New study finds higher hantavirus risk in drier, underdeveloped areas

A study of the long-term risk of contracting hantavirus across large geographic areas provides public health officials with information about populations most at risk for contracting hantavirus and the potential drivers of disease risk. Humans become infected with hantavirus when they inhale the airborne particles of feces and urine of disease-carrying rodents.
Photo Credit: Zoshua Colah

In a recent study of the contiguous United States, Los Alamos National Laboratory researchers found that the risk of disease from hantavirus is higher in drier, underdeveloped geographic areas with more socioeconomic vulnerability and increased numbers of unique rodent species. This is the first study to examine the combined effects of multiple variables — including socioeconomic, environmental, land use and rodent species — to determine which are most likely to predict the risk of people contracting hantavirus.

“We ran each of these variables separately — looking at where people are most at risk given just the environmental variables, just the land-use variables, etc. — and then we combined them all,” said Morgan Gorris, a scientist at Los Alamos and lead author on the study published in Transboundary and Emerging Diseases. “This gave us a map of where people are most at risk of being exposed to hantavirus and contracting hantavirus pulmonary syndrome (HPS).”

Carbon-rich waters are becoming even more acidic as atmospheric CO2 levels rise

Orange cup corals, pictured growing on rocks above, are native to the Pacific Ocean. As they grow, corals incorporate minerals from seawater, leaving a valuable historical record in their skeletons. In this University of Washington-led study, researchers compare preindustrial corals to modern specimens to show how quickly the ocean is acidifying.
Photo Credit: Alexander Vasenin
(CC BY-SA 4.0)

The waters bordering North America could soon be inhospitable to critical marine creatures if the Northeastern Pacific Ocean continues to acidify at the current rate, a new study shows.

Earth’s oceans have become approximately 30% more acidic since the industrial revolution began more than 200 years ago. Acidification changes marine chemistry and depletes key minerals that calcifying organisms, such as corals and clams, need to build their skeletons and shells. The Northeastern Pacific is naturally more acidic than other oceans, fueling debate about how much its chemistry will change in the coming decades.

The study, published in Nature Communications, shows that high baseline acidity makes the water more sensitive to additional carbon dioxide from human activities. Analyses of coral skeletons from the past century revealed that CO2 has been accumulating in North American waters faster than in the atmosphere, driving rapid acidification.

Fossil fuel CO2 emissions hit record high in 2025

Photo Credit: Chris LeBoutillier

Global carbon emissions from fossil fuels are projected to rise by 1.1% in 2025 – reaching a record high, according to new research by the Global Carbon Project. 

The 2025 Global Carbon Budget projects 38.1 billion tons of fossil carbon dioxide (CO2) emissions this year. 

Decarbonization of energy systems is progressing in many countries – but this is not enough to offset the growth in global energy demand. 

With projected emissions from land-use change (such as deforestation) down to 4.1 billion tons in 2025, total CO2 emissions are projected to be slightly lower than last year. 

With the end of the 2023-24 El Niño weather pattern – which causes heat and drought in many regions – the land “sink” (absorption of CO2 by natural ecosystems) recovered this year to the pre-El Niño level.

Higher methane emissions from warmer lakes and reservoirs may exacerbate worst-case climate scenario

Lakes are large sources of methane.
Photo Credit:Monica Westman

Emissions of the greenhouse gas methane from lakes and reservoirs risk doubling by the end of the century due to climate change according to a new study from Linköping University, Sweden, and NASA Ames Research Center in the US. This in turn could raise Earth’s temperature more than suggested by the UN climate panel IPCC’s current worst-case scenario. 

“This study makes it even clearer that we really, really want to change the climate scenario as quickly as possible. The future will be very uncertain if we don’t,” says Professor David Bastviken at Linköping University. 

Lakes and water reservoirs are some of the largest sources of methane on Earth. The methane emitted is largely formed as microorganisms decompose organic matter in oxygen-free environments. Before industrialization, natural methane emissions to the atmosphere were in balance with the methane breakdown processes. If the ongoing climate change disturbs the natural balance causing emissions to increase, global warming is at risk of worsening. 

Polar climate change could amplify global health risks, study warns

Photo Credit: Annie Spratt

Climate change in Earth’s polar regions is emerging as an under-recognised driver of global health risks, with consequences reaching far beyond the Arctic and Antarctic, researchers argue.

A study by an international team of scientists led by Professor Gail Whiteman from the University of Exeter Business School presents a comprehensive framework mapping the complex connections between physical changes in the Arctic and Antarctic which could amplify climate impacts to human health worldwide.

The researchers reviewed a wide range of scientific literature across climate science, public health and other fields. They found that current models underestimate the direct and indirect impacts of changing polar regions on global health issues – from chronic disease to mental health challenges, and pregnancy complications.

