Article

Power line failures and catastrophic wildfires under extreme weather conditions

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Abstract

Catastrophic wildland fires have resulted under extreme wind conditions due to power line system failures. Under conditions of "extreme fire weather", multiple ignitions due to power lines over a broad geographic area can occur under conditions promoting explosive fire growth. Such instances have been observed in the US state of California in 2007, and several times in recent Australian history - most notably the lethal Black Saturday fires of 2009. Ignitions can occur from a variety of failure modes in the huge array of components making up distribution and transmission networks and their neighboring environment. These failures fall into two general categories however: elastic extension of either the conductors or surrounding objects (such as tree limbs) causing electrical contact and arcing, and fatigue failures under high strain conditions affecting system components (conductors, poles, crossarms) or surrounding objects (trees). Both failure classes show a strong dependence on increasing wind speed. Case studies will be shown demonstrating both of these categories. Greatly compounding these physical wind dependencies is the expectation that failure probability will increase sharply with wind speed in an extreme value statistical dependency, such as a reverse Weibull distribution. Outage data from electric distribution systems is shown to demonstrate a very strong increase with wind speed suggesting that outage data from normal operation of an electrical grid may be used to gauge system vulnerability to extreme fire weather conditions. These results also underline the importance of having appropriate design requirements and contingency plans to account for reasonably foreseeable catastrophic weather conditions. Mitigation measures being discussed or implemented by regulators and utilities are discussed.

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... Evaluating all the methods, machine learning-based maximum entropy (MaxEnt) and random forest algorithms are non-parametric methods widely used to estimate the spatial distribution of wildfires using spatial layers and presence locations (Hastie et al. 2009). The MaxEnt model is often referred to as a nonlinear regression model, and in wildfire occurrence mapping, historical wildfires are considered as species distribution to reveal the probability of occurring outside of historical wildfire locations (Parisien and Moritz 2009;Renard et al. 2012;Bar-Massada et al. 2012, 2013De Angelis et al. 2015;Vacchiano et al. 2018;Yago et al. 2019;Bekar et al. 2020;Banerjee 2021;Tariq et al. 2022). Random forest is also a non-parametric model that uses clustering techniques to predict the probability of wildfire occurrence (Archibald et al. 2009;Aldersley et al. 2011;Olivera et al. 2012;Arpaci et al. 2014;Rahmati et al. 2016). ...
... Contact by trees with high-voltage power lines can cause arcing (Mitchell 2013), and winds can move branches to power lines and create sparks. The electric arc can fall to the ground or directly ignite trees. ...
... Most studies used logistic regression-based models (Chuvieco et al. 2009;Martinez et al. 2009) and generalized linear models (Syphard et al. 2008;Martinez et al. 2009;Kwak et al. 2012;Vilar et al. 2016;Costafreda-Aumedes et al. 2017Li et al. 2019) and the random forest algorithm (Archibald et al. 2009;Aldersley et al. 2011;Olivera et al. 2012;Arpaci et al. 2014; Rahmati et al. 2016) due to the presence of nonlinear and nonparametric variables. Another approach is the machine learning algorithms of the MaxEnt method to discover the relationship between variables and ignition possibilities (Parisien and Moritz 2009;Bar-Massada et al. 2012, 2013Renard et al. 2012;De Angelis et al. 2015;Vacchiano et al. 2018;Yago et al. 2019;Bekar et al. 2020;Banerjee, 2021;Tariq et al. 2022). While most studies considered wildfires only as a site of occurrence, this study considered historical wildfires according to their anthropogenic and natural causes to provide a cause-level vulnerability analysis. ...
Article
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Turkey has a high wildfire potential along the Mediterranean coast due to its dense forest cover and mild climate. An average of 250 wildfires occurs every year in Turkey and more than 10,000 hectares of forest cover are destroyed due to natural and human-related reasons. The study area is very sensitive to ignitions caused by lightning, stubble burning, cigarette butts, electric arc from power lines, sabotage and traffic accidents. In addition, 52% of the total historical wildfire causes could not be identified due to intense wildfires occurring at the same time and insufficient cause determination equipment and personnel. Since wildfires destroy forest cover, ecosystem, biodiversity and habitat, they should be spatially evaluated by separating them according to their causes, taking into account the environmental, climatic, topographic and forest structure variables that ignite or trigger the wildfires. In this study, wildfires originating from lightning, stubble burning, cigarette butts and power lines, which are the most common causes of wildfires in the study area, were examined. The MaxEnt method was used to determine the spatial distribution of wildfires in order to determine risk zones for each cause. In the MaxEnt method, wildfires were used as the species distribution and the probability of their occurrence was estimated. Additionally, since the causes of many wildfires are unknown (52% of the total fires), determining the causes will be very important for fire prediction and prevention studies. The highest wildfire occurrence risk areas were calculated as 9.7% for stubble burning, 30.2% for lightning, 4.5% for power lines and 16.9% for cigarette butts. In total, 1266 of the 1714 unknown wildfire causes were identified by the analysis of the cause-based risk zones and these risk zones were updated by including cause-assigned unknown wildfire locations for verification. As a result, the Area Under the ROC Curve (AUC) values were increased for lightning, stubble burning, cigarette butt and power line-induced susceptibility maps.
... The third case of the bushfires of February 2009 in Victoria was also preceded by a drought season, air temperatures above the average (e.g., peak above 45 C in Melbourne), and two heat waves observed over Southeastern Australia from late January to early February [17]. These weather conditions were combined with favorable synoptic patterns characterized by a high-pressure system located in Tasman Sea [18] and low-pressure system located over northern Australia, which had promoted the development of hot air in central Australia and in conjugation with a strong cold front created very strong hot northewesterly winds up to 65 km hour À1 and gusting to 90 km hour À1 in western and central Victoria [17]. These fires affected a wide range of forest types dominated by Eucalyptus regnans with high fuel loads leading to Extreme wildfires and disasters around the world: lessons to be learned exceptional fire intensities (e.g., 100,000 kW m À1 ) [14]. ...
... These fires affected a wide range of forest types dominated by Eucalyptus regnans with high fuel loads leading to Extreme wildfires and disasters around the world: lessons to be learned exceptional fire intensities (e.g., 100,000 kW m À1 ) [14]. During these EWEs, extremely high FFDI (ranging between 120 and 190) had been recorded [10,19], more than 400,000 ha burned [17,18], 173 people had lost their lives, more than 2000 buildings were lost [10,20], and the event had a total cost of more than AUD$3.5 billion [18,19]. ...
... These fires affected a wide range of forest types dominated by Eucalyptus regnans with high fuel loads leading to Extreme wildfires and disasters around the world: lessons to be learned exceptional fire intensities (e.g., 100,000 kW m À1 ) [14]. During these EWEs, extremely high FFDI (ranging between 120 and 190) had been recorded [10,19], more than 400,000 ha burned [17,18], 173 people had lost their lives, more than 2000 buildings were lost [10,20], and the event had a total cost of more than AUD$3.5 billion [18,19]. ...
Chapter
In this chapter, the cases of the extreme wildfires and disasters that occurred in Portugal in 2013 (Picões and Caramulo) and in 2017 (Pedrogão Grande and Central Region), their fire environment, fire propagation, and impacts are described. The Portuguese experience is complemented with other cases that occurred in Greece, Italy, Australia, USA, and Canada, which are described following different fire management approaches. These cases put in evidence the complexity involved in managing these increasingly frequent extreme fire events.
... Wind gusts play a crucial role in wildfire spread, intensity, and spotting [12,29,66], but are not simulated by WRF. As suggested in [67], gusts provide value for understanding extreme winds from an observational and wildfire-focused standpoint based on differing calculation methods. Wind speeds reported at RAWS such as RHWC1 are the average of winds in the 10-min prior to every hour, whereas gusts are the maximum wind recorded in the previous hour. ...
... Wind speeds reported at RAWS such as RHWC1 are the average of winds in the 10-min prior to every hour, whereas gusts are the maximum wind recorded in the previous hour. Previous studies [67][68][69][70] utilized station observations to create a wind gust approximation termed the 'gust factor'. The gust factor (GF) is calculated by dividing the gust speed by the wind speed, and varies between stations due to sampling length and frequency, averaging interval, and instrument mounting height [70]. ...
