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Australia has always had heat waves. But this week's heat wave in southeastern Australia is something else. Temperatures in some inland towns in South Australia, New South Wales and Victoria were up to 20°C above average for the time of year, which meteorologists described as "incredibly abnormal." Victoria's heat record toppled after Walpeup and Hopetoun hit 48.9°C. The heat is set to continue until Saturday in some areas.

This week, Victoria recorded its hottest day in nearly six years. On Jan. 27, the northwest towns of Walpeup and Hopetoun reached 48.9°C, and the temperature in parts of Melbourne soared over 45°C. Towns in South Australia also broke heat records.

Far from simply a source of unstructured online content, disaster management in the digital age can be supported by careful analysis of online social-media data, suggests a paper published in Natural Hazards and Earth System Sciences (NHESS) titled "Social Media for Managing Disasters Triggered by Natural Hazards: A Critical Review of Data Collection Strategies and Actionable Insights."

Author(s): Peng Wang, Yogeshwar Nath Mishra, Seth Pree, Lihong V. Wang, Dag Hanstorp, John P. Koulakis, Daniels Krimans, and Seth Putterman

Using a camera with 2-picosecond time resolution, researchers show that the atoms in a laser-induced plasma are more highly ionized than theory predicts.

[Phys. Rev. E 113, 015209] Published Fri Jan 30, 2026

SummaryGlobal Navigation Satellite System (GNSS) plays a fundamental role in monitoring time-dependent ground displacement. However, GNSS daily position time series can often contain significant outliers, reaching up to several centimeters. These are likely of non-tectonic origin, and, if not properly accounted for, they can significantly impact the accuracy and dependability of the estimation of key parameters for geophysical analyses, such as long-term velocities and transient deformations. Characterizing these outliers can provide information about their possible sources and help us implementing mitigation strategies. Asymmetric outliers, i.e., those characterized by a primary direction, therefore occurring on one side of the mean time series, are of particular interest since they could point to the presence of recurring or repeatable sources of error. Their key features and potential causes are, however, still not fully analyzed and understood. We analyze asymmetric outliers in thousands of GNSS time series across three regions – Central-Southern Italy, New Zealand, and the Western U.S. – using data from multiple processing centers, and we reveal some persistent features among all datasets. Tens of the analyzed sites exhibit hundreds of large outliers (10-50 mm), far exceeding typical position uncertainties (∼1-6 mm). Remarkably, the outliers are numerous in the horizontal component, and tend to occur near mountainous regions, with preferred direction roughly orthogonal to the local topography. The results consistency across different datasets and instrumental features suggest a physical origin for these outliers rather than a specific processing approach or instrumental configuration. Further analyses at local scales align with previous studies linking skewed position errors to uncorrected tropospheric delays driven by the coupling between atmospheric conditions and local terrain (e.g., trapped lee waves). However, other factors – such as multipath, snow accumulation on GNSS antennas or obstructed sky visibility – could also contribute to the observed asymmetric outliers. We explore mitigation strategies at both processing and post-processing stages, but further analyses and more sophisticated approaches, such as high-resolution tropospheric modeling, are needed to better understand the involved processes and achieve meaningful improvements.

SummaryThe Gravity Recovery and Climate Experiment (GRACE) and its Follow-On mission provide essential observations of Earth’s surface mass redistribution. However, inherent north-south striping noise in the GRACE spherical harmonic (SH) products limits their application at sub-basin scales. To address this, we introduce a novel spatial domain decorrelation filter, the Physical-Informed Spatial Pattern (PISP) filter, which leverages the structured physical characteristics of the noise for its precise identification and removal. Comprehensive numerical experiments validated that PISP effectively eliminates striping noise globally and yields a consistent noise background across latitudes, with noise reduced to a uniform level in more than 90% of the months examined and with stable performance under strong-noise conditions. In a case study of water storage variations in Lake Victoria, PISP preserves the primary signal amplitude and reduces the root-mean-square error relative to reference data to 5.84 cm after spatial smoothing, outperforming the 6.81 cm achieved by the MVMDS + DDK6. Furthermore, for three earthquakes with magnitudes exceeding 8.8, PISP effectively removes striping noise using regional masking, successfully recovering the co-seismic signal morphology. By further verifying the method’s stability across various noise scenarios, the results demonstrate PISP’s potential for future global research integrating multi-satellite gravity data.

