
A mountain is an elevated portion of the
Earth's crust
350px, Plates in the crust of Earth
Earth's crust is a thin shell on the outside of Earth, accounting for less than 1% of Earth's volume. It is the top component of the lithosphere, a division of Earth's layers that includes the Crust (geology), ...
, generally with steep sides that show significant exposed
bedrock
Bedrock in geology
Geology (from the γῆ, ''gē'' ("earth") and -λoγία, ''-logia'', ("study of", "discourse")) is a branch of concerned with both the liquid and , the of which it is composed, and the processes by which they cha ...

. A mountain differs from a
plateau
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 ...

in having a limited summit area, and is larger than a
hill
A hill is a 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 scie ...

, typically rising at least 300 metres (1000 feet) above the surrounding land. A few mountains are isolated
summits
A summit is a point on a surface that is higher in elevation than all points immediately adjacent to it. The topography, topographic terms acme, apex, peak (mountain peak), and zenith are synonymous.
The term (mountain top) is generally used ...
, but most occur in
mountain range
A mountain range is a series of mountains
ranged in a line and connected by high ground. A mountain system or mountain belt is a group of mountain ranges with similarity in form, structure, and alignment that have arisen from the same cause, us ...

s.
Mountains are formed through
tectonic forces,
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 ...

, or
volcanism
Volcanism (or volcanicity) is the phenomenon of eruption of molten rock (magma) onto the Earth#Surface, surface of the Earth or a solid-surface planet or moon, where lava, pyroclastics and volcanic gases erupt through a break in the surface called ...
,
which act on time scales of up to tens of millions of years.
Once mountain building ceases, mountains are slowly leveled through the action of
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 ...
, through
slumping
Slumping is a technique in which items are made in a kiln
, Wrecclesham, Surrey
Surrey () is a county in South East England which borders Kent to the east, East Sussex to the southeast, West Sussex to the south, Hampshire to the west, B ...
and other 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 occurring solid mass or aggregate of minerals or mineraloid matter. It is categori ...
, as well as through
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 ...

by
river
A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of wate ...

s and
glacier
A glacier (; ) is a persistent body of dense ice
Ice is into a state. Depending on the presence of such as particles of soil or bubbles of air, it can appear transparent or a more or less bluish-white color.
In the , ice is abunda ...

s.
High elevations on mountains produce
colder climates than at
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 ...

at similar latitude. These colder climates strongly affect the
ecosystems
An ecosystem (or ecological system) consists of all the organisms and the physical environment with which they interact. These biotic and abiotic components are linked together through nutrient cycles and energy flows. Energy enters the syste ...
of mountains: different elevations have different plants and animals. Because of the less hospitable terrain and climate, mountains tend to be used less for agriculture and more for resource extraction, such as
mining
Mining is the extraction of valuable mineral
In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occu ...

and
logging
Logging is the process of cutting, processing, and moving trees to a location for transport. It may include skidder, skidding, on-site processing, and loading of trees or trunk (botany), logs onto logging truck, trucks or flatcar#Skeleton car, s ...

, along with recreation, such as
mountain climbing
Mountaineering, or alpinism, is the set of outdoor activities
Outdoor recreation or outdoor activity refers to recreation
Recreation is an activity of leisure, leisure being discretionary time. The "need to do something for recreation" is a ...
and
skiing
Skiing is the use of ski
A ski is a narrow strip of semi-rigid material worn underfoot to glide over snow. Substantially longer than wide and characteristically employed in pairs, skis are attached to ski boot Ski boots are used in to p ...

.
The highest mountain on Earth is
Mount Everest
Mount Everest (Chinese
Chinese can refer to:
* Something related to China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the List of countries and dependencies by population, world's ...

in the
Himalayas
The Himalayas, or Himalaya (; Sanskrit
Sanskrit (; attributively , ; nominalization, nominally , , ) is a classical language of South Asia that belongs to the Indo-Aryan languages, Indo-Aryan branch of the Indo-European languages. It ar ...

of
Asia
Asia () is Earth's largest and most populous continent, located primarily in the Eastern Hemisphere, Eastern and Northern Hemisphere, Northern Hemisphere of the Earth, Hemispheres. It shares the continental landmass of Eurasia with the cont ...

, whose summit is above
mean sea level
There are several kinds of mean in mathematics
Mathematics (from Greek: ) includes the study of such topics as numbers (arithmetic and number theory), formulas and related structures (algebra), shapes and spaces in which they are contain ...
. The
highest known mountain on any planet in the Solar System is
Olympus Mons
Olympus Mons (; Latin
Latin (, or , ) is a classical language
A classical language is a language
A language is a structured system of communication
Communication (from Latin ''communicare'', meaning "to share" or "to be in re ...

