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Faster alerts for California megaquakes: Early-warning system gets major upgrade

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Faster alerts for California megaquakes: Early-warning system gets major upgrade

California’s earthquake early-warning system is getting a seismic upgrade, one that will allow residents to receive more timely alerts about shaking from an incoming megaquake.

The upgrade, also available in Oregon and Washington, will provide features important for warnings about the “Big One.”

The improvements could mean that, depending on where they are and where the quake begins, Californians would receive an earlier, more accurate estimate of magnitude before the earth starts shaking — say from a magnitude 7.8 earthquake that begins on the San Andreas fault near the Mexican border and ruptures the fault toward Los Angeles County.

The upgrade also would improve warnings for the Pacific Northwest and California’s North Coast, which are threatened by tsunamis from quakes along the Cascadia subduction zone.

The U.S. Geological Survey and its nonprofit partner EarthScope announced the upgraded system Wednesday.

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For the most powerful earthquakes, the improvements “become very, very critical in helping us get to the answer quicker — in terms of how big that event is,” said Robert de Groot, one of the operations team leaders of the USGS’ ShakeAlert System.

For smaller earthquakes, the older system worked “perfectly fine,” De Groot said. But with larger quakes, the magnitude could be underestimated for quite some time, robbing residents of crucial information in the seconds before they feel the most destructive shaking.

Let’s say an earthquake on the southern San Andreas fault that starts near the Mexican border ends up being a magnitude 8, but the earliest estimate says it’s a magnitude 6.5. The longer that underestimate is broadcasting to phones, the less likely people are to take appropriate action.

“People would react differently — much differently — than if you said it was a magnitude 8,” said David Mencin, vice president of data services for EarthScope, a nonprofit funded by the National Science Foundation, USGS and NASA that’s supplying data for the improved early-warning system.

“The largest, most destructive earthquakes are the ones that we’re really worried about,” Mencin said. “This fixes the problem of underestimating those magnitudes, which is critical.”

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One of the most famous underestimations came in 2011 with the epic magnitude 9.1 earthquake that triggered a devastating tsunami off the eastern coast of Japan, leaving roughly 18,000 dead. An initial estimate put the quake’s magnitude at 7.9, meaning the actual earthquake was an astonishing 63 times stronger in terms of energy released.

That underestimation led to a misjudgment of tsunami heights — with some of the first detailed alerts erroneously estimating the tsunami would be lower than protective sea walls. And when communications were cut off, a false sense of security settled in, with many people never receiving accurate evacuation alerts.

Had Japan used GPS data, a more accurate magnitude of the quake could’ve been generated far more quickly, Mencin said.

The USGS’ West Coast earthquake early-warning system has long relied on hundreds of seismic sensors embedded in the ground. But there is only so much shaking they can detect in a short time.

“Seismometers tend to get overwhelmed for earthquakes that are magnitude 7 and greater. They can begin to get ‘saturated,’” Mencin said. During particularly intense shaking, the seismometers — basically objects on a spring — start to hit the wall of the instrument, and so the seismic signal is “clipped” and can’t quickly calculate magnitudes above a certain threshold.

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Coming to the rescue now are hundreds of GPS sensors on Earth’s surface and run by EarthScope. Most of the time, these sensors track very slow movement, on the order of millimeters or less per year. That can illustrate subtle tectonic plate action between major earthquakes, illustrating how the Pacific plate, where L.A. is located, is nudging northwest relative to the North American plate, where the Mojave Desert is located.

But in a major earthquake, there is considerable, permanent movement of the ground, where one piece of land jolts away from the other, moving yards in seconds. In the great San Francisco earthquake of 1906, land on one side of the San Andreas fault generally jammed 8.5 feet past the other, De Groot said.

And in the last great southern San Andreas earthquake — rupturing the fault in 1857 between Monterey and San Bernardino counties — land on one side of the fault generally lurched 10 feet relative to the other side. Both the 1857 and 1906 earthquakes were somewhere around magnitude 7.8.

In the largest of the Ridgecrest earthquakes in 2019, there were about 2 feet of fault offset for the magnitude 7.1 quake, De Groot said.

