The natural environment or natural world encompasses all biotic and abiotic things occurring naturally , meaning in this case not artificial . The term is most often applied to Earth or some parts of Earth. This environment encompasses the interaction of all living species , climate , weather and natural resources that affect human survival and economic activity. The concept of the natural environment can be distinguished as components:
153-487: In contrast to the natural environment is the built environment . Built environments are where humans have fundamentally transformed landscapes such as urban settings and agricultural land conversion , the natural environment is greatly changed into a simplified human environment. Even acts which seem less extreme, such as building a mud hut or a photovoltaic system in the desert , the modified environment becomes an artificial one. Though many animals build things to provide
306-461: A cardiovascular system in that they circulate people and materials throughout a city similar to how veins distribute energy and materials to the cells. Pedestrian circulation is vital for the walkability of a city and general access on a human scale. The quality of sidewalks and walkways have an impact on safety and accessibility for those using these spaces. Public transportation is essential in urban areas, particularly in cities and areas that have
459-540: A circumstellar disk , and then the planets grow out of that disk with the Sun. A nebula contains gas, ice grains, and dust (including primordial nuclides ). According to nebular theory , planetesimals formed by accretion , with the primordial Earth being estimated as likely taking anywhere from 70 to 100 million years to form. Estimates of the age of the Moon range from 4.5 Ga to significantly younger. A leading hypothesis
612-598: A better environment for themselves, they are not human, hence beaver dams and the works of mound-building termites are thought of as natural. People cannot find absolutely natural environments on Earth,naturalness usually varies in a continuum, from 100% natural in one extreme to 0% natural in the other. The massive environmental changes of humanity in the Anthropocene have fundamentally effected all natural environments including: climate change , biodiversity loss and pollution from plastic and other chemicals in
765-441: A capacity to grow , respond to stimuli , reproduce and, through natural selection , adapt to their environment in successive generations. More complex living organisms can communicate through various means. An ecosystem (also called an environment) is a natural unit consisting of all plants, animals, and micro-organisms ( biotic factors) in an area functioning together with all of the non-living physical ( abiotic ) factors of
918-492: A common barycenter every 27.32 days relative to the background stars. When combined with the Earth–Moon system's common orbit around the Sun, the period of the synodic month , from new moon to new moon, is 29.53 days. Viewed from the celestial north pole , the motion of Earth, the Moon, and their axial rotations are all counterclockwise . Viewed from a vantage point above the Sun and Earth's north poles, Earth orbits in
1071-548: A counterclockwise direction about the Sun. The orbital and axial planes are not precisely aligned: Earth's axis is tilted some 23.44 degrees from the perpendicular to the Earth–Sun plane (the ecliptic ), and the Earth-Moon plane is tilted up to ±5.1 degrees against the Earth–Sun plane. Without this tilt, there would be an eclipse every two weeks, alternating between lunar eclipses and solar eclipses . The Hill sphere , or
1224-639: A decreased food supply for the wildlife in an area. The atmosphere of the Earth serves as a key factor in sustaining the planetary ecosystem. The thin layer of gases that envelops the Earth is held in place by the planet's gravity. Dry air consists of 78% nitrogen , 21% oxygen , 1% argon , inert gases and carbon dioxide . The remaining gases are often referred to as trace gases. The atmosphere includes greenhouse gases such as carbon dioxide, methane, nitrous oxide and ozone. Filtered air includes trace amounts of many other chemical compounds . Air also contains
1377-542: A disadvantage. The historical segregation has contributed to environmental injustice, as these neighborhoods suffer from hotter summers since urban asphalt absorbs more heat than trees and grass. The effects of spatial segregation initiatives in the built environment, such as redlining in the 1930s and 1940s, are long lasting. The inability to feasibly move from forcibly economically depressed areas into more prosperous ones creates fiscal disadvantages that are passed down generationally. With proper public education access tied to
1530-410: A diverse population and income range. Agricultural production accounts for roughly 52% of U.S. land use. Not only does population growth cause an expansion of cities, it also necessitates more agriculture to accommodate the demand for food for an expanding population. "Built environment" as a term was coined in the 1980s, becoming widespread in the 1990s and places the concept in direct contrast to
1683-420: A full rotation about its axis so that the Sun returns to the meridian . The orbital speed of Earth averages about 29.78 km/s (107,200 km/h; 66,600 mph), which is fast enough to travel a distance equal to Earth's diameter, about 12,742 km (7,918 mi), in seven minutes, and the distance from Earth to the Moon, 384,400 km (238,900 mi), in about 3.5 hours. The Moon and Earth orbit
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#17327722596921836-421: A globe-spanning mid-ocean ridge system. At Earth's polar regions , the ocean surface is covered by seasonally variable amounts of sea ice that often connects with polar land, permafrost and ice sheets , forming polar ice caps . Earth's land covers 29.2%, or 149 million km (58 million sq mi) of Earth's surface. The land surface includes many islands around the globe, but most of
1989-399: A large role in how people can feasibly navigate their environment. This can result in the isolation of certain communities from various resources and from each other. The placement of roads, highways, and sidewalks also determines what access people have to jobs and childcare close to home, especially in areas where most people do not own vehicles. Walkability directly influences community, so
2142-425: A liquid outer core that generates a magnetosphere capable of deflecting most of the destructive solar winds and cosmic radiation . Earth has a dynamic atmosphere , which sustains Earth's surface conditions and protects it from most meteoroids and UV-light at entry . It has a composition of primarily nitrogen and oxygen . Water vapor is widely present in the atmosphere, forming clouds that cover most of
2295-453: A pond from many other aquatic terrain features, such as stream pools and tide pools . Humans impact the water in different ways such as modifying rivers (through dams and stream channelization ), urbanization and deforestation . These impact lake levels, groundwater conditions, water pollution, thermal pollution, and marine pollution . Humans modify rivers by using direct channel manipulation. We build dams and reservoirs and manipulate
2448-419: A proper active lifestyle. Public health research has expanded the list of concerns associated with the built environment to include healthy food access , community gardens , mental health , physical health , walkability , and cycling mobility . Designing areas of cities with good public health is linked to creating opportunities for physical activity, community involvement, and equal opportunity within
2601-591: A shift is within the framework of the evolution of society. This shift caused the built aspect of these cities to grow and expand to meet the growing population needs. The pinnacle of city growth was during the Industrial Revolution due to the demand for jobs created by the rise in factories. Cities rapidly grew from the 1880s to the early 1900s within the United States. This demand led individuals to move from farms to cities which resulted in
2754-507: A variable amount of water vapor and suspensions of water droplets and ice crystals seen as clouds . Many natural substances may be present in tiny amounts in an unfiltered air sample, including dust , pollen and spores , sea spray , volcanic ash and meteoroids . Various industrial pollutants also may be present, such as chlorine (elementary or in compounds), fluorine compounds, elemental mercury , and sulphur compounds such as sulphur dioxide (SO 2 ). The ozone layer of
