It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Wednesday, September 03, 2025
Global methane levels continue rising as planet heats up
The world’s methane emissions continue to rise steadily with no signs of slowing, as global trade contributes some 30% to the total amount of the greenhouse gas swirling around the planet, a new study reveals.
As major trade patterns shift, South-South transactions now dominate global supply chains with developing countries increasingly participating in global supply chains. Asia and the developing Pacific region emerge as the largest contributors to global methane emissions, driven by rapid industrialisation and population growth.
Publishing their research today (3 Sep) in Nature Communications, an international team led by researchers at the Universities of Birmingham and Groningen provides the most comprehensive analysis to date of methane emissions across 164 countries and 120 sectors from 1990 to 2023.
With a global warming potential 80 times greater than CO₂ over a 20-year period, methane mitigation offers a critical opportunity to slow climate change in the near term. The researchers discovered that only developed countries have consistently reduced emissions while maintaining economic growth - mainly through improved production efficiency.
Lead author Prof. Yuli Shan, from the University of Birmingham, commented: “Methane has a short atmospheric lifespan, which means reductions today can have an immediate impact. Our findings underscore the need for coordinated global action, especially in developing regions where emissions are rising fastest.”
The study highlights fertiliser production as a key sector for action – also calling for targeted sectoral strategies, including advanced leak detection in oil and gas extraction, improved livestock feed formulations, and enhanced waste management practices. It also advocates for smarter consumption choices, such as reducing red meat intake, which has been linked to high methane emissions.
Co-corresponding author Professor Klaus Hubacek, from the University of Groningen, commented: “This study provides a roadmap for policymakers to integrate methane into national climate strategies. It’s not just about where emissions occur, but why—and that requires looking at the entire supply chain.”
Using the latest global trade and environmental accounts dataset, the researchers found that global trade is responsible for approximately 30% of methane emissions. Shifting trade patterns have led to increased emissions in developing countries, which often lack the technological efficiency of their developed counterparts.
While economic growth and changing consumption patterns have fuelled increases, improvements in energy efficiency and cleaner production technologies have helped offset some of the growth. Between 1998 and 2023, global average methane emission coefficients dropped by nearly 67%, reflecting significant technological progress.
Methane has contributed about 30% to global warming since pre-industrial times. Unlike CO₂, methane has a shorter atmospheric lifespan, making its reduction a fast-acting climate solution. It also contributes to air pollution, causing around one million premature deaths annually.
ENDS
Notes to editor:
The University of Birmingham is ranked amongst the world’s top 100 institutions. Its work brings people from across the world to Birmingham, including researchers, teachers and more than 8,000 international students from over 150 countries.
‘Global methane footprints growth and drivers 1990-2023’ - Yuli Shan, Kailan Tian, Ruoqi Li, Yuru Guan, Jiamin Ou, Dabo Guan, and Klaus Hubacek is published in Nature Communications.
Participating institutions: University of Birmingham, UK; Chinese Academy of Sciences, Beijing; University of Cambridge, UK; University of Groningen, the Netherlands; Tsinghua University, China; and University College London, UK.
Journal
Nature Communications
Method of Research
Data/statistical analysis
Subject of Research
Not applicable
Article Title
Global methane footprints growth and drivers 1990-2023
Article Publication Date
3-Sep-2025
Premiere in New Zealand: HALO research aircraft takes a detailed look at clouds in the South Pacific and Southern Ocean
Focus on the clean atmosphere of the Antarctic region
Leibniz Institute for Tropospheric Research (TROPOS)
The German research aircraft HALO has been prepared for deployment in New Zealand at its home base at the German Aerospace Center (DLR) in Oberpfaffenhofen.
