‘Biggest, baddest' rainfall events are getting worse
Flash floods have wreaked havoc across the country this summer, transcending geography, topography and the built environment from the rural Southwest to the largest cities in the Midwest and Northeast.
The outcomes have been fueled, in each case, by slightly different factors. Hard concrete surfaces in Chicago and New York forced rainwater to pool in the streets or pour into the subways. Wildfire scars near Ruidoso, New Mexico, left the soil loose and vulnerable to floods. Hilly terrain in Kerr County, Texas, sent runoff cascading into the nearby Guadalupe River, which swiftly overflowed its banks.
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But a common ingredient triggered them all: explosions of torrential — and in some cases, record-breaking — rainfall.
These heavy precipitation events are among the clearest symptoms of climate change, scientists say. Copious studies warn that they're already happening more often and becoming more intense, and they'll continue to worsen as global temperatures rise.
And the most catastrophic rainfall events may be worsening the fastest, some experts say.
'The biggest, baddest, rarest extreme precipitation events are precisely those which are going to increase the most in a warming climate,' Daniel Swain, a climate scientist at the California Institute for Water Resources, said in a live YouTube talk shortly after the Texas floods struck in July. 'There is really abundant scientific evidence for this at this point.'
Intensifying rainfall events are the product of simple physics, scientists explain. A warmer atmosphere can hold more water, increasing the odds that moisture-laden clouds will drop rainfall bombs when they burst.
That rule has been well established for nearly 200 years. A 19th-century equation known as the Clausius-Clapeyron relation — still widely referenced by researchers today — dictates that air can hold about 7 percent more moisture with every degree Celsius of warming.
But in recent years, scientists have noticed an alarming trend. Extreme storms in some parts of the world appear to be defying the Clausius-Clapeyron relation, producing far more rainfall as temperatures rise than the equation would predict.
One recent study examined the influence of climate change on the unusually active 2020 Atlantic hurricane season. It noted that extreme short-term rainfall rates produced by the 2020 storms appear to have scaled at about twice the rate suggested by the Clausius-Clapeyron relation, given that climate change has warmed the Atlantic Ocean basin by as much as 0.9 degrees Celsius.
In general, there's increasing evidence that the 'most intense convective downpours — meaning the heaviest torrential rain events from thunderstorms, specifically — are already increasing at a rate that greatly exceeds that of other types of precipitation,' Swain said.
It's a phenomenon scientists have dubbed the super-Clausius-Clapeyron rate. Researchers are still investigating the reasons it's happening.
At least one recent study, published in April, suggests the trend could be a statistical quirk caused by an increase in the frequency of thunderstorms compared with milder rainfall events. In other words, it's not that the storms themselves are defying established physics — the strongest kinds of storms are just becoming more common.
That study focused only on storms in Europe, meaning more research is needed to understand what's happening with rainfall events around the globe. Still, the authors note that rainfall rates are clearly increasing faster than expected in some cases — and that's a trend scientists should account for when making projections for the future.
At the same time, researchers have pointed to other ways climate change may be supercharging the worst precipitation events.
One recent study warns that long-lasting summer weather patterns, such as extended heat waves or lingering storms, are on the rise — and physical changes in the atmosphere, driven by global warming, may be to blame. When already heavy rainfall events stall in place, they can dump massive volumes of water on a single location, triggering life-threatening floods.
Put together, the science suggests that communities should prepare for record-breaking storms and flash flood events to continue worsening across the U.S., researchers warn.
These events have been 'significantly underestimated as a hazard in a warming climate,' Swain said in his YouTube talk. 'There's a lot of evidence right now with the most recent science … that these are precisely the kinds of events that are going to increase the most, and in fact already are, and much faster than 'ordinary' precipitation events.'