2907-514: Is rounded into an ellipsoid with a circumference of about 40,000 km. It is the densest planet in the Solar System . Of the four rocky planets , it is the largest and most massive. Earth is about eight light-minutes away from the Sun and orbits it , taking a year (about 365.25 days) to complete one revolution. Earth rotates around its own axis in slightly less than a day (in about 23 hours and 56 minutes). Earth's axis of rotation
3060-456: Is a chemically distinct silicate solid crust, which is underlain by a highly viscous solid mantle. The crust is separated from the mantle by the Mohorovičić discontinuity . The thickness of the crust varies from about 6 kilometres (3.7 mi) under the oceans to 30–50 km (19–31 mi) for the continents. The crust and the cold, rigid, top of the upper mantle are collectively known as
3213-483: Is approximately 9.8 m/s (32 ft/s ). Local differences in topography, geology, and deeper tectonic structure cause local and broad regional differences in Earth's gravitational field, known as gravity anomalies . The main part of Earth's magnetic field is generated in the core, the site of a dynamo process that converts the kinetic energy of thermally and compositionally driven convection into electrical and magnetic field energy. The field extends outwards from
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#17327722596923366-403: Is confined within a bed and stream banks . Streams play an important corridor role in connecting fragmented habitats and thus in conserving biodiversity . The study of streams and waterways in general is known as surface hydrology . A lake (from Latin lacus ) is a terrain feature , a body of water that is localized to the bottom of basin . A body of water is considered a lake when it
3519-529: Is contained in 3.45 billion-year-old Australian rocks showing fossils of microorganisms . During the Neoproterozoic , 1000 to 539 Ma , much of Earth might have been covered in ice. This hypothesis has been termed " Snowball Earth ", and it is of particular interest because it preceded the Cambrian explosion , when multicellular life forms significantly increased in complexity. Following
3672-792: Is enabled by Earth being an ocean world , the only one in the Solar System sustaining liquid surface water . Almost all of Earth's water is contained in its global ocean, covering 70.8% of Earth's crust . The remaining 29.2% of Earth's crust is land, most of which is located in the form of continental landmasses within Earth's land hemisphere . Most of Earth's land is at least somewhat humid and covered by vegetation , while large sheets of ice at Earth's polar deserts retain more water than Earth's groundwater , lakes, rivers and atmospheric water combined. Earth's crust consists of slowly moving tectonic plates , which interact to produce mountain ranges, volcanoes , and earthquakes. Earth has
3825-485: Is evidence to suggest that chronic disease can be reduced through healthy behaviors like a proper active lifestyle, good nutrition, and reduced exposure to toxins and pollutants. Yet, the built environment is not always designed to facilitate those healthy behaviors. Many urban environments, in particular suburbs, are automobile reliant, making it difficult or unreasonable to walk or bike to places. This condition not only adds to pollution, but can also make it hard to maintain
3978-457: Is farthest out from its center of mass at its equatorial bulge, the summit of the volcano Chimborazo in Ecuador (6,384.4 km or 3,967.1 mi) is its farthest point out. Parallel to the rigid land topography the ocean exhibits a more dynamic topography . To measure the local variation of Earth's topography, geodesy employs an idealized Earth producing a geoid shape. Such a shape
4131-790: Is from the Old English wildeornes , which in turn derives from wildeor meaning wild beast (wild + deor = beast, deer). From this point of view, it is the wildness of a place that makes it a wilderness. The mere presence or activity of people does not disqualify an area from being "wilderness". Many ecosystems that are, or have been, inhabited or influenced by activities of people may still be considered "wild". This way of looking at wilderness includes areas within which natural processes operate without very noticeable human interference. Wildlife includes all non- domesticated plants, animals and other organisms. Domesticating wild plant and animal species for human benefit has occurred many times all over
4284-516: Is gained if the ocean is idealized, covering Earth completely and without any perturbations such as tides and winds. The result is a smooth but irregular geoid surface, providing a mean sea level (MSL) as a reference level for topographic measurements. Earth's surface is the boundary between the atmosphere, and the solid Earth and oceans. Defined in this way, it has an area of about 510 million km (197 million sq mi). Earth can be divided into two hemispheres : by latitude into
4437-440: Is increasingly rare, wild nature (e.g., unmanaged forests , uncultivated grasslands , wildlife , wildflowers ) can be found in many locations previously inhabited by humans. Goals for the benefit of people and natural systems, commonly expressed by environmental scientists and environmentalists include: In some cultures the term environment is meaningless because there is no separation between people and what they view as
4590-519: Is inland, is not part of an ocean and is larger and deeper than a pond . Natural lakes on Earth are generally found in mountainous areas, rift zones and areas with ongoing or recent glaciation . Other lakes are found in endorheic basins or along the courses of mature rivers. In some parts of the world, there are many lakes because of chaotic drainage patterns left over from the last ice age . All lakes are temporary over geologic time scales, as they will slowly fill in with sediments or spill out of
4743-426: Is liquid under normal atmospheric pressure. Differences in the amount of captured energy between geographic regions (as with the equatorial region receiving more sunlight than the polar regions) drive atmospheric and ocean currents , producing a global climate system with different climate regions , and a range of weather phenomena such as precipitation , allowing components such as nitrogen to cycle . Earth
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4896-513: Is now slightly longer than it was during the 19th century due to tidal deceleration , each day varies between 0 and 2 ms longer than the mean solar day. Earth's rotation period relative to the fixed stars , called its stellar day by the International Earth Rotation and Reference Systems Service (IERS), is 86,164.0989 seconds of mean solar time ( UT1 ), or 23 56 4.0989 . Earth's rotation period relative to
5049-610: Is only what is built, that the forests, oceans, wildlife, and other aspects of nature are their own entity. The term built environment encompasses a broad range of categories, all of which have potential impacts. When looking at these potential impacts, the environment, as well as people, are heavily affected. The built environment can heavily impact the public's health. Historically, unsanitary conditions and overcrowding within cities and urban environments have led to infectious diseases and other health threats. Dating back to Georges-Eugene Haussmann 's comprehensive plans for urban Paris in
5202-622: Is rare, though the alternative spelling Gaia has become common due to the Gaia hypothesis , in which case its pronunciation is / ˈ ɡ aɪ . ə / rather than the more classical English / ˈ ɡ eɪ . ə / . There are a number of adjectives for the planet Earth. The word "earthly" is derived from "Earth". From the Latin Terra comes terran / ˈ t ɛr ə n / , terrestrial / t ə ˈ r ɛ s t r i ə l / , and (via French) terrene / t ə ˈ r iː n / , and from
5355-487: Is that it was formed by accretion from material loosed from Earth after a Mars -sized object with about 10% of Earth's mass, named Theia , collided with Earth. It hit Earth with a glancing blow and some of its mass merged with Earth. Between approximately 4.1 and 3.8 Ga , numerous asteroid impacts during the Late Heavy Bombardment caused significant changes to the greater surface environment of
5508-670: Is the application of science and technology to predict the state of the atmosphere for a future time and a given location. The atmosphere is a chaotic system , and small changes to one part of the system can grow to have large effects on the system as a whole. Human attempts to control the weather have occurred throughout human history, and there is evidence that civilized human activity such as agriculture and industry has inadvertently modified weather patterns. Evidence suggests that life on Earth has existed for about 3.7 billion years. All known life forms share fundamental molecular mechanisms, and based on these observations, theories on
