Реферат на тему:
Natural wonders
Similar to the other lists of wonders, there is no consensus on a list of seven natural wonders of the world, as there has been debate over how large the list should be. One of the many lists was compiled by CNN:
· Grand Canyon
· Great Barrier Reef
· Harbor of Rio de Janeiro
· Mount Everest
· Polar Aurora
· Parícutin volcano
· Victoria Falls
The Grand Canyon
is a very colorful, steep-sided gorge, carved by the Colorado River, in the U.S. state of Arizona. It is largely contained within the Grand Canyon National Park — one of the first national parks in the United States. President Theodore Roosevelt was a major proponent of the Grand Canyon area, visiting on numerous occasions to hunt and enjoy the scenery.
The canyon, created by the Colorado River cutting a channel over millions of years, is about 277 miles (446 km) long, ranges in width from 0.25 to 15 miles (0.4 to 24 kilometers), and attains a depth of more than a mile (1 km). Nearly two billion years of the Earth's history has been exposed as the Colorado River and its tributaries cut through layer after layer of sediment as the Colorado Plateaus have uplifted.
The first recorded sighting of the Grand Canyon by a European was in 1540, García López de Cárdenas from Spain. Grand Canyon was largely unknown until after the U.S. Civil War. In 1869, Major John Wesley Powell, a one-armed Civil War veteran with a thirst for science and adventure, made a pioneering journey through the canyon on the Colorado River. He accomplished this with nine men in four small wooden boats, though only six men completed the journey. His party was, as far as we know, the first ever to make such a trip. Powell referred to the sedimentary rock units exposed in the canyon as "leaves in a great story book". Long before that, the area was inhabited by Native Americans who built settlements within the canyon walls and its many caves.
The Great Barrier Reef
is the world's largest coral reef system, composed of roughly 3,000 individual reefs and 900 islands that stretch for 2,600 kilometres (1,616 mi) and cover an area of approximately 344,400 km². The reef is located in the Coral Sea, off the coast of Queensland in northeast Australia. A large part of the reef is protected by the Great Barrier Reef Marine Park.
The Great Barrier Reef can be seen from outer space and is sometimes referred to as the single largest organism in the world. In reality, it is made up of many millions of tiny organisms, known as coral polyps. The Great Barrier Reef supports a wide diversity of life and was selected as a World Heritage Site in 1981.CNN has labelled it one of the seven natural wonders of the world. The Queensland National Trust has named it a state icon of Queensland.
The Great Barrier Reef's environmental pressures include water quality from runoff, climate change and mass coral bleaching, cyclic outbreaks of the crown-of-thorns starfish, overfishing, and shipping accidents.
Rio de Janeiro
(IPA: Portuguese: "River of January"; is the name of both a state and a city in southeastern Brazil. The city was the capital of Brazil (1763–1960) and of the Portuguese Empire (1808–1821). Commonly known as just Rio, the city is also nicknamed A Cidade Maravilhosa - "The Marvelous City".
It is famous for its spectacular natural setting, its Carnival celebrations, samba and other music, hotel-lined tourist beaches, such as Copacabana, Ipanema, and Leblon and pavements decorated with black and cream swirl pattern mosaics. Some of the most famous local landmarks in addition to the beaches include the giant statue of Jesus, known as Christ the Redeemer ('Cristo Redentor') atop Corcovado mountain; Sugarloaf mountain (Pão de Açúcar) with its cable car; the Sambódromo, a giant permanent parade stand used during Carnival; and Maracanã stadium, the world's largest. Rio also boasts the world's largest forest inside an urban area, called Floresta da Tijuca, or 'Tijuca Forest'.
Rio de Janeiro
is located at 22 degrees, 54 minutes south latitude, 43 degrees 14 minutes west longitude (22°54′S 43°14′W). The population of the City of Rio de Janeiro is about 6,094,183 (2005 IBGE estimate), occupying an area of 1,182.3 square kilometres (456.5 sq mi). The larger metropolitan area population is estimated at 11-12 million. It is Brazil's second-largest city after São Paulo and was the country's capital until 1960, when Brasília took its place. Residents of the city are known as Cariocas. The city's current mayor (2006) is Cesar Maia. The official song of Rio
Mount Everest or Qomolangma or Sagarmatha
or Chomolungma pronounced as
(Jongmalunga) is the highest mountain on Earth, as measured by the height of its summit above sea level. The mountain, which is part of the Himalaya range in High Asia, is located on the border between Nepal and China.
