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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

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      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

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      Sea life offers a lens for self-exploration in ‘How Far the Light Reaches’

      by

      How Far the Light ReachesSabrina ImblerLittle, Brown & Co., $27

      In How Far the Light Reaches, Sabrina Imbler shows us that the ocean, in all its mystery and dazzling glory, is queer — that is, the life that takes shape there challenges how we landlubbers perceive ways of being. This collection of essays tells the stories of 10 sea creatures, with Imbler, a queer and mixed-race writer, weaving in stories of their own family, self-discovery, sexuality and healing. The profiled animals, often thought of as strange or alien, transform into recognizable emblems of identity, community and queer joy in this delectable amalgam of memoir and science journalism.

      Imbler begins with a confession: “The truth is that I was asked to leave the Petco, but I told everyone I was banned.” Thirteen-year-old Imbler had staged a protest in the store, attempting to convince customers not to buy goldfish bowls. The bowls, Imbler writes, condemn the fish to a truncated life in a transparent coffin, in which they will die isolated, starved of oxygen and poisoned with ammonia from their own urine.

      But unencumbered by the confines of a bowl, the fish thrive. When bored pet owners dump goldfish in lakes or rivers, the fish can balloon to the size of jugs of milk. They are “so good at living they have become an ecological menace,” breeding with abandon, uprooting bottom dwellers, and fomenting bacterial growth and algal blooms, Imbler writes.

      Yet Imbler can’t help but admire the feral goldfish’s resilience: “I see something that no one expected to live not just alive but impossibly flourishing.”

      Survival among unthinkable circumstances is a theme common to all the profiled animals. Take the yeti crab (Kiwa puravida), which, after reading this book, I now proclaim a queer icon (step aside, the Babadook). In the frigid dark, about 1,000 meters below the sea surface, the crab finds solace near hydrothermal vents.

      Such hot spots foster life in a desolate wasteland. Heat and chemicals from inside the Earth sustain an ecosystem of crabs, clams, mussels, tube worms and more. There, in true queer fashion, K. puravida “dances to live,” Imbler writes. The yeti crab throws its claws in the air and waves ’em like it just don’t care. In doing so, it is “farming” the bacteria that it eats, which cling to the crab’s bristly claws. Waving the claws in a slow but steady rhythm ensures the bacteria get nutrients.

      In telling the crab’s story, Imbler reminisces on their quest to find community after moving to Seattle in 2016. Feeling alone among the mostly white people they met, Imbler discovered a monthly party called Night Crush, thrown by and for queer people of color. Night Crush became Imbler’s own hydrothermal vent — an oasis warmed by people dancing in mesh, sequins, glitter and joy. “As queer people, we get to choose our families,” Imbler writes. “Vent bacteria, tube worms, and yeti crabs just take it one step further. They choose what nourishes them.”

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      Imbler looks to the sea to explore all aspects of family. The purple octopus (Graneledone boreopacifica), for instance, offers insights on motherhood. During a four-and-a-half-year brooding period, the longest known for any animal, the octopus starves herself to death, foregoing hunting to protect her eggs (SN: 7/30/14).

      Through the octopus’ saga, Imbler reflects on their own mother, who moved to the United States from Taiwan as a child. Imbler’s mother felt like she was on “a new planet.” To survive, she learned to want to be as white and “American” as possible, and as thin as possible — traumas inherited by Imbler, who developed an eating disorder.

      In their recovery, Imbler has realized their mother’s wish for them to be thin, though damaging, was, in a way, an act of love: “She wanted me to be skinny so things would be easier. White, so things would be easier. Straight, so things would be easy, easy, easy. So that unlike her, no one would ever question my right to be here, in America.”

      A chain of salps floats off the coast of California in the Pacific Ocean.Brook Peterson/Stocktrek Images/Getty Images Plus

      It is with that same grace, clarity and tenderness that Imbler crafts the book’s other essays, whether it’s meditating on their own gender expression through the cuttlefish’s mastery of metamorphosis or examining their experience of sexual assault through the sand striker, an ambush predator of the seafloor.

      Like a goldfish confined by a bowl, I am confined by my word count and can’t say everything I want to about this must-read book. So I’ll end on one final insight. In one essay, Imbler introduces salps. These jelly-like blobs exist as a colony of hundreds of identical salps joined in a chain. The creatures do not move in one synchronized effort. “Salps allow each individual to jet at its own pace in the same general direction,” Imbler writes. “It is not as fast as coordinated strokes, but it’s more sustainable long-term, each individual sucking and spurting as it pleases.”

