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Goodbye, Anthropocene? Scientists vote against new epoch – CBC News

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For the past two decades, geologists have wrestled with whether humans have changed the planet enough to kick off a completely new epoch in geological time called the Anthropocene. Now, a subcommittee of Earth scientists has reportedly made a decision: No, we haven’t.

The results mean we’re still living in the Holocene, an epoch that started with the end of the last ice age 11,700 years ago.

The Subcommission on Quaternary Stratigraphy (SQS) voted on the proposed Anthropocene epoch over the past month, and the results were released to subcommittee members on Tuesday, the New York Times reported. The newspaper saw the internal document listing the votes: 12 against, four in favour and two abstentions.

The SQS is a constituent body of the International Commission on Stratigraphy (ICS), which decides what divisions are included on the official geologic time scale, and when they begin and end.

A brief history of the Anthropocene

The proposal for the Anthropocene epoch was first popularized by the Dutch Nobel-prize-winning chemist, Paul Crutzen, in the early 2000s. In 2009, the ICS convened a group of geologists, paleontologists and other scientists called the Anthropocene Working Group.

“We were asked to determine whether or not there was evidence in the geologic record of that shift in the Earth system that this atmospheric chemist threw out there,” said Francine McCarthy, a professor of Earth sciences at Brock University in St. Catharines, Ont., who was a group member. “And our answer was a resounding yes.”

The scientists in the working group found evidence that the epoch started in 1950. That’s when they say human impact on the planet accelerated, as seen in plastics, elemental aluminum (which is found only as ores in nature), black carbon from fossil fuel combustion and plutonium from hydrogen bomb tests, chosen as the “primary” marker for the start of the Anthropocene.

Some of the best preserved evidence was found in layers of sediment at the bottom of Crawford Lake in Milton, Ont., which was named last year as the proposed “golden spike” marking the start of the new proposed epoch.

WATCH | This Ontario lake could help scientists define our next geological era:

This Ontario lake could help scientists define our next geological era

8 months ago

Duration 2:08

A group of scientists is pushing to have a new geological epoch declared, something that only happens every few million years, or longer. Named the ‘Anthropocene,’ they say it is driven by human activity.

‘Validity of the vote’ questioned

A statement from the Anthropocene Working Group emailed to CBC News on Tuesday said “there remain several issues that need to be resolved about the validity of the vote” and that until they’re resolved, “it would be inappropriate to talk directly on this matter at present.”

McCarthy said the group hasn’t received any feedback on the evidence that was voted on — not even in the New York Times article.

“At least I would have liked to have read in the article that they found this unconvincing,” she said.

Instead, subcommittee members pointed out that human impacts began well before 1950, with events such as the onset of agriculture or the Industrial Revolution.

What others scientists think

Some Canadian scientists who study the geological record in sediments and rocks aren’t surprised by the results of the vote.

Joe Desloges, a professor in the geography and Earth sciences departments at the University of Toronto, said scientists have been debating the Anthropocene for well over a decade. “Which means it’s not a slam dunk.”

He said he hadn’t anticipated the big majority of “no” votes. But he added that the geological time scale is typically set based on records in solid rocks, not sediments like those in Crawford Lake. “I think people are kind of skeptical about the permanency of it.”

An aerial view of a pear-shaped lake surrounded by forest
Crawford Lake is shown in Milton, Ont., in July 2023. The lake has been chosen as the ‘golden spike’ to mark the start of a proposed new epoch, the Anthropocene. (Cole Burston/The Canadian Press)

Boundaries between epochs also tend to represent truly massive geological change. “Our last boundary, between the Holocene and the Pleistocene, was almost one-third of this planet being covered by ice,” Desloges said. “The sheer magnitude and scale of that tends to be what people are looking for when they define these boundaries.”

John-Paul Zonneveld, a professor of Earth sciences who studies the boundary between the Permian and Triassic epochs at the University of Alberta in Edmonton, said he thinks the subcommittee made the right decision.

The events that kick off a new epoch typically take place over millions of years, he said. That was the case for the Permian-Triassic boundary, which involved a mass extinction in two events — one that happened before and one that happened after the official line between the two epochs.

The 11,700 years between the Holocene and the proposed Anthropocene would be a “flip of an eyelash” — so short as to be impossible to see on that time scale, Zonneveld said. 

Humans’ huge impact on the planet remains clear

All three scientists interviewed for this article emphasized that regardless of the vote, humans have changed this planet in huge ways.

