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The Brazilian Amazon, a vital tropical region, faces escalating threats from human activities, agriculture, and climate change. This study aims to assess the relationship between forest fire occurrences, meteorological factors, and hospitalizations due to respiratory diseases in the Legal Amazon region from 2009 to 2019. Employing simultaneous equation models with official data, we examined the association between deforestation-induced fires and respiratory health issues. Over the studied period, the Legal Amazon region recorded a staggering 1,438,322 wildfires, with 1,218,606 (85%) occurring during August-December, known as the forest fire season. During the forest fire season, a substantial portion (566,707) of the total 1,532,228 hospital admissions for respiratory diseases were recorded in individuals aged 0-14 years and 60 years and above. A model consisting of two sets of simultaneous equations was constructed. This model illustrates the seasonal fluctuations in meteorological conditions driving human activities associated with increased forest fires. It also represents how air quality variations impact the occurrence of respiratory diseases during forest fires. This modeling approach unveiled that drier conditions, elevated temperatures, and reduced precipitation exacerbate fire incidents, impacting hospital admissions for respiratory diseases at a rate as high as 22 hospital admissions per 1000 forest fire events during the forest fire season in the Legal Amazon, 2009-2019. This research highlights the urgent need for environmental and health policies to mitigate the effects of Amazon rainforest wildfires, stressing the interplay of deforestation, climate change, and human-induced fires on respiratory health.

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Recent years have seen a rise in wildfire and extreme weather activity across the globe, which is projected to keep increasing with climate-induced conditions. Air pollution, especially fine particulate matter (PM2.5) concentration, is heavily affected by PM2.5 emissions from wildfire activity. Paraguay has been historically suffering from fires, with an average of 2.3 million hectares burnt per year during the 2003-2021 period. Annual PM2.5 concentration in Paraguay is 13.2 µg/m3, more than double the recommended by the WHO. We estimate that, historically, almost 40 % of fine air particulates can be attributed to fires. Using a random forest algorithm, we estimate future fire activity and fire related PM2.5 under different climate change scenarios. With global warming, we calculate that fire activity could increase by up to 120 % by 2100. Annual fire smoke PM2.5 from fires is expected to increase by 7.7 µg/m3 by 2100. Under these conditions, Paraguay is expected to suffer an increase in 3500 deaths per year attributable to fire smoke PM2.5 by 2100. We estimate the economic cost of fire smoke-related mortality by 2100 at US $ 5600 million, equivalent to 2.6 % of Paraguay's GDP, excluding other health- and productivity-related impacts on society.

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The Chilean Climate Change Law excludes tree monocultures as a solution to the climate crisis, offering an opportunity for resilience and climate mitigation in Latin America. The Chilean experience with mega-fires in extensive, homogeneous forest plantations provides important lessons that could inform climate policies in other countries.

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The Chilean matorral is a heavily threatened Mediterranean-type ecosystem due to human-related activities such as anthropogenic fires. Mycorrhizal fungi may be the key microorganisms to help plants cope with environmental stress and improve the restoration of degraded ecosystems. However, the application of mycorrhizal fungi in the restoration of the Chilean matorral is limited because of insufficient local information. Consequently, we assessed the effect of mycorrhizal inoculation on the survival and photosynthesis at set intervals for two years after a fire event in four native woody plant species, namely: Peumus boldus, Quillaja saponaria, Cryptocarya alba, and Kageneckia oblonga, all dominant species of the matorral. Additionally, we assessed the enzymatic activity of three enzymes and macronutrient in the soil in mycorrhizal and non-mycorrhizal plants. The results showed that mycorrhizal inoculation increased survival in all studied species after a fire and increased photosynthesis in all, but not in P. boldus. Additionally, the soil associated with mycorrhizal plants had higher enzymatic activity and macronutrient levels in all species except in Q. saponaria, in which there was no significant mycorrhization effect. The results suggest that mycorrhizal fungi could increase the fitness of plants used in restoration initiatives after severe disturbances such as fires and, consequently, should be considered for restoration programs of native species in threatened Mediterranean ecosystems.