      This idea of one collective, made up of individuals marching toward a common cause at their own pace, is one that queer people and other marginalized groups know well — whether creating community or protesting for civil rights. And it’s a notion that Imbler imparts upon their reader: “We may all move at different paces, but we will only reach the horizon together.”

      Buy How Far the Light Reaches from Bookshop.org. Science News is a Bookshop.org affiliate and will earn a commission on purchases made from links in this article. More

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      Rare earth mining may be key to our renewable energy future. But at what cost?

      by

      In spring 1949, three prospectors armed with Geiger counters set out to hunt for treasure in the arid mountains of southern Nevada and southeastern California.

      In the previous century, those mountains yielded gold, silver, copper and cobalt. But the men were looking for a different kind of treasure: uranium. The world was emerging from World War II and careening into the Cold War. The United States needed uranium to build its nuclear weapons arsenal. Mining homegrown sources became a matter of national security.

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      After weeks of searching, the trio hit what they thought was pay dirt. Their instruments detected intense radioactivity in brownish-red veins of ore exposed in a rocky outcrop within California’s Clark Mountain Range. But instead of uranium, the brownish-red stuff turned out to be bastnaesite, a mineral bearing fluorine, carbon and 17 curious elements known collectively as rare earths. Traces of radioactive thorium, also in the ore, had set the Geiger counters pinging.

      As disappointing as that must have been, the bastnaesite still held value, and the prospectors sold their claim to the Molybdenum Corporation of America, later called Molycorp. The company was interested in mining the rare earths. During the mid-20th century, rare earth elements were becoming useful in a variety of ways: Cerium, for example, was the basis for a glass-polishing powder and europium lent luminescence to recently invented color television screens and fluorescent lamps.

      For the next few decades, the site, later dubbed Mountain Pass mine, was the world’s top source for rare earth elements, until two pressures became too much. By the late 1980s, China was intensively mining its own rare earths — and selling them at lower prices. And a series of toxic waste spills at Mountain Pass brought production at the struggling mine to a halt in 2002.

      But that wasn’t the end of the story. The green-tech revolution of the 21st century brought new attention to Mountain Pass, which later reopened and remains the only U.S. mine for rare earths.

      Rare earths are now integral to the manufacture of many carbon-neutral technologies — plus a whole host of tools that move the modern world. These elements are the building blocks of small, super­efficient permanent magnets that keep smartphones buzzing, wind turbines spinning, electric vehicles zooming and more.

      Mining U.S. sources of rare earth elements, President Joe Biden’s administration stated in February 2021, is a matter of national security.

      Rare earths are not actually rare on Earth, but they tend to be scattered throughout the crust at low concentrations. And the ore alone is worth relatively little without the complex, often environmentally hazardous processing involved in converting the ore into a usable form, says Julie Klinger, a geographer at the University of Delaware in Newark. As a result, the rare earth mining industry is wrestling with a legacy of environmental problems.

      Rare earths are mined by digging vast open pits in the ground, which can contaminate the environment and disrupt ecosystems. When poorly regulated, mining can produce wastewater ponds filled with acids, heavy metals and radioactive material that might leak into groundwater. Processing the raw ore into a form useful to make magnets and other tech is a lengthy effort that takes large amounts of water and potentially toxic chemicals, and produces voluminous waste.

      “We need rare earth elements … to help us with the transition to a climate-safe future,” says Michele Bustamante, a sustainability researcher at the Natural Resources Defense Council in Washington, D.C. Yet “everything that we do when we’re mining is impactful environmentally,” Bustamante says.

      But there are ways to reduce mining’s footprint, says Thomas Lograsso, a metallurgist at the Ames National Laboratory in Iowa and the director of the Critical Materials Institute, a Department of Energy research center. Researchers are investigating everything from reducing the amount of waste produced during the ore processing to improving the efficiency of rare earth element separation, which can also cut down on the amount of toxic waste. Scientists are also testing alternatives to mining, such as recycling rare earths from old electronics or recovering them from coal waste.

      Much of this research is in partnership with the mining industry, whose buy-in is key, Lograsso says. Mining companies have to be willing to invest in making changes. “We want to make sure that the science and innovations that we do are driven by industry needs, so that we’re not here developing solutions that nobody really wants,” he says.

