Latest news with #sinkingCities
Forbes
14-05-2025
- Science
- Forbes
The 28 Biggest U.S. Cities Are Sinking, Satellites Say. Here's Why
A new study using recent satellite data finds that all cities in the United States with populations ... More of more than 600,000 are sinking — and Houston, Texas, the most. America's most populous cities are finding themselves on increasingly unstable ground, with data from satellites revealing that 28 major U.S. cities are sinking, according to new research. About 34 million people are potentially affected, about 12% of the population. The culprit is the extraction of water from underground aquifers, many of which crumble and compact in the ground. The research, published in Nature Cities, revealed that metropolises, including New York, Dallas-Fort Worth, Houston and Seattle have urban areas that are sinking by between two and 10 millimeters per year. At least 20 percent of the urban area in each of the 28 cities is sinking, the data suggests, though the problem is much more serious in most affected cities, with 25 of the 28 cities having at least 65% of the urban area sinking. A new study using recent satellite data finds that all cities in the United States with populations ... More of more than 600,000 are sinking to one degree or another. The 28 cities are Austin, Boston, Charlotte, Chicago, Columbus, Dallas, Denver, Detroit, El Paso, Fort Worth, Houston, Indianapolis, Jacksonville, Las Vegas, Los Angeles, Memphis, Nashville, New York, Oklahoma City, Philadelphia, Phoenix, Portland, San Antonio, San Diego, San Francisco, San Jose, Seattle and Washington, D.C. It's putting more than 29,000 buildings at risk in high and very high damage risk areas, say the authors, with even a slight shift of the land downward threatening the structural integrity of buildings, roads, bridges and dams. The research is based upon radar measurements from the Sentinel-1 constellation of satellites. The research is based upon radar measurements from the Sentinel-1 constellation of satellites that use their Synthetic Aperture Radar instruments to measure land elevation changes in all U.S. cities with populations exceeding 600,000. The data was used to create high-resolution maps of subsidence in the 28 most populous U.S. cities. The same technology is often used to measure changes in sea ice, oil spills and land-use change. "A lot of small changes will build up over time, magnifying weak spots within urban systems and heighten flood risks," said Leonard Ohenhen, lead author and a former graduate student at Virginia Tech's Earth Observation and Innovation Lab. The fastest-sinking city is Houston, where more than 12% of its area subsides more than 10 millimeters (about 1/5 inch) per year and some localized spots up to 5 centimeters (2 inches) per year. Two other Texas cities, Fort Worth and Dallas, are not far behind. Some localized fast-sinking zones in other places include areas around New York's LaGuardia Airport and parts of Las Vegas, Washington, D.C. and San Francisco. There is a similar localized impact in New York, Las Vegas and Washington, D.C. However, New York, Chicago, Seattle, Denver [and five other cities] are sinking by the least amount, at about two millimeters per year. Much of New York City is slowly sinking, with some hot spots, especially around La Guardia Airport, ... More and parts of Jamaica Bay and Staten Island. In terms of population density, eight cities (New York, Chicago, Los Angeles, Phoenix, Houston, Philadelphia, San Antonio and Dallas) account for more than 60% of the people living on sinking land. These same eight cities have had more than 90 significant floods since 2000, state the authors, with lowering topography as one of the causes. The cause, according to the researchers, in 80% of cases is the extraction of groundwater, with fast-growing cities rapidly expanding their extraction of freshwater from aquifers faster than they can be replenished. In Texas, the problem is exacerbated by the pumping of oil and gas, the paper says. 'As cities continue to grow, we will see more cities expand into subsiding regions,' said Ohenhen. 'Over time, this subsidence can produce stresses on infrastructure that will go past their safety limit.' The authors suggest managing groundwater extraction more carefully, using more resilient buildings and infrastructure, and monitoring more. 'As opposed to just saying it's a problem, we can respond, address, mitigate, adapt,' said Ohenhen. 'We have to move to solutions.' In 2023, scientists discovered that New York City's over one million buildings — and relentless construction — may be causing the city to subside, exacerbating the risk of future flooding. Wishing you clear skies and wide eyes.
Yahoo
11-05-2025
- Science
- Yahoo
Scientists sound alarm over massive underwater force threatening to accelerate city collapse: 'Potentially double or triple the effects'
Rising sea levels and subsiding shorelines are putting New Zealand's coastal communities at risk. A new study revealed that human activities heighten and expedite the risks of sinking cities. As Forbes reported, a group of New Zealand researchers studied how the island's cities and shorelines are sinking. This is concerning because sinking cities may be affected by rising sea levels sooner than previously anticipated. In New Zealand and globally, sea levels are rising due to our warming climate and melting ice in polar regions. Meanwhile, localized instances of human activity, such as groundwater extraction, land reclamation, and dredging, are causing coastal lands to sink. Kyoto University researcher Jesse Kearse said these activities can "potentially double or triple the effects of sea-level rise in certain places." The researchers determined that coastal infrastructure is at risk because of this sinking effect and rising sea levels. In their study, they used satellite-based mapping and radar images to assess the physical properties of surfaces and measure ground deformation. Focusing on vertical land movement at urban coastal strips between 2018 and 2021, they observed coastal strips decreasing in all of New Zealand's major population centers. Some areas are experiencing subsidence rates of over 15 millimeters per year. This revelation is significant because billions of people live near coastlines. No coastal city, in New Zealand or elsewhere, is immune to rising sea levels. With supercharged weather events becoming more common as our climate warms, people living along the coast face considerable danger. This study also stands out because it highlights humans' impacts on at-risk coastlines. The researchers noted that areas of reclaimed land in New Zealand are particularly vulnerable to the land's stability. What would you do if natural disasters were threatening your home? Move somewhere else Reinforce my home Nothing This is happening already Click your choice to see results and speak your mind. Land reclamation involves filling water-submerged areas with soil, rock, or other materials to create new land where water once flowed. The researchers concluded by pointing out many unanswered questions regarding subsidence rates and how long they will persist. They also warned about the risks of future development in coastal areas due to vertical land motion patterns. Research studies like this one raise public awareness about coastal community risks and the threats of rising sea levels, especially when extreme storms hit. Fortunately, governments and businesses are working on technologies to adapt and plan ahead. For example, innovators use predictive artificial intelligence and smart reefs to protect residents from floods. Architecture firms have designed floating homes as practical solutions for people living in flood-prone areas. Meanwhile, officials have developed plans to protect coastal lands by planting mangroves and adding sand piles. If you live along the coast, there are steps you can take to protect yourself and your home. Preparing for hurricanes and floods is crucial, so keep a go bag packed if you need to evacuate. To prepare for future power outages, you can install solar panels or sign up for a community solar program. (Solar is also a type of clean energy. In other words, the photovoltaic panels don't generate any troublesome heat-trapping pollution when turning sunlight into power.) Hurricane-proofing your house by raising it and installing a custom seawall can help as well as reinforcing your home with durable materials to boost its resilience and give you peace of mind. Join our free newsletter for good news and useful tips, and don't miss this cool list of easy ways to help yourself while helping the planet.
