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    Dry farming could help agriculture in the western U.S. amid climate change

    In the parking lot behind a grocery store in Portland, Ore., last September, several hundred tomato aficionados gathered on a sunny, breezy day for Tomato Fest. While many attendees devoured slices of tomato quiche and admired garlands of tomatoes with curiously pointed ends, I beelined to a yellow-tented booth hosted by Oregon State University. Agricultural researcher Matt Davis was handing out samples of experimental tomatoes.

    I took four small plastic bags, each labeled with a cryptic set of letters and numbers and containing a thick slice of a yellow tomato. Scanning a QR code with my phone led me to an online survey with questions about each tomato’s balance of acidity and sweetness, texture and overall flavor. As I chewed on the slice from the bag marked “d86,” I noted the firm, almost meaty texture. Lacking the wateriness of a typical supermarket tomato, it would hold up beautifully in a salad or on a burger, I thought. And most importantly, it was tasty.

    These tomatoes for sale at a farmers market in Portland, Ore., were dry-farmed. The practice saves on water and produces more flavorful fruits and vegetables, advocates say.K. Kornei

    I learned later that this tomato had been dry-farmed, a form of agriculture that doesn’t require irrigation. Dry farming has roots stretching back millennia. But in the western United States, the practice largely fell out of widespread use in the 20th century.

    Today, however, farmers in the West are once again experimenting with dry farming as they grapple with water shortages, which are being exacerbated by rising temperatures and more frequent and intense droughts linked to climate change.

    Finding a more sustainable way to grow food in a thirsty state like California, for example, where agriculture accounts for roughly 80 percent of water usage and where a third of U.S. vegetables are grown, is a top priority. Dry farming won’t solve all of agriculture’s woes, but it offers a way forward, particularly for smaller-scale producers, while drawing less on a scarce natural resource. And even though the practice isn’t without limitations — dry-farmed produce tends to be physically smaller, and harvests are less bountiful overall — its benefits extend beyond water savings: Dry farming can also yield longer-lasting and better-tasting produce.

    How does dry farming work?

    It’s a common misconception that dry farming means growing plants without water. “Nothing grows without water,” says Amy Garrett, president of the nonprofit Dry Farming Institute in Corvallis, Ore. Instead, dry-farmed plants take up moisture stored in the ground rather than sprinkled from above.

    Dry farming is possible in states throughout the West. What’s needed is a wet rainy season, when rainwater infiltrates the soil, followed by a dry growing season, when plant roots pull in that moisture as needed. A wide variety of fruits and vegetables — including tomatoes, potatoes, squash, corn and even watermelons — can be dry-farmed. Dry farming is distinct from rain-fed agriculture, when crops grow during a wet season without the aid of irrigation.

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    For dry farming to work, a couple elements are essential. “You need to be in a place where there’s sufficient rainfall to create moisture in the soil,” says David Runsten, water policy director at the Community Alliance with Family Farmers in Davis, Calif. Sites must generally receive more than 50 centimeters of annual precipitation — in 2022, that was true in 26 of California’s 58 counties, for example — and the soil must be composed of fine grains that help retain that water over time.

    Beyond that, farmers employ a range of techniques to help crops get all the moisture they need. Those methods include planting earlier in the season than usual to take advantage of soil moisture stored up from winter rains and spacing plants more widely to give roots more room to search for water. Farmers can also plant young seedlings in furrows to minimize the drying effects of the wind and lay down an insulating layer of mulch — often leaves, wood chips or straw — on top of the soil.

    Dry farming is standard practice in many places around the world, from olive groves in the Mediterranean to melon fields in Botswana to vineyards in Chile. In the American West, dry farming has a long history stretching back thousands of years among Indigenous peoples.

    “Dry farming is just farming — it’s our way of life,” says Michael Kotutwa Johnson, an Indigenous resiliency specialist at the University of Arizona in Tucson. He’s also a member of the Hopi Tribe and dry-farms corn, lima beans and other crops. He learned the practice from his grandfather.