... The average GF between the time of ignition and the last observed perimeter of that first evening (1500 to 1900 PDT) was 1.38, demonstrating the variability of the GF through the use of different temporal subsets. While GFs have not been extensively analyzed in coastal Santa Barbara, studies on Santa Ana and Diablo winds calculated an average GF of 1.7 [67][68][69]. In this study, the Sherpa and Painted Cave fires were simulated multiple times using no gust factor, a 1.4 GF, and a 1.7 GF. ...
Article
Full-text available
Extreme, downslope mountain winds often generate dangerous wildfire conditions. We used the wildfire spread model Fire Area Simulator (FARSITE) to simulate two wildfires influenced by strong wind events in Santa Barbara, CA. High spatial-resolution imagery for fuel maps and hourly wind downscaled to 100 m were used as model inputs, and sensitivity tests were performed to evaluate the effects of ignition timing and location on fire spread. Additionally, burn area rasters from FARSITE simulations were compared to minimum travel time rasters from FlamMap simulations, a wildfire model similar to FARSITE that holds environmental variables constant. Utilization of two case studies during strong winds revealed that FARSITE was able to successfully reconstruct the spread rate and size of wildfires when spotting was minimal. However, in situations when spotting was an important factor in rapid downslope wildfire spread, both FARSITE and FlamMap were unable to simulate realistic fire perimeters. We show that this is due to inherent limitations in the models themselves, related to the slope-orientation relative to the simulated fire spread, and the dependence of ember launch and land locations. This finding has widespread implications, given the role of spotting in fire progression during extreme wind events.
... As discussed earlier, one of the significant factors that lead to wildfire is extreme weather conditions from climate change, for instance, high winds [10]. High winds speeds, [11] with "gusts of up to 140km/h measured at the Potrero weather station" [12] have the potential to cause conductor slap or breakdown or failing power line equipments [13], [14], [15]. Due to dry vegetation, and low moisture content on the ground can cause fire immediately and leads to wildfires. ...
... The studies in literature explain the following wildfire risks: vegetation issues [16], vegetation uncertainty (related to a tree falling on power lines) [12], conductor clashing during extreme weather conditions [12], the impact of the weak infrastructure of Distribution and Transmission Network [12], congestion of transmission power lines [26] and excessive heating in the system's equipment due to the harmonics and this problem is more frequently seen in the distribution network [28], [15]. In next few sections, we will overview the cause of wildfires from electrical corporations point of view. ...
... The studies in literature explain the following wildfire risks: vegetation issues [16], vegetation uncertainty (related to a tree falling on power lines) [12], conductor clashing during extreme weather conditions [12], the impact of the weak infrastructure of Distribution and Transmission Network [12], congestion of transmission power lines [26] and excessive heating in the system's equipment due to the harmonics and this problem is more frequently seen in the distribution network [28], [15]. In next few sections, we will overview the cause of wildfires from electrical corporations point of view. ...
Preprint
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In the past decade, summer wildfires have become the norm in California, and the United States of America. These wildfires are caused due to variety of reasons. The state collects wildfire funds to help the impacted customers. However, the funds are eligible only under certain conditions and are collected uniformly throughout California. Therefore, the overall idea of this project is to look for quantitative results on how electrical corporations cause wildfires and how they can help to collect the wildfire funds or charge fairly to the customers to maximize the social impact. The research project aims to propose the implication of wildfire risk associated with vegetation, and due to power lines and incorporate that in dollars. Therefore, the project helps to solve the problem of collecting wildfire funds associated with each location and incorporate energy prices to charge their customers according to their wildfire risk related to the location to maximize the social surplus for the society. The thesis findings will help to calculate the risk premium involving wildfire risk associated with the location and incorporate the risk into pricing. The research of this submitted proposal provides the potential contribution towards detecting the utilities associated wildfire risk in the power lines, which can prevent wildfires by controlling the line flows of the system. Ultimately, this proposal goal is a social benefit to save money for the electrical corporations and their customers in California, who pay Wildfire Fund or charge each month 5.85/KWH (in dollars). Therefore, this proposal will propose methods to collect wildfire funds with maximum customer surplus for future generations.
... Total fire bans are declared for days when the maximum forecast FDR has a Severe or higher rating (i.e., GFDI or FFDI ≥ 50). The general incidence of vegetation fires from electrical sources throughout the year is low, typically 1.5-3% of all fires across Victoria (Marxsen, 2016;Mitchell, 2013), 1.6% around Perth, Western Australia (Plucinski, 2014), about 2.2% across Australia (Bryant, 2008) and 1% in California (Mitchell, 2013). However, there has been a general perception as a result of the many inquiries that electrical fires on days of elevated fire danger are much more prevalent and have greater consequences in regard to area burnt and level of destruction than fires from other sources There has been little research investigating the effect of timing and weather on the occurrence of wildfires from specific causes, especially electrical fires. ...
... Total fire bans are declared for days when the maximum forecast FDR has a Severe or higher rating (i.e., GFDI or FFDI ≥ 50). The general incidence of vegetation fires from electrical sources throughout the year is low, typically 1.5-3% of all fires across Victoria (Marxsen, 2016;Mitchell, 2013), 1.6% around Perth, Western Australia (Plucinski, 2014), about 2.2% across Australia (Bryant, 2008) and 1% in California (Mitchell, 2013). However, there has been a general perception as a result of the many inquiries that electrical fires on days of elevated fire danger are much more prevalent and have greater consequences in regard to area burnt and level of destruction than fires from other sources There has been little research investigating the effect of timing and weather on the occurrence of wildfires from specific causes, especially electrical fires. ...
... However, there has been a general perception as a result of the many inquiries that electrical fires on days of elevated fire danger are much more prevalent and have greater consequences in regard to area burnt and level of destruction than fires from other sources There has been little research investigating the effect of timing and weather on the occurrence of wildfires from specific causes, especially electrical fires. Mitchell (2009Mitchell ( , 2013 found that the number of electrical fires increased rapidly with increases in wind speed in southern California and were disproportionately high during periods of dangerous wildfire weather compared to those ignited by other causes. This study also found that electrical fires burned considerably larger areas on average than fires from other ignition sources, and that there is an association between strong winds, powerline faults and rapid fire spread (Mitchell, 2013). ...
Article
Electricity distribution infrastructure causes fewer wildfires than most other sources of ignition. However, these fires have been associated with more severe consequences than those from other causes. This paper examines whether fires caused by faults in electricity distribution infrastructure occur more often during periods of elevated fire danger, thereby increasing their consequence. The occurrence of wildfires caused by electricity distribution infrastructure were compared to those attributed to other causes during periods of elevated fire danger across the State of Victoria, Australia, where historically such fires have had significant impact on lives and assets of value. The results provided strong evidence that fires caused by electrical faults are more prevalent during elevated fire danger conditions and that they burn larger areas than fires ignited by most other causes. As a result the consequences of fires caused by electricity infrastructure are worse than fires from other causes. This knowledge highlights the importance of mitigating ignition-causing faults in the electricity network, particularly on days of elevated fire danger.
... Extreme winds, such as the ones occurring during fall seasons in Southern California, not only increase the risk of power line-related ignitions but also facilitate the propagation of fire. According to the historical data during the period 1960-2009 in Southern California, fires ignited by power lines burn on average ten times the area burnt as a result of fires initiated by other sources [6]. Conductor clashing (phase to phase faults), fall of the line on the ground M. Waseem (phase to ground faults), arcs, and contact with the surrounding vegetation are among the incidents related to power lines that could cause ignitions [7]. ...
... Although low wind speeds will cool off conductors and can benefit dynamic line rating [10], high wind speeds can lead to faults within power lines. According to the analysis of the 11-years outage record data provided by San Diego Gas & Electric (SDG&E), for every 25 km/h increase in the wind gust speed, the outage probability is increased ten times [6]. Higher wind speeds are associated with higher chances of fire ignition. ...
