Thursday, July 29, 2021

3537. A Green Critique of the Global Alliance for a Green New Deal

 By Sandy Irvine,  Sandy Irvine's Green Blog, July 20, 2021

This paper argues that we might be wise to hold the applause for the Global Alliance for a Green New Deal (GAGND). It seems to be another case of ‘cakeism’, the belief that we can have our cake and eat it: a long list of In reality, the available material on the GAGND suggests a severe case of pie-in-the sky thinking. Indeed, it offers comfort food for those reluctant and even unwilling to face the breadth and depth of the challenges we face.Indeed, it offers comfort food for those reluctant and even unwilling to face the breadth and depth of the challenges we face. (

There are, of course, many definitions of a ‘Green New Deal’ and associated policies (eg ). All seem to be variants of some kind of turquoise Keynesianism, replete with woefully exaggerated hopes regarding what can be sustainably delivered by renewable energy, battery storage technology, efficiency gains and recycling. Some are based on pure mythology, not least the thermodynamically impossible 100% “circular economy”. Indeed, there seems to be a hidden assumption of the possibility for radical ‘dematerialisation’ and ‘absolute decoupling’ for which there is simply no evidence. It also appears that there is a conflation with electricity supply with total energy consumption, thereby skirting real barriers in fields such as agriculture and transportation (cf )

It might be remembered that the original New Deal did not deal with the problems it claimed to address. The then unemployment crisis in the USA persisted at a high level until the rearmament programme kicked in. It also inflicted severe ecological damage (dams etc) alongside, to be fair, some beneficial programmes of soil conservation and tree planting. Today, President Joe Biden’s New Deal is essentially an infrastructure construction package, one that will do immense ecological damage, both in terms of further encroachment on wildlife habitat and farmland as well as all the concrete and steel it will devour
(see: and

It might also be remembered that Biden’s action on, say, pipeline construction has largely been in the form of temporary halts, not radical change of direction. Indeed the ‘Financial Times’ deemed his plans to be a “boost” to the fossil fuel industry. They also include the false fix of carbon capture and storage (cf

Similarly, the underpinning analysis on the GAGND website reduces the total crisis to one largely of excess carbon emissions (cf ). It largely ignores other GHGs, not least methane. In reality, global overheating is only one of many symptoms of ‘overshoot’. There are so many more: plastification (with current plans for massive expansion of plastic production), a lethal cocktail of air and water pollution, widespread and worsening toxic contamination, oceanic dead zones, soil denutrification and erosion, spreading crop and forest monocultures, aquifer depletion, massive overfishing, destruction of ocean beds, paving over of land by suburban sprawl and other construction ……

The website does talk of a “climate and nature crisis” but there is little sense of an appropriate ‘new deal’ for the rest of nature. The drastic decline in the richness and variety of non-human nature scarcely gets the prominence it deserves. Furthermore, the explicit linkage of “climate and nature” suggests that that global overheating and biodiversity meltdown go hand in hand. In reality there are far bigger drivers of extinction and endangerment (see diagram below), ones intimately linked to human numbers, not least the number of mouths to feed and people to house.{see: and )

3536. A Soil-Science Revolution Upends Plans to Fight Climate Change

By Gabriel Popkin, Quanta Magazine, July 27, 2021

The hope was that the soil might save us. With civilization continuing to pump ever-increasing amounts of carbon dioxide into the atmosphere, perhaps plants — nature’s carbon scrubbers — might be able to package up some of that excess carbon and bury it underground for centuries or longer.

That hope has fueled increasingly ambitious climate change–mitigation plans. Researchers at the Salk Institute, for example, hope to bioengineer plants whose roots will churn out huge amounts of a carbon-rich, cork-like substance called suberin. Even after the plant dies, the thinking goes, the carbon in the suberin should stay buried for centuries. This Harnessing Plants Initiative is perhaps the brightest star in a crowded firmament of climate change solutions based on the brown stuff beneath our feet.