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The Hill
9 hours ago
- The Hill
The beauty industry loves argan oil. But demand, and drought, are straining Morocco and its trees
SMIMOU, Morocco (AP) — Argan oil runs through your fingers like liquid gold — hydrating, luscious, and restorative. Prized worldwide as a miracle cosmetic, it's more than that in Morocco. It's a lifeline for rural women and a byproduct of a forest slowly buckling under the weight of growing demand. To make it, women crouch over stone mills and grind down kernels. One kilogram — roughly two days of work — earns them around $3, enough for a modest foothold in an economy where opportunities are scarce. It also links them to generations past. 'We were born and raised here. These traditions come from nature, what our parents and grandparents have taught us and what we've inherited,' cooperative worker Fatma Mnir said. Long a staple in local markets, argan oil today is in luxury hair and skin care products lining drugstore aisles worldwide. But its runaway popularity is threatening argan forests, with overharvesting piled on top of drought straining trees once seen as resilient in the harshest of conditions. Hafida El Hantati, owner of one of the cooperatives that harvests the fruit and presses it for oil, said the stakes go beyond the trees, threatening cherished traditions. 'We must take care of this tree and protect it because if we lose it, we will lose everything that defines us and what we have now,' she said at the Ajddigue cooperative outside the coastal town of Essaouira. A forest out of time For centuries, argan trees have supported life in the arid hills between the Atlantic Ocean and the Atlas Mountains, feeding people and animals, holding soil in place and helping keep the desert from spreading. The spiny trees can survive in areas with less than an inch of annual rain and heat up to 50 degrees Celsius (122 Fahrenheit). They endure drought with roots that stretch as far as 115 feet (35 meters) underground. Goats climb trees, chomp their fruit, and eventually disperse seeds as part of the forest's regeneration cycle. Moroccans stir the oil into nut butters and drizzle it over tagines. Rich in vitamin E, it's lathered onto dry hair and skin to plump, moisturize and stave off damage. Some use it to calm eczema or heal chicken pox. But the forest has thinned. Trees bear fewer fruit, their branches gnarled from thirst. In many places, cultivated land has replaced them as fields of citrus and tomatoes, many grown for export, have expanded. Communities once managed forests collectively, setting rules for grazing and harvesting. Now the system is fraying, with theft routinely reported. What's wrong with the forest But a forest that covered about 5,405 square miles (14,000 square kilometers) at the turn of the century has shrunk by 40%. Scientists warn that argan trees are not invincible. 'Because argan trees acted as a green curtain protecting a large part of southern Morocco against the encroaching Sahara, their slow disappearance has become considered as an ecological disaster,' said Zoubida Charrouf, a chemist who researches argan at Université Mohammed V in Rabat. Shifting climate is a part of the problem. Fruit and flowers sprout earlier each year as rising temperatures push the seasons out of sync. Goats that help spread seeds can be destructive, too, especially if they feed on seedlings before they mature. Overgrazing has become worse as herders and fruit collectors fleeing drier regions encroach on plots long allocated to specific families. The forests also face threats from camels bred and raised by the region's wealthy. Camels stretch their necks into trees and chomp entire branches, leaving lasting damage, Charrouf said. Liquid gold, dry pockets Today, women peel, crack and press argan for oil at hundreds of cooperatives. Much makes its way through middlemen to be sold in products by companies and subsidiaries of L'Oréal, Unilever, and Estée Lauder. But workers say they earn little while watching profits flow elsewhere. Cooperatives say much of the pressure stems from climbing prices. A 1-liter bottle sells for 600 Moroccan dirhams ($60), up from 25 dirhams ($2.50) three decades ago. Products infused with argan sell for even more abroad. Cosmetics companies call argan the most expensive vegetal oil on the market. The coronavirus pandemic upended global demand and prices and many cooperatives closed. Cooperative leaders say new competitors have flooded the market just as drought has diminished how much oil can be squeezed from each fruit. Cooperatives were set up to provide women a base pay and share profits each month. But Union of Women's Argan Cooperatives President Jamila Id Bourrous said few make more than Morocco's minimum monthly wage. 'The people who sell the final product are the ones making the money,' she said. Some businesses say large multinational companies use their size to set prices and shut others out. Khadija Saye, a co-owner of Ageourde Cooperative, said there were real fears about monopoly. 'Don't compete with the poor for the one thing they live from,' she said. 'When you take their model and do it better because you have money, it's not competition, it's displacement.' One company, Olvea, controls 70% of the export market, according to data from local cooperatives. Cooperatives say few competitors can match its capacity to fill big orders for global brands. Representatives for the company did not respond to requests for comment. Mounting challenges, limited solutions On a hill overlooking the Atlantic, a government water truck weaves between rows of trees, pausing to hose saplings that have just started to sprout. The trees are a project that Morocco began in 2018, planting 39 square miles (100 square kilometers) on private lands abutting the forests. To conserve water and improve soil fertility, argan trees alternate rows with capers, a technique known as intercropping. The idea is to expand forest cover and show that argan, if properly managed, can be a viable source of income. Officials hope it will ease pressure on the overharvested commons and convince others to reinvest in the land. The trees were expected to begin producing this year but haven't during a drought. Another issue is the supply chain. 