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132-721: The Anthropocene is a now rejected proposal for the name of a geological epoch that would follow the Holocene , dating from the commencement of significant human impact on Earth up to the present day. It was rejected in 2024 by the International Commission on Stratigraphy in terms of being a defined geologic period . The impacts of humans affect Earth's oceans , geology , geomorphology , landscape , limnology , hydrology , ecosystems and climate . The effects of human activities on Earth can be seen for example in biodiversity loss and climate change . Various start dates for

264-727: A geological epoch distinct from the Holocene. The Anthropocene Working Group met in Oslo in April 2016 to consolidate evidence supporting the argument for the Anthropocene as a true geologic epoch. Evidence was evaluated and the group voted to recommend Anthropocene as the new geological epoch in August 2016. In April 2019, the Anthropocene Working Group (AWG) announced that they would vote on

396-682: A chemical compound exists than previously thought possible. This will stimulate new modeling and laboratory studies which will increase our scientific understanding to a level where we can explain the observations. Field observations of chemical systems are essential to understanding atmospheric processes and determining the accuracy of models. Atmospheric chemistry measurements can be long term to observe continuous trends or short term to observe smaller variations. Measurements can be made with observatories, satellites, and surface observations . Routine observations of chemical composition show changes in atmospheric composition over time. Observatories such as

528-620: A constituent body of the International Union of Geological Sciences (IUGS), whose primary objective is to precisely define global chronostratigraphic units of the International Chronostratigraphic Chart (ICC) that are used to define divisions of geologic time. The chronostratigraphic divisions are in turn used to define geochronologic units. The geologic time scale is a way of representing deep time based on events that have occurred throughout Earth's history ,

660-432: A depositional regime, engineered structures will tend to be buried and preserved, along with litter and debris. Litter and debris thrown from boats or carried by rivers and creeks will accumulate in the marine environment, particularly in coastal areas, but also in mid-ocean garbage patches . Such human-created artifacts preserved in stratigraphy are known as "technofossils". Changes in biodiversity will also be reflected in

792-644: A dramatic rate. The Atomic Age also started around the mid-20th century, when the risks of nuclear wars , nuclear terrorism and nuclear accidents increased. Twelve candidate sites were selected for the GSSP; the sediments of Crawford Lake , Canada were finally proposed, in July 2023, to mark the lower boundary of the Anthropocene, starting with the Crawfordian stage/age in 1950. In March 2024, after 15 years of deliberation,

924-480: A formal proposal to the International Commission on Stratigraphy , to continue the process started at the 2016 meeting. In May 2019, 29 members of the 34 person AWG panel voted in favour of an official proposal to be made by 2021. The AWG also voted with 29 votes in favour of a starting date in the mid 20th century. Ten candidate sites for a Global boundary Stratotype Section and Point have been identified, one of which will be chosen to be included in

1056-522: A formal proposal to the ICS for the establishment of the Anthropocene Series/Epoch. Nevertheless, the definition of the Anthropocene as a geologic time period rather than a geologic event remains controversial and difficult. An international working group of the ICS on pre-Cryogenian chronostratigraphic subdivision have outlined a template to improve the pre-Cryogenian geologic time scale based on

1188-602: A formal unit of the Geologic Time Scale, Anthropocene will nevertheless continue to be used not only by Earth and environmental scientists, but also by social scientists, politicians and economists, as well as by the public at large. It will remain an invaluable descriptor of human impact on the Earth system." An early concept for the Anthropocene was the Noosphere by Vladimir Vernadsky , who in 1938 wrote of "scientific thought as

1320-604: A geological force". Scientists in the Soviet Union appear to have used the term Anthropocene as early as the 1960s to refer to the Quaternary , the most recent geological period . Ecologist Eugene F. Stoermer subsequently used Anthropocene with a different sense in the 1980s and the term was widely popularised in 2000 by atmospheric chemist Paul J. Crutzen , who regards the influence of human behavior on Earth's atmosphere in recent centuries as so significant as to constitute

1452-643: A global picture of air pollution and chemistry. Surface observations have the advantage that they provide long term records at high time resolution but are limited in the vertical and horizontal space they provide observations from. Some surface based instruments e.g. LIDAR can provide concentration profiles of chemical compounds and aerosols but are still restricted in the horizontal region they can cover. Many observations are available online in Atmospheric Chemistry Observational Databases Laboratory studies help understand

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1584-429: A key marker the group chose to place the start of the Anthropocene in the 1950s, along with other elevated markers including carbon particles and nitrates from the burning of fossil fuels and widespread application of chemical fertilizers respectively. Had it been approved, the official declaration of the new Anthropocene epoch would have taken place in August 2024, and its first age may have been named Crawfordian after

1716-580: A known geological context. The geological history of Mars has been divided into two alternate time scales. The first time scale for Mars was developed by studying the impact crater densities on the Martian surface. Through this method four periods have been defined, the Pre-Noachian (~4,500–4,100 Ma), Noachian (~4,100–3,700 Ma), Hesperian (~3,700–3,000 Ma), and Amazonian (~3,000 Ma to present). Atmospheric chemistry The composition and chemistry of

1848-617: A machine-readable Resource Description Framework / Web Ontology Language representation of the time scale, which is available through the Commission for the Management and Application of Geoscience Information GeoSciML project as a service and at a SPARQL end-point. Some other planets and satellites in the Solar System have sufficiently rigid structures to have preserved records of their own histories, for example, Venus , Mars and

1980-427: A new geological epoch. The pressures we exert on the planet have become so great that scientists are considering whether the Earth has entered an entirely new geological epoch: the Anthropocene, or the age of humans. It means that we are the first people to live in an age defined by human choice, in which the dominant risk to our survival is ourselves. — Achim Steiner , UNDP Administrator The term Anthropocene

2112-419: A precise date of start to highly diachronous processes of human-influenced Earth system change. The argument indicated that finding a single GSSP would be impractical, given human-induced changes in the Earth system occurred at different periods, in different places, and spread under different rates. Under this model, the Anthropocene would have many events marking human-induced impacts on the planet, including