on Mars at .
Definition

There is no universally accepted definition of a mountain. Elevation, volume, relief, steepness, spacing and continuity have been used as criteria for defining a mountain.
[ In the '']Oxford English Dictionary
The ''Oxford English Dictionary'' (''OED'') is the principal historical dictionary
A historical dictionary or dictionary on historical principles is a dictionary which deals not only with the latterday meanings of words but also the historica ...
'' a mountain is defined as "a natural elevation of the earth surface rising more or less abruptly from the surrounding level and attaining an altitude which, relatively to the adjacent elevation, is impressive or notable."[
Whether a landform is called a mountain may depend on local usage. outside ]Lawton, Oklahoma
Lawton is a city in, and the county seat
A county seat is an administrative centerAn administrative centre is a seat of regional administration or local government
Local government is a generic term for the lowest tiers of public administrat ...
, USA, is only from its base to its highest point. Whittow's ''Dictionary of Physical Geography'' states "Some authorities regard eminences above as mountains, those below being referred to as hills."
In the United Kingdom and the Republic of Ireland, a mountain is usually defined as any summit at least high, which accords with the official UK government's definition that a mountain, for the purposes of access, is a summit of or higher. In addition, some definitions also include a topographical prominence
In 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. T ...
requirement, such as that the mountain rises above the surrounding terrain. At one time the U.S. Board on Geographic Names
The United States Board on Geographic Names (BGN) is a federal body operating under the United States Secretary of the Interior
The United States secretary of the interior is the head of the United States Department of the Interior. The secreta ...
defined a mountain as being or taller, but has abandoned the definition since the 1970s. Any similar landform lower than this height was considered a hill. However, today, the United States Geological Survey
The United States Geological Survey, abbreviated USGS and formerly simply known as the Geological Survey, is a scientific government agency, agency of the Federal government of the United States, United States government. The scientists of the ...
(USGS) concludes that these terms do not have technical definitions in the US.
The UN Environmental Programme's definition of "mountainous environment" includes any of the following:[
* Class 1: Elevation greater than .
* Class 2: Elevation between and .
* Class 3: Elevation between and .
* Class 4: Elevation between and , with a slope greater than 2 degrees.
* Class 5: Elevation between and , with a slope greater than 5 degrees and/or elevation range within .
* Class 6: Elevation between and , with a elevation range within .
* Class 7: Isolated inner basins and plateaus less than in area that are completely surrounded by Class 1 to 6 mountains, but do not themselves meet criteria for Class 1 to 6 mountains.
Using these definitions, mountains cover 33% of Eurasia, 19% of South America, 24% of North America, and 14% of Africa.][ As a whole, 24% of the Earth's land mass is mountainous.]
Geology
There are three main types of mountains: 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 ...

, fold
Fold or folding may refer to:
Arts, entertainment, and media
*Fold (album), ''Fold'' (album), the debut release by Australian rock band Epicure
*Fold (poker), in the game of poker, to discard one's hand and forfeit interest in the current pot
*Ab ...
, and block
Block or blocked may refer to:
Arts, entertainment and media Broadcasting
* Block programming, the result of a programming strategy in broadcasting
* W242BX, a radio station licensed to Greenville, South Carolina, United States known as ''96.3 t ...
. All three types are formed from plate tectonics
upright=1.35, Diagram of the internal layering of Earth showing the lithosphere above the asthenosphere (not to scale)
Plate tectonics (from the la, label=Late Latin
Late Latin ( la, Latinitas serior) is the scholarly name for the written L ...
: when portions of the Earth's crust move, crumple, and dive. Compressional forces, uplift and intrusion of igneous matter forces surface rock upward, creating a landform higher than the surrounding features. The height of the feature makes it either a hill or, if higher and steeper, a mountain. Major mountains tend to occur in long linear arcs, indicating tectonic plate boundaries and activity.
Volcanoes
Volcanoes are formed when a plate is pushed below another plate
A, or a, is the first Letter (alphabet), letter and the first vowel letter of the English alphabet, modern English alphabet and the ISO basic Latin alphabet. Its name in English is English alphabet#Letter names, ''a'' (pronounced ), plural En ...

, or at a mid-ocean ridge
A mid-ocean ridge (MOR) is a seafloor mountain system formed by plate tectonics
File:Earth cutaway schematic-en.svg, upright=1.35, Diagram of the internal layering of Earth showing the lithosphere above the asthenosphere (not to scale)
Plate ...
or hotspot. At a depth of around 100 km, melting occurs in rock above the slab (due to the addition of water), and forms magma
Magma () is the molten or semi-molten natural material from which all igneous rock
Igneous rock (derived from the Latin word ''ignis'' meaning fire), or magmatic rock, is one of the three main The three types of rocks, rock types, the others ...

that reaches the surface. When the magma reaches the surface, it often builds a volcanic mountain, such as a shield volcano
A shield volcano is a type of volcano
A volcano is a rupture in the of a , such as , that allows hot , , and to escape from a below the surface.
On Earth, volcanoes are most often found where are or , and most are found underwater. Fo ...

or a stratovolcano
A stratovolcano, also known as a composite volcano, is a conical
A cone is a three-dimensional space, three-dimensional geometric shape that tapers smoothly from a flat base (frequently, though not necessarily, circular) to a point called the ...

