Papers on the Anthropocene

This is a list of papers on the new geological epoch called the Anthropocene. The list is not complete, and will most likely be updated in the future in order to make it more thorough and more representative.

The Anthropocene: is there a geomorphological case? – Brown et al. (2013) “The ‘Anthropocene’, as used to describe the interval of recent Earth history during which humans have had an ‘overwhelming’ effect on the Earth system, is now being formally considered as a possible new geological Epoch. Such a new geological time interval (possibly equivalent to the Pleistocene Epoch) requires both theoretical justification as well as empirical evidence preserved within the geological record. Since the geological record is driven by geomorphological processes, geomorphology has to be an integral part of this consideration given that it is Earth surface processes that produce terrestrial and near-shore stratigraphy. For this reason, the British Society for Geomorphology (BSG) has inaugurated a Fixed Term Working Group to consider this issue and advise the Society on how geomorphologists can engage with debates over the Anthropocene. This Commentary sets out the initial case for the formalisation of the Anthropocene and a priori considerations in the hope that it will stimulate debate amongst, and involvement by, the geomorphological community in what is a crucial issue for the discipline. The working Group is now considering the practical and aspects of such a formalisation including the relative magnitude problem, the boundary problem and the spatial diachrony of ‘anthropogenic geomorphology’.” Antony G. Brown, Stephen Tooth, Richard C. Chiverrell, Jim Rose, David S. G. Thomas, John Wainwright, Joanna E. Bullard, Varyl Thorndycraft, Rolf Aalto, Peter Downs, Earth Surface Processes and Landforms, DOI: 10.1002/esp.3368.

Agro-industrial alluvium in the Swale catchment, northern England, as an event marker for the Anthropocene – Foulds et al. (2013) “Physically and chemically distinctive late-Prehistoric and historical age alluvial deposits are characteristic of many upland and lowland river systems in the UK. Despite their widespread distribution, there have been few attempts to construct robust chronologies or to identify environmental factors that governed their formation. The Swale catchment in northern England is typical in this respect, with large areas of its valley floor covered by sedimentologically distinctive laminated sands and silts, enriched in organic material and Pb, and underlain by uncontaminated and structureless silts. Using ¹⁴C dating, chemostratigraphy, lichenometry and historical maps, a catchment-wide change in sedimentation style has been dated to between the mid 18th and early 19th centuries AD. Several causative factors were responsible for this change in sedimentation style and include the initiation of large-scale, intensive lead mining from the latter half of the 18th century onwards, embankment construction in the lowlands and historical peat erosion in the uplands. Transformation of the Swale floodplain also reflects longer-term land-use and climate change. In particular, deforestation of headwater tributaries by monastic grazing practices in the High Middle Ages (AD 1000–1300) led to a period of fine-grained sedimentation in upland catchments, as well as priming hillslopes for erosion and widespread channel network incision and increased fine sediment flux during the climatic downturn of the ‘Little Ice Age’. Sediment facies of a similar nature have been widely recorded in other northern English river catchments and represent a regional land use–climate signal characteristic of the Anthropocene. We introduce the term ‘agro-industrial alluvium’ to describe these types of deposit. They have similarities to post-settlement alluvium in North America and Australia, where historical land-use change had a similar impact on valley floor sedimentology.” Simon A Foulds, Mark G Macklin, Paul A Brewer, The Holocene January 8, 2013 0959683612465445, doi: 10.1177/0959683612465445.

