...a formal decision by the International Commission on Stratigraphy is years away. In the meantime, a subsidiary body, the Anthropocene Working Group (because of my early writings, I’m a lay member), has moved substantially from asking whether such a transition has occurred to deciding when.In a paper published online this week by the journal Quaternary International, 26 members of the working group point roughly to 1950 as the starting point, indicated by a variety of markers, including the global spread of carbon isotopes from nuclear weapon detonations starting in 1945 and the mass production and disposal of plastics. (About six billion tons have been made, with a billon of those tons dumped and a substantial amount spread around the world’s seas.)
For a series of charts showing the salience of that dating, go to the website of the IGBP (International Geosphere-Biosphere Program). From that site:
About one half of the global population now lives in urban areas and about third of the global population has completed the transition from agrarian to industrial societies. This shift is evident in several indicators. Most of the post-2000 rise in fertilizer consumption, paper production and motor vehicles has occurred in the non-OECD world.Coinciding with the publication of the Great Acceleration indicators, researchers also led by Professor Steffen have published a new assessment of the concept of “planetary boundaries” in the journal Science. The international team of 18 scientists identified two core planetary boundaries: climate change and “biosphere integrity”. Altering either could “drive the Earth System into a new state.” The planetary boundaries concept, first published in 2009, identifies nine global priorities relating to human-induced changes to the environment. The new research confirms many of the boundaries and provides updated analysis and quantification for several of them including phosphorus and nitrogen cycles, land use and biodiversity.
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