      Klinger says she’s cautiously optimistic that the rare earth mining industry can become less polluting and more sustainable, if such solutions are widely adopted. “A lot of gains come from the low-hanging fruit,” she says. Even basic hardware upgrades to improve insulation can reduce the fuel required to reach the high temperatures needed for some processing. “You do what you [can].”

      The environmental impact of rare earth mining

      Between the jagged peaks of California’s Clark range and the Nevada border sits a broad, flat, shimmering valley known as the Ivanpah Dry Lake. Some 8,000 years ago, the valley held water year-round. Today, like many such playas in the Mojave Desert, the lake is ephemeral, winking into appearance only after an intense rain and flash flooding. It’s a beautiful, stark place, home to endangered desert tortoises and rare desert plants like Mojave milkweed.

      From about 1984 to 1998, the Ivanpah Dry Lake was also a holding pen for wastewater piped in from Mountain Pass. The wastewater was a by-product of chemical processing to concentrate the rare earth elements in the mined rock, making it more marketable to companies that could then extract those elements to make specific products. Via a buried pipeline, the mine sent wastewater to evaporation ponds about 23 kilometers away, in and around the dry lake bed.

      The pipeline repeatedly ruptured over the years. At least 60 separate spills dumped an estimated 2,000 metric tons of wastewater containing radioactive thorium into the valley. Federal officials feared that local residents and visitors to the nearby Mojave National Preserve might be at risk of exposure to that thorium, which could lead to increased risk of lung, pancreatic and other cancers.

      Unocal Corporation, which had acquired Molycorp in 1977, was ordered to clean up the spill in 1997, and the company paid over $1.4 million in fines and settlements. Chemical processing of the raw ore ground to a halt. Mining operations stopped shortly afterward.

      Half a world away, another environmental disaster was unfolding. The vast majority — between 80 and 90 percent — of rare earth elements on the market since the 1990s have come from China. One site alone, the massive Bayan Obo mine in Inner Mongolia, accounted for 45 percent of rare earth production in 2019.

      Bayan Obo spans some 4,800 hectares, about half the size of Florida’s Walt Disney World resort. It is also one of the most heavily polluted places on Earth. Clearing the land to dig for ore meant removing vegetation in an area already prone to desertification, allowing the Gobi Desert to creep southward.

      In 2010, officials in the nearby city of Baotou noted that radioactive, arsenic- and fluorine-containing mine waste, or tailings, was being dumped on farmland and into local water supplies, as well as into the nearby Yellow River. The air was polluted by fumes and toxic dust that reduced visibility. Residents complained of nausea, dizziness, migraines and arthritis. Some had skin lesions and discolored teeth, signs of prolonged exposure to arsenic; others exhibited signs of brittle bones, indications of skeletal fluorosis, Klinger says.

      The country’s rare earth industry was causing “severe damage to the ecological environment,” China’s State Council wrote in 2010. The release of heavy metals and other pollutants during mining led to “the destruction of vegetation and pollution of surface water, groundwater and farmland.” The “excessive rare earth mining,” the council wrote, led to landslides and clogged rivers.

      Faced with these mounting environmental disasters, as well as fears that it was depleting its rare earth resources too rapidly, China slashed its export of the elements in 2010 by 40 percent. The new limits sent prices soaring and kicked off concern around the globe that China had too tight of a stranglehold on these must-have elements. That, in turn, sparked investment in rare earth mining elsewhere.

      In 2010, there were few other places mining rare earths, with only minimal production from India, Brazil and Malaysia. A new mine in remote Western Australia came online in 2011, owned by mining company Lynas. The company dug into fossilized lava preserved within an ancient volcano called Mount Weld.

      Mount Weld didn’t have anywhere near the same sort of environmental impact seen in China: Its location was too remote and the mine was just a fraction of the size of Bayan Obo, according to Saleem Ali, an environmental planner at the University of Delaware. The United States, meanwhile, was eager to once again have its own source of rare earths — and Mountain Pass was still the best prospect.

      The Bayan Obo mine (shown) in China’s Inner Mongolia region was responsible for nearly half of the world’s rare earth production in 2019. Mining there has taken a heavy toll on the local residents and the environment.WU CHANGQING/VCG VIA GETTY IMAGES

      Mountain Pass mine gets revived

      After the Ivanpah Dry Lake mess, the Mountain Pass mine changed hands again. Chevron purchased it in 2005, but did not resume operations. Then, in 2008, a newly formed company called Molycorp Minerals purchased the mine with ambitious plans to create a complete rare earth supply chain in the United States.