Oberpfaffenhofen/Leipzig. The German research aircraft HALO is currently being prepared for deployment in New Zealand at its home base at the German Aerospace Center (DLR) in Oberpfaffenhofen: During the "HALO-South" mission, which will begin in September, researchers led by the Leibniz Institute of Tropospheric Research (TROPOS) will investigate the interaction of clouds, aerosols, and radiation over the Southern Ocean. To this end, HALO will spend five weeks conducting measurement flights over the oceans of the clean southern hemisphere from Christchurch, New Zealand. Since it went into service in 2012, HALO has only been used this far south once before. The mission in New Zealand is therefore a first: never before has a German research aircraft investigated the South Pacific and the adjacent Southern Ocean in this region. The aircraft measurements during ‘HALO-South’ are mainly funded by the German Research Foundation (DFG) with contributions from the Max Planck Institute for Chemistry (MPIC) and the German Aerospace Centre (DLR). They mark the start of intensive research cooperation between Germany and New Zealand.
The researchers hope that the measurements will not only provide important data for optimizing weather forecasts and climate models in the little-explored southern hemisphere, but also provide a better fundamental understanding of how the atmosphere and clouds will respond to a decline in anthropogenic emissions in the coming decades. For the team, looking into the cleaner atmosphere around Antarctica is therefore also a glimpse into the future.
The Southern Ocean around Antarctica is one of the cloudiest regions on Earth. Current climate models are based primarily on measurements in the northern hemisphere. Since the southern hemisphere has less land mass, fewer people, and less industry, it is significantly cleaner than the northern hemisphere. Because the atmosphere in the south is cleaner, there are fewer particles on which droplets or ice crystals can form. That is why there is less ice and more liquid water droplets in the clouds there than in the north. However, atmospheric models have so far been mainly aligned to data from the northern hemisphere, which leads to uncertainties in the representation of clouds in the southern hemisphere. This discrepancy has been known for several years, but there is a lack of measurements in the south to adjust the climate models accordingly.
"We hope that the large-scale HALO-South measurement campaign will enable us to make an important contribution to closing this gap," explains campaign leader Prof. Mira Pöhlker from TROPOS and the University of Leipzig. Twenty-two special measuring instruments from eight institutes will be used to study the entire cycle of cloud formation, from particle formation from precursor gases to cloud seeds and the radiation properties of clouds. "We are very pleased to have so many experienced experts on board to work together to answer questions such as: What aerosols are present in the Southern Ocean? Where do they come from? How do they change clouds?" A total of 176 flight hours are planned for the HALO-South mission. Around 50 researchers will be on site from the Leibniz Institute for Tropospheric Research (TROPOS), the Leipzig Institute for Meteorology at the Leipzig University, Johannes Gutenberg University Mainz (JGU), Goethe University Frankfurt (GUF), the Max Planck Institute for Chemistry (MPIC) in Mainz, the Karlsruhe Institute of Technology (KIT), the Institute of Atmospheric Physics of the German Aerospace Center (DLR), and the Forschungszentrum Jülich (FZJ). The aircraft is operated by the Flight Experiments (FX) facility at DLR Oberpfaffenhofen. The University of Canterbury, Christchurch, and MetService New Zealand are also participating with ground-based measurements.
September marks the end of winter in New Zealand and the beginning of spring in the Southern Ocean. This time of year was chosen to study the particularly clean atmosphere over the seas around New Zealand. The campaign will be embedded in parallel intensive field activities such as ground-based measurements from New Zealand and will be supported by satellite investigations. For example, the flight plan on site will be adjusted to the overflights of the ESA EarthCARE Earth observation satellite in order to fly exactly under the satellite orbit. The HALO-South mission will thus support the validation of the ESA satellite as well as the EU CleanCloud project, which investigates interactions between aerosols and clouds to improve our understanding of climate dynamics in a constantly changing world. Prof. Andreas Macke, Director of TROPOS, who initiated HALO-South in 2018, adds: "I am delighted that, with this and other projects in collaboration with international partners, will enable us to take research in the southern hemisphere to an unprecedented level."
