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SummaryGeocenter motion, defined as the displacement of Earth’s center of mass relative to its center of figure, is crucial for maintaining the International Terrestrial Reference Frame origin and quantifying large-scale mass redistribution. However, whether observing geocenter motion by tracking satellite orbits or inferring it using geophysical models, accurately acquiring such subtle motions imposes stringent requirements on the consistency and precision of both tracking data and geophysical models. This study improves geocenter motion estimates derived from the combination of GRACE/GRACE-FO time-variable gravity (TVG) and Ocean Bottom Pressure (OBP) models (the GRACE-OBP method) in two ways. First, we apply a forward modelling technique to mitigate land–ocean leakage in GRACE/GRACE-FO TVG fields, which demonstrably outperforms empirical coastline buffer-zone corrections in controlled simulation experiments. Second, we introduce the Bayesian Three-Cornered Hat (BTCH) method to optimally combine geocenter series derived from multiple GRACE solutions and two independent OBP models (ECCO2 and MPIOM), producing an improved geocenter product without requiring a ground-truth reference. Uncertainty analysis shows that the noise level is governed primarily by the GRACE solution, and that BTCH provides a clearer advantage over equal-weighted averaging when the number of input series is limited, reducing the noise level by about 30 per cent. After restoring atmospheric and oceanic contributions, our improved geocenter series shows good agreement with the CSR SLR-derived geocenter product. Although uncertainty levels vary among individual solutions, the estimated annual and secular trend signals are broadly consistent and show limited sensitivity to the choice of GRACE TVG solution and OBP model. Using the improved geocenter series, we revisit the annual geocenter oscillation and its drivers; the results indicate that cryospheric mass variability and land-ocean mass exchange (i.e. sea-level fingerprints) provide non-negligible contributions to the annual geocenter cycle and improve consistency with observations. Finally, the improved geocenter series yields the lowest uncertainty in degree-1 mass variations, with a global RMS of 0.55 mm. Incorporating these degree-1 terms into mass budget assessments yields secular trends of 38.8 Gt/yr for the Antarctic Ice Sheet and 0.57 mm/yr for global mean ocean mass, highlighting the need for accurate geocenter corrections to support reliable long-term climate monitoring.

A research team at The Hong Kong University of Science and Technology (HKUST) has analyzed 40 years of data covering about 1,500 tropical cyclones and discovered that average rain rates surge by more than 20% in the 60 hours before landfall. The study is also the first to clearly identify the physical mechanisms behind this increase, showing that rising humidity over coastal areas and enhanced land-sea frictional contrasts strengthen convection, intensifying rainfall ahead of landfall. The results provide valuable insights for improving coastal disaster preparedness and early-warning systems.

Particles in the atmosphere, known as aerosols, cool the climate by acting as cloud condensation nuclei. The more cloud droplets form around these particles, the less sunlight penetrates a cloud. This cools the climate, although this process is outweighed by the much stronger greenhouse effect.

A leading climate scientist has sought to set the record straight over "demonstrably incorrect" claims made in a major U.S. government report that misrepresented his work and downplayed the role of human activity in global warming.

Wildfires in the northern boreal forests of Alaska, Canada, Scandinavia, and Russia may be more damaging to the climate than previously thought, a new UC Berkeley-led study suggests. That's because these fires don't just burn through trees; they can also penetrate deep into the carbon-rich layers of soil underneath many boreal forests, releasing carbon that has been accumulating for hundreds or even thousands of years.

The Cascadia Subduction Zone is unusually quiet for a megathrust fault. Spanning more than 600 miles from Canada to California, the fault marks the convergence of the Juan de Fuca and North American plates. While other subduction zones produce sporadic rumblings as the plates scrape past each other, Cascadia shows very little seismic activity, fueling assumptions that the plates are locked together by friction.

Changes in rainfall within global monsoon regions affect the livelihoods of billions. For years, climate models have suggested that the fingerprint of human-caused climate change on monsoons would become visible by a certain time. But what if that timeline is wrong? A new study published in Advances in Atmospheric Sciences suggests the signal may not emerge until a full decade later than previously estimated.

The South China Sea Throughflow (SCSTF) serves as a critical oceanic conveyor belt for heat and freshwater, mediating water exchanges between the South China Sea (SCS) and the Pacific and Indian oceans while regulating key processes such as heat and salt budgets, eddy activities, and marine biogeochemical cycles. It also plays a pivotal role in modulating the Indonesian Throughflow (ITF) and shaping climate variability across the Indo-Pacific. However, long-term direct observational data of the SCSTF have long been scarce, leaving its long-term changes under climate change and associated driving mechanisms poorly understood.

