To accurately simulate realistic pedestrian evacuation from a fire, a cellular automaton model of the dynamic changes in pedestrian movement parameters is developed in conjunction with fire dynamics software. The fire dynamics software is used to simulate the spread of smoke within the scene to obtain visibility and CO concentration data within the scene. We imported the smoke data into the cellular automata and adjusted the pedestrian movement speed over time, resulting in simulation data that closely align with reality. The results show that for the single-room scenario, as pedestrian density increased from 0.1 to 0.5 persons per square meter (p/m2), the influence of the percentage of pedestrians familiar with their location on evacuation efficiency decreased from 44.93% to 24.52%. Conversely, in the multi-room scenario, it increased from 23.68% to 38.79%. The proportion of pedestrians less affected by smoke decreases and stabilizes as the CO yield increases. In the single-room scenario, when the CO yield is below 10%, the crowd with a low percentage of pedestrians familiar with the site is more affected by smoke than those with a high percentage. In the multi-room scenario, the victimization rate of the crowd follows an increasing-then-decreasing curve, ultimately stabilizing with changes in CO yield.
{"title":"Cellular Automaton Model for Pedestrian Evacuation Considering Impacts of Fire Products","authors":"Yuechan Liu, Junyan Li, Chao Sun","doi":"10.3390/fire6080320","DOIUrl":"https://doi.org/10.3390/fire6080320","url":null,"abstract":"To accurately simulate realistic pedestrian evacuation from a fire, a cellular automaton model of the dynamic changes in pedestrian movement parameters is developed in conjunction with fire dynamics software. The fire dynamics software is used to simulate the spread of smoke within the scene to obtain visibility and CO concentration data within the scene. We imported the smoke data into the cellular automata and adjusted the pedestrian movement speed over time, resulting in simulation data that closely align with reality. The results show that for the single-room scenario, as pedestrian density increased from 0.1 to 0.5 persons per square meter (p/m2), the influence of the percentage of pedestrians familiar with their location on evacuation efficiency decreased from 44.93% to 24.52%. Conversely, in the multi-room scenario, it increased from 23.68% to 38.79%. The proportion of pedestrians less affected by smoke decreases and stabilizes as the CO yield increases. In the single-room scenario, when the CO yield is below 10%, the crowd with a low percentage of pedestrians familiar with the site is more affected by smoke than those with a high percentage. In the multi-room scenario, the victimization rate of the crowd follows an increasing-then-decreasing curve, ultimately stabilizing with changes in CO yield.","PeriodicalId":36395,"journal":{"name":"Fire-Switzerland","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2023-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42124433","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
S. Misyura, V. Morozov, I. Donskoy, N. Shlegel, V. Dorokhov
The process of combustion of a liquid fuel layer (diesel, kerosene, gasoline, separated petroleum, and oil) in the presence of CO2 hydrate has been studied. These fuels are widely used in engineering, which explains the great interest in effective methods of extinguishing. Extinguishing liquid fuels is quite a complicated scientific and technical task. It is often necessary to deal with fire extinction during oil spills and at fuel burning in large containers outdoors and in warehouses. Recently, attention to new extinguishing methods has increased. Advances in technology of the production, storage, and transportation of inert gas hydrates enhance the opportunities of using CO2 hydrate for extinguishing liquid fuels. Previous studies have shown a fairly high efficiency of CO2 hydrate (compared to water spray) in the extinction of volumetric fires. To date, there are neither experimental data nor methods for determining the dissociation rate of CO2 hydrate powder at the time of the gas hydrate fall on the burning layer of liquid fuel. The value of the dissociation rate is important to know in order to determine the temperatures of stable combustion and, accordingly, the mass of CO2 hydrate required to extinguish the flame. For the first time, a method jointly accounting for both the combustion of liquid fuel and the dissociation rate of the falling powder of gas hydrate at a negative temperature is proposed. The combustion stability depends on many factors. This paper defines three characteristic modes of evaporation of a liquid fuel layer, depending on the prevalence of vapor diffusion or free gas convection. The influence of the diameter and height of the layer on the nature of fuel evaporation is investigated.