Holocene and Anthropocene Landscape Change: Arroyo Formation on Santa Cruz Island, California – Perroy et al. (2012) “In this study, we untangle the relative importance of climatic, tectonic, and anthropogenic drivers as triggers of arroyo formation and geomorphic change for a small watershed on Santa Cruz Island, California. Within the Pozo watershed (6.47 km²), historic arroyo incision occurred contemporaneously with arroyo incision across many of the world’s dryland regions. Unlike many of these other sites, Pozo contains a datable record that allows quantification of sedimentation rates from the mid-to-late Holocene to the twentieth century. Basin-wide environmental changes were assessed using a combination of cosmogenic radionuclide inventories, midden and marine-shell deposits, relict soil properties, airborne and ground-based light detection and ranging (lidar) data, ranching artifacts, and historic records. Shortly after the introduction of sheep in 1853, localized sedimentation rates on the Pozo floodplain increased by two orders of magnitude from 0.4 mm/year to 25 mm/year. Accelerated sedimentation was followed by arroyo formation ca. 1878 and rapid expansion of the incipient gully network, the lateral extent of which has been largely maintained since 1929. Catchment-mean erosion rates from cosmogenic radionuclide measurements indicate that presettlement rates were less than 0.08 mm/year, whereas lidar-derived measurements of historic gully erosion produce estimates almost thirty times higher (2.2 mm/year). Topographic measurements since 2005 indicate that the active channel of the Pozo watershed is aggrading. We argue that accelerated sedimentation due to overgrazing, and an unusually large 1878 rainstorm event, set the stage for arroyo formation in the Pozo watershed between 1875 and 1886. We hypothesize that even in the absence of modern human disturbance, downcutting would have occurred due to intrinsic hillslope stability thresholds.” Ryan L. Perroy, Bodo Bookhagen, Oliver A. Chadwick & Jeffrey T. Howarth, Annals of the Association of American Geographers, Volume 102, Issue 6, 2012, DOI:10.1080/00045608.2012.715054.

Cause of the chalcophile trace element enrichments marking the Holocene to Anthropocene transition in northern Chesapeake Bay sediments – Dolor et al. (2012) “In Chesapeake Bay sediments, concentrations of 15 chalcophile trace elements, half rarely determined in estuaries, display historical profiles having remarkably similar features. All element concentrations rose more or less simultaneously in the 1920–1940 interval, creating a chemostratigraphic marker of the Holocene to Anthropocene transition. Subsequently, concentration maxima occurred at ∼20-year intervals, suggesting a link to a documented climate cycle of similar period. These elements’ correlated profiles suggest that sediments approximate binary mixtures of one lithogenic and one multi-element anthropogenic component. The latter component is characterized by these mass ratios (±standard error): [View Within Article]. Where comparisons are possible, these ratios differ from those of contaminants in the harbor of the region’s principal industrial city, Baltimore, but are surprisingly similar to those in sediment contaminants from the Susquehanna River, the Bay’s chief tributary. Thus both the anthropogenic and the lithogenic components in the Bay’s central channel appear to originate in the river basin. Many chalcophile element ratios in the anthropogenic component are similar to those in regional aerosols. If cumulative aerosol deposition on soils in the river basin is the source of the anthropogenic component, then the above ratios could be a regional anthropogenic signature that should be looked for more widely. Unlike Mo, the enrichment of these chalcophile elements in the Bay’s sediments is not controlled by seasonal anoxia; Mo apparently possesses a unique capacity to record past redox information about estuaries owing to its high seawater concentration.” Marvourneen K. Dolor, George R. Helz, William F. McDonough, Geochimica et Cosmochimica Acta, Volume 82, 1 April 2012, Pages 79–91, http://dx.doi.org/10.1016/j.gca.2010.06.040.

Is the Anthropocene an issue of stratigraphy or pop culture? – Autin & Holbrook (2012) “The term Anthropocene recently entered into the rhetoric of both the scientific community and the popular environmental movement. Scientific proponents argue that global industrialization drives accelerated Earth-system changes unrivaled in Earth’s history. The discussion now filters into geological stratigraphy with proposals to amend formal time stratigraphic nomenclature (Zalasiewicz et al., 2008, 2010). Environmentalists suggest that terms like Anthropocene foster broad social and cultural awareness of human-induced environmental changes. Advocates argue that greater awareness of humanity’s role in environmental change encourages sustainable resource utilization. Formal recognition of a new geologic epoch helps the broader scientific community solidify the idea of humanity as an Earth-system driver. Before the scientific community ventures too far, we wish to offer comment that considers the practicality of the Anthropocene to geological stratigraphy, the science to which it ultimately applies.” Whitney J. Autin, John M. Holbrook, GSA Today, Volume 22 Issue 7 (July 2012). [Full text]

