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19-747: The plateaus rise behind a narrow coastal plain. They receive considerable orographic precipitation , making the plateaus cooler and wetter than the surrounding lowlands. The average annual rainfall is 1088 mm (1951-1979), recorded at the Rondo Forest station. The highest rainfall occurs between November and January, and March to May. It is an important stand of primary coastal forest in Tanzania, but also contains elements of montane forest, as it reaches 900 metres in altitude. The higher slopes are covered in extensive semi-deciduous hardwood forest, constituting over 18 square km of closed canopy forest. The plateau vegetation

38-416: 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 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

57-478: Is diverse, with areas of scrub forest, dry evergreen forest, riverine forest, miombo ( Brachystegia ) woodland, and thicket. Some 100 species of plant are endemic to the area. The plateau was once covered by extensive forests of Mvule or African teak ( Milicia excelsa ), but the forests were heavily logged from the 1950s onwards. Logging stopped in the 1980s, and since then the forests have regrown, and some areas were planted with Milicia excelsa . Milicia excelsa

76-428: Is home to various species of monkey and small mammals. The Rondo dwarf galago was discovered here in the 1990s by Simon Bearder. Though a forest reserve since colonial times, much wood was harvested in the 1950s, when some 20 square km of forest was cleared to establish exotic plantations, chiefly pine. The Rondo Nature Forest Reserve covers an area 11,742.26 ha, with a boundary of 51.6 km. Other forest reserves in

95-461: 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

114-476: Is still one of the dominant species in the 25 m high canopy within the Rondo Forest Reserve. Other dominant canopy species are Albizia gummifera , Dombeya sp., Ricinodendron heudelotii , and Dialium holtzii . The forest reserve also has areas of forest plantation , mostly Pinus sp. with small trial plots of Milicia excelsa , Teak ( Tectona grandis ) and Maesopsis eminii . The plateau

133-466: Is the lay of the land. This is usually expressed in terms of the elevation , slope , and orientation of terrain features. Terrain affects surface water flow and distribution. Over a large area, it can affect weather and climate patterns. Bathymetry is the study of underwater relief, while hypsometry studies terrain relative to sea level . The understanding of terrain is critical for many reasons: Relief (or local relief ) refers specifically to

152-509: 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, 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

171-531: 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 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

190-419: The full range of their interactions is still a topic of debate. Land surface parameters are quantitative measures of various morphometric properties of a surface. The most common examples are used to derive slope or aspect of a terrain or curvatures at each location. These measures can also be used to derive hydrological parameters that reflect flow/erosion processes. Climatic parameters are based on

209-504: 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 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,

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228-506: The modelling of solar radiation or air flow. Land surface objects, or landforms , are definite physical objects (lines, points, areas) that differ from the surrounding objects. The most typical examples airlines of watersheds , stream patterns, ridges , break-lines , pools or borders of specific landforms. A digital elevation model (DEM) or digital surface model (DSM) is a 3D computer graphics representation of elevation data to represent terrain or overlaying objects, commonly of

247-458: 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 is known to occur on oceanic islands , such as the Hawaiian Islands and New Zealand ; much of the rainfall received on such islands

266-480: The plateau region are Chitoa (770 ha), Litipo (1000 ha), Makangala (1271 ha), Ndimba (2687 ha), and Ruawa (2949 ha). The Noto Plateau is home to 12,000 ha of dry evergreen forest which has no protected status. Orographic precipitation Orography 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

285-410: The quantitative measurement of vertical elevation change in a landscape . It is the difference between maximum and minimum elevations within a given area, usually of limited extent. A relief can be described qualitatively, such as a " low relief " or " high relief " plain or upland . The relief of a landscape can change with the size of the area over which it is measured, making the definition of

304-472: The scale over which it is measured very important. Because it is related to the slope of surfaces within the area of interest and to the gradient of any streams present, the relief of a landscape is a useful metric in the study of the Earth's surface. Relief energy, which may be defined inter alia as "the maximum height range in a regular grid", is essentially an indication of the ruggedness or relative height of

323-544: The terrain. Geomorphology is in large part the study of the formation of terrain or topography. Terrain is formed by concurrent processes operating on the underlying geological structures over geological time : Tectonic processes such as orogenies and uplifts cause land to be elevated, whereas erosional and weathering processes wear the land away by smoothing and reducing topographic features. The relationship of erosion and tectonics rarely (if ever) reaches equilibrium. These processes are also codependent, however

342-500: 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

361-456: The western slopes. This is particularly noticeable between Manchester (to the west) and Leeds (to the east); Leeds receives less rain due to a rain shadow of 12 miles (19 km) from the Pennines. Terrain Terrain (from Latin : terra 'earth'), alternatively relief or topographical relief , is the dimension and shape of a given surface of land . In physical geography , terrain

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