A research team led by University of Tsukuba has developed a new method to estimate long-term debris supply from steep slopes by measuring debris accumulated on decades-old abandoned roads. Debris supplied by rockfall and related slope processes is a key factor controlling the frequency and magnitude of debris flows. However, estimating the amount of debris supplied over several decades has been technically challenging.

Japan is an archipelago with diverse climate zones and complex topography that is prone to heavy rain and flooding. Add the growing effects of global warming. These disaster risks are heightened with an increased frequency and intensity of extreme precipitation events. Thus, predicting when and where these events might strike is crucial for future-proofing vulnerable infrastructure, especially in rural areas.

Cities are rapidly becoming the defining residential space of human life. Over 55% of the global population lived in urban areas in 2018, a proportion projected to reach nearly 68% by 2050, according to the United Nations (UN).

Greenland's largest glacier, Jakobshavn Glacier, may be edging closer to a critical threshold as meltwater runoff from the Greenland Ice Sheet accelerates in ways not seen in over a century, according to new research published in Climate of the Past. The study reconstructs more than 100 years of freshwater discharge flowing from the ice sheet into Disko Bay in western Greenland, revealing a striking and sustained change that began in the early 2000s.

In the summers of 2016 and 2017, a small research team endured harsh conditions on the Greenland Ice Sheet to gather data about the aerosols above it. These tiny particles carry crucial information about the elements that contribute to glacial ice loss, making them invaluable in the fight against climate change.

In a new study published in Environmental Science and Technology, this team reported that aerosols contain significant amounts of mineral dust, which can feed phosphorus to hungry, ice-melting algae.

“This study’s findings are important,” said Jasper Kok, an atmospheric physicist at the University of California, Los Angeles, who was not involved with the research. “The Arctic is warming several times faster than the global average,” he explained, and this warming exposes more bare soils that will only increase dust emissions.

Dusty Fieldwork

Prior research found that mineral dust contains significant quantities of phosphorus, a key growth factor for many species of dark-colored algae. Because dark-colored algae infiltrate snow and glaciers, decreasing their albedo and forcing them to absorb more sunshine, understanding the mechanics of dust delivery is imperative for accurately measuring glacial melt and estimating the impact of ongoing climate change.

“Most climate models omit this high-latitude dust,” said Kok.

To better understand how mineral dust affects the Greenland Ice Sheet, researchers captured aerosols and took measurements from ice cores and snow samples at a location north of Kangerlussuaq in southwest Greenland.

“To my knowledge, this is the first study to conduct real-time aerosol measurements on the Greenland Ice Sheet and connect those results to the algal blooms forming on the ice.”

“We were in a tent camp approximately 35 to 100 kilometers into the Greenland Ice Sheet,” said Liane Benning, a biogeochemist at the GFZ Helmholtz Centre for Geosciences in Germany and coauthor of the study. “We were there for up to 5 to 6 weeks to get these samples.”

The collected materials enabled the researchers to scrutinize dust above and within the glacier, which would, in turn, allow them to determine the dust’s origin, composition, and how many algae it could feed.

Scanning electron microscopes revealed the aerosols were primarily composed of mineral dust from the southern end of the Greenland Ice Sheet, which aligns with past research showing that area is a great producer of dust emissions. The quantity within the aerosols suggests the dust contains enough phosphorus to fuel massive algal blooms within the ice sheet.

“To my knowledge this is the first study to conduct real-time aerosol measurements on the Greenland Ice Sheet and connect those results to the algal blooms forming on the ice,” said Jenine McCutcheon, a geomicrobiologist at the University of Waterloo in Canada and lead author of the study. “Local Greenlandic locations near the coast are the most likely source, which matches our geochemical analyses.”

Microbes on the Move

But the results also revealed something else. In addition to mineral dust, the aerosols contained soot, fungi, and different species of algae specialized to living in ice and snow. The researchers detected one species of glacial ice algae, Ancylonema nordenskioeldii, that is well-known to reduce glacial albedo and increase melting.

The study suggests ice-melting microbes may be blown across the ice sheet, allowing them to penetrate areas previously unexposed to microbes. “These organisms can be picked up by wind,” explained McCutcheon, “which may provide a means for these algae to be transported to new locations on the ice.”