'Between the woman in the village and the final buyer, there are four intermediaries. Each takes a cut. The cooperatives can't afford to store, so they sell cheap to someone who pays upfront,' Id Bourrous, the union president, said. The government has attempted to build storage centers to help producers hold onto their goods longer and negotiate better deals. So far, cooperatives say it hasn't worked, but a new version is expected in 2026 with fewer barriers to access. Despite problems, there's money to be made. During harvest season, women walk into the forest with sacks, scanning the ground for fallen fruit. To El Hantati, the forest, once thick and humming with life, feels quieter now. Only the winds and creaking trees are audible as goats climb branches in search of remaining fruits and leaves. 'When I was young, we'd head into the forest at dawn with our food and spend the whole day gathering. The trees were green all year long,' she said. She paused, worried about the future as younger generations pursue education and opportunities in larger cities. 'I'm the last generation that lived our traditions — weddings, births, even the way we made oil. It's all fading.' Islam Aatfaoui contributed reporting. ___
Hamilton Spectator
9 hours ago
- Hamilton Spectator
The beauty industry loves argan oil. But demand, and drought, are straining Morocco and its trees
SMIMOU, Morocco (AP) — Argan oil runs through your fingers like liquid gold — hydrating, luscious, and restorative. Prized worldwide as a miracle cosmetic, it's more than that in Morocco. It's a lifeline for rural women and a byproduct of a forest slowly buckling under the weight of growing demand. To make it, women crouch over stone mills and grind down kernels. One kilogram — roughly two days of work — earns them around $3, enough for a modest foothold in an economy where opportunities are scarce. It also links them to generations past. 'We were born and raised here. These traditions come from nature, what our parents and grandparents have taught us and what we've inherited,' cooperative worker Fatma Mnir said. Long a staple in local markets, argan oil today is in luxury hair and skin care products lining drugstore aisles worldwide. But its runaway popularity is threatening argan forests, with overharvesting piled on top of drought straining trees once seen as resilient in the harshest of conditions. Hafida El Hantati, owner of one of the cooperatives that harvests the fruit and presses it for oil, said the stakes go beyond the trees, threatening cherished traditions. 'We must take care of this tree and protect it because if we lose it, we will lose everything that defines us and what we have now,' she said at the Ajddigue cooperative outside the coastal town of Essaouira. A forest out of time For centuries, argan trees have supported life in the arid hills between the Atlantic Ocean and the Atlas Mountains, feeding people and animals, holding soil in place and helping keep the desert from spreading. The spiny trees can survive in areas with less than an inch of annual rain and heat up to 50 degrees Celsius (122 Fahrenheit). They endure drought with roots that stretch as far as 115 feet (35 meters) underground. Goats climb trees, chomp their fruit, and eventually disperse seeds as part of the forest's regeneration cycle. Moroccans stir the oil into nut butters and drizzle it over tagines. Rich in vitamin E, it's lathered onto dry hair and skin to plump, moisturize and stave off damage. Some use it to calm eczema or heal chicken pox. But the forest has thinned. Trees bear fewer fruit, their branches gnarled from thirst. In many places, cultivated land has replaced them as fields of citrus and tomatoes, many grown for export, have expanded. Communities once managed forests collectively, setting rules for grazing and harvesting. Now the system is fraying, with theft routinely reported. What's wrong with the forest But a forest that covered about 5,405 square miles (14,000 square kilometers) at the turn of the century has shrunk by 40%. Scientists warn that argan trees are not invincible. 'Because argan trees acted as a green curtain protecting a large part of southern Morocco against the encroaching Sahara, their slow disappearance has become considered as an ecological disaster,' said Zoubida Charrouf, a chemist who researches argan at Université Mohammed V in Rabat. Shifting climate is a part of the problem. Fruit and flowers sprout earlier each year as rising temperatures push the seasons out of sync. Goats that help spread seeds can be destructive, too, especially if they feed on seedlings before they mature. Overgrazing has become worse as herders and fruit collectors fleeing drier regions encroach on plots long allocated to specific families. The forests also face threats from camels bred and raised by the region's wealthy. Camels stretch their necks into trees and chomp entire branches, leaving lasting damage, Charrouf said. Liquid gold, dry pockets Today, women peel, crack and press argan for oil at hundreds of cooperatives. Much makes its way through middlemen to be sold in products by companies and subsidiaries of L'Oréal, Unilever, and Estée Lauder. But workers say they earn little while watching profits flow elsewhere. Cooperatives say much of the pressure stems from climbing prices. A 1-liter bottle sells for 600 Moroccan dirhams ($60), up from 25 dirhams ($2.50) three decades ago. Products infused with argan sell for even more abroad. Cosmetics companies call argan the most expensive vegetal oil on the market. The coronavirus pandemic upended global demand and prices and many cooperatives closed. Cooperative leaders say new competitors have flooded the market just as drought has diminished how much oil can be squeezed from each fruit. Cooperatives were set up to provide women a base pay and share profits each month. But Union of Women's Argan Cooperatives President Jamila Id Bourrous said few make more than Morocco's minimum monthly wage. 