Tag: Anthropocene

Categories
Life Style

the Anthropocene is not an epoch, despite protest over vote

[ad_1]

Plastic bottles washed up on shore of a Carribean islanda`

Some geoscientists argue that humans have transformed the planet with plastic trash, radioactive debris and fossil-fuel emissions, among other things — and that the changes should be recognized with a new geological epoch.Credit: Mark Meredith/Getty

A high-profile battle over whether to designate the ‘Anthropocene’ as a new geological epoch has come to an end. On 20 March, the International Union of Geological Sciences (IUGS) — the final arbiter in the matter — announced it is upholding a decision made earlier this month by a group of geoscientists. That group voted on 4 March to reject a proposal that would have established the current era, in which humans are altering the planet, as a formal epoch in Earth’s geological timetable.

The IUGS decision effectively terminates a dramatic challenge to that earlier vote: the chair and a vice-chair of the Subcommission on Quaternary Stratigraphy (SQS), which held the vote, said it was illegitimate. Among other things, they said that 11 of the 16 SQS members who voted on the Anthropocene proposal were ineligible because they have been members of the subcommission for too long.

In a statement, the IUGS called the 4 March vote and its appeal “a difficult process” that was conducted “fully in accordance with the statutory requirements”. Stanley Finney, a stratigrapher at California State University, Long Beach, who is the IUGS secretary-general, told Nature that it was longstanding practice among these subcommissions to allow members who had overextended their terms to vote anyway. “You can’t just throw them off if you want something done,” he says.

The IUGS is the parent organization for the International Commission on Stratigraphy (ICS), to which the SQS belongs. “There is no further supreme court one can go to,” says Jan Zalasiewicz, a palaeontologist at the University of Leicester, UK, who is the SQS chair who protested the subcommission’s vote. “I have no immediate plans for a challenge.”

A tangled quest

The controversy underscores the long-running quest to bring the Anthropocene proposal to a vote, and the tangle of international geological organizations involved. In 2009, the SQS set up an Anthropocene working group to assess whether the current era of human-induced change should be codified as a new ‘stratigraphic unit’ in the geological time scale. After 15 years of discussion and exploration, the working group submitted its proposal last October, arguing that a new epoch should be established. Its start, the group said, should be marked by plutonium residue from hydrogen-bomb tests in 1952 appearing in Earth’s geology.

Under ICS rules, such a proposal would normally be discussed for a 30-day period and then voted on for another 30 days. Zalasiewicz says he and vice-chair Martin Head, a stratigrapher at Brock University in St Catharines, Canada, recused themselves from moderating the discussion because of conflicts of interest from their earlier participation in the Anthropocene working group. When the discussion period ended and other SQS members moved to vote on the proposal, Zalasiewicz and Head objected, saying that it had not been given serious consideration and that the vote was rushed.

Voting began in early February and ended on 4 March, with four SQS members voting in favour of establishing an Anthropocene epoch and 12 voting against it. Three people abstained and three did not vote, including Zalasiewicz and Head. The results of the vote were then approved by the full ICS and, as of today, the IUGS.

Participation on ICS subcommissions, which deal with different geological periods from the ancient to the modern, typically happens in four-year terms. Anyone who has been a member of a subcommission for more than 12 years is no longer a voting member, according to ICS statutes. Zalasiewicz says that this restriction applies to him, as well as to many other SQS members — and says that for this reason, the 4 March vote is illegitimate.

Stricter compliance

The discussion has prompted other ICS subcommissions to re-examine their membership rosters for people who might have passed the 12-year limit and thus are no longer eligible to vote, says Philip Gibbard, a geologist at the University of Cambridge, UK. More broadly, the IUGS has been working towards refreshing its committee membership more frequently, to increase gender, racial and geographic equity, Finney says.

David Harper, a palaeontologist at Durham University, UK, and current chair of the ICS, says that the commission will be enforcing stricter compliance on term limits going forward.

For his part, Zalasiewicz says he has been asked to step down as SQS chair and does not expect to be part of any ICS group going forward. He and other Anthropocene-epoch advocates are likely to continue their campaign in other venues, he says: “Another means will have to be found” to codify the Anthropocene as a concept outside of the official geological timescale.

Regardless of there being no formal Anthropocene epoch, the term will continue to be used in broad popular and scientific usage as the era of human-induced change. “As such, it will remain an invaluable descriptor in human-environment interactions,” the IUGS says.

[ad_2]

Source Article Link

Categories
Life Style

Are we in the Anthropocene yet?

[ad_1]

Researchers stand on a raft on the surface of Crawford Lake and pull up sediment core samples

Researchers are investigating plutonium traces in the sediment of Crawford Lake in Canada as a marker for the start of the Anthropocene.Credit: Peter Power/AFP/Getty

For 15 years, geologists have been involved in a complicated technical process to determine whether human impacts on Earth systems amount to a new geological epoch. Earlier this month, 12 members of a subgroup of one of their professional bodies, the International Commission on Stratigraphy (ICS), voted that the ‘Anthropocene’ is not a new epoch that would have ended the Holocene epoch, which started some 11,700 ago at the end of the last ice age. Four voted in favour of the proposed new epoch. Some members want to annul the vote because of disagreements about whether ICS rules were followed, including during the voting process.

