Latest news with #Hultgren
Yahoo
01-07-2025
- Science
- Yahoo
What does climate change mean for agriculture? Less food, and more emissions
New research spotlights the challenge of growing food on a warming planet. Two recent studies — one historical and the other forward-looking — examine how rising temperatures have made and could continue to make agricultural production less efficient, fundamentally reshaping the global food system as producers try to adapt to hotter growing seasons. The findings illuminate the bind that farmers and consumers find themselves in. Agricultural production is a driver of climate change; it's estimated to be responsible for somewhere between a quarter and a third of global greenhouse gas emissions. But it is also hampered by the changes in weather patterns associated with climate change. While producers struggle to harvest the same amounts of food in the face of droughts, heat waves, and hurricanes, shoppers are more likely to face climbing food prices. The forward-looking study, published June 18 in Nature, analyzes the impact of warming temperatures on the caloric output of agricultural production. Researchers at the University of Illinois Urbana-Champaign and the Stanford Doerr School of Sustainability found that for every additional degree Celsius of warming above the 2000-2010 average, the global food system will produce roughly 120 fewer calories per person per day. In a scenario where the Earth experiences 3 degrees Celsius of warming by the end of the century, that's the equivalent of everyone on the planet missing out on breakfast, said Andrew Hultgren, lead author of the study. Hultgren and his colleagues compiled a massive dataset on the production of six staple crops in more than 12,000 regions spread out over 54 countries. They then modeled how different warming scenarios might impact crop production; they also factored in how farmers around the world are adapting to higher temperatures. What they found is that, even with adaptation, global warming is associated with an 'almost a linear decline in caloric output,' said Hultgren, who is also an assistant professor of agricultural and consumer economics at the University of Illinois Urbana-Champaign. Measuring agricultural adaptation and its impact on output was important, said Hultgren, because research often assumes that farmers either adapt perfectly to global warming or not at all. The reality is that adapting to any growing season challenges comes at some cost, and farmers are constantly weighing the business benefits of implementing new techniques. For example, one tool that corn farmers in the U.S. Midwest have to prevent hot days from thwarting their harvest is planting crop varietals that mature relatively quickly. 'Corn is very sensitive to extreme heat,' said Hultgren, 'so one very hot day can actually be bad for your entire growing season yield.' But fast-maturing varietals also often produce lower yields overall, meaning these farmers likely can't sell as much corn as they would have under cooler weather conditions, said Hultgren. 'So there's literally a cost of avoiding that extreme heat,' he said. A drop in the global supply of crops will also lead to an uptick in food prices. But Hultgren noted that the impacts of reduced agricultural output won't be evenly distributed. In wealthier countries such as the U.S., for example, those who can afford higher food prices will likely eat the cost. In poorer countries, these shifts could worsen food insecurity. Additionally, rising temperatures will impact producers unevenly; the study estimated that in a high-warming climate scenario, corn farmers in the U.S. will experience 40 to 50 percent losses in yield by the end of the century. Based on these projections, 'you wonder if the Corn Belt continues to be the Corn Belt,' said Hultgren. Meanwhile, other regional producers — like rice farmers in South and Southeast Asia — will see yields grow in the same time frame. 'There are absolutely regional winners and losers in this global aggregate,' he said. The historical study, published June 20 in Nature Geosciences, looks at one of the ways agricultural production contributes to global warming: land clearing. When farmers want to cultivate new cropland, they often start by removing the plants that are already growing there, whether that's grass, shrubs, or trees. When land clearing happens in carbon-rich regions in the Global South, like the Amazon rainforest, it increases deforestation and carbon emissions, said Jessica Till, the study's co-lead author. 'Deforestation in tropical areas is one of the most urgent issues and biggest areas of concern,' said Till, a research scientist at the University of Illinois Urbana-Champaign. (Till and Hultgren were not involved in each other's studies.) 