Years after wildfires burn forests and watersheds(分水岭)in the Western US,pollutants left behind continue to poison rivers and streams,and have existed for a longer time than scientists previously estimated.
A series of 14 destructive wildfires swept across the US West Coast,particularly Southern California,from January 7 to 31,2025.The fires were exacerbated by drought conditions,low humidity,accumulated vegetation from ...A series of 14 destructive wildfires swept across the US West Coast,particularly Southern California,from January 7 to 31,2025.The fires were exacerbated by drought conditions,low humidity,accumulated vegetation from the previous winter,and hurricane-force Santa Ana winds,which in some areas reached speeds of 45 m/s.The wildfires claimed at least 30 lives,forced over 200,000 people to evacuate,destroyed more than 18,000 homes and structures,and burned approximately 233 km^(2)of land in total(Wikipedia,2025).展开更多
In the context of global warming, the increasing wildfire frequency has become a critical climate research focus in North America. This study used the Community Earth System Model(CESM 1.2) to investigate the impacts ...In the context of global warming, the increasing wildfire frequency has become a critical climate research focus in North America. This study used the Community Earth System Model(CESM 1.2) to investigate the impacts of 20thcentury wildfires on North American climate and hydrology. Summer represents the peak wildfire season in North America, with the Gulf of Mexico and Midwest regions experiencing the most severe effects. Wildfires not only damage vegetation during the fire season but also extend prolonged impacts into non-fire periods, showing distinct seasonal variations. In spring, wildfires increase surface albedo, triggering a cooling effect through enhanced snow cover and delayed snowmelt. Conversely, summer and autumn surface warming stems primarily from wildfire-suppressed vegetation transpiration. Warming near the Gulf of Mexico enhances moisture transport and precipitation, particularly in summer and autumn. Reduced evaporation and increased precipitation from the Gulf of Mexico significantly altered the hydrological cycle across North America, leading to increased runoff continent-wide.展开更多
The primary objective of this paper is to present a comprehensive case study on monitoring wildfires in Nakhon Nayok, Thailand, utilizing Earth observation platforms. This initiative project has been undertaken by the...The primary objective of this paper is to present a comprehensive case study on monitoring wildfires in Nakhon Nayok, Thailand, utilizing Earth observation platforms. This initiative project has been undertaken by the Excellence Center of Space Technology and Research (ECSTAR), in partnership with its spin-off startup, TeroSpace. The study aims to provide an in-depth analysis of the wildfire incidents in the region, utilizing advanced technologies such as satellite imagery and data analytics, and to identify ways to improve future wildfire management. In particular, the paper focuses on the wildfires including thermal area comparison that ravaged the land in Nakhon Nayok Province in central Thailand from March to April 18th, 2023. To conduct this study, the ECSTAR-TeroSpace analytic team utilized satellite images from Earth observation platforms: MODIS and Sentinel-2A. By presenting this case study, this paper contributes to the broader understanding of how to monitor and manage wildfires in a changing climate. The findings of this study underscore the importance of proactive and collaborative efforts in mitigating the negative impacts of wildfires in Nakhon Nayok and other regions in Thailand.展开更多
Fires play an essential part in the maintenance of the environment, but amplified fire activity often leads to adverse effects in the environment such as destruction of property and loss of life. Botswana has experien...Fires play an essential part in the maintenance of the environment, but amplified fire activity often leads to adverse effects in the environment such as destruction of property and loss of life. Botswana has experienced wildfires that are caused by humans intentionally and unintentionally. Some of these wildfires grow into mega</span><span style="font-family:""> </span><span style="font-family:Verdana;">fires such as the 2008 wildfires. Data of wildfires reported in Botswana from the Department of Forestry and Range Resources and the frequency of occurrence was studied and analyzed. It shows the period of 2006-2017, Ghanzi and Ngamiland districts were mostly affected by wildfires. These districts have protected land such as the wildlife parks which may lead to </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">outbreak of natural wildfires that burns unnoticed due to minimal movements of people. The wildfires reported in each district show an increase over the years and this may affect the smooth running of operations.展开更多
The coal-bearing strata in the southern Junggar Basin in northwestern China have recently attracted the attention of coal geologists. Its abundance of coal resources is of great interest as there is a potential of unl...The coal-bearing strata in the southern Junggar Basin in northwestern China have recently attracted the attention of coal geologists. Its abundance of coal resources is of great interest as there is a potential of unlocking details about the palaeoclimatic information. Coal deposits have the capacity to record wildfire events, even those with inefficient combustions. To characterize wildfire events and palaeoclimatic history of the Middle Jurassic Xishanyao Formation(Aalenian and Bajocian ages), 22 coal samples from borehole cores and coal mines in the southern Junggar Basin were collected and their macerals were analyzed. The results indicated that fusinite and semi-fusinite were the dominant components of inertinite with proportions of 35.27% and 54.67%, respectively. The presence of inertinite is an indicator that wildfires occurred at the time of peat land development, and the widespread occurrence suggests large scale wildfires during the Middle Jurassic. This study proposes a new parameter for the evaluation of wildfire features by combining burning frequency and burning temperature. The comprehensive evaluation index(CEI) was influenced by the lacustrine basin level and ancient plant types from a sequence framework. During the Middle Jurassic, most wildfires were surface fires with low level and ground fire with high level. High oxygen levels were estimated in the lower, middle, and upper members of the Xishanyao Formation with corresponding to 26.78%, 24.55%, and 23.55%, respectively. The high oxygen levels would be the primary cause of repeated wildfires in the Middle Jurassic. These results are helpful for understanding palaeoclimatic changes in the Middle Jurassic.展开更多