5661-453: Is the basis for the astronomical unit (AU) and is equal to roughly 8.3 light minutes or 380 times Earth's distance to the Moon . Earth orbits the Sun every 365.2564 mean solar days , or one sidereal year . With an apparent movement of the Sun in Earth's sky at a rate of about 1°/day eastward, which is one apparent Sun or Moon diameter every 12 hours. Due to this motion, on average it takes 24 hours—a solar day—for Earth to complete
5814-425: Is the one originally developed by Wladimir Köppen . The Thornthwaite system , in use since 1948, uses evapotranspiration as well as temperature and precipitation information to study animal species diversity and the potential impacts of climate changes . Weather is a set of all the phenomena occurring in a given atmospheric area at a given time . Most weather phenomena occur in the troposphere , just below
5967-430: Is the outermost solid surface of the planet and is chemically, physically and mechanically different from underlying mantle . It has been generated greatly by igneous processes in which magma cools and solidifies to form solid rock. Beneath the lithosphere lies the mantle which is heated by the decay of radioactive elements . The mantle though solid is in a state of rheic convection . This convection process causes
6120-457: Is tied to that of the Sun. Over the next 1.1 billion years , solar luminosity will increase by 10%, and over the next 3.5 billion years by 40%. Earth's increasing surface temperature will accelerate the inorganic carbon cycle , possibly reducing CO 2 concentration to levels lethally low for current plants ( 10 ppm for C4 photosynthesis ) in approximately 100–900 million years . A lack of vegetation would result in
6273-455: Is tilted with respect to the perpendicular to its orbital plane around the Sun, producing seasons . Earth is orbited by one permanent natural satellite , the Moon , which orbits Earth at 384,400 km (1.28 light seconds) and is roughly a quarter as wide as Earth. The Moon's gravity helps stabilize Earth's axis, causes tides and gradually slows Earth's rotation . Tidal locking has made
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6426-486: The Arctic Ocean . A river is a natural watercourse , usually freshwater , flowing toward an ocean , a lake , a sea or another river. A few rivers simply flow into the ground and dry up completely without reaching another body of water. The water in a river is usually in a channel , made up of a stream bed between banks . In larger rivers there is often also a wider floodplain shaped by waters over-topping
6579-583: The Milky Way and orbits about 28,000 light-years from its center. It is about 20 light-years above the galactic plane in the Orion Arm . The axial tilt of Earth is approximately 23.439281° with the axis of its orbit plane, always pointing towards the Celestial Poles . Due to Earth's axial tilt, the amount of sunlight reaching any given point on the surface varies over the course of
6732-759: The Pacific , North American , Eurasian , African , Antarctic , Indo-Australian , and South American . Other notable plates include the Arabian Plate , the Caribbean Plate , the Nazca Plate off the west coast of South America and the Scotia Plate in the southern Atlantic Ocean. The Australian Plate fused with the Indian Plate between 50 and 55 Ma . The fastest-moving plates are
6885-712: The World Ocean or global ocean. The deep seabeds are more than half the Earth's surface, and are among the least-modified natural environments. The major oceanic divisions are defined in part by the continents , various archipelagos and other criteria, these divisions are : (in descending order of size) the Pacific Ocean , the Atlantic Ocean , the Indian Ocean , the Southern Ocean and
7038-413: The air and water . More precisely, we can consider the different aspects or components of an environment, and see that their degree of naturalness is not uniform. If, for instance, in an agricultural field, the mineralogic composition and the structure of its soil are similar to those of an undisturbed forest soil, but the structure is quite different. Earth science generally recognizes four spheres,
7191-419: The asthenosphere , the solid but less-viscous part of the upper mantle that can flow and move along with the plates. As the tectonic plates migrate, oceanic crust is subducted under the leading edges of the plates at convergent boundaries. At the same time, the upwelling of mantle material at divergent boundaries creates mid-ocean ridges. The combination of these processes recycles the oceanic crust back into
7344-415: The celestial equator , this is equivalent to an apparent diameter of the Sun or the Moon every two minutes; from Earth's surface, the apparent sizes of the Sun and the Moon are approximately the same. Earth orbits the Sun, making Earth the third-closest planet to the Sun and part of the inner Solar System . Earth's average orbital distance is about 150 million km (93 million mi), which
7497-407: The lithosphere , the hydrosphere , the atmosphere and the biosphere as correspondent to rocks , water , air and life respectively. Some scientists include as part of the spheres of the Earth, the cryosphere (corresponding to ice ) as a distinct portion of the hydrosphere, as well as the pedosphere (to soil ) as an active and intermixed sphere. Earth science (also known as geoscience,
7650-408: The mitigation of greenhouse gases that are causing climatic changes, on developing adaptative strategies to global warming, to assist humans, other animal, and plant species, ecosystems, regions and nations in adjusting to the effects of global warming . Some examples of recent collaboration to address climate change and global warming include: A significantly profound challenge is to identify
7803-408: The ocean floor form the top of Earth's crust , which together with parts of the upper mantle form Earth's lithosphere . Earth's crust may be divided into oceanic and continental crust. Beneath the ocean-floor sediments, the oceanic crust is predominantly basaltic , while the continental crust may include lower density materials such as granite , sediments and metamorphic rocks. Nearly 75% of
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#17327722596927956-430: The precessing or moving mean March equinox (when the Sun is at 90° on the equator), is 86,164.0905 seconds of mean solar time (UT1) (23 56 4.0905 ) . Thus the sidereal day is shorter than the stellar day by about 8.4 ms. Apart from meteors within the atmosphere and low-orbiting satellites, the main apparent motion of celestial bodies in Earth's sky is to the west at a rate of 15°/h = 15'/min. For bodies near
8109-413: The sphere of gravitational influence , of Earth is about 1.5 million km (930,000 mi) in radius. This is the maximum distance at which Earth's gravitational influence is stronger than that of the more distant Sun and planets. Objects must orbit Earth within this radius, or they can become unbound by the gravitational perturbation of the Sun. Earth, along with the Solar System, is situated in
8262-420: The stratosphere . Weather refers, generally, to day-to-day temperature and precipitation activity, whereas climate is the term for the average atmospheric conditions over longer periods of time. When used without qualification, "weather" is understood to be the weather of Earth. Weather occurs due to density (temperature and moisture) differences between one place and another. These differences can occur due to
8415-562: The surface of the Earth (an area of some 362 million square kilometers) is covered by ocean, a continuous body of water that is customarily divided into several principal oceans and smaller seas . More than half of this area is over 3,000 meters (9,800 ft) deep. Average oceanic salinity is around 35 parts per thousand (ppt) (3.5%), and nearly all seawater has a salinity in the range of 30 to 38 ppt. Though generally recognized as several separate oceans, these waters comprise one global, interconnected body of salt water often referred to as
8568-464: The "last ice age", covered large parts of the continents, to the middle latitudes, in ice and ended about 11,700 years ago. Chemical reactions led to the first self-replicating molecules about four billion years ago. A half billion years later, the last common ancestor of all current life arose. The evolution of photosynthesis allowed the Sun's energy to be harvested directly by life forms. The resultant molecular oxygen ( O 2 ) accumulated in
8721-511: The 1850s, concern for lack of air-flow and sanitary living conditions has inspired many strong city planning efforts. During the 19th century in particular, the connection between the built environment and public health became more apparent as life expectancy decreased and diseases, as well as epidemics, increased. Today, the built environment can expose individuals to pollutants or toxins that cause chronic diseases like asthma , diabetes , and coronary vascular disease, along with many others. There