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Background: The Indigenous Kichwa Saraguro people of southern Ecuador have long relied on traditional burning to manage their environment. However, their traditional use of fire in one of the most important ecosystems in southern Ecuador, the herbaceous paramo, is not well known. This lack of knowledge does not allow for the improvement of local regulations related to integrated fire management, which is a shortcoming compared to other regulations applied in South America. In this context, and to understand the impacts of the Indigenous use of fire, a climatic analysis of the area was carried out, generating a historical climograph (period: years 1981-2021) and four annual climographs that were contrasted with a remote sensing study of fire severity over 4 years (years 2018, 2019, 2020, and 2021). In addition, traditional fire use was determined through the application of semi-structured interview questionnaires applied to 61 women and 89 men, whose data were analyzed with the level of information fidelity (LIF), informant consensus factor (ICF), and principal component analysis (PCA). Therefore, in this study, we argue that it is important to incorporate the concepts of (i) wildfire severity and (ii) cultural burning in wildfire policies and regulations in southern Ecuador. Results: The results indicate that low-severity fires occur within the Saraguro territory and that fire use knowledge is transmitted to new generations incorporating both how and where to perform traditional burning. They also know when to burn using the burning calendar that is generally applied during the climatic phenomenon known as "Veranillo del Niño" (VdN). Conclusions: These results can help decision-makers design policies, regulations, and proposals for the correct use of fire as a tool for the management of ecosystems in southern Ecuador affected by wildfires. In addition, the results can be used to improve the National Strategy for Integrated Fire Management 2021-2025 promoted by the Ministry of Environment, Water and Ecological Transition of Ecuador.

Antecedentes: El pueblo indígena de los Kichwa-Saraguro del sur de Ecuador ha confiado en las quemas tradicionales para manejar su ambiente. Sin embargo, su uso tradicional en uno de los ecosistemas más importantes en el sur de Ecuador, el páramo herbáceo, no es bien conocido. Esta falta de conocimiento no permite el mejoramiento de las regulaciones locales relacionadas con el manejo integrado del fuego, lo cual significa una anormalidad comparada con otras regulaciones aplicadas en América del Sur. En este contexto y para entender los impactos del uso indígena del fuego, un análisis climático del área fue llevado a cabo, generando un climograma histórico (desde 1981 a 2021) y cuatro climogramas anuales que fueron contrastados con un estudio de severidad del fuego mediante sensores remotos por cuatro años (2018, 2019, 2020 y 2021). Adicionalmente, el uso tradicional del fuego fue determinado mediante la aplicación de cuestionarios semiestructurados a 61 mujeres y 89 hombres, y cuyos datos fueron analizados mediante la fidelidad del nivel de información (LIF), el factor de consenso del informante (ICF) y un análisis de componentes principales (PCA). Por lo tanto, argüimos que es importante incorporar los conceptos de i) severidad de los incendios y ii) quemas culturales, en las políticas y regulaciones del manejo de fuego en el sur de Ecuador. Resultados: Los resultados indican que los fuegos de baja severidad ocurren dentro del territorio del Saguaro y que el conocimiento sobre el uso del fuego es transmitido a nuevas generaciones incorporando tanto el cómo y el cuándo hacer las quemas tradicionales. Ellos saben también cuándo quemar mediante el uso del calendario de quemas, que es generalmente aplicado durante el fenómeno climático conocido como Veranillo del Niño (VdN). Conclusiones: Estos Resultados pueden ayudar a los decisores a diseñar políticas, regulaciones, y propuesta para el uso del fuego como herramienta de manejo de los ecosistemas del sur de Ecuador afectados por incendios. Adicionalmente, los resultados pueden usarse para mejorar la Estrategia Nacional para el Manejo Integrado del Fuego 2021-2025 promovido por el Ministerio de Ambiente, Agua y Transición Ecológica de Ecuador.

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The advance of human activities in a disorderly way has accelerated in recent decades, intensifying the environmental impacts directly linked to these practices. The atmosphere, essential for the maintenance of life, is increasingly saturated with pollutants, offering risks to practically all the inhabitants of the planet, a process that, in addition to causing illness and early mortality, is related to serious financial losses (including in the production of goods), dangerous temperature increase and severe natural disasters. Although this perception is not recent, the global initiative to control the different mechanisms that trigger the commitment of biodiversity and irreversible climate changes arising from pollution is still very incipient, given that global initiatives on the subject emerged just over 50 years ago. Brazil is a territory that centralizes many of these discussions, as it still faces both political and economic obstacles in achieving a sustainable growth model as it was agreed through the United Nations 2030 Agenda. Even though there is little time left for the completion of these goals, much remains to be done, and despite the fulfillment of this deadline, the works will certainly need to be extended for much longer until an effective reorientation of consciousness occurs. Scientific researches and discussions are fundamental tools to the understanding of issues still little explored in this field.

