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    These six foods may become more popular as the planet warms

    No matter how you slice it, climate change will alter what we eat in the future. Today, just 13 crops provide 80 percent of people’s energy intake worldwide, and about half of our calories come from wheat, maize and rice. Yet some of these crops may not grow well in the higher temperatures, unpredictable rainfall and extreme weather events caused by climate change. Already, drought, heat waves and flash floods are damaging crops around the world.

    “We must diversify our food basket,” says Festo Massawe. He’s executive director of Future Food Beacon Malaysia, a group at the University of Nottingham Malaysia campus in Semenyih that studies the impact of climate change on food security.

    That goes beyond what we eat to how we grow it. The trick will be investing in every possible solution: breeding crops so they’re more climate resilient, genetically engineering foods in the lab and studying crops that we just don’t know enough about, says ecologist Samuel Pironon of the Royal Botanic Gardens, Kew in London. To feed a growing population in a rapidly changing world, food scientists are exploring many possible avenues, while thinking about how to be environmentally friendly.

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    Consumer preferences are part of the equation as well. “It does have to be that right combination of: It looks good, it tastes good and it’s the right price point,” says Halley Froehlich, an aquaculture and fisheries scientist at the University of California, Santa Barbara.

    Here are six foods that could check all those boxes and feature more prominently on menus and grocery shelves in the future.

    1. Millet

    SZJPHOTO/MOMENT/GETTY IMAGES

    Source of: Carbohydrates, protein, minerals (potassium, phosphorus and magnesium)Uses: Whole grain; gluten-free flour, pasta, chips, beer

    The United Nations has declared 2023 the International Year of Millets (a handful of varieties exist). Quinoa earned the same honor in 2013, and its sales skyrocketed. First cultivated in Asia some 10,000 years ago, millet is a staple grain in parts of Asia and Africa. Compared with wheat, maize and rice, millet is much more climate resilient; the crop needs little water and thrives in warmer, drier environments. Some more good news: Millet is one of many ancient grains — including teff, amaranth and sorghum — that are similarly sustainable and resilient (not to mention capable of being turned into beer).

    2. Bambara groundnut

    PONSULAK/ISTOCK/GETTY IMAGES PLUS

    Source of: Protein, fiber, minerals (potassium, magnesium and iron)Uses: Roasted or boiled; gluten-free flour; dairy-free milk

    You’ve heard of almond milk and soy milk. The next alternative at your coffee shop could be made from Bambara groundnuts, a drought-tolerant legume native to sub-Saharan Africa. Like other legumes, the Bambara groundnut is packed with protein. And bacteria on the plant convert atmospheric nitrogen into ammonia so the groundnut grows well in nutrient-poor soil without chemical fertilizers. A better understanding of the plant, says Festo Massawe of Future Food Beacon Malaysia, could pave the way for breeding programs to help the Bambara groundnut become as popular as the soybean, a legume that produces high yields but is less drought tolerant.

    3. Mussels

    MATT MACRO/EYEEM/GETTY IMAGES

    Source of: Protein, omega-3, vitamin B12, minerals (iron, manganese and zinc)Uses: Steamed; added to pasta dishes, stews, soups

    A delicious mussel linguine might someday become a weeknight regular on the family menu. Mussels and other bivalves, including oysters, clams and scallops, could make up about 40 percent of seafood by 2050, according to a 2020 report in Nature. With no need to be watered or fertilized, bivalve farms are prime for scaling up, which would lower prices for consumers. All bivalves have merit, but Halley Froehlich of UC Santa Barbara singles out mussels as “super hardy,” “super nutritious” and underhyped. One downside: Shell-forming creatures are threatened as rising carbon levels boost ocean acidification. Kelp might be able to help.

