Exclusive: Campaigners argue news channel’s attacks on climate action ‘work in financial interests’ of Sir Paul Marshall

The hedge fund run by the co-owner of GB News almost tripled its investments in fossil fuel companies in the first quarter of 2026 to $2.8bn (£2.1bn), the Guardian can reveal.

Critics have accused Sir Paul Marshall of “cashing in on climate chaos” and have claimed the news channel, which frequently attacks climate science and action, was “working in its owner’s financial interests”.

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© Photograph: Anna Gordon

© Photograph: Anna Gordon

© Photograph: Anna Gordon

The Ocean Discovery League compiled records of approximately 44,000 deep-sea dives for a study published in Science Advances conducted between 1958 and the early 2020s. The dives were carried out by crewed submersibles, remotely operated vehicles, and autonomous underwater vehicles equipped with cameras, across dozens of institutions, flagged to multiple countries. When the League used this dataset to calculate the total area of seafloor that has been directly observed by a camera-bearing vehicle, the result was less than 0.001 per cent of the ocean floor below 200 metres depth.

The area amounts to roughly 2,100 square kilometres. For comparison, the state of Rhode Island covers about 4,000 square kilometres. Six decades of deep-sea exploration, by some of the best-equipped oceanographic programmes in the world, have produced direct visual coverage of the seafloor equivalent to a single small state.

The deep ocean covers approximately 335 million square kilometres.

What direct observation means, and what it does not

The figure requires some care in interpretation, because the deep ocean is not unknown in a simple sense. Acoustic mapping, particularly multibeam sonar, has produced detailed topographic charts of significant portions of the seafloor. The Nippon Foundation-GEBCO Seabed 2030 project, an ongoing international effort, aims to map the entire ocean floor at resolutions suitable for identifying major geological features; current estimates place mapped coverage at roughly 27 per cent of the total area. By some measures, we have higher-resolution topographic data for the surfaces of Mars and the Moon than for Earth’s own ocean floor, though that comparison depends on the resolution threshold used and is contested by some oceanographers.

Sonar tells you the shape of the bottom. It does not tell you what lives there. It does not reveal the composition of the substrate at close range, the structure of biological communities on the seafloor, the chemical processes occurring at hydrothermal vents, or the condition and diversity of organisms across different sites. For that kind of knowledge, a vehicle has to get close enough to look.

The Ocean Discovery League dataset measures only this second type of knowledge: the area of seafloor that has been filmed or photographed from a vehicle operating near the bottom. By that definition, the proportion observed is less than 0.001 per cent. This is the specific gap the dataset establishes.

Where the dives went

The approximately 44,000 dives in the dataset are not evenly distributed across the ocean. The analysis shows strong concentrations in the waters around the United States, Japan, and New Zealand, which together with France and Germany account for 97 per cent of all recorded dives. Much of the southern hemisphere and the central Pacific, which together represent a substantial fraction of the global deep ocean, has rarely or never been visited by a camera-equipped vehicle.

Depth distribution is also uneven. A disproportionate share of dives targeted waters between 200 and 2,000 metres, the upper portion of the deep zone. The hadal environment, the ocean trenches below 6,000 metres, remains the least observed of all, despite representing some of the most geologically and biologically distinctive terrain on the planet.

This geographic and depth concentration reflects the practical constraints of deep-sea exploration: where research vessels operate, which institutions have submersibles capable of reaching target depths, and which regions have received sustained scientific interest. It is not a random sample of the ocean.

The comparison with space exploration

The disparity between ocean and space exploration funding has been raised many times, and the Ocean Discovery League’s dataset frames its findings partly against this contrast. NASA’s annual budget has run to roughly 20 to 25 billion US dollars in recent years. The budget dedicated to systematic deep-sea exploration globally is a fraction of that figure.

The comparison has real limits. Space exploration serves scientific, commercial, and strategic objectives that cannot be straightforwardly compared with ocean science. Satellite infrastructure, planetary science, and Earth observation systems generated through space programmes benefit oceanography directly: sea-surface temperature data, altimetry for measuring currents, and biological productivity mapping all depend on orbital assets. The budget comparison obscures these linkages.

The point the dataset makes is narrower: that direct visual survey of the deep ocean has been slow, geographically patchy, and concentrated in a small number of well-resourced institutions, and that after six decades the coverage remains at a fraction of a per cent. Whether that constitutes an appropriate allocation of scientific resources is a policy question the League’s data cannot answer. What the data can establish is the baseline: how much has actually been seen, and how much has not.

What to watch

The Ocean Discovery League has argued that the solution to limited coverage lies in distributed exploration: more, smaller, lower-cost vehicles deployed from a broader base of institutions, rather than a small number of large research vessels and deep-rated submersibles. The economics of remotely operated vehicles have shifted enough in the past decade that capable systems are now accessible to research universities and smaller oceanographic institutions that could not previously have operated them.

Whether distributed deployment produces systematic coverage at meaningful scale is an open question. Approximately 44,000 dives across sixty years represent an enormous cumulative effort; the remaining area is not a minor gap. The dataset’s value, as the League frames it, is establishing a rigorous baseline rather than offering an easy remedy. Before this analysis, the scale of the gap was estimated. Now it is measured.

The post Scientists have directly observed less than 0.001 percent of the deep ocean floor — an area comparable to the state of Rhode Island — despite decades of exploration, according to a global dataset of 44,000 deep-sea dives compiled by the Ocean Discovery League appeared first on Space Daily.

On the evening of 5 April 1815, the residents of Java and surrounding Indonesian islands heard what they believed were cannon shots in the distance. British colonial administrators dispatched troops to investigate, assuming a naval engagement was underway somewhere offshore. The sounds were heard as far away as Sumatra, more than 2,000 kilometres from their source, and continued intermittently for five days.