The Anthropocene: a new epoch of geological time? – Zalasiewicz et al. (2011) “Anthropogenic changes to the Earth’s climate, land, oceans and biosphere are now so great and so rapid that the concept of a new geological epoch defined by the action of humans, the Anthropocene, is widely and seriously debated. Questions of the scale, magnitude and significance of this environmental change, particularly in the context of the Earth’s geological history, provide the basis for this Theme Issue. The Anthropocene, on current evidence, seems to show global change consistent with the suggestion that an epoch-scale boundary has been crossed within the last two centuries.” Jan Zalasiewicz, Mark Williams, Alan Haywood and Michael Ellis, Phil. Trans. R. Soc. A 13 March 2011 vol. 369 no. 1938 835-841, doi: 10.1098/rsta.2010.0339. [Full text]

The New World of the Anthropocene – Zalasiewicz et al. (2010) “The Anthropocene, following the lost world of the Holocene, holds challenges for both science and society.” Jan Zalasiewicz, Mark Williams, Will Steffen, Paul Crutzen, Environ. Sci. Technol., 2010, 44 (7), pp 2228–2231, DOI: 10.1021/es903118j. [Full text]

Are we now living in the Anthropocene? – Zalasiewicz et al. (2008) “The term Anthropocene, proposed and increasingly employed to denote the current interval of anthropogenic global environmental change, may be discussed on stratigraphic grounds. A case can be made for its consideration as a formal epoch in that, since the start of the Industrial Revolution, Earth has endured changes sufficient to leave a global stratigraphic signature distinct from that of the Holocene or of previous Pleistocene interglacial phases, encompassing novel biotic, sedimentary, and geochemical change. These changes, although likely only in their initial phases, are sufficiently distinct and robustly established for suggestions of a Holocene–Anthropocene boundary in the recent historical past to be geologically reasonable. The boundary may be defined either via Global Stratigraphic Section and Point (“golden spike”) locations or by adopting a numerical date. Formal adoption of this term in the near future will largely depend on its utility, particularly to earth scientists working on late Holocene successions. This datum, from the perspective of the far future, will most probably approximate a distinctive stratigraphic boundary.” Jan Zalasiewicz, Mark Williams, Alan Smith, Tiffany L. Barry, Angela L. Coe, Paul R. Bown, Patrick Brenchley, David Cantrill, Andrew Gale, Philip Gibbard, F. John Gregory, Mark W. Hounslow, Andrew C. Kerr, Paul Pearson, Robert Knox, John Powell, Colin Waters, John Marshall, Michael Oates, Peter Rawson, and Philip Stone, GSA Today 18 (2): 4-8, 1 Feb 2008. [Full text]

The Anthropocene: Are Humans Now Overwhelming the Great Forces of Nature – Steffen et al. (2007) “We explore the development of the Anthropocene, the current epoch in which humans and our societies have become a global geophysical force. The Anthropocene began around 1800 with the onset of industrialization, the central feature of which was the enormous expansion in the use of fossil fuels. We use atmospheric carbon dioxide concentration as a single, simple indicator to track the progression of the Anthropocene. From a preindustrial value of 270–275 ppm, atmospheric carbon dioxide had risen to about 310 ppm by 1950. Since then the human enterprise has experienced a remarkable explosion, the Great Acceleration, with significant consequences for Earth System functioning. Atmospheric CO₂ concentration has risen from 310 to 380 ppm since 1950, with about half of the total rise since the preindustrial era occurring in just the last 30 years. The Great Acceleration is reaching criticality. Whatever unfolds, the next few decades will surely be a tipping point in the evolution of the Anthropocene.” Will Steffen, Paul J. Crutzen, John R. McNeill, AMBIO: A Journal of the Human Environment 36(8):614-621. 2007, doi: http://dx.doi.org/10.1579/0044-7447(2007)36%5B614:TAAHNO%5D2.0.CO;2.

