Subsequent Fire Research Articles

Spatiotemporal patterns and drivers of extreme fire severity in Spain for the period 1985–2018

Extreme fire severity patterns driven by climate change have deep consequences on vegetation, subsequent fire regimes and have consequences on the effectiveness of extinction. In this work, we aimed to determine if extreme fire severity defined as the 90th percentile of RdNBR has changed in Spain in the last 3 decades, if extreme fire severity patterns have differed among the different vegetation types and what drivers have influenced extreme fire severity in both summer and non-summer fires. We have used perimeters of large wildfires (≥100 ha, n = 1719) from 1985 to 2018 in four pyroregions and the main dominant vegetation types. We have analyzed time series for each pyroregion and vegetation type to determine if there were significant trends and breakpoints in extreme fire severity. We have also analyzed the effects of drought, weather, topography and vegetation on extreme fire severity in seasonal wildfires.Extreme fire severity increased in summer fires from 1985 to 2018, especially in the East and North pyroregions, while the Southwest pyroregion reached highest values in summer. There has been an increase of severity in shrubland, mosaic vegetation and conifer forests in summer. Broadleaved forests had the lowest values of fire severity and did not show any trend in the period considered. The most important drivers of extreme fire severity are, in order of importance, pyroregion, elevation, slope, vapor pressure deficit (VPD) and vegetation type for summer fires, and VPD, vegetation types, pyroregion, windspeed and drought for non-summer fires. Global change is increasing climate-related events. Our results indicate that extreme fire severity in summer has been on the rise in recent decades in Spain, suggesting that, in a climate warming context, without strategic management of these increasingly flammable landscapes, further increases may be likely.

Prescribed fire regimes influence responses of fungal and bacterial communities on new litter substrates in a brackish tidal marsh.

Processes modifying newly deposited litter substrates should affect fine fuels in fire-managed tidal marsh ecosystems. Differences in chemical composition and dynamics of litter should arise from fire histories that generate pyrodiverse plant communities, tropical cyclones that deposit wrack as litter, tidal inundation that introduces and alters sediments and microbes, and interactions among these different processes. The resulting diversity and dynamics of available litter compounds should affect microbial (fungal and bacterial) communities and their roles in litter substrate dynamics and ecosystem responses over time. We experimentally examined effects of differences in litter types produced by different fire regimes and litter loads (simulating wrack deposition) on microbial community composition and changes over time. We established replicated plots at similar elevations within frequent tidal-inundation zones of a coastal brackish Louisiana marsh. Plots were located within blocks with different prescribed fire regimes. We deployed different measured loads of new sterilized litter collected from zones in which plots were established, then re-measured litter masses at subsequent collection times. We used DNA sequencing to characterize microbial communities, indicator families, and inferred ecosystem functions in litter subsamples. Differences in fire regimes had large, similar effects on fungal and bacterial indicator families and community compositions and were associated with alternate trajectories of community development over time. Both microbial and plant community compositional patterns were associated with fire regimes, but in dissimilar ways. Differences in litter loads introduced differences in sediment accumulation associated with tidal inundation that may have affected microbial communities. Our study further suggests that fire regimes and tropical cyclones, in the context of frequent tidal inundation, may interactively generate substrate heterogeneities and alter microbial community composition, potentially modifying fine fuels and hence subsequent fires. Understanding microbial community compositional and functional responses to fire regimes and tropical cyclones should be useful in management of coastal marsh ecosystems.

Moderating effects of past wildfire on reburn severity depend on climate and initial severity in Western US forests.