They were not cannon shots. They were the opening sounds of the largest volcanic eruption in modern human history.

On the evening of 10 April 1815, Mount Tambora on the small Indonesian island of Sumbawa entered its climactic phase. The volcano ejected approximately 160 cubic kilometres of pulverised rock, ash, and pumice into the atmosphere over the following 24 hours, sent a column of ash and sulphur dioxide approximately 43 kilometres into the stratosphere, and reduced its own mountain in height from approximately 4,300 metres to approximately 2,850 metres. The pyroclastic flows that descended the mountain’s flanks killed approximately 11,000 people in the surrounding region directly, in the first day of the event. The famines and disease that followed across the Indonesian archipelago over the next several months killed approximately 60,000 to 80,000 more.

The eruption was, by the available geological measurements, a Volcanic Explosivity Index 7 event, the highest VEI rating documented in modern human historical records since the eruption of Mount Samalas in Indonesia in 1257. The sulphur dioxide injected into the stratosphere spread around the planet over the following months, where it converted to sulphate aerosol and reflected solar radiation back into space. The consequences of that radiative shift, on the available climate evidence, were felt across every continent in the Northern Hemisphere over the subsequent two years.

The mechanism

A peer-reviewed climate model reconstruction of the Tambora eruption, published in 2017 in Nature Communications by John Fasullo and colleagues at the National Center for Atmospheric Research, established the basic physical pathway through which a single volcanic eruption on a small Indonesian island could disrupt the climate of the entire Northern Hemisphere. The eruption injected approximately 60 million tonnes of sulphur dioxide into the stratosphere, which is the upper layer of the atmosphere above approximately 10 kilometres altitude where there is no weather to wash particles back to the surface. The sulphur dioxide converted to sulphate aerosol over the following weeks and months, forming a thin reflective layer that spread around the planet on the prevailing stratospheric circulation.

The sulphate aerosol layer reflected approximately 6 watts per square metre of incoming solar radiation back into space at its peak, on the Fasullo team’s modelling. The result was a measurable cooling of the planet’s surface by approximately 0.4 to 0.7 degrees Celsius averaged across 1816, with substantially larger regional anomalies in the Northern Hemisphere where the cooling concentrated in the summer growing season. The cooling was not uniform. It was unusually severe in northeastern North America, in western and central Europe, and in scattered parts of Asia, where the combination of stratospheric aerosol cover and disrupted atmospheric circulation produced the coldest summer recorded in approximately two centuries.

The Fasullo team’s analysis also identified secondary effects in the ocean and the cryosphere. The sea surface in the North Atlantic cooled measurably, the Arctic sea ice extended further south than the modern average, and the changes in surface temperature gradients altered the prevailing wind patterns over Europe and North America. The 1816 climate disruption was, on the available evidence, not simply a cold year. It was a fundamental reorganisation of atmospheric and oceanic circulation that took approximately two years to dissipate.

The year without a summer

The summer of 1816 was, in the lived experience of people in the affected regions, unlike anything they had ever encountered. In New England, frost fell every month of the year. Crops planted in the spring froze in June and again in July and again in August. The harvest of 1816 across northern New England was substantially less than half of normal, and in many communities was almost entirely lost. The price of wheat in the region more than doubled. The price of oats, used to feed horses on which all overland transport then depended, increased by approximately 800 per cent over the following winter.

In western and central Europe, the same pattern unfolded with similar severity. The 1816 harvest in France, Switzerland, the German states, and the United Kingdom failed across most major crops. Bread prices in some affected regions doubled within months. Riots over food broke out in Ireland, Wales, England, France, and Switzerland during the autumn and winter of 1816 and into 1817. The Swiss government declared a national emergency. The British government dispatched soldiers to suppress food riots in the manufacturing towns of the Midlands.

The death toll in Europe and North America during 1816 and 1817 from famine and the diseases that followed it was substantial but is difficult to determine precisely from the surviving records. Historical demographic studies have estimated approximately 100,000 to 200,000 excess deaths in Europe alone from famine, typhus, and other epidemic diseases in the two years following the eruption. The combined death toll from the direct eruption and the subsequent climate-driven famine and disease was, on the available estimates, well in excess of the 90,000 figure most commonly cited for the eruption itself.

The cholera connection

In 1817, in the Bengal region of British India, an outbreak of a previously regional disease began to spread along trade routes in a pattern that had not been observed before. The disease was Vibrio cholerae infection, which had been endemic in the Ganges Delta for centuries without major geographic expansion. In 1817 and 1818, it spread for the first time outside South Asia, reaching Southeast Asia, the Middle East, East Africa, and southern Europe through maritime trade routes and pilgrim caravans. The first global cholera pandemic, which would kill millions of people across Asia, Europe, and the Americas over the following decades, had begun.

The causal connection between the Tambora climate disruption and the emergence of the first cholera pandemic is suggestive rather than definitively established. The peer-reviewed epidemiological evidence, however, points to several plausible pathways. The climate disruption in South Asia in 1816 and 1817 included anomalous monsoon patterns that altered the salinity and temperature of estuarine waters in the Ganges Delta where Vibrio cholerae lives in its environmental reservoir. The disruption may have produced a strain variant with enhanced epidemic potential, or may have altered human population movements and water supplies in ways that facilitated the disease’s geographic expansion. The precise mechanism is contested in the peer-reviewed literature, but the temporal coincidence between the Tambora climate disruption and the emergence of cholera as a global disease is striking enough that the connection is treated as plausible in the standard epidemiological histories.

