The wave of tree deaths on Mammoth Mountain, which lies within one of the nation’s largest active volcanic systems, prompted scientists to start monitoring the volcano’s emissions more closely.

Now, researchers led by Stanford University geologist George Hilley have made a surprising discovery in the long-running record: The ebb and flow of carbon dioxide emissions from Mammoth Mountain are strongly linked to the weight of snow and ice atop the Sierra Nevada, and to the amount of water that percolates from ground level down into the volcano’s plumbing.

“This really shows how the solid Earth is coupled to climate and the things that go on at the surface,” said Hilley, professor of geological sciences in Stanford’s School of Earth, Energy & Environmental Sciences (Stanford Earth). “Droughts can change the way in which volcanoes breathe.”

The research, published March 9 in Geophysical Research Letters, comes amid a dry winter that has left California snowpack well below average for this time of year, with less than a week remaining in the state’s wet season and no major snowstorms in the forecast.

By the end of this century, state officials predict the Sierra Nevada snowpack will decline by 48 to 65 percent from the historical April 1 average. “Changes in Earth’s hydrology due to climate change could actually impact something like the tempo at which gases are emitted from volcanic systems,” Hilley said.

Horseshoe Lake

Hilley and coauthors analyzed measurements of carbon dioxide emissions taken every 30 minutes for six years from Horseshoe Lake, the best-studied tree kill area on Mammoth Mountain. The mountain rises along the southwest rim of Long Valley Caldera, a crater formed by a supervolcano eruption 760,000 years ago.

The results reveal a persistent 20 percent reduction in the amount of carbon dioxide seeping up from the ground during the spring of 2017. The downshift coincides with the region’s emergence from intense drought and the pileup of the biggest Sierra Nevada snowpack in decades.

The study builds upon research by USGS volcanologist Jennifer Lewicki showing that carbon dioxide emissions in the Horseshoe Lake tree-kill area changed seasonally and across multiple years for reasons unrelated to a brewing eruption.

Seeking an explanation for these variations, Lewicki and Hilley — with coauthor Curtis Baden of Stanford — developed mathematical models to test out plausible mechanisms. Snowmelt and rainfall can wash away carbon dioxide that might otherwise seep from the ground, for example. But their calculations show Mammoth Mountain receives far too little precipitation to account for the low springtime CO₂ levels observed in 2017.

The most likely explanation for the seasonal changes in Mammoth Mountain’s carbon dioxide emissions has to do with an underground crack, or fault, which to a trained eye is evident in the vegetation patterns and topography of the landscape. Changes in the distribution of stress across the whole mountain range seem to open and close the fault like a valve, or like the tiny gaps between old floorboards that flex under shifting weight.

Using GPS data and snow depth measurements, the authors found compressive force on the fault between 2014 and 2020 generally peaked in winter as snowpack accumulated across the Sierra Nevada and eased during snow-free summer months. Carbon dioxide emission levels dipped during periods when the weight of snow and water in the mountains flexed Earth’s crust, squeezing together the rocks on either side of the Mammoth Mountain fault.

One limitation of the study is that it does not provide a physics-based model of the fault’s movement and how gas flows through it. “We’re using stress changes as proxies for the opening and closing of a conduit,” Hilley said. “An interesting study would run a three-dimensional model of gas transport through a conduit that you could actually open and close, and then run that model many times to see if its predictions quantitatively match the carbon dioxide measurements we’re making.”

Predicting future eruptions

The ability to distinguish between CO₂ fluctuations driven by climate from those driven by an impending eruption will enable better hazard forecasts, which are based partly on signs that rising magma is triggering earthquakes, deforming the ground surface or ushering gases upward. “The alignment of all three of those is generally a clue that an eruption might be about to happen,” Hilley said.

For decades, ground deformation and seismicity around some of the United States’ active volcanoes have been monitored continuously using GPS and satellites, and scientists can view the data in close to real time. But they have a murkier view on volcanic gas. “In the past, at most volcanoes, scientists had to go into a volcanic area in advance of an eruption, or even between eruptions, and go collect this gas for later analysis. It’s real Indiana Jones-type stuff,” said Hilley.

The difficulty of collecting volcanic gases has resulted in limited records, sometimes with only a single snapshot of a volcano’s degassing in any given year, which makes it challenging to detect changes that may warn of an eruption — or to understand patterns linked to Earth’s climate system.

The new study offers a glimpse of insights to come as scientists gain access to more volcanic emission data, thanks in part to the development of less expensive and more durable instruments.

“The hope is, in the next couple years, we can have a record of what the gas is doing in near real time,” Hilley said. “When you look in detail, you can see there are seasonal fluctuations that probably have nothing to do with the actual volcanic state.”