8874-484: The Cambrian explosion, 535 Ma , there have been at least five major mass extinctions and many minor ones. Apart from the proposed current Holocene extinction event, the most recent was 66 Ma , when an asteroid impact triggered the extinction of non-avian dinosaurs and other large reptiles, but largely spared small animals such as insects, mammals , lizards and birds. Mammalian life has diversified over
9027-518: The Earth's atmosphere plays an important role in reducing the amount of ultraviolet (UV) radiation that reaches the surface. As DNA is readily damaged by UV light, this serves to protect life at the surface. The atmosphere also retains heat during the night, thereby reducing the daily temperature extremes. Earth's atmosphere can be divided into five main layers. These layers are mainly determined by whether temperature increases or decreases with altitude. From highest to lowest, these layers are: Within
9180-654: The Earth. Terra is also the name of the planet in some Romance languages , languages that evolved from Latin , like Italian and Portuguese , while in other Romance languages the word gave rise to names with slightly altered spellings, like the Spanish Tierra and the French Terre . The Latinate form Gæa or Gaea ( English: / ˈ dʒ iː . ə / ) of the Greek poetic name Gaia ( Γαῖα ; Ancient Greek : [ɡâi̯.a] or [ɡâj.ja] )
9333-533: The Latin Tellus comes tellurian / t ɛ ˈ l ʊər i ə n / and telluric . The oldest material found in the Solar System is dated to 4.5682 +0.0002 −0.0004 Ga (billion years) ago. By 4.54 ± 0.04 Ga the primordial Earth had formed. The bodies in the Solar System formed and evolved with the Sun. In theory, a solar nebula partitions a volume out of a molecular cloud by gravitational collapse, which begins to spin and flatten into
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#17327722596929486-758: The Moon always face Earth with the same side. Earth, like most other bodies in the Solar System, formed 4.5 billion years ago from gas and dust in the early Solar System . During the first billion years of Earth's history , the ocean formed and then life developed within it. Life spread globally and has been altering Earth's atmosphere and surface, leading to the Great Oxidation Event two billion years ago. Humans emerged 300,000 years ago in Africa and have spread across every continent on Earth. Humans depend on Earth's biosphere and natural resources for their survival, but have increasingly impacted
9639-426: The Moon and, by inference, to that of Earth. Earth's atmosphere and oceans were formed by volcanic activity and outgassing . Water vapor from these sources condensed into the oceans, augmented by water and ice from asteroids, protoplanets , and comets . Sufficient water to fill the oceans may have been on Earth since it formed. In this model, atmospheric greenhouse gases kept the oceans from freezing when
9792-458: The Solar System's planetary-sized objects, Earth is the object with the highest density . Earth's mass is approximately 5.97 × 10 kg ( 5.970 Yg ). It is composed mostly of iron (32.1% by mass ), oxygen (30.1%), silicon (15.1%), magnesium (13.9%), sulfur (2.9%), nickel (1.8%), calcium (1.5%), and aluminium (1.4%), with the remaining 1.2% consisting of trace amounts of other elements. Due to gravitational separation ,
9945-403: The Sun when the star reaches its maximum radius, otherwise, with tidal effects, it may enter the Sun's atmosphere and be vaporized. Earth has a rounded shape , through hydrostatic equilibrium , with an average diameter of 12,742 kilometres (7,918 mi), making it the fifth largest planetary sized and largest terrestrial object of the Solar System . Due to Earth's rotation it has
10098-415: The abiotic constituents of their biotope . A more significant number or variety of species or biological diversity of an ecosystem may contribute to greater resilience of an ecosystem because there are more species present at a location to respond to change and thus "absorb" or reduce its effects. This reduces the effect before the ecosystem's structure changes to a different state. This is not universally
10251-437: The assembly line production. With this new burst of personal transportation, new infrastructure was built to accommodate. Freeways were first built in 1956 to attempt to eliminate unsafe roads, traffic jams, and insufficient routes. The creation of freeways and interstate transportation systems opened up the possibility and ease of transportation outside a person's city. This allowed ease of travel not previously found and changed
10404-425: The atmosphere and due to interaction with ultraviolet solar radiation, formed a protective ozone layer ( O 3 ) in the upper atmosphere. The incorporation of smaller cells within larger ones resulted in the development of complex cells called eukaryotes . True multicellular organisms formed as cells within colonies became increasingly specialized. Aided by the absorption of harmful ultraviolet radiation by
10557-612: The basin containing them. A pond is a body of standing water , either natural or human-made, that is usually smaller than a lake . A wide variety of human-made bodies of water are classified as ponds, including water gardens designed for aesthetic ornamentation, fish ponds designed for commercial fish breeding and solar ponds designed to store thermal energy. Ponds and lakes are distinguished from streams by their current speed . While currents in streams are easily observed, ponds and lakes possess thermally driven micro-currents and moderate wind-driven currents. These features distinguish
10710-424: The biological manifestation of life is characterized by organization , metabolism , growth , adaptation , response to stimuli and reproduction . Life may also be said to be simply the characteristic state of organisms . In biology , the science of living organisms, "life" is the condition which distinguishes active organisms from inorganic matter , including the capacity for growth, functional activity and
10863-408: The built environment is already prominent, it pushes the boundaries of said built environment into new areas. While there are other factors that influence the built environment, like advancements in architecture or agriculture, transportation allowed for the spread and expansion of the built environment. Agriculture, the cultivation of soil to grow crops and animals to provide food as well as products,
11016-429: The built environment is typically used to describe the interdisciplinary field that encompasses the design, construction, management, and use of human-made physical influence as an interrelated whole. The concept also includes the relationship of these elements of the built environment with human activities over time—rather than a particular element in isolation or at a single moment in time, these aspects act together via
11169-504: The built environment often highlights the connection between physical space and social consequences. It impacts the environment and how society physically maneuvers and functions, as well as less tangible aspects of society such as socioeconomic inequity and health. Various aspects of the built environment contribute to scholarship on housing and segregation , physical activity, food access, climate change , and environmental racism . There are multiple different components that make up
11322-403: The built environment. Below are some prominent examples of what makes up the urban fabric: Buildings are used for a multitude of purposes: residential, commercial, community, institutional, and governmental. Building interiors are often designed to mediate external factors and provide space to conduct activities, whether that is to sleep, eat, work, etc. The structure of the building helps define
11475-411: The built environment. Urban forms that encourage physical activity and provide adequate public resources for involvement and upward mobility are proven to have far healthier populations than those that discourage such uses of the built environment. Features in the built environment present physical barriers which constitute the boundaries between neighborhoods . Roads and railways , for instance, play
11628-407: The case and there is no proven relationship between the species diversity of an ecosystem and its ability to provide goods and services on a sustainable level. The term ecosystem can also pertain to human-made environments, such as human ecosystems and human-influenced ecosystems. It can describe any situation where there is relationship between living organisms and their environment. Fewer areas on