'The more land you clear, the more forest you remove to create cropland, that's going to have a negative effect on the climate.' Till and the other study authors examined this feedback loop between agriculture and the environment: When crop production becomes less efficient due to extreme weather and heat, farmers must acquire and clear more land to boost production. That expansion in croplands then in turn results in higher greenhouse gas emissions, which exacerbates warming and makes crop production even less efficient. They found that, even with improvements in agricultural productivity (due to technological improvements like new seed varieties and precision fertilizer application), climate change was responsible for 88 million hectares, or 217 million acres, in cropland expansion globally — an area roughly twice the size of California — between 1992 and 2020. They also determined that this expansion was led by major agricultural producers, including the United States, India, China, Russia, and Brazil. Unsurprisingly, these countries were also the top five highest emitters of greenhouse gas emissions stemming from climate-driven expansions in cropland. Both Till and Hultgren noted that these shifts can also influence global trade. When certain regions see a decline in agricultural productivity, said Till, other regions will gain a competitive advantage in the international market for agricultural commodities. Erwan Monier, co-director of the Climate Adaptation Research Center at the University of California Davis, said he was not surprised by either studies' findings, and said they contribute to the growing body of research on climate impacts on agriculture. But he added that both come with caveats. Monier noted that the Nature study on caloric output fails to consider possible future advances in technologies like genetic editing that could make crops much more resilient to climate change. He said the paper demonstrates that 'in order to really limit the impact of climate on our ability to grow food, we're going to need a scale of innovation and adaptation that is really substantial, and that's going to be a real challenge.' Referring to the Nature Geosciences paper on the feedback loop between agriculture and climate, Monier said that it similarly does not take into account how farmer behavior might change in response to global warming. 'The fact is we have an ability to change what grows where,' said Monier. In the U.S., for example, where corn and soy production reign, farmers could choose to plant different crops if they see yields fall consistently. These growers will not 'continue growing corn with very low yields and invest more capital and land with very, very low returns,' said Monier. 'Farmers are going to move away to something that actually is more valuable and grows well' — and that, in turn, could reduce the need to clear more land. Monier acknowledged that the latter study might come across as quite pessimistic. But, he said, it underscores the importance of having difficult conversations now about how to grow enough food to feed the world's population as temperatures climb. In order to avoid serious losses in agricultural production, he said, climate researchers and institutions must work hand-in-hand with farmers, helping them understand the risks of global warming and seek out new ways of adapting. This work should be 'bottom up,' said Monier, rather than 'top down.' 'We need to engage the people who are going to be actually growing the food.' He added that this will involve work that extends beyond the academic sphere. 'I don't know if publishing in Nature and Nature Geoscience is the way to really drive the bottom-up adaptation at the scale that is necessary.' This story was originally published by Grist with the headline What does climate change mean for agriculture? Less food, and more emissions on Jun 30, 2025.

18-06-2025
- Business
What farmers' adaptation to climate change means for the future of food
Think food prices are high now? By the end of this century, climate change could significantly cut production of six staple food crops around the world — including wheat production in Canada, leading to higher prices, a new study finds. And certain crops in higher-income regions, such as corn and wheat in the U.S. Midwest and wheat in Canada's Prairies, could see some of the bigger losses compared to crops in developing countries, projects the study published Wednesday in the journal Nature (new window) . Better-off parts of the world end up getting harmed in ways that are surprising that I didn't expect, said lead author Andrew Hultgren, an assistant professor of agricultural and consumer economics at the University of Illinois Urbana-Champagne. But farmers' adaptation will make a difference. Meanwhile, Canada does have some options and may fare better than other parts of the world. The study looked at data about regional climates; climate impacts on specific crops; access to resources such as fertilizer and insurance and costs and benefits of different farming practices for farmers in 54 countries that grow corn, soybeans, rice, wheat, cassava and sorghum. The goal was to find out how farmers are adapting to weather shocks and the extent to which adaptation is offsetting the impacts of climate change. In a