As the planet warms, the land becomes drier and more salinous, with serious consequences for the planet’s eight billion inhabitants. Nearly a third of these people live in areas where water is already becoming increasingly scarce and the ability to raise crops and livestock is becoming increasingly difficult.
Climate change is accelerating this trend. Global warming has made 77% of Earth’s land drier over the past 30 years, and the proportion of soils that are too salty has increased dramatically, according to a new study.
Drylands, or dry areas where water is difficult to obtain, now cover more than 40% of the Earth (excluding Antarctica). This is likely to be a permanent consequence of climate change. According to a groundbreaking report: Another new analysis by the Food and Agriculture Organization of the United Nations (FAO) under the United Nations Convention to Combat Desertification (UNCCD) found that roughly: 10% of the world’s soil Another 2.5 billion acres are at risk from the effects of excessive salinity.
These intertwined trends threaten agricultural productivity, biodiversity and ecosystem health while worsening food and water insecurity. Together, the two reports sound an urgent warning. Unless the world curbs emissions, these changes will continue and have serious impacts.
“Without our collective efforts, billions of people will face a future marked by hunger, displacement and economic decline.” said Nichole Barger, a dryland ecologist working with UNCCD.
Between 1990 and 2020, approximately 7.6% of Earth’s land has been recreated due to climate change, with most of the affected areas moving from wet to dry regions. This is defined as the area where 90% of rainfall evaporates before reaching the ground. Researchers found that these two regions cover a larger geographic area than Canada, and in 2020, approximately 30% of the world’s population lived here. This represents an increase of more than 7% in recent decades. Unless the world drastically limits emissions, that rate could more than double by the end of the century. By that point, more than two-thirds of the world’s land mass, excluding Greenland and Antarctica, is expected to store less water.
These changes are not limited to areas already considered dry or expected to experience desertification. When modeling global high-emissions scenarios, researchers found that similar changes could occur in the Midwest, central Mexico, and the Mediterranean, to name three examples. Researchers have no expectations that this trend will reverse.
A new report says wetland protection could be down to farmers.
What’s “important and hard to emphasize,” said Hannah Waterhouse, a soil and water scientist at the University of California, Santa Cruz, is that this expansion occurred under conditions that were not as hot as what was to come. This will further escalate the problem, she said, leading to problems such as widespread conflict as food and water become increasingly scarce.
“We can look at geopolitical and ecological events that are happening now to understand what we can expect in the future,” Waterhouse said. “Consider what is happening in Sudan now, where resource scarcity is worsening due to climate change and where governance and geopolitics are interacting to produce violent consequences for civilians.”
Dryness should not be confused with drought. Droughts are sudden and surprising, but are best described as temporary water shortages caused by low rainfall, high temperatures, low humidity and unusual wind patterns. On the other hand, arid regions experience persistent, long-term climatic conditions in which evaporation exceeds precipitation, creating conditions that can make life difficult to sustain. It’s much more subtle than drought, but no less significant.
“The drought is over,” said UNCCD Secretary-General Ibrahim Thiaw. said in a statement. “But as the climate in your region becomes drier, you lose the ability to return to previous conditions. “The drier climate that now affects vast swaths of land around the world will never return to its former state, and these changes are redefining life on Earth.”
Dryland expansion is widely believed to be the biggest contributor to the deterioration of Earth’s agricultural systems and difficulties in producing enough food. These situations are also associated with loss of gross domestic product (GDP), mass migration, negative health impacts and increased mortality. They intensify forest fires, sandstorms and dust storms while destroying ecosystems. They also promote erosion and salinization of water and soil.
Climate change is already disrupting food production, with one in 11 people worldwide suffering from hunger last year. Studies show that the problem will worsen, especially in most parts of Africa, the Middle East and South Asia. Under a business-as-usual emissions scenario, sub-Saharan Africa could lose up to 22% of its current crop production capacity by 2050. Rice could also plummet globally.
The rapid expansion of the world’s drylands is “100% interconnected” with the proliferation of highly saline soils, said Maria, a soil scientist at the Food and Agriculture Organization and lead author of a report released Dec. 11 by the U.N. agency. Maria Konyushkova said: The smaller the area, the less fresh water is available. This requires farmers to rely on brackish water to increase soil salinity.
Soluble salts are a component of all soils, but too much of them can interfere with water absorption by plants, effectively depriving them of moisture and inhibiting growth. High salinity can also change soil structure, making it more prone to erosion. All of this could reduce soil fertility and lead to yield losses of up to 70% for crops such as rice and soybeans in the most affected countries, the researchers said. About 10% of the world’s irrigated agricultural land and a similar proportion of rainfed agricultural land have already been affected by this dire trend.
Currently, 10 countries, including China, Russia, and the United States, account for 70% of the Earth’s salty soil. This costs the global agricultural sector at least $27 billion each year. If the world continues to warm at its current rate, past research It is estimated that by 2050, more than 50% of the world’s agricultural land will be similarly affected, worsening the decline in yields that is already driving hunger rates.
Where to go from here was a key topic at UNCCD COP16 earlier this month. Representatives from nearly 200 countries gathered in Riyadh, Saudi Arabia to discuss land degradation, desertification and drought. UN Secretary-General António Guterres: “We depend on the land for our survival” said at the meeting. “But we treat it like dirt.”
Nature-based solutions such as agroecology are among the locally applied mitigation and adaptation tactics proposed by both reports, along with improved crop and water management, technological solutions and the development of water-efficient and salt-tolerant crop varieties.
Large-scale investments are also being discussed as a solution. Former UNCCD report They found that halting the pace of Earth’s land degradation could cost the global economy $23 trillion by 2050, costing an estimated $4.6 trillion. The agency told negotiators at the summit: At least $2.6 trillion Required for restoration and resilience purposes by 2030.
By the end of the summit, just over $12 billion had been pledged to address the issue in 80 vulnerable countries, and negotiators left without being able to agree on a legally binding protocol for action.
Waterhouse has reservations about some of the proposals highlighted in the study, which he views as “top-down technological solutions.” An example is the Great Green Wall, a multibillion-dollar plan to plant trees to prevent desertification in Africa’s Sahel region. This effort, which began in 2007, draw criticism To worsen water scarcity and biodiversity loss.
Konyushkova sees both reports as an urgent call for governments around the world to prioritize investing in resilience efforts to manage what is clearly becoming a crisis. “All trends show that freshwater resources will be depleted, but we have so many approaches to adapt,” she said. “We just need to start doing it now. Because it’s already here. “It’s already there and it’s getting worse, even if governments don’t always understand it.”