SummarySlowslip events (SSEs) modulate the earthquake cycle in subduction zones, yet understanding their physics remains challenging due to sparse observations and high computational cost of physicsbased simulations. We present a scientific machine-learning approach using a data-driven reduced-order modelling (ROM) framework to efficiently simulate the SSE cycle governed by rate-and-state friction in a Cascadia-like 2D subduction setting. Our approach projects fault slip, sliprate, and state-variable trajectories onto a splinebased latent space, which is subsequently emulated using properorthogonal decomposition and radialbasisfunction interpolation. Achieving a speedup of ∼360, 000 × compared to volumetric simulations, the ROMs enable comprehensive parameter exploration and Bayesian Markov chain Monte Carlo (MCMC) inversion. By smoothly interpolating between the physics-based simulations, the ROMs reveal complex dependencies that might be overlooked with coarser parameter space sampling. Our analysis reveals complex, non-linear dependencies of SSE characteristics on the width and magnitude of the deep, low-effective-normal-stress region while holding frictional parameters constant. We show that, to first order, the recurrence time of SSEs is linearly dependent on the normalized fault width, defined as the SSE zone width divided by the characteristic nucleation length, in agreement with previous work. However, at second order, the recurrence interval can change more rapidly with small variations in the SSE zone width. We identify a region of steep, non-linear dependence of the recurrence interval on the normalized fault width, which we attribute to the extent of the velocity-weakening portion of the subduction interface that produces SSEs. Our MCMC inversion constrained by Northern Cascadia SSEs observations indicates near-lithostatic pore fluid pressure (99.6 ± 0.17% lithostatic) and positions the upper frictional transition zone at 30.4 ± 2.8 km depth, consistent with geophysical observations. The inversion resolves the deep SSE-portion of the slab spanning 45 ± 16 km with low effective normal stress of 3.8 ± 1.4 MPa. We discuss how varying the fault frictional parameters affects the MCMC-inverted parameter values. This framework provides a new tool for advancing the physics-based understanding of SSEs and subduction zone faulting mechanics. By systematically linking megathrust properties such as fluid pressure and fault strength to rate-and-state friction governed slow slip cycle characteristics, such as recurrence interval, our approach helps to constrain the first and second-order physics-based controls and the uncertainties of how subduction zones slip.

SummaryDuring the last glacial period, the Black Sea developed oxic bottom waters that generally preserved detrital titano-/magnetite, yet greigite (Fe₃S₄) occurs sporadically within nodules in these otherwise oxic sediments. To clarify their origin and significance, we combined rock magnetism, X-ray diffraction, and scanning electron microscopy with energy-dispersive X-ray spectroscopy on nodules from core MSM33-55-1 and screened fifteen nearby cores using the ratio of saturation isothermal remanent magnetization to low-field magnetic susceptibility (SIRM/κLF). SIRM/κLF thresholds were applied to classify samples as greigite-bearing and greigite-free, then the greigite-bearing sample proportion was calculated in 0.3-kyr bins from 70 to 20 ka. The nodules have S-rich interiors (elemental sulphur plus greigite) coated by Fe-hydroxide rims (goethite), indicating formation in localized sulphidic microenvironments embedded in otherwise oxic sediment. Palaeomagnetic comparisons indicate that greigite-bearing samples track greigite-free (detrital titano-/magnetite) records for relative palaeointensity (RPI) and inclination (zero lag for inclination; ∼0.5 kyr lag for RPI), which implies that greigite formed shortly after deposition and acquired an early-diagenetic chemical remanent magnetization near-synchronous with a detrital post-depositional remanent magnetization. Greigite-bearing sample proportion increases during interstadials with modest but significant positive correlations with total organic carbon (TOC) content (and TOC/κLF) and a negative correlation with κLF, consistent with enhanced organic-matter supply relative to detrital input promoting sulphidic microenvironments. Together, these results demonstrate that greigite-bearing nodules can be incorporated into palaeomagnetic reconstructions when carefully screened, and that they serve as markers of micro-scale sulphidisation coupled to conditions that favour organic-carbon retention in glacial Black Sea sediments.

