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      In the wake of history’s deadliest mass extinction, ocean life may have flourished

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      Following the most severe known mass extinction in Earth’s history, vibrant marine ecosystems may have recovered within just a million years, researchers report in the Feb. 10 Science. That’s millions of years faster than previously thought. The evidence, which lies in a diverse trove of pristine fossils discovered near the city of Guiyang in South China, may represent the early foundations of today’s ocean-dwelling ecosystems.

      The conventional story was that the ocean was kind of dead for millions of years after this mass extinction, says paleontologist Peter Roopnarine of the California Academy of Sciences in San Francisco, who was not involved in the research. “Well, that’s not true. The ocean [was] very much alive.”

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      The Great Dying, or Permian-Triassic mass extinction, occurred around 251.9 million years ago, at the end of the Permian Period, after a series of massive volcanic eruptions (SN: 12/6/18).

      “The oceans warmed significantly, and there’s evidence for acidification, deoxygenation [causing widespread dead zones], as well as poisoning,” says Roopnarine. “There [were] a lot of toxic elements like sulfur entering into parts of the ocean.”

      Life in the seas suffered. More than 80 percent of marine species went extinct. Some researchers have even proposed that entire trophic levels — castes in an ecosystem’s food web — may have vanished.

      Figuring out how long life took to fully recover in the wake of all that loss has been challenging. In 2010, researchers studying fossils from the Luoping biota in China proposed that complex marine ecosystems fully rebounded within 10 million years. Later, other fossil finds, such as the Paris biota in the western United States and the Chaohu biota in China, led scientists to suggest that marine ecosystems reestablished themselves within just 3 million years.

      Then in 2015, a serendipitous discovery narrowed the gap again. Paleontologist Xu Dai, then an undergraduate student at the China University of Geosciences in Wuhan, was studying rocks from the early Triassic during a field trip near the city of Guiyang, when he split open a piece of black shale. Within the rock, he discovered a surprisingly well-preserved fossil of what would later be identified as a primitive lobster.

      The arthropod’s immaculate condition sparked a series of return trips. From 2015 to 2019, Dai, now at the University of Burgundy in Dijon, France, and his colleagues uncovered a bricolage of fossilized life: Predatory fish as long as baseball bats. Ammonoids in swirled shells. Eel-like conodonts. Early shrimps. Sponges. Bivalves. Fossilized poo.

      Fossilized coelacanths (one shown here), a type of bony fish, are the largest macrofossils yet found in the Guiyang biota.Dai et al/Science 2023

      And the prizes kept coming. Both under and within the Guiyang biota, Dai and his colleagues discovered beds of volcanic ash. An analysis of the amounts of uranium and lead in the ash revealed that the Guiyang biota contained fossils from roughly 250.7 to 250.8 million years ago (SN: 5/2/22). The dating was further supported by the types of fossils found and by an analysis of the different forms of carbon in the rocks.

      Finding a potpourri of life of this age suggests that marine ecosystems rebounded quickly after the Great Dying, within just 1 million years or so, Dai says.

      Alternatively, it may indicate that the extinction event failed to wipe out entire trophic levels, says paleontologist William Foster from the University of Hamburg in Germany, who was not involved in the study. “You have this really environmentally stressful world, but some former marine ecosystems survive.”

      Regardless, it seems clear that these ecosystems were hardy. Due to the motion of tectonic plates, the community preserved in the Guiyang biota was located in the tropics during the early Triassic. At that time, the temperature of the sea surface was nearly 35⁰ Celsius, and past research had suggested many organisms may have migrated away to escape the heat. But, the discovery of the Guiyang biota challenges that, Foster says. Sea creatures “are tolerating it somehow, they’re adapting.”

      According to Dai, the fossils may be evidence that the roots of today’s marine ecosystems took hold shortly after the Great Dying. “These groups are related to modern fish, lobsters and shrimps, their ancestors,” he says. “The oldest time we can find similar seafood to today is [in the time of] the Guiyang biota.”

      But Roopnarine is skeptical. It remains to be seen exactly how the Guiyang biota connects to today’s ecosystems, he says. The fossil assemblage could represent an ephemeral collective of life rather than a stable community, he adds, pointing out that ammonoids and conodonts went extinct.

      Further work will help resolve the many questions unearthed with the Guiyang biota, Dai says. He and his colleagues plan to head back into the field this summer for the first time since 2019. When asked if he’ll be keeping his eyes peeled for another lobster, he responds: “Of course.” More

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      Many plans for green infrastructure risk leaving vulnerable people out

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      If you’ve noticed more lush medians and plant-covered roofs in cities, it’s not your imagination.

      Incorporating more natural elements in urban landscapes is a growing management solution for the planet’s increasing climate hazards (SN: 3/10/22). Rain gardens, green roofs and landscaped drainage ditches are all examples of what’s known as green infrastructure, and are used to manage stormwater and mitigate risks like flooding and extreme heat. These strategies sometimes double as a community resource, such as a recreational space.

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      But a major problem with green infrastructure is that the planning processes for the projects often fail to consider equity and inclusion, says Timon McPhearson, an urban ecologist and director of the Urban Systems Lab in New York City, which researches how to build more equitable, resilient and sustainable cities. Without an eye on equity, plans might exclude those most vulnerable to climate disasters, which typically include low-income communities or minority groups (SN: 2/28/22).

