LA may be spared 'horrifying' fate of the 'Big One' from San Andreas, simulation suggests

By Stephanie Pappas

 

A new simulation of the shaking from a magnitude 7.8 south San Andreas earthquake suggests that Los Angeles might avoid a worst-case scenario.

A photo of downtown Los Angeles. (Image credit: Cavan Images / Toby Harriman via Getty Images)

Los Angeles is at risk of a major earthquake, but new research shows that the shaking from the "Big One" may not be as catastrophic as scientists initially feared. 

A new simulation of the shaking from a magnitude 7.8 earthquake on the south San Andreas fault suggests that LA may see 50% less ground motion than previously predicted. 

That could be good news for the City of Angels, but residents (and builders) shouldn't let their guard down, researchers say — there are still many questions about the damage a large quake could wreak in the region. 

"This is only one scenario," said study co-author Te-Yang Yeh, a postdoctoral researcher at San Diego State University. 

The study has not yet undergone peer review but appears on the preprint site ESS Open Archive. The study updates computer modeling first conducted during the 2008 Great Southern California ShakeOut, a project designed to quantify the consequences of a magnitude 7.8 quake on the southern San Andreas fault, which runs 30 miles (50 kilometers) east of downtown LA. 

According to the Statewide California Earthquake Center, such a worst-case quake is expected to cause 1,800 deaths, 50,000 injuries and $200 billion in damage. 

ShakeOut predicted surprisingly dramatic ground motion in downtown LA, said Thomas Heaton, a professor emeritus of geophysics and mechanical and civil engineering at Caltech, who was not involved in the new study. 

"That made quite a stir at the time, and then a number of us in the field were wondering whether or not the simulations were appropriate," Heaton told Live Science. In particular, the simulations suggested that the basins around the city – from the San Gabriel basin where Pasadena sits to the Los Angeles basin that holds its eponymous city — would act as what's called a "waveguide," funneling earthquake waves right toward the city. But basins are structurally complicated, Heaton said, so it's not clear whether they'd be such perfect channels. 

The quake simulations used in the ShakeOut project were not as detailed as today's technology allows, Yeh told Live Science. For example, the models represented the surface between the fault and LA as smooth. Yeh and Kim Olsen, a seismologist at San Diego State who co-authored the study, used a new simulation that included actual topography as well as detailed information about the geometry of the fault and the way waves travel through the subsurface. 

The Carrizo Plains provides good visibility of the San Andreas Fault in southern California. (Image credit: Kevin Schafer via Getty Images)

Their results showed a better outlook for LA. "The ground motions are still profound," Yeh said, "but it's not as horrifying as what was previously predicted."

While the basins around LA do channel earthquake waves to some extent, the researchers found, the mountainous topography around the fault also has a scattering effect. Thus, the waves going into the basins aren't as strong as previously expected, so neither are the waves coming out. 

Still, that doesn't mean Southern Californians can rest easy. 

"It's important that they actually redid this calculation, and I applaud them for that," Heaton said. "That's how good science progresses. But what is still missing in the entire analysis is real data from earthquakes." 

The area is now well-observed by a network of seismic monitors, Heaton said, but more quakes will have to occur to get those data points. 

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Another consideration is that ground motion could vary a lot even within the Los Angeles area, regardless of what the whole city's average shaking looks like, said Zachary Ross, a geophysicist at Caltech who was not involved in the new research. 

The middle of the Los Angeles basin sits on sediments, Ross said, which are relatively loose and can move easily in a quake, whereas the areas closer to the mountains may have more rigid, resistant rock. There are also multiple other fault networks beside the San Andreas near Los Angeles, and they create their own hazards. 

"That's part of what makes this whole problem just so challenging," Ross told Live Science. "At the end of the day, even if you could get this one simulation fairly reasonable, it's just one of them." 

You need *this* kind of sleep at the weekend to reduce working-week exhaustion, study shows

Employees were better able to focus on Monday

DALY AND NEWTON//GETTY IMAGE

It's nothing new, but we'll say it again: sleeping well will make you feel less tired. Specifically, a new study published in the Journal of Organisational Behaviour has shown that higher sleep quality during weekends is associated with slightly lower levels of exhaustion during the work week.

