Marker Proposed for the Start of the Anthropocene Epoch: Canada's Crawford Lake (sciencedaily.com) 23
The University of Southampton has an announcement. Slashdot reader pyroclast shared this report from ScienceDaily:
Today an international team of researchers has chosen the location which best represents the beginnings of what could be a new geological epoch, the Anthropocene. The Anthropocene Working Group have put forward Crawford Lake, in Canada, as a Global Boundary Stratotype Section and Point (GSSP) for the Anthropocene.
A GSSP is an internationally agreed-upon reference point to show the start of a new geological period or epoch in layers of rock that have built up through the ages. It's been proposed by some geologists that we are now living in the Anthropocene — a new geological epoch in which human activity has become the dominant influence on the world's climate and environment. The concept has significant implications for how we consider our impact on the planet. But there is disagreement in the scientific community about when the Anthropocene began, how it is evidenced and whether human influence has been substantial enough to constitute a new geological age, which usually span millions of years. To help answer these questions, the International Commission on Stratigraphy (ICS) set up the Anthropocene Working Group.
"The sediments found at the bottom of Crawford Lake provide an exquisite record of recent environmental change over the last millennia," says Dr Simon Turner, Secretary of the Anthropocene Working Group from UCL. "Seasonal changes in water chemistry and ecology have created annual layers that can be sampled for multiple markers of historical human activity. It is this ability to precisely record and store this information as a geological archive that can be matched to historical global environmental changes which make sites such as Crawford Lake so important...."
Professor Andrew Cundy, Chair in Environmental Radiochemistry at the University of Southampton and member of the Anthropocene Working Group, explains: "The presence of plutonium gives us a stark indicator of when humanity became such a dominant force that it could leave a unique global 'fingerprint' on our planet. In nature, plutonium is only present in trace amounts. But in the early-1950s, when the first hydrogen bomb tests took place, we see an unprecedented increase and then spike in the levels of plutonium in core samples from around the world. We then see a decline in plutonium from the mid-1960s onwards when the Nuclear Test-Ban Treaty came into effect."
Other geological indicators of human activity include high levels of ash from coal-fired power stations, high concentrations of heavy metals, such as lead, and the presence of plastic fibres and fragments. These coincide with 'The Great Acceleration' — a dramatic surge across a range of human activity, from transportation to energy use, starting in the mid-20th century and continuing today.
"Evidence from the sites will now be presented to the International Commission on Stratigraphy, which will decide next year whether to ratify the Anthropocene as a new geological epoch."
A GSSP is an internationally agreed-upon reference point to show the start of a new geological period or epoch in layers of rock that have built up through the ages. It's been proposed by some geologists that we are now living in the Anthropocene — a new geological epoch in which human activity has become the dominant influence on the world's climate and environment. The concept has significant implications for how we consider our impact on the planet. But there is disagreement in the scientific community about when the Anthropocene began, how it is evidenced and whether human influence has been substantial enough to constitute a new geological age, which usually span millions of years. To help answer these questions, the International Commission on Stratigraphy (ICS) set up the Anthropocene Working Group.
"The sediments found at the bottom of Crawford Lake provide an exquisite record of recent environmental change over the last millennia," says Dr Simon Turner, Secretary of the Anthropocene Working Group from UCL. "Seasonal changes in water chemistry and ecology have created annual layers that can be sampled for multiple markers of historical human activity. It is this ability to precisely record and store this information as a geological archive that can be matched to historical global environmental changes which make sites such as Crawford Lake so important...."
Professor Andrew Cundy, Chair in Environmental Radiochemistry at the University of Southampton and member of the Anthropocene Working Group, explains: "The presence of plutonium gives us a stark indicator of when humanity became such a dominant force that it could leave a unique global 'fingerprint' on our planet. In nature, plutonium is only present in trace amounts. But in the early-1950s, when the first hydrogen bomb tests took place, we see an unprecedented increase and then spike in the levels of plutonium in core samples from around the world. We then see a decline in plutonium from the mid-1960s onwards when the Nuclear Test-Ban Treaty came into effect."
Other geological indicators of human activity include high levels of ash from coal-fired power stations, high concentrations of heavy metals, such as lead, and the presence of plastic fibres and fragments. These coincide with 'The Great Acceleration' — a dramatic surge across a range of human activity, from transportation to energy use, starting in the mid-20th century and continuing today.
"Evidence from the sites will now be presented to the International Commission on Stratigraphy, which will decide next year whether to ratify the Anthropocene as a new geological epoch."
Yes but... (Score:2)
Did they serve cake and ice cream?
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Did they serve cake and ice cream?
Ice cream is on the way out [cnn.com]. Having seen the prices for even low grade ice cream, it's no wonder.
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If I want ice cream then it's going to be Ben & Jerry's. Yeah it's expensive but nothing good is cheap.
I had settled on Tillamook when it was $4 or under a container, but it's over $6 now so no way. I'll do without until I find something else.