{"title":"Combustion of Liquid Fuels in the Presence of CO2 Hydrate Powder","authors":"S. Misyura, V. Morozov, I. Donskoy, N. Shlegel, V. Dorokhov","doi":"10.3390/fire6080318","DOIUrl":"https://doi.org/10.3390/fire6080318","url":null,"abstract":"The process of combustion of a liquid fuel layer (diesel, kerosene, gasoline, separated petroleum, and oil) in the presence of CO2 hydrate has been studied. These fuels are widely used in engineering, which explains the great interest in effective methods of extinguishing. Extinguishing liquid fuels is quite a complicated scientific and technical task. It is often necessary to deal with fire extinction during oil spills and at fuel burning in large containers outdoors and in warehouses. Recently, attention to new extinguishing methods has increased. Advances in technology of the production, storage, and transportation of inert gas hydrates enhance the opportunities of using CO2 hydrate for extinguishing liquid fuels. Previous studies have shown a fairly high efficiency of CO2 hydrate (compared to water spray) in the extinction of volumetric fires. To date, there are neither experimental data nor methods for determining the dissociation rate of CO2 hydrate powder at the time of the gas hydrate fall on the burning layer of liquid fuel. The value of the dissociation rate is important to know in order to determine the temperatures of stable combustion and, accordingly, the mass of CO2 hydrate required to extinguish the flame. For the first time, a method jointly accounting for both the combustion of liquid fuel and the dissociation rate of the falling powder of gas hydrate at a negative temperature is proposed. The combustion stability depends on many factors. This paper defines three characteristic modes of evaporation of a liquid fuel layer, depending on the prevalence of vapor diffusion or free gas convection. The influence of the diameter and height of the layer on the nature of fuel evaporation is investigated.","PeriodicalId":36395,"journal":{"name":"Fire-Switzerland","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2023-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49508564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Morales-Máximo, L. López-Sosa, J. Alvarado-Flores, Jorge Víctor Alcaraz-Vera, Carlos A. García, Margarito Álvarez-Jara, J. G. Rutiaga-Quiñones
The generation of biomass residues in different productive activities of rural communities in Mexico represents an area of opportunity for the generation of bioenergy for various purposes. Solid biofuels (SBF), for example, are an alternative for the exploitation of these residues. The present study shows a comprehensive proposal for the analysis of residues of Pinus spp. generated by the artisanal sector of a rural community in Mexico. The proposal is based on four stages: a) characterization of the physico-chemical and functional properties of the residues, by Scanning Electron Microscopy (SEM), Infrared (FTIR) and Raman Spectroscopy, Thermogravimetry (TGA-DTG), determining the calorific coefficient and polymeric compounds present by fiber analysis; (b) spatial, temporal and dimensional analysis of the waste generated in the town studied; (c) assessment of the energy potential available in space and time; (d) definition of guidelines for the management of solid biofuels for the community through collection, processing and final disposal centers. The results of the assessment of timber residue from 50 artisan workshops that represent 25% of the total in the community show that the identified heating value of the dry residue ranges from 17.6 MJ/kg to 18.1 MJ/kg, attributed to the presence of polymeric compounds such as cellulose, hemicellulose and lignin, the latter in the order of 28%, which contributes to a high energy potential, and whose compounds were identified by TGA-DTG analysis, FTIR, SEM and fiber analysis. The energy potential was estimated at approximately 7 TJ/year for the analyzed workshops. In which case, the economic savings obtained from unburned firewood would amount to about $20,000 USD/year. As regards the reduction in firewood consumption due to the use of residues for energy purposes, about 350 Tn/year would be mitigated, which would reduce the community’s emissions by more than 76 TnCO2/year. A strategic management proposal was also established, aimed at providing spaces for the collection, processing and final disposal of solid biofuels from wood residues, which in sum represent an energy alternative that is sustainable in environmental, economic and social terms, for the same community.