The aircraft measurements taken by HALO will also be supplemented by ground measurements at the MetService New Zealand site in Invercargill in the far south of New Zealand. From September 2025 to March 2027, several remote sensing and in-situ measuring devices from TROPOS will analyze cloud properties during the "goSouth-2" measurement campaign to create a detailed contrast study between clean Antarctic air and aerosol-polluted Australian air. During HALO-South, in addition to the measurements in Invercargill, which are scheduled to last around two years, accompanying ground measurements will also be carried out by the Universities of Leipzig and Canterbury at the Tāwhaki National Aerospace Centre on the eastern side of New Zealand's South Island. There, a cloud radar and a Doppler wind lidar will contribute to recording the cloud structure that is important for the HALO-South campaign. The HALO-South mission thus marks the start of a series of intensive collaborations in the field of atmospheric research between Germany and New Zealand. The investigations around Antarctica are to be continued in 2027-2030 as part of the large-scale international research project "Antarctica InSync" with a series of Antarctic expeditions, which are currently being planned and will also play a role in atmospheric research.
HALO-South will provide urgently needed insights into the relationship between aerosols and clouds in the southern hemisphere, from the formation of cloud droplets and ice to changes in the radiation budget caused by clouds, which in turn are relevant for the formation of aerosols. These findings will be extrapolated to a larger scale using satellite data and global climate models. The campaign will build on and continue previous HALO campaigns that focused either on cloud and aerosol properties or on gas and aerosol properties (ML-CIRRUS, CIRRUS-HL, ACRIDICON, CAFE-EU, CAFE-Brasil, CAFE-Pacific, EMeRGe-EU, and EMeRGe-Asia). The measurements at HALO-South are intended to cover the interaction with aerosols throughout the entire life cycle of clouds, from formation to dissipation. With this extensive measurement campaign, the researchers aim to better understand the differences between the southern and northern hemispheres in order to improve weather forecasting and climate models. They also hope to gain a better understanding of how the atmosphere of the northern hemisphere will change in an increasingly decarbonized world without fossil-fuel based emissions.
The German research aircraft HALO has been prepared for deployment in New Zealand at its home base at the German Aerospace Center (DLR) in Oberpfaffenhofen.
The German research aircraft HALO has been prepared for deployment in New Zealand at its home base at the German Aerospace Center (DLR) in Oberpfaffenhofen.
The German research aircraft HALO has been prepared for deployment in New Zealand at its home base at the German Aerospace Center (DLR) in Oberpfaffenhofen.
The German research aircraft HALO has been prepared for deployment in New Zealand at its home base at the German Aerospace Center (DLR) in Oberpfaffenhofen.
Credit
Tilo Arnhold, TROPOS
HALO
The HALO research aircraft is a joint initiative of German environmental and climate research institutions. HALO was funded by the Federal Ministry of Research, Technology and Space (BMFTR), the Helmholtz Association, the Max Planck Society (MPG), the Free State of Bavaria, the Jülich Research Center (FZJ), the Karlsruhe Institute of Technology (KIT), and the German Aerospace Center (DLR).
HALO is operated by the German Research Foundation (DFG), the German Aerospace Center (DLR), the Max Planck Society (MPG), the Forschungszentrum Jülich (FZJ), the Karlsruhe Institute of Technology (KIT), and the Leibniz Institute for Tropospheric Research in Leipzig (TROPOS). The DLR is both the owner and operator of the aircraft.
Method of Research
Observational study
Researchers describe for the first time brain signals associated with forgetting unpleasant memories in humans
The discovery may help improve therapies for post-traumatic stress disorder and anxiety
Suppression of fear-related memories after unpleasant experiences is very critical for adaptive behaviour, as it allows one to inhibit responses that could lead to psychiatric problems such as anxiety or depression. Recent theories propose that the extinction of these memories takes place when new, highly context-dependent memories that suppress the initial fear response are created. Electrophysiological experiments on mice support this theory, and show a relationship between certain oscillations of signals recorded in the brain regions of the amygdala and hippocampus with the learning and extinction of fear-response memories. However, this relationship has so far not been confirmed in the human brain.
