Heart

Winds howl at over 300 kilometers per hour, battering at a two-story wooden house and ripping its roof from its walls. Then comes the water. A 6-meter-tall wave engulfs the structure, knocking the house off its foundation and washing it away.

That’s the terrifying vision of researchers planning a new state-of-the-art facility to re-create the havoc wreaked by the most powerful hurricanes on Earth. In January, the National Science Foundation awarded a $12.8 million grant to researchers to design a facility that can simulate wind speeds of at least 290 km/h — and can, at the same time, produce deadly, towering storm surges.

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No facility exists that can produce such a one-two punch of extreme wind and water. But it’s an idea whose time has come — and not a moment too soon.

“It’s a race against time,” says disaster researcher Richard Olson, director of extreme events research at Florida International University, or FIU, in Miami.

Hurricanes are being made worse by human-caused climate change: They’re getting bigger, wetter, stronger and slower (SN: 9/13/18; SN: 11/11/20). Scientists project that the 2022 Atlantic Ocean hurricane season, spanning June 1 to November 30, will be the seventh straight season with more storms than average. Recent seasons have been marked by an increase in rapidly intensifying hurricanes linked to warming ocean waters (SN: 12/21/20).

Those trends are expected to continue as the Earth heats up further, researchers say. And coastal communities around the world need to know how to prepare: how to build structures — buildings, bridges, roads, water and energy systems — that are resilient to such punishing winds and waves.

To help with those preparations, FIU researchers are leading a team of wind and structural engineers, coastal and ocean engineers, computational modelers and resilience experts from around the United States to work out how best to simulate these behemoths. Combining extreme wind and water surges into one facility is uncharted territory, says Ioannis Zisis, a wind engineer at FIU. “There is a need to push the envelope,” Zisis says. But as for how exactly to do it, “the answer is simple: We don’t know. That’s what we want to find out.”

Prepping for “Category 6”

It’s not that such extreme storms haven’t been seen on Earth. Just in the last few years, Hurricanes Dorian (2019) and Irma (2017) in the Atlantic Ocean and super Typhoon Haiyan (2013) in the Pacific Ocean have brought storms with wind speeds well over 290 km/h. Such ultraintense storms are sometimes referred to as “category 6” hurricanes, though that’s not an official designation.

The National Oceanic and Atmospheric Administration, or NOAA, rates hurricanes in the Atlantic and eastern Pacific oceans on a scale of 1 to 5, based on their wind speeds and how much damage those winds might do. Each category spans an increment of roughly 30 km/h.  

Category 1 hurricanes, with wind speeds of 119 to 153 km/h, produce “some damage,” bringing down some power lines, toppling trees and perhaps knocking roof shingles or vinyl siding off a house. Category 5 storms, with winds starting at 252 km/h, cause “catastrophic damage,” bulldozing buildings and potentially leaving neighborhoods uninhabitable for weeks to months.

But 5 is as high as it gets on the official scale; after all, what could be more devastating than catastrophic damage? That means that even monster storms like 2019’s Hurricane Dorian, which flattened the Bahamas with wind speeds of up to nearly 300 km/h, are still considered category 5 (SN: 9/3/19).

“Strictly speaking, I understand that [NOAA doesn’t] see the need for a category 6,” Olson says. But there is a difference in public perception, he says. “I see it as a different type of storm, a storm that is simply scarier.”

And labels aside, the need to prepare for these stronger storms is clear, Olson says. “I don’t think anybody wants to be explaining 20 years from now why we didn’t do this,” he says. “We have challenged nature. Welcome to payback.”

Superstorm simulation

FIU already hosts the Wall of Wind, a huge hurricane simulator housed in a large hangar anchored at one end by an arc of 12 massive yellow fans. Even at low wind speeds — say, around 50 km/h — the fans generate a loud, unsettling hum. At full blast, those fans can generate wind speeds of up to 252 km/h — equivalent to a low-grade category 5 hurricane.

Inside, researchers populate the hangar with structures mimicking skyscrapers, houses and trees, or shapes representing the bumps and dips of the ground surface. Engineers from around the world visit the facility to test out the wind resistance of their own creations, watching as the winds pummel at their structural designs.