.[ Examples of volcanoes include ]Mount Fuji
, located on the island of Honshū
, historically called , is the largest and most populous main island of Japan
, image_flag = Flag of Japan.svg
, alt_flag = Centered deep red circle on a white r ...

in Japan and Mount Pinatubo
Mount Pinatubo ( xsb, Bakil nin Pinatobo; pam, Bunduk/Bulkan ning Pinatubu, Bunduk ning Apu Malyari; pag, Palandey/Bulkan na Pinatubu; ilo, Bantay Pinatubo; tgl, Bundok/Bulkang Pinatubo ) is an active volcano, active stratovolcano in the ...

in the Philippines. The magma does not have to reach the surface in order to create a mountain: magma that solidifies below ground can still form dome mountain
Structural dome on Baffin Island, seen in a planation surface.">planation_surface.html" ;"title="Baffin Island, seen in a planation surface">Baffin Island, seen in a planation surface.
A dome is a feature in structural geology consisting of sy ...
s, such as Navajo Mountain
, photo = NavajoMtn.jpg
, photo_caption = Navajo Mountain and Lake Powell, looking southeast from the Kaiparowits Plateau
, elevation_ft = 10348
, elevation_ref =
, prominence_ft = 4226
, prominence_ref =
, listing =
, location =
, m ...
in the US.
Fold mountains
Fold mountains occur when two plates collide: shortening occurs along thrust faults and the crust is overthickened. Since the less dense continental crust
Continental crust is the layer of igneous
Igneous rock (derived from the Latin
Latin (, or , ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally spoken in the ...
"floats" on the denser mantle
Mantle may refer to:
*Mantle (geology)
A mantle is a layer inside a planetary body
A planet is an astronomical body
Astronomy (from el, ἀστρονομία, literally meaning the science that studies the laws of the stars) is a n ...
rocks beneath, the weight of any crustal material forced upward to form hills, plateau
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 ...

s or mountains must be of a much greater volume forced downward into the mantle. Thus the continental crust is normally much thicker under mountains, compared to lower lying areas. Rock can fold
Fold or folding may refer to:
Arts, entertainment, and media
*Fold (album), ''Fold'' (album), the debut release by Australian rock band Epicure
*Fold (poker), in the game of poker, to discard one's hand and forfeit interest in the current pot
*Ab ...
either symmetrically or asymmetrically. The upfolds are anticline
In structural geology, an anticline is a type of Fold (geology), fold that is an arch-like shape and has its oldest Bed (geology), beds at its core, whereas a syncline is the inverse of a anticline. A typical anticline is convex curve, conv ...

s and the downfolds are syncline
In structural geology
Structural geology is the study of the three-dimensional distribution of Rock (geology), rock units with respect to their Deformation (geology), deformational histories. The primary goal of structural geology is to use meas ...

s: in asymmetric folding there may also be recumbent and overturned folds. The Balkan Mountains
The Balkan mountain range (Bulgarian
Bulgarian may refer to:
* Something of, from, or related to the country of Bulgaria
* Bulgarians, a South Slavic ethnic group
* Bulgarian language, a Slavic language
* Bulgarian alphabet
* A citizen of Bulgar ...
and the Jura Mountains
The Jura Mountains ( , , , ; french: Massif du Jura; german: Juragebirge; it, Massiccio del Giura, rm, Montagnas da Jura) are a sub-alpine mountain range a short distance north of the Western Alps and mainly demarcate a long part of the ...

are examples of fold mountains.
Block mountains
Block mountains are caused by faults in the crust: a plane where rocks have moved past each other. When rocks on one side of a fault rise relative to the other, it can form a mountain. The uplifted blocks are block mountains or horsts. The intervening dropped blocks are termed graben
In geology
Geology (from the γῆ, ''gē'' ("earth") and -λoγία, ''-logia'', ("study of", "discourse")) is a branch of concerned with both the liquid and , the of which it is composed, and the processes by which they change over ti ...

: these can be small or form extensive rift valley
A rift valley is a linear shaped lowland between several Highland, highlands or mountain ranges created by the action of a geologic rift. Rifts are formed as a result of the pulling apart of the lithosphere due to extensional tectonics. The ...
systems. This form of landscape
A landscape is the visible features of an area 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) an ...

can be seen in East Africa
East Africa, Eastern Africa, or East of Africa is the eastern sub-region
A subregion is a part of a larger region or continent and is usually based on location. Cardinal directions, such as south or southern, are commonly used to define a subr ...
, the Vosges
The Vosges ( , ; german: Vogesen ; gsw, Vogese) are a range of low mountains in Eastern France
France (), officially the French Republic (french: link=no, République française), is a country primarily located in Western Europe, consis ...
and Rhine
), Surselva
Surselva Region is one of the eleven administrative districts
Administrative division, administrative unitArticle 3(1). , country subdivision, administrative region, subnational entity, first-level subdivision, as well as many s ...
valley, and the Basin and Range Province
The Basin and Range Province is a vast physiographic region
Physiographic regions of the world are a means of defining Earth
Earth is the third planet from the Sun and the only astronomical object known to harbor life. About 29% of Eart ...
of Western North America. These areas often occur when the regional stress is extensional and the crust is thinned.
Erosion
During and following uplift, mountains are subjected to the agents of 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 ...