2244-409: A range of activities around the world that seek to ameliorate these issues or prevent them from happening. Changes in drainage patterns traceable to human activity will persist over geologic time in large parts of the continents where the geologic regime is erosional. This involves, for example, the paths of roads and highways defined by their grading and drainage control. Direct changes to the form of

2376-529: A rock that cuts across another rock must be younger than the rock it cuts across. The law of included fragments that states small fragments of one type of rock that are embedded in a second type of rock must have formed first, and were included when the second rock was forming. The relationships of unconformities which are geologic features representing a gap in the geologic record. Unconformities are formed during periods of erosion or non-deposition, indicating non-continuous sediment deposition. Observing

2508-419: A specific interval of geologic time, and only this time span. Eonothem, erathem, system, series, subseries, stage, and substage are the hierarchical chronostratigraphic units. A geochronologic unit is a subdivision of geologic time. It is a numeric representation of an intangible property (time). These units are arranged in a hierarchy: eon, era, period, epoch, subepoch, age, and subage. Geochronology

2640-532: A system/series (early/middle/late); however, the International Commission on Stratigraphy advocates for all new series and subseries to be named for a geographic feature in the vicinity of its stratotype or type locality . The name of stages should also be derived from a geographic feature in the locality of its stratotype or type locality. Informally, the time before the Cambrian is often referred to as

2772-643: A time span of about 4.54 ± 0.05 Ga (4.54 billion years). It chronologically organises strata, and subsequently time, by observing fundamental changes in stratigraphy that correspond to major geological or paleontological events. For example, the Cretaceous–Paleogene extinction event , marks the lower boundary of the Paleogene System/Period and thus the boundary between the Cretaceous and Paleogene systems/periods. For divisions prior to

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2904-525: A variety of physical processes such as wind, convection, and atmospheric mixing. They also provide more realistic depictions of transportation and mixing. However, computational limits often simply chemical reactions and typically include fewer chemical reactions than box models. The trade-off between the two approaches lies in resolution and complexity. To simplify the creation of these complex models, some researchers use automatic code generators like Autochem or Kinetic PreProcessor . These tools help automate

3036-458: A wider sense, correlating strata across national and continental boundaries based on their similarity to each other. Many of the names below erathem/era rank in use on the modern ICC/GTS were determined during the early to mid-19th century. During the 19th century, the debate regarding Earth's age was renewed, with geologists estimating ages based on denudation rates and sedimentary thicknesses or ocean chemistry, and physicists determining ages for

3168-469: Is a decrease or disappearance of species in a specific area. Biodiversity loss means that there is a reduction in biological diversity in a given area. The decrease can be temporary or permanent. It is temporary if the damage that led to the loss is reversible in time, for example through ecological restoration . If this is not possible, then the decrease is permanent. The cause of most of the biodiversity loss is, generally speaking, human activities that push

3300-437: Is a representation of time based on the rock record of Earth . It is a system of chronological dating that uses chronostratigraphy (the process of relating strata to time) and geochronology (a scientific branch of geology that aims to determine the age of rocks). It is used primarily by Earth scientists (including geologists , paleontologists , geophysicists , geochemists , and paleoclimatologists ) to describe

3432-543: Is an internationally agreed-upon reference point on a stratigraphic section that defines the lower boundaries of stages on the geologic time scale. (Recently this has been used to define the base of a system) A Global Standard Stratigraphic Age (GSSA) is a numeric-only, chronologic reference point used to define the base of geochronologic units prior to the Cryogenian. These points are arbitrarily defined. They are used where GSSPs have not yet been established. Research

3564-508: Is because the widely-adopted 1950 start date was found to be prone to recency bias. It also overshadowed earlier examples of human impacts, many of which happened in different parts of the world at different times. Although the proposal could be raised again, this would require the entire process of debate to start from the beginning. The results of the vote were officially confirmed by the IUGS and upheld as definitive later that month. Crutzen proposed

3696-500: Is chemistry and climate , such as how changing climate affects the recovery of the ozone hole and vice versa but also interaction of the composition of the atmosphere with the oceans and terrestrial ecosystems . Observations, lab measurements, and modeling are the three central elements in atmospheric chemistry. Progress in atmospheric chemistry is often driven by the interactions between these components and they form an integrated whole. For example, observations may tell us that more of

3828-861: Is currently underway. A 2022 study published in Frontiers in Ecology and the Environment , which surveyed more than 3,000 experts, states that the extinction crisis could be worse than previously thought, and estimates that roughly 30% of species "have been globally threatened or driven extinct since the year 1500." According to a 2023 study published in Biological Reviews some 48% of 70,000 monitored species are experiencing population declines from human activity, whereas only 3% have increasing populations. Biodiversity loss happens when plant or animal species disappear completely from Earth ( extinction ) or when there

3960-439: Is divided into chronostratigraphic units and their corresponding geochronologic units. The subdivisions Early and Late are used as the geochronologic equivalents of the chronostratigraphic Lower and Upper , e.g., Early Triassic Period (geochronologic unit) is used in place of Lower Triassic System (chronostratigraphic unit). Rocks representing a given chronostratigraphic unit are that chronostratigraphic unit, and

4092-436: Is increasing atmospheric carbon dioxide (CO 2 ) content. This signal in the Earth's climate system is especially significant because it is occurring much faster, and to a greater extent, than previously. Most of this increase is due to the combustion of fossil fuels such as coal, oil , and gas . Effects of climate change are well documented and growing for Earth's natural environment and human societies. Changes to

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4224-497: Is informally used in scientific contexts. The Geological Society of America entitled its 2011 annual meeting: Archean to Anthropocene: The past is the key to the future . The new epoch has no agreed start-date, but one proposal, based on atmospheric evidence, is to fix the start with the Industrial Revolution c. 1780, with the invention of the steam engine . Other scientists link the new term to earlier events, such as

4356-556: Is less frequent) remains unchanged. For example, in early 2022, the boundary between the Ediacaran and Cambrian periods (geochronologic units) was revised from 541 Ma to 538.8 Ma but the rock definition of the boundary (GSSP) at the base of the Cambrian, and thus the boundary between the Ediacaran and Cambrian systems (chronostratigraphic units) has not been changed; rather, the absolute age has merely been refined. Chronostratigraphy