    4. Kelp

    MOAIMAGE/MOMENT/GETTY IMAGES

    Source of: Vitamins, minerals (iodine, calcium and iron), antioxidantsUses: Salads, smoothies, salsa, pickles, noodles and chips; also found in toothpaste, shampoo and biofuels

    Kelp has a few cool climate-friendly tricks. For one, by taking in carbon dioxide during photosynthesis, it can lower the acidity of its watery surroundings. Farmers in Maine and Alaska grow kelp and bivalves together so that the shelled critters can benefit from the less acidic water. Kelp also sequesters carbon, like underwater trees. That means growing and eating more kelp could be good for the environment. While kelp and other seaweeds have been widely consumed in Asia for thousands of years, they’re still an acquired taste in many Western countries.

    5. Enset

    MIKE GOLDWATER/ALAMY STOCK PHOTO

    Source of: Carbohydrates, calcium, potassium and zincUses: Porridge or bread; also used to make rope, plates and building materials

    The drought-tolerant enset, cultivated in Ethiopia, is nicknamed the “false banana” because the plant resembles a banana tree, though its fruit is inedible. It’s also called “the tree against hunger” because its starchy stems can be harvested at any time of year, making it a reliable buffer food crop during dry periods. A 2021 report in Environmental Research Letters suggests that the enset’s range could be expanded to other parts of Africa, and possibly beyond. The processing required to make enset edible is complex, says study author James Borrell of the Royal Botanic Gardens, Kew. So any expansion would have to be led by the communities who hold that Indigenous knowledge.

    6. Cassava

    ILTONROGERIO/ISTOCK/GETTY IMAGES PLUS

    Source of: Carbohydrates, potassium, vitamin CUses: Whole cooked root; gluten-free flour; tapioca pearls in bubble tea

    Cassava, a starchy root vegetable from South America, checks the boxes for climate resilience, sustainability and nutrition. Now grown in over 100 countries, cassava can withstand temperatures of up to 40° Celsius and is salt and drought tolerant. An added plus: Higher atmospheric CO2 levels enhance the plant’s tolerance to stress and can lead to higher yields. Raw cassava can contain toxic levels of cyanide, but the chemical can be removed by peeling, soaking and cooking the root. More

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    Replacing some meat with microbial protein could help fight climate change

    “Fungi Fridays” could save a lot of trees — and take a bite out of greenhouse gas emissions. Eating one-fifth less red meat and instead munching on microbial proteins derived from fungi or algae could cut annual deforestation in half by 2050, researchers report May 5 in Nature.

    Raising cattle and other ruminants contributes methane and nitrous oxide to the atmosphere, while clearing forests for pasture lands adds carbon dioxide (SN: 4/4/22; SN: 7/13/21). So the hunt is on for environmentally friendly substitutes, such as lab-grown hamburgers and cricket farming (SN: 9/20/18; SN: 5/2/19).

    Another alternative is microbial protein, made from cells cultivated in a laboratory and nurtured with glucose. Fermented fungal spores, for example, produce a dense, doughy substance called mycoprotein, while fermented algae produce spirulina, a dietary supplement.

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    Cell-cultured foods do require sugar from croplands, but studies show that mycoprotein produces fewer greenhouse gas emissions and uses less land and water than raising cattle, says Florian Humpenöder, a climate modeler at Potsdam Institute for Climate Impact Research in Germany. However, a full comparison of foods’ future environmental impacts also requires accounting for changes in population, lifestyle, dietary patterns and technology, he says.

    So Humpenöder and colleagues incorporated projected socioeconomic changes into computer simulations of land use and deforestation from 2020 through 2050. Then they simulated four scenarios, substituting microbial protein for 0 percent, 20 percent, 50 percent or 80 percent of the global red meat diet by 2050.

    A little substitution went a long way, the team found: Just 20 percent microbial protein substitution cut annual deforestation rates — and associated CO2 emissions — by 56 percent from 2020 to 2050.

    Eating more microbial proteins could be part of a portfolio of strategies to address the climate and biodiversity crises — alongside measures to protect forests and decarbonize electricity generation, Humpenöder says. More

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    How some sunscreens damage coral reefs

    One common chemical in sunscreen can have devastating effects on coral reefs. Now, scientists know why.

