The ties that bind

The soils in many iconic Australian landscapes, like the outback and deserts, are colored red by an abundant mineral known as goethite. This mineral tends to lock away trace metals over time, according to research from Washington University in St. Louis
Photo Credit: Nathan March

Trace metals are nutrient elements, like zinc, that animals and plants need in small amounts to function properly. Animals generally get trace metals in their diets or through environmental exposures, while plants take their trace minerals up from soil. If we get too little, we may experience a deficiency, but the opposite can also be true: too much of a trace metal can be toxic.

Scientists believe that up to 50% of the trace metals in soils and urban environments may be bound to the surfaces of mineral grains — rendering the trace metals essentially unavailable for consumption or exposure. Researchers at Washington University in St. Louis wondered what holds them in place.

“When minerals bind trace metals, we often assume that they act like a sponge,” said Jeffrey G. Catalano, a professor of earth, environmental and planetary sciences and the director of environmental studies in Arts & Sciences. “But sometimes, they bind trace metals and won’t let them go. That is great when they are contaminants, but bad when they are serving as micronutrients.”

In a study published in the journal Environmental Science & Technology, Catalano and Greg Ledingham, a PhD candidate in his laboratory, discovered that a common mineral called goethite — an iron-rich mineral that is abundant in soils that cover the Earth — tends to incorporate trace metals into its structure over time, binding the metals in such a way that it locks them out of circulation.

Satellites unveil the size and nature of the world’s coral reefs

A satellite photo from the Allen Coral Atlas showing shallow coral reefs off Fiji
Image Credit: Courtesy of Allen Coral Atlas

University of Queensland-led research has shown there is more coral reef area across the globe than previously thought, with detailed satellite mapping helping to conserve these vital ecosystems.

Dr Mitchell Lyons from UQ’s School of the Environment, working as part of the Allen Coral Atlas project, said scientists have now identified 348,000 square kilometers of shallow coral reefs, up to 20-30 meters deep.

“This revises up our previous estimate of shallow reefs in the world’s oceans,” Dr Lyons said.

“Importantly, the high-resolution, up-to-date mapping satellite technology also allows us to see what these habitats are made from.

“We’ve found 80,000 square kilometers of reef have a hard bottom, where coral tends to grow, as opposed to soft bottom like sand, rubble or seagrass.

Riverine fish numbers increase amidst environmental challenges

Surprising trends in the abundance and species richness of riverine fish across the globe have been unveiled in a new study.
Photo Credit: Brandon

A new study, conducted by scientists at the University of Sheffield, has found a significant increase in the number and diversity of riverine fish species across the planet over the past 30 years

Contrary to conventional expectations, increases in fish species that live in rivers are concentrated in the most degraded areas

Although researchers found positive trends in riverine fish communities, a surge in the prevalence of non-native species poses a threat to the delicate balance of native fish

Surprising trends in the abundance and species richness of riverine fish across the globe have been unveiled in a new study. 

Until now, it was a common scientific belief that increases in species richness and abundance in freshwater ecosystems were as a result of the recent improvement of water quality in historically industrialized regions.

Frequency of U.S. blizzards may decline in coming decades

Vehicles in ditches and medians. Nights without power and heat. Injuries suffered. Lives lost.
Photo Credit: Shawn Dearn

For those in the Heartland, where the frying pan of summer gives way to the snow globe of winter, the scenes of a blizzard are familiar for their frequency. Of the nearly 13,000 U.S. blizzards documented between 1996 and 2020, more than 10,000 struck the northern Plains and Upper Midwest.

But the average number of blizzards could decline amid the lighter snowfalls and milder winds of coming decades, says a first-of-its-kind study from the University of Nebraska–Lincoln.

With help from the same models used by the Intergovernmental Panel on Climate Change, Nebraska’s Liang Chen is predicting a decrease in U.S. blizzards through the end of the 21st century. Chen recently presented the findings at the 104th annual meeting of the American Meteorological Society.