News of the vote, and the ensuing controversy, has created both confusion and concern, including among those currently working on Anthropocene science. This confusion arises because the term is understood and widely used by scientists, as well as people outside research, to mean a time in Earth’s history when humans are having severe biophysical impacts on the planet.

The concept is used by researchers in natural sciences, engineering, humanities and social sciences; by authors of books on the topic, film-makers, editors of journals with Anthropocene in the title and, indeed, by the Nature Portfolio. In 2023, we launched a newsletter called ‘Nature Briefing: Anthropocene’, highlighting research about humanity’s footprint on Earth.

The difficulty is that the concept has taken off while geologists have been locked in discussion about how the Anthropocene should be measured, and when it started. One concern is that a rejection of the proposed epoch could lead to the perception that scientists somehow doubt that there is a human fingerprint on global change.

The Anthropocene concept, in its wider sense, is more than one century old1. The word was used at least as long ago as 1922 by Russian geologist Aleksei Pavlov. The term was popularized after Dutch atmospheric chemist Paul Crutzen and US biologist Eugene Stoermer reintroduced it in 2000. At the time, Crutzen and Stoermer were less concerned with finding a precise start date than researchers are now, but they did have a preference2: “To assign a more specific date to the onset of the ‘anthropocene’ seems somewhat arbitrary, but we propose the latter part of the 18th century, although we are aware that alternative proposals can be made (some may even want to include the entire holocene).” In 2002, Crutzen wrote in Nature3: “It seems appropriate to assign the term ‘Anthropocene’ to the present, in many ways human-dominated, geological epoch, supplementing the Holocene. [It] could be said to have started in the latter part of the eighteenth century, when analyses of air trapped in polar ice showed the beginning of growing global concentrations of carbon dioxide and methane.”

But words such as ‘epoch’ and ‘period’ have precise meanings in the study of Earth’s history, which is where the ICS, as a standards-setting body, comes in. According to conventions in geology, a new geological unit of time such as the Anthropocene needs permanent signals in rocks, sediment or glaciers. Candidates for such signals include microplastics, particulates from burnt fossil fuels, pesticide residues or radioactive isotopes from nuclear-bomb tests. The proposed marker location is Crawford Lake near Toronto, Canada, where plutonium from hydrogen-bomb tests, detected in 1952, settled in the lake’s sediment. As the latest vote demonstrates, there’s some way to go before this issue is resolved.

The current lack of agreement on a start date and which marker to use should not detract from the Anthropocene as a concept. The Sustainable Development Goals (SDGs) provide a useful comparison. The principle of a set of global goals and associated targets to end poverty and achieve environmental sustainability was agreed on by the international community in 2015. But the task of defining the goals, targets and indicators came later and was left to specialists, with policymakers pledging to stay out of the process.

The measurement of progress towards each of the 17 SDGs is the responsibility of a set of ‘custodian’ agencies. These are relevant international expert bodies, working with United Nations agencies. The custodians are charged with proposing measures for the goals and targets in their area of expertise. Periodically, the agencies come together to compare notes — for example, on targets for which data could be improved — and exchange ideas before returning to their individual groups to refine their knowledge. Working in this way, involving specialists from a variety of fields, undoubtedly helps to improve knowledge.

That process is still continuing. Even now, some nine years later, around one-third of the 231 unique data indicators for SDG targets are recorded in the second-highest category of accuracy. Whether countries are able to regularly produce data, a requirement of the highest tier, does not negate the necessity of achieving the goals. The same overarching principle could be applied to the Anthropocene. The absence of an agreed marker and a specific start date should not detract from the reality of a discernible human fingerprint on Earth systems.

Measurement matters. It is needed not least so that the world is confident that the Anthropocene’s start date and marker are grounded in the broadest consensus of scholarly knowledge. Geologists must quickly resolve their disagreements. At the same time, there is little doubt that the world is in an Anthropocene, as understood by researchers who use the term, and that course correction is needed.

[ad_2]

Source Article Link

Categories
Life Style

Geologists reject the Anthropocene as Earth’s new epoch — after 15 years of debate

[ad_1]

After 15 years of discussion and exploration, a committee of researchers has decided that the Anthropocene — generally understood to be the age of irreversible human impacts on the planet — will not become an official epoch in Earth’s geological timeline. The ruling, first reported by The New York Times, is meant to be final, but is being challenged by two leading members of the committee that ran the vote.

Twelve members of the international Subcommission on Quaternary Stratigraphy (SQS) voted against the proposal to create an Anthropocene epoch, and only four voted for it. That would normally constitute an unqualified defeat, but a dramatic challenge has arisen from the chair of the SQS, palaeontologist Jan Zalasiewicz at the University of Leicester, UK, and one of the group’s vice-chairs, stratigrapher Martin Head at Brock University in St Catharines, Canada.