... In contrast, nearly half of the fires (9 out of 20) in October 2007 were initiated by power lines. The difference is because the peak wind speeds during 2007 were 80% higher than those during 2003 [6]. ...
Preprint
Full-text available
This paper presents a surrogate model to quantify the risk of wildfire ignition by individual power lines under extreme weather conditions. Wind speed and wind gust can lead to conductor clashing, which is a cause of igniting disastrous wildfires. The 3D non-linear vibration equations of power lines are employed to generate a dataset that considers physical, structural, and meteorological parameters, including the span of the power line, conductor diameter, wind speed, wind gust, phase clearance, and wind direction. A set of machine learning models is assembled based on these features to generate a score representing the risk of conductor clashing for each power line within a network, quantifying the risk of wildfire ignition. The rendered score represents the chance of the conductor clashing in place of simulating a Runge-Kutta method. A discussion on the impact of various meteorological parameters on power lines under the energization risk is presented. Besides, it is shown how the presented risk measure can be utilized to weigh in the fire safety and service continuity trade-off.
... In addition to evolving utility practices to mitigate wildfire risk, research literature includes an emergence of studies aimed at enhancing power system resilience to atypical catastrophic events such as wildfire [9]- [16]. Various fault and scenarios leading to wildfire ignition are explored in [10], illustrating the statistical correlation between wind speed and fire ignition probability. A statistical characterization between sustained ignition of a dry fuel bed and several influencing parameters including wind speed, fuel moisture content, and arc duration is developed in a laboratory test setting in [11]. ...
... Other studies investigate changing power grid operations driven by severe weather forecasts or knowledge of an approaching wildfire [14]- [16]. While the models in [10]- [16] are vital to understanding the wildfire ignition problem, the literature lacks a comprehensive model that characterizes the sophisticated relationship between the many variables that influence wildfire ignitions. This paper develops a comprehensive analytical framework to assist distribution system operators in understanding and quantifying the impact of factors that drive power-systemrelated wildfire ignitions. ...
... To develop fragility curves for a power distribution component, a relationship is characterized between fault probability and a set of influencing variables, most commonly wind speed. In order to fully characterize this relationship, historical line fault data as well as data describing the influencing variables must be obtained and matched spatio-temporally with historical faults [10]. Through routine inspections and asset tracking, utilities compile data that would provide additional insight into fault and ignition probabilities. ...
Article
Full-text available
This paper proposes a modeling approach for characterizing the probability of wildfire ignition caused by faults on power distribution systems. The proposed model serves as a starting point in research literature to illustrate, from an analytical perspective, the many factors that influence wildfire ignitions in power distribution systems. This paper presents the series of events that leads to power-system-related wildfire ignitions, and characterizes the wildfire ignition probability as a combination of the probability that a fault occurs along a power distribution line segment, and the probability that the fault results in the sustained ignition of a vegetation fuel bed surrounding the line. The proposed model integrates a variety of data including environmental conditions, power system protection settings, and power system line flows. A case study is performed on a test 33- bus distribution system using observed historical weather data from a high-threat fire district in California. The California case study is utilized to investigate the effects of three primary factors (wind speed, line congestion, and protection settings) on wildfire ignition probability.
... Catastrophic bushfires have resulted under elevated fire weather conditions due to power transmission system failures, under these conditions multiple ignitions due to power infrastructure over a broad geographic area can stretch fire suppression resources and simultaneously threaten multiple communities Such instances have been observed in the US state of California in 2007, and several times in recent Australian history -most notably the lethal Black Saturday fires of 2009 (Mitchell 2013). A common response from governments and utility providers has been to embark on optimised electricity network asset improvement and replacement programs where the aim is for the cost-effective reduction of power line sparked ignitions in bushfire hazard areas under elevated fire weather conditions. ...
... These failures fall into two general categories; those caused by a contact event though increased proximity of either the conductors or surrounding objects (such as tree limbs) causing electrical contact and asset failures through arcing, and fatigue under high strain conditions affecting system components (conductors, poles, cross arms) or surrounding objects (trees). Both failure classes show a strong dependence on increasing wind speed (Mitchell 2013) and or temperatures (line sagging). Power distribution pole networks are also vulnerable to a changing climate. ...
Conference Paper
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Western Power is a Western Australian State Government owned power network and energy corporation. In 2013, an external review commissioned by Western Power, recommended the development of an improved bushfire risk map for the network based on the consequences of potential network bushfire ignitions. In response to the review Western Power entered into a joint collaboration with the Department of Fire and Emergency Services (DFES) and Landgate to develop a multiple ignition point based bushfire risk analysis product suitable for use on the power network across the south west of Western Australia. The objective of this project is to assist Western Power in prioritising their asset renewal and maintenance budget to ensure they’ve addressed sites with the highest potential consequences, realising better public safety out-comes. The utilisation of the fire spread simulator system Aurora, to model the consequences of a bushfire ignition from power poles and wires has been investigated to provide this intelligence. Western Power maintains approximately 800,000 power poles within the south west of Western Australia. The development of an appropriate methodology to provide the required intelligence for the prioritisation of appropriate asset renewal and maintenance implementation programs in response to the risk of bushfire ignition, has proven to be challenging. Aurora is a web-based bushfire spread prediction system that simulates the probable direction, intensity and rate of bushfire spread. The simulator considers ignition location, vegetation, time of last burn, fuel accumulation models, forecasted weather, drought factor, grassland curing and slope to calculate fire behaviour and spread. For this project, the simulator architecture uses 99.5th percentile Forest Fire Danger Index (FFDI) weather conditions for each of the 8 cardinal wind directions to produce 6 million fire spread simulations. These simulations together with a building location dataset are used to estimate asset numbers that could potentially be impacted by a fire running for one hour, from each power pole. Using this methodology maintenance can be prioritised for individual power poles based on the potential impact of a bushfire caused by a fault. The successful completion of this project will result in a well-developed methodology, Information Communication and Technology (ICT) system infrastructure and potential consequence datasets with the potential to utilise multiple activities and assets as potential ignition sources, therefore providing DFES with enhanced evidence-based datasets to support strategic decision making for early community warning and preparedness.
... Rather, utilities can seek wooden poles with higher top circumference for greater mechanical strength [39]. Distribution line failure is often considered as a ''weakest link'' failure, so upgrading several consecutive poles (especially adjacent to those that carry automated switches and reclosers) is a commonplace hardening strategy [39], [40]. Additionally, spacer cables can help to reduce tree impact related outages [39]. ...
... Namely, mechanical elements such as clamps and line splices are commonly carefully tracked, and plans are developed in advance to replace worn, stressed, or fatiguing infrastructure. Although structural requirements for distribution poles and conductors are rated by the National Electrical Safety Code [43], and are designed to withstand storm level wind speeds, a vast majority of failures occur at wind speeds much lower than this critical wind speed [40]. This relationship implies that, while failure probability is inextricably related to wind speed, distribution system faults can occur independent of high wind speeds, and that deterioration of structural elements may contribute to failure rates of power lines even at low wind speeds. ...
Article
Full-text available
Managing the risk of wildfires has been arguably the biggest recent challenge of electric utilities with infrastructure located in the wildland-urban interface. Utilities are deploying solutions for wildfire risk mitigation, such as public safety power shutoffs, which are counter-intuitive from a reliability-centric operation paradigm. This article presents an overview of the challenges, implications, and potential strategies for wildfire risk mitigation in power systems, and introduces the vision for a wildfire-resilient power system. The wildfire risk management strategies presented in this article range from fault prevention methods such as structural hardening, vegetation management and implementing advanced protection systems, to arc-suppression and ignition prevention methods. This article also identifies relevant research opportunities associated with implementing wildfire mitigation techniques on power systems. INDEX TERMS Wildfire risk mitigation, power grid resilience, proactive operation, wildfire-resilient power grid.