{"title":"Multifactorial Assessment of the Bioenergetic Potential of Residual Biomass of Pinus spp. in a Rural Community: From Functional Characterization to Mapping of the Available Energy Resource","authors":"M. Morales-Máximo, L. López-Sosa, J. Alvarado-Flores, Jorge Víctor Alcaraz-Vera, Carlos A. García, Margarito Álvarez-Jara, J. G. Rutiaga-Quiñones","doi":"10.3390/fire6080317","DOIUrl":"https://doi.org/10.3390/fire6080317","url":null,"abstract":"The generation of biomass residues in different productive activities of rural communities in Mexico represents an area of opportunity for the generation of bioenergy for various purposes. Solid biofuels (SBF), for example, are an alternative for the exploitation of these residues. The present study shows a comprehensive proposal for the analysis of residues of Pinus spp. generated by the artisanal sector of a rural community in Mexico. The proposal is based on four stages: a) characterization of the physico-chemical and functional properties of the residues, by Scanning Electron Microscopy (SEM), Infrared (FTIR) and Raman Spectroscopy, Thermogravimetry (TGA-DTG), determining the calorific coefficient and polymeric compounds present by fiber analysis; (b) spatial, temporal and dimensional analysis of the waste generated in the town studied; (c) assessment of the energy potential available in space and time; (d) definition of guidelines for the management of solid biofuels for the community through collection, processing and final disposal centers. The results of the assessment of timber residue from 50 artisan workshops that represent 25% of the total in the community show that the identified heating value of the dry residue ranges from 17.6 MJ/kg to 18.1 MJ/kg, attributed to the presence of polymeric compounds such as cellulose, hemicellulose and lignin, the latter in the order of 28%, which contributes to a high energy potential, and whose compounds were identified by TGA-DTG analysis, FTIR, SEM and fiber analysis. The energy potential was estimated at approximately 7 TJ/year for the analyzed workshops. In which case, the economic savings obtained from unburned firewood would amount to about $20,000 USD/year. As regards the reduction in firewood consumption due to the use of residues for energy purposes, about 350 Tn/year would be mitigated, which would reduce the community’s emissions by more than 76 TnCO2/year. A strategic management proposal was also established, aimed at providing spaces for the collection, processing and final disposal of solid biofuels from wood residues, which in sum represent an energy alternative that is sustainable in environmental, economic and social terms, for the same community.","PeriodicalId":36395,"journal":{"name":"Fire-Switzerland","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2023-08-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47046671","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chengtuo Jin, Tao Wang, Naji Alhusaini, Shenghui Zhao, Huilin Liu, Kun Xu, Jin Zhang
Among various calamities, conflagrations stand out as one of the most-prevalent and -menacing adversities, posing significant perils to public safety and societal progress. Traditional fire-detection systems primarily rely on sensor-based detection techniques, which have inherent limitations in accurately and promptly detecting fires, especially in complex environments. In recent years, with the advancement of computer vision technology, video-oriented fire detection techniques, owing to their non-contact sensing, adaptability to diverse environments, and comprehensive information acquisition, have progressively emerged as a novel solution. However, approaches based on handcrafted feature extraction struggle to cope with variations in smoke or flame caused by different combustibles, lighting conditions, and other factors. As a powerful and flexible machine learning framework, deep learning has demonstrated significant advantages in video fire detection. This paper summarizes deep-learning-based video-fire-detection methods, focusing on recent advances in deep learning approaches and commonly used datasets for fire recognition, fire object detection, and fire segmentation. Furthermore, this paper provides a review and outlook on the development prospects of this field.