Sand mining reducing the flow of Southeast Asia’s largest lake, new report warns

The Tonle Sap Lake (TSL) in Cambodia is one of the most ecologically diverse lake ecosystems globally
Photo Credit: Marco De Gregorio

A new study led by Loughborough University has highlighted how sand mining is endangering the normal functioning of the largest freshwater lake in Southeast Asia.

The Tonle Sap Lake (TSL) in Cambodia is one of the most ecologically diverse lake ecosystems globally, and is the fourth most productive in terms of fish productivity.  

Since 1997 the TSL has been recognized as a UNESCO World Heritage Biosphere Reserve, serving as a habitat for globally significant populations of endangered amphibians, reptiles, mammals, and birds, spanning a diverse array of over 800 species. 

Deep-sea mining waste threatens life and food webs in ocean’s dim “twilight zone”

Illustration showing midwater impacts of deep sea mining operations. Image credit: Dowd et al 2025 (Nature Communications)
Illustration Credit: Amanda Merritt

A new study led by researchers at the University of Hawai‘i (UH) at Mānoa is the first of its kind to show that waste discharged from deep-sea mining operations in the Pacific’s biodiverse Clarion-Clipperton Zone (CCZ) could disrupt marine life in the midwater “twilight zone” — a vital region 200-1,500 meters below sea level that supports vast communities of zooplankton, tiny animals that serve as the ocean’s basic food building blocks. Specifically, it finds that 53% of all zooplankton and 60% of micronekton, which feed on zooplankton, would be impacted by the discharge, which could ultimately impact predators higher up on the food web.  

“When the waste released by mining activity enters the ocean, it creates water as murky as the mud-filled Mississippi River. The pervasive particles dilute the nutritious, natural food particles usually consumed by tiny, drifting Zooplankton,” said Michael Dowd, lead author of the study and Oceanography graduate student in the UH Mānoa School of Ocean and Earth Science and Technology (SOEST). “Micronekton, small shrimp, fish and other animals that swim, feed on zooplankton. Some migrate between the depths and near surface waters and they are consumed by fish, seabirds and marine mammals. Zooplankton’s exposure to junk food sediment has the potential  to disrupt  the entire food web.” 

Dry grass: Research project explores the effect of multi-year drought on grasslands

As a dry spell stretches from months to years, grasslands can adapt — to a point.
Photo Credit: Scientific Frontline / Heidi-Ann Fourkiller

A recent paper in the journal Science, “Drought intensity and duration interact to magnify losses in primary productivity,” explores how moderate and extreme droughts affect grasslands around the world. The paper has more than 180 international co-authors, with Binghamton University Assistant Professor of Ecosystem Science Amber Churchill among them.

Known as a distributed network, research projects of this type call upon collaborators to perform the same experiments locally, Churchill explained.

“The idea is that everyone uses the same methodology, but each local site is independently responsible for the maintenance of their site, data collection and ongoing measurements,” she said. “Often, individual sites will collect data in addition to the core project’s data.”

The experiment measured productivity, or how much plant biomass grows in a year. Less rain typically means less productivity, but the long-term picture is complicated by a number of factors. For one, not all grasslands are created equal; they come in a variety of types, with varying precipitation levels. Removing 10% of rainfall in an arid grassland is the equivalent of removing 40% of the precipitation in a wetter ecosystem, according to the research.

Plant protection products change the behavior of non-target organisms

The honeybee (Apis mellifera) served as the model organism for pollinating insects.   
Photo Credit: André Künzelmann / UFZ

Plant protection products protect crops from pests, diseases and weeds. However, many of the fungicides, herbicides and insecticides also have a negative effect on terrestrial and aquatic organisms such as pollinators or fish that are not the primary target of their use. How their behavior changes after exposure to plant protection products is now the focus of a cross-habitat study by scientists from the Helmholtz Centre for Environmental Research (UFZ). The behavioral changes found in the animal models were significant and are an indication of the effect of plant protection products on non-target organisms in the wild. The work indicates that more complex and relevant behavioural tests should be included in the risk assessment of plant protection products in the future. The study was published in the journal Environment International.

The application of plant protection products in agriculture is subject to strict regulations. Nevertheless, organisms that are not the primary target of their use, so-called non-target organisms, inevitably come into contact with these substances and can potentially be harmed by them. "Wild bees and other pollinators can come into contact with quite high concentrations shortly after spraying. But animals in aquatic habitats are also at risk," says UFZ biologist Prof. Martin von Bergen, one of the two joint principal investigators. "Rainfall gradually washes plant protection products into the surrounding waters. They don't simply remain and only affect the area where they are applied."

