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28-769: The definition of continent is a matter of some dispute among mountaineers seeking to complete this challenge. The main ridge of the Greater Caucasus range is generally considered to form the boundary between Asia and Europe . In that case, Mount Elbrus (5,642 m (18,510 ft)) and Dykh-Tau (5,205 m (17,077 ft)), are the two highest mountains in Europe. Excluding the Caucasus Mountains , Mont Blanc (4,808 m (15,774 ft)) and Monte Rosa (4,634 m (15,203 ft)) would be Europe's two highest mountains. The Australian continent

56-675: A few inches tall, with weak root systems. Other common plant life-forms include prostrate shrubs ; tussock -forming graminoids ; cushion plants ; and cryptogams , such as bryophytes and lichens . Relative to lower elevation areas in the same region, alpine regions have a high rate of endemism and a high diversity of plant species. This taxonomic diversity can be attributed to geographical isolation , climate changes , glaciation , microhabitat differentiation, and different histories of migration or evolution or both. These phenomena contribute to plant diversity by introducing new flora and favoring adaptations , both of new species and

84-450: A few yards of each other, depending on topography, substrate, and climate. Alpine vegetation generally occurs in a mosaic of small patches with widely differing environmental conditions. Vegetation types vary from cushion and rosette plants on the ridges and in the rock crannies; to herbaceous and grassy vegetation along the slopes; dwarf shrubs with grasses and forbs below the melting snowdrifts; and sedges, grasses, low shrubs, and mosses in

112-633: A mountain is roughly equivalent to moving 80 kilometers (45 miles or 0.75° of latitude) towards the pole. This relationship is only approximate, however, since local factors such as proximity to oceans can drastically modify the climate. In the alpine tundra, trees cannot tolerate the environmental conditions (usually cold temperatures, extreme snowpack, or associated lack of available moisture). Typical high-elevation growing seasons range from 45 to 90 days, with average summer temperatures near 10 °C (50 °F). Growing season temperatures frequently fall below freezing, and frost occurs throughout

140-454: A relationship between the Arctic and Antarctic tree lines and the 10 °C summer isotherm; i.e., places where the average temperature in the warmest calendar month of the year is below 10 °C cannot support forests. See Köppen climate classification for more information. Otto Nordenskjöld theorized that winter conditions also play a role: His formula is W = 9 − 0.1 C , where W is

168-547: A role as well; the treeline often occurs at higher elevations on warmer equator-facing slopes. Because the alpine zone is present only on mountains, much of the landscape is rugged and broken, with rocky, snowcapped peaks, cliffs, and talus slopes, but also contains areas of gently rolling to almost flat topography. Averaging over many locations and local microclimates , the treeline rises 75 meters (245 ft) when moving 1 degree south from 70 to 50°N, and 130 meters (430 ft) per degree from 50 to 30°N. Between 30°N and 20°S,

196-500: Is defined as comprising the mainland of Australia and proximate islands on the same continental shelf , including Tasmania and New Guinea . In the convention of the seven continents , one of the continents is the region of Australasia , which includes for example the mountainous islands of New Zealand . For both the geological and conventional continent, New Guinea's Puncak Jaya / Carstensz Pyramid (4,884 m (16,024 ft)) and Puncak Mandala (4,758 m (15,610 ft)) are

224-456: Is observed. Alpine areas are unique because of the severity and complexity of their environmental conditions. Very small changes in topography – as small as 1 foot (0.3 m) or less – may mean the difference between a windswept area or an area of snow accumulation, changing the potential productivity and plant community drastically. Between these extremes of drought versus saturation , several intermediate environments may exist all within

252-539: Is the third-highest of the Australian continent . However, SRTM data do support Puncak Mandala being taller than Puncak Trikora. Heights of mountain peaks in West Papua are poorly established. Both lists consider the Caucasus Mountains as European. This makes Shkhara (5,193 m (17,037 ft)), located on the border between Georgia and Russia , the third-highest summit in Europe. Those who exclude