... Another negative effect that has only ever been poorly studied is the impact of the wildfires caused by electrocuted animals. Although power lines usually cause wildfires when there is electrical contact with nearby trees (Mitchell, 2013), wildfires can also occur when an electrocuted animal begins to burn and falls to the ground (Kagan, 2016). Despite significant negative consequences including the loss of human life in cases such as the 2014 Valparaíso wildfire in Chile (Vargas, 2016), fauna-mediated wildfires are very poorly documented in the literature. ...
... Cruz et al., 2012). In the former case, this is important because power-line fires are concentrated in autumn and are associated with strong winds, which create situations of extreme fire behaviour (Mitchell, 2013;Syphard and Keeley, 2015). ...
Article
The interaction between wildlife and power lines has collateral effects that include wildfires and Carbon Dioxide (CO2) emissions. However, currently available information is scarce and so new approaches are needed to increase our understanding of this issue. Here, we present the first analysis of wildfires and their incidence as a result of this interaction in Spain during the period 2000-2012. Amongst the 2,788 Power-Line Mediated Wildfires (PLMW recorded) during this period, 30 records of Fauna Mediated Wildfires (FMW) were found, with an average affected vegetation cover of 9.06 ha. Our findings suggest that no significant differences were observed between the amount of affected surface area due to fauna mediated wildfires and power-line mediated wildfires. In both cases, a space-grouping trend was observed. In terms of changing trends over time, after the first incident detected in 2005, the number of incidents increased until 2008, year in which the percentage of wildfires caused by wildlife stabilized at approximately 2.4% of all power-line-induced wildfires. Population density and road abundance were variables that better explained PLMW whereas for FMW, the models that included land use and raptor abundance. In the multivariate model, FMW emergence was positively related with population density, percentage of grazing areas and Natura 2000 cover, and predatory abundance; and negatively with the percentage of forested area. No significant differences were observed between the species of birds that caused wildfires and the species of ringed birds killed by electrocution. The economic and environmental impact due to necessary repairs, the loss of biodiversity and CO2 emissions represent an estimated net value of €7.6-12.4 M for the period 2000-2012, which indicates the importance of the economic and environmental costs associated with wildfires.
... The researcher strongly recommends that the present survey [39][40][41][42][43][44][45][46][47][48][49] to the present and future researchers, the thermal image inspection of power lines. This inspecting facility are indented in the inspection methods to find a possible electrical difficulty and it is utilizing with different parameters or different natural calamities. ...
... Such causes may be more sensitive to the specific ambient conditions and have attracted considerable theoretical, experimental and statistical work, e.g. smoking (Countryman 1983;Kohyo et al. 2003;Butry et al. 2014), powerline arcs (Mitchell 2013;Miller et al. 2017) or rifle bullets (Finney and McAllister 2016). ...
Article
Several large Swedish wildfires during recent decades were caused by forestry machinery in operation, fires for which there is still no characterisation. We combined 18 years of data on dispatches, weather and fire danger and interviewed forestry workers to understand the spatial, temporal and weather distributions of these fires, and their underlying mechanisms. We estimate the average annual number of ignitions from forestry machinery in Sweden at 330–480 (2.0±0.4 ignitions per 1000ha clear-felling) of which 34.5 led to firefighter dispatches, constituting 2.2% of all forest fire dispatches and 40% of area burnt. Soil scarification causes the most ignitions and the main mechanism is likely high-inertia contact between discs and large stones, causing sparks igniting dry humus or moss, countering reports suggesting that such metal fragments cannot fulfil ignition requirements. We found a spatial relationship between forestry machine ignitions and abundance of large stones, represented by a Boulder Index generated from a nationwide dataset. Further, 75% of the dispatches occurred on days with relative humidity <45%, Duff Moisture Code (Canadian system) >26 and Fire Weather Index >12. 75% of the area burned when Fire Weather Index was >20. Results suggest machine-caused forest fires can be largely avoided by cancelling operations in stony terrain during high-risk weather.
... Another measure that could prevent powerline-ignited fires would be to place powerlines underground. Although such measures are unpopular with utility companies, powerline-ignited fires often contribute to some of the most devastating human losses from wildfire (like those in San Diego County in 2007 and in northern California in 2017, and this relationship has been established in other parts of the world as well (Mitchell 2013). ...
... Our findings suggest winds may be particularly important for human-caused fires that often occur in areas where bottom-up factors such as suppression resources, response times and greater landscape fragmentation would otherwise tend to reduce large fire potential ). In addition to promoting fire propagation, strong winds can also facilitate human-caused ignitions as in the case of fallen powerlines (Mitchell 2013;Collins et al. 2016), which account for a large proportion of the overall burned area in some regions where winds have been implicated in fire activity (Syphard and Keeley 2015). ...
Article
Large wildfires (>40 ha) account for the majority of burned area across the contiguous United States (US) and appropriate substantial suppression resources. A variety of environmental and social factors influence wildfire growth and whether a fire overcomes initial attack efforts and becomes a large wildfire. However, little is known about how these factors differ between lightning-caused and human-caused wildfires. This study examines differences in temperature, vapour pressure deficit, fuel moisture and wind speed for large and small lightning-and human-caused wildfires during the initial days of fire activity at ecoregion scales across the US. Large fires of both human and lightning origin occurred coincident with above-normal temperature and vapour pressure deficit and below-normal 100-hour dead fuel moisture compared with small fires. Large human-caused wildfires occurred, on average, coincident with higher wind speeds than small human-caused wildfires and large lightning-caused wildfires. These results suggest the importance of winds in driving rapid fire growth that can allow fires to overcome many of the factors that typically inhibit large human-caused fires. Additionally, such findings highlight the interplay between human activity and meteorological conditions and the importance of incorporating winds in modelling large-fire risk in human-dominated landscapes.
... More people do not just mean more exposure to hazards, they also mean more ignition sourcescooking fires, cool burns, machinery -grinders, welders, slashers -power lines (Syphard and Keeley, 2015) and arson (Cozens and Christensen, 2011). The electricity network, strung up like spiders webs, tends to fail under the most extreme fire conditions of high temperatures and high winds (Mitchell, 2013) Ranges to the east of Melbourne on the grounds that dwellings should never be allowed to be constructed in such a potentially dangerous, bushfire-prone area" (Bond and Mercer, 2014 p8). In contrast, following Black Saturday, the Victorian Government offered a voluntary buy back of blocks in fire prone areas, but this has had limited and patchy uptake and with growth in peri-urban populations many people now live in similarly dangerous bushland areas. ...
Chapter
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A range of socio-economic factors determines vulnerability to bushfire disasters. Land use or spatial planning plays key roles in the knowing and governing of landscapes, shaping the relational dynamics of bushfires, people and place. As a determinant of peoples’ exposure to hazards, spatial planning is central to consideration of disaster mitigation and disaster justice. Drawing on experience from Victoria, Australia—a region of intensely destructive wildfires—this chapter explores the opportunities and challenges involved in using integrated planning to mitigate bushfires. With climate change increasing bushfire impacts and intensities, knowledge of bushfires needs to be systemically converted to plans, policies and practices. Learning to live in highly flammable landscapes requires adaptive policies and deeper respect for the co-produced nature of the country and its bushfires.
... Land use, water surfaces, power lines and road networks criteria are involved in environmental parameters which increase ignition risk. Especially high voltage power lines tend to ignition and the zones under power lines may be identified as highly fire potential (Mitchell, 2013). Land use criteria separate industrial, urban, forestry and water surface zones. ...