New modeling shows difficult future for the GBR under climate change

Coral bleached by high water temperatures in the Pacific Ocean.
Photo Credit: Professor Peter Mumby

The most sophisticated modeling to date forecasts that under the current global emissions pathway the Great Barrier Reef could lose most of its coral by the end of the century, but curbing climate change and strategic management will help coral resilience.

A research team led by The University of Queensland simulated different future climate scenarios driven by a range of plausible global emissions trajectories.

Dr Yves-Marie Bozec from UQ’s School of the Environment said the comprehensive modelling of individual corals included their ability to adapt to warmer water, large-scale reef dynamics and their interconnections on ocean currents.

“We ran all of those factors with the most up to date climate projections – and the news was not good,” Dr Bozec said.

“We forecast a rapid coral decline before the middle of this century regardless of the emissions scenario.

“Corals may partially recover after 2050, but only if ocean warming is sufficiently slow to allow natural adaptation to keep pace with temperature changes.

“Adaptation may keep pace if global warming does not exceed 2 degrees by 2100.

“For that to happen, more action is needed globally to reduce carbon emissions which are driving climate change.”

Long-lived contrails usually form in natural ice clouds

Contrails over Jülich, embedded in very thin and therefore barely visible cirrus clouds.
Photo Credit:© Andreas Petzold

Long-lived contrails form predominantly not in cloud-free skies, but within already existing ice clouds. This is the conclusion reached by a team of scientists from Forschungszentrum Jülich, the University of Cologne, the University of Wuppertal, and Johannes Gutenberg University Mainz. Using extensive observational data, the researchers were able, for the first time, to systematically determine the atmospheric conditions under which long-lasting contrails form – whether in cloudless skies, in very thin and barely visible ice clouds, or in more clearly visible ice clouds, known as cirrus clouds. The result: more than 80 percent of all persistent contrails form within pre-existing clouds, mostly within natural cirrus clouds. The effects of this on the climate are not yet clearly understood. The study, now published in Nature Communications, provides important insights for further research – and, beyond that, strong arguments for taking cloud cover into account when planning flight routes adapted to climate considerations.

Study paints detailed picture of forest canopy damage caused by ‘heat dome’

Heat dome foliar scorch
Photo Credit: Courtesy of Oregon State University

A satellite imagery analysis shows that the 2021 “heat dome” scorched almost 5% of the forested area in western Oregon and western Washington, turning foliage in canopies from a healthy green to red or orange, sometimes within a matter of hours.

Damage to foliage leads to a range of problems for trees including reduced photosynthesis and increased vulnerability to pests and disease, scientists at Oregon State University say.

The study by researchers at OSU and the U.S. Forest Service identified 293,546 hectares of damaged forest, a total area of more than 1,000 square miles that’s nearly the size of Rhode Island. They took a deep dive into the affected areas to learn the factors that made some stands more vulnerable than others to the extreme heat event experienced by the Pacific Northwest in June 2021.

Unexpectedly high emissions from wastewater treatment plants

With a custom built drone, researchers at LiU have shown that greenhouse gas emissions from many wastewater treatment plants may be more than twice as large as previously thought.
Photo Credit: Magnus Gålfalk

Greenhouse gas emissions from many wastewater treatment plants may be more than twice as large as previously thought. This is shown in a new study from Linköping University, where the researchers used drones with specially manufactured sensors to measure methane and nitrous oxide emissions.

“We show that certain greenhouse gas emissions from wastewater treatment plants have been unknown. Now that we know more about these emissions, we also know more about how they can be reduced,” says Magnus Gålfalk, docent at Tema M – Environmental Change at Linköping University, who led the study published in the journal Environmental Science & Technology.

Wastewater treatment plants receiving sewage from households and industries account for approximately 5 per cent of human-induced methane and nitrous oxide emissions, according to the UN Intergovernmental Panel on Climate Change, IPCC.

To calculate this, the IPCC uses so-called emission factors that are linked to how many households are connected to the treatment plant. The calculation model then yields a number for the emissions from each wastewater treatment plant. This number is an estimate and not the result of actual measurements, which has turned out to be problematic.

Climate report: Earth on dangerous path but rapid action can avert the worst outcomes

Palisades Fire. Photo taken Jan. 8, 2025.
Photo Credit: Cal Fire.

2024 was the hottest year on record and likely the hottest in at least 125,000 years, according to an annual report issued by an international coalition led by Oregon State University scientists.

“Without effective strategies, we will rapidly encounter escalating risks that threaten to overwhelm systems of peace, governance, and public and ecosystem health,” said co-lead author William Ripple. “In short, we’ll be on the fast track to climate-driven chaos, a dangerous trajectory for humanity.”