    The intimate knowledge of the natural world that dry farming requires aligns with the Hopi community’s values and spiritual beliefs, he says. “You get to really learn what the environment gives you, and you learn to reciprocate.” A relationship develops between the cropping system and the farmer, he says. “It’s a beautiful thing, and it’s something that needs to be cherished.”

    Children explore a field of dry-farmed corn on Hopi land in Arizona. Dry farming requires that crops be spaced farther apart than on an irrigated farm so that the plants have enough room to access all of the soil moisture they need.M.K. Johnson

    As non-Indigenous people started arriving in the West, they too began to dry-farm. But by the 20th century, many commercial farmers started relying on irrigation to capture growing markets. Having water on demand gave farmers more control and allowed them to boost production, says Jay Lund, vice director of the Center for Watershed Sciences at the University of California, Davis. “They could have a lot more reliable crop yields, and much higher crop yields.”

    But today, irrigation water in many parts of the West is in short supply. In places like California’s San Joaquin Valley — the state’s largest agricultural region — water is pumped up from deep aquifers and often transported through canals and pipes before being deposited on crops. Researchers estimate that more than a quarter of irrigation water can be lost during transport due to evaporation and leaks. An even bigger problem in this region is that water is being extracted from the ground at a faster rate than it’s being replenished. “There just isn’t sufficient water for the amount of farmland that’s been planted,” Runsten says.

    And access to irrigation is already being curtailed. Farmers in California and other states in the West are experiencing water shortages and have at times been entirely cut off from irrigation (SN: 9/25/21, p. 16).

    That’s not likely to change in the future, Runsten says. To meet the goals of California’s 2014 Sustainable Groundwater Management Act, for instance, more than 200,000 hectares of irrigated farmland in the San Joaquin Valley — roughly 10 percent — will need to be taken out of irrigated production by 2040. Dry-farming speciality crops like agave or jujube, an Asian fruit similar to a date, could be an economically attractive alternative for the land, according to a 2022 report by the nonprofit Public Policy Institute of California.

    Dry farming has pros and cons

    Catherine Nguyen, who farms on a little less than half a hectare of leased land outside of Portland, Ore., in the Willamette Valley, has been dry-farming for two years. Nguyen — whose customers include farmers market shoppers, members of her community supported agriculture, or CSA, program and small restaurants — was drawn to the practice in part out of curiosity. “I love experimentation and with the changing climate and cost of water, it seemed like something to learn more about,” she says. A portion of her property also lacks access to irrigation, so dry farming made it possible to use land that would otherwise remain fallow.

    Potatoes were the first crop Nguyen dry-farmed. Beyond saving roughly 7,500 liters of water, Nguyen and her small crew discovered other benefits. There was no need for sprinklers, drip tape, hosing or any other irrigation equipment. That meant Nguyen’s farm could cut down on a lot of plastic equipment intended to last for just one or two growing seasons. “Not only is our water usage down, but so is our plastic usage,” Nguyen says. That lighter environmental touch is important to Nguyen, who uses farming methods that promote healthy soil ecosystems, including minimal tillage and cover cropping, which involves growing plants specifically to improve the soil rather than for a harvest (SN Online: 4/12/22).

    Last year, Nguyen dry-farmed delicata squash, corn, tomatoes, potatoes and beans. Nguyen noticed that her dry-farmed plots contained only about a fifth of the weeds that grow in her irrigated plots. That’s another known advantage of dry farming, Garrett says. Irrigation creates conditions for weed growth: Dispensing water through above­ground sprinklers causes moisture to pool near the surface, precisely where weeds wait for water, she says. “There is a weed seed bank in the top few inches of soil.”

    Not having to pull up as many weeds or apply herbicides can translate into labor savings. Coupled with not having to manage irrigation infrastructure, dry farming can streamline a growing operation, Garrett says. “There’s a lot less to do.” Labor accounts for more than a quarter of total production costs for U.S. fruit and vegetable farmers.

