Impacts of prescribed fires and benefits from their reduction for air quality, health, and visibility in the Pacific Northwest of the United States

Abstract

Using a WRF-SMOKE-CMAQ modeling framework, we investigate the impacts of smoke from prescribed fires on model performance, regional and loc al air quality, health impacts, and visibility in protected natural environments using three different prescribed fire emission scenarios: 100% fire, no fire, and 30% fire. The 30% fire case reflects a 70% reduction in fire activities due to harvesting of logging residues for use as a feedstock for a potential aviation biofuel supply chain. Overall model performance improves for several performance metrics when fire emissions are included, especially for organic carbon, irrespective of the model goals and criteria used. This effect on model performance is more pronounced for the rural and remote IMPROVE sites for organic carbon and total PM 2.5 . A reduction in prescribed fire emissions (30% fire case) results in significant improvement in air quality in areas in western Oregon, northern Idaho, and western Montana, where most prescribed fires occur. Prescribed burning contributes to visibility impairment, and a relatively large portion of protected class I areas will benefit from a reduced emission scenario. For the haziest 20% days, prescribed burning is an important source of visibility impairment, and approximately 50% of IMPROVE sites in the model domain show a significant improvement in visibility for the reduced fire case. Using BenMAP, a health impact assessment tool, we show that several hundred additional deaths, several thousand upper and lower respiratory symptom cases, several hundred bronchitis cases, and more than 35,000 workday losses can be attributed to prescribed fires, and these health impacts decrease by 25-30% when a 30% fire emission scenario is considered.Implications: This study assesses the potential regional and local air quality, public health, and visibility impacts from prescribed burning activities, as well as benefits that can be achieved by a potential reduction in emissions for a scenario where biomass is harvested for conversion to biofuel. As prescribed burning activities become more frequent, they can be more detrimental for air quality and health. Forest residue-based biofuel industry can be source of cleaner fuel with cobenefits of improved air quality, reduction in health impacts, and improved visibility.

Causes of Big Bushfires in Australia: Higher Temperatures and Rainfall or More Fuel?

“…One of the chief effects of bushfires is that of smoke inhalation (Johnston et al, 2002;Yu et al, 2020). The same concerns relate to prescribed burning (Ravi et al, 2019). The present study has not included the smaller bushfires, some of which like the Black Friday 2009 event caused losses estimated at 11.8 bn AU$ (Ladds et al, 2017).…”

Integration of a Coupled Fire-Atmosphere Model Into a Regional Air Quality Forecasting System for Wildfire Events

“…However, in 2020, AIRPACT was updated with the Fire Information System with BlueSky Pipeline. The evolution of the operational AIRPACT forecast methodology is documented in the following papers (Vaughan et al, 2004;Chen et al, 2008;Herron-Thorpe et al, 2014;Ravi et al, 2018Ravi et al, , 2019 and at http://www.lar.wsu.edu/airpact.…”

The Los Angeles 100% Renewable Energy Study (LA100): Chapter 9. Air Quality and Public Health

“…Gridded outputs from photochemical models such as WRF-Chem have been used in a number of studies for estimating the burden of disease from air pollution at various scales (regional, national, or global) as well as from various sectors (e.g., transportation, electric generation, wildland fires) Ford et al, 2018;Ravi et al, 2018Ravi et al, , 2019Anenberg et al, 2019). For the change in pollutant exposure (∆C) required by the health impact function, we calculate the gridded differences in concentration of O3 and PM2.5 from different combination of LA100 scenarios to gain insight into the effects of isolating power sector emissions and load levels.…”