      There has been talk of fostering equity and inclusion in urban planning for some time, McPhearson says, but he wanted to know if there had been any follow-through. After analyzing 122 formal plans from 20 major U.S. cities, including Atlanta, Detroit and Sacramento, he and colleagues found that most government-affiliated green infrastructure plans are falling short. The researchers focused on plans produced or directly supervised by city governments, as non-profit organizations tend to be more inclusive, the study says.

      Over 90 percent of plans didn’t use inclusive processes to design or implement green infrastructure projects, meaning communities targeted for upgrades often didn’t have a chance to weigh in with their needs throughout the process. What’s more, only 10 percent of plans identified causes of inequality and vulnerability in their communities. That matters because without acknowledging the roots of injustices, planners are unable to potentially address them in future projects. And only around 13 percent of plans even defined equity or justice, the researchers report in the January Landscape and Urban Planning.

      Such inadequate plans can perpetuate existing inequalities that are part of an “ongoing legacy of historically racist policies,” McPhearson says, including limited access to heat- and pollution-relieving green spaces or proper stormwater management.

      “We have an opportunity with green infrastructure to invest in a way that can help solve multiple urban problems,” McPhearson says. “But only if we focus it in the places where there is the most need.”

      One reason behind poor urban planning practices is a lack of recognition that infrastructure can be harmful, says Yvette Lopez-Ledesma, the senior director for community-led conservation at The Wilderness Society in Los Angeles, who wasn’t involved in the study. For instance, when cities build stormwater channels but not bridges, locals are left without a way to safely cross. City planners also often lack the training and education to implement more inclusive methods.

      But there’s hope. The researchers identified three areas that need more work. First, city planners need to clearly define equity and justice in planning documents to help guide their work. They also need to change planning practices to focus on inclusion by keeping communities informed and supporting their participation throughout the planning, decision-making and implementation processes. And plans need to address current and potential causes of inequality: For example, acknowledging sources of gentrification and identifying how green infrastructure could contribute to gentrification further if officials aren’t careful (SN: 4/18/19).   

      “If equity isn’t centered in your plans, then inequity is,” Lopez-Ledesma says. “You could be doing more harm.” More

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      A new metric of extinction risk considers how cultures care for species

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      In shallow coastal waters of the Indian and Pacific oceans, a seagrass-scrounging cousin of the manatee is in trouble. Environmental strains like pollution and habitat loss pose a major threat to dugong (Dugong dugon) survival, so much so that in December, the International Union for Conservation of Nature upgraded the species’ extinction risk status to vulnerable. Some populations are now classified as endangered or critically endangered.

      If that weren’t bad enough, the sea cows are at risk of losing the protection of a group who has long looked after them: the Torres Strait Islanders. These Indigenous people off the coast of Australia historically have been stewards of the dugong populations there, sustainably hunting the animals and monitoring their numbers. But the Torres Strait Islanders are also threatened, in part because sea levels are rising and encroaching on their communities, and warmer air and sea temperatures are making it difficult for people to live in the region.

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      This situation isn’t unique to dugongs. A global analysis of 385 culturally important plant and animal species found that 68 percent were both biologically vulnerable and at risk of losing their cultural protections, researchers report January 3 in the Proceedings of the National Academy of Sciences.

      The findings clearly illustrate that biology shouldn’t be the primary factor in shaping conservation policy, says cultural anthropologist Victoria Reyes-García. When a culture dwindles, the species that are important to that culture are also under threat. To be effective, more conservation efforts need to consider the vulnerability of both the species and the people that have historically cared for them, she says.

      “A lot of the people in the conservation arena think we need to separate people from nature,” says Reyes-García, of the Catalan Institution for Research and Advanced Studies and the Autonomous University of Barcelona. But that tactic overlooks the caring relationship many cultural groups – like the Torres Strait Islanders – have with nature, she says.

      “Indigenous people, local communities, also other ethnic groups – they are good stewards of their biodiversity,” says Ina Vandebroek, an ethnobotanist at the University of the West Indies at Mona in Kingston, Jamaica, who was not involved in the work. “They have knowledge, deep knowledge, about their environments that we really cannot overlook.”

      One way to help shift conservation efforts is to give species a “biocultural status,” which would provide a fuller picture of their vulnerability, Reyes-García and colleagues say. In the study, the team used existing language vitality research to determine a culture’s risk of disappearing: The more a cultural group’s language use declines, the more that culture is threatened. And the more a culture is threatened, the more culturally vulnerable its important species are. Researchers then combined a species’ cultural and biological vulnerability to arrive at its biocultural status. In the dugong’s case, its biocultural status is endangered, meaning it is more at risk than its IUCN categorization suggests.

      This intersectional approach to conservation can help species by involving the people that have historically cared for them (SN: 3/2/22). It can also highlight when communities need support to continue their stewardship, Reyes-García says. She hopes this new framework will spark more conservation efforts that recognize local communities’ rights and encourage their participation – leaning into humans’ connection with nature instead of creating more separation (SN: 3/8/22).       More

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      It’s possible to reach net-zero carbon emissions. Here’s how

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      Patricia Hidalgo-Gonzalez saw the future of energy on a broiling-hot day last September.

