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19-595: The Bewani Mountains form a mountain range in northwestern Papua New Guinea . Together with the Torricelli Mountains and Prince Alexander Mountains it forms the North Coastal Range of Papua New Guinea. The highest point of the mountains is at 1,960 m. The Bewani languages and various other Papuan languages are spoken in the region. The Bewani-Torricelli-Prince Alexander Mountains, are presumed to have been formed as an island arc in

38-627: A mix of different orogenic expressions and terranes , for example thrust sheets , uplifted blocks , fold mountains, and volcanic landforms resulting in a variety of rock types . Most geologically young mountain ranges on the Earth's land surface are associated with either the Pacific Ring of Fire or the Alpide belt . The Pacific Ring of Fire includes the Andes of South America, extends through

57-602: Is a major factor for meteorologists to consider when they forecast the local weather. Orography can play a major role in determining the type, amount, intensity, and duration of precipitation events. Researchers have discovered that barrier width, slope steepness, and updraft speed are major contributors when it comes to achieving the optimal amount and intensity of orographic precipitation. Computer models simulating these factors have shown that narrow barriers and steeper slopes produce stronger updraft speeds, which in turn increase orographic precipitation. Orographic precipitation

76-538: Is at work while the mountains are being uplifted until the mountains are reduced to low hills and plains. The early Cenozoic uplift of the Rocky Mountains of Colorado provides an example. As the uplift was occurring some 10,000 feet (3,000 m) of mostly Mesozoic sedimentary strata were removed by erosion over the core of the mountain range and spread as sand and clays across the Great Plains to

95-423: Is being lifted expands and cools adiabatically. This adiabatic cooling of a rising moist air parcel may lower its temperature to its dew point , thus allowing for condensation of the water vapor contained within it, and hence the formation of a cloud . If enough water vapor condenses into cloud droplets, these droplets may become large enough to fall to the ground as precipitation. Terrain-induced precipitation

114-663: Is known to occur on oceanic islands , such as the Hawaiian Islands and New Zealand ; much of the rainfall received on such islands is on the windward side, and the leeward side tends to be quite dry, almost desert -like. This phenomenon results in substantial local gradients in the amount of average rainfall, with coastal areas receiving on the order of 20 to 30 inches (510 to 760 mm) per year, and interior uplands receiving over 100 inches (2,500 mm) per year. Leeward coastal areas are especially dry—less than 20 in (510 mm) per year at Waikiki —and

133-486: Is the study of the topographic relief of mountains , and can more broadly include hills, and any part of a region's elevated terrain. Orography (also known as oreography , orology, or oreology ) falls within the broader discipline of geomorphology . The term orography comes from the Greek : όρος , hill, γράφω , to write. Mountain ranges and elevated land masses have a major impact on global climate. For instance,

152-520: Is thought to be endemic to the Bewani Mountains. Two frog species described in 2000/2001, Cophixalus bewaniensis and Choerophryne longirostris , are so far only known from the Bewani Mountains. Mountain range Mountain ranges are usually segmented by highlands or mountain passes and valleys . Individual mountains within the same mountain range do not necessarily have the same geologic structure or petrology . They may be

171-551: The Annamite Range . If the definition of a mountain range is stretched to include underwater mountains, then the Ocean Ridge forms the longest continuous mountain system on Earth, with a length of 65,000 kilometres (40,400 mi). The position of mountain ranges influences climate, such as rain or snow. When air masses move up and over mountains, the air cools, producing orographic precipitation (rain or snow). As

190-560: The Mithrim Montes and Doom Mons on Titan, and Tenzing Montes and Hillary Montes on Pluto. Some terrestrial planets other than Earth also exhibit rocky mountain ranges, such as Maxwell Montes on Venus taller than any on Earth and Tartarus Montes on Mars . Jupiter's moon Io has mountain ranges formed from tectonic processes including the Boösaule , Dorian, Hi'iaka and Euboea Montes . Orography Orography

209-848: The North American Cordillera , the Aleutian Range , on through Kamchatka Peninsula , Japan , Taiwan , the Philippines , Papua New Guinea , to New Zealand . The Andes is 7,000 kilometres (4,350 mi) long and is often considered the world's longest mountain system. The Alpide belt stretches 15,000 km across southern Eurasia , from Java in Maritime Southeast Asia to the Iberian Peninsula in Western Europe , including

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228-592: The Late Eocene -Early Oligocene . As with other mountain ranges in Papua New Guinea, the Bewani Mountains are home to many rare species of fauna and flora and is highly biodiverse . The black sicklebill ( Epimachus fastuosus ) is a threatened species which is known from a few localities in the Bewani and Torricelli mountains. Fiwo, a subspecies of the tenkile ( Dendrolagus scottae ) tree-kangaroo ,

247-627: The air descends on the leeward side, it warms again (following the adiabatic lapse rate ) and is drier, having been stripped of much of its moisture. Often, a rain shadow will affect the leeward side of a range. As a consequence, large mountain ranges, such as the Andes, compartmentalize continents into distinct climate regions . Mountain ranges are constantly subjected to erosional forces which work to tear them down. The basins adjacent to an eroding mountain range are then filled with sediments that are buried and turned into sedimentary rock . Erosion

266-485: The east. This mass of rock was removed as the range was actively undergoing uplift. The removal of such a mass from the core of the range most likely caused further uplift as the region adjusted isostatically in response to the removed weight. Rivers are traditionally believed to be the principal cause of mountain range erosion, by cutting into bedrock and transporting sediment. Computer simulation has shown that as mountain belts change from tectonically active to inactive,

285-472: The elevated areas of East Africa substantially determine the strength of the Indian monsoon . In scientific models, such as general circulation models , orography defines the lower boundary of the model over land. When a river's tributaries or settlements by the river are listed in 'orographic sequence', they are in order from the highest (nearest the source of the river) to the lowest or mainstem (nearest

304-476: The mouth). This method of listing tributaries is similar to the Strahler Stream Order , where the headwater tributaries are listed as category 1. Orographic precipitation, also known as relief precipitation, is precipitation generated by a forced upward movement of air upon encountering a physiographic upland (see anabatic wind ). This lifting can be caused by: Upon ascent, the air that

323-619: The ranges of the Himalayas , Karakoram , Hindu Kush , Alborz , Caucasus , and the Alps . The Himalayas contain the highest mountains in the world, including Mount Everest , which is 8,848 metres (29,029 ft) high. Mountain ranges outside these two systems include the Arctic Cordillera , Appalachians , Great Dividing Range , East Siberians , Altais , Scandinavians , Qinling , Western Ghats , Vindhyas , Byrrangas , and

342-627: The rate of erosion drops because there are fewer abrasive particles in the water and fewer landslides. Mountains on other planets and natural satellites of the Solar System, including the Moon , are often isolated and formed mainly by processes such as impacts, though there are examples of mountain ranges (or "Montes") somewhat similar to those on Earth. Saturn 's moon Titan and Pluto , in particular, exhibit large mountain ranges in chains composed mainly of ices rather than rock. Examples include

361-510: The tops of moderately high uplands are especially wet—about 475 in (12,100 mm) per year at Wai'ale'ale on Kaua'i . Another area in which orographic precipitation is known to occur is the Pennines in the north of England : the west side of the Pennines receives more rain than the east because the clouds are forced up and over the hills and cause the rain to tend to fall on

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