    Another benefit is that the produce contains less water and therefore tends to store better. In 2016 and 2017, Alex Stone, a horticulturist at Oregon State University, and her student Jennifer Wetzel grew different varieties of winter squash at the university’s research farm in Corvallis. The pair irrigated some vegetable plots and dry-farmed others. After harvesting the squash and leaving them in storage for four months, Stone and Wetzel found that about 1,000 of the roughly 1,250 dry-farmed winter squash, or about 80 percent, were still marketable. But only about 600 of the roughly 1,150 irrigated winter squash, or about 50 percent, were marketable.

    Longer-lasting produce is a boon for small-scale fruit and vegetable growers, Garrett says. Winter is often a slow time sales-wise because there’s not much ripening. Selling stored crops in winter is one way that these farmers can earn an income during that lull. “If winter squash is storing months longer, that makes a huge impact for our local growers,” she says. Produce that lasts longer also means less food waste, both in farmers’ storage bins and in shoppers’ refrigerators and pantries.

    Dry farming does have its downsides, however. The practice tends to produce smaller fruits and vegetables. That’s a natural outcome of withholding irrigation, Lund says. “The plant has less water to feed the growth of the fruit.” And growers, to say nothing of shoppers, can be wary of diminutively sized produce. That’s true among farmers in Oregon, Stone says. “They want a big, red tomato.”

    Overall yields also tend to be lower. Not only does a dry-farmed plant produce fewer fruits or vegetables, but it also needs more space than its irrigated brethren so that its root system can spread out in search of water. Dry-farmed tomatoes, for instance, are typically planted almost two meters apart in rows separated by about two meters. Irrigated tomatoes can grow much closer together, about 60 centimeters apart, with rows separated by a meter or so.

    Stone and Wetzel found that yields of irrigated winter squash at Oregon State’s research farm averaged 35.7 metric tons per hectare in 2016 and 32.2 metric tons in 2017. Dry-farmed squash yields were only 37 to 76 percent as much.

    Diminished harvests can be a challenge. “With land access already being one of the biggest obstacles to farming, sometimes it’s hard for me to justify dry farming,” Nguyen says. Last year, she dry-farmed on only about a tenth of her property. “I do have to consider yield per square foot when deciding how much land to dry-farm,” she says.

    Smaller harvests can translate to more expensive produce. “You don’t have the economies of scale,” Lund says. “Your costs are much higher per unit of production.” Dry-farmed tomatoes, for instance, typically sell for $4–$6 per pound and are primarily found at farmers markets and specialty grocery stores. That’s compared with $2–$3 per pound for traditional supermarket tomatoes grown with irrigation.

    Dry-farmed produce may never become truly mainstream, Johnson says. “I don’t see us moving in that direction as long as we still have a market system that’s based on efficiency and quantity.” But many dry farming experts argue that paying more for dry-farmed produce is an investment in the future. And, they point out, dry-farmed produce tastes better.

    All of these melons were grown in dry farming experiments at Oregon State University’s Vegetable Research Farm. Melons are well-suited to dry farming because they originated in arid locations.A. Garrett

    How does dry farming affect flavor?

    In California’s Napa Valley, there’s nary an irrigation hose snaking through Dominus Estate’s roughly 55-hectare Napanook Vineyard. Every last one of the more than 100,000 cabernet sauvignon, cabernet franc and petit verdot grapevines planted there is dry-farmed.

    The water savings are tremendous, says Tod Mostero, Dominus Estate’s director of viticulture and winemaking. A single irrigated grapevine is typically irrigated with nearly 40 liters of water several times or more over the growing season, he says. For a vineyard the size of Napanook, that translates to nearly 4 million liters, or about a million gallons, for just one watering, Mostero says. In drought-prone California, that’s not sustainable, he says. “Pumping millions of gallons of water out of the soil is not something that we can continue to do.”

    Beyond the water savings, there’s another reason Napanook Vineyard is dry-farmed, Mostero says. The practice produces the best wines, he contends. When grapevines are dry-farmed, the unique flavors of a wine associated with a place, and even a vintage, often shine through. Grapevines can send roots up to six meters deep in search of moisture. As those roots pass through layers of soil and rock, they absorb a complex set of minerals unique to that location, Mostero says. “You really find the terroir, the subtle differences between different areas.” For that very reason, some wine-growing regions, in parts of Europe for example, forbid vineyards from irrigating wine grapes.