      An email alert hit her inbox from the San Diego Gas & Electric Company. “Extreme heat straining the grid,” read the message, which was also pinged as a text to 27 million people. “Save energy to help avoid power interruptions.”

      It worked. People cut their energy use. Demand plunged, blackouts were avoided and California successfully weathered a crisis exacerbated by climate change. “It was very exciting to see,” says Hidalgo-Gonzalez, an electrical engineer at the University of California, San Diego who studies renewable energy and the power grid.

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      This kind of collective societal response, in which we reshape how we interact with the systems that provide us energy, will be crucial as we figure out how to live on a changing planet.

      Earth has warmed at least 1.1 degrees Celsius since the 19th century, when the burning of coal, oil and other fossil fuels began belching heat-trapping gases such as carbon dioxide into the atmosphere. Scientists agree that only drastic action to cut emissions can keep the planet from blasting past 1.5 degrees of warming — a threshold beyond which the consequences become even more catastrophic than the rising sea levels, extreme weather and other impacts the world is already experiencing.

      The goal is to achieve what’s known as net-zero emissions, where any greenhouse gases still entering the atmosphere are balanced by those being removed — and to do it as soon as we can.

      Scientists say it is possible to swiftly transform the ways we produce and consume energy. To show the way forward, researchers have set out paths toward a world where human activities generate little to no carbon dioxide and other greenhouse gases — a decarbonized economy.

      The key to a decarbonized future lies in producing vast amounts of new electricity from sources that emit little to none of the gases, such as wind, solar and hydropower, and then transforming as much of our lives and our industries as possible to run off those sources. Clean electricity needs to power not only the planet’s current energy use but also the increased demands of a growing global population.

      Once humankind has switched nearly entirely to clean electricity, we will also have to counter­balance the carbon dioxide we still emit — yes, we will still emit some — by pulling an equivalent amount of carbon dioxide out of the atmosphere and storing it somewhere permanently.

      Achieving net-zero emissions won’t be easy. Getting to effective and meaningful action on climate change requires overcoming decades of inertia and denial about the scope and magnitude of the problem. Nations are falling well short of existing pledges to reduce emissions, and global warming remains on track to charge past 1.5 degrees perhaps even by the end of this decade.

      Yet there is hope. The rate of growth in CO2 emissions is slowing globally — down from 3 percent annual growth in the 2000s to half a percent annual growth in the last decade, according to the Global Carbon Project, which quantifies greenhouse gas emissions.

      There are signs annual emissions could start shrinking. And over the last two years, the United States, by far the biggest cumulative contributor to global warming, has passed several pieces of federal legislation that include financial incentives to accelerate the transition to clean energy. “We’ve never seen anything at this scale,” says Erin Mayfield, an energy researcher at Dartmouth College.

      Though the energy transition will require many new technologies, such as innovative ways to permanently remove carbon from the atmosphere, many of the solutions, such as wind and solar power, are in hand — “stuff we already have,” Mayfield says.

      The current state of carbon dioxide emissions

      Of all the emissions that need to be slashed, the most important is carbon dioxide, which comes from many sources such as cars and trucks and coal-burning power plants. The gas accounted for 79 percent of U.S. greenhouse gas emissions in 2020. The next most significant greenhouse gas, at 11 percent of emissions in the United States, is methane, which comes from oil and gas operations as well as livestock, landfills and other land uses.

      The amount of methane may seem small, but it is mighty — over the short term, methane is more than 80 times as efficient at trapping heat as carbon dioxide is, and methane’s atmospheric levels have nearly tripled in the last two centuries. Other greenhouse gases include nitrous oxides, which come from sources such as applying fertilizer to crops or burning fuels and account for 7 percent of U.S. emissions, and human-made fluorinated gases such as hydrofluorocarbons that account for 3 percent.

      Globally, emissions are dominated by large nations that produce lots of energy. The United States alone emits around 5 billion metric tons of carbon dioxide each year. It is responsible for most of the greenhouse gas emissions throughout history and ceded the spot for top annual emitter to China only in the mid-2000s. India ranks third.

      Because of the United States’ role in producing most of the carbon pollution to date, many researchers and advocates argue that it has the moral responsibility to take the global lead on cutting emissions. And the United States has the most ambitious goals of the major emitters, at least on paper. President Joe Biden has said the country is aiming to reach net-zero emissions by 2050. Leaders in China and India have set net-zero goals of 2060 and 2070, respectively.

      Under the auspices of a 2015 international climate change treaty known as the Paris agreement, 193 nations plus the European Union have pledged to reduce their emissions. The agreement aims to keep global warming well below 2 degrees, and ideally to 1.5 degrees, above preindustrial levels. But it is insufficient. Even if all countries cut their emissions as much as they have promised under the Paris agreement, the world would likely blow past 2 degrees of warming before the end of this century. 

      Every nation continues to find its own path forward. “At the end of the day, all the solutions are going to be country-specific,” says Sha Yu, an earth scientist at the Pacific Northwest National Laboratory and University of Maryland’s Joint Global Change Research Institute in College Park, Md. “There’s not a universal fix.”

