HOME

TheInfoList




Terrain or relief (also
topographical Topography is the study of the forms and features of land surface Relief map of Sierra Nevada, Spain Terrain or relief (also topographical Topography is the study of the forms and features of land surfaces. The topography of an ...
relief) involves the vertical and horizontal dimensions of
land Land is the solid surface of Earth that is not permanently submerged in water. Most but not all land is situated at elevations above sea level (variable over geologic time frames) and consists mainly of Earth's crust, crustal components such a ...

land
surface. The term
bathymetry Bathymetry (pronounced ) is the study of underwater depth of ocean floor The ocean (also the sea or the world ocean) is the body of salt water which covers approximately 71% of the surface of the Earth.
bathymetry
is used to describe
underwater The underwater environment refers to the region below the surface of, and immersed in, liquid water Water is an Inorganic compound, inorganic, Transparency and translucency, transparent, tasteless, odorless, and Color of water, nearly ...

underwater
relief, while
hypsometry Hypsometry (from Greek ὕψος, ''hupsos'', "height" and μέτρον, ''metron'', "measure") is the measurement of land elevation The elevation of a geographic location (geography), location is its height above or below a fixed reference po ...
studies terrain relative to
sea level Mean sea level (MSL) (often shortened to sea level) is an average In colloquial, ordinary language, an average is a single number taken as representative of a list of numbers, usually the sum of the numbers divided by how many numbers are in th ...

sea level
. The Latin word ''terra'' (the root of ''terrain'') means "earth." In
physical geography Physical geography (also known as physiography) is one of the two fields of geography Geography (from Greek Greek may refer to: Greece Anything of, from, or related to Greece Greece ( el, Ελλάδα, , ), officially the Hell ...
, terrain is the lay of the land. This is usually expressed in terms of the
elevation The elevation of a geographic Geography (from Ancient Greek, Greek: , ''geographia'', literally "earth description") is a field of science devoted to the study of the lands, features, inhabitants, and phenomena of the Earth and Solar Sy ...

elevation
,
slope In mathematics, the slope or gradient of a line Line, lines, The Line, or LINE may refer to: Arts, entertainment, and media Films * ''Lines'' (film), a 2016 Greek film * ''The Line'' (2017 film) * ''The Line'' (2009 film) * ''The Line'', ...

slope
, and orientation of terrain features. Terrain affects surface water flow and distribution. Over a large area, it can affect
weather Weather is the state of the atmosphere An atmosphere (from the greek words ἀτμός ''(atmos)'', meaning 'vapour', and σφαῖρα ''(sphaira)'', meaning 'ball' or 'sphere') is a layer or a set of layers of gases surrounding a p ...

weather
and
climate Climate is the long-term pattern of weather Weather is the state of the atmosphere An atmosphere (from the greek words ἀτμός ''(atmos)'', meaning 'vapour', and σφαῖρα ''(sphaira)'', meaning 'ball' or 'sphere') is a la ...

climate
patterns.


Importance

The understanding of terrain is critical for many reasons: * The terrain of a region largely determines its suitability for human settlement: flatter alluvial plains tend to have better farming soils than steeper, rockier uplands. * In terms of
environmental quality"Environmental Quality" is a set of properties and characteristics of the environment, either generalized or local, as they impinge on human beings and other organisms. It is a measure of the condition of an environment relative to the requirements o ...
,
agriculture Agriculture is the science, art and practice of cultivating plants and livestock. Agriculture was the key development in the rise of sedentary Image:Family watching television 1958.jpg, Exercise trends, Increases in sedentary behaviors su ...