Conference Paper
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Determining the most suitable apiary locations have vital importance to increase the yield and the productivity, besides determining risk zones also important to sustain productivity and prevent economic loss. Considering sloping topography and intensive forest land cover of Muğla province, beekeeper locations are more likely to be exposed to forest fires and flood hazards. Forest fires and flood hazards can cause great damages to bee colonies and even loss of colonies, hives and bee products. Thus, predicting risk areas and possible hazard locations can prevent big damages to beekeepers. Especially probable forest fire locations can be predicted considering the susceptible rate of each tree type to fire. For flood hazards, probable maximum water level increasing line near water resources and rivers can be predicted and beekeepers can be located to higher altitude from this level. For the purpose of determining risk zones for apiary locations, decision supports systems should be used including spatial analysis techniques and Geographical Information Systems (GIS). In this study, GIS and Multi Criteria Decision Analysis (MCDA) techniques are used to determine probable forest fire risk and flood hazard areas to protect apiary locations in Muğla, Turkey. Both fire and flood risk mapping require including criteria in the field of meteorological, environmental, topographical and socio-economic perspectives. Probable forest fire risk zones are calculated considering slope, aspect, elevation, water resources, land use, settlements, roads, wind, temperature, power lines and vulnerability of tree types. Probable flood hazard zones are calculated considering slope, aspect, elevation, water resources, land use, settlements, roads, precipitation, soil structure and stream order data. All the criteria are included in Analytical Hierarchy Process to be able to calculate the importance of all criteria and susceptibility maps are generated. On the other hand, probable water flow areas and lines are detected via hydrology analyses which are involved in GIS. Reliability and applicability of susceptibility maps are examined by intersecting forest fire and flood hazard data in the past
... For example, an inquiry report following the 2009 Black Saturday bushfires estimated that 200 fires per year are started in Victoria due to the ageing electricity grid (Teague et al., 2010). Electric grid fires are primarily due to elastic extension and fatigue failures, and are made increasingly worse by high wind speeds (Mitchell, 2013). A 2017 study found that fires sparked by electricity failures are more prevalent during elevated fire risk and tend to tend to burn larger, making them worse than fires due to other causes (Miller et al., 2017). ...
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Abstract. Disastrous bushfires during the last months of 2019 and January 2020 affected Australia, raising the question to what extent the risk of these fires was exacerbated by anthropogenic climate change. To answer the question for southeastern Australia, where fires were particularly severe, affecting people and ecosystems, we use a physically-based index of fire weather, the Fire Weather Index, long-term observations of heat and drought, and eleven large ensembles of state-of-the-art climate models. In agreement with previous analyses we find that heat extremes have become more likely by at least a factor two due to the long-term warming trend. However, current climate models overestimate variability and tend to underestimate the long-term trend in these extremes, so the true change in the likelihood of extreme heat could be larger. We do not find an attributable trend in either extreme annual drought or the driest month of the fire season September–February. The observations, however, show a weak drying trend in the annual mean. Finally, we find large trends in the Fire Weather Index in the ERA5 reanalysis, and a smaller but significant increase by at least 30 % in the models. The trend is mainly driven by the increase of temperature extremes and hence also likely underestimated. For the 2019/20 season more than half of the July–December drought was driven by record excursions of the Indian Ocean dipole and Southern Annular Mode. These factors are included in the analysis. The study reveals the complexity of the 2019/20 bushfire event, with some, but not all drivers showing an imprint of anthropogenic climate change.
... In particular fires caused by clashing conductors have the potential to grow more rapidly than other fires because the conductor clashing is typically caused by high winds which causes the fire to spread faster [7]. In addition, research shows that fires caused by clashing conductors typically occur when the fire danger is higher from other factors such as ambient temperature, weather patterns, humidity, fuel moisture content, etc., not just high winds [8]. ...
Article
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The ignition of combustible material by contact with hot metal particles is an important pathway by which wildland and urban spot fires are started. This work examines how fuel characteristics such as density, morphology and chemical composition effect the ability of the fuel to be ignited by a hot metal particle. Fuels were prepared out of three materials: alpha-cellulose, a barley/wheat/oat grass blend, and pine needles. Each material was prepared as a powder and as larger, long pieces: strips of cellulose paper, loose grass, and pine needles. These fuels are representative of thermal insulation (cellulose strips), dry grasses (grass blend), forest litter (pine needles) and duff (powders). Aluminum particles ranging from 2 mm to 8 mm in diameter heated to temperatures between 575°C and 1100°C were dropped onto these fuels. The particle temperature required for ignition becomes higher as the particle size decreased. The results show that the required temperatures for ignition of powders were lower, with this trend particularly pronounced for the alpha-cellulose fuels. The biomass fuels required higher temperature particles to ignite, indicating that the presence of other ligno-cellulosic materials make ignition more difficult.
... Suas estimativas probabilísticas são imprescindíveis para o planejamento e Caracterização das ocorrências de precipitação de granizo e seus impactos socioeconômicos no estado do Paraná desenvolvimento das atividades sujeitas a seus efeitos adversos, especialmente as edificações e agricultura. Diversos estudos são realizados em todo o mundo para identificar a frequência e forma de mitigar os impactos das precipitações de granizo (Sura, 2011;Mitchell, 2013;Jahn, 2015; Precipitação de granizo é um evento extremo caracterizado por precipitação de água em estado sólido, com alta capacidade destrutiva tanto no meio rural quanto no urbano, gerando prejuízos. O Estado do Paraná, localizado predominantemente em zona subtropical e de transição climática, é frequentemente atingido por esse fenômeno. ...
Article
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Precipitação de granizo é um evento extremo caracterizado por precipitação de água em estado sólido, com alta capacidade destrutiva tanto no meio rural quanto no urbano, gerando prejuízos. O Estado do Paraná, localizado predominantemente em zona subtropical e de transição climática, é frequentemente atingido por esse fenômeno. O objetivo deste trabalho foi caracterizar as ocorrências de granizo e os impactos no Estado do Paraná, correlacionando a formação deste evento danoso para as práticas e atividades humanas com os elementos e fatores climáticos (precipitação pluviométrica, temperatura e a hipsometria). Foram utilizadas quatro fontes distintas de dados: estações agrometeorológicas, jornais regionais, imagens de satélite e relatórios de ocorrências, danos e situações de emergência da Defesa Civil. Verificou-se que todo o Estado é afetado pelos eventos e as regiões mais propícias são Centro-sul, Oeste, Sul e Sudoeste, as quais também são as regiões com maiores números de casas danificadas e pessoas afetadas. A altitude, a latitude e o deslocamento preferencial dos sistemas meteorológicos foram elementos fundamentais na interpretação dos mapas de espacialização das ocorrências, uma vez que, os municípios mais ao Sul do Estado e com altitudes acima de 700 m e/ou rápida ascensão altimétrica se mostraram mais propícios à incidência de granizo. Ao todo foram 950.000 pessoas com algum tipo de dano, 41.234 casas danificadas e 375 destruídas em 17 anos de análise.
... A large number of the most damaging wildfires in California have been attributed to power lines damaged by strong winds [1,2]. Figure 1a shows significant increase in the number of these type of wildfires in recent years [3]. ...
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Damages caused by wildfires in California due to transmission line failures have increased significantly in recent years. Curtailment of electric service in areas under fire threat has been implemented to avoid these wildfires. Results from this research indicated that 24% of California’s cities are at risk of wildfire, while 52% are at risk of blackout. These blackouts have resulted in significant financial losses and risk to life and health. Undergrounding current transmission lines has been proposed as a long-term solution. However, undergrounding lines would take decades to complete and increase average monthly electric bills from $80 to $260. This research investigated shortening the length of the electricity supply chain, supplying affected communities with onshore and offshore wind energy. Results showed good wind energy potential in locations near affected cities. Distance analyses revealed that more than two hundred cities (population 5.5 million) can be served by existing wind farms located at less than 50 km. Future offshore wind turbines could generate high power output (capacity factor >50% for significant periods). An analysis of diverse locations along California’s coast indicated that just one offshore wind farm could serve more than a hundred cities with cumulative population larger than one million.
... It happens frequently during summer seasons in some countries. Extreme wind velocity and dry wind are the main factors that contribute to explosive fire growth, causing power line failures in California and Australia, as reported in [92]. Wildfire incidences may be induced by natural phenomena or human activities. ...