      But there are some common themes for how to accomplish this energy transition — ways to focus our efforts on the things that will matter most. These are efforts that go beyond individual consumer choices such as whether to fly less or eat less meat. They instead penetrate every aspect of how society produces and consumes energy.

      Such massive changes will need to overcome a lot of resistance, including from companies that make money off old forms of energy as well as politicians and lobbyists. But if society can make these changes, it will rank as one of humanity’s greatest accomplishments. We will have tackled a problem of our own making and conquered it.

      Here’s a look at what we’ll need to do.

      Make as much clean electricity as possible

      To meet the need for energy without putting carbon dioxide into the atmosphere, countries would need to dramatically scale up the amount of clean energy they produce. Fortunately, most of that energy would be generated by technologies we already have — renewable sources of energy including wind and solar power.

      “Renewables, far and wide, are the key pillar in any net-zero scenario,” says Mayfield, who worked on an influential 2021 report from Princeton University’s Net-Zero America project, which focused on the U.S. economy.

      The Princeton report envisions wind and solar power production roughly quadrupling by 2030 to get the United States to net-zero emissions by 2050. That would mean building many new solar and wind farms, so many that in the most ambitious scenario, wind turbines would cover an area the size of Arkansas, Iowa, Kansas, Missouri, Nebraska and Oklahoma combined.

      Such a scale-up is only possible because prices to produce renewable energy have plunged. The cost of wind power has dropped nearly 70 percent, and solar power nearly 90 percent, over the last decade in the United States. “That was a game changer that I don’t know if some people were expecting,” Hidalgo-Gonzalez says.

      Globally the price drop in renewables has allowed growth to surge; China, for instance, installed a record 55 gigawatts of solar power capacity in 2021, for a total of 306 gigawatts or nearly 13 percent of the nation’s installed capacity to generate electricity. China is almost certain to have had another record year for solar power installations in 2022.

      Challenges include figuring out ways to store and transmit all that extra electricity, and finding locations to build wind and solar power installations that are acceptable to local communities. Other types of low-carbon power, such as hydropower and nuclear power, which comes with its own public resistance, will also likely play a role going forward.

      Get efficient and go electric

      The drive toward net-zero emissions also requires boosting energy efficiency across industries and electrifying as many aspects of modern life as possible, such as transportation and home heating.

      Some industries are already shifting to more efficient methods of production, such as steelmaking in China that incorporates hydrogen-based furnaces that are much cleaner than coal-fired ones, Yu says. In India, simply closing down the most inefficient coal-burning power plants provides the most bang for the buck, says Shayak Sengupta, an energy and policy expert at the Observer Research Foundation America think tank in Washington, D.C. “The list has been made up,” he says, of the plants that should close first, “and that’s been happening.”

      To achieve net-zero, the United States would need to increase its share of electric heat pumps, which heat houses much more cleanly than gas- or oil-fired appliances, from around 10 percent in 2020 to as much as 80 percent by 2050, according to the Princeton report. Federal subsidies for these sorts of appliances are rolling out in 2023 as part of the new Inflation Reduction Act, legislation that contains a number of climate-related provisions.

      Shifting cars and other vehicles away from burning gasoline to running off of electricity would also lead to significant emissions cuts. In a major 2021 report, the National Academies of Sciences, Engineering and Medicine said that one of the most important moves in decarbonizing the U.S. economy would be having electric vehicles account for half of all new vehicle sales by 2030. That’s not impossible; electric car sales accounted for nearly 6 percent of new sales in the United States in 2022, which is still a low number but nearly double the previous year.

      Make clean fuels

      Some industries such as manufacturing and transportation can’t be fully electrified using current technologies — battery powered airplanes, for instance, will probably never be feasible for long-duration flights. Technologies that still require liquid fuels will need to switch from gas, oil and other fossil fuels to low-carbon or zero-carbon fuels.

      One major player will be fuels extracted from plants and other biomass, which take up carbon dioxide as they grow and emit it when they die, making them essentially carbon neutral over their lifetime. To create biofuels, farmers grow crops, and others process the harvest in conversion facilities into fuels such as hydrogen. Hydrogen, in turn, can be substituted for more carbon-intensive substances in various industrial processes such as making plastics and fertilizers — and maybe even as fuel for airplanes someday.

      In one of the Princeton team’s scenarios, the U.S. Midwest and Southeast would become peppered with biomass conversion plants by 2050, so that fuels can be processed close to where crops are grown. Many of the biomass feedstocks could potentially grow alongside food crops or replace other, nonfood crops.

      Cut methane and other non-CO2 emissions

      Greenhouse gas emissions other than carbon dioxide will also need to be slashed. In the United States, the majority of methane emissions come from livestock, landfills and other agricultural sources, as well as scattered sources such as forest fires and wetlands. But about one-third of U.S. methane emissions come from oil, gas and coal operations. These may be some of the first places that regulators can target for cleanup, especially “super emitters” that can be pinpointed using satellites and other types of remote sensing.

      In 2021, the United States and the European Union unveiled what became a global methane pledge endorsed by 150 countries to reduce emissions. There is, however, no enforcement of it yet. And China, the world’s largest methane emitter, has not signed on.