agriculture
,
hydrology Hydrology (from Ancient Greek, Greek wikt:ὕδωρ, ὕδωρ, ''hýdōr'' meaning "water" and wikt:λόγος, λόγος, ''lógos'' meaning "study") is the scientific study of the movement, distribution, and management of water on Earth and ...
and other interdisciplinary sciences;Baker, N.T., and Capel, P.D., 2011, "Environmental factors that influence the location of crop agriculture in the conterminous United States": U.S. Geological Survey Scientific Investigations Report 2011–5108, 72 p. understanding the terrain of an area assists the understanding of watershed boundaries,
drainage characteristics
drainage characteristics
, drainage systems, groundwater systems,
water movement
water movement
, and impacts on
water quality Water quality refers to the chemical A chemical substance is a form of matter In classical physics and general chemistry, matter is any substance that has mass and takes up space by having volume. All everyday objects that can be touche ...
. Complex arrays of relief data are used as input parameters for
hydrology transport model An hydrological transport model is a mathematical model A mathematical model is a description of a system A system is a group of Interaction, interacting or interrelated elements that act according to a set of rules to form a unified who ...
s (such as the
SWMM The United States Environmental Protection Agency (EPA) Storm Water Management Model (SWMM) is a dynamic rainfall–surface runoff, runoff–groundwater, subsurface runoff Scientific modelling, simulation model used for single-event to long-term (c ...
or
DSSAM Model The DSSAM Model (Dynamic Stream Simulation and Assessment Model) is a computer simulation Computer simulation is the process of mathematical modelling, performed on a computer, which is designed to predict the behaviour of or the outcome of a ...
s) to allow prediction of river
water quality Water quality refers to the chemical A chemical substance is a form of matter In classical physics and general chemistry, matter is any substance that has mass and takes up space by having volume. All everyday objects that can be touche ...

water quality
. * Understanding terrain also supports
soil conservation Soil conservation is the prevention of loss of the top most layer of the soil from erosion In earth science Earth science or geoscience includes all fields of natural science Natural science is a branch of science Science (from ...
, especially in agriculture.
Contour ploughing Contour bunding or contour farming or Contour ploughing is the farming practice of plowing and/or planting across a slope following its elevation contour lines. These contour lines create a water break which reduces the formation of rills and ...
is an established practice enabling
sustainable agriculture Sustainable agriculture is farming Agriculture is the science, art and practice of cultivating plants and livestock. Agriculture was the key development in the rise of sedentary Image:Family watching television 1958.jpg, Exercise tren ...

sustainable agriculture
on sloping land; it is the practice of ploughing along lines of equal elevation instead of up and down a slope. * Terrain is
militarily A military, also known collectively as armed forces, is a heavily armed, highly organized force primarily intended for warfare. It is typically officially authorized and maintained by a sovereign state, with its members identifiable by their ...

militarily
critical because it determines the ability of
armed forces A military, also known collectively as armed forces, is a heavily armed, highly organized force primarily intended for warfare War is an intense armed conflict between State (polity), states, governments, Society, societies, or pa ...
to take and hold areas, and move
troop A troop is a military sub-subunit Sub-subunit or sub-sub-unit is a subordinated element below platoon level of company-sized units or sub-units which normally might not be separately identified in authorization documents by name, number, o ...
s and material into and through areas. An understanding of terrain is basic to both defensive and offensive strategy. The military usage of "terrain" is very broad, encompassing not only landform but land use and land cover, surface transport infrastructure, built structures and
human geography Human geography or anthropogeography is the branch of geography Geography (from Greek Greek may refer to: Greece Anything of, from, or related to Greece Greece ( el, Ελλάδα, , ), officially the Hellenic Republic, is a coun ...
, and, by extension under the term
human terrain
human terrain
, even psychological, cultural, or economic factors. * Terrain is important in determining
weather Weather is the state of the atmosphere An atmosphere (from the greek words ἀτμός ''(atmos)'', meaning 'vapour', and σφαῖρα ''(sphaira)'', meaning 'ball' or 'sphere') is a layer or a set of layers of gases surrounding a p ...

weather
patterns. Two areas geographically close to each other may differ radically in
precipitation In meteorology Meteorology is a branch of the (which include and ), with a major focus on . The study of meteorology dates back , though significant progress in meteorology did not begin until the 18th century. The 19th century saw mod ...
levels or timing because of elevation differences or a "
rain shadow A rain shadow is an area of significantly reduced rainfall behind a mountainous region, on the side facing away from prevailing winds, known as its Windward and leeward#Meteorological significance, leeward side. Evaporation, Evaporated moistu ...