Researchers at Concordia have developed a new method of measuring the amount of usable water stored in snowpacks. The comprehensive technique, known as snow water availability (SWA), uses satellite data and climate reanalysis techniques to calculate snow depth, snow density, and snow cover across a wide swath of Canada and Alaska.

Should growing glacial lakes be used for energy production and water supply—or remain protected as ecologically valuable systems? A research team from the University of Potsdam, together with partners from the University of Leeds, has recorded the distribution and volume of glacial lakes worldwide. Their findings allow various usage scenarios to be derived, particularly in areas where the largest glaciers still exist today. Their article has been published in Nature Water.

A new study led by climatologists at the University at Albany has found that extreme heat waves across the Caribbean are becoming significantly more frequent, longer and severe. This study examined extreme summer heat waves in the Caribbean over the last five decades, focusing on their causes and how they have changed over time.

Forecasting volcanic eruptions in time to alert authorities and populations remains a major global challenge. In a study published in Nature Communications, researchers and engineers from the Institut de Physique du Globe de Paris (IPGP) and the GFZ Helmholtz Centre for Geosciences present a new detection method, called "Jerk," using a single broadband seismometer. It is capable of identifying, in real time, very early precursor signals of volcanic eruptions generated by subtle ground movements associated with magma intrusions.

For decades, families in communities around Johannesburg have been living close to huge gold mining waste dumps. For many residents, the dust that is released there is just part of everyday life—but it can contain natural uranium compounds that come to the surface with the mined rock. A new study in the journal Environmental Geochemistry and Health reveals how this exposure is reflected in children's hair.

People living on the low-lying shores of the Bristol Channel and Severn estuary began their day like any other on January 30, 1607. The weather was calm. The sky was bright.

The King's Trough Complex is a several-hundred-kilometer-long, canyon-like system of trenches on the North Atlantic seafloor. Its formation was long thought to be the result of simple stretching of the oceanic crust. An international research team led by the GEOMAR Helmholtz Center for Ocean Research Kiel has now shown that the so-called "Grand Canyon of the Atlantic" was formed about 37 to 24 million years ago through the interplay of a temporarily existing plate boundary and an early branch of the Azores mantle plume. Their findings have been published in the journal Geochemistry, Geophysics, Geosystems.

To reduce air pollution associated with ocean transport, the International Maritime Organization tightened restrictions on sulfur content in ship fuel, resulting in an 80% reduction in emissions by 2020. That shift created an inadvertent real-world experiment in how man-made aerosols influence cloud formation over the ocean.

When most of us look out at the ocean, we see a mostly flat blue surface stretching to the horizon. It's easy to imagine the sea beneath as calm and largely static—a massive, still abyss far removed from everyday experience.

Wetlands make up only about 6% of the land area but contain about 30% of the terrestrial organic carbon pool. Therefore, CO2 emissions from wetlands are central to the global climate balance. In Denmark, the plan is to flood 140,000 hectares of low-lying land such as bogs and meadows as part of the Green Tripartite Agreement. Flooding such areas will slow down the decomposition of organic material in the soil and keep the CO2 in the soil rather than allowing it to be released to the atmosphere and contribute to the greenhouse effect. At least, that has been the rationale until now.

A new study suggests the world's oxygen-depleted seas may have a chance of returning to higher oxygen concentrations in the centuries to come, despite our increasingly warming climate.

The vital role apex predators play in maintaining healthy ecosystems is well-documented, but research published in Scientific Reports suggests predators might also influence the global carbon cycle. The study found that across coastal wetlands in the southeastern United States, soils store more carbon where American alligators are present, linking predator recovery to enhanced carbon retention in some of the planet’s most efficient natural carbon sinks.

Wetland carbon storage (so-called “blue carbon”) is facilitated by wetlands’ waterlogged, oxygen-poor soils, which slow decomposition and allow organic material to accumulate over time. Scientists know that when wetlands are drained or degraded, stored carbon can be released into the atmosphere as carbon dioxide. Less well understood is how biological interactions within these habitats shape carbon dynamics. The new study adds to a growing body of evidence showing that animals—particularly apex predators—can influence vegetation, soils, sediment flows, and nutrient cycles at scales large enough to affect the planet’s carbon budget.