11781-450: The center, the temperature may be up to 6,000 °C (10,830 °F), and the pressure could reach 360 GPa (52 million psi ). Because much of the heat is provided by radioactive decay, scientists postulate that early in Earth's history, before isotopes with short half-lives were depleted, Earth's heat production was much higher. At approximately 3 Gyr , twice the present-day heat would have been produced, increasing
11934-431: The channel. Flood plains may be very wide in relation to the size of the river channel. Rivers are a part of the hydrological cycle . Water within a river is generally collected from precipitation through surface runoff , groundwater recharge , springs and the release of water stored in glaciers and snowpacks. Small rivers may also be called by several other names, including stream , creek and brook. Their current
12087-454: The continental crust , particularly during the early stages of Earth's history. New continental crust forms as a result of plate tectonics , a process ultimately driven by the continuous loss of heat from Earth's interior. Over the period of hundreds of millions of years, tectonic forces have caused areas of continental crust to group together to form supercontinents that have subsequently broken apart. At approximately 750 Ma , one of
12240-616: The continental surfaces are covered by sedimentary rocks, although they form about 5% of the mass of the crust. Earth's surface topography comprises both the topography of the ocean surface , and the shape of Earth's land surface. The submarine terrain of the ocean floor has an average bathymetric depth of 4 km, and is as varied as the terrain above sea level. Earth's surface is continually being shaped by internal plate tectonic processes including earthquakes and volcanism ; by weathering and erosion driven by ice, water, wind and temperature; and by biological processes including
12393-423: The continual change preceding death. A diverse variety of living organisms (life forms) can be found in the biosphere on Earth, and properties common to these organisms—plants, animals , fungi , protists , archaea , and bacteria —are a carbon - and water-based cellular form with complex organization and heritable genetic information. Living organisms undergo metabolism , maintain homeostasis , possess
12546-419: The core are chaotic; the magnetic poles drift and periodically change alignment. This causes secular variation of the main field and field reversals at irregular intervals averaging a few times every million years. The most recent reversal occurred approximately 700,000 years ago. The extent of Earth's magnetic field in space defines the magnetosphere . Ions and electrons of the solar wind are deflected by
12699-527: The core is primarily composed of the denser elements: iron (88.8%), with smaller amounts of nickel (5.8%), sulfur (4.5%), and less than 1% trace elements. The most common rock constituents of the crust are oxides . Over 99% of the crust is composed of various oxides of eleven elements, principally oxides containing silicon (the silicate minerals ), aluminium, iron, calcium, magnesium, potassium, or sodium. The major heat-producing isotopes within Earth are potassium-40 , uranium-238 , and thorium-232 . At
12852-463: The core, through the mantle, and up to Earth's surface, where it is, approximately, a dipole . The poles of the dipole are located close to Earth's geographic poles. At the equator of the magnetic field, the magnetic-field strength at the surface is 3.05 × 10 T , with a magnetic dipole moment of 7.79 × 10 Am at epoch 2000, decreasing nearly 6% per century (although it still remains stronger than its long time average). The convection movements in
13005-539: The days shorter. Above the Arctic Circle and below the Antarctic Circle there is no daylight at all for part of the year, causing a polar night , and this night extends for several months at the poles themselves. These same latitudes also experience a midnight sun , where the sun remains visible all day. By astronomical convention, the four seasons can be determined by the solstices—the points in
13158-624: The direction of the rivers and water path. Dams can usefully create reservoirs and hydroelectric power. However, reservoirs and dams may negatively impact the environment and wildlife. Dams stop fish migration and the movement of organisms downstream. Urbanization affects the environment because of deforestation and changing lake levels, groundwater conditions, etc. Deforestation and urbanization go hand in hand. Deforestation may cause flooding, declining stream flow and changes in riverside vegetation. The changing vegetation occurs because when trees cannot get adequate water they start to deteriorate, leading to
13311-611: The earliest known supercontinents, Rodinia , began to break apart. The continents later recombined to form Pannotia at 600–540 Ma , then finally Pangaea , which also began to break apart at 180 Ma . The most recent pattern of ice ages began about 40 Ma , and then intensified during the Pleistocene about 3 Ma . High- and middle-latitude regions have since undergone repeated cycles of glaciation and thaw, repeating about every 21,000, 41,000 and 100,000 years. The Last Glacial Period , colloquially called
13464-455: The economic prosperity of a neighborhood, many formerly redlined areas continue to lack educational opportunities for residents and, thus, job and higher-income opportunities are limited. The built environment has a multitude of impacts on the planet, some of the most prominent effects are greenhouse gas emissions and Urban Heat Island Effect. The built environment expands along with factors like population and consumption which directly impact
13617-540: The environment, as well as quality of life. Urban Heat Islands are caused by reduction of natural landscape in favor of urban materials like asphalt, concrete, brick, etc. This change from natural landscape to urban materials is the epitome of the built environment and its expansion. Surface of the Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life . This
13770-408: The environment. Central to the ecosystem concept is the idea that living organisms are continually engaged in a highly interrelated set of relationships with every other element constituting the environment in which they exist. Eugene Odum , one of the founders of the science of ecology , stated: "Any unit that includes all of the organisms (i.e.: the "community") in a given area interacting with
13923-544: The equally large area of land under permafrost ) or deserts (33%). The pedosphere is the outermost layer of Earth's land surface and is composed of soil and subject to soil formation processes. Soil is crucial for land to be arable. Earth's total arable land is 10.7% of the land surface, with 1.3% being permanent cropland. Earth has an estimated 16.7 million km (6.4 million sq mi) of cropland and 33.5 million km (12.9 million sq mi) of pastureland. The land surface and
14076-481: The extinction of natural habitats, which in turn leads to a reduction in wildlife population. The most recent report from the Intergovernmental Panel on Climate Change (the group of the leading climate scientists in the world) concluded that the earth will warm anywhere from 2.7 to almost 11 degrees Fahrenheit (1.5 to 6 degrees Celsius) between 1990 and 2100. Efforts have been increasingly focused on
14229-416: The fabric of the built environment. New streets were being built within cities to accommodate cars as they became increasingly popular, railway lines were being built to connect areas not previously connected, for both public transportation as well as goods transportation. With these changes, the scope of a city began to expand outside its borders. The widespread use of cars and public transportation allowed for
14382-585: The five principal layers determined by temperature there are several layers determined by other properties. The dangers of global warming are being increasingly studied by a wide global consortium of scientists. These scientists are increasingly concerned about the potential long-term effects of global warming on our natural environment and on the planet. Of particular concern is how climate change and global warming caused by anthropogenic , or human-made releases of greenhouse gases , most notably carbon dioxide , can act interactively and have adverse effects upon
14535-419: The forests and wild-life parks that are held on a pedestal and are seemingly natural are in reality curated and allowed to exist for the enjoyment of the human experience. The planet has been irrevocably changed by human interaction. Wildlife has been hunted, harvested, brought to the brink of extinction, modified to fit human needs, the list goes on. This argument juxtaposes the argument that the built environment
