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Permafrost: a ticking carbon time bomb
Permafrost: a ticking carbon time bomb
Sheltered by snow-spattered mountains, the Stordalen mire is a flat, marshy plateau, pockmarked with muddy puddles. A whiff of rotten eggs wafts through the fresh air.
Here in the Arctic in Sweden’s far north, about 10 kilometres (six miles) east of the tiny town of Abisko, global warming is happening three times faster than in the rest of the world.
On the peatland, covered in tufts of grass and shrubs dotted with blue and orange berries and little white flowers, looms a moonlander-like pod hinting at this far-flung site’s scientific significance.
Researchers are studying the frozen—now shapeshifting—earth below known as permafrost.
As Keith Larson walks between the experiments, the boardwalks purposefully set out in a grid across the peat sink into the puddles and ponds underneath and tiny bubbles appear.
The distinct odour it emits is from hydrogen sulfide, sometimes known as swamp gas. But what has scientists worried is another gas rising up with it: methane.
Carbon stores, long locked in the permafrost, are now seeping out.
Between carbon dioxide (CO2) and methane, permafrost contains some 1,700 billion tonnes of organic carbon, almost twice the amount of carbon already present in the atmosphere.
Methane lingers in the atmosphere for only 12 years compared to centuries for CO2 but is about 25 times more potent as a greenhouse gas over a 100-year period.
Thawing permafrost is a carbon “time bomb”, scientists have warned.
Vicious circle
In the 1970s, “when researchers first started showing up and investigating these habitats, these ponds didn’t exist”, says Larson, project coordinator for the Climate Impacts Research Centre at Umea University, based at the Abisko Scientific Research Station.
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Net zero policies are ’emperor’s new clothes,’ academics warn
Net zero policies are ’emperor’s new clothes,’ academics warn
Net zero targets are a “fantasy” that often just protect “business as usual,” a leading expert in environment and sustainability has said.
Dr. James Dyke, Assistant Director of the Global Systems Institute at the University of Exeter, criticized net zero targets as a “great idea in principle” but which “help perpetuate a belief in technological salvation and diminish the sense of urgency surrounding the need to curb emissions now.”
The excoriating critique is published in “Negotiating Climate Change in Crisis,” a new essay volume on the climate crisis featuring prominent social scientists and humanities scholars from around the world, co-edited by the University of Exeter Business School’s Professor Steffen Boehm.
In a chapter titled “Why net zero policies do more harm than good,” Dr. Dyke and his co-authors Dr. Wolfgang Knorr and Professor Sir Robert Watson argue that the discourse around net zero hinges on deploying potentially dangerous ‘fairytale’ technologies such as carbon capture.
Their essay looks at how projecting a future with more trees was first used by the US to “in effect offset the burning of coal, oil and gas now.”
They go on to argue that the Paris Agreement’s 1.5 degree Celsius emissions target allowed “untested carbon dioxide removal mechanisms” to be included in climate-economic modeling.
They describe Bioenergy Carbon Capture and Storage (BECCS) as a “savior technology,” saying “the mere prospect of carbon capture and storage gave policy makers a way out of making the much-needed immediate cuts to greenhouse gas emissions.”
The authors say: “It has been estimated that BECCS could demand an area of land approaching twice the size of India. How will that be achieved at the same time as feeding eight to 10 billion people around the middle of the century, or without destroying native vegetation and biodiversity?
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A third of global farmland at ‘high’ pesticide pollution risk
A third of global farmland at ‘high’ pesticide pollution risk
A third of the planet’s agricultural land is at “high risk” of pesticide pollution from the lingering residue of chemical ingredients that can leach into water supplies and threaten biodiversity, according to research published Monday.
The use of pesticides has soared globally as agricultural production has expanded, prompting growing fears over environmental damage and calls to cut hazardous chemical use.
Researchers in Australia modelled pollution risk across 168 countries with data on the usage of 92 active pesticide ingredients and found “widespread global pesticide pollution risk”.
They highlighted several acutely vulnerable ecosystems in South Africa, China, India, Australia and Argentina, at the nexus of high pollution risk, high water scarcity and high biodiversity.
The study, published in Nature Geoscience, found that overall 64 percent of global agricultural land —approximately 24.5 million square kilometres (9.4 million sq miles)—was at risk of pesticide pollution from more than one active ingredient, and 31 percent is at high risk.
“It is significant because the potential pollution is widespread and some regions at risk also bear high biodiversity and suffer from water scarcity,” said lead author Fiona Tang, of the University of Sydney’s School of Civil Engineering.
Tang said there were a number of factors that would contribute to a region becoming a potential contamination hotspot, including using excessive amounts of pesticides or those containing highly toxic substances.