Despite the sixth annual report’s ominous findings – 22 of the planet’s 34 vital signs are at record levels – Ripple stresses that “it’s not too late to limit the damage even if we miss the temperature mitigation goal set by the 2015 Paris Agreement,” an international treaty that set targets for reducing greenhouse gas emissions.

But with many vital signs, including greenhouse gas concentrations in the atmosphere, ocean acidity and ice mass, continuing to trend sharply in the wrong direction, the authors note that time is definitely of the essence.

Polar bears act as crucial providers for Arctic species

Photo Credit: Credit: San Diego Zoo Wildlife Alliance

A new study published in the scientific journal Oikos reveals for the first time the critical role polar bears play as carrion providers for Arctic species. Researchers from University of Manitoba and San Diego Zoo Wildlife Alliance, alongside researchers from Environment and Climate Change Canada, and the University of Alberta, have estimated that polar bears leave behind approximately 7.6 million kilograms of their prey annually, creating a massive and vital food source for a wide network of arctic scavenger species.

This research demonstrates that these apex predators are a crucial link between the marine and terrestrial ecosystems. By hunting seals on the sea ice and abandoning the remains, polar bears transfer a substantial amount of energy from the ocean to the ice surface, making it accessible to other animals. The study identifies at least 11 vertebrate species known to benefit from this carrion, including Arctic foxes and ravens, with an additional eight potential scavenger species.

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.

Trillions of insects fly above us - weather radar reveals alarming declines

The marmalade hoverfly is a well known migrant that comes across the Channel each year.
Photo Credit: Christopher Hassall

Scientists have made a breakthrough in monitoring insect populations across the UK using an unexpected tool: weather radar.

Traditionally used to track rainfall and storms, these radars are now helping researchers monitor the daily movements and long-term numbers of flying and floating creatures - including bees, moths, flies, spiders, and other arthropods.

The study, published in the peer-reviewed journal Global Change Biology, examined radar data collected between 2014 and 2021 over 35,000 square kilometers of the UK. It found that while daytime insect numbers have remained relatively stable or even increased in southern regions, nighttime-airborne insects have declined overall - especially in the far north.

Retreating Glaciers May Send Fewer Nutrients to the Ocean

Northwestern Glacier in Alaska has retreated approximately 15 kilometers (nine miles) since 1950.
Photo Credit: Kiefer Forsch/Scripps Institution of Oceanography.

The cloudy, sediment-laden meltwater from glaciers is a key source of nutrients for ocean life, but a new study suggests that as climate change causes many glaciers to shrink and retreat their meltwater may become less nutritious. 

Led by scientists at UC San Diego’s Scripps Institution of Oceanography, the study finds that meltwater from a rapidly retreating Alaskan glacier contained significantly lower concentrations of the types of iron and manganese that can be readily taken up by marine organisms compared to a nearby stable glacier. These metals are scarce in many parts of the ocean including the highly productive Gulf of Alaska, and they are also essential micronutrients for phytoplankton, the microorganisms that form the base of most marine food webs.

Dusty air is rewriting your lung microbiome

UCR researcher collecting dust from the Salton Sea.
Photo Credit: Linton Freund/UCR

Dust from California’s drying Salton Sea doesn’t just smell bad. Scientists from UC Riverside found that breathing the dust can quickly re-shape the microscopic world inside the lungs. 

Genetic or bacterial diseases have previously been shown to have an effect on lung microbes. However, this discovery marks the first time scientists have observed such changes from environmental exposure rather than a disease. 

Published in the journal mSphere, the study shows that inhalation of airborne dust collected close to the shallow, landlocked lake alters both the microbial landscape and immune responses in mice that were otherwise healthy.

“Even Salton Sea dust filtered to remove live bacteria or fungi is altering what microbes survive in the lungs,” said Mia Maltz, UCR mycologist and lead study author. “It is causing deep changes to our internal environment.”

Increasing Heat is Super-Charging Arctic Climate and Weather Extremes

Photo Credit: Master Unknown

By evaluating historical climate records, observational and projection data, an international team of researchers found a “pushing and triggering” mechanism that has driven the Arctic climate system to a new state, which will likely see consistently increased frequency and intensity of extreme events across all system components – the atmosphere, ocean and cryosphere – this century.

“We know that mean temperatures are rising, and the Arctic is commonly considered an indicator of global changes due to its higher sensitivity to any perturbation of external and internal forcings,” says Xiangdong Zhang, research professor at North Carolina State University and senior scientist at the North Carolina Institute for Climate Studies.

“The annual mean warming rate of the Arctic is more than three times the global average – this is known as Arctic amplification,” Zhang says. “But no systematic review has been done about the interplay of warmer temperatures with the dynamics of atmosphere, ocean and sea ice in weather and climate extremes around the Arctic.” Zhang is the lead author of the study.