Climate change is coming for coastlines, from ancient cities to modern California: study
Climate change-induced seawater intrusions are hastening the collapse of buildings in the ancient Egyptian port city of Alexandria — posing threats similar to those challenging coastal California, a new study has found.
While such breakdowns were once a rare occurrence in Alexandria, these events have surged from approximately one to about 40 per year over the past decades, according to the study, published on Thursday in Earth's Future.
'For centuries, Alexandria's structures stood as marvels of resilient engineering, enduring earthquakes, storm surges, tsunamis and more,' lead author Sara Fouad, a landscape architect at the Technical University of Munich, said in a statement.
'But now, rising seas and intensifying storms — fueled by climate change — are undoing in decades what took millennia of human ingenuity to create,' Fouad added.
The researchers used geographic information system technology to create digital maps focusing on six districts across the city's historic and densely populated urban area. Details included in the maps pertain to each structure's composition, size and foundation depth — information collected from site visits and reports from 2001 through 2021.
The researchers then combined satellite imagery with historical maps from 1887, 1959 and 2001 to measure shoreline movement and to understand how the 50-mile coastline shifted inland in recent decades.
After calculating the rate of shoreline retreat over the past century, the scientists determined that the diminishing coastline was raising groundwater levels — and hurling that water into the foundations of seaside structures.
The researchers also analyzed what they described as chemical 'fingerprints' in soil samples, which included specific isotopes that were indicative of soil strength and stability versus erosion.
'Our isotope analysis revealed that buildings are collapsing from the bottom up, as seawater intrusion erodes foundations and weakens the soil,' co-author Ibrahim Saleh, a soil radiation scientist at Alexandria University, said in a statement. 'It isn't the buildings themselves, but the ground underneath them that's being affected.'
These findings also demonstrate that coastal structures are under threat of collapse 'even without directly encroaching on the seawater,' added corresponding author Essam Heggy, a water scientist at the University of Southern California's Viterbi School of Engineering.
Like Alexandria, the researchers warned, California's coastal cities are facing increased danger from saltwater intrusion, which could weaken infrastructure, degrade water supplies and drive up the cost of living there as well.
Recent studies have shown that parts of the Golden State, including the San Francisco Bay Area, the Central Valley and coastal Southern California, are sinking, the authors noted. And what might appear to be minor elevation changes could cause a tremendous rise in the flood and seawater intrusion risks, according to the scientists.
'Our study challenges the common misconception that we'll only need to worry when sea levels rise by a meter,' Heggy said in a statement.
'However, what we're showing here is that coastlines globally, especially Mediterranean coastlines similar to California's, are already changing and causing building collapses at an unprecedented rate,' he added.
In addition to sounding the alarm on these new coastal erosion threats, Heggy and his colleagues also proposed a nature-based solution in their study.
They raised the idea of creating sand dunes and vegetation barriers along shorelines to hinder seawater encroachment and thereby prevent groundwater from reaching building foundations.
Such an approach, they argued, could be applied to densely-populated coastal cities around the world, in a sustainable and cost-effective manner.
Without taking such action, coastal residents could be left with a loss that 'extends far beyond bricks and mortar,' Heggy noted.
'We are witnessing the gradual disappearance of historic coastal cities, with Alexandria sounding the alarm,' he added. 'What once seemed like distant climate risks are now a present reality.'