New research finds that phosphorus (P), along with other minerals, is transported to the Greenland Ice Sheet from bare soil downwind. Credit: McCutcheon et al., 2026, https://doi.org/10.1021/acs.est.5c13873, CC BY 4.0

Because other high-latitude environments are similarly pilloried by nutrient-rich dust, the study has wider implications for the Arctic, said Kok. “This study underscores the need to include this dust for more accurate predictions of how the Greenland Ice Sheet, and the Arctic more broadly, will evolve in the future.”

McCutcheon agreed. “While these results won’t stop ice mass loss, they will help us better understand how melting will progress in the future,” she said.

—Taylor Mitchell Brown (@tmitchellbrown.bsky.social), Science Writer

Citation: Brown, T. M. (2026), Greenland dust delivers nutrients to ice-melting algae, Eos, 107, https://doi.org/10.1029/2026EO260069. Published on 27 February 2026. Text © 2026. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

More than 2 billion people live within 50 kilometers of a coastline and are extremely vulnerable to climate hazards such as excessive rainfall and flooding.

A new study in Nature Communications shows how marine heat waves can worsen excess rainfall in coastal areas, potentially exacerbating flooding and its associated losses, including of human lives. Researchers found that from 1982 to 2022, between 5% and 25% of extreme rainfall events in coastal areas occurred downwind of nearby marine heat waves. Compared to events that weren’t downwind of marine heat waves, these rainfall events saw about 20%–30% more rain on average, as well as a 30% increase in fatalities.

“This is a serious concern because marine heatwaves not only intensify general rainfall but also exacerbate extreme rainfall events,” said Zhengguang Zhang, corresponding author of the new study and a climate scientist at the Ocean University of China in Qingdao, via email. Marine heat waves are happening more often and lasting longer, increasing the possibility that coastal rainfall and weather may be affected even more dramatically as the climate changes.

New Insights from Existing Data

In the study, the researchers define marine heat waves as those occurring when the sea surface temperature of an area exceeds 90% of the average value recorded over several decades for a period longer than 5 days. These heat waves can devastate marine ecosystems, and the ecological damage can have knock-on effects, causing massive losses to people and economies that depend on the ocean.

“This study beautifully reframes existing information [such as satellite data] in the context of marine heat waves and shows that coastal rainfall can clearly be impacted by these heat waves.”

The researchers combed through various long-term satellite and climate databases, such as NOAA’s Optimum Interpolation Sea Surface Temperature dataset, to build global maps of sea surface temperatures. They used these sea surface temperature maps to locate marine heat waves and linked them to excessive rainfall events in land areas as far as hundreds of kilometers downwind.

“This study beautifully reframes existing information in the context of marine heat waves and shows that coastal rainfall can clearly be impacted by these heat waves,” said Alex Sen Gupta, a climate scientist at the University of New South Wales in Sydney, Australia, who was not involved in the study.

From Hot Water to Excess Rain

Marine heat waves can vary widely in both their temperature and spatial extent, ranging from roughly 100,000 square kilometers—about the size of Iceland—to several million square kilometers or more. To compare heat waves with such different sizes, shapes, and characteristics, the researchers turned to mathematics.

“Marine heatwaves are characterized by a warm core with temperatures decreasing gradually outward, and Gaussian functions (a common mathematical tool) are often used to describe this kind of heat diffusion,” said Zhang. Using a Gaussian fit allowed the researchers to summarize and extract robust measures of scale and temperature gradients from noisy observational data and compare many marine heat waves and their effects on wind and rainfall.

“We found that marine heatwaves have the ability to influence the atmosphere above them and enhance rainfall downwind,” Zhang said. Areas downwind of marine heat waves experienced more frequent and more intense extreme rainfall, which the study defined as rain events that ranked among the wettest 1% of all rainy days in a particular land area. These extreme rain events peaked within the radius of the heat wave, which could sometimes stretch for hundreds of kilometers, and usually within 1–3 days of the heat wave forming.

The study analyses also yielded clues about how marine heat waves may be causing excess rain in downwind areas. The warm waters of a marine heat wave force the air above to mix violently, increasing atmospheric turbulence and strengthening winds. As these warm, wet winds move through and away from the marine heat wave, they collide with existing air and are forced upward, carrying their extra moisture with them. The rising, moisture-rich air then produces heavy rainfall, often over land downwind of the marine heat waves.

Connections Made, but Uncertainties Remain

Though the study clearly connects marine heat waves and downwind precipitation, the precise physical pathways involved may be more varied than they first appear, according to Sen Gupta.

“I don’t think the analysis necessarily distinguishes between different mechanisms as to how marine heat waves are impacting extreme rainfall events on land,” he said. For example, Sen Gupta noted that the study emphasized the importance of temperature gradients within marine heat waves as a key driver of rainfall downwind. “But temperature maximums within the heat waves may influence downwind rainfall just as much as temperature gradients.”