Researchers at the University of Mannheim, Germany, hypothesised that employees would report better psychological 'reattachment' to work after experiencing higher quality sleep on Saturdays and Sundays, as they would be more easily able to employ energetic and cognitive resources.

Conversely, they predicted that weekends with 'catch-up' sleep (inconsistent sleep that was making up for a sleep debt), or where sleep was disrupted or irregular due to leisure activities ('social sleep'), would be followed by lower levels of reattachment to work on Monday.

They also thought that employees who 'reattached' better on Monday would subsequently experience reduced exhaustion and higher task performance during the work week.

How was the study conducted?

310 employed individuals from Germany were asked to complete a weekly diary study, answering surveys on Mondays and Fridays. On Mondays, they self-reported their sleep during the weekend and how reattached they were to work; on Fridays, they assessed their work-week fatigue and task performance. Self-reporting and requiring participants to remember how they slept creates some limitations, however, in contrast to results produced by less subjective measures.

Participants were predominantly female (81%) and 41 years old on average. 55% had university degrees.

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What were the results?

Results showed that participants experienced better reattachment to work on Monday when they'd slept better over the weekend. In contrast, catch-up sleep was usually followed by lower reattachment on Monday, though the same could not be said for social sleep lag.

Lower reattachment on Monday was indeed linked to increased exhaustion for the rest of the work week, but that did not apply to task performance.

'Our findings suggest that high-quality sleep during the weekend can be beneficial, but catching up on sleep during the weekend can be detrimental to Monday reattachment and, in turn, indirectly to work-week exhaustion. Accordingly, we demonstrate that Monday reattachment can set the tone for the entire work week, but the capability to reattach depends on weekend sleep as a core recovery process,' the study authors said.

So while a great weekend can pep you up for the week ahead, it might also be advisable to use sleep over the weekend to rest and recover fully... but you knew that already, didn't you?

 

Scientists find new way global air churn makes particles

by Leah Shaffer, Washington University in St. Louis

Credit: Unsplash/CC0 Public Domain

You can think of our atmosphere as a big chemistry set, a global churn of gaseous molecules and particles that constantly bounce off and change each other in complicated ways. While the particles are very small, often less than 1% of the thickness of human hair, they have outsized impacts. For example, particles are the seeds of cloud droplets, and the abundance of the particles changes the reflectivity and the amount of clouds, rainfall and climate.

Now, researchers at Washington University in St. Louis have discovered something new in the sky, a mechanism that produces a large portion of particles in Earth's atmosphere.

The research, published in Science this month, was led by Jian Wang, professor and director of the Center for Aerosol Science and Engineering at WashU. The research team includes Lu Xu, assistant professor in WashU's Department of Energy, Environmental and Chemical Engineering at the McKelvey School of Engineering and scientists from NASA, NOAA, NCA, and European universities.

The conventional thinking was that most particle formation occurs in cloud outflow regions, where clouds float into the upper troposphere and eventually evaporate. In that process, clouds are getting wrung out and most particles are removed by rain. As a result, the air in the outflow regions is clear and clean, leaving some gaseous molecules with nowhere to go but form new particles.

"However, using the data collected from NASA's global-scale aircraft measurements, we found that most of the new particles are not formed in the outflow regions as previously thought," Wang said.

While puzzling over this surprising observation, Wang and colleagues ended up discovering a whole different mechanism taking place when the mixing of stratospheric and tropospheric air results in conditions that are ripe for particle formation.

"Stratosphere air often dips in troposphere due to meandering jet stream. As the ozone-rich stratospheric air and more moist tropospheric air mix, it leads to a high concentration of hydroxyl radical (OH), an important oxidant that helps produce the type of molecules that nucleate and form new particles," said Jiaoshi Zhang, first author on the study and a research scientist in Wang's lab.

"We found this phenomenon is widespread around the globe and likely occurs more frequently than the particle formation in the cloud outflows," he added.

Future field observations and modeling studies will be needed to confirm and further quantify the importance of this newly discovered mechanism of particle formation. Obviously, humans contribute their own particles in the form of air pollution, but Wang said what was discovered in this research is a natural process that occurs around the globe, even in remote and pristine regions.