Such plans depend critically on the existence of large, stable, carbon-rich molecules that can last hundreds or thousands of years underground. Such molecules, collectively called humus, have long been a keystone of soil science; major agricultural practices and sophisticated climate models are built on them.

But over the past 10 years or so, soil science has undergone a quiet revolution, akin to what would happen if, in physics, relativity or quantum mechanics were overthrown. Except in this case, almost nobody has heard about it — including many who hope soils can rescue the climate. “There are a lot of people who are interested in sequestration who haven’t caught up yet,” said Margaret Torn, a soil scientist at Lawrence Berkeley National Laboratory.

A new generation of soil studies powered by modern microscopes and imaging technologies has revealed that whatever humus is, it is not the long-lasting substance scientists believed it to be. Soil researchers have concluded that even the largest, most complex molecules can be quickly devoured by soil’s abundant and voracious microbes. The magic molecule you can just stick in the soil and expect to stay there may not exist.

“I have The Nature and Properties of Soils in front of me — the standard textbook,” said Gregg Sanford, a soil researcher at the University of Wisconsin, Madison. “The theory of soil organic carbon accumulation that’s in that textbook has been proven mostly false … and we’re still teaching it.”

The consequences go far beyond carbon sequestration strategies. Major climate models such as those produced by the Intergovernmental Panel on Climate Change are based on this outdated understanding of soil. Several recent studies indicate that those models are underestimating the total amount of carbon that will be released from soil in a warming climate. In addition, computer models that predict the greenhouse gas impacts of farming practices — predictions that are being used in carbon markets — are probably overly optimistic about soil’s ability to trap and hold on to carbon.

It may still be possible to store carbon underground long term.  Indeed, radioactive dating measurements suggest that some amount of carbon can stay in the soil for centuries. But until soil scientists build a new paradigm to replace the old — a process now underway — no one will fully understand why. 

The Death of Humus

Soil doesn’t give up its secrets easily. Its constituents are tiny, varied and outrageously numerous. At a bare minimum, it consists of minerals, decaying organic matter, air, water, and enormously complex ecosystems of microorganisms. One teaspoon of healthy soil contains more bacteria, fungi and other microbes than there are humans on Earth.

The German biologist Franz Karl Achard was an early pioneer in making sense of the chaos. In a seminal 1786 study, he used alkalis to extract molecules made of long carbon chains from peat soils. Over the centuries, scientists came to believe that such long chains, collectively called humus, constituted a large pool of soil carbon that resists decomposition and pretty much just sits there. A smaller fraction consisting of shorter molecules was thought to feed microbes, which respired carbon dioxide to the atmosphere.

This view was occasionally challenged, but by the mid-20th century, the humus paradigm was “the only game in town,” said Johannes Lehmann, a soil scientist at Cornell University. Farmers were instructed to adopt practices that were supposed to build humus. Indeed, the existence of humus is probably one of the few soil science facts that many non-scientists could recite.

What helped break humus’s hold on soil science was physics. In the second half of the 20th century, powerful new microscopes and techniques such as nuclear magnetic resonance and X-ray spectroscopy allowed soil scientists for the first time to peer directly into soil and see what was there, rather than pull things out and then look at them.

What they found — or, more specifically, what they didn’t find — was shocking: there were few or no long “recalcitrant” carbon molecules — the kind that don’t break down. Almost everything seemed to be small and, in principle, digestible.

“We don’t see any molecules in soil that are so recalcitrant that they can’t be broken down,” said Jennifer Pett-Ridge, a soil scientist at Lawrence Livermore National Laboratory. “Microbes will learn to break anything down — even really nasty chemicals.”

Lehmann, whose studies using advanced microscopy and spectroscopy were among the first to reveal the absence of humus, has become the concept’s debunker-in-chief. A 2015 Nature paper he co-authored states that “the available evidence does not support the formation of large-molecular-size and persistent ‘humic substances’ in soils.” In 2019, he gave a talk with a slide containing a mock death announcement for “our friend, the concept of Humus.”