“Almost all the marine heatwave-related flood events that killed over a hundred people occurred in developing countries.”

Although the study builds a connection between marine heat waves and extreme rainfall, it does not establish a causal link between the heat waves and floods. “Establishing a direct connection is highly challenging due to the complexity of flooding, which is influenced by a lot of factors including topography, surface runoff, and even groundwater,” Zhang said. However, 10%–30% of flood events during the period covered in the study occurred downwind of a marine heat wave.

“Also, what we do not show in the paper is that, almost all the marine heatwave-related flood events that killed over a hundred people occurred in developing countries,” said Zhang. “Coastal communities, especially in developing countries, should incorporate marine conditions into their forecasts of extreme events, which may allow for a more accurate assessment of the severity of extreme rainfall or floods.”

—Adityarup Chakravorty (chakravo@gmail.com), Science Writer

Citation: Chakravorty, A. (2026), Marine heat waves can increase coastal rainfall, Eos, 107, https://doi.org/10.1029/2026EO260068. Published on 27 February 2026. Text © 2026. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: AGU Advances

In January 2025, a series of devastating wildfires swept through Los Angeles, causing widespread and catastrophic damage to critical infrastructure, displacing entire communities, and inflicting severe harm on the surrounding environment.

Landsat image of the Eaton fire on 14 January 2025. Brown and red colors display burned areas. Credit: Li et al. [2026], Figure 1e

By leveraging fire and emissions observations from remote satellites, Li et al. [2026] document the fire spread thus revealing how the fire moved after ignition and reached the urban settlements. In particular, the timing of the fire spread provides innovative information and supports the development of management strategies to cope with analogous future events. Interestingly, the authors found that residential fires released less carbon monoxide (CO) emissions per unit of radiative energy with respect to vegetation fires. The authors conclude that the observed dynamics of fire emissions and their linkage to fire intensity by new satellites open new opportunities to improve air quality forecasting.  

Citation: Li, F., Zhang, X., Cochrane, M., Kondragunta, S., & An, S. (2026). Fire spread, intensity, and emissions observations by multiple satellites: The southern California wildfires of January 2025. AGU Advances, 7, e2025AV002064. https://doi.org/10.1029/2025AV002064

—Alberto Montanari, Editor-in-Chief, AGU Advances

Text © 2026. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

Heavy rainfall in the Zona da Mata area of Brazil has triggered multiple landslides. Over 50 people have been killed.

Over the period of 23 and 24 February 2026, extremely intense rainfall struck the Zona da Mata area of Minas Gerais (MG), Brazil, triggering landslides and flooding. The most seriously affected area was the city of Juiz de Fora, but Uba also suffered extensive flooding.

It is clear that the majority of fatalities occurred as a consequence of landslides, although the mainstream media persists in describing the event as flooding. Reports suggest that 54 people have been killed with a further 14 still missing.

Poder360 has posted some drone footage of the aftermath of this disaster to Youtube:-

This footage includes two damaging landslide sites. This is the first:-

The aftermath of one of the landslides triggered by the 23 – 24 February 2026 rainfall event in Juiz de Fora, Brazil. Still from a video captured by Viory and posted to Youtube by Poder360.

There are three landslides here, all in close proximity. The crown of the landslides appears to be in less steep, deforested terrain. The landslides appear to be in deeply weathered soil, and they are shallow in nature. The proximity of the houses to the foot of the slope is notable – and there are many other houses built on the slope.

The second site is somewhat different:-

The aftermath of another of the landslides triggered by the 23 – 24 February 2026 rainfall event in Juiz da Fore, Brazil. Still from a video captured by Viory and posted to Youtube by Poder360.

In this case, it appears that a flow down a gully on the upper slope has expanded onto the lower slope, entraining a large amount of material to form a significant landslide. Again, the landslide appears to involve a considerable volume of weathered material.

Judging by media images, there are many more landslides across the city.

That there is a high level of landslide risk in Juiz de Fora is well established. Indeed, in 2021 the Geological Survey of Brazil (CPRM) published a report (in Portugese) whose translated title is “Diagnosis of the population in areas of geological risk,  Juiz de Fora“. This identified 304 locations of high or very high landslide risk, comprising 16,436 households.

Given that the rainfall on 23-24 February 2026 was at a record level, the disaster was all but inevitable.

Reference

Lana, J.C and Marcussi, M.C.R. 2021. “Diagnóstico da população em áreas de risco geológico, Juiz de Fora, MG”. Publicação do Serviço Geológico do Brasil – CPRM. 15 pp.