In an article published recently in Nature Human Behaviour, researchers at the Universitat Autònoma de Barcelona and Ruhr-Universität Bochum, Germany, describe for the first time the electrophysiological signals associated with the extinction of aversive memories in humans.
Researchers employed a powerful technique to study the characteristics of human memory called Representational Similarity Analysis (RSA), which provides information on how brain regions represent information. “The technique allows us to achieve a more detailed and mechanistic understanding of episodic memories, overcoming traditional approaches based solely on brain activation”, explains Daniel Pacheco-Estefan, first author of the paper and researcher at the UAB Department of Basic, Developmental and Educational Psychology.
The study provides a detailed characterisation of the neural representations involved in the formation and extinction of associative memories. Researchers used a novel experimental design that included multiple cues and contexts in each phase of the experiment (memory acquisition, memory extinction and testing). This allowed them to study the representations underlying classical conditioning in humans and to validate, for the first time, hypotheses derived from studies in animal models. The study involved the participation of 49 epileptic patients who had already had electrodes implanted - for the treatment of the disease - in the brain area related to fear memories and the extinction of these memories. The patients were shown a series of neutral images (a hair dryer, a fan and a toaster), associating some of them with an unpleasant stimulus (a sound), while the brain activity was recorded. Later, the procedure was repeated, but this time without associating the images with the aversive stimulus, in order to promote the extinction of aversive memories.
Among the main findings, researchers observed an increase in theta activity - a type of oscillatory signal emitted by the brain's electrical activity - in the amygdala - a key structure in the coding of emotional states - when previously unpleasant stimuli were presented during extinction learning, suggesting a safety signal. In addition, they observed higher representational similarity between items that were punished during extinction, i.e., those that had been associated with negative sounds. “This result is consistent with previous research that has identified a generalised representational signature for unpleasant memories, which favours their involuntary reappearance in all kinds of situations in subjects who have undergone traumatic experiences”, emphasises Daniel Pacheco-Estefan.
The study also shows that extinction memories are highly dependent on the context in which they are formed. Retrieval of fear memory is more likely than that of safety memory during the test phase, when representations of extinction contexts are more pronounced and specific during extinction. For Pacheco-Estefan “this finding has relevant implications for understanding why fear memories that have already been extinguished, return once patients are out of the therapeutic context”. Nikolai Axmacher, coordinating researcher at RUB, adds: “It seems that extinction memories are stored like memories of unique episodes – for the patient, the safe situation may be regarded as an exception that is unlikely to repeat.”
Overall, these pioneering results open new paths to investigating the fundamental mechanisms of episodic and autobiographical memory in humans, and “could inspire the development of more effective therapeutic interventions in patients with post-traumatic stress or anxiety disorders”, concludes the UAB researcher.
How physicians feel about artificial intelligence in medicine has been studied many times. But what do patients think? A team led by researchers at the Technical University of Munich (TUM) has investigated this for the first time in a large study spanning six continents. The central finding: the worse people rate their own health, the more likely they are to reject the use of AI. The study is intended to help align future medical AI applications more closely with patients’ needs.
Acceptance by patients is essential for the effective use of artificial intelligence in medicine, regardless of whether AI is used as a diagnostic tool, to create individual treatment plans or for other applications. The international research network of the COMFORT study therefore surveyed around 14,000 patients in 74 clinics in 43 countries. In order to cover a wide range of diseases, the survey was conducted in radiology departments that carry out X-ray, CT and MRI examinations on behalf of other specialist disciplines.
A majority – 57.6% – viewed the use of AI in medicine positively. However, some differences emerged within the cohort: men were slightly more favorable at 59.1% than women at 55.6%. Approval also rose markedly with greater familiarity with technology and higher self-rated understanding of AI. Among respondents who described themselves as highly knowledgeable about AI, 83.3% were positive about using it in medicine.
Negative view of AI in severe illness
The more severe a person’s own illness, the more negative their attitude toward AI. More than half of patients in very poor health rated medical AI “extremely negative” or “rather negative” (26.6% and 29.2%, respectively). Among those in very good health, the corresponding figures were 1.3% and 5.3%.