Rising global fire activity is increasing the prevalence of repeated short-interval burning (reburning) in forests worldwide. In forests that historically experienced frequent-fire regimes, high-severity fire exacerbates the severity of subsequent fires by increasing prevalence of shrubs and/or by creating drier understory conditions. Low- to moderate-severity fire, in contrast, can moderate future fire behavior by reducing fuel loads. The extent to which previous fires moderate future fire severity will powerfully affect fire-prone forest ecosystem trajectories over the next century. Further, knowing where and when a wildfire may act as a landscape-scale fuel treatment can help direct pre- and post-fire management efforts. We leverage satellite imagery and fire progression mapping to model reburn dynamics within forests that initially burned at low/moderate severity in 726 unique fire pair events over a 36-year period across four large fire-prone Western US ecoregions. We ask (1) how strong are the moderating effects of low- to moderate-severity fire on future fire severity, (2) how long do moderating effects last, and (3) how does the time between fires (a proxy for fuel accumulation) interact with initial fire severity, day-of-burning weather conditions, and climate to influence reburn severity. Short-interval reburns primarily occurred in dry- and moist-mixed conifer forests with historically frequent-fire regimes. Previous fire moderated reburn severity in all ecoregions with the strongest effects occurring in the California Coast and Western Mountains and the average duration of moderating effects ranging from 13 years in the Western Mountains to >36 years in the California Coast. The strength and duration of moderating effects depended on climate and initial fire severity in some regions, reflecting differences in post-fire fuel accumulation. In the California Coast, moderating effects lasted longer in cooler and wetter forests. In the Western Mountains, moderating effects were stronger and longer lasting in forests that initially burned at higher severity. Moderating effects were largely robust to fire weather, suggesting that previous fire can mediate future fire severity even under extreme conditions. Our findings demonstrate that low- to moderate-severity fire buffers future fire severity in historically frequent-fire forests, underlining the importance of wildfire as a restoration tool for adapting to global change.

Widespread impacts to precipitation of the East Palestine Ohio train accident

On 3 February 2023, a Norfolk Southern train derailment occurred in East Palestine, Ohio. The accident and subsequent fire resulted in the emissions of large amounts of hazardous compounds to the ambient atmosphere over many days. We used precipitation chemistry measurements routinely collected by the National Atmospheric Deposition Program (NADP) to estimate the spatial extent and chemical compounds deposited as a result of the accident. Our measurements revealed a large areal impact from the Midwest through the Northeast and likely Canada, and perhaps as far south as North Carolina (portions of 16 states, 1.4 million km2). Observations showed the expected high chloride concentrations, but also unexpectedly high pH (basic) and exceptionally elevated levels of base cations exceeding 99th percentiles versus the historic record. These results were consistent with the meteorological conditions and atmospheric trajectories, and were not due to highly-concentrated low volume precipitation samples or wildfires. The robust measurements of the NADP network clearly show that the impacts of the fire were larger in scale and scope than the initial predictions, and likely due to the uplift from the fire itself entraining pollutants into the atmosphere. A more detailed evaluation of the accident and resulting fire could further refine the full impact of the atmospheric concentrations, dry and wet deposition, and the more specific extent of the spatial impact.

The wildfire impacts of the 2017-2018 precipitation whiplash event across the Southern Great Plains

The Southern Great Plains of the United States is a region with a sharp zonal precipitation gradient that is prone to rapid transitions in precipitation extremes. Transitions from pluvial to drought conditions can lead to the green-up of vegetation during extreme rainfall, posing a considerable fire risk as the region rapidly transitions into drought. Such transitions have been studied in depth across regions such as California; however, limited studies have examined their impacts across the Southern Great Plains. The aim of this study was to examine the role of preceding precipitation whiplash events in providing fuel for wildfires, with 2017–2018 investigated as a case study. This study specifically demonstrates the relationship between precipitation, vegetation, and wildfires for the first time across the Southern Great Plains. Lag correlation analysis of historical data at our study site showed anomalously high precipitation 8 months prior to Spring wildfires, resulting in a significantly higher number of wildfires and acres burned. In particular, this study examined a highly impactful precipitation whiplash event that occurred during the Fall of 2017 across the Oklahoma and Texas panhandles, which preceded a mega-fire event in the Spring of 2018. Precipitation anomalies that were 137% of normal during the 2017 growing season rapidly cascaded into drought conditions with precipitation anomalies 21% of normal throughout the cool winter season. Excessive precipitation supported vigorous vegetation recovery and growth, with vegetation indices peaking at approximately 1 standard deviation above average during August 2017. However, the subsequent drought period rapidly desiccated the terrestrial surface. As a result, dozens of wildfires burned a total of 556 347 acres during March and April 2018, resulting in at least two fatalities, dozens of homes destroyed, and over 500 personnel dispatched to fight and mitigate the fires. Overall, this study highlights the significant role of preceding Fall precipitation whiplash events in fueling Spring wildfires across the Southern Great Plains, particularly exemplified by the impactful 2017–2018 case, highlighting the complex dynamics between extreme precipitation, vegetation growth, and subsequent fire risks in the region.