Hashtags
Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Yahoo
5 days ago
- Yahoo
Scientists reveal futuristic farming technique that may solve two global problems at once: 'Can revolutionize food production'
A team of scientists in Singapore has uncovered powerful new evidence that vertical farming — growing food in stacked and often indoor, controlled environments — could radically change how we feed the planet while also helping restore it. The study, led by Dr. Vanesa Calvo-Baltanás and published in the journal PNAS Nexus, examined how six food groups — crops, algae, mushrooms, insects, fish, and cultivated meat — performed in the controlled environmental agriculture of a 10-layer vertical farming system. The results were summarized in a report from the Technical University of Munich, shared by The foods not only dramatically outperformed traditional crop yields, but they also came with significantly lower environmental costs. For example, mushrooms and insects grown in vertical farms could produce up to 6,000 times more protein per acre than traditional farming. They also processed agricultural waste into edible, nutritious food, required very little light, and helped close resource loops that typically lead to pollution or emissions, which have damaging long-term effects on human health. With the climate crisis escalating and the world population projected to be near 10 billion by 2050, according to the United Nations, sustainable food systems are no longer optional. A study published in the journal Nature Food predicted a possible increase in food demand of around 60% by mid-century. Current agricultural methods are vulnerable to rising temperatures, extreme weather, and land degradation, and they consume massive amounts of water, land, and dirty fuels. Vertical farming provides a way to cut down on land use, eliminate pesticides, and produce food locally year-round, even in dense cities. In vertical farming, "food can be grown close to consumers, independent of the weather and using space efficiently," Calvo-Baltanás said in the university report, per In just one acre of vertical space, a greenhouse can yield what would typically require 40 acres of farmland, according to Eden Green Technology. And because it can reduce the need for long-haul shipping of food, it can cut down on transportation pollution and food waste. What is the biggest reason you don't grow food at home? Not enough time Not enough space It seems too hard I have a garden already Click your choice to see results and speak your mind. The technology isn't without hurdles. High energy demands and social acceptance remain key barriers to scaling up. But the study's authors say policy incentives, public support, and innovations in clean energy could unlock the full potential of this system. "Controlled environment agriculture can revolutionize food production," said Dr. Calvo-Baltanás. "However, technological advances, interdisciplinary research to tackle energy issues, policy incentives, and public engagement are needed to realize its full potential." As part of the Proteins4Singapore project, the researchers hope to help meet 30% of Singapore's nutritional needs locally by 2030 — a model other cities could soon follow if successful. Some innovators are already proving how vertical farms can thrive in urban settings. And, as the research shows, vertical farming may not just feed the future, but also help heal the planet along the way. Join our free newsletter for weekly updates on the latest innovations improving our lives and shaping our future, and don't miss this cool list of easy ways to help yourself while helping the planet.
Yahoo
6 days ago
- Yahoo
Scientists recreate lost recipes for a 5,000-year-old Egyptian blue dye
For being the world's oldest known synthetic pigment, the original recipes for Egyptian blue remain a mystery. The approximately 5,000-year-old dye wasn't a single color, but instead encompassed a range of hues, from deep blues to duller grays and greens. Artisans first crafted Egyptian blue during the Fourth Dynasty (roughly 2613 to 2494 BCE) from recipes reliant on calcium-copper silicate. These techniques were later adopted by Romans in lieu of more expensive materials like lapis lazuli and turquoise. But the additional ingredient lists were lost to history by the time of the Renaissance. This is particularly frustrating not just for preservation efforts, but because of Egyptian blue's unique biological, magnetic, and optical properties. Unlike other pigments, the Egyptian blue emits near-infrared light wavelengths that are unseen by the human eye, making it a promising tool for anticounterfeiting efforts, fingerprinting, and even high-temperature superconductors. But after studying ancient materials and manufacturing methods, a team led by Washington State University (WSU) researchers in collaboration with the Smithsonian's Conservation Institute and the Carnegie Museum of Natural History have created not just one historically accurate Egyptian blue, but 12 of them. While the results are detailed in a study published in npj Heritage Science, first author and WSU materials engineer John McCloy said the project began as something much more casual. 'It started out just as something that was fun to do because they asked us to produce some materials to put on display at the museum, but there's a lot of interest in the material,' he said in a statement. McCloy and colleagues first consulted both a mineralogist and an Egyptologist to create a list of potential materials to develop the pigments, including mixtures of calcium, copper, silicon dioxide, and sodium carbonate. From there, they varied the ingredient proportions before heating them anywhere from 1 to 11 hours at around 1,832 degrees Fahrenheit—temperatures achievable by ancient Egyptian artisans. Once the mixtures cooled at varying rates, the team analyzed each final result using techniques including X-ray diffraction, electron beam X-ray microanalysis, and X-ray nano-computed tomography. Finally, they compared these samples to a pair of Egyptian artifacts including a piece of cartonnage—a papier-mâché-like material used for items like funerary masks. 'One of the things that we saw was that with just small differences in the process, you got very different results,' McCloy said. For example, cooling rates played an important role in influencing the end color. Slower cooling times offered deeper blues, while quicker cooling produced pale gray and green mixtures. Despite this, the bluest of the 12 variants only required about 50 percent of their ingredients to exhibit blue hues. McCloy's team also confirmed that cuprorivaite—the naturally occurring mineral equivalent to Egyptian blue—remains the primary color influence in each hue. Despite the presence of other components, Egyptian blue appears as a uniform color after the cuprorivaite becomes encased in colorless particles such as silicate during the heating process. 'It doesn't matter what the rest of it is, which was really quite surprising to us. You can see that every single pigment particle has a bunch of stuff in it—it's not uniform by any means,' he added. The results go beyond establishing Egyptian blue recipes that largely mirror ancient examples. McCloy and colleagues hope that these initial 12 variants will be used in conservation work to restore historic relics as accurately and vividly as possible.
