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Wildfires are a significant threat to human health, in part through degraded air quality. Prescribed burning can reduce wildfire severity but can also lead to an increase in air pollution. The complexities of fires and atmospheric processes lead to uncertainties when predicting the air quality impacts of fire and make it difficult to fully assess the costs and benefits of an expansion of prescribed fire. By modeling differences in emissions, surface conditions, and meteorology between wildfire and prescribed burns, we present a novel comparison of the air quality impacts of these fire types under specific scenarios. One wildfire and two prescribed burn scenarios were considered, with one prescribed burn scenario optimized for potential smoke exposure. We found that PM2.5 emissions were reduced by 52%, from 0.27 to 0.14 Tg, when fires burned under prescribed burn conditions, considerably reducing PM2.5 concentrations. Excess short-term mortality from PM2.5 exposure was 40 deaths for fires under wildfire conditions and 39 and 15 deaths for fires under the default and optimized prescribed burn scenarios, respectively. Our findings suggest prescribed burns, particularly when planned during conditions that minimize smoke exposure, could be a net benefit for the impacts of wildfires on air quality and health.

This updated meta-synthesis explores further dimensions of the lived experience of severe and enduring anorexia nervosa (SE-AN) since recent contention regarding proposed “terminal anorexia nervosa (T-AN)”. The paper aims to update the original synthesis and to situate participant responses to the category of “T-AN”. Thus, extending the proposed conceptualization of the SE-AN experience. A systematic search identified published scholarship (between August 2022 and July 2023), derived from five bibliographic databases. A comprehensive methodology combining Interpretative Phenomenological Analysis and a meta-ethnographic framework enabled the synthesis of meta-themes across 9 new studies. These meta-themes were mapped onto the primary synthesis to further develop upon the earlier LE conceptualization of SE-AN. Nine extracted papers expanded the voices to 447 people within 45 studies. All papers affirmed and enriched the previous themes, and a novel theme was generated from the recent papers. The new theme, “walking on a knife’s edge, caught between worlds“, informed an expanded conceptualization of SE-AN, termed the Web of Hope. Thus, demonstrating how participants held onto hope in the face of the SE-AN experience. Death, dying and “terminality”, were notably absent in the 36 papers in the previous meta-synthesis. Since the proposal of the category of “terminal anorexia” in 2022, studies on the lived experience of SE-AN increasingly focused on how people hold onto hope alongside SE-AN. The findings further drive the field to reflect on therapeutic interventions, labelling and diagnosis, in the face of unknowns, on the premise of “first, do no harm”. [ABSTRACT FROM AUTHOR]

The Australian 2019/2020 bushfires were unprecedented in their extent and intensity, causing a catastrophic loss of habitat, human and animal life across eastern‐Australia. We use a regional air quality model to assess the impact of the bushfires on particulate matter with a diameter less than 2.5 μm (PM2.5) concentrations and the associated health impact from short‐term population exposure to bushfire PM2.5. The mean population Air Quality Index (AQI) exposure between September and February in the fires and no fires simulations indicates an additional ∼437,000 people were exposed to "Poor" or worse AQI levels due to the fires. The AQ impact was concentrated in the cities of Sydney, Newcastle‐Maitland, Canberra‐Queanbeyan and Melbourne. Between October and February 171 (95% CI: 66–291) deaths were brought forward due to short‐term exposure to bushfire PM2.5. The health burden was largest in New South Wales (NSW) (109 (95% CI: 41–176) deaths brought forward), Queensland (15 (95% CI: 5–24)), and Victoria (35 (95% CI: 13–56)). This represents 38%, 13% and 30% of the total deaths brought forward by short‐term exposure to all PM2.5. At a city‐level 65 (95% CI: 24–105), 23 (95% CI: 9–38) and 9 (95% CI: 4–14) deaths were brought forward from short‐term exposure to bushfire PM2.5, accounting for 36%, 20%, and 64% of the total deaths brought forward from all PM2.5. Thus, the bushfires caused substantial AQ and health impacts across eastern‐Australia. Climate change is projected to increase bushfire risk, therefore future fire management policies should consider this. Plain Language Summary: The Australian 2019/2020 bushfires were unprecedented in their size and intensity, resulting in a catastrophic loss of habitat and human and animal life across eastern‐Australia. We use an air pollution model (WRF‐Chem) to quantify the impact of the bushfires on particulate matter with a diameter less than 2.5 μm (PM2.5) concentrations. We run the model with and without emissions from the fires so their impact on PM2.5 can be isolated. We find that between September and February an additional ∼437,000 people were exposed to "Poor" or worse air quality index levels due to the fires across eastern‐Australia. Short‐term exposure to high PM2.5 concentrations has been linked to negative health impacts. Therefore, we estimate the health impact of population exposure to bushfire PM2.5 across eastern‐Australia, regionally and at city level. Our estimate indicates that between October and February 171 deaths were brought forward due to exposure to PM2.5 from the fires. Regionally, most deaths were brought forward in New South Wales (109 deaths brought forward), Queensland (15), and Victoria (35). Within these regions, the most deaths were brought forward in Sydney (65), Melbourne (23), and Canberra‐Queanbeyan (9) as large populations were exposed to high PM2.5 concentrations due to the bushfires. Key Points: The fires led to widespread exposure to "Poor" or worse Air Quality Index levels across eastern‐AustraliaThe highest all‐cause, all‐age mortality from short‐term exposure to bushfire particulate matter with a diameter less than 2.5 μm (PM2.5) was seen in the states of New South Wales, Queensland, and VictoriaAll‐cause, all‐age mortality from short‐term exposure to bushfire PM2.5 was highest in the cities of Sydney, Melbourne, and Canberra [ABSTRACT FROM AUTHOR]