    Sea anemones, which are closely related to corals, and mushroom coral can turn oxybenzone — a chemical that protects people against ultraviolet light — into a deadly toxin that’s activated by light. The good news is that algae living alongside the creatures can soak up the toxin and blunt its damage, researchers report in the May 6 Science.

    But that also means that bleached coral reefs lacking algae may be more vulnerable to death. Heat-stressed corals and anemones can eject helpful algae that provide oxygen and remove waste products, which turns reefs white. Such bleaching is becoming more common as a result of climate change (SN: 4/7/20).

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    The findings hint that sunscreen pollution and climate change combined could be a greater threat to coral reefs and other marine habitats than either would be separately, says Craig Downs. He is a forensic ecotoxicologist with the nonprofit Haereticus Environmental Laboratory in Amherst, Va., and was not involved with the study.

    Previous work suggested that oxybenzone can kill young corals or prevent adult corals from recovering after tissue damage. As a result, some places, including Hawaii and Thailand, have banned oxybenzone-containing sunscreens.

    In the new study, environmental chemist Djordje Vuckovic of Stanford University and colleagues found that glass anemones (Exaiptasia pallida) exposed to oxybenzone and UV light add sugars to the chemical. While such sugary add-ons would typically help organisms detoxify chemicals and clear them from the body, the oxybenzone-sugar compound instead becomes a toxin that’s activated by light.

    Anemones exposed to either simulated sunlight or oxybenzone alone survived the length of the experiment, or 21 days, the team showed. But all anemones exposed to fake sunlight while submersed in water containing the chemical died within 17 days.

    Algae can soak up oxybenzone and its toxic by-products, a study shows. Sea anemones lacking algae (white) died sooner than animals with algae (brown) when exposed to oxybenzone and UV light.Djordje Vuckovic and Christian Renicke

    The anemones’ algal friends absorbed much of the oxybenzone and the toxin that the animals were exposed to in the lab. Anemones lacking algae died days sooner than anemones with algae.

    In similar experiments, algae living inside mushroom coral (Discosoma sp.) also soaked up the toxin, a sign that algal relationships are a safeguard against its harmful effects. The coral’s algae seem to be particularly protective: Over eight days, no mushroom corals died after being exposed to oxybenzone and simulated sunlight.

    It’s still unclear what amount of oxybenzone might be toxic to coral reefs in the wild. Another lingering question, Downs says, is whether other sunscreen components that are similar in structure to oxybenzone might have the same effects. Pinning that down could help researchers make better, reef-safe sunscreens.   More

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    How much does eating meat affect nations’ greenhouse gas emissions?

    The food we eat is responsible for an astounding one-third of global greenhouse gas emissions caused by human activities, according to two comprehensive studies published in 2021.

    “When people talk about food systems, they always think about the cow in the field,” says statistician Francesco Tubiello, lead author of one of the reports, appearing in last June’s Environmental Research Letters. True, cows are a major source of methane, which, like other greenhouse gases, traps heat in the atmosphere. But methane, carbon dioxide and other planet-warming gases are released from several other sources along the food production chain.

    Before 2021, scientists like Tubiello, of the Food and Agriculture Organization of the United Nations, were well aware that agriculture and related land use changes made up roughly 20 percent of the planet’s greenhouse gas emissions. Such land use changes include cutting down forests to make way for cattle grazing and pumping groundwater to flood fields for the sake of agriculture.

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    But new modeling techniques used by Tubiello and colleagues, plus a study from a group at the European Commission Tubiello worked with, brought to light another big driver of emissions: the food supply chain. All the steps that take food from the farm to our plates to the landfill — transportation, processing, cooking and food waste — bring food-related emissions up from 20 percent to 33 percent.

    To slow climate change, the foods we eat deserve major attention, just like fossil fuel burning, says Amos Tai, an environmental scientist at the Chinese University of Hong Kong. The fuller picture of food-related emissions demonstrates that the world needs to make drastic changes to the food system if we are to reach international goals for reducing global warming.

