Environment: Pinning down the start of the
Anthropocene
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Nature
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Environmental sciences
Embargo
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London: Wednesday 11 March 2015 18:00 (GMT)
New York: Wednesday 11 March 2015 14:00 (EDT)
Tokyo: Thursday 12 March 2015 03:00 (JST)
Sydney: Thursday 12 March 2015 05:00 (AEDT)
Two potential dates that could mark the start of the Anthropocene, a suggested new epoch
that reflects the influence of human activity on the global environment, are proposed as the
more likely markers for this epoch in a Perspective in this week’s Nature. The authors
postulate that environmental impacts associated with the first arrival of Europeans in the
Americas, or the radioactive fallout associated with nuclear bomb testing could be defining
markers of the new epoch.
There is no formal consensus on when the Anthropocene Epoch may have started and
defining the beginning of the Anthropocene as a geologic time unit requires locating a global
marker that can be seen in the geological record. Simon Lewis and Mark Maslin assess a
range of signatures in the geological record that could conform to these criteria. They suggest
that very early human activity, such as the use of fire and the origins of farming or certain
historic events, such as the Industrial Revolution, can likely be rejected as suitable markers.
Instead, they propose two likely markers to define the start of the Anthropocene. One such
marker is the New–Old World collision — the resulting decline in human numbers and
changes in farming activities might be reflected in a decline in atmospheric carbon dioxide
recorded in ice cores in 1610 and supported by, for example, the global spread of food crops
(the pollen of which may be well-preserved in sediments). The other proposed likely marker
to define the start of the Anthropocene is the spike in radionuclide recorded in various
deposits in 1964.
The authors note that these events paint different pictures of the defining impacts of human
activity on the environment, and if formally established, would affect the perception of the
relationship between humans and the Earth.
An accompanying News Feature explores the debate over whether and how to define the
Anthropocene as a new geological epoch.
Article and author details
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Defining the Anthropocene
Corresponding Author
Simon Lewis (University College London, UK)
Email: s.l.Lewis@ucl.ac.uk, Tel: +44 113 34 33337
DOI
10.1038/nature14258
Online paper*
http://dx.doi.org/10.1038/nature14258
* Please link to the article in online versions of your report (the URL will go live after the embargo
ends).