An investigation of the impact of Canadian wildfires on US air quality using model, satellite, and ground measurements

<p>Canadian wildfires transport large concentrations of particulate matter into the US, leading to various effects on the surface temperature, the radiation balance, and visibility and exacerbating pollution-related respiratory conditions. Using a combination of surface, satellite, and numeric...

Full description

Saved in:
Bibliographic Details
Main Authors: Z. Xue, N. Udaysankar, S. A. Christopher
Format: Article
Language:English
Published: Copernicus Publications 2025-06-01
Series:Atmospheric Chemistry and Physics
Online Access:https://acp.copernicus.org/articles/25/5497/2025/acp-25-5497-2025.pdf
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850232776610021376
author Z. Xue
Z. Xue
N. Udaysankar
S. A. Christopher
author_facet Z. Xue
Z. Xue
N. Udaysankar
S. A. Christopher
author_sort Z. Xue
collection DOAJ
description <p>Canadian wildfires transport large concentrations of particulate matter into the US, leading to various effects on the surface temperature, the radiation balance, and visibility and exacerbating pollution-related respiratory conditions. Using a combination of surface, satellite, and numerical models, this study quantifies the increase in surface fine particulate matter (<span class="inline-formula">PM<sub>2.5</sub></span>) in the continental US due to long-range transported smoke from Canadian wildfires during a wildfire episode from 9–25 August 2018. As a widely used indicator of surface pollution levels, satellite-retrieved aerosol optical depth (AOD) can provide crucial information on columnar pollution mass. However, the daily spatial coverage of satellite AOD is restricted due to cloud cover. In order to quantify the daily changes in surface pollution, we fill in the AOD gaps by utilizing simulated 10 <span class="inline-formula">km</span> spatial resolution AOD from a chemistry transport model (CTM). Meteorological variables influencing smoke transport were also integrated alongside the gap-filled AOD product to estimate surface <span class="inline-formula">PM<sub>2.5</sub></span> using geographically weighted regression (GWR) and random forest (RF) models. The model with better performance was subsequently applied to quantify <span class="inline-formula">PM<sub>2.5</sub></span> changes due to Canadian wildfires. To isolate the impact of Canadian wildfires, we calculate the surface <span class="inline-formula">PM<sub>2.5</sub></span> ratio with and without Canadian fire sources by conducting two CTM simulations: one with Canadian wildfire emissions enabled and another with these emissions turned off. Our results show that Canadian wildfires caused a significant increase in surface <span class="inline-formula">PM<sub>2.5</sub></span>, contributing up to 28 <span class="inline-formula">µg m<sup>−3</sup></span> (a 69 <span class="inline-formula">%</span> increase) across different US Environmental Protection Agency (EPA) regions during the August 2018 wildfire event.</p>
format Article
id doaj-art-4adbdc5706d3482abe34da0586c83989
institution OA Journals
issn 1680-7316
1680-7324
language English
publishDate 2025-06-01
publisher Copernicus Publications
record_format Article
series Atmospheric Chemistry and Physics
spelling doaj-art-4adbdc5706d3482abe34da0586c839892025-08-20T02:03:05ZengCopernicus PublicationsAtmospheric Chemistry and Physics1680-73161680-73242025-06-01255497551710.5194/acp-25-5497-2025An investigation of the impact of Canadian wildfires on US air quality using model, satellite, and ground measurementsZ. Xue0Z. Xue1N. Udaysankar2S. A. Christopher3Department of Atmospheric and Earth Science, University of Alabama in Huntsville, Huntsville, AL, USAnow at: Department of Chemical and Biochemical Engineering, The University of Iowa, Iowa City, IA, USA​​​​​​​Department of Atmospheric and Earth Science, University of Alabama in Huntsville, Huntsville, AL, USADepartment of Atmospheric and Earth Science, University of Alabama in Huntsville, Huntsville, AL, USA<p>Canadian wildfires transport large