Faculty

Climate change fueling more severe wildfires in California

November 18, 2024

A new Environmental Research Letters study reveals that the severity of the state’s wildfires has rapidly increased over the last several decades, contributing to greater forest loss than would have been expected from past increases in burned areas.

“Fire severity increased by 30% between the 1980s and 2010s,” said Jon Wang, an assistant professor at the University of Utah School of Biological Sciences and former postdoctoral researcher at the University of California Irvine Department of Earth System Science. This means that for every acre of forest scorched by fire, the damages to mature trees are considerably higher than what occurred in the average fire several decades ago.

Jon Wang conducting field research in Norway. Photo credit: Acacia England, U.S. Forest Service

“When fire moves through an area on the forest floor, often mature trees survive and, in some situations, they may thrive from fire effects on nutrient cycling,” said study co-author James Randerson, professor in the UC Irvine Department of Earth System Science. “The new research suggests more fire is jumping into the tree crowns, causing more damage and tree mortality.”

Randerson added that wildfires also have moved into new areas with denser and more vulnerable forests. Those areas include northern mountain and coastal regions that may have been protected in the past by cooler summers and higher levels of surface moisture.

“Forest exposure has increased 41% over the past four decades, suggesting denser forests are now more vulnerable to wildfire,” said Wang, who joined the U last year and is the principal investigator for the Dynamic Carbon and Ecosystems lab.

The question Wang and his team wanted to answer was how much-rising tree cover loss in California is due to increases in total area burned, how much of the loss is due to increasing wildfire severity, and how much is due to fire moving into new areas with denser forests.

“There’s a pretty shocking map of just how much these fires have expanded into northern California forests,” Wang said. “There’s just a lot more fire in these northern forests than there used to be. Climate change allows severe fires to affect forests that once tolerated milder fires.”

Exploring the Cosmic Unknown

November 12, 2024

A dino-mite addition to SLC International Airport

October 28, 2024

On Tuesday, Oct. 22, the Salt Lake City International Airport and the Natural History Museum of Utah unveiled the airport’s first-ever dinosaur—Ally, a 30-foot-long, 15-foot-tall skeleton of Allosaurus fragilis.

“I’m absolutely thrilled to be here today to reveal a project that’s been 150 million years in the making,” Jason Cryan, executive director of NHMU, said to the crowd gathered to celebrate the completed Concourse B. “Turn around as we unveil Utah’s state fossil as it’s never been seen before!”

The Jurassic Park theme boomed from the speakers, and the airport assembly spun around and gasped as the curtain fell to reveal Ally in all her glory.

From the Late Jurassic to Concourse B

The museum has wanted a dinosaur at the airport for decades. The recent expansion and a gift from Kirk Ririe, Bob and Cyndi Douglass, and the Lawrence T. & Janet T. Dee Foundation made it happen.

“I’m originally from the Chicago area, and the O’Hare International Airport has an iconic Brachiosaurus skeleton that gets people excited. I’ve always wanted that for Salt Lake City’s airport,” said Randy Irmis, curator of paleontology at NHMU and professor of geology at the University of Utah. “Utah is known for its dinosaurs. We hope this inspires visitors and locals to explore the really cool dinosaur heritage of our state.”

Bringing together minds and resources for a greener tomorrow

October 11, 2024

With an ever-growing population in city, suburban, and rural areas, the Beehive State and region’s economic potential is growing.

But the climate challenges Utah and neighboring states face pose dire consequences for the environment and the region’s residents and businesses. The exposed lakebed of the Great Salt Lake; droughts causing water shortages and shrinking lakes; and vast air pollution from wildfire smoke are just some of the challenges being seen.

The climate challenges Utah and the region face are a threat, but these challenges can also drive innovation and create a robust workforce.