Twelve fans tower over one end of the Wall of Wind, a large experimental facility at Florida International University in Miami. There, winds as fast as 252 kilometers per hour let researchers re-create conditions experienced during a low-grade category 5 hurricane.NSF-NHERI Wall of Wind/FIU

It’s one of eight facilities in a national network of laboratories that study the potential impacts of wind, water and earthquake hazards, collectively called the U.S. Natural Hazards Engineering Research Infrastructure, or NHERI.

The Wall of Wind is designed for full-scale wind testing of entire structures. Another wind machine, hosted at the University of Florida in Gainesville, can zoom in on the turbulent behavior of winds right at the boundary between the atmosphere and ground. Then there are the giant tsunami- and storm surge–simulating water wave tanks at Oregon State University in Corvallis.

The new facility aims to build on the shoulders of these giants, as well as on other experimental labs around the country. The design phase is projected to take four years, as the team ponders how to ramp up wind speeds — possibly with more, or more powerful fans than the Wall of Wind’s — and how to combine those gale-force winds and massive water tanks in one experimental space.

Existing labs that study wind and waves together, albeit on a much smaller scale, can offer some insight into that aspect of the design, says Forrest Masters, a wind engineer at the University of Florida and the head of that institution’s NHERI facility.

This design phase will also include building a scaled-down version of the future lab as proof of concept. Building the full-scale facility will require a new round of funding and several more years.

Past approaches to studying the impacts of strong wind storms tend to use one of three approaches: making field observations of the aftermath of a given storm; building experimental facilities to re-create storms; and using computational simulations to visualize how those impacts might play out over large geographical regions. Each of these approaches has strengths and limitations, says Tracy Kijewski-Correa, a disaster risk engineer at the University of Notre Dame in Indiana.

“In this facility, we want to bring together all of these methodologies,” to get as close as possible to recreating what Mother Nature can do, Kijewski-Correa says.  

It’s a challenging engineering problem, but an exciting one. “There’s a lot of enthusiasm for this in the broader scientific community,” Masters says. “If it gets built, nothing like it will exist.” More

In 2007, 22-year-old P. Ramesh’s groundnut farm was losing money. As was the norm in most of India (and still is), Ramesh was using a cocktail of pesticides and fertilizers across his 2.4 hectares in the Anantapur district of southern India. In this desert-like area, which gets less than 600 millimeters of rainfall most years, farming is a challenge.

“I lost a lot of money growing groundnuts through chemical farming methods,” says Ramesh, who goes by the first letter of his father’s name followed by his first name, as is common in many parts of southern India. The chemicals were expensive and his yields low.

Then in 2017, he dropped the chemicals. “Ever since I took up regenerative agricultural practices like agroforestry and natural farming, both my yield and income have increased,” he says.

Agroforestry involves planting woody perennials (trees, shrubs, palms, bamboos, etc.) alongside agricultural crops (SN: 7/3/21 & 7/17/21, p. 30). One natural farming method calls for replacing all chemical fertilizers and pesticides with organic matter such as cow dung, cow urine and jaggery, a type of solid dark sugar made from sugarcane, to boost soil nutrient levels. Ramesh also expanded his crops, originally groundnuts and some tomatoes, by adding papaya, millets, okra, eggplant (called brinjal locally) and other crops.

Farmers in Anantapur, India, pose with the natural fertilizer they use on their crops. Called Ghanajeevamritam, it contains jaggery, cow dung, cow urine and sometimes flour from dried beans. M. Shaikshavali

With help from the nonprofit Accion Fraterna Ecology Centre in Anantapur, which works with farmers who want to try sustainable farming, Ramesh increased his profits enough to buy more land, expanding his parcel to about four hectares. Like the thousands of other farmers practicing regenerative farming across India, Ramesh has managed to nourish his depleted soil, while his new trees help keep carbon out of the atmosphere, thus playing a small but important role in reducing India’s carbon footprint. Recent studies have shown that the carbon sequestration potential of agroforestry is as much as 34 percent higher than standard forms of agriculture.