    Change from developing countries

    Scientists have gained a clearer understanding of global human-related emissions in recent years through databases like EDGAR, or Emissions Database for Global Atmospheric Research, developed by the European Union. The database covers every country’s human-emitting activities, from energy production to landfill waste, from 1970 to the present. EDGAR uses a unified methodology to calculate emissions for all economic sectors, says Monica Crippa, a scientific officer at the European Commission’s Joint Research Centre.

    Crippa and colleagues, with help from Tubiello, built a companion database of food system–related emissions called EDGAR-FOOD. Using that database, the researchers arrived at the same one-third estimate as Tubiello’s group.

    Crippa’s team’s calculations, reported in Nature Food in March 2021, split food system emissions into four broad categories: land (including both agriculture and related land use changes), energy (used for producing, processing, packaging and transporting goods), industry (including the production of chemicals used in farming and materials used to package food) and waste (from unused food).

    The land sector is the biggest culprit in food system emissions, Crippa says, accounting for about 70 percent of the global total. But the picture looks different across different nations. The United States and other developed countries rely on highly centralized megafarms for much of their food production; so the energy, industry and waste categories make up more than half of these countries’ food system emissions.

    In developing countries, agriculture and changing land use are far greater contributors. Emissions in historically less developed countries have also been rising in the last 30 years, as these countries have cut down wild areas to make way for industrial farming and started eating more meat, another major contributor to emissions with impacts across all four categories.

    As a result, agriculture and related landscape shifts have driven major increases in food system emissions among developing countries in recent decades, while emissions in developed countries have not grown.

    For instance, China’s food emissions shot up by almost 50 percent from 1990 to 2018, largely due to a rise in meat-eating, according to the EDGAR-FOOD database. In 1980, the average Chinese person ate about 30 grams of meat a day, Tai says. In 2010, the average person in China ate almost five times as much, or just under 150 grams of meat a day.

    Top-emitting economies

    In recent years, Crippa says, six economies, the top emitters, have been responsible for more than half of total global food emissions. These economies, in order, are China, Brazil, the United States, India, Indonesia and the European Union. The immense populations of China and India help drive their high numbers. Brazil and Indonesia make the list because large swaths of their rainforests have been cut down to make room for farming. When those trees come down, vast amounts of carbon flow into the atmosphere (SN: 7/3/21 & 7/17/21, p. 24).

    The United States and the European Union are on the list because of heavy meat consumption. In the United States, meat and other animal products contribute the vast majority of food-related emissions, says Richard Waite, a researcher at the World Resources Institute’s food program in Washington, D.C.

    Waste is also a huge issue in the United States: More than one-third of food produced never actually gets eaten, according to a 2021 report from the U.S. Environmental Protection Agency. When food goes uneaten, the resources used to produce, transport and package it are wasted. Plus, the uneaten food goes into landfills, which produce methane, carbon dioxide and other gases as the food decomposes.

    Meat consumption drives emissions

    Climate advocates who want to reduce food emissions often focus on meat consumption, as animal products lead to far greater emissions than plants. Animal production uses more land than plant production, and “meat production is heavily inefficient,” Tai says.

    “If we eat 100 calories of grain, like maize or soybeans, we get that 100 calories,” he explains. All the energy from the food is delivered directly to the person who eats it. But if the 100 calories’ worth of grain is instead fed to a cow or a pig, when the animal is killed and processed for food, just one-tenth of the energy from that 100 calories of grain goes to the person eating the animal.

    Methane production from “the cow in the field” is another factor in meat consumption: Cows release this gas via their manure, burps and flatulence. Methane traps more heat per ton emitted than carbon dioxide, Tubiello says. So emissions from cattle farms can have an outsize impact (SN: 11/28/15, p. 22). These livestock emissions account for about one-third of global methane emissions, according to a 2021 U.N. report.

    Shifting from meats to plants

    U.S. residents should consider how they can shift to what Brent Kim calls “plant-forward” diets. “Plant-forward doesn’t mean vegan. It means reducing animal product intake, and increasing the share of plant foods that are on the plate,” says Kim, program officer at the Johns Hopkins Center for a Livable Future.