Zonneveld said he understands why there is so much debate about the Anthropocene.

“It does bring attention to global change, global warming. These are important issues, absolutely. But from a stratigraphic standpoint, does it help in any way? No.”

Brock University’s McCarthy said when she first started working at Crawford Lake, she wasn’t convinced it would be a great record of humanity’s impact, but over time, seeing the evidence pile up, “I became a convert.”

She said seeing a new line on the geological time scale isn’t what she wants the most. “My major goal is to have as many humans pay attention to the data as humanly possible.”

A finger points to a spot on a striped cylinder
Francine McCarthy of Brock University points at the layer of sediment in a Crawford Lake mud core that shows the global plutonium spike from nuclear weapons testing that marks the beginning of the proposed Anthropocene epoch. Crawford Lake is one of nine sites around the world vying to become the official boundary layer that best represents the global transition from the Holocene epoch to the Anthropocene. (Mercury Films Inc./Nick de Pencier)

What does this mean for the Anthropocene?

The debate over the Anthropocene isn’t over yet. As of Tuesday, the results of the vote hadn’t been officially announced.

And the subcommittee hadn’t dealt with the second part of the Anthropocene Working Group’s proposal — that the first subdivision, or age of the Anthropocene, be called the Crawfordian, after Crawford Lake.

Could the ICS still consider a new age called the Crawfordian, even if it’s not part of a new epoch? McCarthy said she doesn’t know. “I hope that they do,” she said.

Desloges said he thinks the debate over the Anthropocene will continue, and he noted that the Earth has 4.5 billion years of history behind it. “If anyone is in a rush to identify a new epoch, we’ve got a bit of time.”

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Here’s how Helene and other storms dumped a whopping 40 trillion gallons of rain on the South

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More than 40 trillion gallons of rain drenched the Southeast United States in the last week from Hurricane Helene and a run-of-the-mill rainstorm that sloshed in ahead of it — an unheard of amount of water that has stunned experts.

That’s enough to fill the Dallas Cowboys’ stadium 51,000 times, or Lake Tahoe just once. If it was concentrated just on the state of North Carolina that much water would be 3.5 feet deep (more than 1 meter). It’s enough to fill more than 60 million Olympic-size swimming pools.

“That’s an astronomical amount of precipitation,” said Ed Clark, head of the National Oceanic and Atmospheric Administration’s National Water Center in Tuscaloosa, Alabama. “I have not seen something in my 25 years of working at the weather service that is this geographically large of an extent and the sheer volume of water that fell from the sky.”

The flood damage from the rain is apocalyptic, meteorologists said. More than 100 people are dead, according to officials.

Private meteorologist Ryan Maue, a former NOAA chief scientist, calculated the amount of rain, using precipitation measurements made in 2.5-mile-by-2.5 mile grids as measured by satellites and ground observations. He came up with 40 trillion gallons through Sunday for the eastern United States, with 20 trillion gallons of that hitting just Georgia, Tennessee, the Carolinas and Florida from Hurricane Helene.

Clark did the calculations independently and said the 40 trillion gallon figure (151 trillion liters) is about right and, if anything, conservative. Maue said maybe 1 to 2 trillion more gallons of rain had fallen, much if it in Virginia, since his calculations.

Clark, who spends much of his work on issues of shrinking western water supplies, said to put the amount of rain in perspective, it’s more than twice the combined amount of water stored by two key Colorado River basin reservoirs: Lake Powell and Lake Mead.

Several meteorologists said this was a combination of two, maybe three storm systems. Before Helene struck, rain had fallen heavily for days because a low pressure system had “cut off” from the jet stream — which moves weather systems along west to east — and stalled over the Southeast. That funneled plenty of warm water from the Gulf of Mexico. And a storm that fell just short of named status parked along North Carolina’s Atlantic coast, dumping as much as 20 inches of rain, said North Carolina state climatologist Kathie Dello.

Then add Helene, one of the largest storms in the last couple decades and one that held plenty of rain because it was young and moved fast before it hit the Appalachians, said University of Albany hurricane expert Kristen Corbosiero.

“It was not just a perfect storm, but it was a combination of multiple storms that that led to the enormous amount of rain,” Maue said. “That collected at high elevation, we’re talking 3,000 to 6000 feet. And when you drop trillions of gallons on a mountain, that has to go down.”

The fact that these storms hit the mountains made everything worse, and not just because of runoff. The interaction between the mountains and the storm systems wrings more moisture out of the air, Clark, Maue and Corbosiero said.

