Mass deaths in the Americas signaled start of the Anthropocene Epoch

The atmosphere recorded the mass death, slavery and warfare that followed 1492. The death by smallpox and warfare of an estimated 50 million native Americans—as well as the enslavement of Africans to work in the newly depopulated Americas—allowed forests to grow in former farmland. By 1610, the growth of all those trees had sucked enough carbon dioxide out of the sky to cause a drop of at least seven parts per million in atmospheric concentrations of the most prominent greenhouse gas and start a little ice age. Based on that dramatic shift, 1610 should be considered the start date of a new, proposed geologic epoch — the Anthropocene, or recent age of humanity — according to the authors of a new study…

Simon Lewis and Mark Maslin, a geologist at UCL, dub the decrease in atmospheric carbon dioxide the “Orbis spike,” from the Latin for world, because after 1492 human civilization has progressively globalized. They make the case that human impacts on the planet have been dramatic enough to warrant formal recognition of the Anthropocene epoch and that the Orbis spike should serve as the marker of the start of this new epoch in a paper published in Nature on March 12…

The Anthropocene is not a new idea. As far back as the 18th century, the first scientific attempt to lay out a chronology of Earth’s geologic history ended with a human epoch. By the 19th century, the idea was commonplace, appearing as the Anthropozoic (“human life rocks”) or the “Era of Man” in geology textbooks. But by the middle of the 20th century, the idea of the Holocene—a word which means “entirely recent” in Greek and designates the most recent period in which the great glacial ice sheets receded — had come to dominate, and incorporated the idea of humans as an important element of the current epoch but not the defining one.

That idea is no longer sufficient, according to scientists ranging from geologists to climatologists. Human impacts have simply grown too large, whether it’s the flood of nitrogen released into the world by the invention of the so-called Haber-Bosch process for wresting the vital nutrient from the air or the fact that civilization now moves more earth and stone than all the world’s rivers put together…

The CO2 drop coincides with what climatologists call the Little Ice Age. That cooling event may have been tied to regenerated forests and other plants growing on some 50 million hectares of land abandoned by humans after the mass death brought on by disease and warfare, Lewis and Maslin suggest. And it wasn’t just the death of millions of Americans, as many as three-quarters of the entire population of two continents. The enslavement (or death) of as many as 28 million Africans for labor in the new lands also may have added to the climate impact. The population of the regions of northwestern Africa most affected by the slave trade did not begin to recover until the end of the 19th century. In other words, from 1600 to 1900 or so swathes of that region may have been regrowing forest, enough to draw down CO2, just like the regrowth of the Amazon and the great North American woods, though this hypothesis remains in some dispute…

The changes wrought by humans over the course of the last several centuries, if not longer, will echo in the future, whether in the form of transplanted species, like earthworms or cats, crop pollen in lake sediments or even entire fossilized cities. Still, whether the Anthropocene started tens, hundreds or thousands of years ago, it accounts for a minute fraction of Earth’s history. And this new epoch could end quickly or endure through millennia, depending on the choices our species makes now. “Embracing the Anthropocene reverses 500 years of scientific discoveries that have made humans more and more insignificant,” Maslin notes. “We argue that Homo sapiens are central to the future of the only place where life is known to exist.”

Lewis and Maslin are scientists and, as such, have submitted their study for peer review. From the viewpoint of a lifetime student of science this sounds pretty reasonable. I look forward to reading some of the discussion to see where it all leads. Unless you, too, do that – this will be nothing more than a passing footnote to the overwhelming body of climate science thoroughly vetted and endorsed by the science community worldwide – and completely ignored except to revile as a commie plot by the ignoranuses inhabiting Congress and staffing the Koch Bros Legions.

American mass media being what it is – the only ongoing journalistic interest will come from that narrow band of the American Left that inhabits the danger zone beyond The Beltway and network/cable TV safety net. Perhaps, some time in the vaguely distant future when science is considered – along with civics – a source of enlightenment for Americans, the term will be allowed in public.

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2 thoughts on “Mass deaths in the Americas signaled start of the Anthropocene Epoch

  1. Koyaanisqatsi says:

    “H7N9 bird flu has the makings of a pandemic virus, scientists warn” http://www.latimes.com/science/sciencenow/la-sci-sn-h7n9-bird-flu-china-spread-pandemic-20150311-story.html “Scientists in China have identified an influenza virus that they say has the potential to spread around the world, sickening and killing people whose immune systems have never faced a threat like it. “H7N9 viruses should be considered as a major candidate to emerge as a pandemic strain in humans,” they wrote in a study {link} published Wednesday by the journal Nature.

  2. Pantropologist says:

    “NASA space probes have detected a massive, human-made ‘barrier’ surrounding Earth, and tests have confirmed that it’s actually having an effect on space weather far beyond our planet’s atmosphere. That means we’re not just changing Earth so severely, scientists are calling for a whole new geological epoch to be named after us – our activities have been changing space too. But the good news is that unlike our influence on the planet itself, that humongous bubble we created out in space is actually working in our favor.” https://www.sciencealert.com/nasa-space-probes-have-detected-a-human-made-barrier-shrouding-earth “Very Low Frequency (VLF) radio communications, have become far more common now than in the 60s, and the team at NASA confirmed that they can influence how and where certain particles in space move about. In other words, thanks to VLF, we now have anthropogenic (or human-made) space weather.”
    NASA also reports that in addition to the artificial radiation belts created by nuclear explosions in the atmosphere, “other anthropogenic impacts on the space environment include chemical release experiments, high-frequency wave heating of the ionosphere and the interaction of VLF waves with the radiation belts.”

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