4488-574: Is now firmly established as the sixth factor of soil formation. Humanity affects pedogenesis directly by, for example, land levelling, trenching and embankment building, landscape-scale control of fire by early humans , organic matter enrichment from additions of manure or other waste, organic matter impoverishment due to continued cultivation and compaction from overgrazing . Human activity also affects pedogenesis indirectly by drift of eroded materials or pollutants. Anthropogenic soils are those markedly affected by human activities, such as repeated ploughing,

4620-484: Is ongoing to define GSSPs for the base of all units that are currently defined by GSSAs. The standard international units of the geologic time scale are published by the International Commission on Stratigraphy on the International Chronostratigraphic Chart; however, regional terms are still in use in some areas. The numeric values on the International Chronostratigrahpic Chart are represented by

4752-457: Is still a useful concept. The principle of lateral continuity that states layers of sediments extend laterally in all directions until either thinning out or being cut off by a different rock layer, i.e. they are laterally continuous. Layers do not extend indefinitely; their limits are controlled by the amount and type of sediment in a sedimentary basin , and the geometry of that basin. The principle of cross-cutting relationships that states

4884-502: Is the element of stratigraphy that deals with the relation between rock bodies and the relative measurement of geological time. It is the process where distinct strata between defined stratigraphic horizons are assigned to represent a relative interval of geologic time. A chronostratigraphic unit is a body of rock, layered or unlayered, that is defined between specified stratigraphic horizons which represent specified intervals of geologic time. They include all rocks representative of

5016-405: Is the scientific branch of geology that aims to determine the age of rocks, fossils, and sediments either through absolute (e.g., radiometric dating ) or relative means (e.g., stratigraphic position , paleomagnetism , stable isotope ratios ). Geochronometry is the field of geochronology that numerically quantifies geologic time. A Global Boundary Stratotype Section and Point (GSSP)

5148-476: The Anthropocene is a proposed epoch/series for the most recent time in Earth's history. While still informal, it is a widely used term to denote the present geologic time interval, in which many conditions and processes on Earth are profoundly altered by human impact. As of April 2022 the Anthropocene has not been ratified by the ICS; however, in May 2019 the Anthropocene Working Group voted in favour of submitting

5280-529: The Brothers of Purity , who wrote on the processes of stratification over the passage of time in their treatises . Their work likely inspired that of the 11th-century Persian polymath Avicenna (Ibn Sînâ, 980–1037) who wrote in The Book of Healing (1027) on the concept of stratification and superposition, pre-dating Nicolas Steno by more than six centuries. Avicenna also recognised fossils as "petrifications of

5412-592: The Cryogenian , arbitrary numeric boundary definitions ( Global Standard Stratigraphic Ages , GSSAs) are used to divide geologic time. Proposals have been made to better reconcile these divisions with the rock record. Historically, regional geologic time scales were used due to the litho- and biostratigraphic differences around the world in time equivalent rocks. The ICS has long worked to reconcile conflicting terminology by standardising globally significant and identifiable stratigraphic horizons that can be used to define

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5544-588: The International Union of Geological Sciences (IUGS) rejected the Anthropocene Epoch proposal for inclusion in the Geologic Time Scale . The Anthropocene Working Group (AWG) of the Subcommission on Quaternary Stratigraphy (SQS) of the ICS voted in April 2016 to proceed towards a formal golden spike (GSSP) proposal to define the Anthropocene epoch in the geologic time scale . The group presented

5676-712: The Mauna Loa and mobile platforms such as aircraft ships and balloons (e.g. the UK's Facility for Airborne Atmospheric Measurements ) study chemical compositions and weather dynamics. An application of long term observations is the Keeling Curve - a series of measurements from 1958 to today which show a steady rise in the concentration of carbon dioxide (see also ongoing measurements of atmospheric CO 2 ). Observations of atmospheric composition are increasingly made by satellites with important instruments such as GOME and MOPITT giving

5808-530: The Precambrian or pre-Cambrian (Supereon). While a modern geological time scale was not formulated until 1911 by Arthur Holmes , the broader concept that rocks and time are related can be traced back to (at least) the philosophers of Ancient Greece . Xenophanes of Colophon (c. 570–487  BCE ) observed rock beds with fossils of shells located above the sea-level, viewed them as once living organisms, and used this to imply an unstable relationship in which

5940-544: The Upper Fremont Glacier in Wyoming, there is a layer of chlorine present in ice cores from 1960's atomic weapon testing programs, as well as a layer of mercury associated with coal plants in the 1980s. From the late 1940s, nuclear tests have led to local nuclear fallout and severe contamination of test sites both on land and in the surrounding marine environment. Some of the radionuclides that were released during

6072-418: The climate system include an overall warming trend , changes to precipitation patterns , and more extreme weather . As the climate changes it impacts the natural environment with effects such as more intense forest fires , thawing permafrost , and desertification . These changes impact ecosystems and societies, and can become irreversible once tipping points are crossed. Climate activists are engaged in

6204-581: The first atomic bomb in 1945 or the Partial Nuclear Test Ban Treaty in 1963). The name Anthropocene is a combination of anthropo- from the Ancient Greek ἄνθρωπος ( ánthropos ) meaning 'human' and -cene from καινός ( kainós ) meaning 'new' or 'recent'. As early as 1873, the Italian geologist Antonio Stoppani acknowledged the increasing power and effect of humanity on

6336-646: The mass extinction of large vertebrates , the development of early farming , land clearance in the Americas, global-scale industrial transformation during the Industrial Revolution , and the start of the Atomic Age . The authors are members of the AWG who had voted against the official proposal of a starting date in the mid-20th century, and sought to reconcile some of the previous models (including Ruddiman and Maslin proposals). They cited Crutzen 's original concept, arguing that

6468-620: The planetary boundaries too far. These activities include habitat destruction (for example deforestation ) and land use intensification (for example monoculture farming). Further problem areas are air and water pollution (including nutrient pollution ), over-exploitation , invasive species and climate change . Studies of urban evolution give an indication of how species may respond to stressors such as temperature change and toxicity. Species display varying abilities to respond to altered environments through both phenotypic plasticity and genetic evolution . Researchers have documented