So when researchers from the lab of University of Michigan aerosol scientist Kerri Pratt collected aerosols from the Arctic atmosphere during summer 2015, Rachel Kirpes, then a doctoral student, discovered a curious thing: Aerosolized ammonium sulfate particles didn’t look like typical liquid aerosols.

Working with fellow aerosol scientist Andrew Ault, Kirpes discovered that ammonium sulfate particles, which should have been liquid, were actually solid. The team’s results are published in the Proceedings of the National Academy of Sciences.

Solid aerosols can change how clouds form in the Arctic. And, as the Arctic loses ice, researchers expect to see more of these unique particles formed from oceanic emissions combined with ammonia from birds, which will impact cloud formation and climate. Additionally, understanding the characteristics of aerosols in the atmosphere is critical for improving the ability of climate models to predict current and future climate in the Arctic and beyond.

“The Arctic is warming faster than anywhere else in the world. As we have more emissions from open water in the atmosphere, these types of particles could become more important,” said Pratt, associate professor of chemistry, and earth and environmental sciences. “These types of observations are so critical because we have so few observations to even evaluate the accuracy of models of the Arctic atmosphere.

“With so few observations, sometimes you get surprises like this when you make measurements. These particles didn’t look like anything we had ever seen in the literature, in the Arctic, or anywhere else in the world.”

The aerosols observed in the study were up to 400 nanometers, or about 300 times smaller than the diameter of a human hair. Ault, associate professor of chemistry, says that aerosols in the Arctic are typically assumed to be liquid.

Once the relative humidity of the atmosphere reaches 80% — about the level of a humid day — the particle becomes liquid. When you dry the aerosol back out, it doesn’t turn into a solid until the relative humidity is about 35%-40%. Because the air over the Arctic Ocean — or any ocean — is humid, researchers expect to see liquid aerosols.

“But what we saw is a pretty new phenomenon where a small particle collides with our droplets when it’s below 80% humidity, but above 40% humidity. Essentially, this provides a surface for the aerosol to solidify and become a solid at a higher relative humidity than you would have expected,” Ault said.

“These particles were much more like a marble than a droplet. That’s really important, particularly in a region where there haven’t been a lot of measurements because those particles can eventually end up acting as the seeds of clouds or having reactions happen on them.”

Additionally, the researchers say, the size, composition and phase of atmospheric aerosols impact climate change through water uptake and cloud formation.

“It’s our job to keep helping modelers refine their models,” Ault said. “It’s not that the models are wrong, but they always need more new information as events on the ground change, and what we saw was something completely unexpected.”

Pratt’s team collected aerosols in August-September 2015 in Utqia?vik, the northernmost point of Alaska. To do this, they used what’s called a multistage impactor, a device that has several stages that collect particles according to their size. Kirpes later analyzed these particles in Ault’s lab using microscopy and spectroscopy techniques that can examine the composition and phase of particles less than 100 nanometers in size.

“If we were to go back several decades when there was ice near the shore, even in August and September, we would not be observing these particles. We’re observing the consequences of this climate already changing,” Pratt said. “We need to have the reality captured in models that simulate clouds and the atmosphere, which are critical for understanding the energy budget of the Arctic atmosphere, for this place that is changing faster than anywhere else.”

Findings from a randomized controlled crossover study led by Naima Covassin, Ph.D., a cardiovascular medicine researcher at Mayo Clinic, show that lack of sufficient sleep led to a 9% increase in total abdominal fat area and an 11% increase in abdominal visceral fat, compared to control sleep. Visceral fat is deposited deep inside the abdomen around internal organs and is strongly linked to cardiac and metabolic diseases.

The findings are published in the Journal of the American College of Cardiology, and the study was funded by the National Heart, Lung and Blood Institute.

Lack of sufficient sleep is often a behavior choice, and this choice has become increasingly pervasive. More than one-third of adults in the U.S. routinely do not get enough sleep, in part due to shift work, and smart devices and social networks being used during traditional sleep times. Also, people tend to eat more during longer waking hours without increasing physical activity.

“Our findings show that shortened sleep, even in young, healthy and relatively lean subjects, is associated with an increase in calorie intake, a very small increase in weight, and a significant increase in fat accumulation inside the belly,” says Virend Somers, M.D., Ph.D., the Alice Sheets Marriott Professor of Cardiovascular Medicine, and principal investigator of the study.

“Normally, fat is preferentially deposited subcutaneously or under the skin. However, the inadequate sleep appears to redirect fat to the more dangerous visceral compartment. Importantly, although during recovery sleep there was a decrease in calorie intake and weight, visceral fat continued to increase. This suggests that inadequate sleep is a previously unrecognized trigger for visceral fat deposition, and that catch-up sleep, at least in the short term, does not reverse the visceral fat accumulation. In the long term, these findings implicate inadequate sleep as a contributor to the epidemics of obesity, cardiovascular and metabolic diseases,” says Dr. Somers.