“Blizzards have a huge impact on a lot of our daily life — infrastructure, transportation,” said Chen, assistant professor of Earth and atmospheric sciences at Nebraska. “In terms of planning for climate change, people want to know: In the future, how will these blizzards change because of the warming climate?

“But there is no study looking at how they will change in the future, based on climate simulations. The major reason is: It’s hard to quantify.”

When the global climate has the hiccups

This chamber has the size of a football pitch and is located deep inside the cave.
Photo Credit: University of Basel, Dominik Fleitmann

Climate changes usually happens over long periods of time, but during the last glacial period, extreme fluctuations in temperature occurred within just a few years. Researchers at the University of Basel have now been able to prove the phenomenon also occurred during the penultimate glacial period.

In recent geological history, the so-called Quaternary period, there have been repeated ice ages and warm periods. Researchers are able to determine past climate variability from the composition of climate records. In the case of the last glacial period 100,000 years ago, ice cores from Greenland in particular provide researchers with detailed data.

For example, Greenland ice cores show that there were repeated rapid increases in temperature. “We are talking about increases of 5 to 10 degrees within 30 to 40 years on average in the case of Europe. A Neanderthal would have experienced increases in the average temperature of several degrees over the course of their life,” explains Prof. Dominik Fleitmann, Professor of Quaternary Geology at the University of Basel. He calls the phenomena “climate hiccups”.

These Dansgaard-Oeschger events are well documented for the last glacial period, but the climate records from Greenland only cover the last 120,000 years. It was therefore previously unknown whether these Dansgaard-Oeschger events also occurred during the penultimate glacial period 135,000 to 190,000 years ago. Frederick Held, a PhD candidate in Fleitmann’s research group, was able to show that Dansgaard-Oeschger events also occurred during the penultimate glacial period using isotopic measurements on stalagmites. He is the lead author of the study which was published in the scientific journal Nature Communications.

Western Cascades landscapes in Oregon historically burned more often than previously thought

Students, tribal members and others visit the study site.
Photo Credit: Sarah Altemus Pope of the Southern Willamette Forest Collaborative.

Forests on the west slope of Oregon’s Cascade Range experienced fire much more often between 1500 and 1895 than had been previously thought, according to new research by scientists at Oregon State University.

The findings provide important insight, the authors say, into how landscapes might adapt to climate change and future fire regimes.

James Johnston of the OSU College of Forestry led the study, which was published in Ecosphere.

“Wildland fire is a fundamental forest ecosystem process,” he said. “With temperatures rising and more and more area burning, we need to know as much as we can about the long-term variability in fire.”

Johnson and collaborators at Oregon State, the University of Oregon and the U.S. Forest Service gathered tree ring data at 16 sites in the southern part of the Willamette National Forest, in the general vicinity of Oakridge.

Trees form scars after cambial cells are killed by wildfire heat, he said. These scars are partially or completely covered by new tissue as a tree grows, and tree rings tell the story of when the fire exposure occurred.

Nanoscale Analysis Provides Key Answers for Modeling Mineralization in Basalt

A methodology on resolving nanoscale processes during carbon mineralization—discovered and led by Pacific Northwest National Laboratory Post Doctoral Researcher Xiaoxu Li and Chemist Emily Nienhuis—provides insight into the previous knowledge gaps needed for accurate reservoir models.  
Composite Credit: Mike Perkins | Pacific Northwest National Laboratory

Removing carbon dioxide (CO2) from industrial emissions and from the atmosphere and then safely storing it into the Earth’s deep subsurface is becoming increasingly essential to meeting decarbonization goals and preserving a livable planet.

Pacific Northwest National Laboratory (PNNL) scientists discovered how to store supercritical CO2—carbon dioxide in its fluid state—in basalt reservoirs safely and permanently. This process is called geologic carbon sequestration, or carbon mineralization. But for the technology to be deployed commercially in the United States a Class VI well permit must first be attained.