Frankenstein at Lake Geneva

In May 1816, a small group of British travellers arrived at the Villa Diodati on the shores of Lake Geneva in Switzerland. The group included the poet Percy Bysshe Shelley, his 18-year-old companion Mary Wollstonecraft Godwin, her stepsister Claire Clairmont, the poet Lord Byron, and Byron’s personal physician John Polidori. The plan had been to spend the summer of 1816 in the mountains, walking, sailing, and writing.

The summer at Lake Geneva did not unfold according to plan. The weather throughout June and July 1816 was, in Mary Godwin’s own description, “ungenial.” Cold rain fell for weeks at a time. Storms produced lightning across the lake almost nightly. The group was confined to the villa for days at a stretch by weather conditions that prevented outdoor activity of any kind. Lord Byron proposed, during one of these confinements, that each member of the group should write a ghost story to pass the time.

Mary Godwin, who would marry Percy Shelley later that year and become Mary Shelley, began work on a story about a scientist who reanimates dead tissue to create a living human being. The story expanded into a full novel over the following twelve months. Frankenstein, or The Modern Prometheus was published anonymously in 1818. Byron’s contribution to the same evening’s competition expanded into “Darkness,” one of the most haunting poems in the Romantic tradition, which begins with the line “I had a dream, which was not all a dream” and proceeds to describe a world in which the sun has been extinguished and the surviving humans are reduced to scavenging among the ruins. Polidori’s contribution became “The Vampyre,” the foundational text of modern vampire fiction.

The literary record of the summer of 1816, on the strongest available reading of the contemporary correspondence and diaries, was substantially shaped by the weather the visitors at the Villa Diodati were experiencing. The unending storms, the failed harvests, the death of livestock in nearby fields, and the visible distress of the local population would all have been part of the daily atmosphere in which Frankenstein, “Darkness,” and “The Vampyre” were composed. The works are not literal descriptions of the climate of 1816, but they were written by people inhabiting a world that had been visibly disrupted by something none of them yet understood.

The island record

A 2023 peer-reviewed study by Nick Wilson at the University of Otago and colleagues, published in Scientific Reports, examined the impact of the Tambora eruption on a global sample of 31 large populated islands. The team analysed contemporary climate records, historical demographic data, and modern climate model reconstructions to test the breadth of the eruption’s effects. The result was that 29 of the 29 islands with sufficient surviving data showed measurable weather and climate anomalies in the 1815 to 1817 period. The disruption was not regional. It was global, and it touched every populated region of the Northern Hemisphere for which records survive, with substantial measurable effects in parts of the Southern Hemisphere as well.

The Wilson team’s secondary purpose was to use the Tambora event as a case study for what a comparable future eruption might do to modern global civilisation. Their analysis suggests that island nations may have some long-term survival value during sun-blocking catastrophes of this kind, because the moderating influence of surrounding ocean reduces the severity of local cooling compared with continental interiors. The Fasullo 2017 modelling, however, suggested the opposite outcome for a future analogous eruption occurring under conditions of contemporary global warming. The increased ocean stratification produced by anthropogenic warming, on the Fasullo modelling, would amplify rather than dampen the surface cooling response to a major volcanic event.

The honest limitations

Several methodological caveats apply to the literature described above.

The exact death toll of the Tambora eruption is genuinely uncertain. The 90,000 figure most commonly cited is the sum of approximately 11,000 direct pyroclastic-flow deaths and approximately 80,000 deaths from famine and disease across the Indonesian archipelago in the months following the eruption. The figure is based on incomplete colonial-era population estimates and may be substantially understated. Death tolls from the European and North American famine of 1816 and 1817 are also approximate and depend on assumptions about background mortality rates that vary across the affected regions.

The causal connection between the Tambora climate disruption and the first global cholera pandemic is plausible but not definitively established. Cholera could have emerged as a global pandemic for reasons unrelated to the volcanic climate disruption, and the temporal coincidence between the two events does not by itself prove a causal relationship. The peer-reviewed epidemiological literature treats the connection as suggestive rather than confirmed.

The literary record of the summer of 1816 at Lake Geneva is contemporaneous and well-documented, but the causal claim that Frankenstein would not have been written without the Tambora eruption is unprovable. Mary Shelley was a writer of extraordinary capability working in a Romantic literary tradition that had been engaging with themes of nature, reanimation, and human limits for decades before 1816. What can be said with confidence is that the specific conditions under which she began Frankenstein were produced by the Tambora climate disruption, and that the atmosphere of the novel reflects the atmosphere of the summer in which it was conceived.

What it means

Several things follow from the Tambora evidence that are worth saying clearly.

The first is that a single volcanic eruption on a small Indonesian island can, under the right conditions, disrupt the climate of the entire Northern Hemisphere for more than a year, kill substantially more than 100,000 people across multiple continents through cascading consequences, and reshape the political, economic, and literary history of the early nineteenth century. The Tambora event is not a hypothetical or a model. It is a documented historical case of how a relatively brief geological event can produce sustained global human consequences on a scale that the popular framing of volcanic eruptions does not typically include.

The second is that the population of the world in 1815 was approximately 1 billion people. The population of the world in 2026 is approximately 8.2 billion. The agricultural systems on which modern populations depend are, on most relevant measures, more efficient and more productive than those of the early nineteenth century. They are also more centralised, more dependent on global trade networks, and more vulnerable to simultaneous disruption in multiple regions than the agricultural systems of 1815. A Tambora-magnitude eruption occurring under modern conditions would, on the Fasullo 2017 modelling, produce a substantially larger surface cooling than the 1815 event produced, in part because of ocean stratification changes driven by anthropogenic warming.

