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Extreme precipitation events are among the most damaging natural disasters and a major concern in our changing climate. In the U.S., since 1980, the most destructive events alone have caused more than 2,800 deaths and $700 billion in damages. But what is the total area of the country affected by these events each year? And how have these patterns changed over the past several decades? In a recent study in Geophysical Research Letters, led by researchers at Lamont-Doherty Earth Observatory, which is part of the Columbia Climate School, the authors discovered some unexpected trends.

Methane-munching microbes in soil might be more important than previously thought, a new study finds. Soil is an important carbon sink, and scientists are still learning much about the diversity of its microbial communities. They're being uncovered from Arctic soils to desert sands, and some of them are sucking down methane—a greenhouse gas about 27–30 times more potent than carbon dioxide over 100 years.

Firefighters have been battling a vast wildfire in the hills above Blaenavon in south Wales, spreading across more than 4,000 hectares (9,900 acres), for three weeks.

Dense evergreen plantations in Canada's boreal forest absorb so much winter sunlight that the resulting surface warming can offset 6% to 20% of the climate benefit they are credited with. Canada's current carbon accounting frameworks measure the carbon stored but largely omit the heat absorbed by these forests, according to a new policy brief from the United Nations University Institute for Water, Environment and Health (UNU-INWEH). The result is inflated mitigation estimates and public investment in forests that may not deliver the cooling they promise.

As competition between the United States and China intensifies over critical minerals, pressure is mounting to begin exploitation of deep-sea minerals before a code to regulate mining of the seabed in areas beyond national jurisdiction is agreed to.

Source: Journal of Geophysical Research: Biogeosciences

Methane-munching microbes in soil might be more important than previously thought, a new study finds. Soil is an important carbon sink, and scientists are still learning much about the diversity of its microbial communities. They’re being uncovered from Arctic soils to desert sands, and some of them are sucking down methane—a greenhouse gas about 27–30 times more potent than carbon dioxide over 100 years.

Soil methanotrophs are organisms capable of biologically removing methane from the atmosphere. Current estimates vary widely, but soil methanotrophs may store an average of 28–35 gigatons of methane per year globally. And even that could be an underestimate, scientists suspect.

Previous efforts to estimate the global biological methane source from wetlands and inland fresh waters primarily used process-based modeling, which focuses on biogeochemical processes, and atmospheric inversion modeling, which starts with methane concentrations in the atmosphere and works backward to determine emission sources.

But estimates from these two approaches tend to differ. The bottom-up, process-based estimates of methane emissions from wetlands and inland fresh waters were higher than the top-down, atmosphere-based estimates. A larger soil sink could help offset some of these discrepancies, bringing net bottom-up estimates closer to those inferred from the atmosphere.

Oh et al. dig in to reconcile that discrepancy and refine the estimate of how much methane-munching soil microbes contribute to the global methane sink.

The authors added a third kind of modeling: data-driven machine learning. By running the three kinds of models in parallel and comparing their results, the researchers hoped to home in on a more reliable estimate with smaller uncertainties. They also tweaked the microbial dynamics in the process-based model and included previously overlooked places and microbes.

The three-pronged approach worked. Both process-based and machine learning models yielded similarly sized sinks. According to their estimates, microbes in soils take up 40–45 gigatons of global methane per year, significantly higher than estimates from older approaches. That value is also larger than estimates in global climate assessments, such as that of the Intergovernmental Panel on Climate Change. When incorporated in top-down atmospheric inversions, this larger soil methane sink also improved the models’ ability to reproduce observed atmospheric methane and its stable carbon isotope composition.

The findings suggest that the microbial soil methane sink has been underestimated and that the revised three-model approach may improve global carbon cycle modeling. (Journal of Geophysical Research: Biogeosciences, https://doi.org/10.1029/2025JG009668, 2026)

—Rebecca Dzombak, Science Writer

Citation: Dzombak, R. (2026), It takes three to model methane right, Eos, 107, https://doi.org/10.1029/2026EO260268. Published on 20 August 2026. Text © 2026. 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.

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

The Eastern and Southern Alps deform slowly compared with many tectonically active regions worldwide, making their ongoing movements especially difficult to detect. Grützner et al. [2026] provide an unusually detailed synthesis of decades of research across nine countries, combining evidence from different datasets, methods, catalogues, and research traditions. By comparing and reconciling these sources, the study creates a comprehensive framework for understanding how active faults and earthquakes relate to climate, the structure of Earth’s outer rocky layer, and deeper processes within the planet.