In western India, more than 1,000 kilometers from Anantapur, in Dhundi village in Gujarat, 36-year-old Pravinbhai Parmar is using his rice farm for climate change mitigation. By installing solar panels, he no longer uses diesel to power his groundwater pumps. And he has an incentive to pump only the water he needs because he can sell the electricity he doesn’t use.

If all farmers like Parmar shifted to solar, India’s carbon emissions, which are 2.88 billion metric tons per year, could drop by between 45 million and 62 million tons annually, according to a 2020 report in Carbon Management. So far, the country has about 250,000 solar irrigation pumps out of an estimated 20 million to 25 million total groundwater pumps.

For a nation that has to provide for what will soon be the world’s largest population, growing food while trying to bring down already high greenhouse gas emissions from agricultural practices is difficult. Today, agriculture and livestock account for 14 percent of India’s gross national greenhouse gas emissions. Adding in the electricity used by the agriculture sector brings this figure up to 22 percent.

Ramesh and Parmar are part of a small but growing group of farmers getting assistance from government and nongovernmental programs to change how they farm. There’s still a ways to go to reach the estimated 146 million others who cultivate 160 million hectares of arable land in India. But these farmers’ success stories are testimony that one of India’s largest emitting sectors can change.

Pravinbhai Parmar (center) poses with fellow farmers who are part of the solar irrigation program in Dhundi village, Gujarat.IWMI-TATA Program, Shashwat Cleantech and Dhundi Saur Urja Utpadak Sahkari Mandali

Feeding the soil, sustaining farmers

India’s farmers are already deeply feeling the effects of climate change, coping with dry spells, erratic rainfall and increasingly frequent heat waves and tropical cyclones. “When we talk about climate-smart agriculture, we are largely talking about how it has reduced emissions,” says Indu Murthy, sector head for climate, environment and sustainability at the Center for Study of Science, Technology and Policy, a think tank in Bengaluru. But such a system should also help farmers “cope with unexpected changes and weather patterns,” she says.

This, in many ways, is the philosophy driving a variety of sustainable and regenerative agricultural practices under the agroecology umbrella. Natural farming and agroforestry are two components of this system that are finding more and more takers across India’s varied landscapes, says Y.V. Malla Reddy, director of Accion Fraterna Ecology Centre.

“For me, the important change is the change in attitude of people towards trees and vegetation in the last few decades,” Reddy says. “In the ’70s and ’80s, people were not really conscious of the value of the trees, but now they consider trees, especially fruit and utilitarian trees, as also a source of income.” Reddy has advocated for sustainable farming in India for close to 50 years. Certain types of trees, such as pongamia, subabul and avisa, have economic benefits apart from their fruits; they provide fodder for livestock and biomass for fuel.

Reddy’s organization has provided assistance to more than 60,000 Indian farming families to practice natural farming and agroforestry on almost 165,000 hectares. Calculation of the soil carbon sequestration potential of their work is ongoing. But a 2020 report by India’s Ministry of Environment, Forest and Climate Change notes that these farming practices can help India reach its goal of having 33 percent forest and tree cover to meet its carbon sequestration commitments under the Paris climate agreement by 2030.

Regenerative agriculture is a relatively inexpensive way to reduce carbon dioxide in the atmosphere, as compared with other solutions. Regenerative farming costs $10 to $100 per ton of carbon dioxide removed from the atmosphere, compared with $100 to $1,000 per ton of carbon dioxide for technologies that mechanically remove carbon from the air, according to a 2020 analysis in Nature Sustainability. Such farming not only makes sense for the environment, but chances are the farmers’ earnings will also increase as they shift to regenerative agriculture, Reddy says.

Farms in Kanumpalli village in Antanapur district grow multiple crops using natural farming methods.M. Shaikshavali

Farmers from the Baiga and Gondh tribal communities in Dholbajja panchayat, India, harvest chiraita, or Andrographis paniculata, a plant used for medicinal purposes. Their Indigenous community recently took up agroforestry and sustainable farming methods.Elsa Remijn photographer, provided by Commonland

Growing solar

Establishing agroecology practices to see an effect on carbon sequestration can take years or decades. But using renewable energy in farming can quickly reduce emissions. For this reason, the nonprofit International Water Management Institute, IWMI, launched the program Solar Power as Remunerative Crop in Dhundi village in 2016.