280-759: The Absheron Peninsula of the Caspian Sea : from the Western Caucasus in the vicinity of Sochi on the northeastern shore of the Black Sea and reaching nearly to Baku on the Caspian. The range is traditionally separated into three parts: In the wetter Western Caucasus, the mountains are heavily forested ( deciduous forest up to 1,500 metres (4,900 ft), coniferous forest up to 2,500 metres (8,200 ft) and alpine meadows above

308-629: The Caucasus Mountains from Europe, regard the Dom (4,545 m (14,911 ft)), located in Switzerland , as Europe's third-highest summit. Greater Caucasus The Greater Caucasus is the major mountain range of the Caucasus Mountains . It stretches for about 1,200 kilometres (750 mi) from west-northwest to east-southeast, from the Taman Peninsula of the Black Sea to

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336-1010: The North American Cordillera and parts of the northern Appalachian Mountains in North America, the Alps and Pyrenees of Europe, the Himalaya and Karakoram of Asia, the Andes of South America, the Eastern Rift mountains of Africa, the Snowy Mountains of Australia, the South Island of New Zealand, and the Scandinavian Mountains . Alpine tundra occupies high-mountain summits, slopes, and ridges above timberline. Aspect plays

364-502: The snow line where snow and ice persist through summer. Alpine tundra occurs in mountains worldwide. The flora of the alpine tundra is characterized by dwarf shrubs close to the ground. The cold climate of the alpine tundra is caused by adiabatic cooling of air, and is similar to polar climate . Alpine tundra occurs at high enough altitude at any latitude . Portions of montane grasslands and shrublands ecoregions worldwide include alpine tundra. Large regions of alpine tundra occur in

392-641: The tree line ). In the drier Eastern Caucasus, the mountains are mostly treeless. The watershed of the Caucasus is also considered by some to be the boundary between Eastern Europe and Western Asia . The European part to the north of the watershed is known as Ciscaucasia ; the Asiatic part to the south as Transcaucasia , which is dominated by the Lesser Caucasus mountain range and whose western portion converges with Eastern Anatolia . Most of

420-650: The Australian continent's highest summit. Reinhold Messner proposed another list (the Messner or Carstensz list) replacing Mount Kosciuszko with Western New Guinea's Puncak Jaya (4,884 m (16,024 ft)), which is part of Indonesia. Following the Bass list, Mount Twynam is the third-highest summit (2,196 m (7,205 ft)) in Australia . According to the Messner list, Puncak Trikora (4,750 m) on New Guinea

448-440: The average temperature in the warmest month and C the average of the coldest month, both in degrees Celsius (this would mean, for example, that if a particular location had an average temperature of −20 °C (−4 °F) in its coldest month, the warmest month would need to average 11 °C (52 °F) or higher for trees to be able to survive there). In 1947, Holdridge improved on these schemes, by defining biotemperature :

476-514: The bogs and along the brooks. Alpine meadows form where sediments from the weathering of rocks has produced soils well-developed enough to support grasses and sedges. Non-flowering lichens cling to rocks and soil. Their enclosed algal cells can photosynthesize at any temperature above 0 °C (32 °F), and the outer fungal layers can absorb more than their own weight in water. The adaptations for survival of drying winds and cold may make tundra vegetation seem very hardy, but in some respects

504-589: The border of Russia with Georgia and Azerbaijan runs along most of the Caucasus' length. The Georgian Military Road ( Darial Gorge ) and Trans-Caucasus Highway traverse this mountain range at altitudes of up to 3,000 metres (9,800 ft). The watershed of the Caucasus was the border between the Caucasia province of the Russian Empire in the north and the Ottoman Empire and Persia in

532-456: The dispersal of pre-existing species. Though tundra covers only a minority of the Earth's surface (17-20%), the biodiversity of plant species is important to human nutrition. Of the 20 plant species that make up 80% of human food, 7 of them (35%) originated in this region. Plants have adapted to the harsh alpine environment. Cushion plants , looking like ground-hugging clumps of moss, escape