“In order to apply for and be issued this permit, there has to be what is called a reservoir model for us to understand the fate and behavior of the injected CO2,” said PNNL Chemist Emily Nienhuis. “In other words, if we inject x amount of CO2 into a reservoir, where does it go? And how long does it take to mineralize or become rock?”

Ural Scientists Assessed How Vegetation Changes in the Mountains

As scientists explain, the woody vegetation of high mountains is a sensitive indicator of climate change.
 Photo Credit: Pavel Yelfimov

Specialists of the Ural Carbon test site, researchers from the Ural Federal University (UrFU) with colleagues from the Ural State Forestry Technical University, have proposed a methodology for automated mapping of high mountain woody vegetation. The methodology is based on the comparison of data from archival aerial images and modern satellite images, RIA Novosti reported. The work of researchers will help to objectively assess the peculiarities of the appearance of new trees on unforested territory depending on the influence of the environment. The description of the methodology is published in the journal Forests.

"Woody vegetation of high mountains, near its upper limit of growth, is a sensitive indicator of climate change. Therefore, mountain ranges in different regions of the Earth are considered as areas for studying the early vegetation response to regional climate change. The aim of our work was twofold. The first part involves demonstrating an effective method of automated mapping of vegetation cover units: forest, sparse woodland, open stand, and tundra with freestanding trees developed by us, and to analyze changes occurring in plant communities under the conditions of modern climate warming near the upper limit of tree growth. The second part includes evaluating the efficiency of the method on the example of assessing the expansion of Siberian larch into mountain tundra in the Polar Urals over the past 50 years," explains Valery Fomin, Vice-Rector for Research and Innovation at Ural State Forestry Technical University and researcher at UrFU.

Octopus DNA solves mystery of ice sheet’s past

Octopus, probably Pareledone species, from 500m depth on the Bellingshausen Sea continental shelf.
Photo Credit: British Antarctic Survey

Scientists, including from British Antarctic Survey, have used octopus DNA to discover that the West Antarctic Ice Sheet (WAIS) likely collapsed during the Last Interglacial period around 120,000 years ago – when the global temperatures were similar to today.

This provides the first empirical evidence that the tipping point of this ice sheet could be reached even under the Paris Agreement targets of limiting warming to 1.5-2oC.

The study, published in the journal Science, was led by Professor Jan Strugnell, Chief Investigator, and Dr Sally Lau, Postdoctoral Research Fellow from ARC Securing Antarctica’s Environmental Future at James Cook University.

Octopus, probably Pareledone species, from 500m depth on the Bellingshausen Sea continental shelf. BAS.

Common insect species are suffering the biggest losses

The invasive Asian Ladybeetle (Harmonia axyridis)
Photo Credit: Melani Marfeld

Insect decline is being driven by losses among the locally more common species, according to a new study published in Nature. Led by researchers at the German Centre for Integrative Biodiversity Research (iDiv) and the Martin Luther University Halle-Wittenberg (MLU), the meta-analysis of 923 locations around the world notes two significant trends: Species with the most individuals are disproportionately decreasing in number, and no other species have increased to the high numbers previously seen. This likely explains the frequent observation that there are fewer insects around now than ten, twenty, or thirty years ago.

Researchers at iDiv looked at long-term trends of land-based insects, such as beetles, moths, and grasshoppers, and found that decreases in the number of the formerly most common species have contributed most to local insect declines. Common or abundant insect species are those species that are locally found in the highest numbers, but which species these are differ among locations. The study’s findings challenge the idea that changes in insect biodiversity result from rarer species disappearing.

The study follows the recent sounding of alarm bells about insect loss, as researchers note dramatic declines in the total number of insects in many parts of the world. However, little is known about the general trends among locally rare and abundant species over long periods. "It was obvious this needed exploring," says Roel van Klink, lead author of the study and senior scientist at iDiv and MLU. "We had to know whether observations about declines in total abundances of insects differed among common and rare species, and how this translated into changes in the overall insect diversity."

