sagebrush, and pinyon-juniper woodlands. Elevations of 3,500 to 4,000 feet are in the Mojave Desert Scrub community of the Upper Sonoran. This community is dominated by the four-winged saltbush and creosote bush; other important plants include Utah agave, narrowleaf mesquite, ratany, catclaw, and various cacti species.^[21]

Approximately 30 bird species breed primarily in the desert uplands and cliffs of the inner canyon.^[27] Virtually all bird species present breed in other suitable habitats throughout the Sonoran and Mohave deserts.^[27] The abundance of bats, swifts, and riparian birds provides ample food for peregrines, and suitable eyrie sites are plentiful along the steep canyon walls. Also, several endangered California Condors that were re-introduced to the Colorado Plateau on the Arizona Strip, have made the eastern part of the Park their home.^[27]

The conifer forests provide habitat for 52 mammal species.^[22] Porcupines, shrews, red squirrels, tassel eared Kaibab and Abert's squirrels, black bear, mule deer, and elk are found at the park's higher elevations on the Kaibab Plateau.^[22]

Above the desert scrub and up to 6,200 feet is a pinyon pine, Utah and one seed juniper woodland.^[20] Within this woodland one can find big sagebrush, snakeweed, Mormon tea, Utah agave, banana and narrowleaf Yucca, winterfat, Indian ricegrass, dropseed, and needlegrass.^[20] There are a variety of snakes and lizards here, but one species of reptile, the mountain short-horned Lizard, is a particularly abundant inhabitant of the piñon-juniper and ponderosa pine forests.^[30]

Ponderosa pine forests grow at elevations between 6,500 feet and 8,200 feet, on both North and South rims in the Transition life zone.^[20] The South Rim is includes species such as gray fox, mule deer, bighorn sheep, rock squirrels, pinyon pine and Utah juniper.^[21] Additional species such as Gambel oak, New Mexico locust, mountain mahogany, elderberry, creeping mahonia, and fescue have been identified in these forests.^[20] The Utah tiger salamander and the Great Basin spadefoot toad are two amphibians that are common in the rim forests.^[25] Of the approximately 90 bird species that breed in the coniferous forests, 51 are summer residents and at least 15 of these are known to be neotropical migrants.^[27]

Canadian and Hudsonian

Elevations of 8,200 to 9,000 feet are in the Canadian Life Zone, which includes the North Rim and the Kaibab Plateau.^[21] Spruce-fir forests characterized by Englemann spruce, blue spruce, Douglas fir, white fir, aspen, and mountain ash, along with several species of perennial grasses, groundsels, yarrow, cinquefoil, lupines, sedges, and asters, grow in this sub-alpine climate.^[20] Mountain lions, Kaibab squirrels, and northern goshawks are found here.^[21]

Montane meadows and subalpine grassland communities of the Hudsonian life zone are rare and located only on the North Rim.^[20] Both are typified by many grass species. Some of these grasses include blue and black grama, big galleta, Indian ricegrass and three-awns.^[20] The wettest areas support sedges and forbs.^[20]

Grand Canyon tourism

Grand Canyon National Park is one of the world’s premier natural attractions, attracting about five million visitors per year. Overall, 83% were from the United States: California (12.2%), Arizona (8.9%), Texas (4.8%), Florida (3.4%) and New York (3.2%) represented the top domestic visitors. Seventeen percent of visitors were from outside the United States; the most prominently represented nations were the United Kingdom (3.8%), Canada (3.5%), Japan (2.1%), Germany (1.9%) and The Netherlands (1.2%).^[31]

Activities

Further information: Grand Canyon travel guide from Wikitravel

A view of Grand Canyon Skywalk from Outside Ledge

Aside from casual sightseeing from the South Rim (averaging 7000 feet (2100 m) above sea level), whitewater rafting, hiking and running are especially popular. The floor of the valley is accessible by foot, muleback, or by boat or raft from upriver. Hiking down to the river and back up to the rim in one day is discouraged by park officials because of the distance, steep and rocky trails, change in elevation, and danger of heat exhaustion from the much higher temperatures at the bottom. Rescues are required annually of unsuccessful rim-to-river-to-rim travelers. Nevertheless, hundreds of fit and experienced hikers complete the trip every year.

Aerial view of the less-visited lower Grand Canyon, down river from (west of) Toroweap Overlook

Grand Canyon as seen from a commercial airplane

Camping on the North and South Rims is generally restricted to established campgrounds and reservations are highly recommended, especially at the busier South Rim. There is at large camping available along many parts of the North Rim managed by Kaibab National Forest. Keep in mind North Rim campsites are only open seasonally due to road closures from weather and winter snowpack. All overnight camping below the rim requires a backcountry permit from the Backcountry Country Office (BCO). Each year Grand Canyon National Park receives approximately 30,000 requests for backcountry permits. The park issues 13,000 permits, and close to 40,000 people camp overnight.^[32] The earliest a permit application is accepted is the first of the month, four months before the proposed start month. Applying as soon as allowed will improve your chances of obtaining an overnight backcountry use permit for the dates of your choice. If you are unable to secure a permit from the Grand Canyon Backcountry Office, or you are not comfortable hiking the Canyon on your own you can go with a professional guide.