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ABSTRACT OBJECTIVE This study aims to assess covid-19 morbidity, mortality, and severity from 2020 to 2021 in five Brazilian Amazon states with the highest records of wildfires. METHODS A distributed lag non-linear model was applied to estimate the potential exposure risk association with particulate matter smaller than 2.5-µm in diameter (PM2.5). Daily mean temperature, relative humidity, percentual of community mobility, number of hospital beds, days of the week, and holidays were considered in the final models for controlling the confounding factors. RESULTS The states of Para, Mato Grosso, and Amazonas have reported the highest values of overall cases, deaths, and severe cases of covid-19. The worrying growth in the percentual rates in 2020/2021 for the incidence, severity, and mortality were highlighted in Rondônia and Mato Grosso. The growth in 2020/2021 in the estimations of PM2.5 concentrations was higher in Mato Grosso, with an increase of 24.4%, followed by Rondônia (14.9%). CONCLUSION This study establishes an association between wildfire-generated PM2.5 and increasing covid-19 incidence, mortality, and severity within the studied area. The findings showed that the risk of covid-19 morbidity and mortality is nearly two times higher among individuals exposed to high concentrations of PM2.5. The attributable fraction to PM2.5 in the studied area represents an important role in the risk associated with covid-19 in the Brazilian Amazon region.

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Throughout the years, wildfires have negatively impacted ecological systems and urban areas. Hence, reinforcing territorial risk management strategies against wildfires is essential. In this study, we built an early alert system (EAS) with two different Machine Learning (ML) techniques to calculate the meteorological conditions of two Colombian areas: (i) A 3D convolutional neural net capable of learning from satellite data and (ii) a convolutional network to bias-correct the Weather Research and Forecasting (WRF) model output. The results were used to quantify the daily Fire Weather Index and were coupled with the outcomes from a land cover analysis conducted through a Naïve-Bayes classifier to estimate the probability of wildfire occurrence. These results, combined with an assessment of global vulnerability in both locations, allow the construction of daily risk maps in both areas. On the other hand, a set of short-term preventive and corrective measures were suggested to public authorities to implement, after an early alert prediction of a possible future wildfire. Finally, Soil Management Practices are proposed to tackle the medium- and long-term causes of wildfire development, with the aim of reducing vulnerability and promoting soil protection. In conclusion, this paper creates an EAS for wildfires, based on novel ML techniques and risk maps.

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Background: Terrestrial biomes in South America are likely to experience a persistent increase in environmental temperature, possibly combined with moisture reduction due to climate change. In addition, natural fire ignition sources, such as lightning, can become more frequent under climate change scenarios since favourable environmental conditions are likely to occur more often. In this sense, changes in the frequency and magnitude of natural fires can impose novel stressors on different ecosystems according to their adaptation to fires. By focusing on Brazilian biomes, we use an innovative combination of techniques to quantify fire persistence and occurrence patterns over time and evaluate climate risk by considering key fire-related climatic characteristics. Then, we tested four major hypotheses considering the overall characteristics of fire-dependent, fire-independent, and fire-sensitive biomes concerning (1) fire persistence over time; (2) the relationship between climate and fire occurrence; (3) future predictions of climate change and its potential impacts on fire occurrence; and (4) climate risk faced by biomes. Methods: We performed a Detrended Fluctuation Analysis to test whether fires in Brazilian biomes are persistent over time. We considered four bioclimatic variables whose links to fire frequency and intensity are well-established to assess the relationship between climate and fire occurrence by confronting these climate predictors with a fire occurrence dataset through correlative models. To assess climate risk, we calculated the climate hazard, sensitivity, resilience, and vulnerability of Brazilian biomes, and then we multiplied the Biomes' vulnerability index by the hazards. Results: Our results indicate a persistent behaviour of fires in all Brazilian biomes at almost the same rates, which could represent human-induced patterns of fire persistence. We also corroborated our second hypothesis by showing that most fire-dependent biomes presented high thermal suitability to fire, while the fire-independent biome presented intermediate suitability and fire-sensitive biomes are the least suitable for fire occurrence. The third hypothesis was partially corroborated since fire-dependent and independent biomes are likely to increase their thermal suitability to fire, while fire-sensitive biomes are likely to present stable-to-decreasing thermal suitability in the future. Finally, our fourth hypothesis was partially corroborated since most fire-dependent biomes presented low climate risk, while the fire-independent biome presented a high risk and the fire-sensitive biomes presented opposite trends. In summary, while the patterns of fire persistence and fire occurrence over time are more likely to be related to human-induced fires, key drivers of burned areas are likely to be intensified across Brazilian biomes in the future, potentially increasing the magnitude of the fires and harming the biomes' integrity.