      Nitrous oxides could be reduced by improving soil management techniques, and fluorinated gases by finding alternatives and improving production and recycling efforts.

      Sop up as much CO2 as possible

      Once emissions have been cut as much as possible, reaching net-zero will mean removing and storing an equivalent amount of carbon to what society still emits.

      One solution already in use is to capture carbon dioxide produced at power plants and other industrial facilities and store it permanently somewhere, such as deep underground. Globally there are around 35 such operations, which collectively draw down around 45 million tons of carbon dioxide annually. About 200 new plants are on the drawing board to be operating by the end of this decade, according to the International Energy Agency.

      The Princeton report envisions carbon capture being added to almost every kind of U.S. industrial plant, from cement production to biomass conversion. Much of the carbon dioxide would be liquefied and piped along more than 100,000 kilometers of new pipelines to deep geologic storage, primarily along the Texas Gulf Coast, where underground reservoirs can be used to trap it permanently. This would be a massive infrastructure effort. Building this pipeline network could cost up to $230 billion, including $13 billion for early buy-in from local communities and permitting alone.

      Another way to sop up carbon is to get forests and soils to take up more. That could be accomplished by converting crops that are relatively carbon-intensive, such as corn to be used in ethanol, to energy-rich grasses that can be used for more efficient biofuels, or by turning some cropland or pastures back into forest. It’s even possible to sprinkle crushed rock onto croplands, which accelerates natural weathering processes that suck carbon dioxide out of the atmosphere.

      Another way to increase the amount of carbon stored in the land is to reduce the amount of the Amazon rainforest that is cut down each year. “For a few countries like Brazil, preventing deforestation will be the first thing you can do,” Yu says.

      When it comes to climate change, there’s no time to waste

      The Princeton team estimates that the United States would need to invest at least an additional $2.5 trillion over the next 10 years for the country to have a shot at achieving net-zero emissions by 2050. Congress has begun ramping up funding with two large pieces of federal legislation it passed in 2021 and 2022. Those steer more than $1 trillion toward modernizing major parts of the nation’s economy over a decade — including investing in the energy transition to help fight climate change.

      Between now and 2030, solar and wind power, plus increasing energy efficiency, can deliver about half of the emissions reductions needed for this decade, the International Energy Agency estimates. After that, the primary drivers would need to be increasing electrification, carbon capture and storage, and clean fuels such as hydrogen.

      A lot of the technology needed for a future with fewer carbon dioxide emissions is already available. The Ivanpah Solar Electric Generating System in the Mojave Desert focuses sunlight to generate steam. That steam spins turbines to make electricity.ADAMKAZ/E+/GETTY IMAGES

      The trick is to do all of this without making people’s lives worse. Developing nations need to be able to supply energy for their economies to develop. Communities whose jobs relied on fossil fuels need to have new economic opportunities.

      Julia Haggerty, a geographer at Montana State University in Bozeman who studies communities that are dependent on natural resources, says that those who have money and other resources to support the transition will weather the change better than those who are under-resourced now. “At the landscape of states and regions, it just remains incredibly uneven,” she says.

      The ongoing energy transition also faces unanticipated shocks such as Russia’s invasion of Ukraine, which sent energy prices soaring in Europe, and the COVID-19 pandemic, which initially slashed global emissions but later saw them rebound.

      But the technologies exist for us to wean our lives off fossil fuels. And we have the inventiveness to develop more as needed. Transforming how we produce and use energy, as rapidly as possible, is a tremendous challenge — but one that we can meet head-on. For Mayfield, getting to net-zero by 2050 is a realistic goal for the United States. “I think it’s possible,” she says. “But it doesn’t mean there’s not a lot more work to be done.” More

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      Rare earth elements could be pulled from coal waste

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      In Appalachia’s coal country, researchers envision turning toxic waste into treasure. The pollution left behind by abandoned mines is an untapped source of rare earth elements.

      Rare earths are a valuable set of 17 elements needed to make everything from smartphones and electric vehicles to fluorescent bulbs and lasers. With global demand skyrocketing and China having a near-monopoly on rare earth production — the United States has only one active mine — there’s a lot of interest in finding alternative sources, such as ramping up recycling.

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      Pulling rare earths from coal waste offers a two-for-one deal: By retrieving the metals, you also help clean up the pollution.

      Long after a coal mine closes, it can leave a dirty legacy. When some of the rock left over from mining is exposed to air and water, sulfuric acid forms and pulls heavy metals from the rock. This acidic soup can pollute waterways and harm wildlife.

      Recovering rare earths from what’s called acid mine drainage won’t single-handedly satisfy rising demand for the metals, acknowledges Paul Ziemkiewicz, director of the West Virginia Water Research Institute in Morgantown. But he points to several benefits.

      Unlike ore dug from typical rare earth mines, the drainage is rich with the most-needed rare earth elements. Plus, extraction from acid mine drainage also doesn’t generate the radioactive waste that’s typically a by-product of rare earth mines, which often contain uranium and thorium alongside the rare earths. And from a practical standpoint, existing facilities to treat acid mine drainage could be used to collect the rare earths for processing. “Theoretically, you could start producing tomorrow,” Ziemkiewicz says.