There is also some evidence the stratospheric air will dip into troposphere more frequently in future climate, so this mechanism may become even more important, Wang said. Including this previously unknown process can improve climate models and may help better simulate climate change and predict future climate.

"While we are puzzled by the observation initially, once we put everything together, afterwards it was not so surprising," Wang said.

"It is well known that molecules forming new particles are generated through oxidation in the atmosphere. When the stratosphere and troposphere air mix, the OH concentration is very high, and it's primed for particle formation."

More information: Jiaoshi Zhang et al, Stratospheric air intrusions promote global-scale new particle formation, Science (2024). DOI: 10.1126/science.adn2961

Journal information: Science 

Provided by Washington University in St. Louis Discovering a new way by which aerosols rapidly form and grow at high altitude

Archaeologists Unearth 4,000-Year-Old Ceremonial Temple in Peru

The structure appears to predate Machu Picchu, the country’s best-known archaeological site, by 3,500 years



Ella Feldman
Daily Correspondent

SMITHSONIAN

July 12, 2024 

Luis Muro Ynoñán poses with a carving of a mythological bird-like creature

. Ucupe Cultural Landscape Archaeological Project

Researchers in Peru say they have found the remains of a 4,000-year-old temple and theater, a discovery that could enrich historians’ understanding of ancient religious practices in the region.

“We still know very little about how and under which circumstances complex belief systems emerged in the Andes,” says Luis Muro Ynoñán, an archaeologist from Peru’s Pontifical Catholic University who led the team, in a statement. “Now we have evidence about some of the earliest religious spaces that people were creating in this part of the world.”

The ruins appear to predate Machu Picchu, the Inca settlement that is now Peru’s best-known archaeological site, by roughly 3,500 years. The researchers say they also predate pre-Inca cultures such as the Moche and Nazca.

“We don’t know what these people called themselves, or how other people referred to them,” Muro Ynoñan adds. “All we know about them comes from what they created: their houses, temples and funerary goods.”

Last month, researchers began excavating a 33- by 33-foot plot of land located near Zaña, a town in coastal Peru. Just six feet below the surface, they found evidence of ancient walls made of mud and clay.

The structure appears to have been a section of a larger temple, which may have been built into the mountainside. The team also found the remains of a small theater, which “could have been used to perform ritual performances in front of a selected audience,” per Muro Ynoñan.

The archaeologist tells Reuters’ Marco Aquino that he is still waiting for the results of radiocarbon testing, which will confirm the site’s age. In the meantime, he is estimating the date based in part on an elaborately carved image found along one of the theater’s staircases. The carving, which depicts a mythological bird-like creature, resembles other artworks from the Initial Period (around 2000 to 900 B.C.E.)—or about 4,000 years ago.

“The Initial Period is important because it’s when we first start to see evidence of an institutionalized religion in Peru,” says Muro Ynoñan in the statement. “The bird creature at this temple resembles a figure known from the Chavín region, nearly 500 years later. This new site could help reveal the origins of this religion.”

The team also unearthed large murals painted on the walls. Muro Ynoñán collected pigment samples, which he plans to analyze back in the lab. He hopes to determine where the paints came from, which would shed light on which groups the ancient site’s builders were trading with.

Additionally, the researchers found the skeletal human remains of three adults inside the temple, per Reuters. One was buried alongside offerings and appears to have been wrapped in some kind of cloth.

According to a statement from the Peruvian Ministry of Culture, archaeologists also discovered a second ceremonial temple nearby. This site is considerably older, dating to between 600 and 700 C.E., and is likely connected to the Moche culture.

The Ocean Is Getting Sicker

Pathogens are surging and new diseases are emerging.

BY MARYN MCKENNA
July 12, 2024
 

At the end of January, Christina Pettan-Brewer’s WhatsApp chats started blowing up. Pettan-Brewer, a wildlife veterinarian at the University of Washington School of Medicine, was born—and earned her first degree—in Brazil, and the messages from scientist acquaintances were all about the Brazilian coast. A “red tide” was underway. The temperature-driven bloom of phytoplankton was staining the beaches of Pernambuco and Alagoas states.