6600-444: The 18th century, as chemists such as Joseph Priestley , Antoine Lavoisier and Henry Cavendish made the first measurements of the composition of the atmosphere. In the late 19th and early 20th centuries, researchers shifted their interest towards trace constituents with very low concentrations. One particularly important discovery for atmospheric chemistry was the discovery of ozone by Christian Friedrich Schönbein in 1840. In

6732-584: The 1995 Nobel Prize in Chemistry award shared between Paul Crutzen , Mario Molina and Frank Sherwood Rowland . In the 21st century the focus is now shifting again. Atmospheric chemistry is increasingly studied as one part of the Earth system . Instead of concentrating on atmospheric chemistry in isolation the focus is now on seeing it as one part of a single system with the rest of the atmosphere , biosphere and geosphere . An especially important driver for this link

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6864-472: The 19th century and further since. Rapid economic growth is considered a primary driver of the contemporary displacement and eradication of other species. According to the 2021 Economics of Biodiversity review, written by Partha Dasgupta and published by the UK government, "biodiversity is declining faster than at any time in human history." A 2022 scientific review published in Biological Reviews confirms that an anthropogenic sixth mass extinction event

6996-520: The 20th century atmospheric science moved on from studying the composition of air to a consideration of how the concentrations of trace gasses in the atmosphere have changed over time and the chemical processes which create and destroy compounds in the air. Two particularly important examples of this were the explanation by Sydney Chapman and Gordon Dobson of how the ozone layer is created and maintained, and Arie Jan Haagen-Smit ’s explanation of photochemical smog . Further studies on ozone issues led to

7128-465: The Anthropocene Epoch proposal of the AWG was voted down by a wide margin by the SQS, owing largely to its shallow sedimentary record and extremely recent proposed start date. The ICS and the IUGS later formally confirmed, by a near unanimous vote, the rejection of the AWG's Anthropocene Epoch proposal for inclusion in the Geologic Time Scale. The IUGS statement on the rejection concluded: "Despite its rejection as

7260-471: The Anthropocene have been proposed, ranging from the beginning of the Neolithic Revolution (12,000–15,000 years ago), to as recently as the 1960s. The biologist Eugene F. Stoermer is credited with first coining and using the term anthropocene informally in the 1980s; Paul J. Crutzen re-invented and popularized the term. However, in 2024 the International Commission on Stratigraphy (ICS) and

7392-517: The Anthropocene is much better and more usefully conceived of as an unfolding geological event, like other major transformations in Earth's history such as the Great Oxidation Event . In July 2023, the AWG chose Crawford Lake in Ontario, Canada as a site representing the beginning of the proposed new epoch. The sediment in that lake shows a spike in levels of plutonium from hydrogen bomb tests,

7524-644: The Anthropocene should be extended back many thousand years"; this would make the Anthropocene essentially synonymous with the current term, Holocene . In 2008, the Stratigraphy Commission of the Geological Society of London considered a proposal to make the Anthropocene a formal unit of geological epoch divisions. A majority of the commission decided the proposal had merit and should be examined further. Independent working groups of scientists from various geological societies began to determine whether

7656-606: The Anthropocene will be formally accepted into the Geological Time Scale . In January 2015, 26 of the 38 members of the International Anthropocene Working Group published a paper suggesting the Trinity test on 16 July 1945 as the starting point of the proposed new epoch. However, a significant minority supported one of several alternative dates. A March 2015 report suggested either 1610 or 1964 as

7788-668: The Commission on Stratigraphy (applied in 1965) to become a member commission of IUGS led to the founding of the ICS. One of the primary objectives of the ICS is "the establishment, publication and revision of the ICS International Chronostratigraphic Chart which is the standard, reference global Geological Time Scale to include the ratified Commission decisions". Following on from Holmes, several A Geological Time Scale books were published in 1982, 1989, 2004, 2008, 2012, 2016, and 2020. However, since 2013,

7920-546: The Earth System has departed from its Holocene state since c. 1950 CE, forcing abrupt physical, chemical and biological changes to the Earth's stratigraphic record that can be used to justify the proposal for naming a new epoch—the Anthropocene." A December 2020 study published in Nature found that the total anthropogenic mass, or human-made materials, outweighs all the biomass on earth, and highlighted that "this quantification of

8052-464: The Earth's Moon . Dominantly fluid planets, such as the giant planets , do not comparably preserve their history. Apart from the Late Heavy Bombardment , events on other planets probably had little direct influence on the Earth, and events on Earth had correspondingly little effect on those planets. Construction of a time scale that links the planets is, therefore, of only limited relevance to

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8184-624: The Earth's atmosphere is important for several reasons, but primarily because of the interactions between the atmosphere and living organisms . Natural processes such as volcano emissions, lightning and bombardment by solar particles from corona changes the composition of the Earth's atmosphere. It has also been changed by human activity and some of these changes are harmful to human health, crops and ecosystems. Examples of problems addressed in atmospheric chemistry include acid rain , ozone depletion , photochemical smog , greenhouse gasses and global warming . Atmospheric chemists work to understand

8316-482: The Earth's surface by human activities ( quarrying and landscaping , for example) also record human impacts. It has been suggested that the deposition of calthemite formations exemplify a natural process which has not previously occurred prior to the human modification of the Earth's surface, and which therefore represents a unique process of the Anthropocene. Calthemite is a secondary deposit, derived from concrete, lime , mortar or other calcareous material outside

8448-664: The Earth's systems and referred to an 'anthropozoic era'. The human impact on biodiversity forms one of the primary attributes of the Anthropocene. Humankind has entered what is sometimes called the Earth's sixth major extinction. Most experts agree that human activities have accelerated the rate of species extinction. The exact rate remains controversial – perhaps 100 to 1000 times the normal background rate of extinction. Anthropogenic extinctions started as humans migrated out of Africa over 60,000 years ago. Increases in global rates of extinction have been elevated above background rates since at least 1500, and appear to have accelerated in

8580-515: The Earth's time scale, except in a Solar System context. The existence, timing, and terrestrial effects of the Late Heavy Bombardment are still a matter of debate. The geologic history of Earth's Moon has been divided into a time scale based on geomorphological markers, namely impact cratering , volcanism , and erosion . This process of dividing the Moon's history in this manner means that