      The goal was not just mining and processing ore, but also separating out the desirable elements and even manufacturing them into magnets. Currently, the separations and magnet manufacturing are done overseas, mostly in China. The company also proposed a plan to avoid spilling wastewater into nearby fragile habitats. Molycorp resumed mining, and introduced a “dry tailings” process — a method to squeeze 85 percent of the water out of its mine waste, forming a thick paste. The company would then store the immobilized, pasty residue in lined pits on its own land and recycle the water back into the facility.

      Unfortunately, Molycorp “was an epic debacle” from a business perspective, says Matt Sloustcher, senior vice president of communications and policy at MP Materials, current owner of Mountain Pass mine. Mismanagement ultimately led Molycorp to file for Chapter 11 bankruptcy in 2015. MP Materials bought the mine in 2017 and resumed mining later that year. By 2022, Mountain Pass mine was producing 15 percent of the world’s rare earths.

      MP Materials, too, has an ambitious agenda with plans to create a complete supply chain. And the company is determined not to repeat the mistakes of its predecessors. “We have a world-class … unbelievable deposit, an untapped potential,” says Michael Rosenthal, MP Materials’ chief operating officer. “We want to support a robust and diverse U.S. supply chain, be the magnetics champion in the U.S.”

      The challenges of separating rare earths

      On a hot morning in August, Sloustcher stands at the edge of the Mountain Pass mine, a giant hole in the ground, 800 meters across and up to 183 meters deep, big enough to be visible from space. It’s an impressive sight, and a good vantage point from which to describe a vision for the future. He points out the various buildings: where the ore is crushed and ground, where the ground rocks are chemically treated to slough off as much non–rare earth material as possible, and where the water is squeezed from that waste and the waste is placed into lined ponds.

      The end result is a highly concentrated rare earth oxide ore — still nowhere near the magnet-making stage. But the company has a three-stage plan “to restore the full rare earth supply to the United States,” from “mine to magnet,” Rosenthal says. Stage 1, begun in 2017, was to restart mining, crushing and concentrating the ore. Stage 2 will culminate in the chemical separation of the rare earth elements. And stage 3 will be magnet production, he says.

      Since coming online in 2017, MP Materials has shipped its concentrated ore to China for the next steps, including the arduous, hazardous process of separating the elements from one another. But in November, the company announced to investors that it had begun the preliminary steps for stage 2, a “major milestone” on the way to realizing its mine-to-magnet ambitions.

      With investments from the U.S. Department of Defense, the company is building two separations facilities. One plant will pull out lighter rare earth elements — those with smaller atomic numbers, including neodymium and praseodymium, both of which are key ingredients in the permanent magnets that power electric vehicles and many consumer electronics. MP Materials has additional grant money from the DOD to design and build a second processing plant to split apart the heavier rare earth elements such as dysprosium, also an ingredient in magnets, and yttrium, used to make superconductors and lasers.

      Like stage 2, stage 3 is already under way. In 2022, the company broke ground in Fort Worth, Texas, for a facility to produce neodymium magnets. And it inked a deal with General Motors to supply those magnets for electric vehicle motors.

      But separating the elements comes with its own set of environmental concerns.

      The process is difficult and leads to lots of waste. Rare earth elements are extremely similar chemically, which means they tend to stick together. Forcing them apart requires multiple sequential steps and a variety of powerful solvents to separate them one by one. Caustic sodium hydroxide causes cerium to drop out of the mix, for example. Other steps involve solutions containing organic molecules called ligands, which have a powerful thirst for metal atoms. The ligands can selectively bind to particular rare earth elements and pull them out of the mix.

      But one of the biggest issues plaguing this extraction process is its inefficiency, says Santa Jansone-Popova, an organic chemist at Oak Ridge National Laboratory in Tennessee. The scavenging of these metals is slow and imperfect, and companies have to go through a lot of extraction steps to get a sufficiently marketable amount of the elements. With the current chemical methods, “you need many, many, many stages in order to achieve the desired separation,” Jansone-Popova says. That makes the whole process “more complex, more expensive, and [it] produces more waste.”