    Kim and colleagues estimated food emissions by diet and food group for 140 countries and territories, using a similar modeling framework to EDGAR-FOOD. However, the framework includes only the food production emissions (i.e. agriculture and land use), not processing, transportation and other pieces of the food system incorporated in EDGAR-FOOD.

    Producing the average U.S. resident’s diet generates more than 2,000 kilograms of greenhouse gas emissions per year, the researchers reported in 2020 in Global Environmental Change. The group measured emissions in terms of “CO2 equivalents,” a standardized unit allowing for direct comparisons between CO2 and other greenhouse gases like methane.

    Going meatless one day a week brings down that figure to about 1,600 kilograms of CO2 equivalents per year, per person. Going vegan — a diet without any meat, dairy or other animal products — cuts it by 87 percent to under 300. Going even two-thirds vegan offers a sizable drop to 740 kilograms of CO2 equivalents.

    Kim’s modeling also offers a “low food chain” option, which brings emissions down to about 300 kilograms of CO2 equivalents per year, per person. Eating low on the food chain combines a mostly plant-based diet with animal products that come from more climate-friendly sources that do not disturb ecological systems. Examples include insects, smaller fish like sardines, and oysters and other mollusks.

    Tai agrees that not everybody needs to become a vegetarian or vegan to save the planet, as meat can have important cultural and nutritional value. If you want to “start from the biggest polluter,” he says, focus on cutting beef consumption.

    But enough people need to make these changes to “send a signal back to the market” that consumers want more plant-based options, Tubiello says. Policy makers at the federal, state and local levels can also encourage climate-friendly farming practices, reduce food waste in government operations and take other actions to cut down the resources used in food production, Waite says.

    For example, the World Resources Institute, where Waite works, is part of an initiative called the Cool Food Pledge, in which companies, universities and city governments have signed on to reduce the climate impacts of the food they serve. The institutions agree to track the food they purchase every year to ensure they are progressing toward their goals, Waite says.

    Developed countries like the United States — which have been heavy meat consumers for decades — can have a big impact by changing food choices. Indeed, a paper published in Nature Food in January shows that if the populations of 54 high-income nations switched to a plant-focused diet, annual emissions from these countries’ agricultural production could drop by more than 60 percent. More

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    Coastal cities around the globe are sinking

    Coastal cities around the globe are sinking by up to several centimeters per year, on average, satellite observations reveal. The one-two punch of subsiding land and rising seas means that these coastal regions are at greater risk for flooding than previously thought, researchers report in the April 16 Geophysical Research Letters.

    Matt Wei, an earth scientist at the University of Rhode Island in Narragansett, and colleagues studied 99 coastal cities on six continents. “We tried to balance population and geographic location,” he says. While subsidence has been measured in cities previously, earlier research has tended to focus on just one city or region. This investigation is different, Wei says. “It’s one of the first to really use data with global coverage.”

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    Wei and his team relied on observations made from 2015 to 2020 by a pair of European satellites. Instruments onboard beam microwave signals toward Earth and then record the waves that bounce back. By measuring the timing and intensity of those reflected waves, the team determined the height of the ground with millimeter accuracy. And because each satellite flies over the same part of the planet every 12 days, the researchers were able to trace how the ground deformed over time.

    The largest subsidence rates — up to five centimeters per year —are mostly in Asian cities like Tianjin, China; Karachi, Pakistan; and Manila, Philippines, the team found. What’s more, one-third, or 33, of the analyzed cities are sinking in some places by more than a centimeter per year.

    That’s a worrying trend, says Darío Solano-Rojas, an earth scientist at the National Autonomous University of Mexico in Mexico City who was not involved in the research. These cities are being hit with a double whammy: At the same time that sea levels are rising due to climate change, the land is sinking (SN: 8/15/18). “Understanding that part of the problem is a big deal,” Solano-Rojas says.

    Wei and his colleagues think that the subsidence is largely caused by people. When the researchers looked at Google Earth imagery of the regions within cities that were rapidly sinking, the team saw mostly residential or commercial areas. That’s a tip-off that the culprit is groundwater extraction, the team concluded. Landscapes tend to settle as water is pumped out of aquifers (SN: 10/22/12).