Over the past decade or so, most soil scientists have come to accept this view. Yes, soil is enormously varied. And it contains a lot of carbon. But there’s no carbon in soil that can’t, in principle, be broken down by microorganisms and released into the atmosphere. The latest edition of The Nature and Properties of Soils, published in 2016, cites Lehmann’s 2015 paper and acknowledges that “our understanding of the nature and genesis of soil humus has advanced greatly since the turn of the century, requiring that some long-accepted concepts be revised or abandoned.”

Old ideas, however, can be very recalcitrant. Few outside the field of soil science have heard of humus’s demise.

Buried Promises

At the same time that soil scientists were rediscovering what exactly soil is, climate researchers were revealing that increasing amounts of carbon dioxide in the atmosphere were rapidly warming the climate, with potentially catastrophic consequences.

Thoughts soon turned to using soil as a giant carbon sink. Soils contain enormous amounts of carbon — more carbon than in Earth’s atmosphere and all its vegetation combined. And while certain practices such as plowing can stir up that carbon — farming, over human history, has released an estimated 133 billion metric tons of carbon into the atmosphere — soils can also take up carbon, as plants die and their roots decompose.

Scientists began to suggest that we might be able to coax large volumes of atmospheric carbon back into the soil to dampen or even reverse the damage of climate change.

In practice, this has proved difficult. An early idea to increase carbon stores — planting crops without tilling the soil — has mostly fallen flat. When farmers skipped the tilling and instead drilled seeds into the ground, carbon stores grew in upper soil layers, but they disappeared from lower layers. Most experts now believe that the practice redistributes carbon within the soil rather than increases it, though it can improve other factors such as water quality and soil health.

Efforts like the Harnessing Plants Initiative represent something like soil carbon sequestration 2.0: a more direct intervention to essentially jam a bunch of carbon into the ground.

The initiative emerged when a team of scientists at the Salk Institute came up with an idea: Create plants whose roots produce an excess of carbon-rich molecules. By their calculations, if grown widely, such plants might sequester up to 20% of the excess carbon dioxide that humans add to the atmosphere every year.

The Salk scientists zeroed in on a complex, cork-like molecule called suberin, which is produced by many plant roots. Studies from the 1990s and 2000s had hinted that suberin and similar molecules could resist decomposition in soil.

With flashy marketing, the Harnessing Plants Initiative gained attention. An initial round of fundraising in 2019 brought in over $35 million. Last year, the multibillionaire Jeff Bezos contributed $30 million from his “Earth Fund.”

But as the project gained momentum, it attracted doubters. One group of researchers noted in 2016 that no one had actually observed the suberin decomposition process. When those authors did the relevant experiment, they found that much of the suberin decayed quickly.

In 2019, Joanne Chory, a plant geneticist and one of the Harnessing Plant Initiative’s project leaders, described the project at a TED conference. Asmeret Asefaw Berhe, a soil scientist at the University of California, Merced, who spoke at the same conference, pointed out to Chory that according to modern soil science, suberin, like any carbon-containing compound, should break down in soil. (Berhe, who has been nominated to lead the U.S. Department of Energy’s Office of Science, declined an interview request.)

Around the same time, Hanna Poffenbarger, a soil researcher at the University of Kentucky, made a similar comment after hearing Wolfgang Busch, the other project leader, speak at a workshop. “You should really get some soil scientists on board, because the assumption that we can breed for more recalcitrant roots — that may not be valid,” Poffenbarger recalls telling Busch.

