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Geologists are not the most radical or wild-eyed of scientists. In keeping with the rocks and strata they study, they tend to think in terms of millions or billions of years, and changes that occur, let us say, glacially.
So when the International Union of Geological Sciences announces that it's in the process of formalizing the demise of the Holocene Epoch, the climatic and geological cradle in which civilization has been developing for the past 11,000 years or so, and usher us into the uncharted, unpredictable, human-dominated Anthropocene, we'd best take notice.
Millions of years of sedimentary layers in the Grand Canyon
Credit: USGS
The Holocene is the climatically benign epoch in which all of human civilization has unfolded. In the year 2000, Nobel prize winning atmospheric chemist Paul Crutzen and biologist Eugene Stoermer floated the idea that human activities rather than natural processes were now dominating Earth's biology and geology, and proposed that this be recognized as a new geological epoch, the Anthropocene. After several years of deliberations, The Working Group on the 'Anthropocene' says it's time to formalize that idea.
Plastic Earth/Credit Univ. of Leicester
The Working Group will present its findings and recommendations to the 35th International Geological Congress, currently meeting in Cape Town, South Africa. That will lead to a formal proposal to the Subcommission on Quaternary Stratigraphy, and, if approved, on to the International Commission on Stratigraphy, with final ratification in the hands of the Executive Committee of the International Union of Geological Sciences.
The process, including further research to settle on one or more "golden spikes"--locations where the stratigraphic signature of human impacts is clearest--could take several years.
Clearly, it's no small thing to end one geological epoch and start another. "The Time Scale is the backbone of our science," says paleobiologist Jan Zalasiewicz, a member of the Working Group. "We do not treat it lightly at all." However, the Working Group has amassed convincing evidence that the Anthropocene is real.
They note that since the middle of the 20th Century, the Earth System has seen markedly accelerated erosion and sedimentation, major perturbations to the cycles of carbon, nitrogen, phosphorous and other elements, significant changes to climate and sea level, unprecedented changes in the distribution of plants and animals, and a marked reduction in biodiversity, all caused by human activities.
From the purely geological point of view, these changes have left clear and permanent signals in recent strata, including the presence of plastic, aluminum, concrete, fly ash and radioactive fallout.
Of the 35 members of the Working Group, 34 agreed that the Anthropocene is stratigraphically real, and 30 concurred that it should formally be made a new Epoch within the Geological Time Scale.
Of course this formal recognition that we are living in an epoch dominated more by humans than by nature goes far beyond the discipline of geology. This recognition that our combined activities are impacting not just the atmosphere and climate, but the very rocks beneath our feet, tells us in no uncertain terms that the time for climate-change denial is long past and the time for concerted action overdue.
"The Earth System has, in a a real sense, begun a new trajectory," says Zalasiewicz. "The Anthropocene - beyond its formal expression in geology - seems to be useful to people as a means of grasping the scale in time and space of what is going on, and of linking myriad human activities with with the wide range of impacts on the natural world. Hopefully it may help us understand, control and adapt to those impacts."
You can read about a visionary call for concerted action to create a sustainable world here.
You can view a detailed presentation on the Anthropocene by Prof. Zalasiewicz at this URL.
You can read here an update from 1/15/18 about how scientists worldwide are homing in on an official "golden spike" that will mark the onset of the anthropocene, probably between 1952 and 1955. This comment is worth noting:
Professor Mark Williams [a geologist at the University of Leicester] said: “The range of environments we are working with is remarkable – from polar ice and snow layers to deep lake and sea floors to the skeletons of reef corals and stalactites in caves. The fact that signals of the Anthropocene are so sharply visible in all of these shows just how pervasive human impact has been on the planet in post-war times.”
The process, including further research to settle on one or more "golden spikes"--locations where the stratigraphic signature of human impacts is clearest--could take several years.
Clearly, it's no small thing to end one geological epoch and start another. "The Time Scale is the backbone of our science," says paleobiologist Jan Zalasiewicz, a member of the Working Group. "We do not treat it lightly at all." However, the Working Group has amassed convincing evidence that the Anthropocene is real.
They note that since the middle of the 20th Century, the Earth System has seen markedly accelerated erosion and sedimentation, major perturbations to the cycles of carbon, nitrogen, phosphorous and other elements, significant changes to climate and sea level, unprecedented changes in the distribution of plants and animals, and a marked reduction in biodiversity, all caused by human activities.
From the purely geological point of view, these changes have left clear and permanent signals in recent strata, including the presence of plastic, aluminum, concrete, fly ash and radioactive fallout.
Hydrogen bomb blast over Bikini Atoll, March 1, 1954, one of many
nuclear blasts whose fallout contributes to the Anthropocene signal
Credit: Wikipedia
Of the 35 members of the Working Group, 34 agreed that the Anthropocene is stratigraphically real, and 30 concurred that it should formally be made a new Epoch within the Geological Time Scale.
Of course this formal recognition that we are living in an epoch dominated more by humans than by nature goes far beyond the discipline of geology. This recognition that our combined activities are impacting not just the atmosphere and climate, but the very rocks beneath our feet, tells us in no uncertain terms that the time for climate-change denial is long past and the time for concerted action overdue.
"The Earth System has, in a a real sense, begun a new trajectory," says Zalasiewicz. "The Anthropocene - beyond its formal expression in geology - seems to be useful to people as a means of grasping the scale in time and space of what is going on, and of linking myriad human activities with with the wide range of impacts on the natural world. Hopefully it may help us understand, control and adapt to those impacts."
You can read about a visionary call for concerted action to create a sustainable world here.
You can view a detailed presentation on the Anthropocene by Prof. Zalasiewicz at this URL.
You can read here an update from 1/15/18 about how scientists worldwide are homing in on an official "golden spike" that will mark the onset of the anthropocene, probably between 1952 and 1955. This comment is worth noting:
Professor Mark Williams [a geologist at the University of Leicester] said: “The range of environments we are working with is remarkable – from polar ice and snow layers to deep lake and sea floors to the skeletons of reef corals and stalactites in caves. The fact that signals of the Anthropocene are so sharply visible in all of these shows just how pervasive human impact has been on the planet in post-war times.”
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