The Anthropocene: Comparing Its Meaning in Geology

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The Anthropocene: Comparing Its Meaning in Geology REVIEW ARTICLE The Anthropocene: Comparing Its Meaning in Geology 10.1029/2020EF001896 (Chronostratigraphy) with Conceptual Approaches Key Points: Arising in Other Disciplines • The Anthropocene concept developed in the Earth System Jan Zalasiewicz1 , Colin N. Waters1 , Erle C. Ellis2 , Martin J. Head3 , Davor Vidas4 , science community is closely Will Steffen5, Julia Adeney Thomas6, Eva Horn7, Colin P. Summerhayes8 , consistent with its proposed 9 10 11 1 chronostratigraphic (geological) Reinhold Leinfelder , J. R. McNeill , Agnieszka Gałuszka , Mark Williams , 12 13 8 14 definition Anthony D. Barnosky , Daniel de B. Richter , Philip L. Gibbard , Jaia Syvitski , • A wide range of other meanings Catherine Jeandel15 , Alejandro Cearreta16 , Andrew B. Cundy17 , Ian J. Fairchild18 , of the Anthropocene subsequently Neil L. Rose19 , Juliana A. Ivar do Sul20 , William Shotyk21, Simon Turner19 , emerged that represent inherently Michael Wagreich22 , and Jens Zinke1 valid, but partly different, concepts • Cross-disciplinary discussion is 1Geography, Geology and the Environment, University of Leicester, Leicester, UK, 2Geography & Environmental encouraged to help resolve issues of 3 meaning and communication in this Systems, University of Maryland, Baltimore, MD, USA, Earth Sciences, Brock University, St. Catharines, ON, 4 5 important area Canada, The Fridtjof Nansen Institute, Lysaker, Norway, Fenner School of Environment and Society, The Australian National University, Canberra, Australia, 6History, University of Notre Dame, South Bend, IN, USA, 7German Studies, University of Vienna, Vienna, Austria, 8Scott Polar Research Institute, University of Cambridge, Cambridge, UK, Correspondence to: 9Geological Sciences, Freie Universität, Berlin, Germany, 10Department of History, Georgetown University, Washington, J. Zalasiewicz, 11 12 [email protected] DC, USA, Institute of Chemistry, Jan Kochanowski University, Kielce, Poland, Jasper Ridge Biological Preserve and Department of Biology, Stanford University, Stanford, CA, USA, 13Nicholas School of the Environment, Duke University, Durham, NC, USA, 14Institute of Arctic and Alpine Research, University of Colorado, Boulder, CO, USA, Citation: 15LEGOS, Université de Toulouse, CNES, CNRS, IRD, Toulouse, France, 16Geología, Facultad de Ciencia y Tecnología, Zalasiewicz, J., Waters, C. N., Ellis, 17 E. C., Head, M. J., Vidas, D., Steffen, Universidad del País Vasco UPV/EHU, Bilbao, Spain, Ocean and Earth Science, University of Southampton, National 18 W., et al. (2021). The Anthropocene: Oceanography Centre (Southampton), Southampton, UK, School of Geography, Earth and Environmental Sciences, Comparing its meaning in geology University of Birmingham, Birmingham, UK, 19Geography, University College London, London, UK, 20Leibniz Institute (chronostratigraphy) with conceptual for Baltic Sea Research Warnemüende (IOW), Rostock, Germany, 21Renewable Resources, University of Alberta, approaches arising in other disciplines. 22 Edmonton, AB, Canada, Geology, University of Vienna, Vienna, Austria Earth's Future, 9, e2020EF001896. https://doi.org/10.1029/2020EF001896 The term Anthropocene initially emerged from the Earth System science community in Received 18 NOV 2020 Abstract Accepted 1 FEB 2021 the early 2000s, denoting a concept that the Holocene Epoch has terminated as a consequence of human activities. First associated with the onset of the Industrial Revolution, it was then more closely linked Author Contributions: with the Great Acceleration in industrialization and globalization from the 1950s that fundamentally Conceptualization: Jan Zalasiewicz, modified physical, chemical, and biological signals in geological archives. Since 2009, the Anthropocene Colin N. Waters, Erle C. Ellis, Martin J. has been evaluated by the Anthropocene Working Group, tasked with examining it for potential Head, Davor Vidas, Will Steffen, Julia inclusion in the Geological Time Scale. Such inclusion requires a precisely defined chronostratigraphic Adeney Thomas, Eva Horn, Colin P. Summerhayes, Reinhold Leinfelder, J. and geochronological unit with a globally synchronous base and inception, with the mid-twentieth R. McNeill, Agnieszka Gałuszka, Mark century being geologically optimal. This reflects an Earth System state in which human activities have Williams, Anthony D. Barnosky, Daniel become predominant drivers of modifications to the stratigraphic record, making it clearly distinct de B. Richter, Philip L. Gibbard, Jaia Syvitski, Catherine Jeandel, Alejandro from the Holocene. However, more recently, the term Anthropocene has also become used for different Cearreta, Andrew B. Cundy, Ian J. conceptual interpretations in diverse scholarly fields, including