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.
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Patients reporting these symptoms should be monitored regularly for neurologic changes. In clinical history-taking, ask specifically about vivid dreams, violent movements during sleep, or vocalizations. Though often dismissed as quirky or anecdotal, recurring incidents should raise red flags. Constipation Parkinson's doesn't begin with tremors or slowed movement. Nonmotor symptoms, especially gastrointestinal issues, often appear first. The disease affects the autonomic nervous system, including the enteric nervous system that regulates bowel motility. There is evidence that pathological changes — such as alpha-synuclein accumulation — begin in the gut and olfactory bulb before affecting the brain, aligning with the Braak hypothesis. These protein aggregates can cause constipation or olfactory dysfunction long before motor symptoms emerge. Studies suggest chronic constipation can precede a Parkinson's diagnosis by 10-20 years. Up to 75% of patients with Parkinson's experience it. While constipation alone is nonspecific, it gains significance when combined with other prodromal signs. Constipation should raise concern in these contexts: Persistent, unexplained symptoms. Co-occurrence with other early signs such as: Loss of smell (hyposmia). REM sleep behavior disorder. Depressed mood. Fatigue or lack of motivation. Family history of Parkinson's. Olfactory Dysfunction Loss of smell, either partial (hyposmia) or total (anosmia), is another early and often unnoticed sign. Patients may have difficulty detecting even strong odors like coffee, bananas, or pickles. In Parkinson's, misfolded alpha-synuclein protein aggregates disrupt brain regions, including those responsible for olfaction. These changes may impair neuron function and contribute to early sensory loss. Animal studies suggest alpha-synuclein may behave like a prion — spreading through neural pathways. Trials are ongoing to determine whether monoclonal antibodies such as prasinezumab could help degrade these protein aggregates. Micrographia As Parkinson's disrupts dopamine pathways, it impairs fine motor control. Writing — a highly complex motor task — often becomes affected. Reduced movement amplitude can lead to smaller, cramped handwriting known as micrographia. Micrographia is a typical, though not universal, early motor sign and may precede other motor symptoms. It often appears alongside other signs like a softer, monotone voice or reduced arm swing while walking — both early signs of extrapyramidal dysfunction. Classic Motor Signs: TRAP Parkinson's is commonly associated with: Tremor : A resting tremor, typically 4-8 Hz, which diminishes with movement (unlike intention tremor). : A resting tremor, typically 4-8 Hz, which diminishes with movement (unlike intention tremor). Rigidity : Muscle stiffness is often described as 'cogwheel rigidity' due to a ratcheting resistance during passive limb extension. : Muscle stiffness is often described as 'cogwheel rigidity' due to a ratcheting resistance during passive limb extension. Akinesia/bradykinesia : Slowness or poverty of movement, including 'freezing' episodes that require verbal cues to initiate or stop movement. : Slowness or poverty of movement, including 'freezing' episodes that require verbal cues to initiate or stop movement. Postural instability: Impaired balance and increased risk of falls, not due to cerebellar, visual, or vestibular dysfunction. Postural instability is now recognized as a cardinal sign in the TRAP framework. Damage to extrapyramidal reflexes means patients may be unable to catch themselves when off balance. Additional Early Signs Depression and anxiety : Often overlooked or misdiagnosed as primary psychiatric conditions. : Often overlooked or misdiagnosed as primary psychiatric conditions. Reduced facial expression (hypomimia) : 'Masked' appearance due to reduced facial muscle movement. : 'Masked' appearance due to reduced facial muscle movement. Diffuse pain : Especially in the shoulders, back, or arms, sometimes preceding motor signs. : Especially in the shoulders, back, or arms, sometimes preceding motor signs. Fatigue : Persistent lack of energy not relieved by rest. : Persistent lack of energy not relieved by rest. Reduced arm swing: Subtle early sign of movement asymmetry. When to Refer for Neurological Evaluation None of these symptoms alone confirm Parkinson's disease, as many are nonspecific or seen in other conditions. 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Common Early and Prodromal Parkinson's Symptoms Symptom Description Frequency Lead Time Before Diagnosis Olfactory dysfunction (hyposmia) Reduced sense of smell; often the first sign, typically unnoticed Very common 5-15 years RBD Acting out dreams (eg, shouting, punching, or kicking) Common 10-15 years Depression, anxiety Mood disturbance, social withdrawal, loss of interest Common 5-10 years Constipation Reduced bowel motility; often chronic Common 10-20 years Pain (shoulders, back, or limbs) Diffuse musculoskeletal pain Common Can occur early Fatigue Chronic low energy not improved by sleep Moderate-common Years before diagnosis TRAP Classic cardinal signs (TRAP), often asymmetric at onset Very common Early symptom Micrographia Small, cramped handwriting Common Early symptom Hypomimia Mask-like facial expression Common Early symptom Reduced arm swing Asymmetry in arm movement while walking Common Early symptom RBD = rapid eye movement sleep behavior disorder; TRAP = tremor, rigidity, akinesia, and postural instability Identifying these signs early and recognizing meaningful combinations — not isolated symptoms — can help clinicians initiate earlier referral and intervention, potentially altering the disease trajectory.