8712-447: The ICS has taken responsibility for producing and distributing the ICC citing the commercial nature, independent creation, and lack of oversight by the ICS on the prior published GTS versions (GTS books prior to 2013) although these versions were published in close association with the ICS. Subsequent Geologic Time Scale books (2016 and 2020 ) are commercial publications with no oversight from

8844-404: The ICS, and do not entirely conform to the chart produced by the ICS. The ICS produced GTS charts are versioned (year/month) beginning at v2013/01. At least one new version is published each year incorporating any changes ratified by the ICS since the prior version. The following five timelines show the geologic time scale to scale. The first shows the entire time from the formation of the Earth to

8976-415: The ICS. While some regional terms are still in use, the table of geologic time conforms to the nomenclature , ages, and colour codes set forth by the International Commission on Stratigraphy in the official International Chronostratigraphic Chart. The International Commission on Stratigraphy also provide an online interactive version of this chart. The interactive version is based on a service delivering

9108-578: The Industrial Revolution as the start of Anthropocene. Lovelock proposes that the Anthropocene began with the first application of the Newcomen atmospheric engine in 1712. The Intergovernmental Panel on Climate Change takes the pre-industrial era (chosen as the year 1750) as the baseline related to changes in long-lived, well mixed greenhouse gases. Although it is apparent that the Industrial Revolution ushered in an unprecedented global human impact on

9240-710: The Royal Society B , Rodolfo Dirzo , Gerardo Ceballos, and Paul R. Ehrlich write that the term is "increasingly penetrating the lexicon of not only the academic socio-sphere, but also society more generally", and is now included as an entry in the Oxford English Dictionary . The University of Cambridge, as another example, offers a degree in Anthropocene Studies. In the public sphere, the term Anthropocene has become increasingly ubiquitous in activist, pundit, and political discourses. Some who are critical of

9372-475: The addition of fertilisers, contamination, sealing, or enrichment with artefacts (in the World Reference Base for Soil Resources they are classified as Anthrosols and Technosols ). An example from archaeology would be dark earth phenomena when long-term human habitation enriches the soil with black carbon . Anthropogenic soils are recalcitrant repositories of artefacts and properties that testify to

9504-410: The atmospheric CO 2 , and infiltrating the biosphere , through ocean-atmosphere gas exchange . Increase in thyroid cancer rates around the world is also surmised to be correlated with increasing proportions of the I radionuclide. The highest global concentration of radionuclides was estimated to have been in 1965, one of the dates which has been proposed as a possible benchmark for the start of

9636-453: The atmospheric conditions across the Earth, or regional, focusing on specific areas with greater resolution. Global models typically have lower horizontal resolution and represent less complex chemical mechanisms but they simulate a larger area, while regional models can represent smaller areas with higher resolution and more detail. A major challenge in atmospheric modeling is balancing the number of chemical compounds and reactions included in

9768-439: The beginning of the Anthropocene. Other scholars pointed to the diachronous character of the physical strata of the Anthropocene, arguing that onset and impact are spread out over time, not reducible to a single instant or date of start. A January 2016 report on the climatic, biological, and geochemical signatures of human activity in sediments and ice cores suggested the era since the mid-20th century should be recognised as

9900-497: The behavior of the atmosphere. These numerical models solve the differential equations governing the concentrations of chemicals in the atmosphere. Depending on the complexity, these models can range from simple to highly detailed. Models can be zero-, one-, two-, or three-dimensional, each with various uses and advantages. Three-dimensional chemical transport models offer the most realistic simulations but require substantial computational resources. These models can be global, simulating

10032-518: The bodies of plants and animals", with the 13th-century Dominican bishop Albertus Magnus (c. 1200–1280) extending this into a theory of a petrifying fluid. These works appeared to have little influence on scholars in Medieval Europe who looked to the Bible to explain the origins of fossils and sea-level changes, often attributing these to the ' Deluge ', including Ristoro d'Arezzo in 1282. It

10164-420: The causes of these problems. By developing a theoretical understanding, they can test potential solutions and evaluate the effects of changes in government policy. Besides the major components listed above, the Earth's atmosphere contains many trace gas species that vary significantly depending on nearby sources and sinks. These trace gasses include compounds such as CFCs/HCFCs which are particularly damaging to

10296-412: The cave environment . Calthemites grow on or under man-made structures (including mines and tunnels) and mimic the shapes and forms of cave speleothems , such as stalactites , stalagmites , flowstone etc . Human activities like deforestation and road construction are believed to have elevated average total sediment fluxes across the Earth's surface. However, construction of dams on many rivers around

10428-401: The complex interactions from Earth’s systems that can be difficult to measure on a large scale. Experiments are performed in controlled environments, such as smog chambers, that allow for the individual evaluation of specific chemical reactions or the assessment of properties of a particular atmospheric constituent. A closely related subdiscipline is atmospheric photochemistry , which quantifies

10560-566: The cooling of the Earth or the Sun using basic thermodynamics or orbital physics. These estimations varied from 15,000 million years to 0.075 million years depending on method and author, but the estimations of Lord Kelvin and Clarence King were held in high regard at the time due to their pre-eminence in physics and geology. All of these early geochronometric determinations would later prove to be incorrect. The discovery of radioactive decay by Henri Becquerel , Marie Curie , and Pierre Curie laid

10692-762: The corresponding geochronologic unit sharing the same name with a change to the suffix (e.g. Phanerozoic Eonothem becomes the Phanerozoic Eon). Names of erathems in the Phanerozoic were chosen to reflect major changes in the history of life on Earth: Paleozoic (old life), Mesozoic (middle life), and Cenozoic (new life). Names of systems are diverse in origin, with some indicating chronologic position (e.g., Paleogene), while others are named for lithology (e.g., Cretaceous), geography (e.g., Permian ), or are tribal (e.g., Ordovician ) in origin. Most currently recognised series and subseries are named for their position within

10824-406: The developments in mass spectrometry pioneered by Francis William Aston , Arthur Jeffrey Dempster , and Alfred O. C. Nier during the early to mid- 20th century would finally allow for the accurate determination of radiometric ages, with Holmes publishing several revisions to his geological time-scale with his final version in 1960. The establishment of the IUGS in 1961 and acceptance of