North Carolina weather officials said their top measurement total was 31.33 inches in the tiny town of Busick. Mount Mitchell also got more than 2 feet of rainfall.

Before 2017’s Hurricane Harvey, “I said to our colleagues, you know, I never thought in my career that we would measure rainfall in feet,” Clark said. “And after Harvey, Florence, the more isolated events in eastern Kentucky, portions of South Dakota. We’re seeing events year in and year out where we are measuring rainfall in feet.”

Storms are getting wetter as the climate change s, said Corbosiero and Dello. A basic law of physics says the air holds nearly 4% more moisture for every degree Fahrenheit warmer (7% for every degree Celsius) and the world has warmed more than 2 degrees (1.2 degrees Celsius) since pre-industrial times.

Corbosiero said meteorologists are vigorously debating how much of Helene is due to worsening climate change and how much is random.

For Dello, the “fingerprints of climate change” were clear.

“We’ve seen tropical storm impacts in western North Carolina. But these storms are wetter and these storms are warmer. And there would have been a time when a tropical storm would have been heading toward North Carolina and would have caused some rain and some damage, but not apocalyptic destruction. ”

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Follow AP’s climate coverage at https://apnews.com/hub/climate

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Follow Seth Borenstein on Twitter at @borenbears

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Associated Press climate and environmental coverage receives support from several private foundations. See more about AP’s climate initiative here. The AP is solely responsible for all content.

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‘Big Sam’: Paleontologists unearth giant skull of Pachyrhinosaurus in Alberta

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It’s a dinosaur that roamed Alberta’s badlands more than 70 million years ago, sporting a big, bumpy, bony head the size of a baby elephant.

On Wednesday, paleontologists near Grande Prairie pulled its 272-kilogram skull from the ground.

They call it “Big Sam.”

The adult Pachyrhinosaurus is the second plant-eating dinosaur to be unearthed from a dense bonebed belonging to a herd that died together on the edge of a valley that now sits 450 kilometres northwest of Edmonton.

It didn’t die alone.

“We have hundreds of juvenile bones in the bonebed, so we know that there are many babies and some adults among all of the big adults,” Emily Bamforth, a paleontologist with the nearby Philip J. Currie Dinosaur Museum, said in an interview on the way to the dig site.

She described the horned Pachyrhinosaurus as “the smaller, older cousin of the triceratops.”

“This species of dinosaur is endemic to the Grand Prairie area, so it’s found here and nowhere else in the world. They are … kind of about the size of an Indian elephant and a rhino,” she added.

The head alone, she said, is about the size of a baby elephant.

The discovery was a long time coming.

The bonebed was first discovered by a high school teacher out for a walk about 50 years ago. It took the teacher a decade to get anyone from southern Alberta to come to take a look.

“At the time, sort of in the ’70s and ’80s, paleontology in northern Alberta was virtually unknown,” said Bamforth.

When paleontogists eventually got to the site, Bamforth said, they learned “it’s actually one of the densest dinosaur bonebeds in North America.”

“It contains about 100 to 300 bones per square metre,” she said.

Paleontologists have been at the site sporadically ever since, combing through bones belonging to turtles, dinosaurs and lizards. Sixteen years ago, they discovered a large skull of an approximately 30-year-old Pachyrhinosaurus, which is now at the museum.

About a year ago, they found the second adult: Big Sam.

Bamforth said both dinosaurs are believed to have been the elders in the herd.

“Their distinguishing feature is that, instead of having a horn on their nose like a triceratops, they had this big, bony bump called a boss. And they have big, bony bumps over their eyes as well,” she said.

“It makes them look a little strange. It’s the one dinosaur that if you find it, it’s the only possible thing it can be.”

The genders of the two adults are unknown.

Bamforth said the extraction was difficult because Big Sam was intertwined in a cluster of about 300 other bones.

The skull was found upside down, “as if the animal was lying on its back,” but was well preserved, she said.

She said the excavation process involved putting plaster on the skull and wooden planks around if for stability. From there, it was lifted out — very carefully — with a crane, and was to be shipped on a trolley to the museum for study.

“I have extracted skulls in the past. This is probably the biggest one I’ve ever done though,” said Bamforth.

“It’s pretty exciting.”

This report by The Canadian Press was first published Sept. 25, 2024.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.

Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.

Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.

The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.

The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.

It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.

Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.

Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.

Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.

Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.

Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.

The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”

The Canadian Press. All rights reserved.

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