14688-537: The geographical sciences or the Earth Sciences), is an all-embracing term for the sciences related to the planet Earth . There are four major disciplines in earth sciences, namely geography , geology , geophysics and geodesy . These major disciplines use physics , chemistry , biology , chronology and mathematics to build a qualitative and quantitative understanding of the principal areas or spheres of Earth. The Earth's crust or lithosphere ,
14841-638: The growth and decomposition of biomass into soil . Earth's mechanically rigid outer layer of Earth's crust and upper mantle , the lithosphere , is divided into tectonic plates . These plates are rigid segments that move relative to each other at one of three boundaries types: at convergent boundaries , two plates come together; at divergent boundaries , two plates are pulled apart; and at transform boundaries , two plates slide past one another laterally. Along these plate boundaries, earthquakes, volcanic activity , mountain-building , and oceanic trench formation can occur. The tectonic plates ride on top of
14994-404: The heat in Earth is lost through plate tectonics, by mantle upwelling associated with mid-ocean ridges . The final major mode of heat loss is through conduction through the lithosphere, the majority of which occurs under the oceans. The gravity of Earth is the acceleration that is imparted to objects due to the distribution of mass within Earth. Near Earth's surface, gravitational acceleration
15147-471: The idea that the built environment not only refers to that which is built, arranged, or curated, but also to what is managed, controlled, or allowed to continue. What is referred to as "nature" today can be seen as only a commodity that is placed into an environment that is constructed to fulfill the human will and desire. This commodity allows humans to enjoy the view and experience of nature without it inconveniencing their day-to-day life. It can be argued that
15300-430: The implementation of suburbs; the working individual was able to commute long distances to work everyday. Suburbs blurred the line of city "borders", the day-to-day life that may have originally been relegated to a pedestrian radius now encompassed a wide range of distances due to the use of cars and public transportation. This increased accessibility allowed for the continued expansion of the built environment. Currently,
15453-553: The industrial revolution was the City Beautiful movement . The City Beautiful movement emerged in the 1890s as a result of the disorder and unhealthy living conditions within industrial cities. The movement promoted improved circulation, civic centers, better sanitation, and public spaces. With these improvements, the goal was to improve the quality of life for those living in them, as well as make them more profitable. The City Beautiful movement, while declined in popularity over
15606-406: The land surface is taken by the four continental landmasses , which are (in descending order): Africa-Eurasia , America (landmass) , Antarctica , and Australia (landmass) . These landmasses are further broken down and grouped into the continents . The terrain of the land surface varies greatly and consists of mountains, deserts , plains , plateaus , and other landforms . The elevation of
15759-513: The land surface varies from a low point of −418 m (−1,371 ft) at the Dead Sea , to a maximum altitude of 8,848 m (29,029 ft) at the top of Mount Everest . The mean height of land above sea level is about 797 m (2,615 ft). Land can be covered by surface water , snow, ice, artificial structures or vegetation. Most of Earth's land hosts vegetation, but considerable amounts of land are ice sheets (10%, not including
15912-399: The lithosphere, which is divided into independently moving tectonic plates. Beneath the lithosphere is the asthenosphere , a relatively low-viscosity layer on which the lithosphere rides. Important changes in crystal structure within the mantle occur at 410 and 660 km (250 and 410 mi) below the surface, spanning a transition zone that separates the upper and lower mantle. Beneath
16065-408: The lithospheric plates to move, albeit slowly. The resulting process is known as plate tectonics . Volcanoes result primarily from the melting of subducted crust material or of rising mantle at mid-ocean ridges and mantle plumes . Most water is found in various kinds of natural body of water . An ocean is a major body of saline water and a component of the hydrosphere. Approximately 71% of
16218-410: The loss of oxygen in the atmosphere, making current animal life impossible. Due to the increased luminosity, Earth's mean temperature may reach 100 °C (212 °F) in 1.5 billion years, and all ocean water will evaporate and be lost to space, which may trigger a runaway greenhouse effect , within an estimated 1.6 to 3 billion years. Even if the Sun were stable, a fraction of the water in
16371-456: The lowercase when it is preceded by "the", such as "the atmosphere of the earth". It almost always appears in lowercase in colloquial expressions such as "what on earth are you doing?" The name Terra / ˈ t ɛr ə / occasionally is used in scientific writing and especially in science fiction to distinguish humanity's inhabited planet from others, while in poetry Tellus / ˈ t ɛ l ə s / has been used to denote personification of
16524-497: The magnetosphere. During magnetic storms and substorms , charged particles can be deflected from the outer magnetosphere and especially the magnetotail, directed along field lines into Earth's ionosphere , where atmospheric atoms can be excited and ionized, causing an aurora . Earth's rotation period relative to the Sun—its mean solar day—is 86,400 seconds of mean solar time ( 86,400.0025 SI seconds ). Because Earth's solar day
16677-409: The magnetosphere; solar wind pressure compresses the day-side of the magnetosphere, to about 10 Earth radii, and extends the night-side magnetosphere into a long tail. Because the velocity of the solar wind is greater than the speed at which waves propagate through the solar wind, a supersonic bow shock precedes the day-side magnetosphere within the solar wind. Charged particles are contained within
16830-483: The magnetosphere; the plasmasphere is defined by low-energy particles that essentially follow magnetic field lines as Earth rotates. The ring current is defined by medium-energy particles that drift relative to the geomagnetic field, but with paths that are still dominated by the magnetic field, and the Van Allen radiation belts are formed by high-energy particles whose motion is essentially random, but contained in
16983-417: The mantle, an extremely low viscosity liquid outer core lies above a solid inner core . Earth's inner core may be rotating at a slightly higher angular velocity than the remainder of the planet, advancing by 0.1–0.5° per year, although both somewhat higher and much lower rates have also been proposed. The radius of the inner core is about one-fifth of that of Earth. The density increases with depth. Among
17136-612: The mantle. Due to this recycling, most of the ocean floor is less than 100 Ma old. The oldest oceanic crust is located in the Western Pacific and is estimated to be 200 Ma old. By comparison, the oldest dated continental crust is 4,030 Ma , although zircons have been found preserved as clasts within Eoarchean sedimentary rocks that give ages up to 4,400 Ma , indicating that at least some continental crust existed at that time. The seven major plates are
17289-548: The modern oceans will descend to the mantle , due to reduced steam venting from mid-ocean ridges. The Sun will evolve to become a red giant in about 5 billion years . Models predict that the Sun will expand to roughly 1 AU (150 million km; 93 million mi), about 250 times its present radius. Earth's fate is less clear. As a red giant, the Sun will lose roughly 30% of its mass, so, without tidal effects, Earth will move to an orbit 1.7 AU (250 million km; 160 million mi) from
17442-399: The mother of Thor . Historically, "Earth" has been written in lowercase. Beginning with the use of Early Middle English , its definite sense as "the globe" was expressed as "the earth". By the era of Early Modern English , capitalization of nouns began to prevail , and the earth was also written the Earth , particularly when referenced along with other heavenly bodies. More recently,
17595-455: The multiplier effect. The field today draws upon areas such as economics , law, public policy , sociology , anthropology , public health, management , geography , design, engineering, technology, and environmental sustainability to create a large umbrella that is the built environment. There are some in modern academia who look at the built environment as all-encompassing, that there is no natural environment left. This argument comes from
