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Mauna Kea is a dormant volcano in the Hawaiian Islands, one of five volcanoes which together form the island of Hawaii. Pu'u Wekiu, one of numerous cinder cones on the summit plateau, is the highest point in the state of Hawaii at 13,796 feet (4,205 m). Mauna Kea is the tallest mountain in the world when measured from base to summit, since its base is located on the seafloor about 19,000 feet (5,800 m) beneath the surface of the Pacific Ocean, bringing its total height to about 33,000 ft (10,000 m). In the Hawaiian language, mauna kea means "white mountain", a reference to its summit being regularly snow-capped during the Northern Hemisphere winter.
[edit] Geology
The Island of Hawaiʻi is built from five separate shield volcanoes that erupted somewhat sequentially, one overlapping the other. These are (from oldest to youngest):
Mauna Kea is in the post-shield stage of volcanic evolution, having made the transition from the shield stage before about 200,000 to 250,000 years ago. At that time, its appearance was probably quite similar to that of its neighbor Mauna Loa today, a smooth shield volcano with a large summit caldera. Following the transition, eruptions became more explosive in character, resulting in the formation of numerous overlapping cinder cones which eventually filled and completely obscured the caldera. These cinder cones now form the peaks at the summit of Mauna Kea, with several of them exceeding 13,500 ft (4,100 m) in elevation. After several hundred thousand years of slowly building itself up by volcanic activity, the mountain's height is slowly decreasing now as its massive weight depresses the Pacific seafloor beneath it. The summit of Mauna Kea was entirely covered by a massive ice cap during the Pleistocene ice ages. The summit shows evidence of four periods of glaciation over the last 200,000 years, the last ending about 11,000 years ago, when the most recent ice age finished. The dense rock at the noted adz quarry near the summit is believed to have been formed when lava erupted under a glacier. Close to the top is Lake Waiau, the seventh highest lake in the USA [1] [edit] Climatic zones and biomes
The summit plateau of Mauna Kea is entirely above timberline, with a landscape of mostly bare rock with patches of alpine tundra. Snowfall often occurs at elevations above 11,000 feet (3,400 m) during the period from November through March. During particularly cold and wet winters (usually linked to La Niña), a snowpack several feet (1 m) deep may remain in the summit region above 13,000 ft (4,000 m) for weeks or months, permitting skiing and other snowplay activities on the slopes of the cinder cones. Between 5,200 and 8,000 feet (1,600 and 2,400 m) is a band of ranch land, which was formerly koa-mamane forest but has been almost entirely converted to pasture. This area has suffered from heavy infestations of gorse, an invasive species in Hawaii. Most of the north and west slopes are also pasture. The palila, an endangered finch-like honeycreeper, feeds almost exclusively on mamane seeds and lives in mamane-naio forest on the west slope. Large numbers of feral sheep inhabit the upper elevations, and have had a severe impact on the native vegetation. The windward (eastern) slopes are covered in rain forest between about 1,500 and 5,200 feet (450-1,600 m) elevation. Below this are extensive agricultural lands that formerly included vast areas of sugar cane. With the collapse of the sugar industry in the 1990s, much of this land is idle or used for eucalyptus farming for wood pulp, cattle grazing, or small-scale farming. [edit] Astronomy
The summit of Mauna Kea has been a celestial observatory since ancient times, and is considered to be one of the best astronomical sites in the world. For this reason it is home to many of the world's leading astronomical observatories. The summit is above approximately 40% of Earth's atmosphere and 90% of the water vapor, allowing for exceptionally clear images of the night sky. Additionally, the peak is well above the inversion layer, allowing up to 300 clear nights per year. Also, at 20°N latitude, much of both the northern and southern skies are visible. The fact that it is a shield volcano has meant that road transportation to the summit is relatively easy. The low population density of the Island of Hawaii means that there is little light pollution from man-made sources. All of these factors have made Mauna Kea an ideal location for state-of-the-art astronomy. Construction of telescopes on Mauna Kea has been a source of intense legal and political controversy in recent years. Due to the qualities listed above, it is a highly favored location and the summit area is now home to over a dozen telescopes. Native Hawaiian and environmental groups have protested that construction of additional telescopes would cause considerable environmental damage and further desecrate a site of great cultural importance. According to legend, the summit of Mauna Kea is the home of the snow goddess, Poliahu, and many other deities. It is also an important site for prayer, burials, consecration of children, and traditional celestial observation. In addition, the summit area is home to a unique insect, the wēkiu bug, which feeds on insects blown to the summit by updrafts; the insect itself is a major point of debate.[2] Large mercury spills and sewage dumps have also occurred at the existing telescopes; these are of particular concern because of the unique and otherwise-pristine underground water systems in the area.[3] Over the past decade, major legal battles have raged through Hawai'i's court system over these issues. Recently, the Third Circuit Court reaffirmed its decision to halt all further development on Mauna Kea until an appropriate Management Plan that sufficiently addresses the environmental damage and cultural impacts posed by astronomical development has been fully approved.[4] Despite the courts' rulings against further development, plans for additional telescopes have been moving forward. While some consider it highly illegal, the U.S. Air Force is attempting to build Pan-STARRS, a major telescope project.[5] Citing the extinction of the dinosaurs, a recent impact on Jupiter and science fiction films,[6] the telescope is promoted as protection against an asteroid impact. Opponents, however, believe the application to be military in nature.[5] Even more recently, the TMT (Thirty Meter Telescope) project -- the single largest telescope ever built on Earth -- is being currently proposed by Caltech, with funding and technology from Intel Corporation.[7] The telescope's developers propose to give scholarships for native Hawaiians as compensation for some of the cultural and environmental destruction that the project would entail.[8] Hearings for this project are scheduled throughout October 2008. [edit] Ski areasThere are limited ski areas on Mauna Kea, with no ski lifts or services provided. [edit] See also
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