On the issue of the manufacture of ceramic structures in orthopedic dentistry

The article presents a review of ceramic materials used in modern orthopedic dentistry. Currently, the main types of orthopedic structures containing dental porcelain are metal-ceramic, metal-free ceramic crowns, as well as prostheses made using pressed ceramic technology, in particular veneers. All types of prostheses produced using dental porcelain have a common manufacturing technology, which consists in the sequential application of ceramic layers with their subsequent firing. Moreover, for each group of teeth, there are additional masses for firing, for example, masses of the cutting edge, masses simulating various effects (for example, blue, yellow and other shades, imitation of tooth growth lines). These masses are created in order to give future crowns the most natural and aesthetic appearance. All structural components (layers) of ceramics used in the manufacture of ceramic prostheses have a similar chemical composition. The raw material is feldspar glass with inclusions of crystalline quartz. Depending on the conditions of the reactions, the composition of mixtures can be varied and compounds with desired properties can be obtained using the phase analysis method, which will expand the range of domestic ceramic materials produced, which are currently quite scarce. This is especially relevant in modern conditions of import substitution.

Incorporating burn heterogeneity with fuel load estimates may improve fire behaviour predictions in south-east Australian eucalypt forest

Background Simulations of fire spread are vital for operational fire management and strategic risk planning. Aims To quantify burn heterogeneity effects on post-fire fuel loads, and test whether modifying fuel load estimates based on the fire severity and patchiness of the last fire improves the accuracy of simulations of subsequent fires. Methods We (1) measured fine fuels in eucalypt forests in south-eastern Australia following fires of differing severity; (2) modified post-fire fuel accumulation estimates based on our results; and (3) ran different fire simulations for a case-study area which was subject to a planned hazard reduction burn followed by a wildfire shortly thereafter. Key results Increasing fire severity resulted in increased reduction in bark fuels. In contrast, surface and elevated fuels were reduced by similar amounts following both low-moderate and high-extreme fire severity. Accounting for burn heterogeneity, and fire severity effects on bark, improved the accuracy of fire spread for a case study fire. Conclusions Integration of burn heterogeneity into post-burn fuel load estimates may substantially improve fire behaviour predictions. Implications Without accounting for burn heterogeneity, patchy burns of low severity may mean that risk estimations are incorrect. This has implications for evaluating the cost-effectiveness of planned burn programmes.

Simulations-based investigation of the effectiveness of fire suppression techniques for safe, large-scale storage of Li-ion batteries

Thermal runaway and subsequent fire in Li-ion cells and battery packs is of much concern in the safety of practical electrochemical energy storage systems. While much of the past work in this direction has focused on single cells or small packs, there is a relative lack of understanding of thermal runaway related fire and fire suppression strategies for large-scale systems, for example in storage and transportation of Li-ion cells. This work presents a simulations-based investigation of strategies for effective prevention and suppression of thermal runaway propagation and resulting fire in pallets containing a large number of Li-ion cells. The impact of location, orientation and flowrate in sprinklers supplying a liquid coolant is quantitatively investigated. It is shown that a minimum flowrate is needed for effective fire containment, beyond which, additional flowrate does not offer much incremental benefit. The orientation of sprinklers with respect to the trigger pallet undergoing thermal runaway is found to strongly impact the effectiveness of fire suppression. Fire suppression in the case of vertically stacked pallets is also investigated. Interesting synergistic effects involving a combination of liquid coolant along with one or more suppressant gases is demonstrated. The key output of this work is a computational model that quantitatively predicts the effectiveness of fire suppression techniques for battery transportation and storage. Results presented here offer a fundamental understanding of an important practical problem in battery-based energy storage. Results may form the basis of design and optimization to ensure the safety of large-scale storage and transportation of Li-ion cells.

Non fire-adapted dry forest of Northwestern Madagascar: Escalating and devastating trends revealed by Landsat timeseries and GEDI lidar data.