The results show that present-day deformation is controlled mainly by a strong crustal block beneath the Dolomites pushing into the Alps, movement between relatively rigid blocks of rock, and uplift as the land rebounds following the melting of ice-age glaciers. The slow movement of hot mantle rock deep within Earth appears to play a smaller role than previously proposed. The areas of greatest earthquake hazard are concentrated along the southern edge of the Alps and where the Alps meet the Dinarides. This synthesis will provide an important reference for researchers studying the Alps and other slowly deforming regions, where weak tectonic signals and varied datasets make earthquake-hazard assessment particularly challenging.

Citation: Grützner, C., Petersen, G., Serpelloni, E., Metzger, S., Moernaut, J., Ustaszewski, K., et al. (2026). Active tectonics of the eastern and southern Alps – Crustal response to deep processes? A review. Tectonics, 45, e2025TC009267. https://doi.org/10.1029/2025TC009267

—Lothar Ratschbacher, Associate Editor; and Djordje Grujic, Editor, Tectonics

Text © 2026. The authors. CC BY-NC-ND 3.0
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Global mangrove cover—vegetation vital to tackling climate change—has increased over the past 40 years, despite significant losses in some key regions, according to a new analysis.

At least 107 people were killed in major failure at an artisinal mine on the border with Cameroon.

In the afternoon of 18 August 2026, a large landsldie occurred at an artisinal gold mine at Zamboye (also spelt Zamboï) in the Central African Republic. The landslide was caught on videos that have been widely shared (there are two different angles). Please be aware that it makes uncomfortable viewing:-

I am unsure of the precise location of this accident. It is described as being close to Garoua-Boulaï, which is located at [5.888, 14.550].

News reports indicate that 107 bodies have been recovered to date, but that the toll might be higher.

At first sight, the behaviour of the miners looks odd – there is a huge crowd directly in the path of what is clearly an unstable slope. I suspect though that the videos capture just one of a series of failures. This screenshot is from early in the recorded failure sequence:

Screenshot of the video of the 18 August 2026 gold mine landslide at the Zamboye (Zamboï) mining site in the Central African Republic.

It appears to me that this landslide moves onto, and mobilises, debris from an earlier failure, which can be seen in the bottom right hand corner of the image. I would speculate that the failure event(s) captured in the videos might be just one of a series of failures.

Were the crowds trying to rescue people already buried when this recorded landslide occurred?

Of course, this serves to remind us of the horrific dangers faced in artisinal mines, such as the one at Zamboye.

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Photovoltaic technology, most commonly seen as bulky solar panels used on solar farms, is expected to become a dominant energy source by 2050. But these panels are often installed on land that might otherwise be used to grow crops and feed a burgeoning population.

Official flood maps shape disaster preparedness, insurance decisions and urban planning, but large parts of the United States remain unmapped or under-mapped. This means some communities may be left unaware of the risks they face, limiting their ability to prepare for future floods.

A new analysis of ice cores collected from the Andes in Peru has produced the first global record of historical tropical methane, filling a critical gap in our understanding of the origins of Earth's greenhouse gases.

Between 2021 and 2023, Antarctica appeared to be growing. Heavy snowfall fueled by wetter weather caused parts of the continent to gain mass, leading some to question whether climate change is really causing the ice to melt. However, a new study shows that the precipitation increase was an anomaly related to extra-warm tropical ocean temperatures, not part of a long-term trend.

Editors’ Vox is a blog from AGU’s Publications Department.

Every lightning flash has one defining moment: the return stroke, an intense surge of electric current that rockets upward along the ionized channel at a sizable fraction of the speed of light, unleashing the blinding flash, the crack of thunder, and the burst of radio energy that detection networks use to pinpoint strikes worldwide. Despite decades of study, a full, self-consistent explanation for why this current takes the shape it does — its rapid rise, its slower decay, its weakening and spreading as it climbs — has remained elusive.

In a new article published in Reviews of Geophysics, Caitano da Silva and colleagues at New Mexico Tech show that the Telegrapher’s Equations, a compact framework describing how electrical signals propagate along any conductor, can be adapted into a physically transparent model that derives all of these features from first principles — and reconciles them with decades of field and laboratory measurements. Here, the authors answer a few questions about their work.

