This article reads like a press release or a news article and may be largely based on routine coverage .(January 2023) |
The Anthropocene Working Group (AWG) is an interdisciplinary research group dedicated to the study of the Anthropocene as a geological time unit. It was established in 2009 as part of the Subcommission on Quaternary Stratigraphy (SQS), a constituent body of the International Commission on Stratigraphy (ICS). As of 2021, the research group features 37 members, with the physical geographer Simon Turner as Secretary and the geologist Colin Neil Waters as chair of the group. The late Nobel Prize-winning Paul Crutzen, who popularized the word 'Anthropocene' in 2000, had also been a member of the group until he died on January 28, 2021. The main goal of the AWG is providing scientific evidence robust enough for the Anthropocene to be formally ratified by the International Union of Geological Sciences (IUGS) as an epoch within the Geologic time scale. [1]
Prior to the establishment of the Anthropocene Working Group in 2009, no research program dedicated to the formalization of the Anthropocene in the geologic time scale existed. The idea of naming the current epoch 'Anthropocene' rather than using its formal time unit, the Holocene, became popular after Paul Crutzen and Eugene Stoermer published in May 2000 an article on the IGBP Global Change Newsletter called "The 'Anthropocene'." [2] Later in 2002, Crutzen published a commentary on Nature titled "Geology of Mankind" where he further stressed the idea "to assign the term ‘Anthropocene’ to the present, in many ways human-dominated, geological epoch, supplementing the Holocene," [3] with starting date in the late 18th century (at the onset of the Industrial Revolution). Soon after Paul Crutzen published his influential articles, a debate over the beginning of the Anthropocene took place between supporters of the Early Anthropocene Hypothesis, a thesis originally promoted in 2003 by the palaeoclimatologist William Ruddiman dating the beginning of the Anthropocene as far back as the Neolithic Revolution, [4] and supporters of more recent starting dates, from European Colonization of the Americas, [5] [6] [7] to the late 18th century, to the post-WWII Great Acceleration. [8] [9]
The discussion over the beginning of the Anthropocene was crucial for the 'stratigraphic turn' [10] that the Anthropocene debate took in the following years. In February 2008, Jan Zalasiewicz and other members of the Stratigraphy Commission of the Geological Society of London published a paper that considered the possibility to "amplify and extend the discussion of the effects referred to by Crutzen and then apply the same criteria used to set up new epochs to ask whether there really is justification or need for a new term, and if so, where and how its boundary might be placed." [11] The article raised the possibility of studying the Anthropocene as a discrete geological unit—a possibility that later led to the establishment of the AWG.
In 2009, the Subcommission on Quaternary Stratigraphy established an Anthropocene Working Group to "examine the status, hierarchical level and definition of the Anthropocene as a potential new formal division of the Geological Time Scale." [12] Some authors have labelled this moment as 'stratigraphic turn' [13] or 'geological turn', [14] in that the establishment of the AWG acknowledged the Anthropocene as an object of geological interest in the scientific community. The AWG has been actively publishing ever since then. The first in-person meeting of the AWG took place in October 2014 at Haus der Kulturen der Welt, Berlin (HKW), with several other work meetings at HKW to follow in subsequent years. The AWG became a close collaborator of the HKW's and Max Planck Institute for the History of Science's decade long Anthropocene Project. [15] Within the framework of that project, HKW was able to acquired in 2018 financial support for a systematic assessment of potential candidates for the Anthropocene's Global boundary Stratotype Section and Point (GSSP) by the AWG through means of a special appropriation from the German Bundestag. [16]
In 2020, Colin Waters, previously secretary of the AWG, became the new chair, replacing the paleobiologist Jan Zalasiewicz who had previously been chair of the AWG from 2009 to 2020, while Simon Turner became the new secretary of the group.
The Anthropocene Working Group is one of four workings groups part of the Subcommission on Quaternary Stratigraphy (the other three being the Pleistocene–Holocene boundary working group, Middle/Late Pleistocene boundary working group, and Early/Middle Pleistocene boundary working group). [17] The AWG members (including Paul Crutzen, who was awarded the Nobel prize for chemistry in 1995 for his researcher on ozone depletion; John McNeill, a pioneering researcher in the field of environmental history; and Naomi Oreskes, author of the book Merchants of Doubt ) have diverse disciplinary backgrounds, ranging from international law, archaeology, and history to philosophy, natural science, and geography. Since no direct funding supports the research program, communication among members happens mostly through email, whereas meetings are usually founded by hosting institutions.