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BACKGROUND: There is currently a scarcity of air pollution epidemiologic data from low- and middle-income countries (LMICs) due to the lack of air quality monitoring in these countries. Additionally, there is limited capacity to assess the health effects of wildfire smoke events in wildfire-prone regions like Brazil's Amazon Basin. Emerging low-cost air quality sensors may have the potential to address these gaps. OBJECTIVES: We investigated the potential of PurpleAir PM2.5 sensors for conducting air pollution epidemiologic research leveraging the United States Environmental Protection Agency's United States-wide correction formula for ambient PM2.5. METHODS: We obtained raw (uncorrected) PM2.5 concentration and humidity data from a PurpleAir sensor in Rio Branco, Brazil, between 2018 and 2019. Humidity measurements from the PurpleAir sensor were used to correct the PM2.5 concentrations. We established the relationship between ambient PM2.5 (corrected and uncorrected) and daily all-cause respiratory hospitalization in Rio Branco, Brazil, using generalized additive models (GAM) and distributed lag non-linear models (DLNM). We used linear regression to assess the relationship between daily PM2.5 concentrations and wildfire reports in Rio Branco during the wildfire seasons of 2018 and 2019. RESULTS: We observed increases in daily respiratory hospitalizations of 5.4% (95%CI: 0.8%, 10.1%) for a 2-day lag and 5.8% (1.5%, 10.2%) for 3-day lag, per 10 µg/m3 PM2.5 (corrected values). The effect estimates were attenuated when the uncorrected PM2.5 data was used. The number of reported wildfires explained 10% of daily PM2.5 concentrations during the wildfire season. DISCUSSION: Exposure-response relationships estimated using corrected low-cost air quality sensor data were comparable with relationships estimated using a validated air quality modeling approach. This suggests that correcting low-cost PM2.5 sensor data may mitigate bias attenuation in air pollution epidemiologic studies. Low-cost sensor PM2.5 data could also predict the air quality impacts of wildfires in Brazil's Amazon Basin.

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Forest fires alter soil microbial communities that are essential to support ecosystem recovery following land burning. These alterations have different responses according to soil abiotic pre- and post-fire conditions and fire severity, among others, and tend to decrease along vegetation recovery over time. Thus, understanding the effects of fires on microbial soil communities is critical to evaluate ecosystem resilience and restoration strategies in fire-prone ecosystems. We studied the state of community-level physiological profiles (CLPPs) and the prokaryotic community structure of rhizosphere and bulk soils from two fire-affected sclerophyll forests (one surveyed 17 months and the other 33 months after fire occurrence) in the Mediterranean climate zone of central Chile. Increases in catabolic activity (by average well color development of CLPPs), especially in the rhizosphere as compared with the bulk soil, were observed in the most recently affected site only. Legacy of land burning was still clearly shaping soil prokaryote community structure, as shown by quantitative PCR (qPCR) and Illumina MiSeq sequencing of the V4 region of the 16S rRNA gene, particularly in the most recent fire-affected site. The qPCR copy numbers and alpha diversity indexes (Shannon and Pielou's evenness) of sequencing data decreased in burned soils at both locations. Beta diversity analyses showed dissimilarity of prokaryote communities at both study sites according to fire occurrence, and NO3 - was the common variable explaining community changes for both of them. Acidobacteria and Rokubacteria phyla significantly decreased in burned soils at both locations, while Firmicutes and Actinobacteria increased. These findings provide a better understanding of the resilience of soil prokaryote communities and their physiological conditions in Mediterranean forests of central Chile following different time periods after fire, conditions that likely influence the ecological processes taking place during recovery of fire-affected ecosystems.

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Resilience is the ability of a system to absorb disturbances, rearrange itself, and adapt in order to maintain its functionality, structure, identity, and feedback. Research involving fire resilience in subtropical wetlands (SW) allows us to understand the dynamics of these ecosystems, measure impacts on fauna and flora, and promote policies for the management and protection. The aim of the present study is to assess the fire resilience of SW. The study was divided into three steps: (i) burned area classification, (ii) vegetation pattern classification, and (iii) temporal analysis of SW fire resilience based on NDVI calculation. Our results show that (a) high resilience potential of emerging plants, which developed green leaves in less than 90 days after the fire; (b) poor recovery of peatlands with underground fire history. Daily coverage of high spatial resolution PlanetScope images has great potential for classification and monitoring of land use in areas where there are rapid changes, such as after a fire event, explosions, and dam ruptures with ore tailings, for example.

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RESUMEN El humo de los incendios forestales puede influir en la mortalidad, las emergencias y las visitas ambulatorias, especialmente en personas con problemas respiratorios y cardiovasculares. La vigilancia intensificada exige sumar recursos adicionales a las actividades rutinarias de vigilancia. En agosto del 2019, se registraron 25.299 focos de incendios en varios departamentos del Paraguay. Se describen los hallazgos de la vigilancia intensificada de enfermedades en la población afectada por incendios forestales en Paraguay en el 2019. Se realizó un estudio descriptivo trasversal entre el 15/08/19 al 4/10/2019 en todo el territorio nacional. Como fuente de datos, se incluyen reportes de las Unidades Epidemiológicas Regionales, organizados en una base de datos con las variables: departamento, distrito, población indígena, número de atenciones médicas, motivo de consulta, heridos graves, desaparecidos y fallecidos, identificación de riesgos potenciales para la salud. Fueron afectados 12 (12/17) departamentos y la Capital del país, 30 distritos y 12 comunidades indígenas. Se realizaron 1.681 atenciones médicas, de los cuales 1.291 (77%) eran de Alto Paraguay. Las enfermedades más frecuentes fueron Infecciones Respiratorias Agudas no neumonías (36%), y Enfermedades Tipo Influenza (18%). No se registraron heridos graves, personas desaparecidas ni fallecidas. Como riesgos potenciales para la salud: pérdidas de viviendas en comunidades indígenas, cultivos, ganados y la interrupción de provisión de agua. En conclusión, los cuadros respiratorios fueron más frecuentes durante los incendios forestales, no se registraron personas desaparecidas ni fallecidas. Se identificaron riesgos potenciales para la salud por afectación de medios de vida y sustento, sobre todo en poblaciones indígenas.

ABSTRACT Smoke from wildfires can influence mortality, emergencies and outpatient visits, especially in people with respiratory and cardiovascular problems. Intensified surveillance requires adding up additional resources to routine surveillance activities. In August 2019, 25,299 fire outbreaks were registered in de various departments Paraguay. The findings of the intensified surveillance of diseases in the population affected by wildfires in Paraguay in 2019 are described. A descriptive cross-sectional study was carried out between 08/15/19 to 10/4/2019 throughout the national territory. As a data source, reports from the Regional Epidemiological Units, organized in a database with the variables: department, district, indigenous populations, number of medical care, reason for consultation, seriously injured, missing and deceased people, identification of potential health risks. Twelve (12/17) departments and the capital of the country, 30 districts and 12 indigenous peoples were affected. One thousand six hundred and eighty-one medical services were performed, of which 1,291 (77%) were from Alto Paraguay. The most frequent diseases were non-pneumonia Acute Respiratory Infections (36%), and Influenza-like illness (18%). There were no injured, missing or dead people. Among the potential health risks: loss of dwellings in indigenous people, crops, livestock and the interruption of water supply. In conclusion, respiratory symptoms were the most frequent during the wildfires, there were no injured, missing or dead people. Potential health risks were identified due to the impact on livelihoods, especially in indigenous populations.

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The spatial and temporal behavior of the occurrence of forest fires in Chile was evaluated in the presence of COVID-19 and mobility restrictions. The fire period from 2015-2016 to 2020-2021 was considered and statistics on mobility restrictions were granted by the Government of Chile. The analysis was developed at different scales of geographic perception. At the national and regional levels, the global behavior of the occurrence was determined, and later at the communal level, the political territorial unit, to determine internal variations attributable to the mobility dynamics in the quarantine period. In the process, the meteorological background of the fire activity was also considered. The results indicate that it is possible to rule out a meteorological effect, based on the variation of the moisture content of fine fuel. There was also no statistical association between the humidity of the fuel and the variation in the occurrence of fires. It is concluded that the communes that presented the greatest mobility of people before the pandemic were those that obtained the greatest reduction in fires. The variation in mobility, the product of restriction measures, is a statistical predictor of the increase or decrease in fires.

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Fires can pose a threat to forest ecosystems when those ecosystems are not fire-adapted or when forest community conditions make them vulnerable to wildfires. Thus, investigating fire-prone environmental conditions is urgently needed to create action plans that preserve these ecosystems. In this sense, climate variables can determine the environmental conditions favorable for forest fires. Our study confirms that vapor pressure deficit (VPD) is an essential climate indicator for forest fires, as it is related to maximum temperatures and low humidity, representing the stress conditions for vegetation prone to fires. This study explores the extent to which ENSO phases can modulate climatic conditions that lead to high VPD over Guanajuato, a semi-arid region in central Mexico, during the dry season (March-April-May). Using fire occurrence data from MODIS (2000-2019) and Landsat 5 (1998-1999), we developed a climatic probability model for the occurrence of forest fires using VPD estimated from ERA5 reanalysis for each ENSO phase. We found that VPD and the occurrence of forest fires were higher during El Niño than under Neutral and La Niña years, with a higher risk of forest fire occurrence in Guanajuato's southern region. This study concludes that it is necessary to implement regional and local fire management plans, especially where the largest number of natural protected areas is located.

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In the Brazilian Pantanal, wildfire occurrence has increased, reaching record highs of over 40,000 km2 in 2020. Smoke from wildfires worsened the situation of isolated, as well as urban communities, already under an increasing toll of COVID-19. Here we review the impacts and the possible causes of the 2020 mega-fires and recommend improvements for public policies and fire management in this wetland. We calculated the amount of area burnt annually since 2003 and describe patterns in precipitation and water level measurements of the Paraguay River. Our analyses revealed that the 2020 wildfires were historically unprecedented, as 43% of the area (over 17,200 km2) had not been burnt previously in the last two decades. The extent of area affected in 2020 represents a 376% increase compared to the annual average of the area burnt annually in the last two decades, double than the value in 2019. Potential factors responsible for this increase are (i) severe drought decreased water levels, (ii) the fire corridor was located in the Paraguay River flood zone, (iii) constraints on firefighters, (iv) insufficient fire prevention strategy and agency budget reductions, and (v) recent landscape changes. Climate and land use change will further increase the frequency of these extreme events. To make fire management more efficient and cost-effective, we recommend the implementation of an Integrated Fire Management program in the Pantanal. Stakeholders should use existing traditional, local ecological, and scientific knowledge to form a collective strategy with clear, achievable, measurable goals, considering the socio-ecological context. Permanent fire brigades, including indigenous members, should conduct year-round fire management. Communities should cooperate to create a collaborative network for wildfire prevention, the location and characteristics (including flammability) of infrastructures should be (re)planned in fire-prone environments considering and managing fire-catalysed transitions, and depending on the severity of wildfires. The 2020 wildfires were tackled in an ad-hoc fashion and prioritisation of areas for urgent financial investment, management, protection, and restoration is necessary to prevent this catastrophe from happening again.

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The 2019-2020 summer wildfire event on the east coast of Australia was a series of major wildfires occurring from November 2019 to end of January 2020 across the states of Queensland, New South Wales (NSW), Victoria and South Australia. The wildfires were unprecedent in scope and the extensive character of the wildfires caused smoke pollutants to be transported not only to New Zealand, but also across the Pacific Ocean to South America. At the peak of the wildfires, smoke plumes were injected into the stratosphere at a height of up to 25 km and hence transported across the globe. The meteorological and air quality Weather Research and Forecasting with Chemistry (WRF-Chem) model is used together with the air quality monitoring data collected during the bushfire period and remote sensing data from the Moderate Resolution Imaging Spectroradiometer (MODIS) and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellites to determine the extent of the wildfires, the pollutant transport and their impacts on air quality and health of the exposed population in NSW. The results showed that the WRF-Chem model using Fire Emission Inventory (FINN) from National Center for Atmospheric Research (NCAR) to simulate the dispersion and transport of pollutants from wildfires predicted the daily concentration of PM2.5 having the correlation (R2) and index of agreement (IOA) from 0.6 to 0.75 and 0.61 to 0.86, respectively, when compared with the ground-based data. The impact on health endpoints such as mortality and respiratory and cardiovascular diseases hospitalizations across the modelling domain was then estimated. The estimated health impact on each of the Australian Bureau of Statistics (ABS) census districts (SA4) of New South Wales was calculated based on epidemiological assumptions of the impact function and incidence rate data from the 2016 ABS and NSW Department of Health statistical health records. Summing up all SA4 census district results over NSW, we estimated that there were 247 (CI: 89, 409) premature deaths, 437 (CI: 81, 984) cardiovascular diseases hospitalizations and 1535 (CI: 493, 2087) respiratory diseases hospitalizations in NSW over the period from 1 November 2019 to 8 January 2020. The results are comparable with a previous study based only on observation data, but the results in this study provide much more spatially and temporally detailed data with regard to the health impact from the summer 2019-2020 wildfires.

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Severe biomass burning (BB) events have become increasingly common in South America in the last few years, mainly due to the high number of wildfires observed recently. Such incidents can negatively influence the air quality index associated with PM2.5 (particulate matter, which is harmful to human health). A study performed in the Metropolitan Area of São Paulo (MASP) took place on selected days of July 2019, evaluated the influence of a BB event on air quality. Use of combined remote sensing, a surface monitoring system and data modeling and enabled detection of the BB plume arrival (light detection and ranging (lidar) ratio of (50 ± 34) sr at 532 nm, and (72 ± 45) sr at 355 nm) and how it affected the Ångström exponent (>1.3), atmospheric optical depth (>0.7), PM2.5 concentrations (>25 µg.m-3), and air quality classification. The utilization of high-order statistical moments, obtained from elastic lidar, provided a new way to observe the entrainment process, allowing understanding of how a decoupled aerosol layer influences the local urban area. This new novel approach enables a lidar system to obtain the same results as a more complex set of instruments and verify how BB events contribute from air masses aloft towards near ground ones.

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La exposición a las emanaciones de incendios forestales es un importante problema de salud pública nacional e internacional. El cambio climático que conlleva sequía y aumento de la temperatura estival aumenta el riesgo y magnitud de los episodios de incendios forestales, generándose grandes incendios cuyas emanaciones pueden afectar a poblaciones distanciadas del epicentro. La asociación entre la exposición a las emanaciones de los incendios forestales, el aumento de las concentraciones de material particulado aéreo y la morbilidad respiratoria (exacerbación de asma y enfermedades respiratorias crónicas) ha sido evidenciada en diversos estudios. Sin embargo, es difícil realizar un metaanálisis de ellos, ya que la metodología empleada es muy disímil. Entre los principales mecanismos de morbilidad se encontrarían: la producción de citoquinas proinflamatorias, la activación endotelial y la disfunción del sistema nervioso autónomo. Ante la exposición al humo de incendios forestales, se produce daño tisular, aumento de los mecanismos protrombóticos, aumento de la presión arterial y cambios en el ritmo cardiaco, que explicaría los efectos cardiovasculares. Los sujetos con patología cardiovascular preexistente podrían tener mayor riesgo cardiovascular; sin embargo, existen factores confundentes en esta asociación. Por otra parte, el posible riesgo cancerígeno con la exposición a estas emanaciones requiere mayores estudios poblacionales.

Exposure to forest fire fumes is a major national and international public health issue. Climate change that leads to drought and increased summer temperature increases the risk and magnitude of wildfires episodes, generating mega-fires whose fumes not only affect the boundary population, but they may become transcontinental. Association between exposure to forest fire fumes, mainly increased concentrations of air born particulate matter and respiratory morbidity (exacerbation of asthma and chronic respiratory diseases) has been evidenced by diverse studies. However, it is difficult to carry out meta-analysis with them since the methodology used is dissimilar. Among the main causes of morbidity have been postulated the production of pro-inflammatory cytokines, endothelial activation and dysfunction of the autonomic nervous system. Occurrence of tissue damage, increased prothrombotic mechanisms, increased blood pressure and changes in heart rate, would explain the cardiovascular effects associated with exposure to smoke from these fires. However, epidemiological outcomes have not been entirely consistent, as the association between cardiovascular morbidity and exposure to wildfire fumes may be mixed with confounding factors. Despite this, patients with pre-existing cardiovascular pathology may be at increased risk. Finally, the potential risk of carcinogen with exposure to these fumes requires further population studies.

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