Humans as geologic agents: A deep-time perspective – Wilkinson (2005) “Humans move increasingly large amounts of rock and sediment during various construction activities, and mean rates of cropland soil loss may exceed rates of formation by up to an order of magnitude, but appreciating the actual importance of humans as agents of global erosion necessitates knowledge of prehistoric denudation rates imposed on land surfaces solely by natural processes. Amounts of weathering debris that compose continental and oceanic sedimentary rocks provide one such source of information and indicate that mean denudation over the past half-billion years of Earth history has lowered continental surfaces by a few tens of meters per million years. In comparison, construction and agricultural activities currently result in the transport of enough sediment and rock to lower all ice-free continental surfaces by a few hundred meters per million years. Humans are now an order of magnitude more important at moving sediment than the sum of all other natural processes operating on the surface of the planet. Relationships between temporal trends in land use and global population indicate that humans became the prime agents of erosion sometime during the latter part of the first millennium A.D.” Bruce H. Wilkinson, Geology, v. 33 no. 3 p. 161-164, doi: 10.1130/G21108.1. [Full text]

Fluvial filtering of land-to-ocean fluxes: from natural Holocene variations to Anthropocene – Meybeck & Vörösmarty (2005) “The evolution of river systems and their related fluxes is considered at various time scales: (i) over the last 18 000 years, under climatic variability control, (ii) over the last 50 to 200 years (Anthropocene) due to direct human impacts. Natural Holocene variations in time and space depend on (i) land-to-ocean connections (endorheism, glacial cover, exposure of continental shelf); (ii) types of natural fluvial filters (e.g., wetlands, lakes, floodplains, estuaries). Anthropocene changes concern (i) land–ocean connection (e.g., partial to total runoff reduction resulting from water management), (ii) modification and removal of natural filters, (iii) creation of new filters, particularly irrigated fields and reservoirs, (iv) acceleration and/or development of material sources from human activities. The total river basin area directly affected by human activities is of the same order of magnitude (>40 Mkm2) as the total area affected over the last 18 000 years. A tentative analysis of 38 major river systems totaling 55 Mkm2 is proposed for several criteria: (i) trajectories of Holocene evolution, (ii) occurrence of natural fluvial filters, (iii) present-day fluvial filters: most river basins are unique. Riverine fluxes per unit area are characterized by hot spots that exceed the world average by one order of magnitude. At the Anthropocene (i.e., since 1950), many riverine fluxes have globally increased (sodium, chloride, sulfate, nitrogen, phosphorous, heavy metals), others are stable (calcium, bicarbonate, sediments) or likely to decrease (dissolved silica). Future trajectories of river fluxes will depend on the balance between increased sources of material (e.g., soil erosion, pollution, fertilization), water abstraction for irrigation and the modification of fluvial filters, particularly the occurrence of reservoirs that already intercept half of the water and store at least 30% of river sediment fluxes. In some river systems, retention actually exceeds material production and river fluxes are actually decreasing. These trajectories are specific to each river and to each type of river material. Megacities, mining and industrial districts can be considered as hot spots of contaminants fluxes, while major reservoirs are global-scale sinks for all particulates. Global picture should therefore be determined at a fine resolution, since regional differences in Anthropocene evolution of river fluxes may reach one order of magnitude, as illustrated for total nitrogen.” Michel Meybeck, Charles Vörösmarty, Comptes Rendus Geoscience, Volume 337, Issues 1–2, January–February 2005, Pages 107–123, http://dx.doi.org/10.1016/j.crte.2004.09.016.