Article
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The overhead transmission line system is one of the methods of transmitting electrical energy at a high voltage from one point to another, especially over long distances. The demand for electrical energy is increasing due to the increase in the world population, the evolution of transport technology, and economic expansion, thereby resulting in overloading to the overhead line (OHL) system. In building new infrastructure for transmission lines, several issues need to be addressed. Thus, optimizing existing power by increasing the ampacity of power line is a practical solution to meet energy demand issues. During long-term operation, the temperature of OHL conductors may increase beyond their rated temperature, which is typically 75 °C for conventional conductors such as aluminum-conductor steel-reinforced cable. This condition is defined as thermal stress, which results in lower sag vertical clearance, tensile loss, elongation and creep, and reduced life span of the conductors. This condition must be avoided to ensure that the line is not permanently elongated, which can disrupt the vertical ground clearance, and to expand the conductor’s life. Other factors such as lightning, wildfire, aging, and degradation of the conductor can also cause thermal stress on the conductors and have thermal effects on the conductor’s performance. Therefore, unwanted thermal stress needs to be examined and identified by monitoring the thermal effect and behavior of the lines. This paper presents the state of the art in monitoring technologies that can be used to identify thermal stress on OHL conductors, including the issues and challenges in monitoring. At the end of this paper, a few suggestions are included to address the occurrence and assessment of thermal stress in lines. Ultimately, this work may provide complete information to researchers and maintenance engineers to enable them to make better decisions on condition monitoring, operation, and maintenance of the system.
... The proportion of deliberately ignited wildfires that destroyed houses is similar to the proportion of deliberately ignited wildfires where no houses were destroyed but powerline-and lightning-caused fires are disproportionately higher for wildfires that destroyed houses (Fig 6). While there are no similar studies investigating ignition causes and destroyed houses, the proportion of powerline-caused wildfires substantially increases in Southern California under high wind conditions and several large destructive wildfires in October 2007 were ignited by powerlines [57]. These results suggest that to decrease the number of wildfires that destroy houses, efforts should be focussed on improving the safety of powerlines, reducing the fire spread of lightning-caused wildfires and reducing the number of deliberate wildfire ignitions. ...
Article
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Many houses are at risk of being destroyed by wildfires. While previous studies have improved our understanding of how, when and why houses are destroyed by wildfires, little attention has been given to how these fires started. We compiled a dataset of wildfires that destroyed houses in New South Wales and Victoria and, by comparing against wildfires where no houses were destroyed, investigated the relationship between the distribution of ignition causes for wildfires that did and did not destroy houses. Powerlines, lightning and deliberate ignitions are the main causes of wildfires that destroyed houses. Powerlines were 6 times more common in the wildfires that destroyed houses data than in the wildfires where no houses were destroyed data and lightning was 2 times more common. For deliberate- and powerline-caused wildfires, temperature, wind speed, and forest fire danger index were all significantly higher and relative humidity significantly lower (P < 0.05) on the day of ignition for wildfires that destroyed houses compared with wildfires where no houses were destroyed. For all powerline-caused wildfires the first house destroyed always occurred on the day of ignition. In contrast, the first house destroyed was after the day of ignition for 78% of lightning-caused wildfires. Lightning-caused wildfires that destroyed houses were significantly larger (P < 0.001) in area than human-caused wildfires that destroyed houses. Our results suggest that targeting fire prevention strategies around ignition causes, such as improving powerline safety and targeted arson reduction programmes, and reducing fire spread may decrease the number of wildfires that destroy houses.
... In all the criteria except the river, the chance of ignition increases while getting near to objects. Contact of high-voltage power lines with trees can cause arcing which increases the ignition potential (Mitchell, 2013). Similarly, areas near roads are quite fireprone due to the matches and cigarettes carelessly thrown away by people (Suryabhagavan et al. 2016). ...
Article
Turkey has a high forest fire potential along the Aegean and Mediterranean coasts, related to climate and extremely sensitive forests. In Turkey over 10,000-ha forest area has been destroyed every year and inevitable damage has been revealed. Forest fires not only destroy forest areas, but also cause damage to ecosystems, habitats and especially human lives. Because Muğla province has 90% of total pine honey production in the world and a high potential forest fire occurrence rate, sustainability of ecosystems, productivity and economic income require determining forest fire susceptibility zones. Generating forest fire susceptibility zones is a complex study which requires considering environmental, forestry, topographic, economic, and meteorological parameters within a decision support platform. At this point, Geographical Information System (GIS) aided Multi-Criteria Decision Analysis (MCDA) techniques can provide sufficient and effective solutions for fire susceptibility mapping due to the comparable and scalable structure of the criteria that are used to determine the susceptibility map when deciding. In this study, the weight of each criterion is calculated via the Analytical Hierarchy Process (AHP). Then, TOPSIS and VIKOR methods were used to generate forest fire susceptibility maps in Muğla province. The results indicated that 1659.44 ha (13%) and 3952.14 ha (31%) of the study area were assigned as highly prone to forest fire according to the TOPSIS and VIKOR calculations respectively, and an 81% correlation coefficient was calculated between methods. The reliabilities of the maps were verified with 1454 forest fire locations. Considering the respective 89.54%, 86.94% and 88.99% accuracy rate of VIKOR, TOPSIS and AHP susceptibility maps, all the methods could be used in forest fire susceptibility map generation which has comprehensive decision making process.
... Ansari, B et al [6] mainly constructed a model which can simulate the impact of wildfires on different line grade. In addition, the influence of wind on the tripping of transmission lines is emphasized, including the relationship between wind speed and power interruption [7], and the convective heat transfer cooling effect of wind on transmission lines [8]. Regarding the prevention of ...
Article
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The serious consequences of transmission lines tripping fault induced by wildfires ( TLTFIW ) urges scholars to pay more attention to the safe operation of transmission lines. To illustrate the evolution process of TLTFIW and quantitatively evaluate the occurrence probability of subsequent events, an algorithm used for TLTFIW is proposed by using ETA, FTA and fuzzy number theory in this paper. The evolution process of TLTFIW is simulated according to ETA, which is divided into six stage including wildfires occurring, early wildfires early-monitoring, Wildfires extinguishing, Wildfires spreading, transmission lines tripping, and re-closing failure. In addition, the reason of the subsequent events in the evolution process are analysed by FTA, and the trapezoidal fuzzy theory is employed to calculate the probability of each events. Finally, based on the evaluation results, suggestions are provided for the evolution links with greater risks. Furthermore, transmission lines located in Xiangxi is introduced to present an application of the algorithm.
... Cruz et al. 2012). One reason this is so important in southern California is that power line fires are concentrated in the autumn months (Fig. 3) and are associated with extreme winds known locally as Santa Ana winds, which contribute to extreme fire behaviour (Mitchell 2013). Santa Ana winds present a major challenge for utilities in the region because high-velocity gusts may cause power lines to fall or arc, conductors to clash or trees to come into contact with the lines. ...
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The increasing extent of wildfires has prompted investigation into alternative fire management approaches to complement the traditional strategies of fire suppression and fuels manipulation. Wildfire prevention through ignition reduction is an approach with potential for success, but ignitions result from a variety of causes. If some ignition sources result in higher levels of area burned, then ignition prevention programmes could be optimised to target these distributions in space and time. We investigated the most common ignition causes in two southern California sub-regions, where humans are responsible for more than 95% of all fires, and asked whether these causes exhibited distinct spatial or intra-annual temporal patterns, or resulted in different extents of fire in 10–29-year periods, depending on sub-region. Different ignition causes had distinct spatial patterns and those that burned the most area tended to occur in autumn months. Both the number of fires and area burned varied according to cause of ignition, but the cause of the most numerous fires was not always the cause of the greatest area burned. In both sub-regions, power line ignitions were one of the top two causes of area burned: the other major causes were arson in one sub-region and power equipment in the other. Equipment use also caused the largest number of fires in both sub-regions. These results have important implications for understanding why, where and how ignitions are caused, and in turn, how to develop strategies to prioritise and focus fire prevention efforts. Fire extent has increased tremendously in southern California, and because most fires are caused by humans, ignition reduction offers a potentially powerful management strategy, especially if optimised to reflect the distinct spatial and temporal distributions in different ignition causes.