Ankarafantsika National Park (ANP), the last significant remnant of Northwestern Madagascar's tropical dry forests, is facing rapid degradation due to increased incidences of fire. This poses severe threats to biodiversity, local livelihoods, and vital ecosystem services. Our study, conducted on 3,052-ha of ANP's pristine forests, employed advanced remote-sensing techniques to assess fire impacts during the past 37 years. Our aims were to understand historical fire patterns and evaluate forest recovery and susceptibility to repeated fires following initial burns. Using data from multiple Landsat satellite sensors, we constructed a time series of fire events since 1985, which revealed no fire activity before 2014. The Global Ecosystem Dynamics Investigation (GEDI) lidar sensor data were used to observe forest structure in both post-fire areas and undisturbed zones for comparison. We recorded six fire incidents from 2014-2021, during which the fire-affected area exponentially grew. A significant fire incident in October 2021 impacted 1,052 hectares, 59% of which had experienced at least one fire in two-to-four years prior, with 60% experiencing two preceding incidents: one in 2017 and another in 2019. The initial fire drastically reduced plant cover and tree height, with subsequent fires causing minor additional loss. Post-fire recovery was negligible within the initial four years, even in patches without recurrent fires. The likelihood for an initial burn to trigger subsequent fires within a few years was high, leading to larger, more severe fires. We conclude that ANP's dry forests exhibit high vulnerability and low resilience to anthropogenic fires. Prompt preventive measures are essential to halt further fire spread and conserve the park's unique and invaluable biodiversity.

Human Factors Contributing to Accidents and Disasters in Road Transport of Petroleum Products in Kenya

Over the past few decades, Africa has witnessed enormous increase in the number of accidents take occur during road transport of petroleum products. Some of these accidents escalated into disasters because of release of products, with subsequent explosion and fire, resulting in several injuries and fatalities. With the Sendai Framework for Disaster Risk Reduction (DRR), the focus is on disaster risk reduction, rather than disaster response. This paper identifies human factors as a major cause of road transport accidents that lead to disasters when petroleum products are released. The study area was Kenya, but the findings are applicable across the continent. The Tripod Beta methodology, an incident investigation tool, was applied to analyse some of the disasters that had occurred in the downstream petroleum sub-sector in Kenya. The analysis identified root causes of accidents and highlighted the need to focus on tanker drivers as the key stakeholders for risk reduction. The root causes were applied in the development of the questionnaire that was used in a survey. The survey was carried out using random sampling, with a sample size of 391 tanker drivers. The study concluded that tanker drivers in the age group of 30-40 years, with 6-10 years’ driving experience and minimum educational level of secondary school, displayed the best performance in prevention of accidents and spills that could lead to disasters. Tanker drivers who meet these criteria should be the target of recruitment by transporters, followed by structured safety training, to achieve Goal Zero: no accident, no spill, and no disaster in the industry.

Adversarial learning for robust battery thermal runaway prognostic of electric vehicles

The thermal runaway risk in batteries is a critical issue affecting their safety. Although considerable research is dedicated towards the thermal runaway prognostic of batteries, a common challenge remains that how to reduce the false positive rate to enable practical real world application. To address this problem, this paper proposes a robust thermal runaway prognostic method for Li-ion batteries using a generative adversarial network. Specifically, the model utilizes the charging curves of batteries as features during training to reduce the randomness of sparse data and enhance the robustness of the model. A resampling algorithm is proposed to realize the standardized conversion of the charging curve to retain the complete charging information. By employing a one-class generative adversarial network, the method generates a detection model that provides a reference normal curve for the original battery charging process, detecting potential anomalies. Real accident data of electric vehicles that experienced thermal runaway and subsequent fires is used to verify the performance of the model. Experimental results show that the proposed method can identify all abnormal cells with a false positive rate of 1.75% before thermal runaway occurs, reducing 7.54% to 31.18% false positive rate compared to existing methods.

Simulation and experimental study of buried natural gas pipeline leak detection based on sound source characteristics

Buried pipe-line leakage will affect the thermal characteristics of the soil environment, leading to a poor soil environment. In addition, leakage of natural gas possibly produces an explosion and subsequent fire, which has fatal harm. Sustainable detection of underground gas pipe-line leaks is a significant part of current research. In this study, a method for leak detection of buried natural gas polyethylene pipe-lines based on sound source characteristics is investigated. The simulation software was applied in analyzing the variation of leakage rate and sound source in buried pipes under different leakage conditions including mainly different leakage apertures and pipe pressures. Also, an experiment platform was built to verify the simulation results. These results can provide help for gas pipe-line leakage detection and safety protection.