Some environmental factors may also slow the breakdown of the pesticides into non-toxic substances, like cold temperatures or low soil carbon, while heavy rainfall might also cause high levels of run-off.
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Kelly MacNamara, phys.org, pesticides, agriculture, industrial agriculture, modern agriculture, food production, food, pollution
Methane emissions from abandoned oil and gas wells underestimated
Methane emissions from abandoned oil and gas wells underestimated
A recent McGill study published in Environmental Science and Technology finds that annual methane emissions from abandoned oil and gas (AOG) wells in Canada and the US have been greatly underestimated—by as much as 150% in Canada, and by 20% in the US. Indeed, the research suggests that methane gas emissions from AOG wells are currently the 10th and 11th largest sources of anthropogenic methane emission in the US and Canada, respectively. Since methane gas is a more important contributor to global warming than carbon dioxide, especially over the short term, the researchers believe that it is essential to gain a clearer understanding of methane emissions from AOG wells to understand their broader environmental impacts and move towards mitigating the problem.
Multiple sources of uncertainty
The researchers show that the difficulties in estimating overall methane emissions from AOG wells in both countries are due to a lack of information about both the quantities of methane gas being emitted annually from AOG wells (depending on whether and how well they have been capped), and about the number of AOG wells themselves.
“Oil and gas development started in the late 1850s both in Canada and the US,” explains Mary Kang, the senior author on the paper and an assistant professor in the Department of Civil Engineering at McGill. “Many companies that dug wells have come and gone since then, so it can be hard to find records of the wells that once existed.”
Thousands of undocumented AOG wells
To determine the number of AOG wells, the researchers analyzed information from 47 state, provincial or territorial databases as well as from research articles and national repositories of drilled and active wells in the US and Canada.
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It’s time environmentalists talked about the population problem
It’s time environmentalists talked about the population problem
In all the talk of tackling environmental problems such as climate change, the problem of population growth often escapes attention. Politicians don’t like talking about it. By and large, neither do environmentalists—but former Greens leader Bob Brown has bucked that trend.
Brown recently declared the world’s population must start to decline before 2100, telling The Australian newspaper: “We are already using more than what the planet can supply and we use more than the living fabric of the planet in supply. That’s why we wake up every day to fewer fisheries, less forests, more extinctions and so on. The human herd at eight billion is the greatest herd of mammals ever on this planet and it is unsustainable to have that growing.”
Research suggests our species has far exceeded its fair share of the planetary bounty, and Brown is right to call for the global population to peak. It is high time others joined the chorus—not only other environmentalists, but those concerned with international development and human rights.
Population growth, by the numbers
COVID-19 has killed more than one million people. While undeniably tragic, the figure is minor compared to world’s annual growth in population, estimated by the United Nations at about 83 million.
In 1900, the world’s population was about 1.6 billion people. By 2023 it’s expected to hit 8 billion. According to the UN, it will reach 9.7 billion by 2050 and 11.2 billion by 2100.
(The US-based Institute for Health Metrics and Evaluation recently forecast a lower peak of about 9.7 billion by 2064, falling to about 8.8 billion by 2100.)
Why is the population growing so fast? Much of it is due to advanced fertilizers and intensive farming practices, leading to higher crop yields that can sustain more people. Health care has improved, and people are living much longer. And many parts of the world have historically had high fertility rates.
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History shows that societies collapse when leaders undermine social contracts
History shows that societies collapse when leaders undermine social contracts
All good things must come to an end. Whether societies are ruled by ruthless dictators or more well-meaning representatives, they fall apart in time, with different degrees of severity. In a new paper, anthropologists examined a broad, global sample of 30 pre-modern societies. They found that when “good” governments—ones that provided goods and services for their people and did not starkly concentrate wealth and power—fell apart, they broke down more intensely than collapsing despotic regimes. And the researchers found a common thread in the collapse of good governments: leaders who undermined and broke from upholding core societal principles, morals, and ideals.
“Pre-modern states were not that different from modern ones. Some pre-modern states had good governance and weren’t that different from what we see in some democratic countries today,” says Gary Feinman, the MacArthur curator of anthropology at Chicago’s Field Museum and one of the authors of a new study in Frontiers in Political Science. “The states that had good governance, although they may have been able to sustain themselves slightly longer than autocratic-run ones, tended to collapse more thoroughly, more severely.”
“We noted the potential for failure caused by an internal factor that might have been manageable if properly anticipated,” says Richard Blanton, a professor emeritus of anthropology at Purdue University and the study’s lead author. “We refer to an inexplicable failure of the principal leadership to uphold values and norms that had long guided the actions of previous leaders, followed by a subsequent loss of citizen confidence in the leadership and government and collapse.”
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