{"title":"Video Fire Detection Methods Based on Deep Learning: Datasets, Methods, and Future Directions","authors":"Chengtuo Jin, Tao Wang, Naji Alhusaini, Shenghui Zhao, Huilin Liu, Kun Xu, Jin Zhang","doi":"10.3390/fire6080315","DOIUrl":"https://doi.org/10.3390/fire6080315","url":null,"abstract":"Among various calamities, conflagrations stand out as one of the most-prevalent and -menacing adversities, posing significant perils to public safety and societal progress. Traditional fire-detection systems primarily rely on sensor-based detection techniques, which have inherent limitations in accurately and promptly detecting fires, especially in complex environments. In recent years, with the advancement of computer vision technology, video-oriented fire detection techniques, owing to their non-contact sensing, adaptability to diverse environments, and comprehensive information acquisition, have progressively emerged as a novel solution. However, approaches based on handcrafted feature extraction struggle to cope with variations in smoke or flame caused by different combustibles, lighting conditions, and other factors. As a powerful and flexible machine learning framework, deep learning has demonstrated significant advantages in video fire detection. This paper summarizes deep-learning-based video-fire-detection methods, focusing on recent advances in deep learning approaches and commonly used datasets for fire recognition, fire object detection, and fire segmentation. Furthermore, this paper provides a review and outlook on the development prospects of this field.","PeriodicalId":36395,"journal":{"name":"Fire-Switzerland","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2023-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42302016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xiuyan Gao, Fan Yang, Chuan-Xin Zhang, Qixiang Chen, Yuan Yuan
The soot produced by fossil fuel combustion affects climate and human health, and the ethylene laminar flame is a crucial research object of soot generation. After verifying the accuracy of the numerical calculation model by comparing experimental data, the impact of changes in inlet flow rate and fuel flow composition operating conditions on the generation of soot were compared and analyzed. The calculated results obtained are consistent with the experimental data in terms of distribution trend. The deviation of the calculated peak integral smoke volume fraction is only 5%. Under the operating conditions set in this study, increasing the volume flow rate of the accompanying air will increase the volume fraction of soot generated by the ethylene laminar diffusion flame. Increasing the fuel volume flow rate will first increase and then decrease the volume fraction of soot.
{"title":"Numerical Simulation of Soot Formation in Ethylene Laminar Diffusion Flame","authors":"Xiuyan Gao, Fan Yang, Chuan-Xin Zhang, Qixiang Chen, Yuan Yuan","doi":"10.3390/fire6080316","DOIUrl":"https://doi.org/10.3390/fire6080316","url":null,"abstract":"The soot produced by fossil fuel combustion affects climate and human health, and the ethylene laminar flame is a crucial research object of soot generation. After verifying the accuracy of the numerical calculation model by comparing experimental data, the impact of changes in inlet flow rate and fuel flow composition operating conditions on the generation of soot were compared and analyzed. The calculated results obtained are consistent with the experimental data in terms of distribution trend. The deviation of the calculated peak integral smoke volume fraction is only 5%. Under the operating conditions set in this study, increasing the volume flow rate of the accompanying air will increase the volume fraction of soot generated by the ethylene laminar diffusion flame. Increasing the fuel volume flow rate will first increase and then decrease the volume fraction of soot.","PeriodicalId":36395,"journal":{"name":"Fire-Switzerland","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2023-08-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46066061","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Assessing the characteristics of fuel flammability during fire is of major significance regarding fire intensity and fire spread control. Under the background of shifting forest composition from heliophytic to mesophytic species in mixed-oak forests, our objective is to determine the impacts of species-driven changes in fuel flammability characteristics and the specific relationships between fuel ignition variations at the species level. Oak and maple fuels were collected from ninety-four plots established in Zaleski State Forest, Ohio. A total of 30 combustion samples were separated (15 oak samples and 15 maple samples), with each combustion sample weighing 20 g to ignite under a laboratory fume hood. Our results determined that oak fuel showed significantly higher flame temperatures than maple fuel, and the fuel consumption and combustion duration time both varied between oak and maple fuel. These findings indicated that the shift from oak forest to mesophytic species could change a fire’s behavior. Combined with the cooler, moister, and less-flammable forest conditions generated by these mesophytic species, fires may not be able to reach their historical fire intensities, suggesting that updated data and new insights are needed for fire management.