In simple terms, what is the “lightning return stroke current”?

When a downward-moving leader from a thundercloud gets close enough to the ground, a channel of ionized air connects cloud to ground. At that instant, a powerful surge of electric current — the return stroke — rushes upward along this newly formed conducting path at a sizable fraction of the speed of light, carrying tens of thousands of amperes. This surge is what produces the visible flash, heats the air explosively to create thunder, and radiates the burst of radio waves that lightning detection networks use to pinpoint strikes. It’s the most energetic and consequential part of a lightning flash, even though it typically lasts only tens of microseconds.

Why are return strokes important to study?

The return stroke current is responsible for most of lightning’s real-world impacts. It causes billions of dollars in damage annually to power transmission lines and communication infrastructure, and it’s a leading ignition source for wildfires. It is also the atmosphere’s main natural source of nitrogen oxides, which influence atmospheric chemistry on regional and global scales. On top of that, the radio pulse the return stroke emits is exactly what national and global lightning-detection networks measure to locate strikes, supporting both hazard mitigation and weather forecasting. Understanding the physics that shapes this current — its peak strength, its speed, and how quickly it weakens — is therefore essential for protecting infrastructure and for interpreting the remote-sensing data scientists rely on.

What are the main types of models scientists use to simulate the return stroke?

Researchers have taken a few different approaches. “Gas-dynamic” models solve the detailed physics of how the current heats and expands the channel of air, which is useful for calculating channel temperature and chemical byproducts, but they need the current as an input rather than predicting it. To calculate the current and resulting electromagnetic fields directly, three families of models exist: “engineering models,” which simply assume a plausible mathematical shape for the current and how it weakens with height; “antenna-theory models,” which apply full numerical electromagnetics; and “distributed-circuit models,” which treat the lightning channel as an electrical transmission line. This last approach, governed by the Telegrapher’s Equations, is the focus of this review.

What are the Telegrapher’s Equations, and what can they tell us about return strokes?

The Telegrapher’s Equations describe how current and voltage evolve along any conductor with distributed resistance, inductance, and capacitance — they are widely used to model how signals travel in power transmission cables. We model the lightning channel as two concentric cylinders: a thin core that carries the current and a wider sheath that stores the associated charge. Solved this way, the equations self-consistently explain the current’s signature shape at ground level — a fast rise, set by how quickly the leader tips connect and thermalize, followed by a slower decay, governed by the channel’s electrical resistance. We also explain why the current wave travels at a fraction of light speed, why it weakens as it climbs, and why the current pulse disperses over distance — all derived from a handful of physical parameters rather than assumed curve shapes.

(a) Photograph of a lightning return stroke. (b-c) Schematic representation of the return stroke as a charge-neutralization wave. (d) Numerical discretization of the problem. Credit: da Silva et al. [2026], Figure 1

What are the benefits and limitations of this approach compared to other techniques?

Its biggest strength is speed paired with insight: the model runs orders of magnitude faster than full electromagnetic or gas-dynamic simulations, yet still yields exact analytical solutions in several limiting cases and explains why the empirical “engineering models” long used in industry take the mathematical forms they do. That transparency has made it a teaching tool in its own right — the model anchors how the return stroke is taught in the “Physics of Lightning” graduate course at New Mexico Tech, letting students derive lightning’s key features from first principles rather than take them on faith. Its main limitation is a simplifying assumption baked into the mathematics: it treats the electromagnetic fields as purely transverse to the channel, which breaks down for real, tortuous, branching channels. The model also simplifies the charge-storing corona sheath and requires care at the channel’s upper boundary to avoid artificial wave reflections.

What remaining questions or knowledge gaps need more research?

Two open questions stand out. The first is how to extend this framework — built around a single, straight channel — to capture the full complexity of a real lightning flash: its three-dimensional, branching geometry, and the sequence of multiple return strokes and other subprocesses, such as M-components and continuing currents, that typically follow the first stroke down the same channel.

The second is how to properly incorporate corona sheath dynamics into the Telegrapher’s Equations themselves. The present model treats the sheath’s charge as spreading out instantaneously over a fixed radius, but in reality, the sheath expands and charges on a finite timescale, and self-consistently coupling that behavior to the equations remains unresolved. Solving both problems — geometric realism and sheath physics — would sharpen predictions of lightning’s electromagnetic fields and its hazards to infrastructure, wildfires, and atmospheric chemistry.