Red tides, which are caused by harmful blooms of algae, are not unknown on the coast of Brazil. In 2022, one stretched for more than 120 miles near Rio de Janeiro and lasted for eight weeks. But the bloom this year was unusually intense: More than 500 people sought medical care for symptoms, including vomiting and skin irritation, caused by the algae’s toxins.

Are there truly more marine diseases now than in the past?

To Pettan-Brewer and her professional circle, the episode was the latest evidence of a trend they have worried about for years. The health of the ocean, they say, is failing. As human activities—including climate change—stress marine ecosystems, pathogens are surging out of balance and new diseases are emerging. And though researchers have become accustomed to viewing terrestrial disease emergence through a “One Health” lens, treating the environment, other animals, and humans as one interconnected system, they have only recently started to look at the ocean this way.

“The world is not thinking about the ocean,” Pettan-Brewer says. “Except for people who live on the coasts or work there, the ocean is largely out of view.”

That is changing. In 2022, Pettan-Brewer and other scientists gathered at Kiel University in Germany for the second International Ocean Health Symposium. (The first such conference, held in December 2020 in Monaco, was undercut by the COVID-19 pandemic.) Out of that meeting emerged an international project, Beyond One Ocean Health, based at Kiel University and supported by the United Nations Ocean Decade initiative, that is studying whether marine diseases are increasing in frequency and severity.

The collaborators in this new research suspect that the ocean is becoming not just unusually stressed—witness the hot-tub temperatures recorded in Florida coastal waters last year—but also newly vulnerable to disease, as demonstrated in outbreaks that affect species from mammals to shellfish to corals; in mass die-offs and species disappearances; and in population explosions such as that red tide bloom.

But that proposition remains to be empirically demonstrated. Are there truly more marine diseases now than in the past? Or might people in an increasingly crowded, connected world simply be more aware of them?

The health of the ocean, they say, is failing.

A challenge for the researchers is determining when disease outbreaks are doing the predictable work of promoting ecosystem resilience and function. Trematode parasites, for instance, help regulate populations of fish and shellfish, helping prevent any one species from overproliferating and destabilizing their community. “A healthy ecosystem may need disease as a control mechanism,” says Marie-Catherine Riekhof, an economist and director of Kiel’s Center for Ocean and Society.

Still, the number and variety of disease events recorded in recent decades suggest that more than predictable self-regulation is going on. Twenty years ago, researchers at Cornell University and the University of California, Santa Barbara surveyed the scientific literature for reports of disease outbreaks in marine plants and animals; after adjusting for more studies being published than in the past, they concluded that diseases had increased in turtles, corals, mammals, urchins, and molluscs since 1970. (They also found that diseases had decreased in fishes—but speculated that might be because, thanks to overfishing, there were simply fewer of them.)

Since that time, extensive disease outbreaks have been recorded in marine mammals, including Toxoplasma gondii (an organism carried by domestic cats) in whales and avian influenza killing sea lions. At least 67 bacterial diseases have been blamed for reducing harvests of wild and cultivated salmon and other farmed seafoods. Multiple diseases of corals, including those that led to severe bleaching, have been recorded in warming waters. Even infections in marine plants are reshaping ecosystems, such as an epidemic that halved local populations of eelgrass in waters off the Pacific Northwest coast.

Those outbreaks mirror the rise of infectious diseases on land over the same time period, arising as people encroach on wild places, degrade habitats, and keep domesticated animals close to wildlife. Marine events are similarly fueled by human activities.

Fertilizers, pesticides, sewage, pharmaceuticals, industrial waste, and microplastics all end up in the ocean, creating conditions favorable to the spread of disease. Ships release ballast water—and the organisms in it—into ecosystems far from the ships’ origins. The rise of aquaculture, which frequently involves the long-distance transport of finfish and shellfish, destabilizes ecosystems by also transporting those species’ parasites to new ranges. At-sea aquaculture pens, overcrowded with highly stressed fish, are incubators for pathogens, and the antibiotics fed to farmed fish to control diseases may disrupt local bacterial populations as well as increasing antibiotic-resistant infections in predators such as seabirds. And some work has shown that, as populations are overfished, parasite populations also shift, becoming predominated by opportunistic generalists capable of attacking many species.

