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Algae in the ocean can pose a significant risk to humans, marine life, and the seafood industry. Under favorable conditions for algae growth, certain algae species can multiply rapidly, a phenomenon known as algal blooms. Although algae always release small amounts of toxins, a massive increase in algae numbers leads to a high concentration of toxins in the water. These toxins can accumulate in marine organisms, such as mussels.

Humans have been reshaping the environment for at least 10,000 years. But the Anthropocene is the name given to the specific period of Earth history during which humans have had a global effect on the planet's climate and ecosystems. Despite formal rejection as a geological epoch, it's widely understood within academic research as useful shorthand for the age of human interference in the Earth system.

Earth's cloud cover is rapidly shrinking and contributing to record-breaking temperatures, according to new research involving the Monash-led Australian Research Council Center of Excellence for 21st Century Weather.

Intense, short-lived summer downpours are expected to become both more frequent and more intense across Alpine regions as the climate warms. In a new study, scientists from the University of Lausanne (UNIL) and the University of Padova analyzed data from nearly 300 mountain weather stations and found that a 2°C rise in regional temperature could double the frequency of these extreme events.

Scientists used satellite data, drones and on-the-ground observations to assess the edges of existing peatlands (waterlogged ecosystems that store vast amounts of carbon). The study—led by the University of Exeter—found peatlands in the European and Canadian Arctic have expanded outwards in the last 40 years.

A community in China had a narrow escape when a landslide, triggered by Typhoon Wutip, occurred on the slopes above the village. Fortunately, the population had been evacuated when a local woman noted signs that a failure might be imminent.

At about 4 am on 15 June 2025, rainfall associated with the remnants of Typhoon Wutip triggered a landslide at Zhonghe village in western Guangdong province in China. At present I am unable to give a precise location for this event, which is listed in the Chinese media as having occurred at Lian’er Natural Village, Zhonghe village, located in Guizi Town, Xinyi City, Maoming. Guizi town is located at [22.6397, 111.1113], so it is in this general area.

China Daily has a photographic feature on this landslide, which includes this image:-

The 15 June 2025 landslide at Zhonghe village in western Guangdong province, China. Image via China Daily.

There is also a view from the crown of the failure looking along the landslide track:-

View from the crown of the 15 June 2025 landslide at Zhonghe village in western Guangdong province, China. Image via China Daily.

This failure affected 25 households and 57 people, but all were evacuated in the hours prior to the event (see below). The landslide itself appears to have been a large, shallow failure that has channelised before striking the village. Note also at least two other shallow failures in the same area – these landslides are characteristic of landslides triggered by very high rainfall intensities that drive saturation and a loss of suction forces.

It is fortunate that the material involved in the failure was comparatively fine-grained, which has meant that the damage to the village appears to be modest. XKB has this image of the aftermath of the landslide:-

The aftermath of the 15 June 2025 landslide at Zhonghe village in western Guangdong province, China. Image via XKB.

There is an article in nfnews (in Mandarin) that describes the sequence of events that led to the evacuation of the community. The key person is Liu Mingfang, a member of the Zhonghe Village Committee. This is a description of the events (using Google Translate):-

In the rain, her vision was blurred, and Liu Mingfang used a flashlight to patrol along the muddy village road. At 0:42 on the 15th, she suddenly discovered: “Why is this water yellow and muddy, and it still carries sediment?”

Red flags! She immediately dialed the phone number of Cao Musheng, the village party secretary: “Secretary, there is an abnormality in the water, something may happen!” ”

In less than 5 minutes, Liu Chunhua and Cao Musheng, deputy mayors of the village, arrived at the scene. After research and judgment, Liu Chunhua decisively reported to the town’s three prevention offices and received instructions: transfer immediately!

At 0:58, a total of 10 village cadres and village cadres rushed from all directions to the entrance of Lian’er Natural Village. Immediately afterwards, the sound of gongs, knocks on the door, and shouts instantly tore apart the rainy night.

The entire community was relocated before the slope failed.

Return to The Landslide Blog homepage Text © 2023. 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.