rain shadow
" effect. * Precise knowledge of terrain is vital in
aviation Aviation is the activities surrounding mechanical flight and the aircraft industry. ''Aircraft'' includes airplane, fixed-wing and helicopter, rotary-wing types, morphable wings, wing-less lifting bodies, as well as aerostat, lighter-than-air ...
, especially for low-flying routes and maneuvers ( see terrain collision avoidance) and airport altitudes. Terrain will also affect range and performance of radars and terrestrial
radio navigation Radio navigation or radionavigation is the application of radio Radio is the technology of signaling and telecommunication, communicating using radio waves. Radio waves are electromagnetic waves of frequency between 30 hertz (Hz) and ...
systems. Furthermore, a hilly or mountainous terrain can strongly impact the implementation of a new
aerodrome An aerodrome (Commonwealth English The use of the English language English is a West Germanic languages, West Germanic language first spoken in History of Anglo-Saxon England, early medieval England, which has eventually become th ...

aerodrome
and the orientation of its runways.


Relief

Relief (or ''local relief'') refers specifically to 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 "" or ""
plain In geography, a plain is a flat expanse of land that generally does not change much in elevation, and is primarily treeless. Plains occur as lowlands along valleys or at the base of mountains, as coastal plains, and as plateaus or Highland, up ...

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 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 In vector calculus Vector calculus, or vector analysis, is concerned with differentiation Differentiation may refer to: Business * Differentiation (economics), the process of making a product different from other similar products * Prod ...
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 the terrain.


Geomorphology

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 The geologic time scale (GTS) is a system of chronological datingChronological dating, or simply dating, is the process of attributing to an object or event a date in the past, allowing such object or event to be located in a previously establish ...

geological time
: *
Geological Geology (from the Ancient Greek γῆ, ''gē'' ("earth") and -λoγία, ''-logia'', ("study of", "discourse")) is an Earth science concerned with the solid Earth, the rock (geology), rocks of which it is composed, and the processes by which th ...

Geological
processes A process is a series or set of Action (philosophy), activities that interact to produce a result; it may occur once-only or be recurrent or periodic. Things called a process include: Business and management *Business process, activities that pro ...
: Migration of
tectonic plate This is a list of tectonic plates on Earth's surface Earth is the third planet A planet is an astronomical body orbiting a star or Stellar evolution#Stellar remnants, stellar remnant that is massive enough to be Hydrostatic equilibri ...
s,
faulting In geology Geology (from the Ancient Greek γῆ, ''gē'' ("earth") and -λoγία, ''-logia'', ("study of", "discourse")) is an Earth science concerned with the solid Earth, the rock (geology), rocks of which it is composed, and the proces ...
and folding,
mountain formation Mountain formation refers to the geological processes that underlie the formation of mountains. These processes are associated with large-scale movements of the Earth's crust (List of tectonic plates, tectonic plates). Fold (geology), Folding, ...
,
volcanic A volcano is a rupture in the crust of a planetary-mass object A planet is an astronomical body orbit In physics, an orbit is the gravitationally curved trajectory of an physical body, object, such as the trajectory of a planet ar ...

volcanic
eruptions, etc. *
Erosion In earth science Earth science or geoscience includes all fields of natural science Natural science is a branch of science Science (from the Latin word ''scientia'', meaning "knowledge") is a systematic enterprise that Scientific ...