Improvement of mechanical properties of ceramic green body and fired body by aging of inorganic binder in ceramic slurry for 3D printing

Fabrication of ceramic bodies with complex structures via photopolymerization-based 3D printing with minimal deformation during the inevitable heat treatment necessitates the development of a photopolymerizable ceramic slurry. This study prepared a photocurable slurry using a photocurable resin and particles coated with an inorganic binder. The condensation efficiency of the inorganic binder was improved by applying an aging process to the green bodies, which in turn improved the fracture strength and enhanced the glass conversion efficiency of the particles during the subsequent firing process. The exceptional mechanical properties of the fired bodies fabricated using inorganic binder-coated starting particles can be attributed to the glass matrix formed between the particles rather than the particle-to-particle interfaces. We believe this study demonstrates the feasibility of fabricating ceramic bodies with minimal shrinkage and distortion compared to conventionally sintered bodies.

Identifying and managing disturbance-stimulated flammability in woody ecosystems.

Many forest types globally have been subject to an increase in the frequency of, and area burnt by, high-severity wildfire. Here we explore the role that previous disturbance has played in increasing the extent and severity of subsequent forest fires. We summarise evidence documenting and explaining the mechanisms underpinning a pulse of flammability that may follow disturbances such as fire, logging, clearing or windthrow (a process we term disturbance-stimulated flammability). Disturbance sometimes initiates a short initial period of low flammability, but then drives an extended period of increased flammability as vegetation regrows. Our analysis initially focuses on well-documented cases in Australia, but we also discuss where these pattens may apply elsewhere, including in the Northern Hemisphere. We outline the mechanisms by which disturbance drives flammability through disrupting the ecological controls that limit it in undisturbed forests. We then develop and test a conceptual model to aid prediction of woody vegetation communities where such patterns of disturbance-stimulated flammability may occur. We discuss the interaction of ecological controls with climate change, which is driving larger and more severe fires. We also explore the current state of knowledge around the point where disturbed, fire-prone stands are sufficiently widespread in landscapes that they may promote spatial contagion of high-severity wildfire that overwhelms any reduction in fire spread offered by less-flammable stands. We discuss how land managers might deal with the major challenges that changes in landscape cover and altered fire regimes may have created. This is especially pertinent in landscapes now dominated by extensive areas of young forest regenerating after logging, regrowing following broadscale fire including prescribed burning, or regenerating following agricultural land abandonment. Where disturbance is found to stimulate flammability, then key management actions should consider the long-term benefits of: (i) limiting disturbance-based management like logging or burning that creates young forests and triggers understorey development; (ii) protecting young forests from disturbances and assisting them to transition to an older, less-flammable state; and (iii) reinforcing the fire-inhibitory properties of older, less-flammable stands through methods for rapid fire detection and suppression.

Mapping Tree Mortality Caused by Siberian Silkmoth Outbreak Using Sentinel-2 Remote Sensing Data

The Siberian silkmoth is one of the most dangerous coniferous forests pests. Siberian silkmoth outbreaks cause massive defoliation and subsequent forest fires over vast areas. Remote forest disturbance assessments performed after an outbreak make it possible to assess carbon emissions and the potential for natural regeneration, estimate forest fire danger, and reveal the need to implement forest management practices. The goal of the present research was to investigate the use of modern satellite imagery of medium spatial resolution to estimate the percentage of dead trees in a given area. The subject of this study is the Siberian silkmoth outbreak that occurred in 2018–2020 and covered 42 thousand ha in the Irbey region of the Krasnoyarsk Krai. Imagery from the Sentinel-2/MSI sensor was used to calculate a number of spectral indices for images received before and after the outbreak. Field study data were used to create regression models relating the index values to the percentage of dead trees. A number of spectral indices, such as NDVI, dNDVI, NBR, dNBR, NDMI, EVI, and TCG, were used. As a result, spectral indices based on the data from NIR/SWIR bands (NBR, NDMI, dNBR) demonstrated the best correlations with field-measured tree mortality. Therefore, these indices may be used to accurately estimate the percentage of dead trees by remote sensing data. The best was the NBR index with an R2 equal to 0.87, and the lowest RMSE and MAE errors. Consequently, Sentinel-2 imagery can be successfully used for tree mortality assessment over large inaccessible areas disturbed by Siberian silkmoth outbreaks at a relatively low cost.