    Oenophiles aren’t the only ones swearing by the superior flavors of dry-farmed fruits and vegetables. Laurence Jossel, the chef-owner of Nopa, a restaurant in San Francisco that specializes in wood-fired cuisine, sources dry-farmed tomatoes from local farms. Tomatoes that are bloated with water taste “boring,” Jossel maintains. “The acid is gone, and the sweetness is gone.” He uses dry-farmed tomatoes in everything from soups to flatbreads. Sometimes they’re the star ingredient: A salad of chopped tomatoes topped with a bit of feta or mozzarella is one of Nopa’s summer offerings. “The tomato itself is just amazing,” he says.

    What’s the future of dry farming?

    Despite the environmental benefits of dry farming, some farmers remain wary. Stone has found that growers in Oregon are often cautious about the practice, even when it comes to cultivating varieties that sell well elsewhere. A case in point is Early Girl tomatoes, which are extensively dry-farmed in California and available at both California supermarkets and farmers markets.

    “They just see them as elite, expensive, small tomatoes,” Stone says.

    To explore the economic viability of dry farming, Stone is leading farming trials of dry-farmed crops to determine which varieties are most suited to commercial production. In recent years, she and colleagues have focused on tomatoes, which, after potatoes, are the most commonly consumed vegetable in the United States. (Technically a fruit, tomatoes are considered a vegetable for nutritional and culinary purposes by the U.S. Department of Agriculture.)

    Stone’s team at Oregon State has grown hundreds of types of tomatoes. By recording yields, susceptibility to common diseases like blossom-end rot, and the size, firmness and flavor of the tomatoes, the researchers have started to home in on varieties that thrive — and taste good — when the irrigation is turned off. The first yellow tomato I sampled at Tomato Fest is one of the researchers’ leading contenders.

    Planting tomato seedlings in furrows, as shown on this dry-farmed plot in California, helps prevent the wind from wicking away precious moisture.Carolyn Lagattuta/UC Santa Cruz

    Dry farming offers one way forward as water resources become more unpredictable in the future. But it’s not a one-size-fits-all panacea for climate change, researchers admit. In some cases, crops that once thrived without irrigation may no longer do well at some point in the future.

    “As summers become hotter and drier, crops will require even more water as they will lose more water [through evapotranspiration], making dry farming riskier,” Stone says.

    Some farmers may have to swap one type of crop for another that’s more suited to even drier conditions. Fruit trees with particularly long, deep roots are good bets, Garrett says, as are species like melons that originally evolved in arid locales.

    Whatever the future holds, being adaptable will be key. Farmers must be prepared to respond to changing conditions, Johnson says, but must also allow nature to lead. After all, that’s worked for his community for thousands of years.

    “We raise corn to fit the environment,” he says. “We do not manipulate the environment to fit the corn.” More

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    An incendiary form of lightning may surge under climate change

    A form of lightning with a knack for sparking wildfires may surge under climate change.

    An analysis of satellite data suggests “hot lightning” — strikes that channel electrical charge for an extended period — may be more likely to set landscapes ablaze than more ephemeral flashes, researchers report February 10 in Nature Communications. Each 1 degree Celsius of warming could spur a 10 percent increase in the most incendiary of these Promethean bolts, boosting their flash rate to about four times per second by 2090 — up from nearly three times per second in 2011.

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    That’s dangerous, warns physicist Francisco Javier Pérez-Invernón of the Institute of Astrophysics of Andalusia in Granada, Spain. “There will be more risk of lightning-ignited wildfires.”

    Among all the forces of nature, lightning sets off the most blazes. Flashes that touch down amid minimal or no rainfall — known as dry lightning — are especially effective fire starters. These bolts have initiated some of the most destructive wildfires in recent years, such as the 2020 blazes in California (SN: 12/21/20).