Erosion
al
processes A process is a series or set of Action (philosophy), activities that interact to produce a result; it may occur once-only or be recurrent or periodic. Things called a process include: Business and management *Business process, activities that pro ...
:
glacial A glacial period (alternatively glacial or glaciation) is an interval of time (thousands of years) within an ice age An ice age is a long period of reduction in the temperature of Earth Earth is the third planet from the Sun and the ...
,
water Water (chemical formula H2O) is an Inorganic compound, inorganic, transparent, tasteless, odorless, and Color of water, nearly colorless chemical substance, which is the main constituent of Earth's hydrosphere and the fluids of all known li ...
,
wind Wind is the natural movement of air or other gases relative to a planet's surface. Wind occurs on a range of scales, from thunderstorm A thunderstorm, also known as an electrical storm or a lightning storm, is a storm characterized by th ...

wind
,
chemical A chemical substance is a form of matter In classical physics and general chemistry, matter is any substance that has mass and takes up space by having volume. All everyday objects that can be touched are ultimately composed of atoms, which ...
and gravitational (
mass movement A mass movement denotes a political party or movement which is supported by large segments of a population. Political movements that typically advocate the creation of a mass movement include the ideologies of communism Communism (from L ...
); such as
landslide Landslides, also known as landslips, are several forms of mass wasting Mass wasting, also known as mass movement, is a general term for the movement of rock Rock most often refers to: * Rock (geology) A rock is any naturally occurri ...

landslide
s,
downhill creep Downhill creep, also known as soil creep or commonly just creep, is the slow, downward progression of rock and soil Soil (often stylized as SOiL) is an American rock band that was formed in Chicago (''City in a Garden''); I Will , image ...
,
flows
flows
, slumps, and
rock falls
rock falls
. *
Extraterrestrial Extraterrestrial refers to any object or being beyond (wikt:extra-, extra-) the planet Earth (wikt:terrestrial, terrestrial). It is derived from the Latin words wikt:extra, ''extra'' ("outside", "outwards") and ''terrestris'' ("earthly", "of or rela ...

Extraterrestrial
:
meteorite A meteorite is a solid piece of debris from an object, such as a comet A comet is an icy, small Solar System body A small Solar System body (SSSB) is an object in the Solar System The Solar SystemCapitalization of the name varie ...
impacts
impacts
.
Tectonic Tectonics (; ) are the processes that control the structure and properties of the Earth's crust and its evolution through time. These include the processes of mountain building A mountain is an elevated portion of the Earth's crust, gen ...
processes such as
orogenies An orogeny is an event that leads to both structural Deformation (physics), deformation and compositional differentiation of the Earth's lithosphere (Crust (geology), crust and uppermost Mantle (geology), mantle) at Convergent boundary, converge ...
and uplifts cause land to be elevated, whereas erosional and
weathering Weathering is the deterioration of Rock (geology), rocks, soils and minerals as well as wood and artificial materials through contact with water, atmospheric gases, and biological organisms. Weathering occurs ''in situ'' (on site, with little o ...
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 the full range of their interactions is still a topic of debate.King, G., Herman, F., & Guralnik, B. (2016). Northward migration of the eastern himalayan syntaxis revealed by OSL thermochronometry. Science, 353(6301), 800-804. Land surface parameters are quantitative measures of various
morphometric Morphometrics (from Greek Greek may refer to: Greece Anything of, from, or related to Greece Greece ( el, Ελλάδα, , ), officially the Hellenic Republic, is a country located in Southeast Europe. Its population is approximately 10.7 mi ...
properties of a surface. The most common examples are used to derive
slope In mathematics, the slope or gradient of a line Line, lines, The Line, or LINE may refer to: Arts, entertainment, and media Films * ''Lines'' (film), a 2016 Greek film * ''The Line'' (2017 film) * ''The Line'' (2009 film) * ''The Line'', ...

slope
or
aspect Aspect or Aspects may refer to: Entertainment * ''Aspect magazine ASPECT Volume 9: Performance ''ASPECT'' was a biannual DVD The DVD (common abbreviation for Digital Video Disc or Digital Versatile Disc) is a digital optical disc data stor ...
of a terrain or curvatures at each location. These measures can also be used to derive hydrological parameters that reflect flow/erosion processes.
Climatic Climate is the long-term average of weather, typically averaged over a period of 30 years. More rigorously, it is the mean and variability of meteorological variables over a time spanning from months to millions of years. Some of the Meteorology, ...