(water, wind, ice, and gravity) which gradually wear the uplifted area down. Erosion causes the surface of mountains to be younger than the rocks that form the mountains themselves.[ produce characteristic landforms, such as ]pyramidal peak
A pyramidal peak, sometimes called a glacial horn in extreme cases, is an angular, sharply pointed mountain peak which results from the cirque erosion due to multiple glaciers diverging from a central point. Pyramidal peaks are often examples o ...
s, knife-edge arête
An arête is a narrow ridge of Rock (geology), rock which separates two valleys. It is typically formed when two glaciers erode parallel U-shaped valleys. Arêtes can also form when two glacial cirque (landform), cirques erode headwards towards ...
s, and bowl-shaped cirque
A cirque (; from the Latin word ''circus'') is an amphitheatre
An amphitheatre ( British English) or amphitheater ( American English; both ) is an open-air venue used for entertainment, performances, and sports. The term derives from the an ...
s that can contain lakes. Plateau
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 ...

mountains, such as the Catskills
The Catskill Mountains, also known as the Catskills, are a physiographic province of the larger Appalachian Mountains
The Appalachian Mountains, often called the Appalachians, are a system of mountains in eastern North America
N ...

, are formed from the erosion of an uplifted plateau.
Climate
Climate in the mountains becomes colder at high 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 ...

s, due to an interaction between radiation
In physics
Physics is the natural science that studies matter, its Elementary particle, fundamental constituents, its Motion (physics), motion and behavior through Spacetime, space and time, and the related entities of energy and f ...

and convection
Convection is single or multiphase fluid flow that occurs Spontaneous process, spontaneously due to the combined effects of material property heterogeneity and body forces on a fluid, most commonly density and gravity (see buoyancy). When t ...

. Sunlight in the visible spectrum
The visible spectrum is the portion of the that is to the . in this range of s is called ' or simply . A typical will respond to wavelengths from about 380 to about 750 . In terms of frequency, this corresponds to a band in the vicinity of ...
hits the ground and heats it. The ground then heats the air at the surface. If radiation
In physics
Physics is the natural science that studies matter, its Elementary particle, fundamental constituents, its Motion (physics), motion and behavior through Spacetime, space and time, and the related entities of energy and f ...

were the only way to transfer heat from the ground to space, the greenhouse effect
The greenhouse effect is the process by which radiation from a planet's atmosphere warms the planet's surface to a temperature above what it would be without this atmosphere.
Radiatively active gases (i.e., greenhouse gas
A greenhou ...

of gases in the atmosphere would keep the ground at roughly , and the temperature would decay exponentially with height.
However, when air is hot, it tends to expand, which lowers its density. Thus, hot air tends to rise and transfer heat upward. This is the process of convection
Convection is single or multiphase fluid flow that occurs Spontaneous process, spontaneously due to the combined effects of material property heterogeneity and body forces on a fluid, most commonly density and gravity (see buoyancy). When t ...

. Convection comes to equilibrium when a parcel of air at a given altitude has the same density as its surroundings. Air is a poor conductor of heat, so a parcel of air will rise and fall without exchanging heat. This is known as an adiabatic process
In thermodynamics
Thermodynamics is a branch of physics that deals with heat, Work (thermodynamics), work, and temperature, and their relation to energy, entropy, and the physical properties of matter and radiation. The behavior of these qu ...

, which has a characteristic pressure-temperature dependence. As the pressure gets lower, the temperature decreases. The rate of decrease of temperature with elevation is known as the adiabatic lapse rate
The lapse rate is the rate at which an atmospheric variable, normally temperature
Temperature is a physical quantity that expresses hot and cold. It is the manifestation of thermal energy, present in all matter, which is the source of the o ...
, which is approximately 9.8 °C per kilometre (or per 1000 feet) of altitude.[
Note that the presence of water in the atmosphere complicates the process of convection. Water vapor contains latent ]heat of vaporization
The enthalpy of vaporization (symbol ), also known as the (latent) heat of vaporization or heat of evaporation, is the amount of energy (enthalpy
Enthalpy , a property of a thermodynamic system, is the sum of the system's internal energy and ...
. As air rises and cools, it eventually becomes saturated and cannot hold its quantity of water vapor. The water vapor condenses (forming cloud
In meteorology, a cloud is an aerosol consisting of a visible mass of minute liquid drop (liquid), droplets, ice crystals, frozen crystals, or other particulates, particles suspended in the atmosphere of a planetary body or similar space. Wate ...

s), and releases heat, which changes the lapse rate from the dry adiabatic lapse rate
The lapse rate is the rate at which an atmospheric variable, normally temperature
Temperature is a physical quantity that expresses hot and cold. It is the manifestation of thermal energy, present in all matter, which is the source of the o ...
to the moist adiabatic lapse rate
The lapse rate is the rate at which an atmospheric variable, normally temperature in Earth's atmosphere, falls with altitude. ''Lapse rate'' arises from the word ''lapse'', in the sense of a gradual fall.
It corresponds to the vertical component o ...
(5.5 °C per kilometre or per 1000 feet)
The actual lapse rate can vary by altitude and by location.
Therefore, moving up 100 metres on a mountain is roughly equivalent to moving 80 kilometres (45 miles or 0.75° of latitude
In geography
Geography (from 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 planets. The first person to use the ...