SummaryFor the inversion of crustal deformation data, where both the fault geometry and slip distribution need to be estimated, attempts have been made to estimate them simultaneously within the framework of Bayesian inference. In these methods, an analytic expression for the posterior distribution of the parameters cannot be obtained depending on the settings of the probability distribution. The Monte Carlo method is often used to approximate the probability distribution by several samples. However, Monte Carlo sampling becomes computationally expensive as the dimensionality of the parameters increases, making it challenging to apply these methods to inverse analyses targeting large-scale earthquakes with complex rupture patterns, where the parameters to be estimated are high-dimensional. In this study, we developed an efficient algorithm for the simultaneous Bayesian estimation of fault geometry and slip distribution that is robust against high-dimensional parameters, facilitating the estimation of multi-segment fault geometry and complex slip distribution. When comparing the developed method with a conventional method in a numerical experiment where the parameters were high dimensional, it was confirmed that the accuracy and convergence of the estimation results were improved while reducing computational costs. As an application example of the developed method, we estimated fault geometry and slip distribution from the crustal deformation observed during the 2024 Noto Peninsula earthquake, considering models with one-, two-, and three-fault segments. By comparing the results, we demonstrated that the three-segment model is the most plausible, emphasising the importance of improving the estimation methods to accurately estimate multi-segment fault geometry with a complex slip distribution.

SummaryThe characterization of submarine volcanism associated with extension along continental margins is essential for understanding the evolution of rifting basins. In the Okinawa Trough, between the Eurasian continent and the Ryukyu Arc, submarine volcanism remains poorly understood. Here, we conducted detailed magnetic and gravity surveys aboard research vessels off Kume Island in the mid-Okinawa Trough to clarify the distribution of different types of submarine volcanic activities. Equivalent magnetization intensities were estimated from observed magnetic anomalies, and Bouguer gravity anomalies, calculated from the obtained free-air gravity anomalies, were used to estimate crustal thickness. Differences in crustal equivalent magnetization, Bouguer gravity anomaly, and crustal thickness among bathymetric highs allowed us to identify four distinct groups of submarine volcanic edifices reflecting the evolution of rifting. Edifices of Group 1 are affected by basaltic magma intrusions associated with back-arc extension. Those of Group 2 have moderate equivalent magnetizations and Bouguer gravity anomalies compared to other edifices in the study area; the equivalent magnetization intensity in this group is comparable to the average intensity of the oceanic lithosphere. Edifices of Group 3 may have been affected by additional, voluminous magma supplies from active island arc magma sources. Finally, those of Group 4 are characterized by fewer basaltic intrusions compared to other groups and a lower degree of crustal thinning associated with back-arc extension. Moreover, the faults and fractures formed during the development of the Kerama Gap may have affected volcanism in our study area.

AbstractMacroseismic intensity classifies the ground shaking at a locality by comparing the observed effects on humans and buildings with the scenarios characterising each intensity degree according to a macroseismic scale. This practice may involve uncertainty in assessing intensity degree due to several factors. These uncertainties propagate to subsequent elaborations, such as the parameters of pre-instrumental earthquakes determined from macroseismic data. In Italy, more than 60 per cent of the earthquakes in CPTI15, the Italian Parametric Earthquake Catalogue covering the period 1000–2020, rely on intensity data collected in DBMI15, the Italian Macroseismic Database. Their parameters are estimated with the ‘Boxer’ software, which determines the location and magnitude starting from their macroseismic intensity distributions. In this work, we explore the potential impact of possible inaccurate intensity assessments at a single site on macroseismic parameters (i.e. locations and magnitudes) of Italian earthquakes. We select 1108 earthquakes with at least 10 intensity data points from CPTI15 that occurred in the period 1279–2020. For each event, we simulate more than 100 sets of intensity distributions, for a total of 138.327 simulations, by varying the intensities at the sites of ± 1 with a half-degree step starting from the intensity of DBMI15. Each simulated distribution is then parameterised using the same approach adopted by CPTI15 (i.e. Boxer), and the results are compared with the macroseismic epicentre and magnitude of CPTI15. The resulting parameters from all the simulated distributions are coherent with those provided by CPTI15. Locations estimates are within 5 km from CPTI15’s for 55 per cent of the cases, and within 10 km for 83 per cent. The magnitudes of 68 per cent of simulations are within ± 0.2 units of difference from the CPTI15 magnitudes and 87 per cent within ± 0.3 units, similar to the statistical error of instrumental magnitude estimation. Moreover, we treat uncertain intensity values (i.e. 6–7) as equally representative of either the lowest intensity level (i.e. 6–7 as 6) and the highest intensity level (i.e. 6–7 as 7), and we analyse their impact on the parameters. The differences with the CPTI15 magnitude are not significant for either analysis, with more than 97.7 per cent of the earthquakes falling within ± 0.3 units of difference.