Charcoal is abundant in most post-Silurian sedimentary sequences and even in some volcanic rocks. The study of charcoal can provide important information on not only what plants were being burned but also on how the c...Charcoal is abundant in most post-Silurian sedimentary sequences and even in some volcanic rocks. The study of charcoal can provide important information on not only what plants were being burned but also on how the charcoal residue was formed. Most charcoal encountered in the sedimentary record is a result of lightning-ignited wildfires but volcanic activity may also act as an ignition source. Charcoal preserves exquisite anatomical data that can be studied by a range of microscopical techniques including scanning electron microscopy that allows the identity of the plants to be determined. Fires have a major impact on a range of environments and ecosystems. The elevated oxygen content of the atmosphere indicates that the Cretaceous can be considered a "high-fire" world. Fire activity should be taken into account in Cretaceous vegetation and climate models. The occurrence of charcoal at the Cretaceous-Tertiary Boundary has been highlighted as evidence for a global fire following an asteroid impact, but this interpretation is questionable.Charcoal may be found within volcanic rocks, especially from deposits of pyroclastic flows and from basaltic lavas. This may provide data on the entombed vegetation but reflectance data may be used to provide interpretations of deposit temperatures. Charcoal is information-rich but yet is an under-utilized resource. Fire is an expression of life on Earth and an index of life's history and is relevant for geology, biology, human history, physics and global chemistry.展开更多
The Santa Cruz Mountain range in northern California is a coastal landscape with a history of extensive forest logging and frequent large wildfires that have recently destroyed numerous residential structures at the w...The Santa Cruz Mountain range in northern California is a coastal landscape with a history of extensive forest logging and frequent large wildfires that have recently destroyed numerous residential structures at the wildland interface. Results from Landsat satellite image time-series analysis since 1984 of the study area within the Los Gatos Creek and Corralitos Creek watersheds showed that none of the severe drought periods since the 1980s have notably inhibited rapid tree and shrub regrowth rates on steep hill slopes burned recently by the 1985 Lexington Fire and the 2008 Summit Fire. In high burn severity areas of both fires, post-fire vegetation types showed a marked increase in shrub cover, mainly at the expense of evergreen tree cover. Most of these low (<3 m), dense stands of evergreen woody species have regenerated in as little as five years from bare charred ground. A combination of Landsat and Laser Altimeter (GLAS) satellite sensor data revealed that exposed south-facing slopes are presently supporting 200 to 240 Mg·ha<sup>-1</sup> of standing woody biomass on the burned areas. This study is the first of its kind to utilize a full 30-year record of Landsat vegetation index data to monitor tree and shrub regrowth after stand-replacing wildfires in California.展开更多
This study investigated the relationship between climate and biophysical variables in burned areas in Iran.The fire burned area(FBA)product(Fire CCI 5.1.1),land surface temperature(MOD11C3C),vegetation index(MOD13A1),...This study investigated the relationship between climate and biophysical variables in burned areas in Iran.The fire burned area(FBA)product(Fire CCI 5.1.1),land surface temperature(MOD11C3C),vegetation index(MOD13A1),and climate variables such as temperature,wind speed,relative humidity,and volumetric soil moisture from the ERA5 reanalysis dataset were used.Pearson correlation coefficient was used to determine the relationship between biophysical and climate variables and fire occurrence.The results show that FBA increased by 1.7 hectares/decade from 2001 to 2020.The high FBA in 2010(the black summer of Iran)was due to high temperatures and significant heatwaves that led to extensive wildfires.Although anthropogenic activities are considered a significant cause of wildfires,several variables,including increased temperatures,less precipitation,relative humidity,and wind speed and direction,contribute to the extent and occurrence of wildfires.The country’s FBA hotspot is in the Arasbaran region during the summer season.Temperature and relative humidity are the most significant variables influencing the occurrence of wildfires.The results show the vulnerability of Iran s forests and their high potential for fires.Considering the frequency of fire occurrences in Iran and the limited equipment,fire prevention plans should be carried out by applying proper management in high-risk regions.展开更多
The relationship between climate change and wildfires was examined to summarize factors associated with vulnerability to wildfires. The complex and cyclic nature of interaction effects between the two was highlighted ...The relationship between climate change and wildfires was examined to summarize factors associated with vulnerability to wildfires. The complex and cyclic nature of interaction effects between the two was highlighted and the following conclusions were drawn. Climate change is leading to more frequent wildfires with higher intensity, resulting in release of more gasses and particulate matter that further exacerbates the progression of climate change. Direct and indirect impacts are detailed in the main body. A new fire management policy is deemed necessary, with a more local approach being recommended. Human impacts were found to further complicate the already complex relationship. It is recommended to treat accidental and incendiary fires separately for the purpose of evaluating fire management regimes. This requires successful advances in current fire investigation techniques.展开更多
Rapid recovery of pioneer shrub and forest patch cover can reduce soil erosion, nutrient runoff and degradation of stream habitats, and promote small mammal and avian biodiversity following stand-replacing wildfires. ...Rapid recovery of pioneer shrub and forest patch cover can reduce soil erosion, nutrient runoff and degradation of stream habitats, and promote small mammal and avian biodiversity following stand-replacing wildfires. Landsat imagery from the past 25+ years was analyzed to understand patterns and rates of vegetation recovery, focusing on high burn severity (HBS) patches, within wildfire areas dating from the late 1940s in the Sierra-Nevada region of California. Normalized difference vegetation index (NDVI) levels indicative of recovered woody cover within HBS areas were analyzed starting in 1985 to quantify regrowth of patch dynamics. Analysis of landscape metrics showed that the percentage of total HBS area comprised by the largest patch of recovered woody cover was relatively small in all fires that occurred since 1995, but increased rapidly with time since fire. Patch complexity of recovered woody cover decreased notably after more than 50 years of regrowth, but was not readily associated with time for fires that occurred since the mid 1990s. Patch complexity of dense woody cover was consistently high in fires after 1995 and increased with the elevation of HBS areas. The aggregation level of patches with recovery of woody cover increased steadily with time since fire. The study approach using satellite remote sensing can be expanded to assess the consequences of stand-replacing wildfires in all forests of the region.展开更多