) towards the nearest pole.[ This relationship is only approximate, however, since local factors such as proximity to oceans (such as the Arctic Ocean) can drastically modify the climate. As the altitude increases, the main form of ]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 ...
becomes snow
Snow comprises individual ice
Ice is water
Water (chemical formula H2O) is an , transparent, tasteless, odorless, and , which is the main constituent of 's and the s of all known living organisms (in which it acts as a ). ...

and the winds increase.[
The effect of the climate on the ecology at an elevation can be largely captured through a combination of amount of precipitation, and the ]biotemperature
600px, Holdridge life zone classification scheme. Although conceived as three-dimensional by its originator, it is usually shown as a two-dimensional array of hexagons in a triangular frame.
The Holdridge life zones system is a global bioclimatic s ...
, as described by Leslie Holdridge
Leslie Ransselaer Holdridge (September 29, 1907 – June 19, 1999) was an American botanist and climatologist. He was the father of composer Lee Holdridge.
Career
Image:Lifezones Pengo.svg, 300px, Diagram of life zone classifications.
In his f ...
in 1947. Biotemperature is the mean temperature; all temperatures below are considered to be 0 °C. When the temperature is below 0 °C, plants are dormant, so the exact temperature is unimportant. The peaks of mountains with permanent snow can have a biotemperature below .
Ecology
The colder climate on mountains affects the plants and animals residing on mountains. A particular set of plants and animals tend to be adapted to a relatively narrow range of climate. Thus, ecosystems tend to lie along elevation bands of roughly constant climate. This is called altitudinal zonation
Altitudinal zonation (or elevational zonation) in mountainous regions describes the natural layering of ecosystems that occurs at distinct elevations due to varying environmental conditions. Temperature
Temperature ( ) is a physical quan ...
.
In regions with dry climates, the tendency of mountains to have higher precipitation as well as lower temperatures also provides for varying conditions, which enhances zonation.
Some plants and animals found in altitudinal zones tend to become isolated since the conditions above and below a particular zone will be inhospitable and thus constrain their movements or dispersal
Dispersal may refer to:
* Biological dispersal, the movement of organisms from their birth site to their breeding site, or from one breeding site to another
** Dispersal vector, forces that carry seeds for plants
** Oceanic dispersal, the movement ...
. These isolated ecological systems are known as sky island
Sky islands are isolated mountains surrounded by radically different lowland environments. The term originally referred to those found near the southern borders of the U.S. state
In the , a state is a , of which there are currently 50 ...
s.
Altitudinal zones tend to follow a typical pattern. At the highest elevations, trees cannot grow, and whatever life may be present will be of the alpine
Alpine may refer to:
Places
* Alps, a European mountain range
* Alpine states, associated with the mountain range, or relating to any lofty mountain areas
* Mountainous or alpine; the mountains.
Australia
* Alpine, New South Wales, a Northern Vill ...
type, resembling tundra
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 ...

. Just below the tree line
The tree line is the edge of the habitat at which tree
In botany, a tree is a perennial plant with an elongated Plant stem, stem, or trunk (botany), trunk, supporting branches and leaves in most species. In some usages, the definition of ...

, one may find subalpine
Montane ecosystems are found on the slopes of mountain
A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. A mountain differs from a plateau in having a limited summit area ...
forests of trees, which can withstand cold, dry conditions. Below that, montane forest
Montane ecosystems are found on the slopes of mountains. The alpine climate in these regions strongly affects the ecosystem because temperatures lapse rate, fall as elevation increases, causing the ecosystem to stratify. This stratification is a c ...
s grow. In the temperate portions of the earth, those forests tend to be needleleaf trees, while in the tropics, they can be broadleaf tree
A broad-leaved, broad-leaf, or broadleaf tree is any tree within the diverse botanical group of angiosperms
The flowering plants, also known as Angiospermae (), or Magnoliophyta (), are the most diverse group of land plants, with 64 orders, 416 ...
s growing in a rain forest
Rainforests are forest
A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing and ecological func ...

.
Mountains and humans
The highest known permanently tolerable altitude is at . At very high altitudes, the decreasing atmospheric pressure means that less oxygen is available for breathing, and there is less protection against solar radiation ().[ Above elevation, there is not enough oxygen to support human life. This is known as the "]death zone
In mountaineering, the death zone refers to altitudes above a certain point where the pressure of oxygen is Effects of high altitude on humans, insufficient to sustain human life for an extended time span. This point is generally tagged as , less ...
". The summits of Mount Everest
Mount Everest (Chinese
Chinese can refer to:
* Something related to China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the List of countries and dependencies by population, world's ...

and are in the death zone.
Mountain societies and economies
Mountains are generally less preferable for human
Humans (''Homo sapiens'') are the most abundant and widespread species
In biology, a species is the basic unit of biological classification, classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A speci ...

habitation than lowlands, because of harsh weather and little level ground suitable for 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 ...

. While 7% of the land area of Earth is above ,[ only 140 million people live above that altitude and only 20-30 million people above elevation. About half of mountain dwellers live in the ]Andes
The Andes, Andes Mountains or Andean Mountains ( es, Cordillera de los Andes) are the List of mountain ranges#Mountain ranges by length, longest continental mountain range in the world, forming a continuous highland along the western edge of Sou ...