Gravity data could reveal underwater volcanoes with high potential for devastating eruptions

This looping video shows an umbrella cloud generated by the underwater eruption of the Hunga Tonga-Hunga Ha’apai volcano on Jan. 15, 2022. The GOES-17 satellite captured the series of images that also show crescent-shaped shock waves and lightning strikes.
Video Credit: NASA Earth Observatory image by Joshua Stevens using GOES imagery courtesy of NOAA and NESDIS

New research led by Carnegie’s Hélène Le Mével reveals new details about the system of magma chambers under the Hunga volcano, both before and after its disastrous 2022 eruption. The team’s findings, published last week in Science Advances, demonstrate a new method for probing submarine volcanoes for their potential to cause similar damage.

The eruption came at the end of a month-long period of volcanic unrest, following a seven-year hiatus for the volcano—devastating the Kingdom of Tonga islands and causing a global tsunami, an unprecedented amount of volcanic lightning, and perturbations in the upper atmosphere. . It was the largest explosive eruption recorded since Pinatubo in 1991.

“Although we have a wealth of data about the Hunga eruption’s effects both locally and globally, we know very little about its subsurface structure,” Le Mével explained.

Scientists uncover link between the ocean’s weather and global climate

Oceanic weather systems (mesoscale eddies) from data overlaid with atmospherically driven climate-scale currents (black lines), which can be extracted with a coarse graining technique developed in the lab of Hussein Aluie. The image reveals how these ocean weather systems are energized (red) or weakened (blue) when interacting with climate-scales, which follows a pattern mirroring the global atmospheric circulation.
Illustration Credit: Benjamin Storer

Using mechanical rather than statistical analysis, the team offers a new framework for understanding the climate system.

An international team of scientists has found the first direct evidence linking seemingly random weather systems in the ocean with climate on a global scale. Led by Hussein Aluie, an associate professor in the University of Rochester’s Department of Mechanical Engineering and staff scientist at the University’s Laboratory for Laser Energetics, the team reported their findings in Science Advances.

The ocean has weather patterns like what we experience on land, but on different time and length scales, says lead author Benjamin Storer, a research associate in Aluie’s Turbulence and Complex Flow Group. A weather pattern on land might last a few days and be about 500 kilometers wide, while oceanic weather patterns such as swirling eddies last three to four weeks but are about one-fifth the size.

Uncovering the role of beta diversity in ecosystems

Karen Castillioni observes beta diversity in a prairie habitat.
Photo Credit: College of Biological Sciences

As climate change progresses, scientists want to better understand how species interact across habitats to preserve diversity. Key to these efforts is the concept of beta diversity, which explores species that thrive exclusively in specific habitats. The University of Minnesota's Cedar Creek Ecosystem Science Reserve in East Bethel is an ideal place to study beta diversity because it gives researchers access to many distinct habitats in one place. 

Karen Castillioni, a postdoctoral research associate in the College of Biological Sciences, along with Associate Professor Forest Isbell, wanted to know how beta diversity affects plant biomass, the total mass of living plants in a given area. Plant biomass is crucial for various ecological and environmental functions, including carbon sequestration and supporting food webs.

During the first phase of an experiment at Cedar Creek called BetaDIV, the researchers looked at five habitats: oak savanna, where bur oak tree dominates; coniferous forest, where white pine dominates; deciduous forest, where red maple dominates; bog, where tamarack dominates; and an old grassland where big bluestem dominates.

Using a fiber optic cable to study Arctic seafloor permafrost

A permafrost-created pingo or “ice pimple” in the North Slope of Alaska. Scientists from Sandia National Laboratories have been using a fiber optic cable to study permafrost in the Arctic seafloor to improve the understanding of global climate change.
Photo Credit: Courtesy of Sandia National Laboratories

The Arctic is remote, with often harsh conditions, and its climate is changing rapidly — warming four times faster than the rest of the Earth. This makes studying the Arctic climate both challenging and vital for understanding global climate change.