560-488: The ground and consists mainly of perennial grasses , sedges , and forbs . Perennial herbs (including grasses, sedges, and low woody or semi-woody shrubs) dominate the alpine landscape; they have much more root and rhizome biomass than that of shoots, leaves, and flowers. The roots and rhizomes not only function in water and nutrient absorption but also play a very important role in over-winter carbohydrate storage. Annual plants are rare in this ecosystem and usually are only

588-771: The growing season in many areas. Precipitation occurs mainly as winter snow, but soil water availability is highly variable with season, location, and topography. For example, snowfields commonly accumulate on the lee sides of ridges while ridgelines may remain nearly snow free due to redistribution by wind. Some alpine habitats may be up to 70% snow free in winter. High winds are common in alpine ecosystems, and can cause significant soil erosion and be physically and physiologically detrimental to plants. Also, wind coupled with high solar radiation can promote extremely high rates of evaporation and transpiration . There have been several attempts at quantifying what constitutes an alpine climate. Climatologist Wladimir Köppen demonstrated

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616-470: The latitude of a location approaches the poles, the threshold elevation for alpine tundra gets lower until it reaches sea level, and alpine tundra merges with polar tundra . The high elevation causes an adverse climate, which is too cold and windy to support tree growth. Alpine tundra transitions to sub-alpine forests below the tree line ; stunted forests occurring at the forest-tundra ecotone are known as krummholz . With increasing elevation it ends at

644-400: The mean annual temperature, where all temperatures below 0 °C are treated as 0 °C (because it makes no difference to plant life, being dormant). If the mean biotemperature is between 1.5 and 3 °C (34.7 and 37.4 °F), Holdridge quantifies the climate as alpine. Since the habitat of alpine vegetation is subject to intense radiation, wind, cold, snow, and ice, it grows close to

672-666: The south (1801) until the Russian victory in 1813 and the Treaty of Gulistan which moved the border of the Russian Empire well within Transcaucasia. The border between Georgia and Russia still follows the watershed almost exactly (except for Georgia's western border, which extends south of the watershed, and a narrow strip of territory in northwestern Kakheti and northern Mtskheta-Mtianeti where Georgia extends north of

700-468: The strong winds blowing a few inches above them. Many flowering plants of the alpine tundra have dense hairs on stems and leaves to provide wind protection or red-colored pigments capable of converting the sun's light rays into heat. Some plants take two or more years to form flower buds, which survive the winter below the surface and then open and produce fruit with seeds in the few weeks of summer. In various areas of alpine tundra, woody plant encroachment

728-506: The treeline is roughly constant, between 3,500 and 4,000 meters (11,500 and 13,100 ft). Alpine climate is the average weather ( climate ) for the alpine tundra. The climate becomes colder when reaching higher elevations —this characteristic is described by the lapse rate of air: air tends to get colder as it rises, since it expands. The dry adiabatic lapse rate is 10 °C per km (5.5 °F per 1000 ft) of elevation or altitude. Therefore, moving up 100 meters (330 ft) on

756-551: The two highest summits. When considering a continent as a continuous landmass surrounded by oceans, mainland Australia would be its own continent, with Mount Kosciuszko (2,228 m (7,310 ft)) and Mount Townsend (2,209 m (7,247 ft)) as its two highest summits. The Third Seven Summits list follows the Seven Summits list created by Richard Bass , who chose the highest mountain of mainland Australia, Mount Kosciuszko (2,228 m (7,310 ft)), to represent

784-403: The watershed), while Azerbaijan is south of the watershed except that its northeastern corner has five districts north of the watershed ( Khachmaz , Quba , Qusar , Shabran , and Siazan ). Download coordinates as: Alpine meadow Alpine tundra is a type of natural region or biome that does not contain trees because it is at high elevation , with an associated harsh climate . As

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