      From a few hundred sites already treating acid mine drainage, nearly 600 metric tons of rare earth elements and cobalt — another in-demand metal — could be produced annually, Ziemkiewicz and colleagues estimate.

      Currently, a pilot project in West Virginia is taking material recovered from an acid mine drainage treatment site and extracting and concentrating the rare earths.

      If such a scheme proves feasible, Ziemkiewicz envisions a future in which cleanup sites send their rare earth hauls to a central facility to be processed, and the elements separated. Economic analyses suggest this wouldn’t be a get-rich scheme. But, he says, it could be enough to cover the costs of treating the acid mine drainage. More

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      Recycling rare earth elements is hard. Science is trying to make it easier

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      Our modern lives depend on rare earth elements, and someday soon we may not have enough to meet growing demand.

      Because of their special properties, these 17 metallic elements are crucial ingredients in computer screens, cell phones and other electronics, compact fluorescent lamps, medical imaging machines, lasers, fiber optics, pigments, polishing powders, industrial catalysts – the list goes on and on (SN Online: 1/16/23). Notably rare earths are an essential part of the high-powered magnets and rechargeable batteries in the electric vehicles and renewable energy technologies needed to get the world to a low- or zero-carbon future.

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      In 2021, the world mined 280,000 metric tons of rare earths — roughly 32 times as much as was mined in the mid-1950s. And demand is only going to increase. By 2040, experts estimate, we’ll need up to seven times as much rare earths as we do today.

      Satisfying that appetite won’t be easy. Rare earth elements are not found in concentrated deposits. Miners must excavate huge amounts of ore, subject it to physical and chemical processes to concentrate the rare earths, and then separate them. The transformation is energy intensive and dirty, requiring toxic chemicals and often generating a small amount of radioactive waste that must be safely disposed of. Another concern is access: China has a near monopoly on both mining and processing; the United States has just one active mine (SN Online: 1/1/23).

      For most of the jobs rare earths do, there are no good substitutes. So to help meet future demand and diversify who controls the supply — and perhaps even make rare earth recovery “greener” — researchers are looking for alternatives to conventional mining.   

      Proposals include everything from extracting the metals from coal waste to really out-there ideas like mining the moon. But the approach most likely to make an immediate dent is recycling. “Recycling is going to play a very important and central role,” says Ikenna Nlebedim, a materials scientist at Ames National Laboratory in Iowa and the Department of Energy’s Critical Materials Institute. “That’s not to say we’re going to recycle our way out of the critical materials challenge.”

      Still, in the rare earth magnets market, for instance, by about 10 years from now, recycling could satisfy as much as a quarter of the demand for rare earths, based on some estimates. “That’s huge,” he says.

      But before the rare earths in an old laptop can be recycled as regularly as the aluminum in an empty soda can, there are technological, economic and logistical obstacles to overcome.

      Why are rare earths so challenging to extract?

      Recycling seems like an obvious way to get more rare earths. It’s standard practice in the United States and Europe to recycle from 15 to 70 percent of other metals, such as iron, copper, aluminum, nickel and tin. Yet today, only about 1 percent of rare earth elements in old products are recycled, says Simon Jowitt, an economic geologist at the University of Nevada, Las Vegas.

      “Copper wiring can be recycled into more copper wiring. Steel can just be recycled into more steel,” he says. But a lot of rare earth products are “inherently not very recyclable.”

      Rare earths are often blended with other metals in touch screens and similar products, making removal difficult. In some ways, recycling rare earths from tossed-out items resembles the challenge of extracting them from ore and separating them from each other. Traditional rare earth recycling methods also require hazardous chemicals such as hydrochloric acid and a lot of heat, and thus a lot of energy. On top of the environmental footprint, the cost of recovery may not be worth the effort given the small yield of rare earths. A hard disk drive, for instance, might contain just a few grams; some products offer just milligrams.

      Chemists and materials scientists, though, are trying to develop smarter recycling approaches. Their techniques put microbes to work, ditch the acids of traditional methods or attempt to bypass extraction and separation.

      Microbial partners can help recycle rare earths

      One approach leans on microscopic partners. Gluconobacter bacteria naturally produce organic acids that can pull rare earths, such as lanthanum and cerium, from spent catalysts used in petroleum refining or from fluorescent phosphors used in lighting. The bacterial acids are less environmentally harmful than hydrochloric acid or other traditional metal-leaching acids, says Yoshiko Fujita, a biogeochemist at Idaho National Laboratory in Idaho Falls. Fujita leads research into reuse and recycling at the Critical Materials Institute. “They can also be degraded naturally,” she says.

      In experiments, the bacterial acids can recover only about a quarter to half of the rare earths from spent catalysts and phosphors. Hydrochloric acid can do much better — in some cases extracting as much as 99 percent. But bio-based leaching might still be profitable, Fujita and colleagues reported in 2019 in ACS Sustainable Chemistry & Engineering.