{"title":"Effects of Wildland Fuel Composition on Fire Intensity","authors":"Ziyu Dong, Roger A. Williams","doi":"10.3390/fire6080312","DOIUrl":"https://doi.org/10.3390/fire6080312","url":null,"abstract":"Assessing the characteristics of fuel flammability during fire is of major significance regarding fire intensity and fire spread control. Under the background of shifting forest composition from heliophytic to mesophytic species in mixed-oak forests, our objective is to determine the impacts of species-driven changes in fuel flammability characteristics and the specific relationships between fuel ignition variations at the species level. Oak and maple fuels were collected from ninety-four plots established in Zaleski State Forest, Ohio. A total of 30 combustion samples were separated (15 oak samples and 15 maple samples), with each combustion sample weighing 20 g to ignite under a laboratory fume hood. Our results determined that oak fuel showed significantly higher flame temperatures than maple fuel, and the fuel consumption and combustion duration time both varied between oak and maple fuel. These findings indicated that the shift from oak forest to mesophytic species could change a fire’s behavior. Combined with the cooler, moister, and less-flammable forest conditions generated by these mesophytic species, fires may not be able to reach their historical fire intensities, suggesting that updated data and new insights are needed for fire management.","PeriodicalId":36395,"journal":{"name":"Fire-Switzerland","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2023-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44753582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Xingang Xie, Ke Chen, Yiran Guo, Botao Tan, Lumeng Chen, Min Huang
Flame recognition is an important technique in firefighting, but existing image flame-detection methods are slow, low in accuracy, and cannot accurately identify small flame areas. Current detection technology struggles to satisfy the real-time detection requirements of firefighting drones at fire scenes. To improve this situation, we developed a YOLOv5-based real-time flame-detection algorithm. This algorithm can detect flames quickly and accurately. The main improvements are: (1) The embedded coordinate attention mechanism helps the model more precisely find and detect the target of interest. (2) We advanced the detection layer for small targets to enhance the model’s associated identification ability. (3) We introduced a novel loss function, α-IoU, and improved the accuracy of the regression results. (4) We combined the model with transfer learning to improve its accuracy. The experimental results indicate that the enhanced YOLOv5′s mAP can reach 96.6%, 5.4% higher than the original. The model needed 0.0177 s to identify a single image, demonstrating its efficiency. In summary, the enhanced YOLOv5 network model’s overall efficiency is superior to that of the original algorithm and existing mainstream identification approaches.
{"title":"A Flame-Detection Algorithm Using the Improved YOLOv5","authors":"Xingang Xie, Ke Chen, Yiran Guo, Botao Tan, Lumeng Chen, Min Huang","doi":"10.3390/fire6080313","DOIUrl":"https://doi.org/10.3390/fire6080313","url":null,"abstract":"Flame recognition is an important technique in firefighting, but existing image flame-detection methods are slow, low in accuracy, and cannot accurately identify small flame areas. Current detection technology struggles to satisfy the real-time detection requirements of firefighting drones at fire scenes. To improve this situation, we developed a YOLOv5-based real-time flame-detection algorithm. This algorithm can detect flames quickly and accurately. The main improvements are: (1) The embedded coordinate attention mechanism helps the model more precisely find and detect the target of interest. (2) We advanced the detection layer for small targets to enhance the model’s associated identification ability. (3) We introduced a novel loss function, α-IoU, and improved the accuracy of the regression results. (4) We combined the model with transfer learning to improve its accuracy. The experimental results indicate that the enhanced YOLOv5′s mAP can reach 96.6%, 5.4% higher than the original. The model needed 0.0177 s to identify a single image, demonstrating its efficiency. In summary, the enhanced YOLOv5 network model’s overall efficiency is superior to that of the original algorithm and existing mainstream identification approaches.","PeriodicalId":36395,"journal":{"name":"Fire-Switzerland","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2023-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48257410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hamid Boubekraoui, Yazid Maouni, Abdelilah Ghallab, M. Draoui, A. Maouni
