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The Anthropocene by the Numbers: A Quantitative Snapshot of Humanity's Influence on the Planet

Chure, Griffin and Banks, Rachel A. and Flamholz, Avi I. and Sarai, Nicholas S. and Kamb, Mason and Lopez-Gomez, Ignacio and Bar-On, Yinon M. and Milo, Ron and Phillips, Rob (2021) The Anthropocene by the Numbers: A Quantitative Snapshot of Humanity's Influence on the Planet. . (Unpublished)

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The presence and action of humans on Earth has exerted a strong influence on the evolution of the planet over the past ≈ 10,000 years, the consequences of which are now becoming broadly evident. Despite a deluge of tightly-focused and necessarily technical studies exploring each facet of "human impacts" on the planet, their integration into a complete picture of the human-Earth system lags far behind. Here, we quantify twelve dimensionless ratios which put the magnitude of human impacts in context, comparing the magnitude of anthropogenic processes to their natural analogues. These ratios capture the extent to which humans alter the terrestrial surface, hydrosphere, biosphere, atmosphere, and biogeochemistry of Earth. In almost all twelve cases, the impact of human processes rivals or exceeds their natural counterparts. The values and corresponding uncertainties for these impacts at global and regional resolution are drawn from the primary scientific literature, governmental and international databases, and industry reports. We present this synthesis of the current "state of affairs" as a graphical snapshot designed to be used as a reference. Furthermore, we establish a searchable database termed the Human Impacts Database (this http URL) which houses all quantities reported here and many others with extensive curation and annotation. While necessarily incomplete, this work collates and contextualizes a set of essential numbers summarizing the broad impacts of human activities on Earth's atmosphere, land, water, and biota.

Item Type:Report or Paper (Discussion Paper)
Related URLs:
URLURL TypeDescription Paper
http://www.anthroponumbers.orgRelated ItemHuman Impacts Database
Chure, Griffin0000-0002-2216-2057
Banks, Rachel A.0000-0003-2028-2925
Flamholz, Avi I.0000-0002-9278-5479
Sarai, Nicholas S.0000-0002-4655-0038
Lopez-Gomez, Ignacio0000-0002-7255-5895
Bar-On, Yinon M.0000-0001-8477-609X
Milo, Ron0000-0003-1641-2299
Phillips, Rob0000-0003-3082-2809
Additional Information:Attribution 4.0 International (CC BY 4.0). We are incredibly grateful for the generosity of a wide array of experts for their advice, suggestions, and criticism of this work. Specifically, we thank Suzy Beeler, Lars Bildsten, Justin Bois, Chris Bowler, Matthew Burgess, Ken Caldeira, Jörn Callies, Sean B. Carroll, Ibrahim Cissé, Joel Cohen, Michelle Dan, Bethany Ehlmann, Gidon Eshel, Paul Falkowski, Daniel Fisher, Thomas Frederikse, Neil Fromer, Eric Galbraith, Lea Goentoro, Evan Groover, John Grotzinger, Soichi Hirokawa, Greg Huber, Christina Hueschen, Bob Jaffe, Elizabeth Kolbert, Thomas Lecuit, Raphael Magarik, Jeff Marlow, Brad Marston, Jitu Mayor, Elliot Meyerowitz, Lisa Miller, Dianne Newman, Luke Oltrogge, Nigel Orme, Victoria Orphan, Marco Pasti, Pietro Perona, Noam Prywes, Stephen Quake, Hamza Raniwala, Manuel Razo-Mejia, Thomas Rosenbaum, Benjamin Rubin, Alex Rubinsteyn, Shyam Saladi, Tapio Schneider, Murali Sharma, Alon Shepon, Arthur Smith, Matthieu Talpe, Wati Taylor, Julie Theriot, Tadashi Tokieda, Cat Triandifillou, Sabah Ul-Hasan, Tine Valencic, and Ned Wingreen. We also thank Yue Qin for sharing data related to global water consumption. Many of the topics in this work began during the Applied Physics 150C course taught at Caltech during the early days of the COVID-19 pandemic. This work was supported by the Resnick Sustainability Institute at Caltech and the Schwartz-Reisman Collaborative Science Program at the Weizmann Institute of Science.
Group:Resnick Sustainability Institute
Funding AgencyGrant Number
Resnick Sustainability InstituteUNSPECIFIED
Weizmann Institute of ScienceUNSPECIFIED
Record Number:CaltechAUTHORS:20210302-081003409
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:108264
Deposited By: Tony Diaz
Deposited On:02 Mar 2021 18:38
Last Modified:02 Mar 2021 18:38

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