The study cohort consisted of 12 healthy people who were not obese, each spending two 21-day sessions in the inpatient setting. Participants were randomly assigned to the control (normal sleep) group or restricted sleep group during one session and the opposite during the next session, after a three-month washout period. Each group had access to free choice of food throughout the study. Researchers monitored and measured energy intake; energy expenditure; body weight; body composition; fat distribution, including visceral fat or fat inside the belly; and circulating appetite biomarkers.

The first four days were an acclimation period. During this time, all participants were allowed nine hours in bed to sleep. For the following two weeks, the restricted sleep group was allowed four hours of sleep and the control group maintained with nine hours. This was followed by three days and nights of recovery with nine hours in bed for both groups.

The participants consumed more than 300 extra calories per day during sleep restriction, eating approximately 13% more protein and 17% more fat, compared to the acclimation stage. That increase in consumption was highest in the early days of sleep deprivation and then tapered off to starting levels during the recovery period. Energy expenditure stayed mostly the same throughout.

“The visceral fat accumulation was only detected by CT scan and would otherwise have been missed, especially since the increase in weight was quite modest — only about a pound,” Dr. Covassin says. “Measures of weight alone would be falsely reassuring in terms of the health consequences of inadequate sleep. Also concerning are the potential effects of repeated periods of inadequate sleep in terms of progressive and cumulative increases in visceral fat over several years.”

Dr. Somers says behavioral interventions, such as increased exercise and healthy food choices, need to be considered for people who cannot easily avoid sleep disruption, such as shift workers. More study is needed to determine how these findings in healthy young people relate to people at higher risk, such as those who are already obese, or have metabolic syndrome or diabetes.

Story Source:

Materials provided by Mayo Clinic. Original written by Terri Malloy. Note: Content may be edited for style and length.

But as a new UBC Okanagan study finds, in central British Columbia there is one herd of mountain caribou, the Klinse-Za, whose numbers are going in the opposite direction — all thanks to a collaborative recovery effort led by West Moberly First Nations and Saulteau First Nations.

In partnership with many organizations and governments, the Indigenous-led conservation initiative paired short-term recovery actions such as predator reduction and caribou guardians at maternal pens, with ongoing work to secure landscape-level protection in an effort to create a self-sustaining caribou population.

Their efforts paid off.

Dr. Clayton Lamb, a Liber Ero Fellow, along with Carmen Richter, a biology master’s student, and Dr. Adam T. Ford, Canada Research Chair in Wildlife Restoration Ecology, conduct research in the Irving K. Barber Faculty of Science. Their latest study shows Klinse-Za caribou numbers have nearly tripled in under a decade.

“We have an Indigenous-led conservation effort to thank for averting the looming extinction of this herd,” says Dr. Lamb. “The population was declining rapidly — a West Moberly Elder once described the herd as a ‘sea of caribou,’ but by 2013 it had declined to only 38 animals.”

Today, the herd count is more than 110 and numbers continue to rise.

“This work provides an innovative, community-led, paradigm shift to conservation in Canada,” Dr. Lamb says. “While Indigenous Peoples have been actively stewarding landscapes for a long time, this approach is new in the level of collaboration among western scientists and Indigenous Peoples to create positive outcomes on the land and put an endangered species on the path to recovery.”

Richter, who is a Saulteau First Nations member, says Indigenous communities have really come together for the good of the caribou.

“We are working hard to recover these caribou. Each year, community members pick bags and bags of lichen to feed the mother caribou in the pen while other members live up at the top of the mountain with the animals. One day, we hope to return the herds to a sustainable size,” she says.

Though the partnership has yielded great success, Dr. Ford is the first to acknowledge that more time and effort will be needed to fully recover the Klinse-Za.

“This work is also an important part of decolonizing the mindset of conservation, which has historically worked to exclude the views of Indigenous Peoples,” he adds.

With caribou declines exceeding 40 per cent in recent decades across Canada, many populations have already been lost. But Dr. Ford insists there is a brighter path forward, and this study proves it.

“This is truly an unprecedented success and signals the critical role that Indigenous Peoples can play in conservation,” he says. “I hope this success opens doors to collaborative stewardship among other communities and agencies. We can accomplish so much more when working together.”

This study was co-produced by western scientists and members of West Moberly First Nations and Saulteau First Nations. The work was recently published in Ecological Applications and is supported by a companion manuscript in Ecological Applications exploring the expeditious population growth.