—Caitano da Silva (caitano.dasilva@nmt.edu, 0000-0003-3728-3035), New Mexico Institute of Mining and Technology, United States; Logan Baeza, New Mexico Institute of Mining and Technology, United States; Jacob Wemhoner (0000-0002-8917-3009), New Mexico Institute of Mining and Technology, United States; and Saulo Orizaga (0009-0000-9635-8100), New Mexico Institute of Mining and Technology, United States

Editor’s Note: It is the policy of AGU Publications to invite the authors of articles published in Reviews of Geophysics to write a summary for Eos Editors’ Vox.

Citation: da Silva, C., L. Baeza, J. Wemhoner, and S. Orizaga (2026), Decoding the origins of lightning’s violent currents, Eos, 107, https://doi.org/10.1029/2026EO265031. Published on 19 August 2026. This article does not represent the opinion of AGU, Eos, or any of its affiliates. It is solely the opinion of the author(s). 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.

Source: AGU Advances

This is an authorized translation of an Eos article. 本文是Eos文章的授权翻译。

北极地区冻土覆盖的山坡上会呈现出一系列几何纹理，从圆形、条纹到多边形图案，不一而足。此外，还存在冻融泥流（solifluction）形态，即部分融化的永久冻土沿坡下滑时留下的痕迹。这些冻融泥流形态看起来像是平坦的梯田状土壤，如同一个巨大的阶梯，与梯田底部圆形的土壤块状物组合在一起。

随着气候变化加剧冻土融化的速度，了解这些图案的形成方式对于预测和修复北极地区不稳定的坡面至关重要。同时，这也有助于研究火星过去的气候状况，因为科学家已经在火星表面发现了类似的地形。然而，冻融泥流形态的形成机制一直难以解释。在一项新的研究中，Glade等人利用数学和物理模型以及遥感技术，解释了冻融泥流地形的形成机制。

冰冻土壤的移动速度非常缓慢，每年仅移动几毫米到几厘米，其行为也十分复杂，有时像流体，有时又像固体。这种复杂性源于水分和温度的季节性变化，以及土壤本身的固有物理规律。

研究人员排除了其他常见的流体类比物，例如墙上的油漆滴落、熔岩褶皱中的屈曲不稳定性以及滚动波。研究人员回顾了土壤学文献，运行了基于物理过程的计算机模型，对梯田与叶状结构的形成进行了模拟，并对不同流体行为进行了数学建模。

最终，他们找到了一个合适的类比物：在一种名为“Oobleck”的非牛顿流体中形成的波浪。Oobleck是一种由玉米淀粉和水混合而成的非牛顿流体，在不同应力下，其速度会发生变化，而且与直觉相反，施加的压力越大，它就越难被推动。

由于Oobleck具有独特的物理性质，它常被用于教学实验，且与研究人员在自然界观测到的冻土地貌特征高度吻合。土壤湿度的差异可能导致土壤流速不同，从而形成空间上不均匀的土壤堆积，最终在泥流过程再次开始之前坍塌。

研究人员指出，目前这一模型仍有其局限性。Oobleck反映的仅仅是流变特性，也就是所研究土壤（或流体）的物质构成。现实世界中的冻土，远比玉米淀粉和水的简单混合物要复杂得多。

除此之外，地形和植被等因素也会影响其形态，而不仅仅是物质组成。土壤堆积的前提是必须存在一个隆起结构，同时还需要足够的土壤湿度来积累冰层。

研究人员希望在实地验证他们的模型，但由于这些地貌特征的形成需要数百年甚至更长时间，直接观察其演变过程极为困难，但也并非不可能，他们决心尝试。(AGU Advances, https://doi.org/10.1029/2026AV002392, 2026)

—科学撰稿人Rebecca Dzombak

Text © 2026. AGU. CC BY-NC-ND 3.0
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Volcanoes emit smoke. Beneath a volcano lies a huge chamber filled with liquid magma. A series of earthquakes means an eruption is imminent. And if a "supervolcano" like Yellowstone were to awaken, a global catastrophe would be upon us. These are images and ideas that regularly crop up in news reports, documentaries and on social media.