The third is that VEI 7 eruptions occur, on the available geological record, approximately once every several hundred to one thousand years. The Samalas eruption of 1257 was VEI 7. The Tambora eruption of 1815 was VEI 7. The next VEI 7 eruption, on the available statistical evidence, is more likely than not to occur within the next several centuries. The geological systems involved are not predictable on human time scales, and the next event could occur tomorrow, or could occur in 800 years. What is clear from the peer-reviewed record is that the next event will produce consequences comparable to the 1815 Tambora eruption, on a planet substantially less prepared for them than the world of 1815 was.

The fourth, on the strongest current reading of approximately two centuries of geological, climatological, demographic, and literary evidence, is that the most consequential single event in the early nineteenth century may have been a geological one in a place that almost no one in Europe or North America had ever heard of, and the most enduring literary record of that event is a novel about a scientist who creates a living being out of dead matter and then cannot bring himself to recognise it as his own.

Mary Shelley was eighteen years old when she began writing Frankenstein.

The volcano had erupted the previous April.

The summer at Lake Geneva was the coldest in living memory, and nothing in the world that summer was behaving as anyone had expected it to.

The post The 1815 eruption of Mount Tambora in Indonesia, the largest documented volcanic eruption in human history, killed approximately 90,000 people directly and produced the year without a summer in 1816, a climate disruption that caused famine across the Northern Hemisphere, may have triggered the first global cholera pandemic, and produced the cold dark summer at Lake Geneva during which Mary Shelley wrote Frankenstein appeared first on Space Daily.

A modelling study published in Communications Earth & Environment in June 2025 found that the West Antarctic Ice Sheet could begin an irreversible collapse at ocean temperatures between zero and 0.25°C above current levels — meaning the threshold may have already been reached

Once the collapse begins, the authors argue, it would be self-sustaining: not a process that could be halted by subsequent emissions reductions, but one that would continue until the ice sheet had contributed roughly four metres to global sea levels. That contribution would unfold over centuries to millennia. The study is one modelling paper, not a settled consensus, but the threshold it identifies is lower than many prior estimates, and the mechanism it describes is worth examining closely.

The authors are David Chandler, Petra Langebroek, Ronja Reese, Torsten Albrecht, Julius Garbe, and Ricarda Winkelmann, working across the Potsdam Institute for Climate Impact Research, the Norwegian research centre NORCE, and Northumbria University. To examine how the ice sheet has responded to past conditions, they ran model simulations extending back 800,000 years, giving the analysis a long baseline of Antarctic ice sheet behaviour against which to calibrate the projections.

What the threshold means

The 0.25°C figure refers to ocean warming at depth around West Antarctica, not to global average surface temperature. The distinction matters. Ocean temperatures in the Amundsen Sea, which washes against the base of the West Antarctic glaciers, have already been rising as warmer Circumpolar Deep Water intrudes further onto the continental shelf. The study does not claim that threshold has been crossed; it identifies where, in the model, collapse becomes self-sustaining.

The mechanism at the centre of the analysis is marine ice sheet instability. The West Antarctic Ice Sheet sits largely on bedrock below sea level. Its glaciers are held in place partly by ice shelves, floating extensions of the sheet that buttress the flow of ice toward the ocean. As warm water undercuts those shelves, they thin. As the grounding line, where the glacier meets the ocean floor, retreats into deeper water, the geometry of the ice sheet becomes less stable. In this configuration, retreat can accelerate under its own weight without requiring additional external warming to continue.

This is the self-sustaining character the paper describes. Beyond the 0.25°C threshold in the model, the process continues even if ocean temperatures were to stop rising. The four metres of sea-level rise is not a peak that would be reached and then reversed; it is the new equilibrium state the ice sheet would settle toward over the following centuries and millennia.

What the paper does not show

This is one modelling study, not settled consensus. The result should be taken seriously, but it should not be read as the final word on the timeline, the precise threshold, or the certainty of collapse.

Modelling the West Antarctic Ice Sheet involves choices about ice physics, ocean forcing, and bedrock properties that different research groups represent differently. Other recent work has reached varying conclusions about how close the system currently sits to a tipping point, and the question of whether the ice sheet has already been destabilised is actively debated in the literature. A 2023 paper from a separate group concluded the sheet had not yet been pushed past tipping, while noting the path toward it was concerning.

The 800,000-year baseline the team used is a strength of the analysis, providing a longer view of how the ice sheet has behaved under past climate states than most studies can offer. But extrapolating from past behaviour to future response under conditions that may be outside the range of the historical record carries its own limitations, and the authors acknowledge these.

The asymmetry of the timescales

One detail in the paper that the coverage has noted is the asymmetry between the timescale of destabilisation and the timescale of ice sheet growth. It takes tens of thousands of years for a large ice sheet to accumulate. The conditions that could initiate collapse can be reached in decades. The four metres of sea-level rise would then play out over centuries. That sequence has a particular character: a fast trigger, a slow-moving consequence, and a very long tail.

Four metres of sea-level rise distributed over centuries is not an outcome that falls within ordinary planning horizons. It is an outcome that would affect coastlines and populations far beyond any current infrastructure’s design life. The paper frames the next few years as a period in which the trajectory of deep ocean warming around Antarctica will become clearer, and in which emissions choices will continue to influence where the system ends up relative to the threshold the model identifies.

What to watch

The Amundsen Sea embayment, where Thwaites and Pine Island glaciers are already showing significant grounding-line retreat, is the region the paper’s concerns centre on most directly. Ongoing observational work on those glaciers, including the International Thwaites Glacier Collaboration’s field campaigns, will provide ground-truth data against which modelling results like these can be tested.