Evaluated Weather Research and Forecasting model inline with chemistry (WRF/Chem) simulations of the 2009 Crazy Mountain Complex wildfire in Interior Alaska served as a testbed for typical Alaska wildfire-smoke condit...Evaluated Weather Research and Forecasting model inline with chemistry (WRF/Chem) simulations of the 2009 Crazy Mountain Complex wildfire in Interior Alaska served as a testbed for typical Alaska wildfire-smoke conditions. A virtual unmanned air vehicle (UAV) sampled temperatures, dewpoint temperatures, primary inert and reactive gases and particular matter of different sizes as well as secondary pollutants from the WRF/Chem results using different sampling patterns, altitudes and speeds to investigate the impact of the sampling design on obtained mean distributions. In this experimental design, the WRF/Chem data served as the “grand truth” to assess the mean distributions from sampling. During frontal passage, the obtained mean distributions were sensitive to the flight patterns, speeds and heights. For inert constituents mean distributions from sampling agreed with the “grand truth” within a factor of two at 1000 m. Mean distributions of gases involved in photochemistry differed among flight patterns except for ozone. The diurnal cycle of these gases’ concentrations led to overestimation (underestimation) of 20 h means in areas of high (low) concentrations as compared to the “grand truth.” The mean ozone distribution was sensitive to the speed of the virtual UAV. Particulate matter showed the strongest sensitivity to the flight patterns, especially during precipitation.展开更多
Along with intensified Global warming, wildfires in the midhigh latitudes of the Northern Hemisphere (NH) have exhibited an increasing trend (Running 2006;Abatzoglou et al.,2021;Luo et al., 2024), which led to increas...Along with intensified Global warming, wildfires in the midhigh latitudes of the Northern Hemisphere (NH) have exhibited an increasing trend (Running 2006;Abatzoglou et al.,2021;Luo et al., 2024), which led to increased emissions of Carbon dioxide (CO_(2)) and Fine Particulate Matter with a diameter less than 2.5 micrometers (μm)(PM_(2.5))(Zheng et al., 2023;Zhu et al., 2024;Jain et al., 2024). In particular,enhanced PM_(2.5) emissions have caused a large increase in respiratory disease cases (Zhang Y et al., 2025) and resulted in amplified human health risks and health burdens (Zhao et al., 2025).展开更多
Strongly affected by the escalating impacts of climate change,wildfires have been increasing in frequency and severity around the world.The primary aim of this study was the development of specific territorial measure...Strongly affected by the escalating impacts of climate change,wildfires have been increasing in frequency and severity around the world.The primary aim of this study was the development of specific territorial measures—estimating the optimal locations of firefighting resources—to enhance the spatial resilience to wildfires in the fire-prone region of Chalkidiki Prefecture in northern Greece.These measures focus on the resistance to wildfires and the adaptation of strategies to wildfire management,based on the estimation of burn probability,including the effect of anthropogenic factors on fire ignition.The proposed location schemes of firefighting resources such as vehicles consider both the susceptibility to fire and the influence of the topography on travel simulation,highlighting the impact of road slope on the initial firefighting attack.The spatial scheme,as well as the number of required firefighting forces is totally differentiated due to slope impact.When we ignore the topography effect,a minimum number of fire vehicles is required to achieve the maximization of coverage(99.2%of the entire study area)giving priority to the most susceptible regions(that is,employing 18 of 24 available fire vehicles).But when we adopt more realistic conditions that integrate the slope effect with travel time,the model finds an optimal solution that requires more resources(that is,employing all 24 available fire vehicles)to maximize the coverage of the most vulnerable regions within 27 min.This process achieves 80%of total coverage.The proposed methodology is characterized by a high degree of flexibility,and provides optimized solutions to decision makers,while considering key factors that greatly affect the effectiveness of the initial firefighting attack.展开更多
Inertinite maceral compositions in coals from the Early Cretaceous Erlian, Hailar, and Sanjiang Basins in NE China are analyzed in order to reveal palaeowildfire events and palaeoclimate variations. Although huminite ...Inertinite maceral compositions in coals from the Early Cretaceous Erlian, Hailar, and Sanjiang Basins in NE China are analyzed in order to reveal palaeowildfire events and palaeoclimate variations. Although huminite is the dominant maceral group in the studied basins, the inertinite group, as a byproduct of palaeowildfires, makes up a considerable proportion. Occurrence of inertinite macerals indicates that wildfires were widespread and frequent,and supports the opinion that the Early Cretaceous was a "high-fire" interval. Inertinite contents vary from 0.2% to 85.0%, mostly within the range of 10%–45%, and a model-based calculation suggests that the atmospheric oxygen levels during the Aptian and Albian(Early Cretaceous) were around 24.7% and 25.3% respectively. Frequent fire activity during Early Cretaceous has been previously related to higher atmospheric oxygen concentrations. The inertinite reflectance, ranging from 0.58%Ro to 2.00%Ro, indicates that the palaeowildfire in the Early Cretaceous was dominated by ground fires, partially reaching-surface fires. These results further support that the Cretaceous earliest angiosperms from NE China were growing in elevated O2 conditions compared to the present day.展开更多