Recently, the University of Utah hosted the Southwest Sustainability Innovation Engine (SWSIE) Site Visit highlighting the achievements of the first year of this project. SWSIE is a new National Science Foundation (NSF)-funded program which includes academic, community, nonprofit and industry partners across Arizona, Nevada and Utah to establish the region as a leader in water security, renewable energy, and carbon management, and develop a workforce to support those high-wage industries.

The multi-day site visit showcased Utah’s efforts to make the state and the region a hub of green innovation. Some of the highlights of the event included field trips that spanned the watershed, examples of regional collaboration, partner engagement, building an ecosystem throughout the region, and workforce development, among other topics.

A key component of the NSF Engines program is to leverage existing partnerships and coordinate efforts among researchers, industry, and government to accelerate the pace of sustainability innovation and prepare a regional workforce.

“With SWSIE, we are able to accelerate the speed that things are happening,” said Dr. Brenda Bowen, Co-PI on the SWSIE project and serves as the University of Utah lead. “Even though we are acting so fast, it needs to be faster. There’s this urgency to it, and that so aligns with the urgency of the issues that we’re facing around climate. That’s an exciting thing that SWSIE can bring, that additional incentive to really accelerate things.”

Utah’s Natural Wonders: 3 New Geoheritage Sites

October 10, 2024

New models shed light on sea ice dynamics

October 2, 2024

It is far from a homogenous layer of frozen water on the ocean’s surface, but rather a dynamic mix of water and ice, as well as minute pockets of air and brine encased in the ice.

New research led by University of Utah mathematicians and climate scientists is generating fresh models for understanding two critical processes in the sea ice system that have profound influences on global climate: the flux of heat through sea ice, thermally linking the ocean and atmosphere, and the dynamics of the marginal ice zone, or MIZ, a serpentine region of the Arctic sea ice cover that separates dense pack ice from open ocean.

In the last four decades since satellite imagery became widely available, the width of the MIZ has grown by 40% and its northern edge has migrated 1,600 kilometers northward, according to Court Strong, a professor of atmospheric sciences.

A tale of two studies, one north and one south

Ice covering both polar regions has sharply receded in recent decades thanks to human-driven global warming. Its disappearance is also driving a feed-back loop where more of the sun energy’s is absorbed by the open ocean, rather than getting reflected back to space by ice cover.

Utah mathematics professors Elena Cherkaev and Ken Golden, a leading sea ice researcher, are authors on both studies. The Arctic study led by Strong examines the macrostructures of sea ice, while the Antarctic study, led by former Utah postdoctoral researcher Noa Kraitzman, gets into its micro-scale aspects.

How special is the Milky Way Galaxy?

September 25, 2024

Is our home galaxy, the Milky Way Galaxy, a special place? A team of scientists started a journey to answer this question more than a decade ago. Commenced in 2013, the Satellites Around Galactic Analogs (SAGA) Survey studies galaxy systems like the Milky Way. Now, the SAGA Survey just published three new research articles that provide us with new insights into the uniqueness of our own Milky Way Galaxy after completing the census of 101 satellite systems similar to the Milky Way’s.

These “satellites” are smaller galaxies in both mass and size which orbit a larger galaxy, usually called the host galaxy. Just as with smaller satellites that orbit the Earth, these satellite galaxies are captured by the gravitational pull of the massive host galaxy and its surrounding dark matter. The Milky Way Galaxy is the host galaxy of several satellite galaxies, of which the two largest are the Large and Small Magellanic Clouds (LMC and SMC). While LMC and SMC are visible to the naked eye from the Southern Hemisphere, there are many other fainter satellite galaxies orbiting around the Milky Way Galaxy that can only be observed with a large telescope.

The goal of the SAGA Survey is to characterize satellite systems around other host galaxies that have similar stellar masses as the Milky Way Galaxy. Yao-Yuan Mao, a University of Utah faculty member in the Department of Physics and Astronomy, is co-leading the SAGA Survey with Marla Geha at Yale University and Risa Wechsler at Stanford University. Mao is the lead author of the first article in the series of three that have all been accepted by the Astrophysical Journal. This series of articles reports on the SAGA Survey’s latest findings and makes the survey data available to other researchers worldwide.