In recent years, changes in climate, land cover, and sociodemographic dynamics have created new challenges in wildfire management. As a result, advanced and integrated approaches in wildfire science have emerged. The objective of our study is to use geospatial analysis to identify strategic responses to wildfires in the Tangier-Tetouan-Al Hoceima (TTA) region, widely reputed to exhibit the most significant incidences of wildfires in Morocco. We adopted a combined approach, using burned area products (Fire_CCI51: 2002–2020) from the Moderate Resolution Imaging Spectroradiometer (MODIS) and active fires from the Fire Information for Resource Management System (FIRMS: 2001–2022) and processing them with spatiotemporal statistical methods: optimized hotspot analysis (OHA) and emerging hotspot analysis (EHA). The main findings indicate that the TTA region recorded an average of 39.78 km2/year of burned areas, mostly located in forests (74%), mainly cork oak and matorral stands (50%). The OHA detected hotspots covering 2081 km2, with 63% concentrated in the provinces of Chefchaouen and Larache. Meanwhile, clusters of EHA extended over 740 km2 and were composed of the oscillating coldspot (OCS) and oscillating hotspot (OHS) patterns at 50% and 30%, respectively. Additionally, an average of 149 fires/year occurred, located mostly in forests (75%), mainly cork oak and matorral stands (61%). The OHA detected active fire hotspots covering 3904 km2, with 60% located in the provinces of Chefchaouen and Larache. Clusters of EHA over 941 km2 were composed of the oscillating hotspot (OHS) and new hotspot (NHS) patterns at 57% and 25%, respectively. The prevalence of the oscillating and new models mirrors, respectively, the substantial fluctuations in wildfires within the region alternating between periods of high and low wildfire activities and the marked increase in fires in recent times, which has occasioned the emergence of novel hotspots. Additionally, we identified six homogeneous wildfire zones to which we assigned three strategic responses: “maintain” (73% of the territory), “monitor and raise awareness” (14% of the territory), and “reinforce” (13% of the territory). These strategies address current wildfire management measures, which include prevention, risk analysis, preparation, intervention, and rehabilitation. To better allocate firefighting resources, strategic responses were classified into four priorities (very high, high, medium, and low). Last, the wildfire zoning and strategic responses were validated using burned areas from 2021 to 2023, and a global scheme was suggested to assess the effectiveness of future wildfire measures.
{"title":"Wildfires Risk Assessment Using Hotspot Analysis and Results Application to Wildfires Strategic Response in the Region of Tangier-Tetouan-Al Hoceima, Morocco","authors":"Hamid Boubekraoui, Yazid Maouni, Abdelilah Ghallab, M. Draoui, A. Maouni","doi":"10.3390/fire6080314","DOIUrl":"https://doi.org/10.3390/fire6080314","url":null,"abstract":"In recent years, changes in climate, land cover, and sociodemographic dynamics have created new challenges in wildfire management. As a result, advanced and integrated approaches in wildfire science have emerged. The objective of our study is to use geospatial analysis to identify strategic responses to wildfires in the Tangier-Tetouan-Al Hoceima (TTA) region, widely reputed to exhibit the most significant incidences of wildfires in Morocco. We adopted a combined approach, using burned area products (Fire_CCI51: 2002–2020) from the Moderate Resolution Imaging Spectroradiometer (MODIS) and active fires from the Fire Information for Resource Management System (FIRMS: 2001–2022) and processing them with spatiotemporal statistical methods: optimized hotspot analysis (OHA) and emerging hotspot analysis (EHA). The main findings indicate that the TTA region recorded an average of 39.78 km2/year of burned areas, mostly located in forests (74%), mainly cork oak and matorral stands (50%). The OHA detected hotspots covering 2081 km2, with 63% concentrated in the provinces of Chefchaouen and Larache. Meanwhile, clusters of