'The people who sell the final product are the ones making the money,' she said. Some businesses say large multinational companies use their size to set prices and shut others out. Khadija Saye, a co-owner of Ageourde Cooperative, said there were real fears about monopoly. 'Don't compete with the poor for the one thing they live from,' she said. 'When you take their model and do it better because you have money, it's not competition, it's displacement.' One company, Olvea, controls 70% of the export market, according to data from local cooperatives. Cooperatives say few competitors can match its capacity to fill big orders for global brands. Representatives for the company did not respond to requests for comment. Mounting challenges, limited solutions On a hill overlooking the Atlantic, a government water truck weaves between rows of trees, pausing to hose saplings that have just started to sprout. The trees are a project that Morocco began in 2018, planting 39 square miles (100 square kilometers) on private lands abutting the forests. To conserve water and improve soil fertility, argan trees alternate rows with capers, a technique known as intercropping. The idea is to expand forest cover and show that argan, if properly managed, can be a viable source of income. Officials hope it will ease pressure on the overharvested commons and convince others to reinvest in the land. The trees were expected to begin producing this year but haven't during a drought. Another issue is the supply chain. 'Between the woman in the village and the final buyer, there are four intermediaries. Each takes a cut. The cooperatives can't afford to store, so they sell cheap to someone who pays upfront,' Id Bourrous, the union president, said. The government has attempted to build storage centers to help producers hold onto their goods longer and negotiate better deals. So far, cooperatives say it hasn't worked, but a new version is expected in 2026 with fewer barriers to access. Despite problems, there's money to be made. During harvest season, women walk into the forest with sacks, scanning the ground for fallen fruit. To El Hantati, the forest, once thick and humming with life, feels quieter now. Only the winds and creaking trees are audible as goats climb branches in search of remaining fruits and leaves. 'When I was young, we'd head into the forest at dawn with our food and spend the whole day gathering. The trees were green all year long,' she said. She paused, worried about the future as younger generations pursue education and opportunities in larger cities. 'I'm the last generation that lived our traditions — weddings, births, even the way we made oil. It's all fading.' ___ Islam Aatfaoui contributed reporting. ___ The Associated Press' climate and environmental coverage receives financial support from multiple private foundations. AP is solely responsible for all content. Find AP's standards for working with philanthropies, a list of supporters and funded coverage areas at .
Hamilton Spectator
a day ago
- Hamilton Spectator
Sizzling temperatures expected again Monday
Monday is day two in the latest heat wave expected to keep the city sizzling. The city's medical officer of health issued the heat warning only 12 hours after cancelling the last one. The next two days will bring us daytime highs between 30 and 33 degrees Celsius, Environment Canada says on Monday morning. With humidity, it could feel like 43 C. The heat event is expected to end by Wednesday, with the hottest days Monday and Tuesday, the national weather service says. Residents are urged to be cautious and to keep an eye on older adults, those living alone and others who might be at risk of heat illness, the service adds. Heat exhaustion signs to watch for include: headache, nausea, dizziness, thirst, dark urine and intense fatigue. Stop your activity and drink water. In Hamilton, the city and some community agencies are responding to the heat by offering 'cool places' to go during all stages of a heat event. These locations can be identified by a 'Cool Down Here' sign at the entrance. As part of the heat response plan, regularly scheduled Open Swims at all City of Hamilton indoor and outdoor pools will be free of charge. There are many spray pads, additional cool places across Hamilton. Monday's daytime temperatures are likely to by 33 C, feeling like 42. Overnight, it will drop to 21 and Tuesday's daytime high will reach 32 but feel like 41. Clouds will move in Tuesday, giving us a risk of thunderstorm in the afternoon. Wednesday's high will be 29 and Thursday 25. Heat Warnings stay in effect until they are cancelled or escalated to an Extended Heat Warning by the MOH. Error! Sorry, there was an error processing your request. There was a problem with the recaptcha. Please try again. You may unsubscribe at any time. By signing up, you agree to our terms of use and privacy policy . This site is protected by reCAPTCHA and the Google privacy policy and terms of service apply. Want more of the latest from us? Sign up for more at our newsletter page .