      In a hypothetical plant recycling 19,000 metric tons of used catalyst a year, the team estimated annual revenues to be roughly $1.75 million. But feeding the bacteria that produce the acid on-site is a big expense. In a scenario in which the bacteria are fed refined sugar, total costs for producing the rare earths are roughly $1.6 million a year, leaving around just $150,000 in profits. Switching from sugar to corn stalks, husks and other harvest leftovers, however, would slash costs by about $500,000, raising profits to about $650,000.

      One experimental recycling approach uses organic acids made by bacteria to extract rare earths from waste products. This reactor at the Idaho National Laboratory prepares an organic acid mixture for such recycling.Idaho National Lab

      Other microbes can also help extract rare earths and take them even further. A few years ago, researchers discovered that some bacteria that metabolize rare earths produce a protein that preferentially grabs onto these metals. This protein, lanmodulin, can separate rare earths from each other, such as neodymium from dysprosium — two components of rare earth magnets. A lanmodulin-based system might eliminate the need for the many chemical solvents typically used in such separation. And the waste left behind — the protein — would be biodegradable. But whether the system will pan out on a commercial scale is unknown.

      How to pull rare earths from discarded magnets

      Another approach already being commercialized skips the acids and uses copper salts to pull the rare earths from discarded magnets, a valuable target. Neodymium-iron-boron magnets are about 30 percent rare earth by weight and the single largest application of the metals in the world. One projection suggests that recovering the neodymium in magnets from U.S. hard disk drives alone could meet up about 5 percent of the world’s demand outside of China before the end of the decade.

      Nlebedim led a team that developed a technique that uses copper salts to leach rare earths out of shredded electronic waste that contains magnets. Dunking the e-waste in a copper salt solution at room temperature dissolves the rare earths in the magnets. Other can be scooped out for their own recycling, and the copper can be reused to make more salt solution. Next, the rare earths are solidified and, with the help of additional chemicals and heating, transformed into powdered minerals called rare earth oxides. The process, which has also been used on material left over from magnet manufacturing that typically goes to waste, can recover 90 to 98 percent of the rare earths, and the material is pure enough to make new magnets, Nlebedim’s team has demonstrated.

      In a best-case scenario, using this method to recycle 100 tons of leftover magnet material might produce 32 tons of rare earth oxides and net more than $1 million in profits, an economic analysis of the method suggests.

      That study also evaluated the approach’s environmental impacts. Compared with producing one kilogram of rare earth oxide via one of the main types of mining and processing currently used in China, the copper salt method has less than half the carbon footprint. It produces an average of about 50 kilograms of carbon dioxide equivalent per kilogram of rare earth oxide versus 110, Nlebedim’s team reported in 2021 in ACS Sustainable Chemistry & Engineering.

      But it’s not necessarily greener than all forms of mining. One sticking point is that the process requires toxic ammonium hydroxide and roasting, which consumes a lot of energy, and it still releases some carbon dioxide. Nlebedim’s group is now tweaking the technique. “We want to decarbonize the process and make it safer,” he says.

      Meanwhile, the technology seems promising enough that TdVib, an Iowa company that designs and manufactures magnetic materials and products, has licensed it and built a pilot plant. The initial aim is to produce two tons of rare earth oxides per month, says Daniel Bina, TdVib’s president and CEO. The plant will recycle rare earths from old hard disk drives from data centers.

      Noveon Magnetics, a company in San Marcos, Texas, is already making recycled neodymium-iron-boron magnets. In typical magnet manufacturing, the rare earths are mined, transformed into metal alloys, milled into a fine powder, magnetized and formed into a magnet. Noveon knocks out those first two steps, says company CEO Scott Dunn.

      After demagnetizing and cleaning discarded magnets, Noveon directly mills them into a powder before building them back up as new magnets. Unlike with other recycling methods, there’s no need to extract and separate the rare earths out first. The final product can be more than 99 percent recycled magnet, Dunn says, with a small addition of virgin rare earth elements — the “secret sauce,” as he puts it — that allows the company to fine-tune the magnets’ attributes.

      Compared with traditional magnet mining and manufacturing, Noveon’s method cuts energy use by about 90 percent, Miha Zakotnik, Noveon’s chief technology officer, and other researchers reported in 2016 in Environmental Technology & Innovation. Another 2016 analysis estimated that for every kilogram of magnet produced via Noveon’s method, about 12 kilograms of carbon dioxide equivalent are emitted. That’s about half as much of the greenhouse gas as conventional magnets.

      Dunn declined to share what volume of magnets Noveon currently produces or how much its magnets cost. But the magnets are being used in some industrial applications, for pumps, fans and compressors, as well as some consumer power tools and other electronics.

      To help with recycling, Apple developed the robot Daisy (shown), which can dismantle 23 models of iPhones. Other robots in the works — Taz and Dave — will specialize in recovering rare earth magnets.Apple

      Rare earth recycling has logistical hurdles

      Even as researchers clear technological hurdles, there are still logistical barriers to recycling. “We don’t have the systems for collecting end-of-life products that have rare earths in them,” Fujita says, “and there’s the cost of dismantling those products.” For a lot of e-waste, before rare earth recycling can begin, you have to get to the bits that contain those precious metals.

      Noveon has a semiautomated process for removing magnets from hard disk drives and other electronics.