EHA extended over 740 km2 and were composed of the oscillating coldspot (OCS) and oscillating hotspot (OHS) patterns at 50% and 30%, respectively. Additionally, an average of 149 fires/year occurred, located mostly in forests (75%), mainly cork oak and matorral stands (61%). The OHA detected active fire hotspots covering 3904 km2, with 60% located in the provinces of Chefchaouen and Larache. Clusters of EHA over 941 km2 were composed of the oscillating hotspot (OHS) and new hotspot (NHS) patterns at 57% and 25%, respectively. The prevalence of the oscillating and new models mirrors, respectively, the substantial fluctuations in wildfires within the region alternating between periods of high and low wildfire activities and the marked increase in fires in recent times, which has occasioned the emergence of novel hotspots. Additionally, we identified six homogeneous wildfire zones to which we assigned three strategic responses: “maintain” (73% of the territory), “monitor and raise awareness” (14% of the territory), and “reinforce” (13% of the territory). These strategies address current wildfire management measures, which include prevention, risk analysis, preparation, intervention, and rehabilitation. To better allocate firefighting resources, strategic responses were classified into four priorities (very high, high, medium, and low). Last, the wildfire zoning and strategic responses were validated using burned areas from 2021 to 2023, and a global scheme was suggested to assess the effectiveness of future wildfire measures.","PeriodicalId":36395,"journal":{"name":"Fire-Switzerland","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2023-08-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42443743","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. de Sales, Zackary Werner, João Gilberto de Souza Ribeiro
This study uses a combined research approach based on remote-sensing and numerical modeling to quantify the effects of burned areas on the surface climate in the two Brazilian biomes most affected by fires: the tropical savanna and the Amazon rainforest. Our estimates indicate that between 2007 and 2020, approximately 6% of the savanna and 2% of the rainforest were burned on average. Non-parametric regressions based on 14-year climate model simulations indicate that latent heat flux decreases on average by approximately 0.17 W m−2 in the savanna and 0.60 W m−2 in the rainforest per each 1 km2 burned, with most of the impacts registered during the onset of the wet season. Sensible and ground heat fluxes are also impacted but at less intensity. Surface air is also warmer and drier, especially over rainforest burned sites. On average, fire reduced gross primary production in the savanna and rainforest by 12% and 10%, respectively, in our experiments.
本研究采用基于遥感和数值模拟的综合研究方法，量化了受火灾影响最严重的两个巴西生物群落:热带稀树草原和亚马逊雨林的燃烧面积对地表气候的影响。我们的估计表明，在2007年至2020年间，平均约有6%的热带草原和2%的雨林被烧毁。基于14年气候模式模拟的非参数回归表明，每燃烧1 km2，热带草原的潜热通量平均减少约0.17 W m−2，雨林的潜热通量平均减少0.60 W m−2，其中大部分影响记录在雨季开始期间。感热通量和地热通量也受到影响，但强度较小。地表空气也变得更加温暖和干燥，尤其是在雨林被烧毁的地方。在我们的实验中，火灾平均使热带稀树草原和雨林的总初级生产分别减少了12%和10%。
{"title":"Quantifying Fire-Induced Surface Climate Changes in the Savanna and Rainforest Biomes of Brazil","authors":"F. de Sales, Zackary Werner, João Gilberto de Souza Ribeiro","doi":"10.3390/fire6080311","DOIUrl":"https://doi.org/10.3390/fire6080311","url":null,"abstract":"This study uses a combined research approach based on remote-sensing and numerical modeling to quantify the effects of burned areas on the surface climate in the two Brazilian biomes most affected by fires: the tropical savanna and the Amazon rainforest. Our estimates indicate that between 2007 and 2020, approximately 6% of the savanna and 2% of the rainforest were burned on average. Non-parametric regressions based on 14-year climate model simulations indicate that latent heat flux decreases on average by approximately 0.17 W m−2 in the savanna and 0.60 W m−2 in the rainforest per each 1 km2 burned, with most of the impacts registered during the onset of the wet season. Sensible and ground heat fluxes are also impacted but at less intensity. Surface air is also warmer and drier, especially over rainforest burned sites. On average, fire reduced gross primary production in the savanna and rainforest by 12% and 10%, respectively, in our experiments.","PeriodicalId":36395,"journal":{"name":"Fire-Switzerland","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2023-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47492342","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Roman Berčák, J. Holuša, J. Kaczmarowski, Łukasz Tyburski, R. Szczygieł, Alexander C. Held, H. Vacik, J. Slivinský, Ivan Chromek