    But more than parched circumstances can influence a blast’s ability to spark flames. Field observations and laboratory experiments have suggested the most enduring form of hot lightning — “long continuing current lightning”— may be especially combustible. These strikes channel current for more than 40 milliseconds. Some last longer than one-third of a second — the typical duration of a human eye blink.

    “This type of lightning can transport a huge amount of electrical discharge from clouds to the ground or to vegetation,” Pérez-Invernón says. Hot lightning’s flair for fire is analogous to lighting a candle; the more time a wick or vegetation is exposed to incendiary energy, the easier it kindles.

    Previous research has proposed lightning may surge under climate change (SN: 11/13/14). But it has remained less clear how hot lightning — and its ability to spark wildfires — might evolve.

    Pérez-Invernón and his colleagues examined the relationship between hot lightning and U.S. wildfires, using lightning data collected by a weather satellite and wildfire data from 1992 to 2018.

    Long continuing current lightning could have sparked up to 90 percent of the roughly 5,600 blazes encompassed in the analysis, the team found. Since less than 10 percent of all lightning strikes during the summer in the western United States have long continuing current, the relatively high ignition count led the researchers to infer that flashes of hot lightning were more prone to sparking fire than typical bolts.

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    The researchers also probed the repercussions of climate change. They ran computer simulations of the global activity of lightning during 2009 to 2011 and from 2090 to 2095, under a future scenario in which annual greenhouse gas emissions peak in 2080 and then decline.

    The team found that in the later period, climate change may boost updraft within thunderstorms, causing hot lightning flashes to increase in frequency to about 4 strikes per second globally — about a 40 percent increase from 2011. Meanwhile, the rate of all cloud-to-ground strikes might increase to nearly 8 flashes per second, a 28 percent increase.

    After accounting for changes in precipitation, humidity and temperature, the researchers predicted wildfire risk will significantly increase in Southeast Asia, South America, Africa and Australia, and risk will go up most dramatically in North America and Europe. However, risk may decrease in many polar regions, where rainfall is projected to increase while hot lightning rates remain constant.

    It’s valuable to show that risk may evolve differently in different places, says Earth systems scientist Yang Chen of the University of California, Irvine, who was not involved in the study. But, he notes, the analysis uses sparse data from polar regions, so there is a lot of uncertainty. Harnessing additional data from ground-based lightning detectors and other data sources could help, he says. “That [region is] important, because a lot of carbon can be released from permafrost.”

    Pérez-Invernón agrees more data will help improve projections of rates of lightning-induced wildfire, not just in the polar regions, but also in Africa, where blazes are common but fire reports are lacking. More

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    Air pollution made an impression on Monet and other 19th century painters

    The 19th century landscape paintings hanging in London’s Tate Britain museum looked awfully familiar to climate physicist Anna Lea Albright. Artist Joseph Mallord William Turner’s signature way of shrouding his vistas in fog and smoke reminded Albright of her own research tracking air pollution.“I started wondering if there was a connection,” says Albright, who had been visiting the museum on a day off from the Laboratory for Dynamical Meteorology in Paris. After all, Turner — a forerunner of the impressionist movement — was painting as Britain’s industrial revolution gathered steam, and a growing number of belching manufacturing plants earned London the nickname “The Big Smoke.”

    Turner’s early works, such as his 1814 painting “Apullia in Search of Appullus,” were rendered in sharp details. Later works, like his celebrated 1844 painting “Rain, Steam and Speed — the Great Western Railway,” embraced a dreamier, fuzzier aesthetic.

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    Perhaps, Albright thought, this burgeoning painting style wasn’t a purely artistic phenomenon. Perhaps Turner and his successors painted exactly what they saw: their environs becoming more and more obscured by smokestack haze.

    To find out how much realism there is in impressionism, Albright teamed up with Harvard University climatologist Peter Huybers, who’s an expert in reconstructing pollution before instruments existed to closely track air quality. Their analysis of nearly 130 paintings by Turner, Paris-based impressionist Claude Monet and several others tells a tale of two modernizing cities.