Indonesia contains large areas of peatland that have been drained and cleared of natural vegetation, making them susceptible to burning. Peat fires emit considerable amounts of carbon dioxide, particulate matter (PM) and other trace gases, contributing to climate change and causing regional air pollution. However, emissions from peat fires are uncertain, due to uncertainties in emission factors and fuel consumption. We used the Weather Research and Forecasting model with chemistry and measurements of PM concentrations to constrain PM emissions from Indonesian fires during 2015, one of the largest fire seasons in recent decades. We estimate primary PM 2.5 (particles with diameters less than 2.5 µ m) emissions from fires across Sumatra and Borneo during September–October 2015 were 7.33 Tg, a factor 3.5 greater than those in the Fire Inventory from NCAR (FINNv1.5), which does not include peat burning. We estimate similar dry fuel consumption and CO2 emissions to those in the Global Fire Emissions Database (GFED4s, including small fires) but PM 2.5 emissions that are a factor of 1.8 greater, due to updated PM 2.5 emission factors for Indonesian peat. Fires were responsible for an additional 3.12 Tg of secondary organic aerosol formation. Through comparing simulated and measured PM concentrations, our work provides independent support of these updated emission factors. We estimate peat burning contributed 71 % of total primary PM 2.5 emissions from fires in Indonesia during September–October 2015. We show that using satellite-retrieved soil moisture to modify the assumed depth of peat burn improves the simulation of PM, increasing the correlation between simulated and observed PM from 0.48 to 0.56. Overall, our work suggests that peat fires in Indonesia produce substantially greater PM emissions than estimated in current emission inventories, with implications for the predicted air quality impacts of peat burning. [ABSTRACT FROM AUTHOR]

Indonesia contains large areas of peatland which are being drained and cleared of natural vegetation, making them susceptible to burning. Peat fires emit considerable amounts of carbon dioxide, particulate matter (PM) and other trace gases, contributing to climate change and causing regional air pollution. However emissions from peat fires are uncertain due to uncertainties in emission factors and burn depth of peat. We used the Weather Research and Forecasting model with chemistry, and measurements of PM concentrations to constrain PM emissions from Indonesian fires during 2015, one of the largest fire seasons in recent decades. We estimate PM2.5 (particles with diameters less than 2.5μm) emissions from fires across Sumatra and Borneo during September to October 2015 were 7.33Tg, a factor 3.5 greater than those in Fire Inventory from NCAR (FINNv1.5), which does not include peat burning. We estimate similar dry fuel consumption and CO2 emissions to those in the Global Fire Emissions Database (GFED4s), but a factor 1.8 greater PM2.5 emissions, due to updated PM2.5 emission factors for Indonesian peat. Through comparing simulated and measured PM concentrations, our work provides an independent confirmation of these updated emission factors. We estimate peat burning contributes 71% of total PM2.5 emissions from fire in Indonesia during September-October 2015. We show that using satellite-retrieved soil moisture to modify the assumed depth of peat burn improves the simulation of PM, increasing the correlation between simulated and observed PM from 0.48 to 0.56. Overall, our work suggests that peat fires in Indonesia produce substantially greater PM emissions than estimated in current emission datasets, with implications for the predicted air quality impacts of peat burning. [ABSTRACT FROM AUTHOR]

Wildfires are a significant threat to human health, in part through degraded air quality. Prescribed burning can reduce wildfire severity but can also lead to an increase in air pollution. The complexities of fires and atmospheric processes lead to uncertainties when predicting the air quality impacts of fire and make it difficult to fully assess the costs and benefits of an expansion of prescribed fire. By modeling differences in emissions, surface conditions, and meteorology between wildfire and prescribed burns, we present a novel comparison of the air quality impacts of these fire types under specific scenarios. One wildfire and two prescribed burn scenarios were considered, with one prescribed burn scenario optimized for potential smoke exposure. We found that PM 2.5 emissions were reduced by 52%, from 0.27 to 0.14 Tg, when fires burned under prescribed burn conditions, considerably reducing PM 2.5 concentrations. Excess short-term mortality from PM 2.5 exposure was 40 deaths for fires under wildfire conditions and 39 and 15 deaths for fires under the default and optimized prescribed burn scenarios, respectively. Our findings suggest prescribed burns, particularly when planned during conditions that minimize smoke exposure, could be a net benefit for the impacts of wildfires on air quality and health.