The Coconino Canyon Train is another option for those seeking to take in a more leisurely view of the canyon. It is a 90-minute ride that originates in Grand Canyon National Park at the old Grand Canyon Depot and travels 24 miles through the canyon landscapes. The train is made up of 1923 Pullman cars and runs on tracks built in the 1800s.^[33]

Tourists wishing for a more vertical perspective can board helicopters and small airplanes in Las Vegas, Phoenix and Grand Canyon National Park Airport (seven miles from the South Rim) for canyon flyovers. Scenic flights are no longer allowed to fly within 1500' of the rim within the national park because of a late 90s crash. The last aerial video footage from below the rim was filmed in 1984. However, some helicopter flights land on the Havasupai and Hualapai Indian Reservations within Grand Canyon (outside of the park boundaries). Recently, the Hualapai Tribe opened the glass-bottomed Grand Canyon Skywalk on their property, Grand Canyon West. The Skywalk has seen mixed reviews since the site is only accessible by driving down a 14-mile (23 km) dirt road, costs a minimum of $85 in total for reservation fees, a tour package and admission to the Skywalk itself and the fact that cameras are not permitted on the Skywalk at any time. The Skywalk is some 240 miles west of Grand Canyon Village at the South Rim. Some people mistake the area of Hermit's Rest as the location of the Skywalk.^{[citation needed]}

Viewing the canyon

Home video: a flight over the Grand Canyon - with sound (approx. 6 Minutes)

Lipan Point is a promontory located on the South Rim. This point is located to the east of the Grand Canyon Village along the Desert View Drive. There is a parking lot for visitors who care to drive along with the Canyon's bus service that routinely stops at the point. The trailhead to the Tanner Trail is located just before the parking lot. The view from Lipan Point shows a wide array of rock strata and the Unkar Creek area in the inner canyon.

The canyon can be seen from the Toroweap (or Tuweep) Overlook situated 3000 vertical feet above the Colorado River, about 50 miles downriver from the South Rim and 70 upriver from the Grand Canyon Skywalk. This region — “One of the most remote in the United States” according to the National Park Service — is reached only by one of three lengthy dirt tracks, that start from St. George, Utah, Colorado City or near Pipe Spring National Monument (both in Arizona). These roads traverse wild, uninhabited land for 97, 62 and 64 miles respectively. The Park Service manages the area for its primitive values and, therefore, improvements and services are minimal.

Grand Canyon fatalities

This section does not cite any references or sources. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed. (August 2009)

This section may require cleanup to meet Wikipedia's quality standards. Please improve this section if you can. (August 2009)

Grand Canyon rescue Helicopter, 1978

About 600 deaths have occurred in the Grand Canyon since the 1870s. Some of these deaths occurred as the result of overly zealous photographic endeavors, some were the result of airplane collisions within the canyon, and some visitors drowned in the Colorado River. Many hikers overestimate their fitness level, become dehydrated and confused, and must be rescued. The Park Service now posts a picture of an attractive and fit young man at several trailheads with the caption "Every year we rescue hundreds of people from the Canyon. Most of them look like him", in an attempt to discourage hikers from feats which are beyond their abilities.

According to Over the Edge: Death in the Grand Canyon,^{[citation needed]} 53 fatalities have resulted from falls; 65 deaths were attributable to environmental causes, including heat stroke, cardiac arrest, dehydration, and hypothermia; 7 were caught in flash floods; 79 were drowned in the Colorado River; 242 perished in airplane and helicopter crashes (128 of them in the 1956 disaster mentioned below); 25 died in freak errors and accidents, including lightning strikes and rock falls; 48 committed suicide; and 23 were the victims of homicides.

1956 air disaster

Main article: 1956 Grand Canyon mid-air collision

In 1956 the Grand Canyon was the site of the deadliest commercial aviation disaster in history at the time.

On the morning of June 30, 1956, a TWA Lockheed Super Constellation and a United Airlines Douglas DC-7 departed Los Angeles International Airport within three minutes of one another on eastbound transcontinental flights. Approximately 90 minutes later, the two propeller-driven airliners collided above the canyon while both were flying in unmonitored airspace.

The wreckage of both planes fell into the eastern portion of the canyon, on Temple and Chuar Buttes, near the confluence of the Colorado and Little Colorado rivers. The disaster killed all 128 passengers and crew members aboard both planes.

This accident led to the institution of high-altitude flightways and positive control by en route ground controllers.

Evacuation

Canyon tourists and residents of Supai, a town located in the bottom of the canyon, were evacuated from the Supai area on and August 17-18, 2008^[34] due to a break in the earthen Redlands Dam, located upstream of Supai, after a night of heavy rainfall. Evacuees were taken to Peach Springs, Arizona.^[35] More heavy rains were expected and a flash flood warning was put into effect, necessitating the evacuation, according to the Grand Canyon National Park Service.^[36] The floods were significant enough to attract coverage from international media.^[35]

suci's blogger

Senin, 26 Oktober 2009