The central estimate of the remaining carbon budget for 1.5°C is 130 billion tons of carbon dioxide (CO2) (from the beginning of 2025). This would be exhausted in a little more than three years at current levels of CO2 emissions, according to the latest Indicators of Global Climate Change study published in the journal Earth System Science Data, and the budget for 1.6°C or 1.7°C could be exceeded within nine years.

An international team of geoscientists, chemists and climate scientists, has found evidence of a possible ghost plume beneath the territory of Oman. In their paper published in the journal Earth and Planetary Science Letters, the group describes the different types of evidence for the plume they found and what it could mean for the study of plate tectonics.

Submarine canyons around Antarctica tend to have less sea ice, higher sea surface temperatures, and more biomass such as phytoplankton blooms than the shelves they cut into. Phytoplankton blooms feed Antarctic krill, making these canyons an attractive feeding ground for larger predators such as penguins, who make permanent homes for foraging and breeding on the shores surrounding submarine canyons.

During the last ice age, storms soaked the now-arid Southwestern U.S., while today's rainy Pacific Northwest remained relatively dry. As global temperatures rose and ice sheets retreated, those storms shifted north—reshaping the climate patterns that define both regions today.

Boreal peatlands in Canada provide crucial ecosystem services, from flood mitigation and water purification to storing colossal amounts of carbon and providing a habitat for species such as caribou.

Over the past several decades, more than 36,000 hectares of well pads have been constructed to house oil and gas drilling platforms in these landscapes, destroying the underlying vegetation and disrupting the flow of water through the ground.

“We want to get as close to the original state as is possible and realistic.”

Once drilling operations are finished, operators are required to return pads to a state similar to that before construction. Though restoration efforts have historically focused on tree planting, reintroducing the right mosses is crucial for restoring functional peatlands. A study in Ecological Engineering outlines a new approach to reintroduce these keystone plant species, tested for the first time at the scale of a full well pad in Alberta, Canada.

“We want to get as close to the original state as is possible and realistic, given the very long time scales that peatlands develop over,” said Murdoch McKinnon, a graduate student at the University of Waterloo and lead author of the study.

The challenge is providing the right hydrological conditions for mosses to thrive.

Removing Fill

Well pads are constructed by heaping crushed mineral fill onto a section of peat to create a harder level surface.

Traditionally, researchers in the region have reintroduced moss by first completely removing the fill, which lowers the surface so that it is closer to the water table. In some cases, they would bury some of the fill under the newly exposed peat, a technique referred to as inversion.

This process has been successful in establishing the Sphagnum mosses typical of bogs, which have acidic soil that is low in nutrients. It’s been less successful in reintroducing the Bryopsida mosses characteristic of fens, the nutrient-rich wetlands that make up almost two thirds of peatlands in Canada’s Western Boreal Plain.

“I think it’s a good approach, but maybe the surface of the pad was not low enough to have flowing water, which you need in a fen.”

To reestablish a moss community that could eventually turn into a fen, the team left some of the fill on the surface, which provided the minerals that Bryopsida mosses rely on for growth. The team then roughed up the surface with an excavator to create different microsites, which promotes species diversity.

After introducing mosses from a nearby donor fen and closely monitoring the site for two growing seasons, researchers found that conditions for the reestablishment of Bryopsida mosses were best when the water table was within 6 centimeters (2 inches) of the surface. That was often the case along the edges of the pad that received water from the adjacent peatland, whereas the mosses in the interior of the pad struggled with drier conditions.

“I think it’s a good approach, but maybe the surface of the pad was not low enough to have flowing water, which you need in a fen,” said Line Rochefort, an expert in peatland restoration at Université Laval in Quebec who was not involved in the study.