Questions about the project surfaced publicly earlier this year, when Jonathan Sanderman, a soil scientist at the Woodwell Climate Research Center in Woods Hole, Massachusetts, tweeted, “I thought the soil biogeochem community had moved on from the idea that there is a magical recalcitrant plant compound. Am I missing some important new literature on suberin?” Another soil scientist responded, “Nope, the literature suggests that suberin will be broken down just like every other organic plant component. I’ve never understood why the @salkinstitute has based their Harnessing Plant Initiative on this premise.”

Busch, in an interview, acknowledged that “there is no unbreakable biomolecule.” But, citing published papers on suberin’s resistance to decomposition, he said, “We are still very optimistic when it comes to suberin.”

He also noted a second initiative Salk researchers are pursuing in parallel to enhancing suberin. They are trying to design plants with longer roots that could deposit carbon deeper in soil. Independent experts such as Sanderman agree that carbon tends to stick around longer in deeper soil layers, putting that solution on potentially firmer conceptual ground.

Chory and Busch have also launched collaborations with Berhe and Poffenbarger, respectively. Poffenbarger, for example, will analyze how soil samples containing suberin-rich plant roots change under different environmental conditions. But even those studies won’t answer questions about how long suberin sticks around, Poffenbarger said — important if the goal is to keep carbon out of the atmosphere long enough to make a dent in global warming.

Beyond the Salk project, momentum and money are flowing toward other climate projects that would rely on long-term carbon sequestration and storage in soils. In an April speech to Congress, for example, President Biden suggested paying farmers to plant cover crops, which are grown not for harvest but to nurture the soil in between plantings of cash crops. Evidence suggests that when cover crop roots break down, some of their carbon stays in the soil — although as with suberin, how long it lasts is an open question.

Not Enough Bugs in the Code

Recalcitrant carbon may also be warping climate prediction.

In the 1960s, scientists began writing large, complex computer programs to predict the global climate’s future. Because soil both takes up and releases carbon dioxide, climate models attempted to take into account soil’s interactions with the atmosphere. But the global climate is fantastically complex, and to enable the programs to run on the machines of the time, simplifications were necessary. For soil, scientists made a big one: They ignored microbes in the soil entirely. Instead, they basically divided soil carbon into short-term and long-term pools, in accordance with the humus paradigm.

More recent generations of models, including ones that the Intergovernmental Panel on Climate Change uses for its widely read reports, are essentially palimpsests built on earlier ones, said Torn. They still assume soil carbon exists in long-term and short-term pools. As a consequence, these models may be overestimating how much carbon will stick around in soils and underestimating how much carbon dioxide they will emit.

Last summer, a study published in Nature examined how much carbon dioxide was released when researchers artificially warmed the soil in a Panamanian rainforest to mimic the long-term effects of climate change. They found that the warmed soil released 55% more carbon than nearby unwarmed areas — a much larger release than predicted by most climate models. The researchers think that microbes in the soil grow more active at the warmer temperatures, leading to the increase.

The study was especially disheartening because most of the world’s soil carbon is in the tropics and the northern boreal zone. Despite this, leading soil models are calibrated to results of soil studies in temperate countries such as the U.S. and Europe, where most studies have historically been done. “We’re doing pretty bad in high latitudes and the tropics,” said Lehmann.

Even temperate climate models need improvement. Torn and colleagues reported earlier this year that, contrary to predictions, deep soil layers in a California forest released roughly a third of their carbon when warmed for five years.

Ultimately, Torn said, models need to represent soil as something closer to what it actually is: a complex, three-dimensional environment governed by a hyper-diverse community of carbon-gobbling bacteria, fungi and other microscopic beings. But even smaller steps would be welcome. Just adding microbes as a single class would be major progress for most models, she said.

Fertile Ground

If the humus paradigm is coming to an end, the question becomes: What will replace it?

One important and long-overlooked factor appears to be the three-dimensional structure of the soil environment. Scientists describe soil as a world unto itself, with the equivalent of continents, oceans and mountain ranges. This complex microgeography determines where microbes such as bacteria and fungi can go and where they can’t; what food they can gain access to and what is off limits.