concentrations of particulate matter into the US, leading to various effects on the surface temperature, the radiation balance, and visibility and exacerbating pollution-related respiratory conditions. Using a combination of surface, satellite, and numerical models, this study quantifies the increase in surface fine particulate matter (<span class="inline-formula">PM<sub>2.5</sub></span>) in the continental US due to long-range transported smoke from Canadian wildfires during a wildfire episode from 9–25 August 2018. As a widely used indicator of surface pollution levels, satellite-retrieved aerosol optical depth (AOD) can provide crucial information on columnar pollution mass. However, the daily spatial coverage of satellite AOD is restricted due to cloud cover. In order to quantify the daily changes in surface pollution, we fill in the AOD gaps by utilizing simulated 10 <span class="inline-formula">km</span> spatial resolution AOD from a chemistry transport model (CTM). Meteorological variables influencing smoke transport were also integrated alongside the gap-filled AOD product to estimate surface <span class="inline-formula">PM<sub>2.5</sub></span> using geographically weighted regression (GWR) and random forest (RF) models. The model with better performance was subsequently applied to quantify <span class="inline-formula">PM<sub>2.5</sub></span> changes due to Canadian wildfires. To isolate the impact of Canadian wildfires, we calculate the surface <span class="inline-formula">PM<sub>2.5</sub></span> ratio with and without Canadian fire sources by conducting two CTM simulations: one with Canadian wildfire emissions enabled and another with these emissions turned off. Our results show that Canadian wildfires caused a significant increase in surface <span class="inline-formula">PM<sub>2.5</sub></span>, contributing up to 28 <span class="inline-formula">µg m<sup>−3</sup></span> (a 69 <span class="inline-formula">%</span> increase) across different US Environmental Protection Agency (EPA) regions during the August 2018 wildfire event.</p>https://acp.copernicus.org/articles/25/5497/2025/acp-25-5497-2025.pdf
spellingShingle Z. Xue
Z. Xue
N. Udaysankar
S. A. Christopher
An investigation of the impact of Canadian wildfires on US air quality using model, satellite, and ground measurements
Atmospheric Chemistry and Physics
title An investigation of the impact of Canadian wildfires on US air quality using model, satellite, and ground measurements
title_full An investigation of the impact of Canadian wildfires on US air quality using model, satellite, and ground measurements
title_fullStr An investigation of the impact of Canadian wildfires on US air quality using model, satellite, and ground measurements
title_full_unstemmed An investigation of the impact of Canadian wildfires on US air quality using model, satellite, and ground measurements
title_short An investigation of the impact of Canadian wildfires on US air quality using model, satellite, and ground measurements
title_sort investigation of the impact of canadian wildfires on us air quality using model satellite and ground measurements
url https://acp.copernicus.org/articles/25/5497/2025/acp-25-5497-2025.pdf
work_keys_str_mv AT zxue aninvestigationoftheimpactofcanadianwildfiresonusairqualityusingmodelsatelliteandgroundmeasurements
AT zxue aninvestigationoftheimpactofcanadianwildfiresonusairqualityusingmodelsatelliteandgroundmeasurements
AT nudaysankar aninvestigationoftheimpactofcanadianwildfiresonusairqualityusingmodelsatelliteandgroundmeasurements
AT sachristopher aninvestigationoftheimpactofcanadianwildfiresonusairqualityusingmodelsatelliteandgroundmeasurements
AT zxue investigationoftheimpactofcanadianwildfiresonusairqualityusingmodelsatelliteandgroundmeasurements
AT zxue investigationoftheimpactofcanadianwildfiresonusairqualityusingmodelsatelliteandgroundmeasurements
AT nudaysankar investigationoftheimpactofcanadianwildfiresonusairqualityusingmodelsatelliteandgroundmeasurements
AT sachristopher investigationoftheimpactofcanadianwildfiresonusairqualityusingmodelsatelliteandgroundmeasurements