, Central Asia, and Africa.[
]
With limited access to infrastructure, only a handful of human communities exist above of elevation. Many are small and have heavily specialized economies, often relying on industries such as agriculture, mining, and tourism. An example of such a specialized town is La Rinconada, Peru
La Rinconada is a town in the Peruvian Andes
The Andes, Andes Mountains or Andean Mountains ( es, Cordillera de los Andes) are the List of mountain ranges#Mountain ranges by length, longest continental mountain range in the world, forming a con ...
, a gold-mining town and the highest elevation human habitation at . A counterexample is El Alto
El Alto (Spanish for "The Heights") is the second-largest city in Bolivia, located adjacent to La Paz in Pedro Domingo Murillo Province on the Altiplano highlands. El Alto is today one of Bolivia's fastest-growing urban centers, with an estimate ...

, Bolivia
Bolivia ; ay, Wuliwya ; Quechuan languages, Quechua: ''Puliwya'' , officially the Plurinational State of Bolivia, is a landlocked country located in western-central South America. The constitutional capital is Sucre, while the seat of g ...

, at , which has a highly diverse service and manufacturing economy and a population of nearly 1 million.
Traditional mountain societies rely on agriculture, with higher risk of crop failure
Harvesting is the process of gathering a ripe crop from the field
Field may refer to:
Expanses of open ground
* Field (agriculture), an area of land used for agricultural purposes
* Airfield, an aerodrome that lacks the infrastructure of an ...
than at lower elevations. Minerals often occur in mountains, with mining
Mining is the extraction of valuable mineral
In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid chemical compound with a fairly well-defined chemical composition and a specific crystal structure that occu ...

being an important component of the economics of some montane societies. More recently, tourism
Tourism is travel
Travel is the movement of people between distant geographical location
In geography
Geography (from Greek: , ''geographia'', literally "earth description") is a field of science devoted to the study of th ...

supports mountain communities, with some intensive development around attractions such as national park#REDIRECT National park
A national park is a park in use for Conservation (ethic), conservation purposes, created and protected by national governments. Often it is a reserve of natural, semi-natural, or developed land that a sovereign state dec ...

s or ski resorts
A ski resort is a resort developed for skiing
Skiing is a means of transport using skis to glide on snow. Variations of purpose include basic transport, a recreational activity, or a competitive winter sport. Many types of competitive skiing ...

.[ About 80% of ]mountain people
Hill people, also referred to as mountain people, is a general term for people who live in the hill
A hill is a landform
A landform is a natural or artificial feature of the solid surface of the Earth or other planetary body. Landforms t ...
live below the poverty line.[
Most of the world's ]river
A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of wate ...

s are fed from mountain sources, with snow acting as a storage mechanism for downstream users.[ More than half of humanity depends on mountains for water.
In ]geopolitics
Geopolitics (from Greek#REDIRECT 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 approxi ...
mountains are often seen as preferable "natural boundaries
A natural border is a border
Borders are geographic boundaries of political entities or legal jurisdiction
Jurisdiction (from Latin ''Wikt:ius#Latin, juris'' 'law' + ''Wikt:dictio, dictio'' 'declaration') is the practical authority granted t ...
" between polities.
Mountaineering
Mountain climbing, or alpinism is the sport
Sport pertains to any form of Competition, competitive physical activity or game that aims to use, maintain or improve physical ability and Skill, skills while providing enjoyment to participants and, in some cases, entertainment to spectato ...

, hobby
A hobby is considered to be a regular activity that is done for enjoyment, typically during one's leisure time
Leisure has often been defined as a quality of experience or as free time. Free time is time
Time is the indefinite ...

or profession
A Profession is a disciplined group of individuals who adhere to ethical standards and who hold themselves out as, and are accepted by the public as possessing special knowledge and skills in a widely recognised body of learning derived from r ...

of hiking, skiing, and climbing mountains. While mountaineering began as attempts to reach the highest point of unclimbed big mountains it has branched into specializations that address different aspects of the mountain and consists of three areas: rock-craft, snow-craft and skiing, depending on whether the route chosen is over rock
Rock most often refers to:
* Rock (geology)
A rock is any naturally occurring solid mass or aggregate of minerals or mineraloid matter. It is categorized by the minerals included, its Chemical compound, chemical composition and the way in w ...
, snow
Snow comprises individual ice
Ice is water
Water (chemical formula H2O) is an , transparent, tasteless, odorless, and , which is the main constituent of 's and the s of all known living organisms (in which it acts as a ). ...

or ice
Ice is water
Water (chemical formula H2O) is an , transparent, tasteless, odorless, and , which is the main constituent of 's and the s of all known living organisms (in which it acts as a ). It is vital for all known forms of , eve ...

. All require experience, athletic ability, and technical knowledge of the terrain to maintain safety.
Mountains as sacred places
Mountains often play a significant role in religion
Religion is a social
Social organisms, including humans, live collectively in interacting populations. This interaction is considered social whether they are aware of it or not, and whether the exchange is voluntary/involuntary.
Etymology ...