Forest fires are becoming a more significant problem in Central Europe, but their danger is not as high as that in Southern Europe. The exception, however, is forest fires occurring in disturbed areas (windthrow and bark beetle outbreak areas), which are comparable in severity and danger to the most serious forest fires. In this study, we describe the current situation in Central European countries in terms of fire protection for disturbed areas in managed forests and forest stands left to spontaneously develop (secondary succession). If a country has regulations and strategies in this area, they are often only published in the local language. In this review, we combine information from all Central European countries and summarize it in a unified international language, provide an opportunity for local authorities to express their own experiences, and integrate data from worldwide scientific research. Thus, this paper may be considered a universal guide for managing fire protection and preparedness in disturbed areas and can serve as a reference for the establishment of strict legislative rules at the state level. These laws must be obligatory for all stakeholders in individual countries. The motivation for this study was two large forest fires in an area left to spontaneously develop in the Bohemian Switzerland National Park in the Czech Republic and Harz Mountains in Germany in the summer of 2022. These incidents revealed that fire prevention legislation was inadequate or nonexistent in these areas. The strategy of the European Union is to increase the size of protected areas and spontaneous development areas. Therefore, we consider it necessary to provide governments with relevant information on this topic to create conditions for better management of these destructive events.
{"title":"Fire Protection Principles and Recommendations in Disturbed Forest Areas in Central Europe: A Review","authors":"Roman Berčák, J. Holuša, J. Kaczmarowski, Łukasz Tyburski, R. Szczygieł, Alexander C. Held, H. Vacik, J. Slivinský, Ivan Chromek","doi":"10.3390/fire6080310","DOIUrl":"https://doi.org/10.3390/fire6080310","url":null,"abstract":"Forest fires are becoming a more significant problem in Central Europe, but their danger is not as high as that in Southern Europe. The exception, however, is forest fires occurring in disturbed areas (windthrow and bark beetle outbreak areas), which are comparable in severity and danger to the most serious forest fires. In this study, we describe the current situation in Central European countries in terms of fire protection for disturbed areas in managed forests and forest stands left to spontaneously develop (secondary succession). If a country has regulations and strategies in this area, they are often only published in the local language. In this review, we combine information from all Central European countries and summarize it in a unified international language, provide an opportunity for local authorities to express their own experiences, and integrate data from worldwide scientific research. Thus, this paper may be considered a universal guide for managing fire protection and preparedness in disturbed areas and can serve as a reference for the establishment of strict legislative rules at the state level. These laws must be obligatory for all stakeholders in individual countries. The motivation for this study was two large forest fires in an area left to spontaneously develop in the Bohemian Switzerland National Park in the Czech Republic and Harz Mountains in Germany in the summer of 2022. These incidents revealed that fire prevention legislation was inadequate or nonexistent in these areas. The strategy of the European Union is to increase the size of protected areas and spontaneous development areas. Therefore, we consider it necessary to provide governments with relevant information on this topic to create conditions for better management of these destructive events.","PeriodicalId":36395,"journal":{"name":"Fire-Switzerland","volume":" ","pages":""},"PeriodicalIF":3.2,"publicationDate":"2023-08-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41392936","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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