Climatic
parameters are based on the modelling of
solar radiation Solar irradiance is the power Power typically refers to: * Power (physics) In physics, power is the amount of energy transferred or converted per unit time. In the International System of Units, the unit of power is the watt, equal to one j ...
or air flow. Land surface objects, or
landform A landform is a natural or artificial feature of the solid surface of the Earth or other planetary body A planet is an astronomical body Astronomy (from el, ἀστρονομία, literally meaning the science that studies the laws ...

landform
s, are definite physical objects (lines, points, areas) that differ from the surrounding objects. The most typical examples airlines of
watershed Watershed is a hydrological term, which has been adopted in other fields in a more or less figurative sense. It may refer to: Hydrology * Drainage divide, the line that separates neighbouring drainage basins ** European watershed * Drainage basin, ...
s,
stream A stream is a body of water (Lysefjord) in Norway Norway, officially the Kingdom of Norway,Names in the official and recognised languages: Bokmål Bokmål (, ; literally "book tongue") is an official written standard for the No ...

stream
patterns,
ridge A ridge or a mountain ridge is a geographical feature consisting of a chain of mountains or hills that form a continuous elevated crest for some distance. The sides of the ridge slope away from narrow top on either side. The lines along th ...

ridge
s, break-lines,
pool Pool may refer to: Water pool * Swimming pool A swimming pool, swimming bath, wading pool, paddling pool, or simply pool, is a structure designed to hold water to enable Human swimming, swimming or other leisure activities. Pools can be ...
s or borders of specific landforms.


See also

* Applications of global navigation satellite systems (GNSS) *
Cartographic relief depiction Terrain cartography or relief mapping is the depiction of the shape of the surface of the Earth on a map, using one or more of several techniques that have been developed. Terrain Relief map of Sierra Nevada, Spain Terrain or relief (a ...
(2D relief map) *
Digital terrain model A digital elevation model (DEM) is a 3D computer graphics 3D computer graphics, sometimes called CGI, 3DCG or three-dimensional computer graphics (in contrast to 2D computer graphics), are graphics that use a three-dimensional representation ...
*
Geographic information system A geographic information system (GIS) is a type of database In , a database is an organized collection of stored and accessed electronically from a . Where databases are more complex they are often developed using formal techniques. The ( ...
(GIS) *
GeomorphometryGeomorphometry, or geomorphometrics ( grc, γῆ, gê, earth + grc, μορφή, morphḗ, form, shape + grc, μέτρον, métron, measure), is the science and practice of measuring the characteristics of terrain, the shape of the surface of the E ...
*
Hypsometry Hypsometry (from Greek ὕψος, ''hupsos'', "height" and μέτρον, ''metron'', "measure") is the measurement of land elevation The elevation of a geographic location (geography), location is its height above or below a fixed reference po ...
*
Isostasy Isostasy (Greek ''ísos'' "equal", ''stásis'' "standstill") or isostatic equilibrium is the state of gravitational Gravity (), or gravitation, is a natural phenomenon by which all things with mass Mass is both a property Prope ...

Isostasy
* Physical terrain model * Relief ratio * Subterranea * Terrain awareness and warning system *
Terrane In geology Geology (from the Ancient Greek γῆ, ''gē'' ("earth") and -λoγία, ''-logia'', ("study of", "discourse")) is an Earth science concerned with the solid Earth, the rock (geology), rocks of which it is composed, and the processes ...
*
Topography Topography is the study of the forms and features of land surface Relief map of Sierra Nevada, Spain Terrain or relief (also topographical Topography is the study of the forms and features of land surfaces. The topography of an ...


References


Further reading


Boots on the ground
On military terrain from the perspective of the combat soldier. By Professor
Derek Gregory Derek Gregory Ph.D. (Cantab) FBA, FRSC (born 1 March 1951) is a British academic and world-renowned geographer A geographer is a physical scientist, social scientist and humanist whose area of study is geography, the study of Earth's natura ...


External links


Google Maps

Bing Maps
{{Wiktionary-inline, terrain Physical geography Topography Vertical datums