“Without addressing that, it’s hard to introduce and establish peatland vegetation on mineral substrate,” said Bin Xu, a peatland ecologist at the Northern Alberta Institute of Technology (NAIT) who worked on the project. “On the flip side, when you do have good hydrobiological conditions, it’s really easy to support peat-forming vegetation, which is encouraging.”

A well pad located near the town of Slave Lake, Alberta, was still brown immediately after researchers introduced the moss, before it started to become established. Credit: University of Waterloo

An important takeaway from the study is the importance of decompacting the surface by roughing it up to allow for not only hydrological flow across the pad but also the natural vertical fluctuation of the water table, Xu said.

He and colleagues at NAIT have now applied these lessons to three additional well pads in Alberta, and industry experts have used a similar approach on around a dozen more, Xu said. “Through informing policy and sharing the learnings with industry, we can together address the need to reclaim well pads built in peatland across the province.”

—Kaja Šeruga, Science Writer

Citation: Šeruga, K. (2025), Surface conditions affect how mosses take to former well pads in Canada’s boreal fens, Eos, 106, https://doi.org/10.1029/2025EO250227. Published on 18 June 2025. Text © 2025. 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.

Source: Journal of Geophysical Research: Oceans

Submarine canyons around Antarctica tend to have less sea ice, higher sea surface temperatures, and more biomass such as phytoplankton blooms than the shelves they cut into. Phytoplankton blooms feed Antarctic krill, making these canyons an attractive feeding ground for larger predators such as penguins, who make permanent homes for foraging and breeding on the shores surrounding submarine canyons.

Previous studies suggested that, as on a farm, the phytoplankton blooms that attract predators were locally grown, supported by the upwelling of nutrient-rich water. But newer research shows that water moves through the canyon more quickly than phytoplankton can accumulate, so it is likely that currents transport most of the surface biomass into the canyon from other parts of the ocean. Canyons therefore act more like biomass supermarkets, to which food is delivered, than like farms.

McKee et al. examined to what degree phytoplankton grow locally in Palmer Deep canyon on the western Antarctic Peninsula versus being transported in by ocean currents. To do so, they used high-frequency radar to measure ocean currents and satellite imagery taken hours to days apart to measure levels of surface chlorophyll, a proxy for phytoplankton.

The results showed that both processes were occurring. Ocean currents appeared to bring in much of the phytoplankton that flowed on the western side of the canyon, making it more like a supermarket, the researchers write. In contrast, more phytoplankton seem to be growing in place on the eastern flank, making it more like a farm.

The authors also examined how the movement of water correlated to plankton growth, by tracking chlorophyll levels in moving parcels of water. In general, they found that water parcels that saw an increase in phytoplankton levels as they moved through the canyon tended to exhibit more clockwise motion, whereas parcels that saw decreasing phytoplankton levels showed more counterclockwise rotation. (Journal of Geophysical Research: Oceans, https://doi.org/10.1029/2024JC022101, 2025)

—Rebecca Owen (@beccapox.bsky.social), Science Writer

Citation: Owen, R. (2025), Where do Antarctic submarine canyons get their marine life?, Eos, 106, https://doi.org/10.1029/2025EO250224. Published on 18 June 2025. Text © 2025. AGU. 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.

A new tool that assesses the level of danger posed by tsunamis in real-time has been made operational on a global scale.

New research reveals the importance of winter sea ice in the year-to-year variability of the amount of atmospheric CO2 absorbed by a region of the Southern Ocean.

In a study published in Weather, researchers estimated the current chances and characteristics of extreme hot episodes in the UK, and how they have changed over the last six decades.

Derek Cronmiller of the Yukon Geological Survey has provided a stunning set of the images of the fascinating recent failure that partially blocked the Yukon River.

Following my post yesterday about the May 2025 landslide on the Yukon River, Derek Cronmiller, who is head of Surficial Geology at the Yukon Geological Survey kindly made contact to provide further information about this most interesting failure. He has also provided an amazing set of images of the landslide.