Scientists at Sandia National Laboratories are using an existing fiber optic cable off Oliktok Point on the North Slope of Alaska to study the conditions of the Arctic seafloor up to 20 miles from shore. Christian Stanciu, project lead, will present their latest findings on Friday, Dec. 15 at AGU’s Fall Meeting in San Francisco.

Their goal is to determine the seismic structure of miles of Arctic seafloor. Using an emerging technique, they can spot areas of the seafloor where sound travels faster than on the rest of the seafloor, typically because of more ice. They have identified several areas with lots of ice, said Stanciu, a Sandia geophysicist.

The scientists also used the cable to determine temperatures over the stretch of seafloor and monitored temperature changes over seasons. "This data, unlike any collected before, was inserted into a computer model to infer the distribution of submarine permafrost," said Jennifer Frederick, a computational geoscientist.

“One of the innovations of this project is that we can now use a single fiber to get acoustic and temperature data,” Stanciu said. “We developed a new system to remotely collect both types of data using one fiber strand. We’re getting some interesting results.”

Custom software speeds up, stabilizes high-profile ocean model

The illustration depicts ocean surface currents simulated by MPAS-Ocean.
Illustration Credit: Los Alamos National Laboratory, E3SM, U.S. Dept. of Energy

On the beach, ocean waves provide soothing white noise. But in scientific laboratories, they play a key role in weather forecasting and climate research. Along with the atmosphere, the ocean is typically one of the largest and most computationally demanding components of Earth system models like the Department of Energy’s Energy Exascale Earth System Model, or E3SM.

Most modern ocean models focus on two categories of waves: a barotropic system, which has a fast wave propagation speed, and a baroclinic system, which has a slow wave propagation speed. To help address the challenge of simulating these two modes simultaneously, a team from DOE’s Oak Ridge, Los Alamos and Sandia National Laboratories has developed a new solver algorithm that reduces the total run time of the Model for Prediction Across Scales-Ocean, or MPAS-Ocean, E3SM’s ocean circulation model, by 45%. 

The researchers tested their software on the Summit supercomputer at ORNL’s Oak Ridge Leadership Computing Facility, a DOE Office of Science user facility, and the Compy supercomputer at Pacific Northwest National Laboratory. They ran their primary simulations on the Cori and Perlmutter supercomputers at Lawrence Berkeley National Laboratory’s National Energy Research Scientific Computing Center, and their results were published in the International Journal of High Performance Computing Applications.

Lightning, camera, gamma ray!

Lightning captured with the highspeed camera at 40,000 frames per second.
Photo Credit: Rasha Abbasi

In September 2021, an unprecedented thunderstorm blew across Utah’s West Desert. Lightning from this storm produced at least six gamma ray flashes that beamed downward to Earth’s surface and activated detectors at the University of Utah-led Telescope Array. The storm was noteworthy on its own—the array usually clocks one or two of the lightning-triggered gamma rays per year—but recent upgrades led to a new observation by the Telescope Array scientists and their lightning collaborators.

For the first time ever, they captured video footage of lightning-triggered downward terrestrial gamma-ray flashes (TGFs). A special camera running at 40,000 frames per second gave an unprecedented look at how gamma rays burst downwards to the Earth’s surface from cloud-to-ground lightning strikes. They found that not only were multiple gamma rays produced at later lightning stages than previously thought, but the rays were also associated with a pulse of optical light that had never been recorded.

“This is an important step in lightning research that could lead us to the physics producing these downward gamma rays,” said lead author Dr. Rasha Abbasi, now an assistant professor of physics at Loyola University Chicago. Abbasi began the research on TGFs as a postdoctoral scholar at the University of Utah.

Tropical ice cores offer deeper insights into Earth’s temperature record

Ice cores recovered from tropical locations act as unique records of Earth's complex climate history.
Huascarán, Huaraz, Perú
Photo Credit: Jean Simón

A new study suggests ice recovered from high tropical mountains can reveal key insights about Earth’s past climate changes.  

Led by scientists at The Ohio State University, the study showed that oxygen-stable isotope records stored in tropical mountain glacier ice cores can be used to provide scientists with a distinct paleoclimate history of the planet’s middle and upper troposphere. By combining ice core proxy records, paleoclimate simulations and modern satellite measurements and comparing the results to those from previous climate models, they found that the temperature in this region of the atmosphere cooled by 7.35 degrees Celsius during the Earth’s glacial period, which for many researchers illuminates new theories about climate dynamics throughout the ages.  

“Typically, you need hundreds of pieces of data to construct a record of global mean temperature,” said Zhengyu Liu, lead author of the study and a professor of geography at The Ohio State University. “It turns out, in that region in the tropics and at that height, you can use just one, and it’s very consistent with many other independent constructions available, which rely primarily on sea surface temperature proxies.” 

New Insights into Ecosystem Functions

The mastermind behind the new statistical method: mathematician and statistician Anne Chao from National Tsing Hua University in Taiwan. Here she is in the university forest of the University of Würzburg on an experimental test plot.
Photo Credit: Simon Thorn/JMU

A DFG research group led by the University of Würzburg has developed a method that makes it possible to analyze the relationship between biodiversity within and between ecosystems and the multifunctionality of entire landscapes.

Ecosystems fulfil a number of vital tasks: They store carbon, clean polluted water, pollinate plants and so on. How well an ecosystem can fulfil these tasks depends largely on its biodiversity, i.e. the variety of plants, animals and microorganisms that live in it. Until now, scientists have only been able to understand the exact nature of this relationship at a local level, for example in relation to individual forest areas, meadows and ponds. The DFG (German Research Foundation) research group BETA-FOR, led by the University of Würzburg (JMU), has now succeeded in developing a statistical method that for the first time can also analyze the contributions of biodiversity between local ecosystems to the multifunctionality of entire landscapes.

Aquatic Insects in Restored Streams Need More Rocks to Lay Their Eggs

A caddisfly egg mass sits on the underside of a protruding rock.
Photo Credit: Brad Taylor, NC State University.

Likening it to providing more runways at busy airports, researchers at North Carolina State University found in a new study that adding protruding rocks to restored streams can help attract female aquatic insects that lay their eggs on the rock bottoms or sides.

More eggs that hatch into larval insects is great news for stream restoration because the re-establishment of organisms, such as insects, is often slower than expected in restored streams, says Brad Taylor, associate professor of applied ecology at NC State and corresponding author of a paper describing the research. A thriving population of stream insects generally portends good water quality, overall stream health, and provides food for fish, amphibians, reptiles, and even birds, he adds.

Most stream insects use rocks protruding above the water as runways to land on, then crawl underwater and attach their eggs to the underside of the rocks. Because restored streams sometimes fail to regain their abundance of aquatic insects even decades following restoration, researchers were interested in testing whether increasing egg-laying habitat the rock landing areas would increase the abundance and diversity of insect eggs and larvae.

Taylor and NC State graduate student Samantha Dilworth selected 10 restored streams in northwestern North Carolina and added protruding rocks gathered near the streams to five of them; the other five restored streams did not receive additional rocks.

Cutting-edge Biodiversity Models Will Help Assess Nature's Vital Contributions to People

Photo Credit: Pixabay

People depend on nature in a multitude of ways. Crop pollination, pest management, storm buffering, and carbon capturing are all part of nature's contributions to people (NCP). But these contributions are subject to change - species that make vital contributions may migrate or even go extinct due to climate change or habitat loss. Forecasting these changes is challenging, but also essential to ensure that humans are adequately prepared to respond.

Part of what makes this so challenging is that current NCP estimates typically rely on data incorporating the physical environment and omit information on species. Given that biodiversity is a cornerstone of NCP, many scientists recognize that biodiversity information can help us better assess the current and future state of NCP.

In a new opinion paper published in Trends in Ecology and Evolution, lead author Jamie M. Kass, associate professor and head of the Macroecology Lab at Tohoku University's Graduate School of Life Sciences, and an international team of colleagues argue that recent advances in biodiversity modeling and mapping have great potential for improving NCP estimates.