    But there’s reason to be hopeful. In the past, cities such as Shanghai and Indonesia’s Jakarta were sinking by more than 10 centimeters per year, on average. But now subsidence in those places has slowed, possibly due to recent governmental regulations limiting groundwater extraction. More

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    More than 57 billion tons of soil have eroded in the U.S. Midwest

    With soils rich for cultivation, most land in the Midwestern United States has been converted from tallgrass prairie to agricultural fields. Less than 0.1 percent of the original prairie remains.

    This shift over the last 160 years has resulted in staggering — and unsustainable — soil erosion rates for the region, researchers report in the March Earth’s Future. The erosion is estimated to be double the rate that the U.S. Department of Agriculture says is sustainable. If it continues unabated, it could significantly limit future crop production, the scientists say.

    In the new study, the team focused on erosional escarpments — tiny cliffs formed through erosion — lying at boundaries between prairie and agricultural fields (SN: 1/20/96). “These rare prairie remnants that are scattered across the Midwest are sort of a preservation of the pre-European-American settlement land surface,” says Isaac Larsen, a geologist at the University of Massachusetts Amherst.

    At 20 sites in nine Midwestern states, with most sites located in Iowa, Larsen and colleagues used a specialized GPS system to survey the altitude of the prairie and farm fields. That GPS system “tells you where you are within about a centimeter on Earth’s surface,” Larsen says. This enables the researchers to detect even small differences between the height of the prairie and the farmland.

    At each site, the researchers took these measurements at 10 or more spots. The team then measured erosion by comparing the elevation differences of the farmed and prairie land. The researchers found that the agricultural fields were 0.37 meters below the prairie areas, on average.

    Geologist Isaac Larsen stands at an erosional escarpment, a meeting point of farmland and prairie, in Stinson Prairie, Iowa. Studying these escarpments shows there’s been a startling amount of erosion in the U.S. Midwest since farming started there more than 150 years ago.University of Massachusetts Amherst

    This corresponds to the loss of roughly 1.9 millimeters of soil per year from agricultural fields since the estimated start of traditional farming at these sites more than a century and a half ago, the researchers calculate. That rate is nearly double the maximum of one millimeter per year that the USDA considers sustainable for these locations.  

    There are two main ways that the USDA currently estimates the erosion rate in the region. One way estimates the rate to be about one-third of that reported by the researchers. The other estimates the rate to be just one-eighth of the researchers’ rate. Those USDA estimates do not include tillage, a conventional farming process in which machinery is used to turn the soil and prepare it for planting. By disrupting the soil structure, tilling increases surface runoff and erosion due to soil moving downslope.

    Larsen and colleagues say that they would like to see tillage incorporated into the USDA’s erosion estimates. Then, the USDA numbers might better align with the whopping 57.6 billion metric tons of soil that the researchers estimate has been lost across the entire region in the last 160 years.

    This massive “soil loss is already causing food production to decline,” Larsen says. As soil thickness decreases, the amount of corn successfully grown in Iowa is reduced, research shows. And disruption to the food supply could continue or worsen if the estimated rate of erosion persists.

    Not everyone is convinced that the average amount of soil lost each year has remained steady since farming in the region started. Much of the erosion that the researchers measured could have been caused in the earlier histories of these sites, dating back to when farmers “began to break prairies and/or forests and clear things,” says agronomist Michael Kucera.

    Perhaps current erosion rates have slowed, says Kucera, who is the steward of the National Erosion Database at the USDA’s National Soil Survey Center in Lincoln, Neb.

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    To help reduce future erosion, farmers can use no-till farming and plant cover crops, the researchers note. By planting cover crops during off-seasons, farmers reduce the amount of time the soil is bare, making it less vulnerable to wind and water erosion.