An outlier galaxy?

An image of a Milky Way-like galaxy and its system of satellite galaxies. The SAGA survey identified six small satellite galaxies in orbit around this Milky Way analog. Credit: Yasmeen Asali (Yale), with images from the DESI Legacy Surveys Sky Viewer https://www.legacysurvey.org/acknowledgment/

In the first study led by Mao, the researchers highlighted 378 satellite galaxies identified across 101 Milky Way-mass systems. The number of confirmed satellites per system ranged from zero to 13 — compared to four satellites for the Milky Way. While the number of satellite galaxies in the Milky Way system is on par with the other Milky Way-mass systems, “the Milky Way appears to host fewer satellites if you consider the existence of the LMC,” Mao said. The SAGA Survey has found that systems with a massive satellite like the LMC tend to have a higher total number of satellites, and our Milky Way seems to be an outlier in this regard.

An explanation for this apparent difference between the Milky Way and the SAGA systems is the fact that the Milky Way has only acquired the LMC and SMC quite recently, compared with the age of the universe). The SAGA article explains that if the Milky Way Galaxy is an older, slightly less massive host with the recently added LMC and SMC, one would then expect a lower number of satellites in the Milky Way system not counting other smaller satellites that LMC/SMC might have brought in.

This result demonstrates the importance of understanding the interaction between the host galaxy and the satellite galaxies, especially when interpreting what we learn from observing the Milky Way. Ekta Patel, a NASA Hubble Postdoctoral Fellow at the U but not part of the SAGA team, studies the orbital histories of Milky Way satellites. After learning about the SAGA results, Patel said, “Though we cannot yet study the orbital histories of satellites around SAGA hosts, the latest SAGA data release includes a factor of ten more Milky Way-like systems that host an LMC-like companion than previously known. This huge advancement provides more than 30 galaxy ecosystems to compare with our own, and will be especially useful in understanding the impact of a massive satellite analogous to the LMC on the systems they reside in.”

Why do galaxies stop forming stars?

The second SAGA study of the series is led by Geha, and it explores whether these satellite galaxies are still forming stars. Understanding the mechanisms that would stop the star formation in these small galaxies is an important question in the field

Yao-Yuan Mao

of galaxy evolution. The researchers found, for example, that satellite galaxies located closer to their host galaxy were more likely to have their star formation “quenched,” or suppressed. This suggests that environmental factors help shape the life cycle of small satellite galaxies.

The third new study is led by Yunchong (Richie) Wang, who obtained his PhD with Wechsler. This study uses the SAGA Survey results to improve existing theoretical models of galaxy formation. Based on the number of quenched satellites in these Milky Way-mass systems, this model predicts quenched galaxies should also exist in more isolated environments — a prediction that should be possible to test in the coming years with other astronomical surveys such as the Dark Energy Spectroscopic Instrument Survey.

Gift to the astronomy community

In addition to these exciting results that will enhance our understanding of galaxy evolution, the SAGA Survey team also brings a gift to the astronomy community. As part of this series of studies, the SAGA Survey team published new distance measurements, or redshifts, for about 46,000 galaxies. “Finding these satellite galaxies is like finding needles in a haystack. We had to measure the redshifts for hundreds of galaxies to just identify one satellite galaxy,” Mao said. “These new galaxy redshifts will enable the astronomy community to study a wide range of topics beyond the satellite galaxies.”

The SAGA Survey was supported in part by the National Science Foundation and the Heising-Simons Foundation. Other authors of these three SAGA studies include Yasmeen Asali, Erin Kado-Fong, Nitya Kallivayalil, Ethan Nadler, Erik Tollerud, Benjamin Weiner, Mia de los Reyes, John F. Wu, Tom Abel, and Peter Behroozi.