“The exact reasons for negative attitudes among seriously ill patients cannot be determined from our study,” says Dr. Felix Busch, assistant physician at TUM’s Institute of Diagnostic and Interventional Radiology and the study’s first author. “We suspect that experiences with the health care system, illness burden, and psychological factors play a role.”
Explainability of medical AI is crucial
Respondents expressed clear preferences for how AI should be used and designed. For 70.2%, it was important that medical AI be ‘explainable,’ allowing users to see the steps leading to its conclusions. In addition, 72.9% wanted these technologies to function as tools, with physicians making the final decisions.
Only 4.4% favored diagnoses made exclusively by AI. At the same time, just 6.6% wanted diagnoses to be made entirely without AI. These questions referred to hypothetical scenarios in which human clinicians and AI were equally accurate. “The results show that explainability must be considered from the outset,” says Felix Busch.
Basis for further studies
One methodological limitation is the survey timing in 2023. “Since then, large language models in particular have advanced considerably. Patient attitudes may have changed,” says Adjunct Teaching Professor Dr. Keno Bressem, senior lecturer and, together with Adjunct Teaching Professor Dr. Lisa Adams, senior author of the study. “Follow-up surveys are needed to test this and to align the development of medical AI with patients’ needs,” adds Dr. Lisa Adams. A follow-up study by the COMFORT consortium using the same questionnaire is already underway.
Publication:
Busch F, Hoffmann L, Xu L, et al. Multinational Attitudes Toward AI in Health Care and Diagnostics Among Hospital Patients. JAMA Netw Open. 2025;8(6):e2514452. doi: 10.1001/jamanetworkopen.2025.14452
Multinational Attitudes Toward AI in Health Care and Diagnostics Among Hospital Patients
Article Publication Date
10-Jun-2025
COI Statement
Dr Rodriguez-Granillo reported being a consultant for Caristo Diagnostics outside the submitted work. Dr Kitamura reported receiving personal fees from Bunkerhill Health, MD.ai, Sharing Progress in Cancer Care, and GE Healthcare outside the submitted work; being an early career consultant to the editor of Radiology, an associate editor of Radiology: Artificial Intelligence, vice-chair of the Society for Imaging Informatics in Medicine machine learning committee, member of the Radiological Society of North America (RSNA) AI committee, and member of the RSNA Radiology Informatics Council. Dr Bressem reported receiving grants from Bayern Innovativ, the funding agency of the State of Bavaria, Germany; German Federal Ministry of Education and Research; and the Wilhelm-Sander Foundation; receiving a scholarship from the Max Kade Foundation; and receiving personal fees from Canon Medical Systems Corporation and GE HealthCare; all outside the submitted work. Dr Bwambale reported receiving personal fees as compensation for expenses incurred during the study outside the submitted work. Dr Esteban-Villarrubia reported receiving grants from Astellas and receiving personal fees from BMS, Ipsen, MSD, and Janssen outside the submitted work. Dr Ferraioli reported receiving personal fees from Canon Medical Systems, Philips Healthcare, Mindray Bio-Medical Electronics, Siemens Healthineers, Esaote SpA, and Elsevier outside the submitted work. Dr Kader reported receiving personal fees from Odin Vision Ltd outside the submitted work. Dr Miyake reported receiving grants from Novartis Pharma, Rhoto Pharma, Kaneka, and Daiichi Sankyo Pharma; and receiving personal fees from Santen Pharma, FINDEX Inc, Chugai Pharma, JINS, and Senju Pharma outside the submitted work. Dr Niehues reported receiving personal fees from Canon Medical, Bracco Imaging, and Teleflex during the conduct of the study. Dr Sado reported receiving personal fees from Fitting Cloud Inc outside the submitted work. Dr Truhn reported being a shareholder of StratifAI GmbH and Synagen GmbH.