... Anthropogenic ignitions are usually accidental, for example, beginning with sparks created during metal work at construction sites, sparks from train wheels and mower blades hitting rocks, or escaped campfires and cigarette embers Keeley 2015, Short 2017). Overhead electric power systems are another frequent ignition source (Mitchell 2013, Keeley and Syphard 2018. Power line ignitions can occur when high winds cause energized wires to swing into one another, creating sparks (Sutlovic et al. 2019), windblown debris bridge wires and burst into flame (Ahmad et al. 2013), nest material bridge conductors and ignite (Burgio et al. 2014), and birds bridge conductors, are electrocuted, and fall to the ground on fire (Guil et al. 2017, Dwyer et al. 2019, Fenster et al. 2021). ...
Article
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Uncontrolled wildfires are occurring with increasing frequency across western North America due to a combination of wildfire suppression, climate change, impacts from mountain pine beetles (Dendroctonus ponderosae), alterations in range composition by nonnative grasses, and human population growth in fire‐prone landscapes. A poorly studied mechanism of wildland fire ignitions occurs when a bird perched on an overhead power line is electrocuted, its plumage ignites, and the burning bird falls into and ignites dry vegetation. Avian‐caused ignitions have been occasionally documented, but not spatially analyzed in the contiguous United States. We hypothesized that spatial analyses could demonstrate specific regions where ignitions from avian electrocutions occur most frequently. To test our hypothesis, we compared public reports of wildland fires ignited by bird electrocutions to Environmental Protection Agency ecoregions. We found reports of 44 wildland fires ignited by avian electrocutions in the contiguous U.S. from January 2014 to December 2018. The Mediterranean California ecoregion had the highest density of avian‐caused fires. It would be prudent for electric utilities in the Mediterranean California ecoregion in the U.S., and in fire‐prone landscapes globally, to develop fire mitigation plans that include modifying power poles to reduce risk of avian electrocutions and resulting wildfires. Wildland fires ignited by avian electrocutions are a risk multiplier for electric utilities, compounding semi‐predictable costs associated with wildlife take, power outages, and equipment damage with unpredictable costs associated with potentially catastrophic wildland fires. Electric utilities generally, particularly those in Mediterranean ecoregions, with cool, wet winters and hot, dry summers, should include in their fire mitigation plans, a focus on modifying power poles to reduce the risks of avian electrocutions and resulting wildfires.
... To expedite repairs and quick restoration of power offer it's necessary to grasp wherever the fault is found. Event of the digital techniques and microprocessor based systems helped in benefiting the progressive error spotting schemes for the few decades [4,5]. The Power transmission inspection involves three major farm duties: finding faults, categorization fault, and locating the faults. ...
Conference Paper
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This paper manages discovery of the problem areas in power transmission lines in an optimized thermal picture processing method. The technology followed in this research was automated hot spot detection base on image processing with hybrid algorithm. At every point of time video is changed over into number of picture by utilizing MATLAB coding. The hotspot is recognized from the picture outlines by utilizing the calculation. This calculation depends on finding the steepest development of progressive slopes of arranged estimations of info picture after certain picture pre-handling steps. A few post-preparing methods were connected for legitimate perception of distinguished districts in the subsequent pictures. The recognizable proof and the conceivable blame recognition from the Problem areas exhibit in the warm pictures are valued by time way and it can defend in a power transmission lines.
... At the same time, climate change is projected to have substantial impacts on infrastructure systems. For instance, coastal flooding and sea level rise are already damaging critical transportation, energy, and wastewater treatment infrastructure located along the coast (Azevedo de Almeida and Mostafavi, 2016), increased likelihood of extreme rainfall events has increased the risk of dam failures (Vahedifard et al., 2021), and drought-induced fires have led to preemptive power shutdowns in the United States (US) and Australia (Mitchell, 2013;Abatzoglou et al., 2020). Ensuring longterm viability of infrastructure thus requires climate adaptation, defined as "adjustment to actual Page 2 of 30 AUTHOR SUBMITTED MANUSCRIPT -ERIS-100119. ...
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Addressing climate change requires a shift in the planning, design, and operations of infrastructure. Reducing greenhouse gas emissions will require decarbonizing energy, water, transportation, and other infrastructures. And the long-term resilience of many infrastructure projects will be affected by expected changes in precipitation, sea level, heat and cold spells, and natural hazards like hurricanes and wildfires. Many scholars and practitioners have suggested that Environmental Impact Assessment (EIA) --a required review of the environmental impacts of infrastructure projects--can serve as an opportunity to encourage infrastructure to be more climate friendly. In the United States (like many other jurisdictions), federal agencies are not required to address climate change in EIA reviews, but guidance from the Council on Environmental Quality advises them to consider greenhouse gas emissions and the effects of climate change. This paper applied qualitative content analysis to assess integration of climate change into Environmental Impact Statements (EISs) in the United States. We found that most EISs included some consideration of climate change, most frequently with a few brief mentions rather than extensive integration. We also found more focus on climate mitigation than adaptation, in both recognizing potential impacts and managing those impacts. Surprisingly, infrastructure that is more directly related to climate change--water and energy infrastructure, as well as land management--had lower overall climate integration than transportation, information technology, or buildings and operations. As exploratory work, this research suggests that federal agencies could do more to mitigate greenhouse gas emissions in approved projects and in particular to make infrastructure more adaptive to climate change. The work also raises a number of questions as to whether EIA is the right regulatory tool to encourage climate friendly infrastructure.
... Forest fires caused by a variety of power line failures are rather uncommon in Europe, with the only exception of Switzerland [59,60], whereas they are frequent and important in other geographic areas such as California [60] and Australia [61]. Nevertheless, an extreme forest fire event caused by the contact between the vegetation and a 15 kV power line took place in Portugal in 2017 (the Pedrógão Grande fire, which burnt 28,624.7 ha, killed 66 people, and injured more than 250 people [62]). ...
Article
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Forest fires causes and motivations are poorly understood in southern and south-eastern Europe. This research aims to identify how experts perceive the different causes of forest fires as defined in the classification proposed by the European Commission in 2013. A panel of experts (N = 271) was gathered from the EU Southern Member States (France, Greece, Italy, Portugal, and Spain) and from Central (Switzerland) and south-eastern Europe (Croatia, Serbia, Bosnia and Herzegovina, Republic of North Macedonia, and Turkey). Experts were asked to answer a questionnaire to score the importance of the 29 fire causes using a five point (1–5) Likert Scale. Agricultural burnings received the highest score, followed by Deliberate fire for profit, and Vegetation management. Most of the events stem from Negligence, whereas malicious fire setting is arguably overestimated although there are differences among the countries. This research demonstrates the importance of different techniques to enhance the knowledge of the causes of the complex anthropogenic phenomenon of forest fire occurrence.
... It is important to notice that the presence of a fire WT day is not sufficient for the occurrence of extreme burned areas since fire ignition and suitable fuels and fuel condition also must be present. Previous studies have shown a relationship between the occurrence of strong winds (e.g., Santa Ana winds) and fire ignitions from utility lines (Mitchell, 2013). Future analysis should focus on the relationship between fire WTs and dry lightning. ...
Article
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Five of California's 10 largest wildfires occurred in 2020, with the largest complex exceeding the previous largest by more than 100%. The year follows a decade containing extraordinary fire activity. Previous trend investigations focused on changes in human activities and atmospheric thermodynamics, while the impacts of changing atmospheric dynamics are largely unknown. Here, we identify weather types (WTs) associated with historically large daily burned areas in eight Californian regions. These WTs characterize dominant fire weather regimes varying in fire behavior types (plume‐driven vs. wind‐driven fires) and seasonality. Most of the strongly large‐scale forced WTs such as Santa Ana and Diablo events increased in frequency during the 20th century particularly in the San Diego and Bay Area regions. These changes are likely not anthropogenically caused and the frequency of such events is projected to decrease under continuing climate change. However, significant future increases are found for WTs associated with thermal‐low‐pressure systems along the California coast and in the Sierra west region. These increases in southern California are mainly due to increasing greenhouse‐gas forcing and arise from the larger ocean‐land temperature gradient while aerosol forcing changes are driving most of the increased frequency in central and northern California due to a reduction of relative humidity over land and a strengthening of low‐pressure anomalies over the coast. These WT frequency changes could permit more weather favorable for large fire growth in summer and less in fall, further enhancing the risk of catastrophic fires due to hotter and drier summers in future climates.