Whether observed ocean temperatures at depth around West Antarctica are approaching the 0.25°C increment the study identifies, and how quickly, is a question the oceanographic record will continue to answer over the next several years.

The post Scientists say the West Antarctic Ice Sheet could collapse with very little additional warming and the four metres of sea level rise that would follow cannot be stopped once it begins appeared first on Space Daily.

In a groundbreaking advancement for climate-based daylight modeling, researchers Aw, Leng, and Lim have developed an innovative Principal Component Analysis (PCA)-based climatic similarity index designed specifically to enhance weather file selection criteria in tropical climates. This pioneering study, published in Scientific Reports in 2026, not only addresses the critical challenge of accurately simulating daylight conditions in regions characterized by complex tropical weather patterns but also marks a significant leap forward in climate-driven architectural and environmental modeling.

Tropical climates are notoriously difficult to model due to their inherent variability and a rich tapestry of meteorological phenomena, including high humidity, fluctuating cloud cover, intense rainfall, and dynamic solar radiation patterns. Traditional weather file selection methods often fall short in capturing this complexity, which can lead to inaccuracies when used as inputs for climate-based daylight simulations. It is precisely this gap that the PCA-based climatic similarity index aims to bridge, by offering a sophisticated, data-driven method to select representative weather files that better mirror the actual climatic nuances of tropical regions.

At the core of this new method lies Principal Component Analysis, a powerful statistical tool that reduces the dimensionality of large, multivariate datasets while preserving the most critical variances within the data. By applying PCA to a wide array of climatic variables—such as temperature, humidity, solar radiation, wind speed, and cloud cover—the researchers extracted patterns that effectively distill the complexity of tropical weather into manageable, representative components. This dimensionality reduction facilitates the identification of weather days or periods that are climatically similar, which can then be selectively employed in daylight modeling simulations to enhance their fidelity.

One of the most striking aspects of this research is its focus on tailoring the index specifically for tropical environments. Unlike temperate or arid regions, tropical climates present a unique set of challenges due to their lack of distinct seasons, diverse microclimates, and frequent convective weather events. The PCA-based similarity index developed in this study accommodates these factors by incorporating variables sensitive to the high variability and transient nature of tropical weather, thereby offering a bespoke solution rather than a one-size-fits-all approach.

Implementing this index drastically improves the selection of weather files for daylight modeling. Instead of relying on standardized Typical Meteorological Year (TMY) datasets, which might not sufficiently capture the local climatic variability, the index enables the identification of the most climatologically representative data points. Consequently, simulations built on these carefully curated datasets demonstrate markedly improved accuracy in predicting daylight performance, solar heat gains, and glare potential—parameters crucial for the optimization of building energy efficiency, occupant comfort, and environmental impact in tropical architecture.

The implications of this development extend beyond just daylight modeling. Because accurate weather file selection is foundational for a host of building performance simulations, the PCA-based climatic similarity index holds promise for applications in thermal comfort analyses, energy consumption forecasting, and even in the design of adaptive building envelopes that respond dynamically to changing climatic conditions. By improving the input data quality, the model ensures that downstream simulation outputs are more reliable and relevant to real-world scenarios.

Technically, the process begins by assembling an extensive local weather dataset comprising high-resolution meteorological measurements collected over multiple years. The researchers then preprocess the data to address missing values and normalize the variables, ensuring that the subsequent PCA accurately reflects genuine climatic patterns rather than artifacts or biases. The PCA is executed to derive principal components that quantify the dominant modes of variability in the dataset. Each weather day is then scored based on these components, facilitating clustering or similarity assessments.

The novel similarity index is computed by measuring the Euclidean distance between weather days in the principal component space, enabling the quantification of climatic resemblance. Days with the smallest distances are deemed most similar, allowing researchers and practitioners to construct weather file subsets that authentically capture the spectrum of climatic conditions typical for the region. This approach reveals weather analogues that traditional chronological or statistical selection methods might overlook.

To validate the performance of their index, the authors integrated it within a daylighting simulation framework and compared simulation outcomes using weather files selected via their method against those obtained from standard TMY and random selections. The results showed improved correlation with observed daylighting metrics, reduced simulation uncertainty, and an enhanced capacity to capture extreme weather events that significantly influence daylight availability and building performance in the tropics.

This methodological innovation also paves the way for more robust scenario-based simulations in the context of climate change. As tropical regions face increasing variability due to global warming, having a dynamic, adaptable index that can recalibrate weather file selection in response to shifting climatic baselines becomes essential. The PCA-based similarity measure offers a flexible tool to explore the impacts of future climate scenarios on daylight and building performance, supporting resilience and adaptation strategies.

Moreover, this approach is transferable to other climate-based modeling domains. While the current work focuses on daylighting, the underlying mathematical framework could be repurposed for selecting representative weather data in hydrological models, urban microclimate assessments, and even in renewable energy generation forecasting where tropical climate variability plays a critical role.

The researchers emphasize the importance of open data and algorithm transparency, ensuring that the index can be implemented in open-source simulation tools frequently used by the building performance community. This accessibility enhances the potential for widespread adoption, community-driven refinement, and integration into international building standards addressing tropical architecture.

In conclusion, Aw, Leng, and Lim’s development of a PCA-based climatic similarity index represents a vital advancement for climate-sensitive modeling in tropical regions. By refining the selection of weather files, their work promises to improve the accuracy and reliability of daylight simulations, contributing to more sustainable, comfortable, and energy-efficient building designs. As tropical cities grow rapidly and strive to meet sustainability goals, such innovative tools become invaluable for architects, engineers, and policymakers navigating the complexities of climate-responsive design.

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Subject of Research: Development of a Principal Component Analysis-based climatic similarity index for enhanced weather file selection in climate-based daylight modeling in tropical climates.