As for most of the epochs in the Phanerozoic (the current Eon, starting 539 million years ago), determining the beginning of the Anthropocene by locating and agreeing upon its lower boundary is a necessary step in its process of formal recognition as a geochronological/chronostratigraphic unit. [18] A lower boundary is defined by locating a GSSP (informally known as 'golden spike') in the stratigraphic section of a stage, the chronostratigraphic taxonomic equivalent of an epoch. Alternatively, if a 'golden spike' cannot be located, a GSSA can be agreed upon, although this methodology is usually implemented for Precambrian boundaries. [19] There is a specific set of rules that a GSSP must fulfill in order to be recognized as a valid primary geologic marker. [20]
A central object of research for the AWG is establishing when, where, and how to locate the lower boundary of the Anthropocene. This means assigning a starting date to the Anthropocene (and an end to the Holocene), locating primary as well as auxiliary markers defining Anthropocene geologic record, and determining the proper methodology to implement in the overall process of formalization (GSSP or GSSA, what proxies to use as markers, etc.). Although debates on the taxonomical level of the Anthropocene in the chronostratigraphic chart / geologic time scale (Stage/Age, Series/Epoch, or System/Period) have occurred, the AWG has been considering the Anthropocene to best fit the requirements to be taxonomically recognized as an epoch. [21]
In January 2014, the Geological Society of London published A Stratigraphical Basis for the Anthropocene, [22] a collection of scientific essays dedicated to assessing and analyzing the anthropogenic signatures defining the Anthropocene, and its requirements to be recognized as a distinct chronostratigraphic unit from the Holocene. The volume constitutes a landmark publication for the AWG, collecting a preliminary body of scientific evidence for the Anthropocene, and establishing research areas and trajectories retraced in the following years.
In February 2019, the AWG published The Anthropocene as a Geological Time Unit: A Guide to the Scientific Evidence and Current Debate. It represents an extensive summary of evidence collected supporting the case of formalization of the Anthropocene as a geological time unit. The synthesis comprehends evidence ranging from stratigraphy, lithostratigraphy, mineralogy, biostratigraphy, chemostratigraphy, to climatology, Earth system science, and archaeology. The monograph also links the Anthropocene to the question concerning anthropogenic climate change, and the role of human technology and the technosphere in impacting the functioning of the Earth system. In the first chapter, the authors also provide a genealogy of the term 'Anthropocene,' and a statement of the role of the AWG as a scientific research program. [1]
In May, 2019, the AWG completed a binding vote determining two major research questions:
Both questions received a positive response, with 29 votes in favor, 4 votes against, and no abstention (33 votes received out of 34 potential voting members). [23]
On July 11, 2023, the AWG proposed Crawford Lake, Canada as GSSP candidate site of the Anthropocene series in a joint press conference with the Max Planck Society. [24] [25]
In 2016 seven prominent members of the AWG – Erle Ellis, John McNeill, Eric Odada, Andrew Revkin, Will Steffen, Davor Vidas and Jan Zalasiewicz – were interviewed in the feature documentary Anthropocene which showed on campuses and at film festivals worldwide and helped the term gain public attention. The documentary was the first feature-length film about the new epoch, and was described by Earth.com as one of the top ten documentaries to help raise environmental awareness. While the seven AWG members formed a broad consensus about the Anthropocene's history and the term's significance, they took contrasting views when invited by director Steve Bradshaw to consider the Anthropocene either as a tragedy – with extinctions and upheavals – or as a dark comedy.
A Global Boundary Stratotype Section and Point (GSSP), sometimes referred to as a golden spike, is an internationally agreed upon reference point on a stratigraphic section which defines the lower boundary of a stage on the geologic time scale. The effort to define GSSPs is conducted by the International Commission on Stratigraphy, a part of the International Union of Geological Sciences. Most, but not all, GSSPs are based on paleontological changes. Hence GSSPs are usually described in terms of transitions between different faunal stages, though far more faunal stages have been described than GSSPs. The GSSP definition effort commenced in 1977. As of 2024, 79 of the 101 stages that need a GSSP have a ratified GSSP.
The geologic time scale or geological time scale (GTS) is a representation of time based on the rock record of Earth. It is a system of chronological dating that uses chronostratigraphy and geochronology. It is used primarily by Earth scientists to describe 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), 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 Quaternary is the current and most recent of the three periods of the Cenozoic Era in the geologic time scale of the International Commission on Stratigraphy (ICS). It follows the Neogene Period and spans from 2.58 million years ago to the present. The Quaternary Period is divided into two epochs: the Pleistocene and the Holocene ; a proposed third epoch, the Anthropocene, was rejected in 2024 by IUGS, the governing body of the ICS.
The Anthropocene was a rejected proposal for a geological epoch following the Holocene, dating from the commencement of significant human impact on Earth up to the present day. This impact affects 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 the Anthropocene have been proposed, ranging from the beginning of the Neolithic Revolution, 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 the International Union of Geological Sciences (IUGS) rejected the Anthropocene Epoch proposal for inclusion in the Geologic Time Scale sparking significant disagreement from scientists working in the field.
The International Commission on Stratigraphy (ICS), sometimes unofficially referred to as the "International Stratigraphic Commission", is a daughter or major subcommittee grade scientific daughter organization that concerns itself with stratigraphical, geological, and geochronological matters on a global scale.
The Aalenian is a subdivision of the Middle Jurassic Epoch/Series of the geologic timescale that extends from about 174.7 ±0.8 Ma to about 170.9 ±0.8 Ma. It was preceded by the Toarcian and succeeded by the Bajocian.