the environmental and social sciences and Fairchild, Neil L. Rose, Juliana A. Ivar humanities. These are often flexibly interpreted, commonly without reference to the geological record, and do Sul, William Shotyk, Simon Turner, Michael Wagreich, Jens Zinke diachronous in time; they often extend much further back in time than the mid-twentieth century. These broader conceptualizations encompass wide ranges and levels of human impacts and interactions with the environment. Here, we clarify what the Anthropocene is in geological terms and compare the proposed geological (chronostratigraphic) definition with some of these broader interpretations and applications of the term “Anthropocene,” showing both their overlaps and differences. The Anthropocene concept, that modern human impacts on © 2021. The Authors. Plain Language Summary This is an open access article under Earth have been sufficient to bring in a new geological epoch, is only two decades old. In that short time, the terms of the Creative Commons its use has grown explosively, not only in the Earth sciences but also far more widely to spread through Attribution License, which permits use, the sciences generally, to spill over into the social sciences, arts, and humanities. This has led to welcome distribution and reproduction in any medium, provided the original work is discussions between diverse scholarly communities, though also to some very different interpretations properly cited. of the Anthropocene, when interpreted through different disciplinary lenses. Notably, the geological ZALASIEWICZ ET AL. 1 of 25 Earth’s Future 10.1029/2020EF001896 Writing – original draft: Jan interpretation used as basis for a potential unit of the Geological Time Scale, of a time unit starting Zalasiewicz, Colin N. Waters, Erle C. planet-wide and synchronously in the mid-twentieth century with the massive changes triggered by Ellis, Martin J. Head, Davor Vidas, Will Steffen, Julia Adeney Thomas, Eva industrialization and globalization, jars with interpretations of an Anthropocene that ranges back many Horn, Colin P. Summerhayes, Reinhold millennia to encompass early human environmental impacts. We analyze and compare these diverse Leinfelder, J. R. McNeill, Agnieszka standpoints and their effect upon evolving disciplinary practices, and discuss approaches that could make Gałuszka, Mark Williams, Anthony D. Barnosky, Daniel de B. Richter, Philip communication clearer and enhance cross-disciplinary exchanges. L. Gibbard, Jaia Syvitski, Catherine Jeandel, Alejandro Cearreta, Andrew B. Cundy, Ian J. Fairchild, Neil L. Rose, Juliana A. Ivar do Sul, William Shotyk, 1. Introduction Simon Turner, Michael Wagreich, Jens The term Anthropocene was coined by Paul Crutzen in 2000 (Crutzen, 2002; Crutzen & Stoermer, 2000) Zinke Writing – review & editing: Jan during a review of the first decade of research in the International Geosphere–Biosphere Programme Zalasiewicz, Colin N. Waters, Erle C. (IGBP). The term crystallized the growing realization in the Earth System science (ESS) community that Ellis, Martin J. Head, Davor Vidas, Will human activities were fundamentally changing the Earth System (Steffen et al., 2020). The ESS focus on Steffen, Julia Adeney Thomas, Eva Horn, Colin P. Summerhayes, Reinhold planetary processes, including significant global changes to the atmosphere, biosphere, cryosphere, geo- Leinfelder, J. R. McNeill, Agnieszka sphere, hydrosphere, pedosphere, technosphere, and the climate, demonstrated that conditions typical of Gałuszka, Mark Williams, Anthony D. the Holocene (specifically, the last 11,700 years of Earth history) no longer resembled those of the present Barnosky, Daniel de B. Richter, Philip L. Gibbard, Jaia Syvitski, Catherine day. In proposing this new term, Crutzen and Stoermer (2000, p. 17) indicated the onset of the Anthropo- Jeandel, Alejandro Cearreta, Andrew cene as “the latter part of the 18th century … when data retrieved from glacial ice cores show the beginning B. Cundy, Ian J. Fairchild, Neil L. Rose, of a growth in the atmospheric concentrations of several ‘greenhouse gases’, in particular CO2 and CH4.” Juliana A. Ivar do Sul, William Shotyk, Simon Turner, Michael Wagreich, Jens They, and Crutzen (2002), linked this physical record with the global effects of human activities associated Zinke with the onset of the Industrial Revolution in the UK, catalyzed by the development of a greatly improved steam engine by James Watt. Continued research within the IGBP community led to the recognition that there were sharp upward in- flections of many socioeconomic and resultant Earth System trends of global significance in the mid-twen- tieth century. The term for this, the “Great Acceleration,” was coined in a Dahlem Conference in 2005 that included social scientists and humanities scholars
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