“The biggest threat climate change presents, specifically to farmers, is the uncertainty that it brings,” says Shilp Verma, an IWMI researcher of water, energy and food policies based in Anand. “Any agricultural practice that will help farmers cope with uncertainty will improve resilience to climate change.” Farmers have more funds to deal with insecure conditions when they can pump groundwater in a climate-friendly way that also provides incentives for keeping some water in the ground. “If you pump less, then you can sell the surplus energy to the grid,” he says. Solar power becomes an income source.

Growing rice, especially lowland rice, which is grown on flooded land, requires a lot of water. On average it takes about 1,432 liters of water to produce one kilogram of rice, according to the International Rice Research Institute. The organization says that irrigated rice receives an estimated 34 to 43 percent of the world’s total irrigation water. India is the largest extractor of groundwater in the world, accounting for 25 percent of global extraction. When diesel pumps do the extracting, carbon is emitted into the atmosphere. Parmar and his fellow farmers used to have to buy that fuel to keep their pumps going.

“We used to spend 25,000 rupees [about $330] a year for running our diesel-powered water pumps. This used to really cut into our profits,” Parmar says. When IWMI asked him in 2015 to participate in a pilot solar-powered irrigation project with zero carbon emissions, Parmar was all ears.

Since then, Parmar and six fellow farmers in Dhundi have sold more than 240,000 kilowatt-hours to the state and earned more than 1.5 million rupees ($20,000). Parmar’s annual income has doubled from 100,000–150,000 rupees on average to 200,000–250,000 rupees.

The boost is helping him educate his children, one of whom is pursuing a degree in agriculture — an encouraging sign in a country where farming is out of vogue with the younger generation. As Parmar says, “Solar power is timely, less polluting and also provides us an additional income. What is not to like about it?”

This aerial image shows solar panels installed among crops to power groundwater pumps and offer a new income source for farmers in western India’s Dhundi village.IWMI-TATA Program, Shashwat Cleantech and Dhundi Saur Urja Utpadak Sahkari Mandali

Parmar has learned to maintain and fix the panels and the pumps himself. Neighboring villages now ask for his help when they want to set up solar-powered pumps or need pump repairs. “I am happy that others are also following our lead. Honestly, I feel quite proud that they call me to help them with their solar pump systems.”

IWMI’s project in Dhundi has been so successful that the state of Gujarat started replicating the scheme in 2018 for all interested farmers under an initiative called Suryashakti Kisan Yojana, which translates to solar power project for farmers. And India’s Ministry of New and Renewable Energy now subsidizes and provides low-interest loans for solar-powered irrigation among farmers.

“The main thing about climate-smart agriculture is that everything we do has to have less carbon footprint,” says Aditi Mukherji, Verma’s colleague and an author of February’s report from the Intergovernmental Panel on Climate Change (SN: 3/26/22, p. 7). “That is the biggest challenge. How do you make something with a low carbon footprint, without having a negative impact on income and productivity?” Mukherji is the regional project leader for Solar Irrigation for Agricultural Resilience in South Asia, an IWMI project looking at various solar irrigation solutions in South Asia.

Back in Anantapur, “there is also a visible change in the vegetation in our district,” Reddy says. “Earlier, there might not be any trees till the eye can see in many parts of the district. Now there is no place which doesn’t have at least 20 trees in your line of sight. It’s a small change, but extremely significant for our dry region.” And Ramesh and other farmers now enjoy a stable, sustainable income from farming.

A family in the village of Muchurami in Anantapur district, India, display vegetables harvested through natural farming methods. The vegetables include pumpkins, peas, spinach, and bottle gourds.M. Shaikshavali

“When I was growing groundnuts, I used to sell it to the local markets,” Ramesh says. He now sells directly to city dwellers through WhatsApp groups. And one of India’s largest online grocery stores, bigbasket.com, and others have started purchasing directly from him to meet a growing demand for organic and “clean” fruits and vegetables.

“I’m confident now that my children too can take up farming and make a good living if they want to,” Ramesh says. “I didn’t feel the same way before discovering these nonchemical farming practices.” More

“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

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