U Scientists Nominate Iconic Utah Sites as Global Geoheritage Locations

September 24, 2024

He observed a “great depth of uplifted and arching strata”, which form domes of sedimentary rock over chambers of hardened “molten rock,” or what came to be called laccoliths.

G.K. Gilbert’s scientific exploration of the Henry Mountains led to the development of a mechanical model for mountain building that has remained valid for 150 years. In recognition of the its role in the history of geoscience, the southern Utah range has been selected as a world geoheritage site by the International Union of Geological Sciences (IUGS), along with two other features in Utah: the Great Salt Lake and Coyote Buttes, the sandstone landscape on the Arizona state line that includes The Wave.

Nominated by University of Utah geoscientists, the three sites were among the Second 100 IUGS Geological Heritage sites announced on Aug. 27 at the 37th International Geological Congress in South Korea. “These are the world’s best demonstrations of geologic features and processes,” the union said in a statement. “They are the sites of fabulous discoveries of the Earth and its history. They are sites that served to develop the science of geology.”

U research professor Marie Jackson, who mapped the three southern domes of the Henry Mountains for her doctoral dissertation in the 1980s, applauded the selection, which is a testament to G. K. Gilbert’s forward-thinking genius in the 19th century.

“This world was unexplored. These domes record raw geologic processes that were here for the viewing,” she said.

Jackson and Marjorie Chan, both professors in the Department of Geology and Geophysics, nominated the Utah sites and compiled descriptions for the IUGS geoheritage catalog. The MSc thesis of their former U graduate student Winston Seiler is devoted to The Wave.

How Harmful is Great Salt Lake Dust? U Scientists Investigate

September 18, 2024

Researchers from the University of Utah, including atmospheric scientist Kevin Perry and biologist Michael Werner, are attempting to get a handle on this question and the latest findings are concerning.

Sediments in the lake’s exposed playa are potentially more harmful than other major dust sources affecting the Wasatch Front’s air quality, according to a study published online recently in the journal Atmospheric Environment.

NBC News Dust researcher Kevin Perry poses with his fat bike and a PI-SWERL machine, which can measure wind erosion and dust emission.
Photo credit: Evan Bush

“You’re talking about a very large dust source located next to a very large population, and you’ve got elevated levels of manganese, iron, copper and lead. Lead is a concern for developmental reasons,” said senior author Kerry Kelly, a professor of chemical engineering. “Manganese, iron and copper, these are transition metals and are known to be very irritating to your lungs. Once you get irritation, that can lead to this whole inflammatory response. And that’s part of the problem with particulate matter and it’s adverse health effects like asthma.”

Another recent study led by sociology professor Sara Grineski found dust from the lakebed disproportionately affects disadvantaged neighborhoods in Salt Lake County.

In a separate forthcoming study led by U biologist Michael Werner’s lab, another team of researchers characterized levels of toxic metals deposited in submerged lakebed sediments sampled during the lake’s record low-water year of 2021, noting how these levels have changed since the years of Utah’s mining era.

To conduct the published study, Kerry Kelly’s lab, which specializes in air quality, teamed up with researchers in the U’s College of Science. They examined previously collected sediment samples from the Great Salt Lake, comparing them with sediments from other dust sources in the Great Basin, namely Sevier Lake, Fish Springs Lake and West Desert in western Utah and Tule Lake in northeastern California. These places are known to contribute to dust pollution reaching Salt Lake City.

In recent years, co-author Kevin Perry, a professor of atmospheric sciences, has systematically gathered exposed lakebed sediments, logging hundreds of miles on a bike. His prior research has identified “hotspots” on the playa that appear to be enriched with potentially toxic elements.

Honoring fallen soldiers: How science is using teeth to bring families closure

September 16, 2024

Even without a name, fingerprints, or facial features, our history leaves indelible marks on us, locked in the atoms of the toughest structures in our bodies: the enamel of our teeth. Subtle differences in tooth chemistry could help determine the identity of fallen soldiers and other human remains—if we can learn to read that history.

