Fire-Pollutant-Atmosphere Interaction and Its Impact on Mortality in
Portugal During Wildfire Seasons
Abstract
Wildfires expose populations to increased morbidity and mortality due to
the increase of air pollutant emissions. This study assesses the impact
of wildfire exposure in Portugal. In this work, we analyze the effects
of the wildfire seasons (June-July-August-September-October) on monthly
mortality by using data from atmospheric composition reanalysis, air
quality stations, remote sensing, and mortality for exposure assessment,
cluster analyses and regression models. Cluster analysis separated the
months within fire seasons with extreme atmospheric conditions (months
with more frequency of lower relative humidity and higher temperature,
higher pollutant concentrations and higher wildfire activities), Cluster
1, from months with cleaner air and stable atmospheric conditions,
Cluster 2. Linear regression showed statistically significant
(p-value < 0.05) correlation (r) between Cluster 1 and
cardiorespiratory mortalities due to Diseases of the Respiratory System
(DRS), Pneumonia (PNEU), Chronic Obstructive Pulmonary Disease (COPD)
and Diseases of the Circulatory System (DCS) (rDRS =
0.49; rPNEU = 0.42; rCOPD = 0.44;
rDCS = 0.45). Cluster 2 presented no significant
statistical correlation between atmospheric conditions and health
outcomes. Results shows epidemiological evidence that heat stress
combined with air pollution during wildfire season are contributing to
increase disease burden. Besides that, we performed smoke forecasts over
Portugal by using the Hybrid Single-Particle Lagrangian Integrated
Trajectory (HYSPLIT) model with satellite‐based fire emission. Forecasted
PM10 and PM2.5 concentration reproduced the behavior of the observations
(NRMSEPM10 = 3.70, rPM10 = 0.75;
NRMSEPM2.5 = 1.51, rPM2.5 = 0.46) during
October 15-16th, 2017, fire episode. BC results
matches with satellite observations.