Article Title: Development of a PCA-based climatic similarity index to enhance weather file selection criteria for climate-based daylight modelling simulations in tropical climates.

Article References:
Aw, S.B., Leng, P.C. & Lim, Y.W. Development of a PCA-based climatic similarity index to enhance weather file selection criteria for climate-based daylight modelling simulations in tropical climates. Sci Rep (2026). https://doi.org/10.1038/s41598-026-58112-x

Image Credits: AI Generated

A team led by Thomas Evans-Soma of the Max Planck Institute for Astronomy in Heidelberg has published observations of the exoplanet WASP-121b that complicate the existing picture of how chemistry moves through an ultra-hot atmosphere. Using the James Webb Space Telescope’s Near-Infrared Spectrograph to watch the planet through a complete orbit of its host star, the team detected methane in abundance on the planet’s nightside. On the dayside, temperatures reach approximately 3,000°C, well above the point at which iron vaporises. Methane, a molecule that decomposes far below that threshold, should not survive the heat. The paper was published in Nature Astronomy in June 2025.

The detection itself is the straightforward part. The explanation is not.

What the JWST data showed

WASP-121b is a tidally locked gas giant orbiting its star in about 30 hours, close enough that one face is always turned toward the heat. The dayside atmosphere, at roughly 3,000°C, is hot enough to break apart most molecules and sustain metals in vapour form. Water, carbon monoxide, and silicon monoxide were all detected there, the last of these making WASP-121b the first planet in which silicon monoxide has been identified in any atmosphere.

The nightside, while still extreme by any ordinary measure, sits at considerably lower temperatures. It was there that the team found methane in concentrations high enough to register clearly in the spectroscopic data. Methane typically breaks apart under heat well below what the dayside experiences. Even on the nightside, the temperatures are sufficiently elevated that methane’s persistence requires an active replenishment mechanism. Without one, the molecule would deplete faster than the atmosphere could sustain it.

The circulation the models did not predict

The explanation Evans-Soma’s team proposes is vertical atmospheric circulation: strong upward winds lifting methane-rich gas from deeper, cooler layers of the nightside atmosphere to replace what is continuously being destroyed at higher altitudes. Deeper in the nightside atmosphere, where temperatures are lower and the planet’s carbon-to-oxygen ratio works in methane’s favour, the molecule forms readily. The proposed circulation carries it upward fast enough to maintain the observed concentration.

The problem is that this kind of vigorous vertical mixing was not predicted by existing atmospheric models for planets in this temperature range. The standard picture of ultra-hot Jupiter dynamics has tended to emphasise horizontal circulation, with hot gas flowing from the dayside to the nightside at high altitudes and cooler gas returning at lower levels. Strong vertical mixing on top of that, specifically on the nightside, was not part of the expected behaviour.

The authors are careful to frame this as a proposal. The methane detection is robust; the vertical circulation as its cause is the team’s interpretation, and the models will need to be tested against the new data before the picture can be called settled. In the authors’ framing, the finding indicates that existing dynamical models will likely need to be adapted to account for the degree of vertical mixing the nightside data appears to require.

What the silicon monoxide finding adds

The detection of silicon monoxide on the dayside is a separate result worth noting in its own right. Silicon monoxide has not previously been identified in any planetary atmosphere, exoplanet or otherwise. Its presence at the temperatures and pressures of WASP-121b’s dayside is consistent with the conditions that would vaporise silicate minerals from deeper layers and carry the products to detectable altitudes.

This is the kind of detail that matters when building out a coherent picture of how ultra-hot gas giants differ chemically from anything in our solar system. The JWST’s NIRSpec instrument has now made it possible to run a reasonably complete inventory of the major carbon, oxygen, and silicon compounds across a planet’s full orbital phase, which is what Evans-Soma and Gapp did here. The dayside and nightside of WASP-121b turn out to carry chemistries that are not just different in degree but qualitatively distinct from each other.

What this means for the models

Ultra-hot Jupiter dynamics are a young field, and the models built so far have been calibrated against a limited set of observations. WASP-121b is one of the most intensively studied exoplanets in this class, partly because its tight orbit and high temperature make its atmosphere accessible to spectroscopic observation from a range of instruments over many years.

The challenge the new paper poses is specific: how does an atmosphere this hot maintain the chemical gradients the data shows, and what is driving the vertical circulation that appears necessary to explain the nightside methane? Those questions will determine what adjustments atmospheric modellers need to make, and whether the circulation observed here is particular to WASP-121b’s conditions or something common across the ultra-hot Jupiter population. The paper does not resolve that question. It opens it.

The post An exoplanet with a daytime temperature hot enough to vaporize iron has methane on its nightside because of an atmospheric circulation that should not be able to exist at that heat appeared first on Space Daily.

The Arctic Ocean has had ice on it, in some form, for essentially the entire span of recognisably modern human existence. The most recent interglacial period warm enough to have melted the summer ice cap was the Eemian, approximately 130,000 to 115,000 years ago, during which paleoclimate evidence suggests the Arctic was seasonally ice-free at its summer minimum — most clearly during the warmest phase around 130,000 years ago, with conditions gradually cooling toward the end of the period around 115,000 years ago, when the Arctic returned to continuous year-round ice cover. The Eemian ended before any sustained migration of anatomically modern humans out of Africa, before the development of agriculture, before recognisable language families had differentiated, before the construction of the first permanent settlements, and before essentially every aspect of human society that the present civilisation rests on. For approximately the past 115,000 years — through the entire emergence of modern civilisation — the Arctic has carried summer ice. That period is now ending. By the most recent peer-reviewed projections, the first single year in which the Arctic Ocean drops below the technical threshold for “ice-free” status — defined as less than 1 million square kilometres of sea ice, compared to the historical summer minimum of approximately 5 to 7 million square kilometres — is likely to occur sometime in the 2030s.