Yahoo
6 days ago
- Yahoo
If you want to protect your brain, this diet beats the Mediterranean diet, new study suggests
New evidence finds that the MIND diet lives up to its name, even when it is started later in life. Middle-aged and older participants in a large, long-term study were less likely to develop Alzheimer's disease or other types of dementia if they followed a diet filled with green, leafy vegetables, olive oil, whole grains and lots of berries, according to a report presented Monday at the annual meeting of the American Society for Nutrition. Researchers from University of Hawaii at Mānoa and the University of Southern California discovered that adhering to the MIND diet, which combines the Mediterranean diet with the blood-pressure-lowering DASH diet, results in a stronger and more consistent reduction in dementia risk than what is seen with other healthy diets. The new findings suggest it's never too late to switch to a healthy diet, said the study's lead author, Song-Yi Park, an associate professor at the University of Hawaii at Mānoa. 'It shows that sticking to a healthy diet, as well as improving the health of the person's diet over time, is very important for older adults who want to prevent dementia.' While all the Mediterranean-related diets appear to be good for the brain, the MIND dietary pattern was specifically designed for brain health. 'One important difference is that MIND includes berries, which have been linked to brain health,' Park said. The MIND diet, or Mediterranean-DASH Intervention for Neurodegenerative Delay, scores individual foods based on how protective they are and how much is eaten. Berries — especially strawberries and blueberries — for example, get a score of 1 if two or more servings are consumed per week. The score drops to 0.5 if just one serving per week is consumed and a score of 0 if none are. A person's individual diet gets an overall rating by adding up the scores for individual foods. The higher the overall score, the better it's for the person's brain. Park and her colleagues turned to data from nearly 93,000 U.S. adults who had provided information about what they ate as part of a research project known as The Multiethnic Cohort to get a closer look at how diet influenced the risk of developing dementia. The Multiethnic Cohort was started in the early 1990s through a joint effort of the University of Hawaii Cancer Center and the USC Norris Comprehensive Cancer Center. The men and women enrolled in the study came from five ethnic/racial populations: Japanese Americans, Native Hawaiians, Black Americans, Latinos and whites. At the outset, the 215,000 participants were ages 45 to 75. When data for the new study was analyzed, more than 21,000 participants had developed Alzheimer's or a related dementia. At the beginning of the study, people who scored higher for adherence to MIND had a 9% lower risk of developing dementia. The amount of reduction varied among the racial groups in the new analysis. Greater risk reduction, 13%, was seen in participants who identified as Black, Latino or white. Participants who improved their adherence to MIND over the 10-year period had a 25% lower risk of dementia compared with those whose adherence declined, and that trend was seen across all age and racial groups. Some suggestions for reaching the optimal score for the MIND diet, according to a 2015 study: Leafy green vegetables, such as kale, spinach, broccoli, bok choy and mustard: six or more servings per week Other vegetables: one serving per day Nuts, such as almonds, walnuts or pistachios: five or more servings per week Cheese: less than one per week Whole grains: three or more per day Fish (not fried): one or more servings per week Red meat: less than one serving per week Fast fried foods: less than one per week Pastries and sweets: less than five servings per week Park cautioned that like all observational studies, the new research reports an association and doesn't prove that the diet prevents dementia. It is a high-quality study, Dr. Walter Willett, a professor of epidemiology and nutrition at the Harvard T.H. Chan School of Public Health and a professor of medicine at the Harvard Medical School, said in an email. 'It adds to the evidence that a Mediterranean-type diet has important benefits for reducing the risk of dementia,' said Willett, who wasn't involved in the research. 'The differences between groups defined by race/ethnicity may well be due to random variation, so at this time it's reasonable to assume that this healthy dietary pattern has benefits for all groups." When it comes to leafy green vegetables, it's probably best to consume a variety rather than a single type, Willett said. 'In particular, spinach is good in many ways, but has high oxalate content and high intake of spinach can cause kidney stones,' he said. In general, the MIND diet is in line with the principles of the two diets it's built from, said Dr. Yian Gu, an associate professor of neurological sciences at the Columbia University Irving Medical Center. 'Each of those diets has unique characteristics,' she said. The Mediterranean diet emphasizes multiple daily servings of fruits and vegetables, along with whole grains, legumes, olive oil, seafood, and nuts and seeds, such as chia, flax, pumpkin and sesame. DASH, or Dietary Approaches to Stop Hypertension, is meant to prevent hypertension, so it emphasizes low salt, which isn't a major component in the Mediterranean diet. The MIND diet is easy to follow, Gu said, encouraging people to pick the green, leafy vegetables they prefer. What's important is to increase the diversity of vegetables. Another benefit of Mediterranean-type diets: They are helpful with other types of chronic disease, including heart disease and cancer, she said. This article was originally published on