17748-424: The name is sometimes simply given as Earth , by analogy with the names of the other planets , though "earth" and forms with "the earth" remain common. House styles now vary: Oxford spelling recognizes the lowercase form as the more common, with the capitalized form an acceptable variant. Another convention capitalizes "Earth" when appearing as a name, such as a description of the "Earth's atmosphere", but employs
17901-410: The natural environmental dynamics in contrast to environmental changes not within natural variances. A common solution is to adapt a static view neglecting natural variances to exist. Methodologically, this view could be defended when looking at processes which change slowly and short time series, while the problem arrives when fast processes turns essential in the object of the study. Climate looks at
18054-466: The natural world, or their surroundings. Specifically in the United States and Arabian countries many native cultures do not recognize the "environment", or see themselves as environmentalists. Built environment The term built environment refers to human-made conditions and is often used in architecture , landscape architecture , urban planning , public health , sociology , and anthropology , among others. These curated spaces provide
18207-422: The need to expand city infrastructure and created a boom in population size. This rapid growth in population in cities led to issues of noise, sanitation, health problems, traffic jams, pollution, compact living quarters, etc. In response to these issues, mass transit, trolleys, cable cars, and subways, were built and prioritized in an effort to improve the quality of the built environment. An example of this during
18360-425: The newly forming Sun had only 70% of its current luminosity . By 3.5 Ga , Earth's magnetic field was established, which helped prevent the atmosphere from being stripped away by the solar wind . As the molten outer layer of Earth cooled it formed the first solid crust , which is thought to have been mafic in composition. The first continental crust , which was more felsic in composition, formed by
18513-593: The ocean may have covered Earth completely. The world ocean is commonly divided into the Pacific Ocean, Atlantic Ocean, Indian Ocean, Antarctic or Southern Ocean , and Arctic Ocean, from largest to smallest. The ocean covers Earth's oceanic crust , with the shelf seas covering the shelves of the continental crust to a lesser extent. The oceanic crust forms large oceanic basins with features like abyssal plains , seamounts , submarine volcanoes , oceanic trenches , submarine canyons , oceanic plateaus , and
18666-670: The oceanic plates, with the Cocos Plate advancing at a rate of 75 mm/a (3.0 in/year) and the Pacific Plate moving 52–69 mm/a (2.0–2.7 in/year). At the other extreme, the slowest-moving plate is the South American Plate, progressing at a typical rate of 10.6 mm/a (0.42 in/year). Earth's interior, like that of the other terrestrial planets, is divided into layers by their chemical or physical ( rheological ) properties. The outer layer
18819-599: The orbit of maximum axial tilt toward or away from the Sun—and the equinoxes , when Earth's rotational axis is aligned with its orbital axis. In the Northern Hemisphere, winter solstice currently occurs around 21 December; summer solstice is near 21 June, spring equinox is around 20 March and autumnal equinox is about 22 or 23 September. In the Southern Hemisphere, the situation is reversed, with
18972-409: The origin of life attempt to find a mechanism explaining the formation of a primordial single cell organism from which all life originates. There are many different hypotheses regarding the path that might have been taken from simple organic molecules via pre-cellular life to protocells and metabolism. Although there is no universal agreement on the definition of life, scientists generally accept that
19125-652: The output of greenhouse gases. As cities and urban areas grow, the need for transportation and structures grows as well. In 2006, transportation accounted for 28% of total greenhouse gas emissions in the U.S. Building's design, location, orientation, and construction process heavily influence greenhouse gas emissions. Commercial, industrial, and residential buildings account for roughly 43% of U.S. CO 2 emissions in energy usage. In 2005, agricultural land use accounted for 10–12% of total human-caused greenhouse gas emissions worldwide. Urban heat islands are pockets of higher temperature areas, typically within cities, that effect
19278-649: The ozone layer, life colonized Earth's surface. Among the earliest fossil evidence for life is microbial mat fossils found in 3.48 billion-year-old sandstone in Western Australia , biogenic graphite found in 3.7 billion-year-old metasedimentary rocks in Western Greenland , and remains of biotic material found in 4.1 billion-year-old rocks in Western Australia. The earliest direct evidence of life on Earth
19431-474: The partial melting of this mafic crust. The presence of grains of the mineral zircon of Hadean age in Eoarchean sedimentary rocks suggests that at least some felsic crust existed as early as 4.4 Ga , only 140 Ma after Earth's formation. There are two main models of how this initial small volume of continental crust evolved to reach its current abundance: (1) a relatively steady growth up to
19584-501: The past 66 Mys , and several million years ago, an African ape species gained the ability to stand upright. This facilitated tool use and encouraged communication that provided the nutrition and stimulation needed for a larger brain, which led to the evolution of humans . The development of agriculture , and then civilization , led to humans having an influence on Earth and the nature and quantity of other life forms that continues to this day. Earth's expected long-term future
19737-501: The people who live and work there. George Galster and Patrick Sharkey refer to this variation in geographic context as "spatial opportunity structure", and claim that the built environment influences socioeconomic outcomes and general welfare. For instance, the history of redlining and housing segregation means that there is less green space in many Black and Hispanic neighborhoods. Access to parks and green space has been proven to be good for mental health which puts these communities at
19890-437: The physical environment so that a flow of energy leads to clearly defined trophic structure, biotic diversity, and material cycles (i.e.: exchange of materials between living and nonliving parts) within the system is an ecosystem." The human ecosystem concept is then grounded in the deconstruction of the human/nature dichotomy , and the emergent premise that all species are ecologically integrated with each other, as well as with
20043-478: The planet's environment . Humanity's current impact on Earth's climate and biosphere is unsustainable , threatening the livelihood of humans and many other forms of life, and causing widespread extinctions . The Modern English word Earth developed, via Middle English , from an Old English noun most often spelled eorðe . It has cognates in every Germanic language , and their ancestral root has been reconstructed as * erþō . In its earliest attestation,
20196-400: The planet, and has a major impact on the environment, both positive and negative. Wildlife can be found in all ecosystems. Deserts, rain forests, plains, and other areas—including the most developed urban sites—all have distinct forms of wildlife. While the term in popular culture usually refers to animals that are untouched by civilized human factors, most scientists agree that wildlife around
20349-414: The planet, its natural environment and humans' existence. It is clear the planet is warming, and warming rapidly. This is due to the greenhouse effect , which is caused by greenhouse gases, which trap heat inside the Earth's atmosphere because of their more complex molecular structure which allows them to vibrate and in turn trap heat and release it back towards the Earth. This warming is also responsible for
20502-400: The planet. The water vapor acts as a greenhouse gas and, together with other greenhouse gases in the atmosphere, particularly carbon dioxide (CO 2 ), creates the conditions for both liquid surface water and water vapor to persist via the capturing of energy from the Sun's light . This process maintains the current average surface temperature of 14.76 °C (58.57 °F), at which water