The Cretaceous has been considered a“high-fire”world accompanied by widespread by-products of combustion in the rock record.The mid-Cretaceous oceanic anoxic event 1b(OAE1b)is marked by one of the major perturbation...The Cretaceous has been considered a“high-fire”world accompanied by widespread by-products of combustion in the rock record.The mid-Cretaceous oceanic anoxic event 1b(OAE1b)is marked by one of the major perturbations in the global carbon cycle characterized by deposition of organic-rich sediments in both marine and terrestrial settings.However,our understanding is still limited on changes in wildfire activity during OAE1b period.Here,we carried out a comprehensive analysis,including organic carbon isotope(δ^(13)C_(org)),total organic carbon(TOC),coal petrology,trace elements,and pyrolytic polycyclic aromatic hydrocarbons(pyroPAHs),of coal seams of the middle Aptian to early Albian Shahezi Formation from borehole SK-2 in Songliao Basin,Northeast China.Two negativeδ^(13)C_(org) excursions in the Shahezi Formation can be corresponded with the 113/Jacob and Kilian sub-events of OAE1b.Moreover,the intensive peatland wildfires have been identified during the sub-event periods of OAE1b based on the co-occurrence of high abundance of charcoal and pyroPAHs at that time.In addition,Sr/Ba,Sr/Cu and Sr/Rb ratios demonstrate that enhanced peatland wildfires were controlled by dryer climate conditions owing to episodic northward migration of arid zones in East Asia related with rising global temperature during the sub-events of OAE1b.The climate-driven extensive wildfire activity in the mid-latitude terrestrial ecosystems can be a contributing factor for OAE1b through the increased flux of nutrients fuelling primary producers in the lake and marine environments and leading to more speculative anoxia to allow the deposition of organic-rich sediments.Our results provide essential understanding of the importance of wildfires in driving mechanism of oceanic anoxic events(OAEs)in Earth's history.展开更多
The Upper Cretaceous(early Cenomanian)Bahariya Formation of Egypt has an outstanding reputation for its wealth of vertebrate remains,including a variety of iconic dinosaurs,like the carnivorous Spinosaurus and Carchar...The Upper Cretaceous(early Cenomanian)Bahariya Formation of Egypt has an outstanding reputation for its wealth of vertebrate remains,including a variety of iconic dinosaurs,like the carnivorous Spinosaurus and Carcharodontosaurus,as well as the herbivorous Aegyptosaurus and Paralititan.Besides these dinosaur fossils,the Bahariya Formation yielded also a wealth of invertebrate and plant remains,but even today many aspects concerning the continental palaeoenvironments reflected in these deposits(including the occurrence of palaeo-wildfires)have not been studied in detail.So far six distinct macro-charcoal bearing levels could be identified within the type section of the Bahariya Formation at Gabal El Dist profile,one of the most prolific outcrops of this formation in terms of fossil occurrence located in the north of the Bahariya Oasis,Western Desert,Egypt.Most of the charcoal investigated by means of SEM originates from ferns,pointing to a considerable proportion of this plant group within the palaeo-ecosystems that experienced fires.Gymnosperms and(putative)angiosperms have less frequently been identified.The collected data present evidence that the landscapes at the northern shores of Gondwana repeatedly experienced palaeo-wildfires,adding extra proof to previous statements that the Late Cretaceous was a fiery world on a global scale.展开更多
Data processing and climate characterisation to study its impact is becoming difficult due to insufficient and unavailable data,especially in developing countries.Understanding climate’s impact on burnt areas in Ghan...Data processing and climate characterisation to study its impact is becoming difficult due to insufficient and unavailable data,especially in developing countries.Understanding climate’s impact on burnt areas in Ghana(Guinea-savannah(GSZ)and Forest-savannah Mosaic zones(FSZ))leads us to opt for machine learning.Through Google Earth Engine(GEE),rainfall(PR),maximum temperature(Tmax),minimum temperature(Tmin),average temperature(Tmean),Palmer Drought Severity Index(PDSI),relative humidity(RH),wind speed(WS),soil moisture(SM),actual evapotranspiration(ETA)and reference evapotranspiration(ETR)have been acquired through CHIRPS(Climate Hazards group Infrared Precipitation with Stations),FLDAS dataset(Famine Early Warning Systems Network(FEWS NET)Land Data Assimilation System)and TerraClimate platform from 1991 to 2021.The objective is to analyse the link and the contribution of climatic and environmental parameters on wildfire spread in GSZ and FSZ in Ghana.Variables were analysed(area burnt and the number of activefires)through Spearman correlation and the cross-correlation function(CCF)(2001 to 2021).The tests(Mann-Kendall and Sens’s slope trend test,Pettitt test and the Lee and Heghinian test)showed the overall decrease in rainfall and increase in temperature respectively(-0.1 mm;+0.8℃)in GSZ and(-0.9 mm;+0.3℃)in FSZ.In terms of impact,PR,ETR,FDI,Tmean,Tmax,Tmin,RH,ETA and SM contribute tofire spread.Through the codes developed,researchers and decision-makers could update them at different times easily to monitor climate variability and its impact onfires.展开更多
Charcoals collected from the middle-late Pliocene sediments of the Taigu Basin,Shanxi Province,China,have been identified as Ulmus sp.(Ulmaceae),Prunus sp.,Maloidoxylon sp.(Rosaceae),and Maclura sp.(Moraceae).These ta...Charcoals collected from the middle-late Pliocene sediments of the Taigu Basin,Shanxi Province,China,have been identified as Ulmus sp.(Ulmaceae),Prunus sp.,Maloidoxylon sp.(Rosaceae),and Maclura sp.(Moraceae).These taxa,along with the previously known fossils,indicate the occurrence of temperate climate and local wildfire at that time.Charcoals of trees and/or shrubs and the morphological changes of these charcoals demonstrate that crown fires and surface fires occurred in the Taigu Basin during the middle-late Pliocene.展开更多
Wildfire events have recently shown a rapid increase in frequency and scale due to the warmer present-day climate;however,their potential effects on the cryosphere are difficult to assess.Catastrophic wildfires in Aus...Wildfire events have recently shown a rapid increase in frequency and scale due to the warmer present-day climate;however,their potential effects on the cryosphere are difficult to assess.Catastrophic wildfires in Australia during 2019–2020 emitted large amounts of light-absorbing particles(LAPs)to the atmosphere.Satellite observations indicate that these LAPs caused unprecedented snow-darkening of glaciers in New Zealand through long-range transport and deposition,with their effects lasting for up to three months in January–March 2020,influencing>90%of total glacier/snow and leading to a mean broadband snow-reflectance reduction of 0.08±0.03.This snow darkening accelerated snowmelt by~0.41±0.2 cm day–1 during the southern summer,equivalent to that caused by a~1.8°C increase in air temperature.This indicates the significant impact of the 2019–2020 Australian wildfires on the hydrologic cycle in New Zealand,exceeding that of the local climate warming of~1.5°C since the preindustrial period.Wildfire-induced snow darkening is not limited to New Zealand.Future projections of wildfire incidence indicate widespread effects of snow darkening on the global cryosphere.展开更多
文摘Years after wildfires burn forests and watersheds(分水岭)in the Western US,pollutants left behind continue to poison rivers and streams,and have existed for a longer time than scientists previously estimated.