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Did it taste better because it was "organic"?
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If I want ice cream then it's going to be Ben & Jerry's
Enjoy it now. Who knows what will happen to the quality once they give the land for their headquarters back to the Native Americans.
Re: Yes but... (Score:1)
90% of everything is crap.
-- Theodore Sturgeon
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That article is interesting, but it doesn't really cover how a "pint" of ice cream is much less than it was: with all the air whipped into it, the quantity (measured by weight) has dropped, for the same size containers.
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with all the air whipped into it, the quantity (measured by weight) has dropped, for the same size containers.
It depends on how it's measured. If it's by weight, 48 ounces, then you are getting 48 ounces by weight. If it says 1.5 L, then you are getting 1.5 L which is the capacity of the container.
As a rule, the higher end ice creams have less air whipped into them. Store brand most likely has the maximum amount of air allowed by law which can be half the volume [wikipedia.org].
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It depends on how it's measured. If it's by weight, 48 ounces, then you are getting 48 ounces by weight. If it says 1.5 L, then you are getting 1.5 L which is the capacity of the container.
In the USA, it's sold by volume.
The Anthropocene is a joke epoch, but maybe useful (Score:3)
The idea of the Anthropocene as a geological ***epoch*** is a conceit showing mankind's self delusions of grandeur. Geological time is deep beyond all comprehension. If you were to run a 26.2-mile marathon spanning the entire retrospective sweep of Earth’s history in reverse, the first five-foot stride would land you two Ice Ages ago and more than 150,000 years before the whole history of human civilization. In other words, geologically and to a first approximation, all of recorded human history is irrelevant: a subliminally fast 5,000-year span that is over almost as soon as you first lift up your heel.
The only potential usefulness of the "Anthropocene" concept is as a tool to raise urgent awareness (already too late) of the perils of climate change.
But to the concepts behind the proposal, here is what traditional geological thinking has to say about it:
-- Whereas some epochs in Earth history stretch more than 40 million years, we are told this new epoch started as recently as 75 years ago, when atomic weapons began to dust the planet with an evanescence of strange radioisotopes. This is a laughably tiny amount of time that would barely even qualify to be designated an "event" in geologic terminology.
-- Geology typically deals with mile-thick packages of rock stacked up over tens of millions of years, wherein entire mountain ranges are born and weather away to nothing within a single unit of time, in which extremely precise rock dates — single-frame snapshots from deep time — can come with 50,000-year error bars, a span almost 10 times as long as all of recorded human history. If having an epoch shorter than an error bar seems strange, well, so is the Anthropocene proposal.
-- Plutonium is proposed here as the start of the Anthropocene's mark on the geologic record. Ignore plutonium for a moment, because even the longest-lived radioisotope from radioactive fallout, iodine-129, has a half-life of less than 16 million years. That is tiny in geologic time scales. If there were a nuclear holocaust in the Triassic, among warring prosauropods, we wouldn’t know about it today because no trace would remain.
-- The presence of plastic fibres and fragments is also offered as a possible marker of our impact. How about that instead? Indeed small samples from our tiny geologic stratum that interrupts mile-thick formations of otherwise normal rock might be detectable. However, a few thousand years — or even a few tens of thousands of years — will be virtually indistinguishable in the rocks a hundred million years hence. The clear-cutting of the rain forest to build roads and palm-oil plantations, the plowing of the seabed on a continental scale, the rapid changes to the ocean and atmosphere’s chemistry, and all the rest would appear ***simultaneous*** with the extinction of the woolly mammoth. To future geologists, the modern debate about whether the Anthropocene started 10 minutes ago or 10,000 years ago will be a bit like arguing with your spouse on your 50th wedding anniversary about which nanosecond you got married.
The following article is recommended reading to get a true grasp on the staggering time scale of deep geologic time and the arrogant folly of the idea of an Anthropocene epoch:
www theatlantic com /science/archive/2019/08/arrogance-anthropocene/595795/
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If "the "Anthropocene" concept is a tool to raise urgent awareness (already too late) of the perils of climate change" is a "conceit showing mankind's self delusions of grandeur", why isn't anthropomorphic climate change the same thing? There are no examples of weather events that are at all out of line with know historical weather or climate data. For the same reasons we aren't in a new era, we aren't in a new climate.
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You are partially correct. The idea that we are ruining the planet is also a human conceit. Anthropogenic climate change is only adversely affecting the habitability of the Earth for ourselves and thousands of our fellow species. But the Earth will continue just fine without us. And many other life forms will continue after we're gone.
In the deep geologic past, there have been periods where the climate was even more inhospitable than the worst that is coming from the atmospheric forcing we are currently und
There's a more fitting marker... (Score:2)
The Aral Sea. It existed for 11 millennia up to 1960 CE. Soon afterwards, the Soviet Union started monkeying around with its source waters, and by 2010, over 90% of its liquid surface area disappeared. What would be a more fitting geologic marker to usher in the anthropocene?