What worries scientists even more is what they cannot observe.

These impacts are amplified by the effects of a changing climate, from rising water temperatures, to increases in acidity and changes in ocean salinity, to the physical effects of storms and cyclones reshaping near-shore and underwater geography. Warming waters create new disease threats for humans too, as when three people died in New York and Connecticut last year from infections with Vibrio vulnificus, an ocean pathogen that previously had not circulated that far north.

Such outbreaks, deaths, and ecosystem changes are known because they were detected. What worries scientists even more is what they cannot observe.

Identifying the movement of pathogens in the open ocean and measuring their impact on free-living organisms is extraordinarily difficult. Reliably detecting them would require creating new forecasting models and surveillance systems to predict their movement, as well as diagnostic tools that could be deployed when disease emergence is suspected. Those would be expensive to develop and use—but unless societies address their multiple disease-promoting effects on the ocean, they may be the most expedient response to the spread of disease.

“The ocean has been so poorly observed,” says Anya Waite, a biological oceanographer who heads the Ocean Frontier Institute at Dalhousie University in Nova Scotia. The decades during which the One Health model excluded the ocean, though it covers most of Earth’s surface and contains the majority of its phyla, have left ocean science behind—not just in perceiving how human activities affect marine life, but also in how those impacts are changing over time. What would seem to be basic concepts—what pathogens are present, how they move through the ocean, whether specific hot spots for infection exist or are shifting—remain to be explored.

Reframing the One Health concept to include the ocean could change that. “Diseases are part of many other types of impacts to the environment,” says Kevin Lafferty, a marine ecologist with the United States Geological Survey and University of California, Santa Barbara. “We need to study them on equal footing with things like overfishing and pollution.”

Lead photo: Alfred Rowan / Shutterstock

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Maryn McKenna
Posted on July 12, 2024
Maryn McKenna (Threads / X / Instagram) is a journalist specializing in public health and global health, based in Atlanta. She is the author of Big Chicken, Superbug, and Beating Back the Devil, and a senior fellow at the Center for the Study of Human Health at Emory University.

Cambodia clamps down on environmental activists

Observers see the threat to Cambodia's rule of law and civil society growing after members of an award-winning environmental group were convicted of conspiring against the state.


Tommy Walker

DW

JULY 12,2024

Civil society monitoring groups say Cambodia's civic space is 'repressed'

Heng Sinith/AP Photo/picture alliance

Ten members of the Cambodian environmental activist group Mother Nature were sentenced to six to eight years in prison in July for conspiring against the state.

Three of the members of the group were also convicted of insulting Cambodia's king, Norodom Sihamoni.

The young activists had long campaigned against the destruction of natural resources across the Southeast Asian country and had openly suggested links to corruption.

The group was charged with "plotting" against the state after investigating waste pollution in Phnom Penh's Tone Sap River in 2021. In addition, a group statement from an online meeting was found to be insulting to the king which led to the charges against three members.

Only five of the activists attended the trial. Four of them attended the sentencing and were swiftly arrested by authorities. One was not present for the sentencing and five other activists, including Spanish national Alejandro Gonzalez-Davison, the co-founder of Mother Nature, were convicted in absentia.

Despite the threat of arrest, activists openly displayed support for their jailed colleagues

 Heng Sinith/AP Photo/picture alliance

Jacob Sims, a Southeast Asia regional expert on transnational crime and rights issues, told DW that activists could face a harsh clampdown if they were seen as posing a threat to the interests of Cambodia's elites.

"The real power in Cambodia lies not in its formal institutions, but in its complex and shadowy web of oligarchs with close ties to the prime minister's family," Sims said. "Wherever activists — across any sector — jeopardize the economic interests of this ruling elite, they risk the wrath of the formal Cambodian state apparatus."

"That is what happened in the recent case of overt court weaponization against the Mother Nature activists," Sims said.
A threat to civil society

Mother Nature Cambodia was founded in 2012 with the aim of protecting Cambodia's natural environment and human rights. For years, members of the group faced intimidation and threats and in 2017 it was deregistered as a nongovernment organization.

The group continued to advocate and in 2023 won a prestigious Right Livelihood award for its work.