Return to The Landslide Blog homepage Text © 2026. The authors. CC BY-NC-ND 3.0
Except where otherwise noted, images are subject to copyright. Any reuse without express permission from the copyright owner is prohibited.

SummaryAccurate earthquake hypocentres are fundamental to a wide range of geophysical studies, yet source depth remains poorly constrained in teleseismic earthquake catalogues. Near source surface reflections such as pP, sP, and sS (known as depth phases) provide critical information for resolving hypocentral depth, particularly for intermediate-depth earthquakes. The number of depth phases reported by global earthquake monitoring agencies has declined significantly in recent decades, potentially reducing the precision of resolved earthquake depths. To address this, we automatically detect P, pP, sP, S and sS phase arrivals using teleseismic ad-hoc arrays. We detect these phases for earthquakes in the South American Subduction Zone (SASZ) at depths of 40–350 km and between mb 4.7 to 6.5. The identified phases are integrated with the phases reported to the ISC Bulletin, and used to relocate earthquakes with ISCloc. We assess the impact of incorporating automatically detected, ad-hoc array-derived depth phases on earthquake relocations across the SASZ, and find an improvement in depth resolution for 88.8% of earthquakes. Using this enhanced catalogue we investigate the structure of the Wadati-Benioff zone, focusing on two significant earthquakes: the 2005 Mw 7.7 Tarapacá and 2019 Mw 8.0 Peru events. Finally, we successfully apply our methodology to deep focus earthquakes (350-700 km), which further define the deepest portion of the seismogenic slab. Our results demonstrate the potential for automatically detected, ad-hoc array-derived depth phases to substantially improve the accuracy of teleseismic earthquake hypocentres, and offer further constraint upon slab geometry and seismogenic structure.

SummaryThis study aims to retrieve P waves from seismic ambient noise recorded by a dense local broadband network at the Chémery underground gas storage site, where anticline deformation was previously identified through wells and seismic reflection survey. To this end, we propose a new approach for reconstructing P waves from ambient noise. We process the passive seismic data to reconstruct the body wave component of the empirical Green’s functions (EGF). The retrieved P-wave arrivals were identified and analyzed, revealing that in this dataset, the picked arrival times likely correspond to non-physical head waves rather than direct or diving P-wave arrivals between virtual sources and receivers. Numerical simulations support this idea of non-unique interpretation of the passively reconstructed P-wave arrivals. The simulations suggest the potential for mapping lateral heterogeneities above the critical refractor as a cumulative time-delay, although for this dataset the anticline-induced time-delay is likely within the measurement uncertainties. It is found that the dominance of non-physical head waves over diving waves is primarily due to the large distance from the network to ambient noise sources.

SummaryOceanic subduction zone is the dominant pathway for transporting carbon into the interior of the Earth, and thus plays a critical role in deep carbon cycling. Despite being recognized as a key mechanism for carbon release in subduction zones, the metamorphic decarbonation outflux and efficiency remain subjects of ongoing debate. The thermal structure of subduction zone is widely recognized as a primary dynamic control on metamorphic decarbonation, however, the quantitative relationship between metamorphic carbon outflux and simplified thermal parameters of subduction zones (here defined as φ= slab age × subduction velocity/100 in kilometer) remains poorly constrained. On the other hand, previous studies on metamorphic decarbonation have been conducted within two distinct scenarios: the P-T-dependent decarbonation (PTD) system versus P-T-H2O-dependent decarbonation (PTHD) system, yet a quantitative comparison between these two scenarios remains lacking. In order to investigate the metamorphic decarbonation behavior of subducting slab in the PTD versus PTHD systems, we develop a coupled thermo-petrological model by integrating the thermodynamic dataset of temperature-pressure-(H2O)-dependent CO2 content into the thermal model of subduction zones. Systematic numerical models indicate that the metamorphic carbon outflux in the PTHD system is about 50 per cent lower than that predicted in the PTD system. Meanwhile, the quantitative functional relationship has been built between the metamorphic carbon outflux and φ, which reveals that the decarbonation outflux and efficiency decrease exponentially with increasing φ in both systems. Under present-day widespread subduction thermal conditions with the φ values of around 30 km, both PTD and PTHD system models yield low metamorphic decarbonation efficiency, suggesting that a substantial proportion of slab carbon is likely retained in the slab and transported into the deeper mantle.

Publication date: Available online 26 February 2026

Source: Advances in Space Research

Author(s): Mehrdad Mohseni, Iman Mohammadzaman