Derek noted the following about the landslide:-

“The slide is a 9 km above Lake Laberge and happed sometime between May 14th and 18th as constrained by Sentinel imagery and river user reports.“

“The slide is 950 m wide and up to 250m long from crown to toe. It blocked ~ 45% of the active channel which is no small feat on the Yukon River! The material is finely bedded glaciolacustrine silt and clay at river level (and below) grading up to massive medium to coarse sand at the top of the main scarp with variable thickness of aeolian dune cover at the surface.  Perhaps the most interesting part of the slide is that the rupture surface daylighted somewhere in the river and thrust river bottom sediments (and vegetation) several metres above the river level. There are some great spreading structures on the slide reminiscent of sensitive clay slides in Quebec. We observed seeps daylighting at the bottom of the adjacent slopes just above river level at the transition from sands to silt and clay. Slides have occurred here in the past but an order of magnitude smaller.”

And so to the images. This image shows the landslide from a drone, looking from the crown towards the river:-

The May 2025 Yukon River landslide, viewed from a drone. Image copyright the Yukon Geological Survey, used with permission.

The very beautiful morphology of this landslide is visible with rows of back-tilted trees, with upright trees in between. Note also the uplifted toe of the landslide, including river gravels.

Let’s take a look at the toe – here is the uplifted portion, located almost half way across the former channel. The scale of the uplift here is really impressive:-

The uplifted toe of the May 2025 Yukon River landslide. Image copyright the Yukon Geological Survey, used with permission.

For those who are unfamilar with rational landslides, and who may be wondering how this is possible, I provided a sketch of this mechanism back in 2013 at the time of the Hatfield Stainforth landslide:-

Sketch of the rotational landslide mechanism of the 2013 Hatfield Stainforth landslide. The Yukon River landslide had a similar mechanism.

This rotational generates some complex structures in the landslide, including horst and graben phenomenon:-

Horst and graben structures in the toe of the May 2025 Yukon River landslide. Image copyright the Yukon Geological Survey, used with permission.

And this image shows the uplifted river gravels in more detail:-

Uplifted river gravels in the toe of the May 2025 Yukon River landslide. Image copyright the Yukon Geological Survey, used with permission.

Moving up into the main body of the landslide, there are some extremely impressive back-tilted blocks:-

Back-tilted blocks in the May 2025 Yukon River landslide. Image copyright the Yukon Geological Survey, used with permission.

And also some horst and graben structures:-

Back-tilted trees in the May 2025 Yukon River landslide. Image copyright the Yukon Geological Survey, used with permission.

Finally, there are areas of seepage as Derek noted above, which probably gives an indication of one of the drivers of this landslide:-

Seepage in the May 2025 Yukon River landslide. Image copyright the Yukon Geological Survey, used with permission.

This is a really interesting landslide – in many ways, a textbook example of a complex rotational failure. If I was still teaching, I would use this landslide to illustrate the mechanisms of rotational landslides.

Many thanks to Derek Cronmiller and his colleagues at the Yukon Geological Survey for providing these amazing images and the detailed commentary. I hope that they will write the landslide up for publication in due course.

Return to The Landslide Blog homepage Text © 2023. 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.

AbstractHigh-precision geoid models have traditionally been static, neglecting temporal variations. However, achieving geoid accuracy within 1-2 cm and maintaining dynamic height reference frames necessitates consideration of geoid spatiotemporal variations. GRACE/GRACE-FO and surface mass loading models provide means to estimate geoid changes, but their accuracy and reliability require further validation. This study proposes a method for dynamically maintaining regional height reference frames by integrating GNSS reference stations as core nodes and incorporating time-varying geoid data. This method dynamically corrects station heights by computing normal height variations using GNSS observations and geoid changes. Experiments conducted in Beijing and Shandong derived geoid changes using GRACE/GRACE-FO and surface mass loading, validated against long-term GNSS observations and leveling surveys. Results show a strong correlation (R ≈ 0.9; NSE > 0.4) between geoid changes derived from GRACE and surface mass loading, although amplitude discrepancies of up to 4 mm existed. In 41 experimental cases, accuracy improvement was observed in over 90 per cent of instances following geoid change corrections. In Beijing, 18 out of 26 results achieved accuracy improvements exceeding 20 per cent, five of which surpassed 90 per cent. In Shandong, 11 out of 15 results improved by over 10 per cent, including five exceeding 40 per cent. These findings confirm the feasibility and effectiveness of using GRACE/GRACE-FO and surface mass loading to estimate geoid changes. The proposed method significantly improves the accuracy of dynamic height reference frame maintenance, providing valuable insights for further refinement of geoid models.