In a 6 March press statement, they said that they are asking for the vote to be annulled. They added that “the alleged voting has been performed in contravention of the statutes of the International Commission on Stratigraphy” (ICS), including statutes governing the eligibility to vote. Zalasiewicz told Nature that he couldn’t comment further just yet, but that neither he nor Head had “instigated the vote or agreed to it, so we are not responsible for procedural irregularities”.

The SQS is a subcommittee of the ICS. Normally, there would be no appeals process for a losing vote. ICS chair David Harper, a palaeontologist at Durham University, UK, had confirmed to Nature before the 6 March press statement that the proposal “cannot be progressed further”. Proponents could put forward a similar idea in the future.

If successful, the proposal would have codified the end of the current Holocene epoch, which has been going on since the end of the last ice age 11,700 years ago, and set the start of the Anthropocene in the year 1952. This is when plutonium from hydrogen-bomb tests showed up in the sediment of Crawford Lake near Toronto, Canada, a site chosen by some geologists to be designated as a ‘golden spike’ as capturing a pristine record of humans’ impact on Earth. Other signs of human influence in the geological record include microplastics, pesticides and ash from fossil-fuel combustion.

But pending the resolution of the challenge, the lake and its plutonium residue won’t get a golden spike. Selecting one site as such a marker “always felt a bit doomed, because human impacts on the planet are global”, says Zoe Todd, an anthropologist at Simon Fraser University in Burnaby, Canada. “This is actually an invitation for us to completely rethink how we define what the world is experiencing.”

A cultural concept

Although the Anthropocene probably will not be added to the geological timescale, it remains a broad cultural concept already used by many to describe the era of accelerating human impacts, such as climate change and biodiversity loss. “We are now on a fundamentally unpredictable planet in ways that we have not experienced for the last 12,000 years,” says Julia Adeney Thomas, a historian at the University of Notre Dame, in Indiana. “That understanding of the Anthropocene is crystal clear.”

The decision to reject the designation was made public through The New York Times on 5 March, after the SQS had concluded its month-long voting process, but before committee leaders had finalized discussions and made an official announcement. Philip Gibbard, a geologist at the University of Cambridge, UK, who is on the SQS, says that the crux of the annulment challenge is that Zalasiewicz and Head objected to the voting process kicking off on 1 February. The rest of the committee wanted to move forward with a vote and did so according to SQS rules, Gibbard says. “There’s a lot of sour grapes going on here,” he adds.

Had the proposal made it through the SQS, it would have needed to clear two more hurdles: first, a ratification vote by the full stratigraphic commission, and then a final one in August at a forum of the International Union of Geological Sciences.

Frustrated by defeat

Some of those who helped to draw up the proposal, through an Anthropocene working group commissioned by the SQS, are frustrated by the apparent defeat. They had spent years studying a number of sites around the world that could represent the start of a human-influenced epoch. They performed fresh environmental analyses on many of the sites, including studying nuclear debris, fossil-fuel ash and other markers of humans’ impact in geological layers, before settling on Crawford Lake.

“We have made it very clear that the planet we’re living on is different than it used to be, and that the big tipping point was in the mid-twentieth century,” says Francine McCarthy, a micropalaeontologist at Brock University who led the Crawford Lake proposal1. Even though the SQS has rejected it, she says she will keep working to highlight the lake’s exceptionally preserved record of human activities. “Crawford Lake is just as great a place as it ever was.”

“To be honest, I am very disappointed with the SQS outcome,” says working-group member Yongming Han, a geochemist at the Institute of Earth Environment of the Chinese Academy of Sciences in Xi’an. “We all know that the planet has entered a period in which humans act as a key force and have left indisputable stratigraphic evidences.”

For now, the SQS and the ICS will sort out how to handle Zalasiewicz and Head’s request for a vote annulment. Meanwhile, scientific and public discussions about how best to describe the Anthropocene continue.

One emerging argument is that the Anthropocene should be defined as an event in geological history — similar to the rise of atmospheric oxygen just over two billion years ago, known as the Great Oxidation Event — but not as a formal epoch2. This would make more sense because geological events unfold as transformations over time, such as humans industrializing and polluting the planet, rather than as an abrupt shift from one state to another, says Erle Ellis, an ecologist at the University of Maryland Baltimore County in Baltimore. “We need to think about this as a broader process, not as a distinct break in time,” says Ellis, who resigned from the Anthropocene working group last year because he felt it was looking at the question too narrowly.

This line of thinking played a part in at least some of the votes to reject the idea of an Anthropocene epoch. Two SQS members told Nature they had voted down the proposal in part because of the long and evolving history of human impacts on Earth.

“By voting ‘no’, they [the SQS] actually have made a stronger statement,” Ellis says: “that it’s more useful to consider a broader view — a deeper view of the Anthropocene.”

[ad_2]

Source Article Link