An eye for the sky
Bees use the sun's position in the sky for navigation – even on cloudy days
The hunt for nectar can take honeybees kilometres away from their hive into unknown territory – and yet, they always find their way back. The sun's position in the sky serves as a kind of compass for bees, even when clouds or other objects block it from view. They owe this ability to the special structure of their complex eyes, which they use to analyze patterns of polarized light in the sky that are invisible to humans.
A research team from the University of Konstanz and the University of Ljubljana has shed light on the visual properties of this specialized part. In their recent study published in Biology Letters of the Royal Society Publishing, the team examines how some light detector cells in bees' eyes are connected to each other. They discovered that in the skyward-facing area of the bee's eye, a signal received by one cell also appeared in others. This unexpected connection produces a less-detailed but more accurate image of polarized light in the sky.
One facet among many Unlike the human eye, in which a single lens focuses the light from the environment onto our visual cells, bees' eyes are comprised of thousands of individual facets (ommatidia), each one with its own lens. These are known as complex eyes. In the case of bees, the complex eyes contain different specialized areas. "Most of the facets provide a sharp image of the surroundings. However, the upper region of the eyes contains a group of ommatidia that operate differently and are responsible for detecting polarized light in the sky. We took a closer look at this area”, explains Georgios Kolyfetis, co-author of the study. Kolyfetis is a doctoral researcher from James Foster's research team in the Department of Biology at the University of Konstanz
"Light-detecting cells in each of these upper facets are less sensitive than in the facets elsewhere. This keeps bees from getting blinded as they use this part of their eyes to look at the daytime sky", he adds. This is clearly useful, yet it comes at a cost: The reduced sensitivity of these facets prevents bees from detecting subtle changes in the sky. "While they see the rest of the world in more detail, bees see the sky more like a watercolour painting in which adjacent brush strokes blend into each other and details are hidden", explains James Foster, who led the study. "But this is exactly what makes this part of the eye particularly good at detecting large-scale polarization patterns in the sky."
Working together to get the full picture To understand this, it is worth taking a look at how the human eye works. Our eyes focus light onto individual pixels and use them to construct an overall picture. At night or in poor lighting, this precise sight is no longer possible. The human eye compensates by combining multiple pixels together. A loss of detail is the trade-off for amplifying the light signal. Scientists call this process "spatial summation". This study reveals that the upper group of facets in bee eyes work together in the same way – and around the clock, not just at night.
However, the function is not exactly the same. "In mammalian and human eyes, nerve cells combine the signals of multiple light receptors and send the joint signal on to the brain. In the case of bees, some of the light cells are directly connected to each other", explains neurobiologist Gregor Belušič from the University of Ljubljana. "Each individual facet thus also responds to what neighbouring facets see."
Seeing what's important What purpose does this serve? The blurry image of the space above them can help bees to tune out unimportant information and only focus on the big picture. "Bees register and analyze the polarization pattern of light in the sky. Based on this information, they determine the sun's position and align their inner compass accordingly. They simply blend out disruptions like clouds or branches overhead", Kolyfetis concludes.
Discovering this function in bee eyes is interesting not only from a biological perspective, but it could be used to further develop modern technologies. "Autonomous vehicles could also benefit from this strategy for navigation. Cameras pointed at the sky could serve as a kind of backup compass if GPS and magnetic signals are unreliable or fail", Foster says. Since bees are able to perform this feat with a small group of facets, "artificial bee eyes" could provide an inexpensive way to supplement other autonomous navigation systems.
Key facts:
Original publication: George E. Kolyfetis, Gregor Belušič, James J. Foster: „Electrophysiological recordings reveal photoreceptor coupling in the dorsal rim areas of honeybee and bumblebee eyes” (2025), Biol. Lett.21:20250234; DOI: 10.1098/rsbl.2025.0234
Georgios Kolyfetis is a doctoral researcher in the field of neurobiology at the University of Konstanz. His research focuses on bee sight.
Dr James Foster is a neurobiologist at the University of Konstanz. His research centres on how animals detect and respond to polarized light.