基金The National Natural Science Foundation of China under contract Nos 42430107 and 42476176.
文摘A series of 14 destructive wildfires swept across the US West Coast,particularly Southern California,from January 7 to 31,2025.The fires were exacerbated by drought conditions,low humidity,accumulated vegetation from the previous winter,and hurricane-force Santa Ana winds,which in some areas reached speeds of 45 m/s.The wildfires claimed at least 30 lives,forced over 200,000 people to evacuate,destroyed more than 18,000 homes and structures,and burned approximately 233 km^(2)of land in total(Wikipedia,2025).
基金National Natural Science Foundation of China(42175022)。
文摘In the context of global warming, the increasing wildfire frequency has become a critical climate research focus in North America. This study used the Community Earth System Model(CESM 1.2) to investigate the impacts of 20thcentury wildfires on North American climate and hydrology. Summer represents the peak wildfire season in North America, with the Gulf of Mexico and Midwest regions experiencing the most severe effects. Wildfires not only damage vegetation during the fire season but also extend prolonged impacts into non-fire periods, showing distinct seasonal variations. In spring, wildfires increase surface albedo, triggering a cooling effect through enhanced snow cover and delayed snowmelt. Conversely, summer and autumn surface warming stems primarily from wildfire-suppressed vegetation transpiration. Warming near the Gulf of Mexico enhances moisture transport and precipitation, particularly in summer and autumn. Reduced evaporation and increased precipitation from the Gulf of Mexico significantly altered the hydrological cycle across North America, leading to increased runoff continent-wide.
文摘The primary objective of this paper is to present a comprehensive case study on monitoring wildfires in Nakhon Nayok, Thailand, utilizing Earth observation platforms. This initiative project has been undertaken by the Excellence Center of Space Technology and Research (ECSTAR), in partnership with its spin-off startup, TeroSpace. The study aims to provide an in-depth analysis of the wildfire incidents in the region, utilizing advanced technologies such as satellite imagery and data analytics, and to identify ways to improve future wildfire management. In particular, the paper focuses on the wildfires including thermal area comparison that ravaged the land in Nakhon Nayok Province in central Thailand from March to April 18th, 2023. To conduct this study, the ECSTAR-TeroSpace analytic team utilized satellite images from Earth observation platforms: MODIS and Sentinel-2A. By presenting this case study, this paper contributes to the broader understanding of how to monitor and manage wildfires in a changing climate. The findings of this study underscore the importance of proactive and collaborative efforts in mitigating the negative impacts of wildfires in Nakhon Nayok and other regions in Thailand.
文摘Fires play an essential part in the maintenance of the environment, but amplified fire activity often leads to adverse effects in the environment such as destruction of property and loss of life. Botswana has experienced wildfires that are caused by humans intentionally and unintentionally. Some of these wildfires grow into mega</span><span style="font-family:""> </span><span style="font-family:Verdana;">fires such as the 2008 wildfires. Data of wildfires reported in Botswana from the Department of Forestry and Range Resources and the frequency of occurrence was studied and analyzed. It shows the period of 2006-2017, Ghanzi and Ngamiland districts were mostly affected by wildfires. These districts have protected land such as the wildlife parks which may lead to </span><span style="font-family:Verdana;">the </span><span style="font-family:Verdana;">outbreak of natural wildfires that burns unnoticed due to minimal movements of people. The wildfires reported in each district show an increase over the years and this may affect the smooth running of operations.
基金supported by the National Natural Science Foundation of China (4157209042102223)+4 种基金China Postdoctoral Science Foundation (2021M6938442022T150284)the China Geological Survey Project (DD20160204-3)the discipline innovation team of Liaoning Technical University (LNTU20TD-05LNTU20TD-14)。
文摘The coal-bearing strata in the southern Junggar Basin in northwestern China have recently attracted the attention of coal geologists. Its abundance of coal resources is of great interest as there is a potential of unlocking details about the palaeoclimatic information. Coal deposits have the capacity to record wildfire events, even those with inefficient combustions. To characterize wildfire events and palaeoclimatic history of the Middle Jurassic Xishanyao Formation(Aalenian and Bajocian ages), 22 coal samples from borehole cores and coal mines in the southern Junggar Basin were collected and their macerals were analyzed. The results indicated that fusinite and semi-fusinite were the dominant components of inertinite with proportions of 35.27% and 54.67%, respectively. The presence of inertinite is an indicator that wildfires occurred at the time of peat land development, and the widespread occurrence suggests large scale wildfires during the Middle Jurassic. This study proposes a new parameter for the evaluation of wildfire features by combining burning frequency and burning temperature. The comprehensive evaluation index(CEI) was influenced by the lacustrine basin level and ancient plant types from a sequence framework. During the Middle Jurassic, most wildfires were surface fires with low level and ground fire with high level. High oxygen levels were estimated in the lower, middle, and upper members of the Xishanyao Formation with corresponding to 26.78%, 24.55%, and 23.55%, respectively. The high oxygen levels would be the primary cause of repeated wildfires in the Middle Jurassic. These results are helpful for understanding palaeoclimatic changes in the Middle Jurassic.