... last access: 7 March 2021). One study of hospital admissions in Sydney, Australia, from 1994 to 2010 found that days with air pollution from extreme bushfires (as measured by PM 10 ) resulted in a 1.24 % admission increase for every 10 µg m −3 (Morgan et al., 2010). On the other hand, it should be noted that Australia is a country with a robust healthcare system, which significantly reduces vulnerability to the short-and long-term consequences of smoke and extreme heat. ...
Article
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Disastrous bushfires during the last months of 2019 and January 2020 affected Australia, raising the question to what extent the risk of these fires was exacerbated by anthropogenic climate change. To answer the question for southeastern Australia, where fires were particularly severe, affecting people and ecosystems, we use a physically based index of fire weather, the Fire Weather Index; long-term observations of heat and drought; and 11 large ensembles of state-of-the-art climate models. We find large trends in the Fire Weather Index in the fifth-generation European Centre for Medium-Range Weather Forecasts (ECMWF) Atmospheric Reanalysis (ERA5) since 1979 and a smaller but significant increase by at least 30 % in the models. Therefore, we find that climate change has induced a higher weather-induced risk of such an extreme fire season. This trend is mainly driven by the increase of temperature extremes. In agreement with previous analyses we find that heat extremes have become more likely by at least a factor of 2 due to the long-term warming trend. However, current climate models overestimate variability and tend to underestimate the long-term trend in these extremes, so the true change in the likelihood of extreme heat could be larger, suggesting that the attribution of the increased fire weather risk is a conservative estimate. We do not find an attributable trend in either extreme annual drought or the driest month of the fire season, September–February. The observations, however, show a weak drying trend in the annual mean. For the 2019/20 season more than half of the July–December drought was driven by record excursions of the Indian Ocean Dipole and Southern Annular Mode, factors which are included in the analysis here. The study reveals the complexity of the 2019/20 bushfire event, with some but not all drivers showing an imprint of anthropogenic climate change. Finally, the study concludes with a qualitative review of various vulnerability and exposure factors that each play a role, along with the hazard in increasing or decreasing the overall impact of the bushfires.
... Most prior work focuses on environment-caused wildfires [4], [5] or humancaused wildfires [6], and few focus on those cause by powergrids. Previous studies using statistical methods only investigated correlation between a small number of environmental features (i.e., wind speed, fuel moisture) and the ignitions triggered by power lines [7]. Weather and vegetation data were commonly used in past work [8], [9], but grid infrastructure data has been minimally investigated. ...
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This paper examines the use of risk models to predict the timing and location of wildfires caused by electricity infrastructure. Our data include historical ignition and wire-down points triggered by grid infrastructure collected between 2015 to 2019 in Pacific Gas & Electricity territory along with various weather, vegetation, and very high resolution data on grid infrastructure including location, age, materials. With these data we explore a range of machine learning methods and strategies to manage training data imbalance. The best area under the receiver operating characteristic we obtain is 0.776 for distribution feeder ignitions and 0.824 for transmission line wire-down events, both using the histogram-based gradient boosting tree algorithm (HGB) with under-sampling. We then use these models to identify which information provides the most predictive value. After line length, we find that weather and vegetation features dominate the list of top important features for ignition or wire-down risk. Distribution ignition models show more dependence on slow-varying vegetation variables such as burn index, energy release content, and tree height, whereas transmission wire-down models rely more on primary weather variables such as wind speed and precipitation. These results point to the importance of improved vegetation modeling for feeder ignition risk models, and improved weather forecasting for transmission wire-down models. We observe that infrastructure features make small but meaningful improvements to risk model predictive power.
... The researcher strongly recommends that the present survey [39][40][41][42][43][44][45][46][47][48][49] to the present and future researchers, the thermal image inspection of power lines. This inspecting facility are indented in the inspection methods to find a possible electrical difficulty and it is utilizing with different parameters or different natural calamities. ...
Conference Paper
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There are many issues in power system transmission lines maintenance one such issue is the identification o f exact hotspots. These hotspots lead to the deterioration of the power system components. If this deterioration is not addressed then cracks on insulators, spacers dampers braking will arise, which may lead to the damages in the transmission system. This damage may lead to power shutdown in the power grid or causality of humans being and animals. The current scenario of transmission system maintenance demands an urgent requirement in the identification of hotspots on the transmission system so that the impact of the damage may be reduced. In the identification of the deterioration in power transmission system, there are several types of inspection methods are available. This paper gives the bibliography survey on research and development in the field of hotspot identification and deterioration caused by it in the transmission lines. This paper analysis 51 published papers in area of hotspot & Impact of deterioration, published in the past 25 years.
... People use riverbanks for recreational activities, and this raises the risk of fire from campfires and careless cigarette smoking. The distance to roads, settlements, agricultural areas, and rivers and the population density have been listed as risky environmental factors in many studies (Eskandari, 2017;Gheshlaghi et al., 2020;Hoang et al., 2020;Mitchell, 2013;Saklani, 2008;Sari, 2021;Suryabhagavan et al., 2016). Environmental criteria maps are shown in Fig. 5. ...
Article
This study proposed an integrated approach to generating a forest fire risk map. It used geographic information system–based multiple criteria decision analysis (GIS-MCDA) with the analytic hierarchy process (AHP) and a statistical index (SI). The research was carried out at the Mersin Regional Directorate of Forestry (RDF) in the eastern Mediterranean region of Turkey. Four main criteria, the forest structure, topography, environment, and climate, and 16 subcriteria were used to create the fire risk map. The weight of each criterion was determined using the AHP. The AHP model revealed that environmental factors are the most influential in igniting forest fires, followed by the forest structure. In order to evaluate the results, 990 historical forest fire ignition points were obtained from the Mersin RDF. According to the forest fire risk map, more than 85% of the ignition points were in areas classified as having an extreme or high risk for forest fires. The findings show that the study area is highly prone to forest fires. The relative operating characteristic curve and area under the curve were used to validate the accuracy of the fire risk map. This validation revealed a very high accuracy of 0.775 for the AHP model, indicating a high accuracy in forest fire risk mapping, and the map produced was consistent and reliable. The AHP model and its results will assist decision makers in taking necessary precautions to prevent forest fires and to minimize fire damage, particularly in the eastern Mediterranean region.
... While multiple variables and indicators are used to make the decision to conduct a PSPS event, utilities typically consider strong winds, high temperatures, low humidity, and current drought conditions in their decision-making. Wind in particular can cause elastic extension failures (e.g., electric lines touching objects) or fatigue failure (e.g., electrical grid components or surrounding objects falling) (6). A comprehensive study by (7) using PG&E data found that rural areas, distribution lines (as opposed to transmission lines or substations), and vegetation contact (as opposed to buildings) had high proportions of wildfire ignition events. ...
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... The effects are diverse depending on many factors, like weather conditions, vegetation affected, land cover, land management before and after the incident, the geographical region affected, or human vegetation management and risk mitigation. Wildfires occur by a combination of conditions created either by human intervention (e.g., power lines failures [5]) or by unpredictable events (such as lightnings [6,7], and thus are much harder to anticipate). As natural environments become more vulnerable to this kind of events, cities and inhabitable places need to be made more resilient, as they are likely to become more frequent due to changes in climate [3]. ...
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... This is because it is an important indicator of the "preconditioning" that is discussed in the literature (Urbieta et al., 2015;Trigo et al., 2016;Littell et al., 2009;Gedalof et al., 2005;Crimmins and Comrie, 2005). 2. Wind gust: Wind gust is another important feature known to affect acres burned during a wildfire event, mostly attributed to its direct effect on the rate of wildfire spread (Fovell and Gallagher, 2018;Mitchell, 2013). Its importance is apparent since three variables representing wind gust is among the top 10 variables (see Figure 9). ...
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... The researcher strongly recommends that the present survey [39][40][41][42][43][44][45][46][47][48][49] to the present and future researchers, the thermal image inspection of power lines. This inspecting facility are indented in the inspection methods to find a possible electrical difficulty and it is utilizing with different parameters or different natural calamities. ...
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