Editors’ Highlights are summaries of recent papers by AGU’s journal editors. Source: Journal of Geophysical Research: Earth Surface

Many exciting topics in geomorphology revolve around boundaries. The boundaries between hillslopes and river channels may seem obvious in an active landscape, but are far from trivial to detect objectively from digital elevation data. A pragmatic and routine solution is to use a fixed contributing catchment area to separate hillslopes from channels. The resulting geometry of the channel network then allows estimates of local steepness as a key metric of how rivers incise in response to rock uplift, and more generally, how landscapes respond to tectonic drivers. Yet, these estimates ultimately hinge on the choice of where channels begin.

Fox et al. [2026] explore how this choice matters: they showcase a numerical model of hillslope and channel evolution that predicts that the boundary between the two domains systematically shifts with varying rates of rock uplift. According to the model, more rapid uplift tends to lengthen hillslopes such that they can extend well beyond the arbitrary minimum catchment area used to characterize channels exclusively. The effect is that hillslope geometry contaminates estimates of channel steepness, and thus any inference about how river incision responds to changes in rock uplift. What is commonly reported as “channel steepness” as a metric of river form and adjustment might indeed carry an undesired contribution of hillslopes and their processes such as soil creep or debris flow. Clearly it is time to acknowledge a more flexible perspective of where channels begin, especially if using their geometry in models of landscape evolution.

Citation: Fox, M., Goren, L., & Adams, B. A. (2026). Non-linear hillslopes produce apparent non-linear river erosion models. Journal of Geophysical Research: Earth Surface, 131, e2025JF008753. https://doi.org/10.1029/2025JF008753   

—Oliver Korup, Associate Editor, JGR: Earth Surface

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Source: Journal of Advances in Modeling Earth Systems (JAMES)

Photovoltaic technology, most commonly seen as the bulky solar panels used on solar farms, is expected to become a dominant energy source by 2050. But these panels are often installed on land that might otherwise be used to grow crops for feeding a burgeoning population.

Agrivoltaics aims to solve this problem by planting crops around or underneath rows of solar panels, allowing for more efficient land use. In previous studies, solar panels were shown to help shade and protect certain crops as well as increase soil moisture, suggesting that carefully designed systems could support both agriculture and clean energy production.

Existing agrivoltaic research, however, tends to focus on one aspect of this process at a time—for example, light availability or crop growth—rather than addressing the nuanced interactions between microclimates, crop type, light, and panel type. Hosseini et al. share a new model that can simulate the microclimates beneath solar panels and even addresses the heat stress that workers might face in actual conditions.

The new model simulates the interactions between solar panels, crops, soil, air and water movement, and carbon dioxide uptake by tracking how energy, momentum, and mass move through the agrivoltaic system. The researchers used agrivoltaic site data, including leaf temperature measurements taken in Davis, Calif., and soil temperatures taken in Chicago City, Minn., to assess how the model’s efforts matched real-world conditions.

They then applied the model to a hypothetical agrivoltaic tomato farm using weather data from a hot, humid day in Princeton, N.J., a representative location for the densely populated mid-Atlantic region, where food and energy are both in high demand.

Compared to tomatoes grown in an open field, tomatoes grown under solar panels experienced leaf temperatures that were 1.84°C cooler during the day overall and up to 7.56°C cooler during peak afternoon heat, reducing water loss through evapotranspiration by 22.4%. Even though the simulated crops received 47% less sunlight, their carbon uptake declined by only 31%, suggesting that more temperate conditions lowered heat stress and partially offset the effects of increased shade.

The solar panels themselves were also 5.6°C cooler during the daytime than panels in bare soil, allowing them to recover about 15% of the efficiency that is lost during hotter temperatures. The average perceived temperatures for humans decreased by 4.46°C during working hours, implying important occupational health and safety benefits for farmworkers. The researchers suggest this model can be used to examine the benefits of agrivoltaic farms as well as other climate and crop combinations. (Journal of Advances in Modeling Earth Systems (JAMES), https://doi.org/10.1029/2025MS005588, 2026)

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

Citation: Owen, R. (2026), Solar panels can cool crops—and workers, Eos, 107, https://doi.org/10.1029/2026EO260241. Published on 19 August 2026. Text © 2026. 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.

The external review of the Mount Maunganui Beachside Holiday Park landslide is extremely critical of the local authority in their approach to the management of the well-documented landslide hazard and risk at the site.