A soil bacterium “may be only 10 microns away from a big chunk of organic matter that I’m sure they would love to degrade, but it’s on the other side of a cluster of minerals,” said Pett-Ridge. “It’s literally as if it’s on the other side of the planet.”

Another related, and poorly understood, ingredient in a new soil paradigm is the fate of carbon within the soil. Researchers now believe that almost all organic material that enters soil will get digested by microbes. “Now it’s really clear that soil organic matter is just this loose assemblage of plant matter in varying degrees of degradation,” said Sanderman. Some will then be respired into the atmosphere as carbon dioxide. What remains could be eaten by another microbe — and a third, and so on. Or it could bind to a bit of clay or get trapped inside a soil aggregate: a porous clump of particles that, from a microbe’s point of view, could be as large as a city and as impenetrable as a fortress. Studies of carbon isotopes have shown that a lot of carbon can stick around in soil for centuries or even longer. If humus isn’t doing the stabilizing, perhaps minerals and aggregates are.

Before soil science settles on a new theory, there will doubtless be more surprises. One may have been delivered recently by a group of researchers at Princeton University who constructed a simplified artificial soil using microfluidic devices — essentially, tiny plastic channels for moving around bits of fluid and cells. The researchers found that carbon they put inside an aggregate made of bits of clay was protected from bacteria. But when they added a digestive enzyme, the carbon was freed from the aggregate and quickly gobbled up. “To our surprise, no one had drawn this connection between enzymes, bacteria and trapped carbon,” said Howard Stone, an engineer who led the study.

Lehmann is pushing to replace the old dichotomy of stable and unstable carbon with a “soil continuum model” of carbon in progressive stages of decomposition. But this model and others like it are far from complete, and at this point, more conceptual than mathematically predictive.

Researchers agree that soil science is in the midst of a classic paradigm shift. What nobody knows is exactly where the field will land — what will be written in the next edition of the textbook. “We’re going through a conceptual revolution,” said Mark Bradford, a soil scientist at Yale University. “We haven’t really got a new cathedral yet. We have a whole bunch of churches that have popped up.”

Tuesday, July 27, 2021

3535. This ‘Shazam’ for Birds Could Help Save Them

By Margaret Renkl, The New York Times, July 26, 2021 

Northern Cardinal

I spent my entire childhood playing in the woods and meadows of rural Alabama. The world back then was lush and green: cooled by creeks, carpeted by pine needles, attended by birdsong. In those days there were nearly three billion more birds in North America than there are today, and my young days played out beneath the sound of their music.

The staggering loss of birds — nearly a third of them since 1970 — is due to human behavior: to climate change, to deforestation and ecosystem fragmentation, to insecticides and free-roaming pets, to light pollution in our skies and microplastics in our waterways, to glass-encased skyscrapers protruding into migratory flyways, among other choices that favor our own convenience over the lives of our wild neighbors.

I can’t help but wonder how much of the blame lies, too, in indifference, our failure even to notice what we’ve lost. Birds can be secretive creatures, staying high in the treetops or deep in the underbrush. Even those in plain sight often move startlingly quickly, appearing as hardly more than a flash of color, a blur of wings. Except for the background sound of birdsong, many people are never aware of how many birds — or how few — they share the world with.

Apps like iNaturalist from National Geographic and the California Academy of Sciences help to close that gap, functioning as both electronic field guides and vast data-collection devices. They learn as we learn, improving with every photo and map pin we upload, helping experts understand a planet undergoing profound change. But what of the vast number of birds we never see, those we only hear? To offer that feature — one that accurately and consistently recognizes birds by sound alone — would be the birding equivalent of finding the Holy Grail.

Identifying birds by their songs has always been difficult, for computers and humans alike. Every species of bird has a range of vocalizations, sometimes an immense range, and those vocalizations can have regional inflections, just as people speak with local accents. In some species, individual birds put a unique spin on their songs, too. A mockingbird is the avian equivalent of a jazz musician.