. There are for example a number of sacred mountains within Greece
Greece ( el, Ελλάδα, Elláda, ), officially the Hellenic Republic, is a country located in Southeastern Europe
Southeast Europe or Southeastern Europe () is a geographical subregion
A subregion is a part of a larger region
In geogr ...

such as Mount Olympus
Mount Olympus (; el, Όλυμπος, Ólympos, also , ) is the highest mountain
A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. A mountain differs from a plateau in ...

which was held to be the home of the gods. In Japanese culture, the 3,776.24 m (12,389 ft) volcano of Mount Fuji
, located on the island of Honshū
, historically called , is the largest and most populous main island of Japan
, image_flag = Flag of Japan.svg
, alt_flag = Centered deep red circle on a white r ...

is also held to be sacred with tens of thousands of Japanese ascending it each year. Mount Kailash
Mount Kailash (also Kailasa; ''Kangrinboqê'' or ''Gang Rinpoche''; Tibetan: གངས་རིན་པོ་ཆེ; ; sa, कैलास, ), is a high peak in the Kailash Range (Gangdisê Mountains), which forms part of the Transhim ...

, in the Tibet Autonomous Region
The Tibet Autonomous Region (TAR) or Xizang Autonomous Region, often shortened to Tibet or Xizang, is a province
A province is almost always an administrative division
Administrative division, administrative unitArticle 3(1). , count ...
of China, is considered to be sacred in four religions: Hinduism
Hinduism () is an Indian religion
Indian religions, sometimes also termed Dharmic religions or Indic religions, are the religions that originated in the Indian subcontinent. These religions, which include Hinduism, Jainism, Buddhism, ...

, Bon
Bon, also spelled Bön () is considered to be the native pre-Buddhist religious tradition of Tibet. A distinction is sometimes made between:
# the Old Bon or Bön nying (), dating back to the pre-dynastic era;
# the Eternal Bon or Yungdrung B ...

, Buddhism
Buddhism (, ) is the world's fourth-largest religion
Religion is a social
Social organisms, including humans, live collectively in interacting populations. This interaction is considered social whether they are aware of it or not, and ...

, and Jainism
Jainism (), traditionally known as ''Jain Dharma'', is an ancient Indian religion. It is one of the oldest Indian religions. The three main pillars of Jainism are ''Ahimsa in Jainism, ahiṃsā'' (non-violence), ''anekāntavāda'' (non-absolut ...

. In Ireland
Ireland ( ; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the Atlantic Ocean, North Atlantic. It is separated from Great Britain to its east by the North Channel (Great Britain and Ireland), North Channel, the Irish Sea ...

, pilgrimage
A pilgrimage is a journey, often into an unknown or foreign place, where a person goes in search of new or expanded meaning about their self, others, nature, or a higher good, through the experience. It can lead to a personal transformation, aft ...
s are made up the Mount Brandon
Mount Brandon or Brandon (), at , is one of the ten highest peaks in Ireland, being the 8th–highest peak in Ireland
Ireland (; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the North Atlantic Ocean, North Atlantic. I ...

by Irish Catholic
Irish most commonly refers to:
* Someone or something of, from, or related to:
** Ireland
Ireland (; ga, Éire ; Ulster Scots dialect, Ulster-Scots: ) is an island in the North Atlantic Ocean, North Atlantic. It is separated from Great Brit ...
s. The Himalaya
The Himalayas, or Himalaya (; Sanskrit: , "snow", "dwelling", "abode"), are a mountain range in Asia separating the plains of the Indian subcontinent from the Tibetan Plateau. The range has some of the planet's highest peaks, including the ...

n peak of Nanda Devi
Nanda Devi is the second highest mountain in India
India (Hindi: ), officially the Republic of India (Hindi: ), is a country in South Asia. It is the List of countries and dependencies by population, second-most populous country, the Li ...

is associated with the Hindu
Hindus (; ) are persons who regard themselves as culturally, ethnically, or religiously adhering to aspects of Hinduism
Hinduism () is an Indian religion
Indian religions, sometimes also termed Dharmic religions or Indic re ...

goddesses Nanda and Sunanda; it has been off-limits to climbers since 1983. Mount Ararat
Mount Ararat ( ; hy, Մասիս, Masis and ; ku, Çiyayê Agirî; ) is a snow-capped and dormant compound volcano in the extreme east of Turkey
Turkey ( tr, Türkiye ), officially the Republic of Turkey, is a country straddling S ...

is a sacred mountain, as it is believed to be the landing place of Noah's Ark
Noah's Ark ( he, תיבת נח; Biblical Hebrew: ''Tevat Noaḥ'')The word "ark" in modern English comes from Old English ''aerca'', meaning a chest or box. (See Cresswell 2010, p.22) The Hebrew word for the vessel, ''teva'', occurs twice in ...

. In Europe and especially in the Alps
The Alps ; german: Alpen ; it, Alpi ; rm, Alps; sl, Alpe ) are the highest and most extensive mountain range
A mountain range is a series of mountains
ranged in a line and connected by high ground. A mountain system or mountain belt ...