The Gelasian is an age in the international geologic timescale or a stage in chronostratigraphy, being the earliest or lowest subdivision of the Quaternary Period/System and Pleistocene Epoch/Series. It spans the time between 2.58 Ma and 1.80 Ma. It follows the Piacenzian Stage and is followed by the Calabrian Stage.
In the geologic timescale, the Artinskian is an age or stage of the Permian. It is a subdivision of the Cisuralian Epoch or Series. The Artinskian likely lasted between 290.1 and 283.5 million years ago (Ma) according to the most recent revision of the International Commission on Stratigraphy (ICS) in 2022. It was preceded by the Sakmarian and followed by the Kungurian.
The Bartonian is, in the International Commission on Stratigraphy's (ICS) geologic time scale, a stage or age in the middle of the Eocene Epoch or Series. The Bartonian Age spans the time between 41.2 and37.71 Ma. It is preceded by the Lutetian and is followed by the Priabonian Age.
Calabrian is a subdivision of the Pleistocene Epoch of the geologic time scale, defined as 1.8 Ma—774,000 years ago ± 5,000 years, a period of ~1.026 million years.
The Priabonian is, in the ICS's geologic timescale, the latest age or the upper stage of the Eocene Epoch or Series. It spans the time between 37.71 and33.9 Ma. The Priabonian is preceded by the Bartonian and is followed by the Rupelian, the lowest stage of the Oligocene.
The Rupelian is, in the geologic timescale, the older of two ages or the lower of two stages of the Oligocene Epoch/Series. It spans the time between 33.9 and27.82 Ma. It is preceded by the Priabonian Stage and is followed by the Chattian Stage.
The Santonian is an age in the geologic timescale or a chronostratigraphic stage. It is a subdivision of the Late Cretaceous Epoch or Upper Cretaceous Series. It spans the time between 86.3 ± 0.7 mya and 83.6 ± 0.7 mya. The Santonian is preceded by the Coniacian and is followed by the Campanian.
In the geologic timescale, the Kimmeridgian is an age in the Late Jurassic Epoch and a stage in the Upper Jurassic Series. It spans the time between 154.8 ±0.8 Ma and 149.2 ±0.7 Ma. The Kimmeridgian follows the Oxfordian and precedes the Tithonian.
The Early Anthropocene Hypothesis is a stance concerning the beginning of the Anthropocene first proposed by William Ruddiman in 2003. It posits that the Anthropocene, a proposed geological epoch coinciding with the most recent period in Earth's history when the activities of the human race first began to have a significant global impact on Earth's climate and ecosystems, dates back to 8,000 years ago, triggered by intense farming activities after agriculture became widespread. It was at that time that atmospheric greenhouse gas concentrations stopped following the periodic pattern of rises and falls that had accurately characterized their past long-term behavior, a pattern that is explained by natural variations in Earth's orbit known as Milankovitch cycles. Ruddiman's proposed start-date has been met with criticism from scholars in a variety of fields.
A chronozone or chron is a unit in chronostratigraphy, defined by events such as geomagnetic reversals (magnetozones), or based on the presence of specific fossils . According to the International Commission on Stratigraphy, the term "chronozone" refers to the rocks formed during a particular time period, while "chron" refers to that time period.
The Meghalayan age is the name given in 2018, by the International Commission on Stratigraphy, to the current age or latest geologic age – or uppermost stage of the Quaternary. It is also the upper, or latest, of three subdivisions of the Holocene epoch or series. This way of breaking down time is based only on geology; for example, it is unrelated to the three-age system of historical periods into which human development is sometimes divided.
In the geologic time scale, the Greenlandian is the earliest age or lowest stage of the Holocene Epoch or Series, part of the Quaternary. Beginning in 11,650 BP and ending with the 8.2-kiloyear event, it is the earliest of three sub-divisions of the Holocene. It was officially ratified by the International Commission on Stratigraphy in June 2018 with the later Northgrippian and Meghalayan Ages/Stages. The lower boundary of the Greenlandian Age is the GSSP sample from the North Greenland Ice Core Project in central Greenland. The Greenlandian GSSP has been correlated with the end of Younger Dryas and a "shift in deuterium excess values".
In the geologic time scale, the Northgrippian is the middle one of three ages or stages of the Holocene Epoch or Series. It was officially ratified by the International Commission on Stratigraphy in June 2018 along with the earlier Greenlandian and later Meghalayan ages/stages. The age takes its name from the North Greenland Ice Core Project (NorthGRIP). The age began 8,276 BP, near the 8.2-kiloyear event, and goes up to the start of the Meghalayan, which began 4,200 BP, near the 4.2-kiloyear event.
A geological event is a temporary and spatially heterogeneous and dynamic (diachronous) happening in Earth history that contributes to the transformation of Earth system and the formation of geological strata. Event stratigraphy was first proposed as a system for the recognition, study and correlation of the effects of important physical or biological events on the broader stratigraphical record.