    Low contrast and whiter hues are hallmarks of the impressionist style. They are also hallmarks of air pollution, which can affect how a distant scene looks to the naked eye. Tiny airborne particles, or aerosols, can absorb or scatter light. That makes the bright parts of objects appear dimmer while also shifting the entire scene’s color toward neutral white.

    The artworks that Albright and Huybers investigated, which span from the late 1700s to the early 1900s, decrease in contrast as the 19th century progresses. That trend tracks with an increase in air pollution, estimated from historical records of coal sales, Albright and Huybers report in the Feb. 7 Proceedings of the National Academy of Sciences.

    “Our results indicate that [19th century] paintings capture changes in the optical environment associated with increasingly polluted atmospheres during the industrial revolution,” the researchers write.

    Albright and Huybers distinguished art from aerosol by first using a mathematical model to analyze the contrast and color of 60 paintings that Turner made between 1796 and 1850 as well as 38 Monet works from 1864 to 1901. They then compared the findings to sulfur dioxide emissions over the century, estimated from the trend in the annual amount of coal sold and burned in London and Paris. When sulfur dioxide reacts with molecules in the atmosphere, aerosols form.

    The early works of British painter Joseph Mallord William Turner, such as “Apullia in Search of Appullus,” left, painted in 1814, were rendered in sharp details. His later works, like “Rain, Steam and Speed — the Great Western Railway,” right, painted in 1844, embraced a dreamier aesthetic. The decrease in contrast between the paintings tracks with increasing air pollution from the industrial revolution, researchers say.From left: Apullia in Search of Appullus vide Ovid, Joseph Mallord William Turner/The Tate Collection (CC BY-NC-ND 3.0); World History Archive/Alamy Stock Photo

    As sulfur dioxide emissions increased over time, the amount of contrast in both Turner’s and Monet’s paintings decreased. However, paintings of Paris that Monet made from 1864 to 1872 have much higher contrast than Turner’s last paintings of London made two decades earlier.

    The difference, Albright and Huybers say, can be attributed to the much slower start of the industrial revolution in France. Paris’ air pollution level around 1870 was about what London’s was when Turner started painting in the early 1800s. It confirms that the similar progression in their painting styles can’t be chalked up to coincidence, but is guided by air pollution, the pair conclude.

    The researchers also analyzed the paintings’ visibility, or the distance at which an object can be clearly seen. Before 1830, the visibility in Turner’s paintings averaged about 25 kilometers, the team found. Paintings made after 1830 had an average visibility of about 10 kilometers. Paintings made by Monet in London around 1900, such as “Charing Cross Bridge,” have a visibility of less than five kilometers. That’s similar to estimates for modern-day megacities such as Delhi and Beijing, Albright and Huybers say.

    To strengthen their argument, the researchers also analyzed 18 paintings from four other London- and Paris-based impressionists. Again, as outdoor air pollution increased over time, the contrast and visibility in the paintings decreased, the team found. What’s more, the decrease seen in French paintings lagged behind the decrease seen in British ones.

    Overall, air pollution can explain about 61 percent of contrast differences between the paintings, the researchers calculate. In that respect, “different painters will paint in a similar way when the environment is similar,” Albright says. “But I don’t want to overstep and say: Oh, we can explain all of impressionism.” More

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    Greta Thunberg’s new book urges the world to take climate action now

    The Climate BookGreta ThunbergPenguin Press, $30

    The best shot we have at minimizing the future impacts of climate change is to limit global warming to 1.5 degrees Celsius. Since the Industrial Revolution began, humankind has already raised the average global temperature by about 1.1 degrees. If we continue to emit greenhouse gases at the current rate, the world will probably surpass the 1.5-degree threshold by the end of the decade.

    That sobering fact makes clear that climate change isn’t just a problem to solve someday soon; it’s an emergency to respond to now. And yet, most people don’t act like we’re in the midst of the greatest crisis humans have ever faced — not politicians, not the media, not your neighbor, not myself, if I’m honest. That’s what I realized after finishing The Climate Book by Greta Thunberg.