, summit cross
A summit cross (german: Gipfelkreuz) is a cross
A cross is a geometrical figure consisting of two intersecting lines or bars, usually perpendicular to each other. The lines usually run vertically and horizontally.
A cross of oblique lines, in ...
es are often erected on the tops of prominent mountains.
Superlatives
Heights of mountains are typically measured above sea level
Above may refer to:
*Above (artist)
Tavar Zawacki formerly known as 'ABOVE' (born 1981) is an American abstract art
Abstract art uses visual language of shape, form, color and line to create a composition which may exist with a degree of ind ...
. Using this metric, Mount Everest
Mount Everest (Chinese
Chinese can refer to:
* Something related to China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the List of countries and dependencies by population, world's ...

is the highest mountain on Earth, at . There are at least 100 mountains with heights of over above sea level
Above may refer to:
*Above (artist)
Tavar Zawacki formerly known as 'ABOVE' (born 1981) is an American abstract art
Abstract art uses visual language of shape, form, color and line to create a composition which may exist with a degree of ind ...
, all of which are located in central and southern Asia. The highest mountains above sea level are generally not the highest above the surrounding terrain. There is no precise definition of surrounding base, but Denali
Denali (; also known as Mount McKinley, its former official name) is the highest mountain peak in North America, with a summit elevation of above sea level. With a topographic prominence of and a topographic isolation of , Denali is the List ...

, Mount Kilimanjaro
Mount Kilimanjaro () is a dormant volcano in Tanzania. It has three volcanic cones: Kibo, Mawenzi, and Shira. It is the highest African mountains, mountain in Africa and the highest single free-standing mountain in the world: above sea le ...

and Nanga Parbat
Nanga Parbat (; ), known locally as Diamer (), is the ninth-highest mountain on Earth, its summit at above sea level. Lying immediately southeast of the northernmost bend of the Indus river
The Indus ( ) is a transboundary river
A tr ...

are possible candidates for the tallest mountain on land by this measure. The bases of mountain islands are below sea level, and given this consideration Mauna Kea
Mauna Kea (; ; abbreviation for ''Mauna a Wākea''); is a dormant volcano
A volcano is a rupture in the Crust (geology), crust of a Planet#Planetary-mass objects, planetary-mass object, such as Earth, that allows hot lava, volcanic ash, an ...

( above sea level) is the world's tallest mountain and volcano
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 a ...

, rising about from the Pacific Ocean
The Pacific Ocean is the largest and deepest of Earth
Earth is the third planet from the Sun and the only astronomical object known to harbour and support life. 29.2% of Earth's surface is land consisting of continents and islands. ...

floor.
The highest mountains are not generally the most voluminous. Mauna Loa
Mauna Loa ( or ; Hawaiian
Hawaiian may refer to:
* Hawaii state residents, regardless of ancestry
* Native Hawaiians, the current term for the indigenous people of the Hawaiian Islands or their descendants
* Hawaiian language
Historic uses
* ...

() is the largest mountain on Earth in terms of base area (about ) and volume (about ). Mount Kilimanjaro
Mount Kilimanjaro () is a dormant volcano in Tanzania. It has three volcanic cones: Kibo, Mawenzi, and Shira. It is the highest African mountains, mountain in Africa and the highest single free-standing mountain in the world: above sea le ...

is the largest non-shield volcano in terms of both base area () and volume (). Mount Logan
Mount Logan () is the highest mountain
A mountain is an elevated portion of the Earth's crust, generally with steep sides that show significant exposed bedrock. A mountain differs from a plateau in having a limited summit area, and is l ...

is the largest non-volcanic mountain in base area ().
The highest mountains above sea level are also not those with peaks farthest from the centre of the Earth, because the figure of the Earth
Figure of the Earth is a Jargon, term of art in geodesy that refers to the size and shape used to model Earth. The size and shape it refers to depend on context, including the precision needed for the model. The Spherical Earth, sphere is an app ...
is not spherical. Sea level closer to the equator is several miles farther from the centre of the Earth. The summit of Chimborazo
Chimborazo () is a currently inactive stratovolcano in the Cordillera Occidental range of the Andes
The Andes, Andes Mountains or Andean Mountains ( es, Cordillera de los Andes) are the List of mountain ranges#Mountain ranges by length, long ...
, Ecuador
Ecuador ( ; ; Quechua
Quechua may refer to:
*Quechua people, several indigenous ethnic groups in South America, especially in Peru
*Quechuan languages, a Native South American language family spoken primarily in the Andes, derived from a ...

's tallest mountain, is usually considered to be the farthest point from the Earth's centre, although the southern summit of Peru
,
, image_flag = Flag_of_Peru.svg
, image_coat = Escudo_nacional_del_Perú.svg
, other_symbol = Great Seal of the State
, other_symbol_type = Seal (device), National seal
, national_mott ...

's tallest mountain, Huascarán
Huascarán () (Quechuan languages, Quechua: Waskaran) or Mataraju is a mountain in the Peruvian province of Yungay Province, Yungay (Ancash Region, Ancash Department), situated in the Cordillera Blanca range of the western Andes. The highest south ...

, is another contender.[
] Both have elevations above sea level more than less than that of Everest.
See also
* List of mountain ranges
This is a list of mountain range
A mountain range is a series of mountains
ranged in a line and connected by high ground. A mountain system or mountain belt is a group of mountain ranges with similarity in form, structure, and alignment that h ...
* List of peaks by prominence
This is a list of mountain peaks ordered by their topographic prominence.
Terminology
The prominence of a peak is the minimum height of climb to the summit on any route from a higher peak, or from sea level if there is no higher peak. The lowest ...
* List of ski areas and resorts
This is a list of ski areas and resorts around the world.
Africa
Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjac ...
* Lists of mountains
*
References
External links
*
*
{{Authority control
Geography terminology
Earth's crust