    In the United States, no-till and similar practices to help limit erosion have been implemented at least sometimes by 51 percent of corn, cotton, soybean and wheat farmers, according to the USDA. But cover crops are only used in about 5 percent of cases where they could be, says Bruno Basso, a sustainable agriculture researcher at Michigan State University in East Lansing who wasn’t involved with the study. “It costs $40 to $50 per acre to plant a cover crop,” he says. Though some government grant funding is available, “the costs of cover crops are not supported,” and there is a need for additional incentives, he says.

    To implement no-till strategies, “the farmer has to be a better manager,” says Keith Berns, a farmer who co-owns and operates Green Cover Seed, which is headquartered in Bladen, Neb. His company provides cover crop seeds and custom seed mixtures. He has also been using no-till practices for decades.

    To succeed, farmers must decide what particular cover crops are most suitable for their land, when to grow them and when to kill them. Following these regimens, which can be more complicated than traditional farming, can be “difficult to do on large scales,” Berns says.

    Cover crops can confer benefits such as helping farmers repair erosion and control weeds within the first year of planting. But it can take multiple years for the crops’ financial benefits to exceed their cost. Some farmers don’t even own the land they work, making it even less lucrative for them to invest in cover crops, Berns notes. 

    Building soil health can take half a decade, Basso says. “Agriculture is really always facing this dilemma [of] short-sighted, economically driven decisions versus longer-term sustainability of the whole enterprise.” More

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    Climate change intensified deadly storms in Africa in early 2022

    Climate change amped up the rains that pounded southeastern Africa and killed hundreds of people during two powerful storms in early 2022.

    But a dearth of regional data made it difficult to pinpoint just how large of a role climate change played, scientists said April 11 at a news conference.

    The findings were described in a study, published online April 11, by a consortium of climate scientists and disaster experts called the World Weather Attribution network.

    A series of tropical storms and heavy rain events battered southeast Africa in quick succession from January through March. For this study, the researchers focused on two events: Tropical Storm Ana, which led to flooding in northern Madagascar, Malawi and Mozambique in January and killed at least 70 people; and Cyclone Batsirai, which inundated southern Madagascar in February and caused hundreds more deaths.

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    To search for the fingerprints of climate change, the team first selected a three-day period of heavy rain for each storm. Then the researchers tried to amass observational data from the region to reconstruct historical daily rainfall records from 1981 to 2022.

    Only four weather stations, all in Mozambique, had consistent, high-quality data spanning those decades. But, using the data on hand, the team was able to construct simulations for the region that represented climate with and without human-caused greenhouse gas emissions.

    The aggregate of those simulations revealed that climate change did play a role in intensifying the rains, Izidine Pinto, a climatologist at the University of Cape Town in South Africa, said at the news event. But with insufficient historical rainfall data, the team “could not quantify the precise contribution” of climate change, Pinto said.

    The study highlights how information on extreme weather events “is very much biased toward the Global North … [whereas] there are big gaps in the Global South,” said climate scientist Friedericke Otto of Imperial College London.

    That’s an issue also highlighted by the Intergovernmental Panel on Climate Change. The IPCC cites insufficient Southern Hemisphere data as a barrier to assessing the likelihood of increasing frequency and intensity of tropical cyclones beyond the North Atlantic Ocean (SN: 8/9/21). More

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    50 years ago, the future of solar energy looked bright

    Farming the sun’s energy – Science News, April 8, 1972

    More and more scientists and engineers are beginning to believe that solar conversion will account for a significant portion of the world’s future power needs.… What has changed the atmosphere lately is … the possibility of putting together large-scale units, solar-energy “farms” that would compete with power stations in the megawatt range and higher.

    Update

    Solar energy production in the United States ramped up as solar panels became cheaper to manufacture and more efficient at generating electricity (SN: 3/1/08, p. 133). Since the first U.S. solar power plant opened in 1982, thousands more have been built, bringing the country’s solar capacity today to more than 100 gigawatts. In 2021, solar energy made up nearly 3 percent of the electricity produced in the United States. And the future is looking bright: Solar energy and storage is projected to account for more than 60 percent of the U.S. power grid’s new generating capacity from 2022 through 2023, according to the U.S. Energy Information Administration. More