10956-404: The different layers of stone unless they had been upon the shore and had been covered over by earth newly thrown up by the sea which then became petrified? And if the above-mentioned Deluge had carried them to these places from the sea, you would find the shells at the edge of one layer of rock only, not at the edge of many where may be counted the winters of the years during which the sea multiplied

11088-542: The dominance of the human impact, and hence appear to be reliable markers for the Anthropocene. Some anthropogenic soils may be viewed as the 'golden spikes' of geologists ( Global Boundary Stratotype Section and Point ), which are locations where there are strata successions with clear evidences of a worldwide event, including the appearance of distinctive fossils. Drilling for fossil fuels has also created holes and tubes which are expected to be detectable for millions of years. The astrobiologist David Grinspoon has proposed that

11220-561: The entire Black Sea may have changed during the last 2000 years as a result of nutrient and silica input from eroding deforested lands along the Danube River . Researchers have found that the growth of the human population and expansion of human activity has resulted in many species of animals that are normally active during the day, such as elephants, tigers and boars, becoming nocturnal to avoid contact with humans, who are largely diurnal. One geological symptom resulting from human activity

11352-420: The final proposal. Possible markers include microplastics , heavy metals , or radioactive nuclei left by tests from thermonuclear weapons . In November 2021, an alternative proposal that the Anthropocene is a geological event , not an epoch, was published and later expanded in 2022. This challenged the assumption underlying the case for the Anthropocene epoch - the idea that it is possible to accurately assign

11484-414: The formally defined Anthropocene. Human burning of fossil fuels has also left distinctly elevated concentrations of black carbon, inorganic ash, and spherical carbonaceous particles in recent sediments across the world. Concentrations of these components increases markedly and almost simultaneously around the world beginning around 1950. A marker that accounts for a substantial global impact of humans on

11616-609: The formation and growth of aerosols . Commonly used analytical instruments include ambient and particulate air samplers , scanning mobility particle sizers , gas chromatographs , and mass spectrometers . Models are essential tools for interpreting observational data, testing hypotheses about chemical reactions, and predicting future concentrations of atmospheric chemicals. To synthesize and test theoretical understanding of atmospheric chemistry, researchers commonly use computer models, such as chemical transport models . These models can be seen as mathematical representations that replicate

11748-527: The fossil record, as will species introductions. An example cited is the domestic chicken, originally the red junglefowl Gallus gallus , native to south-east Asia but has since become the world's most common bird through human breeding and consumption, with over 60 billion consumed annually and whose bones would become fossilised in landfill sites. Hence, landfills are important resources to find "technofossils". In terms of trace elements, there are distinct signatures left by modern societies. For example, in

11880-414: The foundational principles of determining the correlation of strata relative to geologic time. Over the course of the 18th-century geologists realised that: The apparent, earliest formal division of the geologic record with respect to time was introduced during the era of Biblical models by Thomas Burnet who applied a two-fold terminology to mountains by identifying " montes primarii " for rock formed at

12012-478: The geologic record." The official start-dates, according to the panel, would coincide with either the radionuclides released into the atmosphere from bomb detonations in 1945, or with the Limited Nuclear Test Ban Treaty of 1963. The peak in radionuclides fallout consequential to atomic bomb testing during the 1950s is another possible date for the beginning of the Anthropocene (the detonation of

12144-458: The geologic time scale of Earth. This table is arranged with the most recent geologic periods at the top, and the oldest at the bottom. The height of each table entry does not correspond to the duration of each subdivision of time. As such, this table is not to scale and does not accurately represent the relative time-spans of each geochronologic unit. While the Phanerozoic Eon looks longer than

12276-492: The ground work for radiometric dating, but the knowledge and tools required for accurate determination of radiometric ages would not be in place until the mid-1950s. Early attempts at determining ages of uranium minerals and rocks by Ernest Rutherford , Bertram Boltwood , Robert Strutt , and Arthur Holmes, would culminate in what are considered the first international geological time scales by Holmes in 1911 and 1913. The discovery of isotopes in 1913 by Frederick Soddy , and

12408-452: The human enterprise gives a mass-based quantitative and symbolic characterization of the human-induced epoch of the Anthropocene." Although the validity of Anthropocene as a scientific term remains disputed, its underlying premise, i.e., that humans have become a geological force, or rather, the dominant force shaping the Earth's climate, has found traction among academics and the public. In an opinion piece for Philosophical Transactions of

12540-503: The lake. In March 2024, the New York Times reported on the results of an internal vote held by the IUGS : After nearly 15 years of debate, the proposal to ratify the Anthropocene had been defeated by a 12-to-4 margin, with 2 abstentions. These results were not out of a dismissal of human impact on the planet, but rather an inability to constrain the Anthropocene in a geological context. This

12672-561: The layers of sand and mud brought down by the neighboring rivers and spread them over its shores. And if you wish to say that there must have been many deluges in order to produce these layers and the shells among them it would then become necessary for you to affirm that such a deluge took place every year. These views of da Vinci remained unpublished, and thus lacked influence at the time; however, questions of fossils and their significance were pursued and, while views against Genesis were not readily accepted and dissent from religious doctrine

12804-453: The lower boundaries of chronostratigraphic units. Defining chronostratigraphic units in such a manner allows for the use of global, standardised nomenclature. The International Chronostratigraphic Chart represents this ongoing effort. Several key principles are used to determine the relative relationships of rocks and thus their chronostratigraphic position. The law of superposition that states that in undeformed stratigraphic sequences

12936-455: The model with the accuracy of physical processes such as transport and mixing in the atmosphere. For example, box modeling is relatively simple and may include hundreds or even thousands of chemical reactions, but they typically use a very crude representation of atmospheric mixing. This makes them useful for studying specific chemical reactions, but limited in stimulating real-world dynamics. In contrast, 3D models are more complex, representing

13068-579: The model-building process by selecting relevant chemical reactions from databases based on a user-defined set of chemical constituents. Once the reactions are chosen, the code generator automatically constructs the ordinary differential equations that describe their time evolution, greatly reducing the time and effort required for model construction. One important current trend is using atmospheric chemistry as part of Earth system models . These models integrate atmospheric chemistry with other Earth system components, such as biosphere and hydrosphere , enabling