      Apple is also trying to automate the recycling process. The company’s Daisy robot can dismantle iPhones. And in 2022, Apple announced a pair of robots called Taz and Dave that facilitate the recycling of rare earths. Taz can gather magnet-containing modules that are typically lost during the shredding of electronics. Dave can recover magnets from taptic engines, Apple’s technology for providing users with tactile feedback when, say, tapping an iPhone screen.

      Even with robotic aids, it would still be a lot easier if companies just designed products in a way that made recycling easy, Fujita says.

      No matter how good recycling gets, Jowitt sees no getting around the need to ramp up mining to feed our rare earth–hungry society. But he agrees recycling is necessary. “We’re dealing with intrinsically finite resources,” he says. “Better we try and extract what we can rather than just dumping it in the landfill.” More

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      Cyclones in the Arctic are becoming more intense and frequent

      by

      CHICAGO – In January 2022, a cyclone blitzed a large expanse of ice-covered ocean between Greenland and Russia. Frenzied gusts galvanized 8-meter-tall waves that pounded the region’s hapless flotillas of sea ice, while a bombardment of warm rain and a surge of southerly heat laid siege from the air.

      Six days after the assault began, about a quarter, or roughly 400,000 square kilometers, of the vast area’s sea ice had disappeared, leading to a record weekly loss for the region.

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      The storm is the strongest Arctic cyclone ever documented. But it may not hold that title for long. Cyclones in the Arctic have become more frequent and intense in recent decades, posing risks to both sea ice and people, researchers reported December 13 at the American Geophysical Union’s fall meeting. “This trend is expected to persist as the region continues to warm rapidly in the future,” says climate scientist Stephen Vavrus of the University of Wisconsin–Madison.

      Rapid Arctic warming and more destructive storms

      The Arctic Circle is warming about four times as fast as the rest of Earth (SN: 8/11/22). A major driver is the loss of sea ice due to human-caused climate change. The floating ice reflects far more solar radiation back into space than naked seas do, influencing the global climate (SN: 10/14/21). During August, the heart of the sea ice melting season, cyclones have been observed to amplify sea ice losses on average, exacerbating warming.

      There’s more: Like hurricanes can ravage regions farther south, boreal vortices can threaten people living and traveling in the Arctic (SN: 12/11/19). As the storms intensify, “stronger winds pose a risk for marine navigation by generating higher waves,” Vavrus says, “and for coastal erosion, which has already become a serious problem throughout much of the Arctic and forced some communities to consider relocating inland.”

      Climate change is intensifying storms farther south (SN: 11/11/20). But it’s unclear how Arctic cyclones might be changing as the world warms. Some previous research suggested that pressures, on average, in Arctic cyclones’ cores have dropped in recent decades. That would be problematic, as lower pressures generally mean more intense storms, with “stronger winds, larger temperature variations and heavier rainfall [and] snowfall,” says atmospheric scientist Xiangdong Zhang of the University of Alaska Fairbanks.

      But inconsistencies between analyses had prevented a clear trend from emerging, Zhang said at the meeting. So he and his colleagues aggregated a comprehensive record, spanning 1950 to 2021, of Arctic cyclone timing, intensity and duration.

      Arctic cyclone activity has intensified in strength and frequency over recent decades, Zhang reported. Pressures in the hearts of today’s boreal vortices are on average about 9 millibars lower than in the 1950s. For context, such a pressure shift would be roughly equivalent to bumping a strong category 1 hurricane well into category 2 territory. And vortices became more frequent during winters in the North Atlantic Arctic and during summers in the Arctic north of Eurasia.

      What’s more, August cyclones appear to be damaging sea ice more than in the past, said meteorologist Peter Finocchio of the U.S. Naval Research Laboratory in Monterey, Calif. He and his colleagues compared the response of northern sea ice to summer cyclones during the 1990s and the 2010s.

      August vortices in the latter decade were followed by a 10 percent loss of sea ice area on average, up from the earlier decade’s 3 percent loss on average. This may be due, in part, to warmer water upwelling from below, which can melt the ice pack’s underbelly, and from winds pushing the thinner, easier-to-move ice around, Finocchio said.

      Stronger spring storms spell trouble too

      With climate change, cyclones may continue intensifying in the spring too, climate scientist Chelsea Parker said at the meeting. That’s a problem because spring vortices can prime sea ice for later summer melting.

      Parker, of NASA’s Goddard Space Flight Center in Greenbelt, Md., and her colleagues ran computer simulations of spring cyclone behavior in the Arctic under past, present and projected climate conditions. By the end of the century, the maximum near-surface wind speeds of spring cyclones — around 11 kilometers per hour today — could reach 60 km/h, the researchers found. And future spring cyclones may keep swirling at peak intensity for up to a quarter of their life spans, up from around 1 percent today. The storms will probably travel farther too, the team says.

      “The diminishing sea ice cover will enable the warmer Arctic seas to fuel these storms and probably allow them to penetrate farther into the Arctic,” says Vavrus, who was not involved in the research.

      Parker and her team plan to investigate the future evolution of Arctic cyclones in other seasons, to capture a broader picture of how climate change is affecting the storms.

      For now, it seems certain that Arctic cyclones aren’t going anywhere. What’s less clear is how humankind will contend with the storms’ growing fury. More