high-emissions scenario, where global temperatures warm by 3.2 to 5.4 C by 2090 (new window) , corn production is expected to decline up to 40 per cent in the U.S., eastern China, central Asia, southern Africa and the Middle East; and wheat production is expected to fall 30 to 40 per cent in China, Russia, the U.S. and Canada. Enlarge image (new window) Maps show average yield losses for different crops in a high-emissions scenario with adaptation. Photo: Nature 2025 / Hultgren et al. Adaptation makes some difference Some of the losses in developing countries will be offset by growing wealth in those countries that allows them to mechanize to increase productivity. Adaptation strategies, such as growing different varieties and adjusting fertilizer use and irrigation, can also help, offsetting about one-third of global agricultural losses. That's good, Hultgren said. But it's not everything. But even with adaptation, the study projected a 25 per cent productivity loss globally by 2100 among the six crops it looked at. The United Nations projects that we're on track to warm as much as 2.9 C by the end of the century (new window) — less than the high emissions scenario. Hultgren said even with warming of only 3 C, global production would be lowered by the amount of calories that people eat for breakfast every day. Enlarge image (new window) This graph from the study shows how the availability of food calories will be affected with a rise in global mean surface temperature. Photo: Nature 2025 / Hultgren et al. That could lead to higher prices in higher-income countries, and social and political instability in poorer countries, where many people could have trouble affording food. These results indicate a scale of innovation, cropland expansion or further adaptation that might be necessary to ensure food security in a changing climate, the study concludes. More harm in higher-income countries? Hultgren and his research team found that while losses in low-income regions were substantial, they were bigger in productive farming areas in higher-income areas such as the U.S., Canada and western Europe. That's because many poorer countries have already done much more adaptation, Hultgren said — they're already facing more extreme heat and don't have access to resources such as insurance, requiring them to be more risk averse. WATCH | India tries to adapt to the threat of extreme heat : Début du widget Widget. Passer le widget ? Fin du widget Widget. Retourner au début du widget ? Gurcharn Brar, the principal investigator of the Cereal Breeding Lab at the University of Alberta, grew up in the wheat-growing Punjab region of India. He said his parents tell him it used to have cooler winters necessary for good yields. But now the winter is shorter and wheat may be exposed to extreme heat while flowering. That may prevent it from producing seeds or cause it to produce smaller seeds. Climate change is already affecting yields in that part of India, he said. I think we do not realize it as much… we still have cooler summers. While the lower level of adaptation means higher-income countries have lots of room to adapt, Hultgren notes that adaptation is costly. For example, more varieties that flower earlier in the season before extreme heat hits may have lower yields. Adaptation, crop switching happening in Canada Brar is developing new wheat varieties for commercial cultivation in northern parts of the Prairies, known as the Parkland region. He said Canada still has cooler summers, but wheat here has already been affected by more frequent droughts, since the crop mostly relies on rain rather than irrigation. He said some losses in Canada have already been offset by growing improved, higher yielding wheat varieties — although they would be seeing bigger gains in yield without climate change. We know that varieties that will be grown 10 years from now…should stand drought and heat better, he said. Researchers are already developing them, as it takes eight to 12 years. Developing a new variety also costs about $1 million on average, he said. Enlarge image (new window) The Reid family harvests their wheat crop near Cremona, Alta., on Sept. 19, 2023. Photo: The Canadian Press / Jeff McIntosh Gunter Jochum runs Blue Diamond Farms west of Winnipeg and is growing wheat, oats, canola and soybeans on 2,550 hectares with his brother-in-law. He's been farming the region for 40 years and is also the president of the Western Canadian Wheat Growers Association. Jochum said he and other farmers are constantly improving their farming practices, technology, and changing their crops and varieties to suit changing conditions in the climate and the market. Despite challenging swings between wet and dry conditions in recent decades, he said, our yields still seem to be able to go up every year because of the way we change farming — the way we adapt to the climate, to the changes. In Canada's case, the study shows that while wheat yields may decline in some areas, they could increase for crops such as corn and soybeans in more