文摘Charcoal is abundant in most post-Silurian sedimentary sequences and even in some volcanic rocks. The study of charcoal can provide important information on not only what plants were being burned but also on how the charcoal residue was formed. Most charcoal encountered in the sedimentary record is a result of lightning-ignited wildfires but volcanic activity may also act as an ignition source. Charcoal preserves exquisite anatomical data that can be studied by a range of microscopical techniques including scanning electron microscopy that allows the identity of the plants to be determined. Fires have a major impact on a range of environments and ecosystems. The elevated oxygen content of the atmosphere indicates that the Cretaceous can be considered a "high-fire" world. Fire activity should be taken into account in Cretaceous vegetation and climate models. The occurrence of charcoal at the Cretaceous-Tertiary Boundary has been highlighted as evidence for a global fire following an asteroid impact, but this interpretation is questionable.Charcoal may be found within volcanic rocks, especially from deposits of pyroclastic flows and from basaltic lavas. This may provide data on the entombed vegetation but reflectance data may be used to provide interpretations of deposit temperatures. Charcoal is information-rich but yet is an under-utilized resource. Fire is an expression of life on Earth and an index of life's history and is relevant for geology, biology, human history, physics and global chemistry.
文摘The Santa Cruz Mountain range in northern California is a coastal landscape with a history of extensive forest logging and frequent large wildfires that have recently destroyed numerous residential structures at the wildland interface. Results from Landsat satellite image time-series analysis since 1984 of the study area within the Los Gatos Creek and Corralitos Creek watersheds showed that none of the severe drought periods since the 1980s have notably inhibited rapid tree and shrub regrowth rates on steep hill slopes burned recently by the 1985 Lexington Fire and the 2008 Summit Fire. In high burn severity areas of both fires, post-fire vegetation types showed a marked increase in shrub cover, mainly at the expense of evergreen tree cover. Most of these low (<3 m), dense stands of evergreen woody species have regenerated in as little as five years from bare charred ground. A combination of Landsat and Laser Altimeter (GLAS) satellite sensor data revealed that exposed south-facing slopes are presently supporting 200 to 240 Mg·ha<sup>-1</sup> of standing woody biomass on the burned areas. This study is the first of its kind to utilize a full 30-year record of Landsat vegetation index data to monitor tree and shrub regrowth after stand-replacing wildfires in California.
基金supported by a grant from Shahid Beheshti University。
文摘This study investigated the relationship between climate and biophysical variables in burned areas in Iran.The fire burned area(FBA)product(Fire CCI 5.1.1),land surface temperature(MOD11C3C),vegetation index(MOD13A1),and climate variables such as temperature,wind speed,relative humidity,and volumetric soil moisture from the ERA5 reanalysis dataset were used.Pearson correlation coefficient was used to determine the relationship between biophysical and climate variables and fire occurrence.The results show that FBA increased by 1.7 hectares/decade from 2001 to 2020.The high FBA in 2010(the black summer of Iran)was due to high temperatures and significant heatwaves that led to extensive wildfires.Although anthropogenic activities are considered a significant cause of wildfires,several variables,including increased temperatures,less precipitation,relative humidity,and wind speed and direction,contribute to the extent and occurrence of wildfires.The country’s FBA hotspot is in the Arasbaran region during the summer season.Temperature and relative humidity are the most significant variables influencing the occurrence of wildfires.The results show the vulnerability of Iran s forests and their high potential for fires.Considering the frequency of fire occurrences in Iran and the limited equipment,fire prevention plans should be carried out by applying proper management in high-risk regions.
文摘The relationship between climate change and wildfires was examined to summarize factors associated with vulnerability to wildfires. The complex and cyclic nature of interaction effects between the two was highlighted and the following conclusions were drawn. Climate change is leading to more frequent wildfires with higher intensity, resulting in release of more gasses and particulate matter that further exacerbates the progression of climate change. Direct and indirect impacts are detailed in the main body. A new fire management policy is deemed necessary, with a more local approach being recommended. Human impacts were found to further complicate the already complex relationship. It is recommended to treat accidental and incendiary fires separately for the purpose of evaluating fire management regimes. This requires successful advances in current fire investigation techniques.
文摘Rapid recovery of pioneer shrub and forest patch cover can reduce soil erosion, nutrient runoff and degradation of stream habitats, and promote small mammal and avian biodiversity following stand-replacing wildfires. Landsat imagery from the past 25+ years was analyzed to understand patterns and rates of vegetation recovery, focusing on high burn severity (HBS) patches, within wildfire areas dating from the late 1940s in the Sierra-Nevada region of California. Normalized difference vegetation index (NDVI) levels indicative of recovered woody cover within HBS areas were analyzed starting in 1985 to quantify regrowth of patch dynamics. Analysis of landscape metrics showed that the percentage of total HBS area comprised by the largest patch of recovered woody cover was relatively small in all fires that occurred since 1995, but increased rapidly with time since fire. Patch complexity of recovered woody cover decreased notably after more than 50 years of regrowth, but was not readily associated with time for fires that occurred since the mid 1990s. Patch complexity of dense woody cover was consistently high in fires after 1995 and increased with the elevation of HBS areas. The aggregation level of patches with recovery of woody cover increased steadily with time since fire. The study approach using satellite remote sensing can be expanded to assess the consequences of stand-replacing wildfires in all forests of the region.
基金The National Aeronautics and Space Administration provided funding(Grant NASA-NNX11AQ27A).