13200-455: The movement of many species into regions formerly too cold for them, often at rates faster than initially expected. Permanent changes in the distribution of organisms from human influence will become identifiable in the geologic record . This has occurred in part as a result of changing climate, but also in response to farming and fishing, and to the accidental introduction of non-native species to new areas through global travel. The ecosystem of

13332-450: The ocean due to dams, reservoirs and diversions. Humans have produced so many millions of tons of plastic each year since the early 1950s that microplastics are "forming a near-ubiquitous and unambiguous marker of Anthropocene". The study highlights a strong correlation between global human population size and growth, global productivity and global energy use and that the "extraordinary outburst of consumption and productivity demonstrates how

13464-489: The oldest strata will lie at the bottom of the sequence, while newer material stacks upon the surface. In practice, this means a younger rock will lie on top of an older rock unless there is evidence to suggest otherwise. The principle of original horizontality that states layers of sediments will originally be deposited horizontally under the action of gravity. However, it is now known that not all sedimentary layers are deposited purely horizontally, but this principle

13596-440: The ozone layer, and H2S which has a characteristic foul odor of rotten eggs and can be smelt in concentrations as low as 0.47 ppb. Some approximate amounts near the surface of some additional gasses are listed below. In addition to gasses, the atmosphere contains particles such as aerosol , which includes examples such as droplets, ice crystals, bacteria, and dust. The first scientific studies of atmospheric composition began in

13728-408: The pertinent time span. As of April 2022 these proposed changes have not been accepted by the ICS. The proposed changes (changes from the current scale [v2023/09]) are italicised: Proposed pre-Cambrian timeline (GTS2012), shown to scale: Current ICC pre-Cambrian timeline (v2023/09), shown to scale: The following table summarises the major events and characteristics of the divisions making up

13860-473: The planet, much of Earth's landscape already had been profoundly modified by human activities. The human impact on Earth has grown progressively, with few substantial slowdowns. A 2024 scientific perspective paper authored by a group of scientists led by William J. Ripple proposed the start of the Anthropocene around 1850, stating it is a "compelling choice . . . from a population, fossil fuel, greenhouse gasses, temperature, and land use perspective." In May 2019

13992-452: The present, but this gives little space for the most recent eon. The second timeline shows an expanded view of the most recent eon. In a similar way, the most recent era is expanded in the third timeline, the most recent period is expanded in the fourth timeline, and the most recent epoch is expanded in the fifth timeline. Horizontal scale is Millions of years (above timelines) / Thousands of years (below timeline) First suggested in 2000,

14124-485: The principles of superposition, original horizontality, lateral continuity, and cross-cutting relationships. From this Steno reasoned that strata were laid down in succession and inferred relative time (in Steno's belief, time from Creation ). While Steno's principles were simple and attracted much attention, applying them proved challenging. These basic principles, albeit with improved and more nuanced interpretations, still form

14256-597: The proposal to the International Geological Congress in August 2016. In May 2019, the AWG voted in favour of submitting a formal proposal to the ICS by 2021. The proposal located potential stratigraphic markers to the mid-20th century. This time period coincides with the start of the Great Acceleration , a post- World War II time period during which global population growth , pollution and exploitation of natural resources have all increased at

14388-424: The rate that molecules are split apart by sunlight, determines the resulting products, and obtains thermodynamic data such as Henry's law coefficients. Laboratory measurements are essential to understanding the sources and sinks of pollutants and naturally occurring compounds. Types of analysis that are of interest include both those on gas-phase reactions, as well as heterogeneous reactions that are relevant to

14520-467: The rest, it merely spans ~539 million years (~12% of Earth's history), whilst the previous three eons collectively span ~3,461 million years (~76% of Earth's history). This bias toward the most recent eon is in part due to the relative lack of information about events that occurred during the first three eons compared to the current eon (the Phanerozoic). The use of subseries/subepochs has been ratified by

14652-563: The rise of agriculture and the Neolithic Revolution (around 12,000 years BP ). Evidence of relative human impact – such as the growing human influence on land use, ecosystems, biodiversity , and species extinction – is substantial; scientists think that human impact has significantly changed (or halted) the growth of biodiversity. Those arguing for earlier dates posit that the proposed Anthropocene may have begun as early as 14,000–15,000 years BP , based on geologic evidence; this has led other scientists to suggest that "the onset of

14784-630: The rock record to bring it in line with the post-Tonian geologic time scale. This work assessed the geologic history of the currently defined eons and eras of the pre-Cambrian, and the proposals in the "Geological Time Scale" books 2004, 2012, and 2020. Their recommend revisions of the pre-Cryogenian geologic time scale were (changes from the current scale [v2023/09] are italicised): Proposed pre-Cambrian timeline (Shield et al. 2021, ICS working group on pre-Cryogenian chronostratigraphy), shown to scale: Current ICC pre-Cambrian timeline (v2023/09), shown to scale: The book, Geologic Time Scale 2012,

14916-474: The sea had at times transgressed over the land and at other times had regressed . This view was shared by a few of Xenophanes's contemporaries and those that followed, including Aristotle (384–322 BCE) who (with additional observations) reasoned that the positions of land and sea had changed over long periods of time. The concept of deep time was also recognised by Chinese naturalist Shen Kuo (1031–1095) and Islamic scientist -philosophers, notably

15048-496: The site of the Apollo ;11 Lunar landing, with the disturbances and artifacts that are so uniquely characteristic of our species' technological activity and which will survive over geological time spans could be considered as the 'golden spike' of the Anthropocene. An October 2020 study coordinated by University of Colorado at Boulder found that distinct physical, chemical and biological changes to Earth's rock layers began around

15180-455: The term Anthropocene nevertheless concede that "For all its problems, [it] carries power." The popularity and currency of the word has led scholars to label the term a "charismatic meta-category" or "charismatic mega-concept." The term, regardless, has been subject to a variety of criticisms from social scientists, philosophers, Indigenous scholars, and others. Epoch (geology) The geologic time scale or geological time scale ( GTS )