Last month, the Cornell Lab of Ornithology released an updated version of its Merlin Bird ID app, which allows users to identify birds by song. There are other voice-recognition apps for birds, but they are accurate barely 50 percent of the time. Though Merlin doesn’t claim to be 100 percent accurate, it comes very close. Drawing on a database of notes and recordings contributed by tens of thousands of citizen scientists through the Lab’s eBird initiative, Merlin listens as you listen, in real time, and tells you what you’re hearing. The app can identify some 400 North American species so far and will keep expanding. It’s an immense achievement, a quantum leap forward, nothing less than “a Shazam for bird songs,” as an article in Fast Company put it. 

Naturally, I had to try out the new technology. I am far from an expert birder, but I do know my avian neighbors, and I figured a good way to test Merlin’s accuracy was to try it with birds I can already recognize by ear.

The first test didn’t bode well. I was reading on the sofa when I heard a Carolina wren singing just above my head. It was hopping around in a hanging basket barely a foot beyond the glass and singing its head off. That wren was as close as any bird was ever going to get, but the app was stumped. “Merlin has no matches,” it reported. Merlin fared no better in the two other recordings I made indoors.

But outside, something magical happened. I set my phone down on the table on my back deck, opened the Merlin app, chose “Sound ID” and hit the microphone button. Immediately a spectrogram of sound waves began to scroll across the screen. Every time a bird sings, the sound registers as a kind of picture of the song. By comparing that picture with others in its database, the app arrives at an ID.

I watched as Merlin rolled out the names of bird after bird — tufted titmouseEuropean starlingCarolina chickadeenorthern cardinalAmerican crowwhite-breasted nuthatcheastern towheehouse wrenAmerican goldfinchblue jayeastern bluebirdAmerican robinCarolina wrenhouse finch. It didn’t miss a single one.

What amazed me was not merely the accuracy of the ID but also the way the app untangled the layers of song, correctly identifying the birds that were singing in my yard, as well the birds that were singing next door and the birds that were singing across the street. If the same bird sang a second time, the app highlighted the name it had already listed. Watching those highlights play across the growing list of birds was almost like watching fingers fly across a piano keyboard.

Then I started seeing the names of birds I’d never seen in this yard before, birds that for me have existed only as undifferentiated sounds in the trees: Kentucky warbler, blue-gray gnatcatcher, yellow-breasted chat. The new bird I’d been hearing but not seeing all summer long, the one whose song sounded to me like, “Here, here, do you know my name?” turned out to be a magnificent summer tanager. Merlin also picked up the song of a yellow-throated warbler, a bird the app identified as uncommon for this area. I knew two were here because one of their babies fell out of a nest onto my son’s car — it was safely reared by the wildlife experts at Walden’s Puddle and released back into the wild — but I had never heard them sing. At least, I didn’t know what I was hearing when I heard them sing.

This enchanting app is aptly named. Watching those birds appear on my phone screen in response to the sound of their voices in the air was a kind of wizardry — like watching the notes of a song become visible, like having fairies or angels suddenly embodied before me. Merlin made me see what before I could only imagine.

The timing for this app is perfect. During the pandemic quarantines, many people took up bird-watching as a pastime, and people who notice birds almost invariably become people who love birds. Love can’t save the environment, of course, but when enough voters fall in love, they can surely shift the political winds toward preservation.

That’s because we are a species motivated by love. Our most powerful work is done in the fervor of love; our most urgent effort is born from the fear of losing what we love best. To save birds, we need to make the whole human race fall in love with birds. What if all the people with phones in their pockets could suddenly hear beyond the sounds of their own machines? What if we could all discover how surrounded we are by bright-winged fairies and golden-voiced angels come down to live among us?

Thanks to the Cornell Lab of Ornithology, now we can.