文摘Evaluated Weather Research and Forecasting model inline with chemistry (WRF/Chem) simulations of the 2009 Crazy Mountain Complex wildfire in Interior Alaska served as a testbed for typical Alaska wildfire-smoke conditions. A virtual unmanned air vehicle (UAV) sampled temperatures, dewpoint temperatures, primary inert and reactive gases and particular matter of different sizes as well as secondary pollutants from the WRF/Chem results using different sampling patterns, altitudes and speeds to investigate the impact of the sampling design on obtained mean distributions. In this experimental design, the WRF/Chem data served as the “grand truth” to assess the mean distributions from sampling. During frontal passage, the obtained mean distributions were sensitive to the flight patterns, speeds and heights. For inert constituents mean distributions from sampling agreed with the “grand truth” within a factor of two at 1000 m. Mean distributions of gases involved in photochemistry differed among flight patterns except for ozone. The diurnal cycle of these gases’ concentrations led to overestimation (underestimation) of 20 h means in areas of high (low) concentrations as compared to the “grand truth.” The mean ozone distribution was sensitive to the speed of the virtual UAV. Particulate matter showed the strongest sensitivity to the flight patterns, especially during precipitation.
基金supported by the National Natural Science Foundation of China (Grant No.42288101)。
文摘Along with intensified Global warming, wildfires in the midhigh latitudes of the Northern Hemisphere (NH) have exhibited an increasing trend (Running 2006;Abatzoglou et al.,2021;Luo et al., 2024), which led to increased emissions of Carbon dioxide (CO_(2)) and Fine Particulate Matter with a diameter less than 2.5 micrometers (μm)(PM_(2.5))(Zheng et al., 2023;Zhu et al., 2024;Jain et al., 2024). In particular,enhanced PM_(2.5) emissions have caused a large increase in respiratory disease cases (Zhang Y et al., 2025) and resulted in amplified human health risks and health burdens (Zhao et al., 2025).
基金This scientific publication took place within the framework of the project “Grant for Post-Doctoral Research” of the University of Thessaly, which is being implemented by the University of Thessaly and financed by the Stavros Niarchos Foundation
文摘Strongly affected by the escalating impacts of climate change,wildfires have been increasing in frequency and severity around the world.The primary aim of this study was the development of specific territorial measures—estimating the optimal locations of firefighting resources—to enhance the spatial resilience to wildfires in the fire-prone region of Chalkidiki Prefecture in northern Greece.These measures focus on the resistance to wildfires and the adaptation of strategies to wildfire management,based on the estimation of burn probability,including the effect of anthropogenic factors on fire ignition.The proposed location schemes of firefighting resources such as vehicles consider both the susceptibility to fire and the influence of the topography on travel simulation,highlighting the impact of road slope on the initial firefighting attack.The spatial scheme,as well as the number of required firefighting forces is totally differentiated due to slope impact.When we ignore the topography effect,a minimum number of fire vehicles is required to achieve the maximization of coverage(99.2%of the entire study area)giving priority to the most susceptible regions(that is,employing 18 of 24 available fire vehicles).But when we adopt more realistic conditions that integrate the slope effect with travel time,the model finds an optimal solution that requires more resources(that is,employing all 24 available fire vehicles)to maximize the coverage of the most vulnerable regions within 27 min.This process achieves 80%of total coverage.The proposed methodology is characterized by a high degree of flexibility,and provides optimized solutions to decision makers,while considering key factors that greatly affect the effectiveness of the initial firefighting attack.
基金funded by the National Science and Technology Major Project(2016ZX05041004–003)the Yue Qi Scholar Project of China University of Mining and Technology(Beijing)+1 种基金the Central University Fundamental Research Fund(2010YD09)These funds help to the design of the study and collection,analysis,and interpretation of data
文摘Inertinite maceral compositions in coals from the Early Cretaceous Erlian, Hailar, and Sanjiang Basins in NE China are analyzed in order to reveal palaeowildfire events and palaeoclimate variations. Although huminite is the dominant maceral group in the studied basins, the inertinite group, as a byproduct of palaeowildfires, makes up a considerable proportion. Occurrence of inertinite macerals indicates that wildfires were widespread and frequent,and supports the opinion that the Early Cretaceous was a "high-fire" interval. Inertinite contents vary from 0.2% to 85.0%, mostly within the range of 10%–45%, and a model-based calculation suggests that the atmospheric oxygen levels during the Aptian and Albian(Early Cretaceous) were around 24.7% and 25.3% respectively. Frequent fire activity during Early Cretaceous has been previously related to higher atmospheric oxygen concentrations. The inertinite reflectance, ranging from 0.58%Ro to 2.00%Ro, indicates that the palaeowildfire in the Early Cretaceous was dominated by ground fires, partially reaching-surface fires. These results further support that the Cretaceous earliest angiosperms from NE China were growing in elevated O2 conditions compared to the present day.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.42102127,42172117,41772096)the Natural Science Foundation of Shandong Province(Grant No.ZR2021QD087)+1 种基金the Chinese Postdoctoral Science Foundation(Grant No.2021M702019)the SDUST Research Fund,Shandong University of Science and Technology(Grant No.2018TDJH101)。
文摘The Cretaceous has been considered a“high-fire”world accompanied by widespread by-products of combustion in the rock record.The mid-Cretaceous oceanic anoxic event 1b(OAE1b)is marked by one of the major perturbations in the global carbon cycle characterized by deposition of organic-rich sediments in both marine and terrestrial settings.However,our understanding is still limited on changes in wildfire activity during OAE1b period.Here,we carried out a comprehensive analysis,including organic carbon isotope(δ^(13)C_(org)),total organic carbon(TOC),coal petrology,trace elements,and pyrolytic polycyclic aromatic hydrocarbons(pyroPAHs),of coal seams of the middle Aptian to early Albian Shahezi Formation from borehole SK-2 in Songliao Basin,Northeast China.Two negativeδ^(13)C_(org) excursions in the Shahezi Formation can be corresponded with the 113/Jacob and Kilian sub-events of OAE1b.Moreover,the intensive peatland wildfires have been identified during the sub-event periods of OAE1b based on the co-occurrence of high abundance of charcoal and pyroPAHs at that time.In addition,Sr/Ba,Sr/Cu and Sr/Rb ratios demonstrate that enhanced peatland wildfires were controlled by dryer climate conditions owing to episodic northward migration of arid zones in East Asia related with rising global temperature during the sub-events of OAE1b.The climate-driven extensive wildfire activity in the mid-latitude terrestrial ecosystems can be a contributing factor for OAE1b through the increased flux of nutrients fuelling primary producers in the lake and marine environments and leading to more speculative anoxia to allow the deposition of organic-rich sediments.Our results provide essential understanding of the importance of wildfires in driving mechanism of oceanic anoxic events(OAEs)in Earth's history.