The external review commissioned by Tauranga City Council (TCC) into the 22 January 2026 Mount Maunganui Beachside Holiday Park landslide released its report today. It has been extensively covered in the New Zealand media. The conclusions are quite devastating for TCC, but are also likely to have wider implications for the management of risk from natural hazards across New Zealand.

The 22 January 2026 landslide at Mount Maunganui in New Zealand. Image from the TCC external review.

It is important to remember the terms of reference of this external review, which was undertaken by Hon. Paul Davison KSO KC:

“the external review examines the facts, timeline and decision-making processes leading up to the landslide, the adequacy of risk assessments and monitoring systems, and any lessons or improvements needed to strengthen future safety. The external review is separate from the Government Inquiry and the investigations currently being undertaken by the Coroner, Police and WorkSafe.”

So this review does not look at the initiation of the landslide – that will come in due course – it is really about the management of the risk. The conclusions are summarised in this section of the report (p. 204):-

What this Review does find is that this tragedy was, in the end, preventable. I do not mean by that that anyone could have known that this slope would fail at this moment, on this particular morning — no one could. I mean something more deeply troubling: that the hazard was known, that an effective and inexpensive means of managing the risk it posed had twice been recommended, and that the Council had every opportunity to put it in place. Had it done so, the most consequential decision of 22 January — whether to move people away from the foot of the slope — would not have been left to the unaided judgement of whoever happened to be on site that morning. It would have been made in advance, against defined criteria that the readily observable conditions of that day would plainly have met. What was required was not extraordinary foresight. It was the robust operational processes and discipline required of a well-run organisation: that a known risk to life be owned by someone, recorded, escalated, and followed through until an effective means of mitigating it was in place, and that those left in charge of the campground were equipped to recognise the danger, and ready to act quickly and effectively if ever required.

The report highlights that multiple studies showed that the risk to life at the campsite was unacceptably high – indeed, by some calculations the impact of this event was lower than had been feared. This is primarily because individuals at the site recognised that the risk was high and started to raise the alarm. If the Mount Maunganui Beachside Holiday Park landslide had occurred in the early hours of the morning the toll would probably have been higher.

There is little in this report with which I disagree, and the consequences for TCC are likely to be serious. I’m unsure as to the detail of the New Zealand judicial system, but in the UK this report would open the path to both civil and criminal court action, with the latter potentially occurring at both the institutional and individual level.

If there is one thing that worries me, it is that the the report does not fully recognise that early warning systems and evacuation plans are not a magic bullet. There is strong evidence from multiple settings that they can be dogged by uncertainty, equipment failures, false alarms and a lack of willingness from individuals to respond in the way that is planned.

But that is not an excuse for failing to have such a system in place.

Apart from the direct impact on TCC and its members, this report is likely to have profound implications for landslide risk management in New Zealand. Take this recommendation for example:

“For every populated site controlled by TCC, exposed to a natural-hazard risk to life assessed as Medium or higher, TCC should require — not merely consider — the development and maintenance of a Trigger Action Response Plan. The TARP should: be capable of immediate implementation in a simple initial form (for example, staged evacuation of defined runout zones when rainfall exceeds a defined return interval threshold over a defined duration), and be refined over time as a living document; link specific, observable or measurable triggers — defined rainfall thresholds, antecedent soil-moisture, and visible signs such as turbid water from the toe of a slope, tension cracking, bulging or changes in seepage — to specific, staged actions up to and including full evacuation; empower designated site personnel to act on a trigger immediately, without needing approval from someone higher in the TCC organisation; identify who holds each responsibility and the communication and escalation protocol; and recognise that evacuation/avoidance is a higher-order control than engineered consequence-reduction.”

Whilst this recommendation is TCC specific, it is inevitably going to have implications across all local authorities in New Zealand. The country inevitably has many, many sites in which “natural-hazard risk to life” is medium or above. This recommendation is going to require a very extensive revisit of risk management at those locations. In a country with a small population and a very large, hazard-prone landmass, that is going impose a major burden.

It is worth noting that TCC has “today accepted the findings and recommendations from the external review into the landslide at Mount Maunganui Beachside Holiday Park on 22 January 2026”.

The reverberations of the tragic Mount Maunganui Beachside Holiday Park landslideare going to continue for a long time.

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Large earthquakes can dramatically reshape mountain landscapes by triggering thousands of landslides and rapidly accelerating erosion. However, the reasons why some mountain regions experience intense, long-lasting erosion after large earthquakes while others show only limited responses have been poorly understood.