The first calculation of the earthquake early-warning system will still rely on seismic sensors, which measure ground velocity and acceleration, De Groot said. Then, as a quake continues to rupture along a fault, GPS sensors will measure the distance a block of land has moved.

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“What GPS allows us to do is to get a handle on how big that earthquake is getting — or could be — sooner,” De Groot said. That means the early-warning system could realize a quake was a magnitude 7, or higher, a few seconds earlier than before.

It’s important to know that an earthquake’s magnitude doesn’t appear instantly. Quakes rupture on a fault at the speed of sound through rock, which is slower than the light speed of today’s telecommunications systems. This is the principle that allows people farther away from the start of an earthquake to get seconds of advance warning of the worst shaking to come.

On the San Andreas fault, an earthquake that begins rupturing at the Salton Sea and ends at Mt. San Gorgonio, roughly 80 miles away, would produce a magnitude 7.3 earthquake.

A rupture of the San Andreas fault between the Salton Sea and Mt. San Gorgonio could produce a magnitude 7.3 quake.

(Angelica Quintero / Los Angeles Times)

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But one that ruptures the entire 340-mile length of the southern San Andreas, ending in Monterey County, would create a magnitude 8.2 earthquake and produce shaking over a much wider swath of Southern and Central California.

A map shows a potential magnitude 8.2 quake.

A rupture of the entire 340-mile length of the southern San Andreas fault between Monterey County and the Salton Sea would produce a magnitude 8.2 earthquake.

(Angelica Quintero / Los Angeles Times)

“As the earthquake grows in size, it’ll be able to help update that magnitude more quickly and with more accuracy,” De Groot said of the GPS data, which will spread the early warnings to a larger region. “By adding in the [GPS] data, you actually get a handle on how big the earthquake really is sooner.”

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The net result will “translate into longer warning times for people who could potentially get alerts on their phones,” De Groot said. That would give people more time to take action, such as surgeons and dentists moving sharp tools from near patients, allowing trains to slow to reduce the risk of derailment, opening firehouse doors before they can be jammed shut and giving the public time to drop, cover and hold on.

Depending on where people are, some may not get a warning before they feel the first shaking, which is known as the “P wave.” But the goal is to give a warning before the most damaging shaking occurs — the “S wave” — which comes later.

“What we really want to get people to know about is getting the alert before the strongest shaking,” De Groot said.

By the end of 2025, the USGS’ ShakeAlert — which is about 90% complete — is expected to have 1,675 seismic sensing stations. EarthScope says an additional 1,000 GPS stations run by the nonprofit are contributing data to the system.

EarthScope, the nation’s primary seismological and geodetic data facility, was recently formed as the merger of UNAVCO, which held an archive for GPS data, and IRIS, which held a seismic data archive.

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The earthquake early-warning system has become more popular in recent years as people get more accustomed to the alerts. In February’s widely felt magnitude-4.6 earthquake in Malibu, some felt left out when they didn’t receive an early warning.

The alerts can be received by downloading the free MyShake app on iOS and Android. Android users are automatically subscribed to Android Earthquake Alerts. Those systems are set to sound an alarm when an earthquake is estimated to be of magnitude 4.5 or higher and the expected shaking intensity at the user’s cellphone location is expected to be at least “weak” — level 3 on the Modified Mercalli Intensity Scale, where it’s felt quite noticeably by people indoors and may rock standing motor vehicles slightly or feel like a truck is passing by.

Earthquakes of greater strength — magnitude 5 and above — will send users a wireless emergency alert, similar to an Amber Alert, if they’re in a location expected to get at least “light” shaking intensity. That’s level 4 on the Modified Mercalli Intensity Scale — shaking intensity enough to rattle dishes, windows and doors, and can feel like a heavy truck striking a building.

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Cluster of farmworkers diagnosed with rare animal-borne disease in Ventura County

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Cluster of farmworkers diagnosed with rare animal-borne disease in Ventura County

A cluster of workers at Ventura County berry farms have been diagnosed with a rare disease often transmitted through sick animals’ urine, according to a public health advisory distributed to local doctors by county health officials Tuesday.

The bacterial infection, leptospirosis, has resulted in severe symptoms for some workers, including meningitis, an inflammation of the brain lining and spinal cord. Symptoms for mild cases included headaches and fevers.