Global analysis of river systems: from Earth system controls to Anthropocene syndromes – Meybeck (2003) “Continental aquatic systems from rivers to the coastal zone are considered within two perspectives: (i) as a major link between the atmosphere, pedosphere, biosphere and oceans within the Earth system with its Holocene dynamics, and (ii) as water and aquatic biota resources progressively used and transformed by humans. Human pressures have now reached a state where the continental aquatic systems can no longer be considered as being controlled by only Earth system processes, thus defining a new era, the Anthropocene. Riverine changes, now observed at the global scale, are described through a first set of syndromes (flood regulation, fragmentation, sediment imbalance, neo–arheism, salinization, chemical contamination, acidification, eutrophication and microbial contamination) with their related causes and symptoms. These syndromes have direct influences on water uses, either positive or negative. They also modify some Earth system key functions such as sediment, water, nutrient and carbon balances, greenhouse gas emissions and aquatic biodiversity. Evolution of river syndromes over the past 2000 years is complex: it depends upon the stages of regional human development and on natural conditions, as illustrated here for the chemical contamination syndrome. River damming, eutrophication and generalized decrease of river flow due to irrigation are some of the other global features of river changes. Future management of river systems should also consider these long–term impacts on the Earth system.” Michel Meybeck, Phil. Trans. R. Soc. Lond. B 29 December 2003 vol. 358 no. 1440 1935-1955, doi: 10.1098/rstb.2003.1379. [Full text]

Geology of mankind – Crutzen (2002) “For the past three centuries, the effects of humans on the global environment have escalated. Because of these anthropogenic emissions of carbon dioxide, global climate may depart significantly from natural behaviour for many millennia to come. It seems appropriate to assign the term ‘Anthropocene’ to the present, in many ways human-dominated, geological epoch, supplementing the Holocene — the warm period of the past 10–12 millennia. The Anthropocene could be said to have started in the latter part of the eighteenth century, when analyses of air trapped in polar ice showed the beginning of growing global concentrations of carbon dioxide and methane.” Paul J. Crutzen, Nature 415, 23 (3 January 2002) | doi:10.1038/415023a. [Full text]

On the history of humans as geomorphic agents – Hooke (2000) “The human population has been increasing exponentially. Simultaneously, as digging sticks and antlers have given way to wooden plows, iron spades, steam shovels, and today’s huge excavators, our ability and motivation to modify the landscape by moving earth in construction and mining activities have also increased dramatically. As a consequence, we have now become arguably the premier geomorphic agent sculpting the landscape, and the rate at which we are moving earth is increasing exponentially. As hunter-gatherer cultures were replaced by agrarian societies to feed this expanding population, erosion from agricultural fields also, until recently, increased steadily. This constitutes an unintended additional human impact on the landscape.” Roger LeB. Hooke, Geology September, 2000 v. 28, no. 9, p. 843-846, doi: 10.1130/​0091-7613(2000)​28​2.0.CO;2. [Full text]

L’éxigence idéaliste et le fait de l’évolution – Le Roy (1927) A book where term “Noosphere” is used for Anthropocene. E. W. Berry, Science, New Series, Vol. 64, No. 1644 (Jul. 2, 1926), p. 16, DOI: 10.2307/1651728.

The Term Psychozoic – Berry (1926) No abstract. E. W. Berry, Science, New Series, Vol. 64, No. 1644 (Jul. 2, 1926), p. 16, DOI: 10.2307/1651728.

Elements of Geology – Le Conte (1879) A book where term “Psychozoic” is used for Anthropocene. Le Conte, J. Elements of Geology; D. Appleton & Co: New York, 1879. [Full text]

Corsa di Geologia – Stoppani (1873) A book where term “anthropozoic” is used for Anthropocene. From Crutzen (2002): “Mankind’s growing influence on the environment was recognized as long ago as 1873, when the Italian geologist Antonio Stoppani spoke about a “new telluric force which in power and universality may be compared to the greater forces of earth,” referring to the “anthropozoic era”.” Stoppani, A. Corsa di Geologia; Milan, 1873.