基金support by Coordenadoria de Aperfeicoamento de Pessoal de Nível Superior-CAPES(A072/2013 and 8107-14-9)Conselho Nacional de Desenvolvimento Científico e Tecnológico-CNPq(444330/2014-3,305436/2015-5)Brazil and Alexander von Humboldt Foundation(3.4-8151/18 025),Germany
文摘The Upper Cretaceous(early Cenomanian)Bahariya Formation of Egypt has an outstanding reputation for its wealth of vertebrate remains,including a variety of iconic dinosaurs,like the carnivorous Spinosaurus and Carcharodontosaurus,as well as the herbivorous Aegyptosaurus and Paralititan.Besides these dinosaur fossils,the Bahariya Formation yielded also a wealth of invertebrate and plant remains,but even today many aspects concerning the continental palaeoenvironments reflected in these deposits(including the occurrence of palaeo-wildfires)have not been studied in detail.So far six distinct macro-charcoal bearing levels could be identified within the type section of the Bahariya Formation at Gabal El Dist profile,one of the most prolific outcrops of this formation in terms of fossil occurrence located in the north of the Bahariya Oasis,Western Desert,Egypt.Most of the charcoal investigated by means of SEM originates from ferns,pointing to a considerable proportion of this plant group within the palaeo-ecosystems that experienced fires.Gymnosperms and(putative)angiosperms have less frequently been identified.The collected data present evidence that the landscapes at the northern shores of Gondwana repeatedly experienced palaeo-wildfires,adding extra proof to previous statements that the Late Cretaceous was a fiery world on a global scale.
文摘Data processing and climate characterisation to study its impact is becoming difficult due to insufficient and unavailable data,especially in developing countries.Understanding climate’s impact on burnt areas in Ghana(Guinea-savannah(GSZ)and Forest-savannah Mosaic zones(FSZ))leads us to opt for machine learning.Through Google Earth Engine(GEE),rainfall(PR),maximum temperature(Tmax),minimum temperature(Tmin),average temperature(Tmean),Palmer Drought Severity Index(PDSI),relative humidity(RH),wind speed(WS),soil moisture(SM),actual evapotranspiration(ETA)and reference evapotranspiration(ETR)have been acquired through CHIRPS(Climate Hazards group Infrared Precipitation with Stations),FLDAS dataset(Famine Early Warning Systems Network(FEWS NET)Land Data Assimilation System)and TerraClimate platform from 1991 to 2021.The objective is to analyse the link and the contribution of climatic and environmental parameters on wildfire spread in GSZ and FSZ in Ghana.Variables were analysed(area burnt and the number of activefires)through Spearman correlation and the cross-correlation function(CCF)(2001 to 2021).The tests(Mann-Kendall and Sens’s slope trend test,Pettitt test and the Lee and Heghinian test)showed the overall decrease in rainfall and increase in temperature respectively(-0.1 mm;+0.8℃)in GSZ and(-0.9 mm;+0.3℃)in FSZ.In terms of impact,PR,ETR,FDI,Tmean,Tmax,Tmin,RH,ETA and SM contribute tofire spread.Through the codes developed,researchers and decision-makers could update them at different times easily to monitor climate variability and its impact onfires.
基金supported by National Natural Science Foundation of China(Grant Nos.30770148,30990241,30530050,39770046 and 41072022)
文摘Charcoals collected from the middle-late Pliocene sediments of the Taigu Basin,Shanxi Province,China,have been identified as Ulmus sp.(Ulmaceae),Prunus sp.,Maloidoxylon sp.(Rosaceae),and Maclura sp.(Moraceae).These taxa,along with the previously known fossils,indicate the occurrence of temperate climate and local wildfire at that time.Charcoals of trees and/or shrubs and the morphological changes of these charcoals demonstrate that crown fires and surface fires occurred in the Taigu Basin during the middle-late Pliocene.
基金This research was supported by the National Science Fund for Distinguished Young Scholars(42025102)the Foundation for Innovative Research Groups of the National Natural Science Foundation of China(41521004)the National Natural Science Foundation of China(42075061 and 41975157).
文摘Wildfire events have recently shown a rapid increase in frequency and scale due to the warmer present-day climate;however,their potential effects on the cryosphere are difficult to assess.Catastrophic wildfires in Australia during 2019–2020 emitted large amounts of light-absorbing particles(LAPs)to the atmosphere.Satellite observations indicate that these LAPs caused unprecedented snow-darkening of glaciers in New Zealand through long-range transport and deposition,with their effects lasting for up to three months in January–March 2020,influencing>90%of total glacier/snow and leading to a mean broadband snow-reflectance reduction of 0.08±0.03.This snow darkening accelerated snowmelt by~0.41±0.2 cm day–1 during the southern summer,equivalent to that caused by a~1.8°C increase in air temperature.This indicates the significant impact of the 2019–2020 Australian wildfires on the hydrologic cycle in New Zealand,exceeding that of the local climate warming of~1.5°C since the preindustrial period.Wildfire-induced snow darkening is not limited to New Zealand.Future projections of wildfire incidence indicate widespread effects of snow darkening on the global cryosphere.