The aurora
(plural aurorae/auroras) is a bright glow observed in the night sky, usually in the polar zone. For this reason some scientists call it a "polar aurora" (or "aurora polaris"). In northern latitudes, it is known as the aurora borealis which is named after the Roman goddess of the dawn, Aurora, and the Greek name for north wind, Boreas. Especially in Europe, it often appears as a reddish glow on the northern horizon, as if the sun were rising from an unusual direction. The aurora borealis is also called the northern lights since it is only visible in the North sky from the Northern Hemisphere. The aurora borealis most often occurs from September to October and from March to April. Its southern counterpart, aurora australis, has similar properties. Australis is the Latin word for "of the South".
Parícutin
(or Volcán de Parícutin, commonly also accented Paricutín) is a volcano in the Mexican state of Michoacán, close to a lava-covered village of the same name. It appears on many versions of the Seven Natural Wonders of the World list.
It began as a fissure in a cornfield owned by Tarascan american farmer Dionisio Pulido on February 20, 1943. Pulido, his wife, and son, all witnessed the initial eruption of ash and stones first-hand as they plowed the field. Much of the volcano's growth occurred during its first year, while it was still in the explosive pyroclastic phase. Nearby villages Paricutín (after which the volcano was named) and San Juan Parangaricutiro were both buried in lava and ash; the residents relocated to vacant land nearby. No one died from the Parícutin volcano.
At the end of this phase after roughly one year the volcano had grown 336 metres tall. For the next eight years the volcano would continue erupting, although this was dominated by relatively quiet eruptions of lava that would scorch the surrounding 25 km² of land. The volcano's activity would slowly decline during this period until the last six months of the eruption, during which violent and explosive activity was frequent. In 1952 the eruption ended and Parícutin went quiet, attaining a final height of 424 metres above the cornfield from which it was born. The volcano has been quiet since. Like most cinder cones, Parícutin is a monogenetic volcano, which means that it will never erupt again.
Volcanism is a common part of the Mexican landscape. Paricutín is merely the youngest of more than 1,400 volcanic vents that exist in the Trans-Mexican volcanic belt. The volcano is unique in the fact that its formation was witnessed from its very conception. Amazingly not one recorded death was caused by the eruption, although three people died as a result of lightning strikes caused by the eruptions.
Africa's Victoria Falls
or Mosi-oa-Tunya are, by some measures, the largest waterfall on the planet, as well as being among the most unusual in form, and having arguably the most diverse and easily-seen wildlife of any major waterfall site.
Although being neither the highest nor widest waterfalls in the world, the claim for being largest is based on a width of 1.7 km (1 mile) and a height of 108 m (360 ft), forming what may be the largest sheet of falling water in the world. No waterfalls are both wider and higher. Their maximum flow rate compares well with other major waterfalls (see table below).
The unusual form of Victoria Falls enables virtually the whole width of the falls to be viewed face-on, at the same level as the top, from a distance as close as 60 m (200 ft), because the whole Zambezi River drops into a deep, narrow slot-like chasm, connected to a long series of gorges. Few other waterfalls allow such a close approach on foot to the heart of their power.
Many of Africa's animals and birds can be seen in the immediate vicinity of Victoria Falls, and the continent's range of river fish are well represented in the Zambezi, enabling wildlife viewing and sports fishing to be combined with sightseeing.
Victoria Falls are one of Africa's major tourist attractions, and a UNESCO World Heritage Site (see box below). They are shared between Zambia and Zimbabwe, and each country has a national park to protect them and a town serving as a tourism centre: Mosi-oa-Tunya National Park and Livingstone in Zambia, and Victoria Falls National Park and the town of Victoria Falls in Zimbabwe.