Short-interval, high-severity wildfires cause declines in soil seed bank diversity in montane forests of south-eastern Australia

Wildfires in forested ecosystems are increasing in severity and extent. The adaptations many plants have acquired in response to their natural fire regime may not be sufficient to allow some species to persist. This could impact the forest understorey and its seed bank, which are vital reservoirs of biodiversity, and forest resilience in the face of global change. We present a case study of the montane forests of south-eastern Australia, an area subjected to an increase in frequency and severity of fires. We utilise field surveys and a soil seed bank germination study to investigate if short-interval, high-severity wildfires affect the understorey diversity in montane forests, and if the extant vegetation and the soil seed bank exhibit contrasting responses. We consider species diversity and plant functional traits to explore plant diversity in long unburned sites, and sites with one, two or three short-interval, high-severity fires in the past 25 years. With increasing fire frequency, we found a decrease in total species richness, Shannon’s diversity, and the richness of resprouters in the soil seed bank, contrasting a lack of response in the extant vegetation. Increased fire frequency shifted the species composition and the frequency of plant functional groups of both extant vegetation and soil seed bank towards a decrease in clonal resprouters and increase in grasses and other upright herbs. The frequency of wind-dispersed perennials and short-lived seeders and exotics increased sharply following single high severity burn, particularly in the soil seed bank, and remained elevated relative to long unburnt with subsequent fire. The combined species (extant vegetation plus soil seed bank) pool mirrored shifts in the frequency of functional groups in extant vegetation and soil seed bank. These findings highlight the importance of considering the soil seed bank when examining the effects of fire on fire-prone forests. Although a lack of response in the extant vegetation may be a buffering effect of the soil seed bank, the shift in the frequency of plant functional groups in the combined species pool suggests this cannot be maintained indefinitely. The increase in frequency and abundance of species characteristic of early successional states has implications for increased flammability and potential positive feedbacks between past fire and future fire, especially in a warming and drying climate. These shifts were independent of the fire response strategy of eucalypt canopy species raising significant questions of whether artificial re-seeding programs should extend beyond the current focus on obligate seeding forests and an obligate seeding tree.

Investigation of the post-blast fire performance of RC members

An explosion or blast can trigger a subsequent fire in the building structure. In the case of reinforced concrete (RC) structures, blast loading can result in relatively large residual deformations and locked-in stresses in the affected members prior to fire exposure. Such residual deformations and locked-in stresses can have a detrimental effect on the subsequent fire performance of RC members. Accordingly, this paper presents results from a numerical study investigating the post-blast fire (PBF) performance of isolated RC columns. A simplified numerical model was developed to implement the integrated environment for modeling the interaction between blast and PBF scenarios without employing complex user-defined subroutines in ABAQUS. The developed FE model was validated against the experimental blast and fire tests. The RC column was subjected to blast loads of distinct scaled distances (Z) simulating the far-field and near-field scenarios. Further, the blast-damaged columns were exposed to a standard fire and evaluated the PBF performance. Results indicated that the fire resistance period (FRP) of RC columns is significantly reduced by prior blast damage, with reductions ranging from 0.8 % to 72 % as Z decreases from 2 to 0.8 m/kg1/3. Consequently, to mitigate these detrimental blast effects and ensure adequate PBF resistance, a transverse reinforcement with a diamond configuration in the plastified region of the RC column is recommended. Furthermore, the study explores the impact of axial load levels on RC column performance under PBF scenarios. It's observed that an increase in axial load levels beyond 25 % of the critical axial load-bearing capacity results in a 100 % reduction in the post-blast FRP of the RC columns. Additionally, Pressure-Impulse (P-I) diagrams are developed examining the blast cases that yield specific post-blast FRP for the RC columns. Notably, the diamond configuration demonstrates superior blast resistance for the same post-blast FRP, as evidenced by the P-I diagrams.