    The urgency to act now, to kick the addiction to fossil fuels, practically jumps off the page to punch you in the gut. So while not a pleasant read — it’s quite stressful — it’s a book I can’t recommend enough. The book’s aim is not to convince skeptics that climate change is real. We’re well past that. Instead, it’s a wake-up call for anyone concerned about the future.

    A collection of bite-size essays, The Climate Book provides an encyclopedic overview of all aspects of the climate crisis, including the basic science, the history of denialism and inaction, and what to do next. Thunberg, who became the face of climate activism after starting the Fridays For Future protests as a teenager (SN: 12/16/19), assembles an all-star roster of experts to write the essays.

    The first two sections of the book lay out how a small amount of warming can have major, far-reaching effects. For some readers, this will be familiar territory. But as each essay builds on the next, it becomes clear just how delicate Earth’s climate system is. What also becomes clear is the significance of 1.5 degrees (SN: 12/17/18). Beyond this point, scientists fear, various aspects of the natural world might reach tipping points that usher in irreversible changes, even if greenhouse gas emissions are later brought under control. Ice sheets could melt, raise sea levels and drown coastal areas. The Amazon rainforest could become a dry grassland.

    The cumulative effect would be a complete transformation of the climate. Our health and the livelihood of other species and entire ecosystems would be in danger, the book shows. Not surprisingly, essay after essay ends with the same message: We must cut greenhouse gas emissions, now and quickly.

    Repetition is found elsewhere in the book. Numerous essays offer overlapping scientific explanations, stats about emissions, historical notes and thoughts about the future. Rather than being tedious, the repetition reinforces the message that we know what the climate change threat is, we know how to tackle it and we’ve known for a long time.

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    Thunberg’s anger and frustration over the decades of inaction, false starts and broken pledges are palpable in her own essays that run throughout the book. The world has known about human-caused climate change for decades, yet about half of all human-related carbon dioxide emissions ever released have occurred since 1990. That’s the year the Intergovernmental Panel on Climate Change released its first report and just two years before world leaders met in Rio de Janeiro in 1992 to sign the first international treaty to curb emissions (SN: 6/23/90).

    Perversely, the people who will bear the brunt of the extreme storms, heat waves, rising seas and other impacts of climate change are those who are least culpable. The richest 10 percent of the world’s population accounts for half of all carbon dioxide emissions while the top 1 percent emits more than twice as much as the bottom half. But because of a lack of resources, poorer populations are the least equipped to deal with the fallout. “Humankind has not created this crisis,” Thunberg writes, “it was created by those in power.”

    That injustice must be confronted and accounted for as the world addresses climate change, perhaps even through reparations, Olúfẹ́mi O. Táíwò, a philosopher at Georgetown University, argues in one essay.

    So what is the path forward? Thunberg and many of her coauthors are generally skeptical that new tech alone will be our savior. Carbon capture and storage, or CCS, for example, has been heralded as one way to curb emissions. But less than a third of the roughly 150 planned CCS projects that were supposed to be operational by 2020 are up and running.

    Progress has been impeded by expenses and technology fails, science writer Ketan Joshi explains. An alternative might be “rewilding,” restoring damaged mangrove forests, seagrass meadows and other ecosystems that naturally suck CO2 out of the air (SN: 9/14/22), suggest environmental activists George Monbiot and Rebecca Wrigley.

    Fixing the climate problem will not only require transforming our energy and transportation systems, which often get the most attention, but also our economies (endless growth is not sustainable), political systems and connection to nature and with each other, the book’s authors argue.

    The last fifth of the book lays out how we could meet this daunting challenge. What’s needed is a critical mass of individuals who are willing to make lifestyle changes and be heard. This could trigger a social movement strong enough to force politicians to listen and create systemic and structural change. In other words, it’s time to start acting like we’re in a crisis. Thunberg doesn’t end the book by offering hope. Instead, she argues we each have to make our own hope.

    “To me, hope is not something that is given to you, it is something you have to earn, to create,” she writes. “It cannot be gained passively, through standing by and waiting for someone else to do something. Hope is taking action.”

    Buy The Climate Book from Science News is a affiliate and will earn a commission on purchases made from links in this article. More