According to a 2023 study in Nature Communications by Seung-Ki Min and colleagues at Pohang University and the University of Hamburg, the projected date of the first ice-free Arctic September is now substantially earlier than the IPCC’s 2021 Sixth Assessment Report had concluded. The 2021 IPCC report had projected ice-free conditions “near mid-century” under intermediate and high emissions scenarios, with substantial uncertainty under low-emissions scenarios. Min and colleagues reanalysed the underlying climate models using observational constraints — adjusting the model projections to match the actual rate of Arctic sea ice decline measured by satellites over the past four decades — and concluded that the first ice-free September will likely occur in the 2030s under all emissions scenarios, including the most ambitious low-emissions trajectory. In the words of Dirk Notz, one of the study’s authors and a contributor to the IPCC reports: “We basically are saying that it has become too late to save the Arctic summer sea ice.”

What “ice-free” actually means

The technical definition of “ice-free” in this context is not the literal absence of all sea ice. As reported by a 2024 synthesis review of ice-free Arctic projections in Nature Reviews Earth & Environment, the threshold researchers use is sea ice area below 1 million square kilometres — substantially less than the approximately 4 to 7 million square kilometres that has been the typical late-summer minimum over the past several decades, but not literally zero. Some ice will continue to form along the northern coast of Greenland and within the Canadian Arctic Archipelago even after the central Arctic Ocean has lost its summer cover. The threshold is set at the level below which the central Arctic basin would be effectively open ocean during the September minimum — navigable, exposed to sunlight rather than reflecting it back, and fundamentally different in its physical, ecological, and atmospheric behaviour than the ice-covered Arctic that has characterised the Earth for approximately the last 115,000 years.

The first ice-free year is unlikely to be permanent. Winter ice will continue to form for some additional decades after the first ice-free summer, and there will be year-to-year variability in summer ice extent. But once the threshold has been crossed, it will be crossed with increasing frequency, and the long-term direction of travel is clear: the Arctic is heading toward a configuration in which late summer is reliably open water, with all of the consequences that flow from that change. A more recent 2024 paper in *Nature Communications* by Heuzé and colleagues projects that the first single ice-free day in the Arctic could occur even earlier than the first ice-free month — potentially before 2030, depending on whether an extreme weather year produces a sufficiently sharp summer melt.

Why the loss matters beyond the Arctic itself

The Arctic Ocean is not a self-contained system. The presence of summer ice across its surface is one of the major regulators of the global climate, and its loss will produce consequences across the planet. The most direct mechanism is the albedo effect: sea ice reflects approximately 80 percent of incoming sunlight back to space, while open ocean absorbs approximately 90 percent of it. Replacing ice with water at the top of the planet means substantially more solar energy is being absorbed into the Arctic Ocean, which then transfers that heat to the surrounding atmosphere, accelerates the warming of the broader Arctic region (which is already warming approximately four times faster than the global average), and propagates the change southward through atmospheric and oceanic circulation patterns.

Per a 2023 analysis in The Conversation of the implications of an ice-free Arctic, the downstream effects include disruption of mid-latitude weather patterns through changes to the polar jet stream (which is increasingly destabilised by the diminishing temperature gradient between the Arctic and lower latitudes); accelerated melting of the Greenland ice sheet (which contributes directly to sea-level rise, unlike sea ice itself); progressive thaw of Arctic permafrost (which releases methane and carbon dioxide stored in frozen organic matter, creating a self-reinforcing warming loop); collapse of Arctic ecosystems built around the seasonal sea ice cycle (including polar bears, ringed seals, walruses, ivory gulls, and the entire food web that depends on ice algae); and substantial disruption to the lives of the approximately 4 million people who live in the Arctic regions of the eight Arctic Council countries — including roughly 400,000 Indigenous people from more than 40 distinct ethnic groups, whose traditional food, transport, and cultural systems are particularly closely tied to a reliably frozen sea.

The geopolitical and economic dimensions

An ice-free Arctic will, simultaneously, open commercial shipping routes that have been closed for the entirety of recorded history. The Northern Sea Route along the Russian Arctic coast, the Northwest Passage through Canadian waters, and a potential central Transpolar route across the open polar ocean will all become reliably navigable during summer months. Container ships travelling from Northeast Asia to Northern Europe will be able to save approximately 40 percent of the distance compared to the traditional Suez Canal route. Energy resources currently inaccessible beneath the Arctic seafloor — estimated at approximately 13 percent of the world’s undiscovered oil and 30 percent of its undiscovered natural gas — will become commercially extractable. Russia, the United States, Canada, Norway, Denmark (via Greenland), and increasingly China (which has declared itself a “near-Arctic state”) are now actively positioning themselves for the strategic competition that an open Arctic Ocean will produce.

The threshold itself, when it is crossed sometime in the next 15 years, will not look dramatic from any vantage point available to most people. It will appear as a satellite image showing slightly less ice than the previous year. It will be reported as a single statistical metric falling below a defined value. The lived experience of most humans alive on the planet at the time will be substantially unchanged on the day of the threshold crossing. But the underlying transition is one of the larger physical changes to the planet that any modern human society has lived through — a return, after approximately 115,000 years, to a configuration of the polar regions that predates the entire arc of recognisably modern human civilisation. The species will, within the lifetimes of most people reading this, become the first generation to witness an Arctic Ocean without its summer ice. The change will not be reversible on any timescale relevant to human institutions. The question is no longer whether it happens but precisely when, and how rapidly the societies that depend on the old configuration adapt to the new one.