      Under the aegis of the DOE’s Critical Materials Institute, Jansone-Popova and her colleagues have been hunting for a way to make the process more efficient, eliminating many of those steps. In 2022, the researchers identified a ligand that they say is much more efficient at snagging certain rare earths than the ligands now used in the industry. Industry partners are on board to try out the new process this year, she says.

      In addition to concerns about heavy metals and other toxic materials in the waste, there are lingering worries about the potential impacts of radioactivity on human health. The trouble is that there is still only limited epidemiological evidence of the impact of rare earth mining on human and environmental health, according to Ali, and much of that evidence is related to the toxicity of heavy metals such as arsenic. It’s also not clear, he says, how much of the concerns over radioactive waste are scientifically supported, due to the low concentration of radioactive elements in mined rare earths.

      Such concerns get international attention, however. In 2019, protests erupted in Malaysia over what activists called “a mountain of toxic waste,” about 1.5 million metric tons, produced by a rare earth separation facility near the Malaysian city of Kuantan. The facility is owned by Lynas, which ships its rare earth ore from Australia’s Mount Weld to the site. To dissolve the rare earths, the ore is cooked with sulfuric acid and then diluted with water. The residue that’s left behind can contain traces of radioactive thorium.

      Australian company Lynas built a plant near Kuantan, Malaysia, (shown in 2012) to separate and process the rare earth oxide ore mined at Mount Weld in Western Australia. Local protests erupted in 2019 over how the company disposes of its thorium-laced waste.GOH SENG CHONG/BLOOMBERG VIA GETTY IMAGES

      Lynas had no permanent storage for the waste, piling it up in hills near Kuantan instead. But the alarm over the potential radioactivity in those hills may be exaggerated, experts say. Lynas reports that workers at the site are exposed to less than 1.05 millisieverts per year, far below the radiation exposure threshold for workers of 20 millisieverts set by the International Atomic Energy Agency.

      “There’s a lot of misinformation about by­products such as thorium.… The thorium from rare earth processing is actually very low-level radiation,” Ali says. “As someone who has been a committed environmentalist, I feel right now that there’s not much science-based decision making on these things.”

      Given the concerns over new mining, environmental think tanks like the World Resources Institute have been calling for more recycling of existing rare earth materials to reduce the need for new mining and processing.

      “The path to the future has to do with getting the most out of what we take out of the ground,” says Bustamante, of the NRDC. “Ultimately the biggest lever for change is not in the mining itself, but in the manufacturing, and what we do with those materials at the end of life.”

      That means using mined resources as efficiently as possible, but also recycling rare earths out of already existing materials. Getting more out of these materials can reduce the overall environmental impacts of the mining itself, she adds.

      That is a worthwhile goal, but recycling isn’t a silver bullet, Ali says. For one thing, there aren’t enough spent rare earth–laden batteries and other materials available at the moment for recycling. “Some mining will be necessary, [because] right now we don’t have the stock.” And that supply problem, he adds, will only grow as demand increases. More

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      Extreme weather in 2022 showed the global impact of climate change

      by

      It was another shattering year.

      Climate change amped up weather extremes around the globe, smashing temperature records, sinking river levels to historic lows and raising rainfall to devastating highs. Droughts set the stage for wildfires and worsened food insecurity. Researchers found themselves pondering the limits of humans’ ability to tolerate extreme heat (SN: 7/27/22).

      The extreme events from 2022 pinpointed on the map below are just a sample of this year’s climate disasters. Each was exacerbated by human-caused climate change or is in line with projections of regional impacts.

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      In its Sixth Assessment Report, released in 2021 and 2022, the United Nations’ Intergovernmental Panel on Climate Change, or IPCC, warned that humans are dramatically overhauling Earth’s climate (SN: 8/9/21). Earth’s average surface temperature has already risen by at least 1.1 degree Celsius since preindustrial times, thanks to human inputs of heat-trapping gases to the atmosphere, particularly carbon dioxide and methane (SN: 3/10/22). That warming has shifted the flow of energy around the planet, altering weather patterns, raising sea levels and turning past extremes into new normals (SN: 2/1/22).

      And the world will have to weather more such climate extremes as carbon keeps accumulating in the atmosphere and global temperatures continue to rise. But IPCC scientists and others hope that, by highlighting the regional and local effects of climate change, the world will ramp up its efforts to reduce climate-warming emissions — averting a more disastrous future. More