Methodology for probabilistic tsunami-triggered oil spill fire hazard assessment based on Natech cascading disaster modeling

A novel modeling methodology is presented for cascading disasters triggered by tsunami hazards considering uncertainties. The proposed methodology focuses on tsunami-triggered oil spills and subsequent fires, a type of natural hazard-triggered technological (Natech) event. The methodology numerically simulates the time-varying behavior of tsunami-triggered oil spill fires for numerous stochastically generated scenarios and performs a probabilistic mapping of the maximum radiative heat flux as a quantitative measure of the fire hazard. To enable these assessments, probabilistic tsunami hazard assessments are extended to include the tsunami-induced movement of oil storage tanks, resulting oil spills, tsunami-driven oil fire spread, and thermal radiation from fires. The uncertainty of the earthquake fault slip distribution, oil filling level of storage tanks, and fire starting time and position is incorporated into the new assessments. To demonstrate the methodology, a realistic case study is conducted for a coastal petrochemical industrial park in Japan conditioned on possible offshore moment magnitude 9.1 earthquakes. Contrary to typical tsunami direct impact assessments, the results highlight the cascading effects of tsunamis and large variability in key output variables concerning oil spills and fires. This indicates that the methodology is useful for deepening stakeholders’ understanding of tsunami-triggered cascading disasters and improving risk reduction plans.

Enhancing the integrity of a buried gas pipelines: Investigating ruptures, explosions, and strengthening solutions

The present paper presents findings from a case study of a buried gas pipeline that ruptured, causing a gas cloud explosion and subsequent fire. The study aimed to identify the incident's cause and improve the pipeline's strength under specific conditions. The study measured the pipe's actual wall thickness and conducted stress analysis using analytical and finite element methods to assess its integrity under corrosion. It evaluated if the 20-inch pipeline near road crossings could withstand external forces.In conclusion, the research underscores the importance of accurately assessing the structural integrity of buried pipelines, especially under conditions of corrosion. It highlights the utility of finite element analysis in providing a more precise understanding of stress distribution and can aid in designing pipelines that are better equipped to withstand various external pressures.The investigation illustrates the importance of increasing the strength of buried natural gas pipelines, in the crossing road area and, for this purpose, it was proposed (in terms of novelty associated with the study) a solution consisting in introduction of the pipeline in protective sleeves fitted with spacer rings.

Rapid fuel recovery after stand-replacing fire in closed-cone pine forests and implications for short-interval severe reburns

Accelerating disturbance activity under a warming climate increases the potential for multiple disturbances to overlap and produce compound effects that erode ecosystem resilience — the capacity to experience disturbance without transitioning to an alternative state. A key concern is the potential for amplifying or attenuating feedbacks via interactions among successive, linked disturbance events. Following severe wildfires, fuel limitation is a negative feedback that may reduce the likelihood of subsequent fire. However, the duration of, and pre-fire vegetation effects on fuel limitation remain uncertain. To address this knowledge gap, we characterized fuel profiles over a 35-year post-fire chronosequence in California closed-cone pine forests, a system with stand dynamics comparable to stand-replacing fire regimes in other temperate and boreal conifer forests with much longer fire return intervals. We used this system to ask: 1) How do fuel profiles change with time since recent stand-replacing fire? 2) How do trajectories of fuel profiles differ between forests established from different pre-fire vegetation legacies — specifically areas that were forest vs. non-forest pre-fire? We also assessed fuel profiles that supported stand-replacing fire during a large (>90,000 ha) wildfire that burned through our study area shortly after data collection and compared with fuel profiles across the chronosequence. Overall, live and dead surface fuels accumulated quickly, reaching levels comparable to those capable of supporting severe fire after 10–15 years. Canopy fuels peaked at 20 years post-fire but were at levels comparable to those capable of supporting severe fire from 15 years onwards. Pre-fire vegetation legacy drove divergence in post-fire dead surface fuel trajectories, but effects on live surface and canopy fuels were minor. Fuel profiles in California closed-cone pine forests can support subsequent severe fire within 10 years, a fraction of the historical minimum interval between stand-replacing fires (≥30 years) that supports robust post-fire regeneration, but potential for severe fire remains lower for an extended period in areas where pre-fire vegetation was non-forest. Our findings show that the negative feedback of fuel limitation disappears quickly following fire, suggesting that these systems are vulnerable to short-interval severe reburns that could erode forest resilience.