The post Most people alive today will live to see the Arctic Ocean lose its summer ice — for the first time since before our species left Africa, 115,000 years ago appeared first on Space Daily.

Rising seas could turn mangroves from carbon-storing climate allies into unexpected carbon emitters. Mangroves are among the most effective natural systems for capturing and storing carbon, but new research suggests that rising sea levels could significantly reduce that benefit and may even cause these coastal forests to release carbon in the future. Made up of [...]

It feels like there's no escaping AI right now, whether you’re trying to type a sentence without being interrupted by a digital “assistant” or struggling to find a new refrigerator that doesn’t require a Wi-Fi connection for some reason. You’d be forgiven for wondering if we’re in the midst of a quantum leap in tech or whether people are just hyping up a heap of slop.

So what should we make of the growing use of AI in weather and climate modeling?

The conversation didn't get off to a great start earlier this year when a National Weather Service office posted a forecast map featuring nonexistent cities in Idaho with names like “Whata Bod” and “Orangeotild.” Thankfully, that was just an AI-generated image produced for social media, not the actual forecast model. Meteorologists and climate scientists are not yet being replaced by large language model prompt engineers.

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According to predictions from weather organizations across the planet, a super El Niño weather event is likely to begin over the next few weeks. It’s predicted to drive up temperatures across the globe, bringing increased chances of heatwaves, drought, wildfires, and even famines – plus, this year’s El Niño is likely to be stronger than usual, making those effects worse. Let’s take a look.

Scientists say melting sea ice may have pushed the Arctic Ocean past a tipping point, triggering changes that could reshape marine life for decades. Scientists have identified what appears to be a major and potentially irreversible change in the Arctic Ocean. According to a new study, climate-driven sea ice loss has altered the region’s chemistry [...]

The years 2023 and 2024 were the warmest on record, coinciding with a powerful Pacific climate event known as El Niño. El Niño is the warm phase of a natural climate cycle in which surface waters in the eastern Pacific are unusually warm, bringing record-breaking heatwaves in the Amazon and heavy rainfall in the southern USA. Its counterpart, La Niña, is the cool phase that brings wetter conditions to the Northern USA. 

In a typical El Niño, warm water in the eastern Pacific weakens the winds blowing westward across the tropical Pacific, known as trade winds, allowing more warm water to flow eastward – a self-reinforcing cycle that amplifies the event. However, the 2023 El Niño differed because the ocean warmed intensely, but the trade winds remained strong. Researchers from the Scripps Institution of Oceanography, led by Qihua Peng and Shang-Ping Xie, recently investigated how and why this unusual event occurred.

First, the researchers tracked how air pressures changed across the Pacific during the event using a metric calculated by NOAA, known as the Southern Oscillation Index. When the eastern Pacific warms during an El Niño, the difference in air pressure across the Pacific typically decreases. In 2023, they found that temperatures in the eastern Pacific rose to more than 3°F (2°C) above normal, yet the drop in air pressure was only about 31% as strong as they expected. They also calculated that changes in wind speed and direction could only account for about 30% of the warming. So why was the 2023 El Niño so strong?

To answer this question, the research team then looked beyond the Pacific, analyzing sea surface temperatures from NOAA satellite data. They found that the North Atlantic and Indian Oceans also experienced record-breaking heat in 2023, with temperatures in the North Atlantic exceeding 2°F (1°C) above normal – the warmest in recent history. This suggested that El Niño events can develop in response to ocean conditions worldwide, not just those in the Pacific.

Next, the team used a computer program that simulates how the atmosphere responds to ocean temperatures, called the Community Atmosphere Model, to examine how heat from other oceans affects the Pacific. They found that heat in the North Atlantic and Indian Oceans generated large columns of hot air rising over those regions. This air cooled at high altitudes and then sank over the central Pacific, strengthening a large-scale loop of rising and sinking air that drives trade winds westward. Strengthening this circulation worked against El Niño by keeping trade winds blowing westward about 30% more strongly than Pacific warming alone would have. If the trade winds remained strong, why was the eastern Pacific so warm in 2023?  

To answer this question, the researchers studied 3 consecutive La Niña years between 2020 and 2023, analyzing ocean temperature and sea level data from NOAA’s Global Ocean Data System. During those years, strengthened trade winds transported heat into the western Pacific. As the seawater got warmer, it expanded, a process known as thermal expansion. Over those 3 years, thermal expansion and constant wind created a “pile” of warm water in the western Pacific, which reached its highest level of stored heat since 1982. When the trade winds eventually relaxed as La Niña faded, this piled-up warm water surged eastward, setting the stage for the El Niño event.

To test whether this stored heat alone could drive an El Niño, the team used a computer program that models oceanic and atmospheric interactions, called a coupled general circulation model. They input observed ocean temperatures from April 1, 2023, when La Niña ended, but removed all wind changes after that date. Their model successfully reproduced 87% of the warming observed between June and December 2023, which suggested that trade winds contributed just 13%. Stored heat was carried eastward by massive underwater waves traveling along the equator. As these waves reached the Eastern Pacific, they pushed cold water deeper, allowing surface water to warm. The researchers concluded that this oceanic process drove the 2023 El Niño to develop without the usual wind-driven feedback.

The team suggested that in a warming world, large heat reservoirs in the western Pacific will likely become more common, leading to more frequent strong El Niños. However, because their analysis focused on a single event, it remains unclear how often El Niños develop through oceanic processes alone. Ultimately, their study showed that the ocean can be more than a passive partner in El Niño – it can be the driving force.

The post Why the 2023 El Niño broke records appeared first on Sciworthy.