The disease, which can be fatal, rarely spreads from human to human, according to the U.S. Centers for Disease Control and Prevention.

Ventura County Public Health has not given an official case count but said it had not identified any cases outside of the agriculture sector. The county’s agriculture commissioner was aware of 18 cases, the Ventura County Star reported.

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The health department said it was first contacted by a local physician in October, who reported an unusual trend in symptoms among hospital patients.

After launching an investigation, the department identified leptospirosis as a probable cause of the illness and found most patients worked on caneberry farms that utilize hoop houses — greenhouse structures to shelter the crops.

As the investigation to identify any additional cases and the exact sources of exposure continues, Ventura County Public Health has asked healthcare providers to consider a leptospirosis diagnosis for sick agricultural workers, particularly berry harvesters.

Rodents are a common source and transmitter of disease, though other mammals — including livestock, cats and dogs — can transmit it as well.

The disease is spread through bodily fluids, such as urine, and is often contracted through cuts and abrasions that contact contaminated water and soil, where the bacteria can survive for months.

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Humans can also contract the illness through contaminated food; however, the county health agency has found no known health risks to the general public, including through the contact or consumption of caneberries such as raspberries and blackberries.

Symptom onset typically occurs between two and 30 days after exposure, and symptoms can last for months if untreated, according to the CDC.

The illness often begins with mild symptoms, with fevers, chills, vomiting and headaches. Some cases can then enter a second, more severe phase that can result in kidney or liver failure.

Ventura County Public Health recommends agriculture and berry harvesters regularly rinse any cuts with soap and water and cover them with bandages. They also recommend wearing waterproof clothing and protection while working outdoors, including gloves and long-sleeve shirts and pants.

While there is no evidence of spread to the larger community, according to the department, residents should wash hands frequently and work to control rodents around their property if possible.

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Pet owners can consult a veterinarian about leptospirosis vaccinations and should keep pets away from ponds, lakes and other natural bodies of water.

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Political stress: Can you stay engaged without sacrificing your mental health?

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Political stress: Can you stay engaged without sacrificing your mental health?

It’s been two weeks since Donald Trump won the presidential election, but Stacey Lamirand’s brain hasn’t stopped churning.

“I still think about the election all the time,” said the 60-year-old Bay Area resident, who wanted a Kamala Harris victory so badly that she flew to Pennsylvania and knocked on voters’ doors in the final days of the campaign. “I honestly don’t know what to do about that.”

Neither do the psychologists and political scientists who have been tracking the country’s slide toward toxic levels of partisanship.

Fully 69% of U.S. adults found the presidential election a significant source of stress in their lives, the American Psychological Assn. said in its latest Stress in America report.

The distress was present across the political spectrum, with 80% of Republicans, 79% of Democrats and 73% of independents surveyed saying they were stressed about the country’s future.

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That’s unhealthy for the body politic — and for voters themselves. Stress can cause muscle tension, headaches, sleep problems and loss of appetite. Chronic stress can inflict more serious damage to the immune system and make people more vulnerable to heart attacks, strokes, diabetes, infertility, clinical anxiety, depression and other ailments.

In most circumstances, the sound medical advice is to disengage from the source of stress, therapists said. But when stress is coming from politics, that prescription pits the health of the individual against the health of the nation.

“I’m worried about people totally withdrawing from politics because it’s unpleasant,” said Aaron Weinschenk, a political scientist at the University of Wisconsin–Green Bay who studies political behavior and elections. “We don’t want them to do that. But we also don’t want them to feel sick.”

Modern life is full of stressors of all kinds: paying bills, pleasing difficult bosses, getting along with frenemies, caring for children or aging parents (or both).

The stress that stems from politics isn’t fundamentally different from other kinds of stress. What’s unique about it is the way it encompasses and enhances other sources of stress, said Brett Ford, a social psychologist at the University of Toronto who studies the link between emotions and political engagement.

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For instance, she said, elections have the potential to make everyday stressors like money and health concerns more difficult to manage as candidates debate policies that could raise the price of gas or cut off access to certain kinds of medical care.

Layered on top of that is the fact that political disagreements have morphed into moral conflicts that are perceived as pitting good against evil.