Gabe Bowen, the lead researcher for the FIND-EM project, takes a groundwater sample from a well. Credit: Bowen Lab.

Now, a collaboration between geography and dentistry researchers aims to find ways to map a person’s remains to the region where they grew up, based on slight differences in tooth enamel that are determined by the composition of local tap water.

While the researchers’ immediate goal is to help identify fallen soldiers, the project has the potential to strengthen the field of forensic investigation as a whole, according to Gabe Bowen, PhD, professor of geology and geophysics at the University of Utah and the lead on the project. “The ultimate goal is to produce a resource that will be very broadly useful,” Bowen says. “Cold cases, border crossers, humanitarian crises—any situation where we end up with individuals of unknown identity.”

The molar code:

To match someone’s teeth to where they grew up, the researchers are amassing a database of teeth donated by volunteers nationwide and comparing their enamel composition to groundwater data. They’re using wisdom teeth, which are commonly removed in modern dental care.

“I think it’s beautiful that in the natural progression of people’s treatment, we would be removing these teeth anyway,” says Michael Bingham, clinical research coordinator in the School of Dentistry at the University of Utah. “We can take something that would, in theory, be discarded, and use it to do this beautiful project of reuniting families with their service members’ remains.”

While the researchers need more tooth donors to get a comprehensive map, their results so far are promising.

College of Science

Climate change fueling more severe wildfires in California

Climate change fueling more
severe wildfires in California

Wildfires continue to damage California’s forests as human-driven climate change amplifies their impacts.

Exploring the Cosmic Unknown

Exploring the cosmic unknown with the Dark Energy Spectroscopic Instrument

Although the Dark Energy Spectroscopic Instrument sounds like something used at Hogwarts to practice wizardry, it is very much something based in real science.

A dino-mite addition to SLC International Airport

A dino-mite addition to SLC International Airport

What’s more exciting than a shortcut to the B-Gates? An Allosaurus at the airport!

From the Late Jurassic to Concourse B

Bringing together minds and resources for a greener tomorrow

Bringing together minds and resources for
a greener tomorrow

From the headwaters of the Wasatch to the threatened Great Salt Lake, Utah is rich in beauty, environmental opportunities, and stories of sustainability innovation.

Utah’s Natural Wonders: 3 New Geoheritage Sites

Utah's Natural Wonders: 3 New Geoheritage Sites

The International Commission on Geoheritage just named three locations in Utah as part of the Second 100 IUGS Geological Heritage Sites.

New models shed light on sea ice dynamics

New models shed light on sea ice dynamics

Polar sea ice is ever-changing. It shrinks, expands, moves, breaks apart, reforms in response to changing seasons, and rapid climate change.

A tale of two studies, one north and one south

How special is the Milky Way Galaxy?

How special is the Milky Way Galaxy?

A 'saga' about 101 galaxies like the Milky Way and their companions

An outlier galaxy?

Why do galaxies stop forming stars?

Gift to the astronomy community

U Scientists Nominate Iconic Utah Sites as Global Geoheritage Locations

U Scientists Nominate Iconic Utah Sites
as Global Geoheritage Locations

In 1875, Grove Karl Gilbert laid eyes on Utah’s remote and recently named Henry Mountains, and was fascinated by the “deep carving of the land which renders it so inhospitable to the travel and the settler, [but] is to the geologist a dissection which lays bare the very anatomy of the rocks.”

How Harmful is Great Salt Lake Dust? U Scientists Investigate

How Harmful is Great Salt Lake Dust?
U Scientists Investigate

As Utah’s Great Salt Lake shrinks, exposing more of its playa, concerns grow about the dust the dry lakebed emits. But scientists lack the data to fully understand what pollutants are present in these airborne sediments.

Honoring fallen soldiers: How science is using teeth to bring families closure

Honoring fallen soldiers: How science is using teeth to bring families closure

More than 80,000 American service members remain missing from previous wars, most from World War II. When remains are found, their age often makes identification difficult—but not impossible.

The molar code: