Six-million-year-old ice discovered in Antarctica offers unprecedented window into a warmer Earth

Raising the Foro Drill, Allan Hills, Antarctica. 2022-2023.
Photo Credit: Julia Marks Peterson, COLDEX.

A team of U.S. scientists has discovered the oldest directly dated ice and air on the planet in the Allan Hills region of East Antarctica.

The 6-million-year-old ice and the tiny air bubbles trapped inside it provide an unprecedented window into Earth’s past climate, according to a new study published today in the Proceedings of the National Academy of Sciences.

The oldest ice sample from Allan Hills dated by researchers clocks in at 6 million years, from a period in Earth’s history where abundant geological evidence indicates much warmer temperatures and higher sea levels compared to today.

What Is: A Greenhouse Gas

Image Credit: Skeptical Science
(CC BY 4.0)

A greenhouse gas (GHG) is a constituent of the atmosphere that absorbs and emits longwave radiation, impeding the flow of heat from the Earth's surface into space. This process is the physical basis of the greenhouse effect, formally defined as "the infrared radiative effect of all infrared absorbing constituents in the atmosphere," which includes greenhouse gases, clouds, and some aerosols.

It is essential to distinguish between two distinct phenomena:

The Natural Greenhouse Effect: This is the baseline, life-sustaining process. Greenhouse gases, particularly water vapor and carbon dioxide, are a crucial component of the climate system. Without this natural insulating layer, the heat emitted by the Earth would "simply pass outwards... into space," and the planet's average temperature would be an uninhabitable -20°C.

The Enhanced Greenhouse Effect: This refers to the anthropogenic, or human-caused, intensification of the natural effect. The accumulation of greenhouse gases in the atmosphere, primarily from the burning of fossil fuels and other industrial and agricultural activities, is trapping additional heat, driving the rapid warming of the planet's surface and lower atmosphere.

The term "greenhouse" is a persistent and somewhat misleading analogy. A physical greenhouse primarily works by a mechanical process: its glass walls stop convection, preventing the warm air inside from rising and mixing with the colder air outside. The Earth's greenhouse effect is not a physical barrier; it is a radiative one. Greenhouse gases do not trap air. Instead, they absorb outgoing thermal radiation and re-radiate a portion of it back toward the surface, slowing the planet's ability to cool itself. This radiative mechanism, not a convective one, is how a relatively tiny fraction of the atmosphere can have a planet-altering effect.

Coronal mass ejections at the dawn of the solar system

Artist's depiction of a coronal mass ejection from EK Draconis. The hotter and faster ejection is shown in blue, while the cooler and slower ejection is shown in red.
Image Credit: National Astronomical Observatory of Japan

Down here on Earth we don't usually notice, but the Sun is frequently ejecting huge masses of plasma into space. These are called coronal mass ejections (CMEs). They often occur together with sudden brightenings called flares, and sometimes extend far enough to disturb Earth's magnetosphere, generating space weather phenomena including auroras or geomagnetic storms, and even damaging power grids on occasion.

Scientists believe that when the Sun and the Earth were young, the Sun was so active that these CMEs may have even affected the emergence and evolution of life on the Earth. In fact, previous studies have revealed that young Sun-like stars, proxies of our Sun in its youth, frequently produce powerful flares that far exceed the largest solar flares in modern history.

Tropical rivers emit less greenhouse gases than previously thought

Lowland tropical rivers emit large quantities of greenhouse gases, with rates influenced by seasonal flooding.
Photo Credit: Jenny Davis

Tropical inland waters don’t produce as many greenhouse gas emissions as previously estimated, according to the results of an international study, led by Charles Darwin University and involving researchers from Umeå University.

The study, published in Nature Water, aimed to better understand greenhouse gas emissions in tropical rivers, lakes and reservoirs by collating the growing amount of observations from across the world’s tropics – including many systems that were previously less represented in global datasets.

Researchers from Umeå University played a key role in the work, estimating the surface area of rivers and contributing to the data analysis that underpins the study’s findings.

A New Study Indicates Forest Regeneration Provides Climate Benefits, but Won’t Offset Fossil Fuels

Forest regrowth after 5 years since agricultural abandonment near Pucallpa, Ucayali, Peru.
Photo Credit: Jorge Vela Alvarado, Universidad Nacional de Ucayali

When farmland is abandoned and allowed to return to nature, forests and grasslands naturally regrow and absorb carbon dioxide from the atmosphere—helping fight climate change. However, a new study in the journal Global Biogeochemical Cycles, led by scientists at Columbia University, reveals an important wrinkle in this story: these regenerating ecosystems also release other greenhouse gases that reduce some of their climate benefits. The good news? Even accounting for these other gases, letting land regenerate naturally still provides important climate benefits compared with keeping it in agriculture.

Lead author Savannah S. Cooley, a research scientist at NASA Ames Research Center and a recent PhD graduate of Columbia’s Ecology, Evolution and Environmental Biology program, and her team of co-authors analyzed data from 115 studies worldwide to understand how forests and grasslands affect the climate through three key greenhouse gases: carbon dioxide, methane and nitrous oxide. While previous research focused mainly on carbon dioxide absorption by growing trees, this study examined a more complete picture.

Each fossil fuel project linked to additional global warming

Photo Credit: Roman Khripkov

Individual fossil fuel projects can no longer be considered too small to matter according to new Australian research linking each new investment in coal and gas extraction with measurable increases in global temperatures.

Published in the Nature journal Climate Action, climate scientists from six Australian universities, including the University of Melbourne, have revealed findings that debunk claims individual fossil fuel projects have little impact on global warming.

The research led by the ARC Centre of Excellence for the Weather of the 21st Century focused on the Scarborough gas project in Northwest Australia. It found that the project alone is estimated to lead to an increase of approximately 0.00039°C in global temperature from 876 million tons of CO2 emissions.

University of Melbourne Associate Professor Andrew King from the School of Geography, Earth and Atmospheric Sciences explained that while 0.00039°C of additional warming may seem relatively small, its impacts on society and the environment are actually large.

“This degree of warming could expose over half a million people to unprecedented extreme heat,” Associate Professor King said.

What Is: El Niño, La Niña, and a Climate in Flux

Image Credit: Scientific Frontline / NOAA

The Planet's Most Powerful Climate Cycle

In 1997, a climatic event of unprecedented scale began to unfold in the tropical Pacific Ocean. Dubbed the "El Niño of the century," it triggered a cascade of extreme weather that reshaped global patterns for over a year. It unleashed devastating floods and droughts, sparked massive forest fires, decimated marine ecosystems, and crippled national economies. By the time it subsided in 1998, the event was estimated to have caused more than 22,000 deaths and inflicted over $36 billion in damages worldwide. Nearly two decades later, the powerful 2015-16 El Niño, supercharged by a background of long-term global warming, helped propel 2016 to become the hottest year on record and directly impacted the lives and livelihoods of over 60 million people.

These catastrophic events are not random acts of nature but manifestations of the planet's most powerful and influential climate cycle: the El Niño-Southern Oscillation (ENSO). This naturally occurring phenomenon is a periodic, irregular fluctuation of sea surface temperatures and atmospheric pressure across the vast expanse of the equatorial Pacific Ocean. At its heart are two opposing phases: El Niño ("The Little Boy" in Spanish), a significant warming of the ocean surface, and La Niña ("The Little Girl"), a countervailing cooling. Together with a neutral "in-between" state, they form a planetary-scale pendulum that swings irregularly every two to seven years, dictating patterns of drought and flood, storm and calm, across the globe.

Green Energy and Innovation Can Increase Greenhouse Gas Emissions

The introduction of renewable energy sources in developing Asian countries may lead to a short-term increase in greenhouse gas emissions.
Photo Credit: Nicholas Doherty

Scientists at Ural Federal University have found that the introduction of renewable energy sources (RES) and technological innovations in developing Asian countries can lead to a short-term increase in greenhouse gas emissions. The reason is the effect of rebound and insufficient effectiveness of regulatory systems. This calls into question the effectiveness of current measures to achieve the goals of the Paris Agreement, the researchers believe. They wrote on this topic in an article in the journal Energy Economics.

"In Asia, more efficient coal-fired power plants or cheaper solar energy can lower electricity prices, leading to increased energy consumption by industry and households in general. Although innovations reduce CO₂ emissions in the short term, they actually increase emissions in the medium and long term, as efficiency gains drive growth in industrial activity and energy demand. This is a classic rebound effect: efficiency stimulates economies of scale, negating the initial environmental benefits," explained Kazi Sohag, co-author of the paper and head of the UrFU Laboratory of Economic Policy and Natural Resources.

Clam shells sound warning of Atlantic ‘tipping point’

Ocean quahog shells.
Photo Credit Paul Butler

A study of clam shells suggests Atlantic Ocean currents may be approaching a “tipping point”.

Scientists studied records of quahog clams (which can live for over 500 years) and dog cockles – because shell layers provide an annual record of ocean conditions.

They studied these natural archives to understand long-term patterns in Atlantic Ocean currents such as the Atlantic Meridional Overturning Circulation (AMOC) and the subpolar gyre (SPG).

Recent studies have debated possible AMOC and SPG tipping points – transitions that would transform climate patterns. For example, AMOC collapse would have far-reaching global effects, from harsher winters in north-west Europe to shifts in global rainfall patterns, while a weakening of the SPG would be less catastrophic but still bring substantial impacts, including more frequent extreme weather in the North Atlantic region.

Rapid flash Joule heating technique unlocks efficient rare‑earth element recovery from electronic waste

The research team’s method uses flash Joule heating.
Photo Credit: Jeff Fitlow/Rice University.

A team of researchers including Rice University’s James Tour and Shichen Xu has developed an ultrafast, one-step method to recover rare earth elements (REEs) from discarded magnets using an innovative approach that offers significant environmental and economic benefits over traditional recycling methods. Their study was published in the Proceedings of the National Academy of Sciences Sept. 29, 2025.

Conventional rare earth recycling is energy-heavy and creates toxic waste. The research team’s method uses flash Joule heating (FJH), which rapidly raises material temperatures to thousands of degrees within milliseconds, and chlorine gas to extract REEs from magnet waste in seconds without needing water or acids. The breakthrough supports U.S. efforts to boost domestic mineral supplies.

“We’ve demonstrated that we can recover rare earth elements from electronic waste in seconds with minimal environmental footprint,” said Tour, the T.T. and W.F. Chao Professor of Chemistry, professor of materials science and nanoengineering and study corresponding author. “It’s the kind of leap forward we need to secure a resilient and circular supply chain.”

Turning Plastic Waste into Fuel

Ali Kamali, a doctoral candidate in chemical and biomolecular engineering, inspects a sample of liquid fuel created from plastics.
Photo Credit: Kathy F. Atkinson

Plastics are valued for their durability, but that quality also makes it difficult to break down. Tiny pieces of debris known as microplastics persist in soil, water and air and threaten ecosystems and human health. Traditional recycling reprocesses plastics to make new products, but each time this is done, the material becomes lower in quality due to contamination and degradation of the polymers in plastics. Moreover, recycling alone cannot keep pace with the growing volume of global plastic waste.

Now, a University of Delaware-led research team has developed a new type of catalyst that enhances conversion of plastic waste into liquid fuels more quickly and with fewer undesired byproducts than current methods. Published in the journal Chem Catalysis, the pilot-stage work helps pave the way toward energy-efficient methods for plastic upcycling, reducing plastic pollution and promoting sustainable fuel production.

“Instead of letting plastics pile up as waste, upcycling treats them like solid fuels that can be transformed into useful liquid fuels and chemicals, offering a faster, more efficient and environmentally friendly solution,” said senior author Dongxia Liu, the Robert K. Grasseli Professor of Chemical and Biomolecular Engineering at UD’s College of Engineering.

Methane production may increase as Arctic lakes warm

 

Fältarbete vid sjöar nära Abisko naturvetenskapliga station.
Photo Credit: Sofia Kjellman

A warmer and wetter climate makes lakes more productive – which in turn leads to more methane being released from sediments. A new study involving Umeå University shows that Arctic lakes may contribute even more to the greenhouse effect in the future.

Methane is more than 25 times stronger as a greenhouse gas than carbon dioxide. Arctic lakes account for a significant share of global methane emissions, but until now, knowledge about the processes in northern lakes has been limited. An international team of researchers from Norway, Sweden and Spain has now shown that methane production varies greatly between lakes and is closely linked to their characteristics.

The researchers investigated ten lakes on Svalbard and in the subarctic region of Scandinavia, three of them via the Abisko Scientific Research Station. They found that most methane production occurs in the top ten centimeters of lake sediments, where there is abundant organic matter and favorable conditions for microbes.

Sandy Seafloors: An Overlooked Source of Greenhouse Gas

Photo Credit: Walter Frehner

A new study reveals that methane can form in the upper layers of sandy seabeds — something that has taken scientists by surprise. Special microorganisms are at work, and the phenomenon may be happening along coastlines all over the world.  

Methane is a powerful greenhouse gas, produced in many natural environments by microorganisms.  

Until recently, scientists believed these microbes were intolerant of oxygen and could only survive in oxygen-free zones. But new research shows they can, in fact, persist in oxygenated environments — lying dormant until the oxygen disappears. That means an entirely new source of methane emissions has just been discovered.  

“We do not yet know how much methane these microbes are producing. That is the next big question. But we suspect the contribution is significant and widespread in sandy coastal zones. This is not something confined to a few isolated spots on the globe,” says Ronnie N. Glud, professor at the Department of Biology and an expert in biogeochemistry.  

Research yields eco-friendly way to separate, recycle refrigerants tied to climate crisis

Lead author Abby Harders, who earned her doctorate in chemical and petroleum engineering at the University of Kansas, now serves as head of research and development at Icorium Engineering, situated in KU’s Innovation Park.
Photo Credit: Max Jiang

A scholarly report in the journal Science Advances from researchers at the University of Kansas shows a new eco-friendly method for separating the chemicals found in common refrigerants for easier recycling at industrial scale.

“The motivation of this work is to enable separation of highly complex gaseous refrigerant mixtures,” said lead author Abby Harders, who performed the research as a KU doctoral student in the research group of co-author Mark Shiflett, Foundation Distinguished Professor of Chemical and Petroleum Engineering. “This effort has been driven by climate legislation phasing out certain hydrofluorocarbon (HFC) refrigerants.”

The paper's key innovation uses membranes — amorphous fluorinated polymers, to be specific — that efficiently isolate complex refrigerant mixtures. Other separation methods, like distillation, are less effective because of the complex composition of the mixtures. Harders said the membranes are fabricated to allow some gases to pass through while restricting others — resulting in effective purification.

To demonstrate the technology could scale to industrial viability, the team — including many associated with KU’s Wonderful Institute for Sustainable Engineering — developed a custom-coating process to create submicron coatings on the membrane’s porous supports, creating composite hollow fibers. The results show a functional prototype, proving the technology’s usefulness to firms engaged in refrigerant recovery and reuse. 

Mount Rainier White-Tailed Ptarmigan Finally Receives a ‘Threatened’ Species Designation

An adult Mount Rainier white-tailed ptarmigan in brown summer plumage. Its feathers change seasonally—white in the winter, white and brown in the spring. Its tail remains white year-round.
Photo Credit: Pete Plage/USFWS

In July, the Mount Rainier white-tailed ptarmigan was officially listed as threatened by the U.S. Fish and Wildlife Service (FWS) under the Endangered Species Act (ESA), 14 years after the Center for Biological Diversity first petitioned for its listing. This designation is meant to help preserve the bird, whose survival depends on the glaciers of the Cascade Mountains of Washington State and British Columbia. It also reflects the complex challenges that alpine-adapted birds face in a warming world.

With its feathered, snowshoe-like feet that allow it to walk on high mountain terrain and its seasonal plumage that provides camouflage year-round, Mount Rainier white-tailed ptarmigans are adapted to high elevation regions above the treeline. They are frequently spotted in areas with mixed rock, snow and alpine plants. Their diet consists of twigs, leaves, buds and seeds of alpine tundra vegetation that only grow in treeless, cold and dry mountainous regions that receive critical moisture from spring snowmelt and summer glacier runoff.

Warming temperatures are accelerating glacier retreat and endangering the bird’s habitat: glaciers in the North Cascades shrunk 56 percent between 1900 and 2009. Mauri Pelto, director of the North Cascade Glacier Climate Project, told GlacierHub that ptarmigans are often spotted along the Shuksan and Ptarmigan Ridges near Mount Baker. In a study, Pelto found that seven of the 13 glaciers along those ridges have disappeared since the mid-1980s. Retreating glaciers risk reduced soil water availability for tundra vegetation and long-term habitat loss associated with warming temperatures.

Ancient Antarctic ice loss offers insights into future climate scenarios

Photo Credit: University of Cambridge / British Antarctic Survey.

Scientists from the University of Cambridge and British Antarctic Survey have used ice core records to draw new conclusions about how Antarctica was affected by increased global temperatures over 100,000 years ago. The new paper, published today in the journal Nature, shows that large parts of the West Antarctic Ice Sheet were lost, contributing to significant sea level rise. However, the data also suggests that the nearby Ronne Ice Shelf – which climate models project could be lost under future warming scenarios – survived this period of global heating.

Greenhouse gas emissions are warming the Earth at an unprecedented speed and scale. While anthropogenic warming has no direct historical parallel, warm episodes in Earth’s history can offer clues to the future.

A team of ice core scientists, led by Eric Wolff from Cambridge University, wanted to find out what happened to the West Antarctic Ice Sheet during the Last Interglacial, when the polar regions were about 3°C warmer than present and sea levels were significantly higher. This period of Earth’s history is considered comparable to conditions we might see within decades.

Increased wildfire activity may be a feature of past periods of abrupt climate change, study finds

A new study investigating ancient methane trapped in Antarctic ice suggests that global increases in wildfire activity likely occurred during periods of abrupt climate change throughout the last Ice Age.

The study, just published in the journal Nature, reveals increased wildfire activity as a potential feature of these periods of abrupt climate change, which also saw significant shifts in tropical rainfall patterns and temperature fluctuations around the world.

“This study showed that the planet experienced these short, sudden episodes of burning, and they happened at the same time as these other big climate shifts,” said Edward Brook, a paleoclimatologist at Oregon State University and a co-author of the study. “This is something new in our data on past climate.”

The findings have implications for understanding modern abrupt climate change, said the study’s lead author, Ben Riddell-Young, who conducted the research as part of his doctoral studies in OSU’s College of Earth, Ocean, and Atmospheric Sciences.

“This research shows that we may not be properly considering how wildfire activity might change as the climate warms and rainfall patterns shift,” said Riddell-Young, who is now a postdoctoral scholar at the Cooperative Institute for Research in Environmental Sciences at the University of Colorado, Boulder.

New protective coating can improve battery performance

Mario El Kazzi and his team have developed a cathode surface coating that enables operating voltages of up to 4.8 volts.
Photo Credit: © Paul Scherrer Institute PSI/Mahir Dzambegovic

A research team at the Paul Scherrer Institute PSI has developed a new sustainable process that can be used to improve the electrochemical performance of lithium-ion batteries. Initial tests of high-voltage batteries modified in this way have been successful. This method could be used to make lithium-ion batteries, for example those for electric vehicles, significantly more efficient.

Lithium-ion batteries are considered a key technology for decarbonization. Therefore, researchers around the world are working to continuously improve their performance, for example by increasing their energy density. “One way to achieve this is to increase the operating voltage,” says Mario El Kazzi from the Center for Energy and Environmental Sciences at Paul Scherrer Institute PSI. "If the voltage increases, the energy density also increases.”

However, there is a problem: At operating voltages above 4.3 volts, strong chemical and electrochemical degradation processes take place at the transition between the cathode, the positive pole, and the electrolyte, the conductive medium. The surface of the cathode materials gets severely damaged by the release of oxygen, dissolution of transition metals, and structural reconstruction – which in turn results in a continuous increase in cell resistance and a decrease in capacity. This is why commercial battery cells, such as those used in electric cars, have so far only run at a maximum of 4.3 volts.

Deep parts of Great Barrier Reef ‘insulated’ from global warming – for now

Mesophotic corals on the Great Barrier Reef.
Photo Credit Prof Peter Mumby

Some deeper areas of the Great Barrier Reef are insulated from harmful heatwaves – but that protection will be lost if global warming continues, according to new research.

High surface temperatures have caused mass “bleaching” of the Great Barrier Reef in five of the last eight years, with the latest happening now.

Climate change projections for coral reefs are usually based on sea surface temperatures, but this overlooks the fact that deeper water does not necessarily experience the same warming as that at the surface.

The new study – led by the universities of Exeter and Queensland – examined how changing temperatures will affect mesophotic corals (depth 30-50 meters).

It found that separation between warm buoyant surface water and cooler deeper water can insulate reefs from surface heatwaves, but this protection will be lost if global warming exceeds 3°C above pre-industrial levels.

The researchers say similar patterns could occur on other reefs worldwide, but local conditions affecting how the water moves and mixes will mean the degree to which deeper water coral refuges exist and remain insulated from surface heatwaves will vary.

“Coral reefs are the canary in the coalmine, warning us of the many species and ecosystems affected by climate change,” said Dr Jennifer McWhorter, who led the research during a QUEX PhD studentship at the universities of Exeter and Queensland.

First-of-its-kind integrated dataset enables genes-to-ecosystems research

DOE national laboratory scientists led by Oak Ridge National Laboratory have developed the first tree dataset of its kind, bridging molecular information about the poplar tree microbiome to ecosystem-level processes.
Illustration Credit: Andy Sproles/ORNL, U.S. Dept. of Energy

The first-ever dataset bridging molecular information about the poplar tree microbiome to ecosystem-level processes has been released by a team of Department of Energy scientists led by Oak Ridge National Laboratory. The project aims to inform research regarding how natural systems function, their vulnerability to a changing climate, and ultimately how plants might be engineered for better performance as sources of bioenergy and natural carbon storage.

The data, described in Nature Publishing Group’s Scientific Data, provides in-depth information on 27 genetically distinct variants, or genotypes, of Populus trichocarpa, a poplar tree of interest as a bioenergy crop. The genotypes are among those that the ORNL-led Center for Bioenergy Innovation previously included in a genome-wide association study linking genetic variations to the trees’ physical traits. ORNL researchers collected leaf, soil and root samples from poplar fields in two regions of Oregon — one in a wetter area subject to flooding and the other drier and susceptible to drought. 

Details in the newly integrated dataset range from the trees’ genetic makeup and gene expression to the chemistry of the soil environment, analysis of the microbes that live on and around the trees and compounds the plants and microbes produce.

The dataset “is unprecedented in its size and scope,” said ORNL Corporate Fellow Mitchel Doktycz, section head for Bioimaging and Analytics and project co-lead. “It is of value in answering many different scientific questions.” By mining the data with machine learning and statistical approaches, scientists can better understand how the genetic makeup, physical traits and chemical diversity of Populus relate to processes such as cycling of soil nitrogen and carbon, he said.