“What we found was a positive correlation between alligator abundance and carbon sequestration in specific habitats,” said Christopher Murray, an ecologist at Southeastern Louisiana University and lead author of the study. “Where we have more alligators, from small populations to much larger populations, we actually see higher carbon sequestration.”

Across the alligator’s native range, wetlands stored an average of 0.16 gram more carbon per square centimeter in the top 10 centimeters of soil when alligators were present.

Murray and his colleagues at Southeastern and the Louisiana Universities Marine Consortium analyzed soil carbon data from the Smithsonian’s Coastal Carbon Network. From that database, the team selected 649 continuous soil cores from tidally influenced wetlands in 13 states. They compared those carbon measurements with data on alligator presence, density, and nesting patterns assembled from state wildlife agencies and long-running monitoring programs.

Across the alligator’s native range, wetlands stored an average of 0.16 gram more carbon per square centimeter in the top 10 centimeters of soil when alligators were present. That surface layer reflects relatively recent carbon accumulation over roughly the past 6 decades. This period overlaps with the recovery of alligator populations following the Endangered Species Protection Act of 1966.  

The researchers attribute the observed patterns to a combination of physical ecosystem engineering and trophic cascades, or actions by predators that reverberate through multiple layers of a food web. As apex predators, alligators may suppress herbivore populations that otherwise damage vegetation and disturb soils, potentially allowing denser plant growth and greater carbon burial. Alligators also modify wetland landscapes directly. By digging dens, carving channels, and creating small ponds, they reshape hydrology, redistribute sediments and nutrients, and create localized microhabitats where organic carbon can accumulate and persist.

Trophic Effects

At a continental scale—spanning a wide range of coastal wetland types across multiple states—the study found no statistically significant difference in carbon storage between sites with and without alligators. The authors suggest that this reflects substantial ecological variability across regions, including differences in vegetation, geomorphology, hydrology, and food web structure, which can mask the influence of any single predator species when ecosystems are analyzed collectively.

An American alligator rests on a fallen tree. Research suggests that wetlands within the alligator’s native range store more carbon in surface soils when alligators are present. Credit: Emil Siekkinen

“Originally, I was surprised by that finding,” said Murray. The team’s original hypothesis predicted higher carbon sequestration wherever alligators were present, consistent with trophic cascade theory. The absence of a clear continental-scale signal, Murray said, made it obvious to him, “later on, that there’s a different apex predator that is working in those habitats.”

When the analysis was narrowed to the alligator’s native range, thereby reducing ecological variability, the pattern became clearer. At these regional scales, wetlands with alligators consistently stored more carbon, suggesting that in ecosystems where they occupy the top trophic position, alligators may exert a detectable influence on wetland carbon dynamics.

“Apex predators like crocodilians have a critical role in the function of our world.”

 “This study is important because it links an apex predator directly to wetland soil carbon stocks, moving beyond theory to show that food web structure can shape carbon outcomes at ecosystem scales,” marine ecologist and Blue Carbon Lab director Peter Macreadie, who was not involved in the study, wrote in an email. “It also challenges prevailing blue carbon approaches by showing that long-term carbon storage depends not only on vegetation and sediments, but on maintaining intact trophic interactions.”

Such trophic effects help explain how sea otters maintain kelp forests by controlling sea urchins and why wolves have been linked to forest regeneration through changes in large herbivore behavior. The alligator study suggests that similar processes may operate in coastal wetlands, where predator presence supports vegetation growth, soil stability, and carbon retention.

The study does not establish causation, and Murray emphasized that long-term exclusion experiments would be needed to directly test how changes in alligator populations affect carbon accumulation over time. Even so, the findings suggest that predator recovery may have consequences for the climate that are rarely considered in conservation planning. Murray said that the implications of this work extend beyond carbon accounting, however. “Apex predators like crocodilians have a critical role in the function of our world,” he said. “And they should be respected rather than feared.”

—Emil Siekkinen, Science Writer

Citation: Siekkinen, E. (2026), Alligators may boost carbon storage in coastal wetlands, Eos, 107, https://doi.org/10.1029/2026EO260038. Published on 29 January 2026. Text © 2026. The authors. CC BY-NC-ND 3.0
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