“When someone comes into power who is not on the same page as you morally, that can hit very deeply,” Ford said.

Partisanship and polarization have raised the stakes as well. Voters who feel a strong connection to a political party become more invested in its success. That can make a loss at the ballot box feel like a personal defeat, she said.

There’s also the fact that we have limited control over the outcome of an election. A patient with heart disease can improve their prognosis by taking medicine, changing their diet, getting more exercise or quitting smoking. But a person with political stress is largely at the mercy of others.

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“Politics is many forms of stress all rolled into one,” Ford said.

Weinschenk observed this firsthand the day after the election.

“I could feel it when I went into my classroom,” said the professor, whose research has found that people with political anxiety aren’t necessarily anxious in general. “I have a student who’s transgender and a couple of students who are gay. Their emotional state was so closed down.”

That’s almost to be expected in a place like Wisconsin, whose swing-state status caused residents to be bombarded with political messages. The more campaign ads a person is exposed to, the greater the risk of being diagnosed with anxiety, depression or another psychological ailment, according to a 2022 study in the journal PLOS One.

Political messages seem designed to keep voters “emotionally on edge,” said Vaile Wright, a licensed psychologist in Villa Park, Ill., and a member of the APA’s Stress in America team.

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“It encourages emotion to drive our decision-making behavior, as opposed to logic,” Wright said. “When we’re really emotionally stimulated, it makes it so much more challenging to have civil conversation. For politicians, I think that’s powerful, because emotions can be very easily manipulated.”

Making voters feel anxious is a tried-and-true way to grab their attention, said Christopher Ojeda, a political scientist at UC Merced who studies mental health and politics.

“Feelings of anxiety can be mobilizing, definitely,” he said. “That’s why politicians make fear appeals — they want people to get engaged.”

On the other hand, “feelings of depression are demobilizing and take you out of the political system,” said Ojeda, author of “The Sad Citizen: How Politics is Depressing and Why it Matters.”

“What [these feelings] can tell you is, ‘Things aren’t going the way I want them to. Maybe I need to step back,’” he said.

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Genessa Krasnow has been seeing a lot of that since the election.

The Seattle entrepreneur, who also campaigned for Harris, said it grates on her to see people laughing in restaurants “as if nothing had happened.” At a recent book club meeting, her fellow group members were willing to let her vent about politics for five minutes, but they weren’t interested in discussing ways they could counteract the incoming president.

“They’re in a state of disengagement,” said Krasnow, who is 56. She, meanwhile, is looking for new ways to reach young voters.

“I am exhausted. I am so sad,” she said. “But I don’t believe that disengaging is the answer.”

That’s the fundamental trade-off, Ojeda said, and there’s no one-size-fits-all solution.

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“Everyone has to make a decision about how much engagement they can tolerate without undermining their psychological well-being,” he said.

Lamirand took steps to protect her mental health by cutting social media ties with people whose values aren’t aligned with hers. But she will remain politically active and expects to volunteer for phone-banking duty soon.

“Doing something is the only thing that allows me to feel better,” Lamirand said. “It allows me to feel some level of control.”

Ideally, Ford said, people would not have to choose between being politically active and preserving their mental health. She is investigating ways to help people feel hopeful, inspired and compassionate about political challenges, since these emotions can motivate action without triggering stress and anxiety.

“We want to counteract this pattern where the more involved you are, the worse you are,” Ford said.

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The benefits would be felt across the political spectrum. In the APA survey, similar shares of Democrats, Republicans and independents agreed with statements like, “It causes me stress that politicians aren’t talking about the things that are most important to me,” and, “The political climate has caused strain between my family members and me.”

“Both sides are very invested in this country, and that is a good thing,” Wright said. “Antipathy and hopelessness really doesn’t serve us in the long run.”

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Video: SpaceX Unable to Recover Booster Stage During Sixth Test Flight

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Video: SpaceX Unable to Recover Booster Stage During Sixth Test Flight

President-elect Donald Trump joined Elon Musk in Texas and watched the launch from a nearby location on Tuesday. While the Starship’s giant booster stage was unable to repeat a “chopsticks” landing, the vehicle’s upper stage successfully splashed down in the Indian Ocean.

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