Cambodia evicts Angkor Wat locals 06:09

Sims said the clampdown on the group showed that civil society in Cambodia is under threat.

"If concerned governments, multilaterals, international NGOs and global brands do not find it within themselves to stand with these courageous local activists and rapidly inject some accountability into this situation, it may be too late," said Sims. "We are witnessing the systematic evisceration of Cambodian civil society in real-time."

Civil society monitoring groups say Cambodia's civic space is "repressed." Union leaders and land rights activists have been jailed in recent years while humanitarian organizations and other NGOs have been threatened with dissolution.
A powerful ruling ‘dynasty'

The ruling Cambodian People's Party has faced little political threat to its power, and, leading up to the 2023 elections, Cambodia's electoral commission had already disqualified the country's main opposition, Cambodia's Candlelight Party.

Critics call Cambodia's leaders the "Hun Dynasty." Former Prime Minister Hun Sen ruled the country for nearly four decades and was one of the longest-serving leaders in the world before power was handed over to his son Hun Manet in 2023.

Mekong River threatened by dams, climate change  03:18

Vanna Hay, leader of the Cambodia National Rescue Movement, now in exile in Japan, said trials like that of Mother Nature Cambodia showed that government corruption is severely threatening Cambodia's rule of law.

"Because the current government is totally corrupted, so-called systematic corruption, they protect those destroying the environment for their benefit," he said.

Edited by: Ole Tangen Jr

 

Investigating variation in the permafrost active layer over the Tibetan Plateau from 1980 to 2020

by Chinese Academy of Sciences

Glaciers and permafrost over the Tibetan Plateau. Credit: Weichen Tao

The Tibetan Plateau hosts the world's largest permafrost region in the middle and low latitudes. Compared to the high-latitude Arctic permafrost, the permafrost here is thinner, warmer, and more sensitive to global warming. The active layer is a crucial zone for energy exchange between permafrost and the atmosphere, effectively reflecting the impact of climate change on permafrost.

Studying changes in the active layer thickness (ALT) helps towards a better understanding of the hydrological environment in permafrost regions. However, due to the complex and variable environment of the Tibetan Plateau, the simulation of ALT remains a subject of debate.

Recently, Jinglong Huang, from Hohai University, and Prof. Chaofan Li, from the Institute of Atmospheric Physics, Chinese Academy of Sciences, utilized the China Meteorological Forcing Dataset to drive the Community Land Model, version 5.0, for simulating and studying changes in ALT from 1980 to 2020 on the Tibetan Plateau. Their findings have recently been published in Atmospheric and Oceanic Science Letters.

The results show significant interdecadal changes in ALT on the Tibetan Plateau after the year 2000. The overall ALT of the plateau decreased from 2.54 m during 1980–1999 to 2.28 m during 2000–2020. This change took place mainly in the western permafrost region, displaying a sharp regional inconsistency with the eastern region where a persistent increasing trend was found, rather than an interdecadal change.

Additionally, the active layer area also displays an interdecadal change around the year 2000, characterized by a continuous decline before that year and almost no change thereafter. The study further found that the changes and regional differences in the active layer of the permafrost on the Tibetan Plateau are significantly influenced by environmental factors such as temperature and precipitation, reflecting the complex response to climate change under global warming.

"The terrain of the Tibetan Plateau is highly complex, and the calculation bias for permafrost in some areas is often large. Thus, we hope to simulate the ALT of the Tibetan Plateau using a high-performing land surface model combined with high-resolution meteorological forcing data to better approximate the actual situation," explains Dr. Li, the corresponding author of the study.

This result contributes to a better understanding of the transformation characteristics of the meteorological and hydrological environment in the permafrost regions of the Tibetan Plateau against the background of global warming, and to grasping the impact of climate change on the Tibetan Plateau's exchanges of water and heat.

More information: Jinglong Huang et al, Variation in the permafrost active layer over the Tibetan Plateau during 1980–2020, Atmospheric and Oceanic Science Letters (2024). DOI: 10.1016/j.aosl.2024.100536

Provided by Chinese Academy of Sciences Transformation and mechanisms of climate wet/dry change on the northern Tibetan Plateau under global warming