15312-418: The tests are Cs , Sr , Pu , Pu , Am , and I . These have been found to have had significant impact on the environment and on human beings. In particular, Cs and Sr have been found to have been released into the marine environment and led to bioaccumulation over a period through food chain cycles. The carbon isotope C , commonly released during nuclear tests, has also been found to be integrated into

15444-537: The time during which the rocks were laid down, and the collection of rocks themselves (i.e., it was correct to say Tertiary rocks, and Tertiary Period). Only the Quaternary division is retained in the modern geologic time scale, while the Tertiary division was in use until the early 21st century. The Neptunism and Plutonism theories would compete into the early 19th century with a key driver for resolution of this debate being

15576-730: The time of the 'Deluge', and younger " monticulos secundarios" formed later from the debris of the " primarii" . Anton Moro (1687–1784) also used primary and secondary divisions for rock units but his mechanism was volcanic. In this early version of the Plutonism theory, the interior of Earth was seen as hot, and this drove the creation of primary igneous and metamorphic rocks and secondary rocks formed contorted and fossiliferous sediments. These primary and secondary divisions were expanded on by Giovanni Targioni Tozzetti (1712–1783) and Giovanni Arduino (1713–1795) to include tertiary and quaternary divisions. These divisions were used to describe both

15708-562: The time scale boundaries do not imply fundamental changes in geological processes, unlike Earth's geologic time scale. Five geologic systems/periods ( Pre-Nectarian , Nectarian , Imbrian , Eratosthenian , Copernican ), with the Imbrian divided into two series/epochs (Early and Late) were defined in the latest Lunar geologic time scale. The Moon is unique in the Solar System in that it is the only other body from which humans have rock samples with

15840-585: The time they were laid down in is the geochronologic unit, e.g., the rocks that represent the Silurian System are the Silurian System and they were deposited during the Silurian Period. This definition means the numeric age of a geochronologic unit can be changed (and is more often subject to change) when refined by geochronometry while the equivalent chronostratigraphic unit (the revision of which

15972-407: The timing and relationships of events in geologic history. The time scale has been developed through the study of rock layers and the observation of their relationships and identifying features such as lithologies , paleomagnetic properties, and fossils . The definition of standardised international units of geologic time is the responsibility of the International Commission on Stratigraphy (ICS),

16104-405: The total environment, comparable in scale to those associated with significant perturbations of the geological past, is needed in place of minor changes in atmosphere composition. A useful candidate for holding markers in the geologic time record is the pedosphere . Soils retain information about their climatic and geochemical history with features lasting for centuries or millennia. Human activity

16236-564: The twenty-nine members of the Anthropocene Working Group (AWG) proposed a start date for the Epoch in the mid-20th century, as that period saw "a rapidly rising human population accelerated the pace of industrial production, the use of agricultural chemicals and other human activities. At the same time, the first atomic-bomb blasts littered the globe with radioactive debris that became embedded in sediments and glacial ice, becoming part of

16368-426: The type and relationships of unconformities in strata allows geologist to understand the relative timing the strata. The principle of faunal succession (where applicable) that states rock strata contain distinctive sets of fossils that succeed each other vertically in a specific and reliable order. This allows for a correlation of strata even when the horizon between them is not continuous. The geologic time scale

16500-548: The unit Ma (megaannum, for 'million years '). For example, 201.4 ± 0.2 Ma, the lower boundary of the Jurassic Period, is defined as 201,400,000 years old with an uncertainty of 200,000 years. Other SI prefix units commonly used by geologists are Ga (gigaannum, billion years), and ka (kiloannum, thousand years), with the latter often represented in calibrated units ( before present ). The names of geologic time units are defined for chronostratigraphic units with

16632-526: The work of James Hutton (1726–1797), in particular his Theory of the Earth , first presented before the Royal Society of Edinburgh in 1785. Hutton's theory would later become known as uniformitarianism , popularised by John Playfair (1748–1819) and later Charles Lyell (1797–1875) in his Principles of Geology . Their theories strongly contested the 6,000 year age of the Earth as suggested determined by James Ussher via Biblical chronology that

16764-488: The world means the rates of sediment deposition in any given place do not always appear to increase in the Anthropocene. For instance, many river deltas around the world are actually currently starved of sediment by such dams, and are subsiding and failing to keep up with sea level rise, rather than growing. Increases in erosion due to farming and other operations will be reflected by changes in sediment composition and increases in deposition rates elsewhere. In land areas with

16896-553: The year 1950. The research revealed that since about 1950, humans have doubled the amount of fixed nitrogen on the planet through industrial production for agriculture, created a hole in the ozone layer through the industrial scale release of chlorofluorocarbons (CFCs), released enough greenhouse gasses from fossil fuels to cause planetary level climate change , created tens of thousands of synthetic mineral-like compounds that do not naturally occur on Earth, and caused almost one-fifth of river sediment worldwide to no longer reach

17028-429: Was accepted at the time by western religion. Instead, using geological evidence, they contested Earth to be much older, cementing the concept of deep time. During the early 19th century William Smith , Georges Cuvier , Jean d'Omalius d'Halloy , and Alexandre Brongniart pioneered the systematic division of rocks by stratigraphy and fossil assemblages. These geologists began to use the local names given to rock units in

17160-415: Was in some places unwise, scholars such as Girolamo Fracastoro shared da Vinci's views, and found the attribution of fossils to the 'Deluge' absurd. Niels Stensen, more commonly known as Nicolas Steno (1638–1686), is credited with establishing four of the guiding principles of stratigraphy. In De solido intra solidum naturaliter contento dissertationis prodromus Steno states: Respectively, these are

17292-535: Was not until the Italian Renaissance when Leonardo da Vinci (1452–1519) would reinvigorate the relationships between stratification, relative sea-level change, and time, denouncing attribution of fossils to the 'Deluge': Of the stupidity and ignorance of those who imagine that these creatures were carried to such places distant from the sea by the Deluge...Why do we find so many fragments and whole shells between

17424-413: Was the last commercial publication of an international chronostratigraphic chart that was closely associated with the ICS. It included a proposal to substantially revise the pre-Cryogenian time scale to reflect important events such as the formation of the Solar System and the Great Oxidation Event , among others, while at the same time maintaining most of the previous chronostratigraphic nomenclature for

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