20655-421: The polar Northern and Southern hemispheres; or by longitude into the continental Eastern and Western hemispheres. Most of Earth's surface is ocean water: 70.8% or 361 million km (139 million sq mi). This vast pool of salty water is often called the world ocean , and makes Earth with its dynamic hydrosphere a water world or ocean world . Indeed, in Earth's early history
20808-495: The present day, which is supported by the radiometric dating of continental crust globally and (2) an initial rapid growth in the volume of continental crust during the Archean , forming the bulk of the continental crust that now exists, which is supported by isotopic evidence from hafnium in zircons and neodymium in sedimentary rocks. The two models and the data that support them can be reconciled by large-scale recycling of
20961-493: The rates of mantle convection and plate tectonics, and allowing the production of uncommon igneous rocks such as komatiites that are rarely formed today. The mean heat loss from Earth is 87 mW m , for a global heat loss of 4.42 × 10 W . A portion of the core's thermal energy is transported toward the crust by mantle plumes , a form of convection consisting of upwellings of higher-temperature rock. These plumes can produce hotspots and flood basalts . More of
21114-452: The setting for human activity and were created to fulfill human desires and needs. The term can refer to a plethora of components including the traditionally associated buildings, cities , public infrastructure, transportation , open space, as well as more conceptual components like farmlands , dammed rivers, wildlife management , and even domesticated animals . The built environment is made up of physical features. However, when studied,
21267-522: The shape of an ellipsoid , bulging at its Equator ; its diameter is 43 kilometres (27 mi) longer there than at its poles . Earth's shape also has local topographic variations; the largest local variations, like the Mariana Trench (10,925 metres or 35,843 feet below local sea level), shortens Earth's average radius by 0.17% and Mount Everest (8,848 metres or 29,029 feet above local sea level) lengthens it by 0.14%. Since Earth's surface
21420-414: The space around it, giving form to how individuals move through the space around the building. Public infrastructure covers a variety of things like roads, highways, pedestrian circulation, public transportation, and parks. Roads and highways are an important feature of the built environment that enable vehicles to access a wide range of urban and non urban spaces. They are often compared to veins within
21573-493: The statistics of temperature , humidity , atmospheric pressure , wind , rainfall , atmospheric particle count and other meteorological elements in a given region over long periods of time. Weather , on the other hand, is the present condition of these same elements over periods up to two weeks. Climates can be classified according to the average and typical ranges of different variables, most commonly temperature and precipitation. The most commonly used classification scheme
21726-434: The sun angle at any particular spot, which varies by latitude from the tropics. The strong temperature contrast between polar and tropical air gives rise to the jet stream . Weather systems in the mid-latitudes , such as extratropical cyclones , are caused by instabilities of the jet stream flow. Because the Earth's axis is tilted relative to its orbital plane, sunlight is incident at different angles at different times of
21879-406: The supposedly "unbuilt" environment. The term describes a wide range of fields that form an interdisciplinary concept that has been accepted as an idea since classical antiquity and potentially before. Through the study of anthropology , the progression of the built environment into what it is today has been able to be examined. When people are able to travel outside of urban centers and areas where
22032-773: The surface of the earth today exist free from human contact, although some genuine wilderness areas continue to exist without any forms of human intervention. Global biogeochemical cycles are critical to life, most notably those of water , oxygen , carbon , nitrogen and phosphorus . Wilderness is generally defined as a natural environment on Earth that has not been significantly modified by human activity. The WILD Foundation goes into more detail, defining wilderness as: "The most intact, undisturbed wild natural areas left on our planet – those last truly wild places that humans do not control and have not developed with roads, pipelines or other industrial infrastructure." Wilderness areas and protected parks are considered important for
22185-419: The survival of certain species , ecological studies, conservation , solitude, and recreation . Wilderness is deeply valued for cultural, spiritual, moral , and aesthetic reasons. Some nature writers believe wilderness areas are vital for the human spirit and creativity. The word, "wilderness", derives from the notion of wildness ; in other words that which is not controllable by humans. The word etymology
22338-403: The way a neighborhood is built affects the outcomes and opportunities of the community that lives there. Even less physically imposing features, such as architectural design , can distinguish the boundaries between communities and decrease movement across neighborhood lines. The segregation of communities is significant because the qualities of any given space directly impact the wellbeing of
22491-461: The word eorðe was used to translate the many senses of Latin terra and Greek γῆ gē : the ground, its soil , dry land, the human world, the surface of the world (including the sea), and the globe itself. As with Roman Terra /Tellūs and Greek Gaia , Earth may have been a personified goddess in Germanic paganism : late Norse mythology included Jörð ("Earth"), a giantess often given as
22644-411: The world is (now) impacted by human activities. It is the common understanding of natural environment that underlies environmentalism — a broad political , social and philosophical movement that advocates various actions and policies in the interest of protecting what nature remains in the natural environment, or restoring or expanding the role of nature in this environment. While true wilderness
22797-465: The year. On the Earth's surface, temperatures usually range ±40 °C (100 °F to −40 °F) annually. Over thousands of years, changes in the Earth's orbit have affected the amount and distribution of solar energy received by the Earth and influenced long-term climate. Surface temperature differences in turn cause pressure differences. Higher altitudes are cooler than lower altitudes due to differences in compressional heating. Weather forecasting
22950-620: The year. This causes the seasonal change in climate, with summer in the Northern Hemisphere occurring when the Tropic of Cancer is facing the Sun, and in the Southern Hemisphere when the Tropic of Capricorn faces the Sun. In each instance, winter occurs simultaneously in the opposite hemisphere. During the summer, the day lasts longer, and the Sun climbs higher in the sky. In winter, the climate becomes cooler and
23103-426: The years, provided a range of urban reforms. The movement highlighted city planning, civic education, public transportation, and municipal housekeeping. The invention of cars, as well as train usage, became more accessible to the general masses due to the advancements in the steel, chemicals, and fuel generated production. In the 1920s, cars became more accessible to the general public due to Henry Ford's advances in
23256-735: Was fertile and good for agricultural use. In these early communities, a priority was to ensure basic needs were being met. The built environment, while not as extensive as it is today, was beginning to be cultivated with the implementation of buildings, paths, farm land, domestication of animals and plants, etc. Over the next several thousand years, these smaller cities and villages grew into larger ones where trade, culture, education, and economics were driving factors. As cities began to grow, they needed to accommodate more people, as well as shifted from focusing on meeting survival needs to prioritizing comfort and desires – there are still many individuals today who do not have their basic needs met and this idea of
23409-505: Was first developed about 12,000 years ago. This switch, also called the Neolithic Revolution , was the beginning of favoring permanent settlements and altering the land to grow crops and farm animals. This can be thought of as the start of the built environment, the first attempt to make permanent changes to the surrounding environment for human needs. The first appearance of cities was around 7500 BCE, dotted along where land
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