northern areas. WATCH | Tool crunches weather data to help grain producers avoid costly disease: Début du widget Widget. Passer le widget ? Fin du widget Widget. Retourner au début du widget ? Jochum said that's already happening in his region. Until 2000, no one thought to grow soybeans there because it was too cold, but in the last 20 years, they've become a really important crop on our farm, in our area. That's partly because a warming climate has extended the growing season slightly and partly because scientists have developed faster-growing varieties. In the last five years, corn has really taken off in southern Manitoba, he added. While he sees bigger risks and issues closer to the equator, he thinks Canadian farmers are well-placed to adapt to the changing climate if they have the right support. His group is pushing for more government investment in new varieties of crops and policies that encourage the private sector to develop new varieties. Emily Chung (new window) · CBC News · Science, Climate, Environment Reporter Emily Chung covers science, the environment and climate for CBC News. She has previously worked as a digital journalist for CBC Ottawa and as an occasional producer at CBC's Quirks & Quarks. She has a PhD in chemistry from the University of British Columbia. In 2019, she was part of the team that won a Digital Publishing Award for best newsletter for What on Earth. You can email story ideas to Subscribe to the What on Earth newsletter (new window)


The Hill
18-06-2025
- Science
- The Hill
Climate change cuts crop yields, even with adaptation efforts: Study
Climate-induced warming is jeopardizing the global food supply even as farmers take adaptive measures to stymie these effects, scientists are warning. In contrast with previous research suggesting that warming could actually bolster food production, a new study, published in Nature on Wednesday, finds the opposite. For every additional degree Celsius the planet warms, its ability to produce food could decrease by 120 calories per person per day, or 4.4 percent of the current daily consumption, according to the study. 'If the climate warms by 3 degrees, that's basically like everyone on the planet giving up breakfast,' senior author Solomon Hsiang, a professor of environmental social sciences at Stanford University, said in a statement. Another serious side effect, Hsiang warned, could be price surges that infringe upon access to food for families across the world. U.S. agriculture is expected to suffer significant losses, particularly in the Midwest, the researchers noted. Lead author Andrew Hultgren, an assistant professor of agricultural and consumer economics at the University of Illinois Urbana-Champaign, warned that U.S. corn and soybean production could 'just get hammered under a high warming future.' 'You do start to wonder if the Corn Belt is going to be the Corn Belt in the future,' Hultgren said in a statement. Hsiang and Hultgren, together with more than a dozen scholars, worked over the past eight years to draw observations from more than 12,000 regions across 55 countries. They analyzed adaptation costs and yield for crops responsible for two-thirds of the planet's calories: wheat, rice, soybeans, barley and cassava. They found that previous studies failed to consider what adaptation measures might be realistic for farmers — assuming that they would implement either 'perfect' adaptation protocols or none at all. The researchers estimated that adjustments farmers are making — such as switching crops, shifting planting and harvesting dates and altering fertilizer — could offset about a third of climate-related losses in 2100 amid rising emissions. But the rest of the losses, they stressed, would remain. 'Any level of warming, even when accounting for adaptation, results in global output losses from agriculture,' Hultgren said. Overall, the researchers found that yield losses could amount to about 41 percent in the wealthiest regions and 28 percent in lowest income areas by 2100. There is a 50 percent chance that the world's rice yields could rise, because rice thrives on warm nights, while there is a 70 to 90 percent chance that the other staple crops will decline, according to the study. In the shorter-term, the authors estimated that climate change would bring down global crop production by about 8 percent by 2050, regardless of the rise or fall of emissions. This is because carbon dioxide emissions, they explained, stay in the atmosphere, trapping heat for the long haul. Going forward, the scientists said they are working with the United Nations Development Program to raise awareness about their findings among governments. They are also creating a system to determine which communities are most at risk of declines and could benefit from targeted support. 'Farmers know how to maintain the soil, invest in infrastructure, repair the barn,' Hsiang said. 'But if you're letting the climate depreciate, the rest of it is a waste. The land you leave to your kids will be good for something, but not for farming.'