In order to study the impact of heat waves on ozone in southern Canada, this paper analyzes the ground-level and tropospheric ozone pollution in the heat wave impact and non-impact periods in this region, and uses multivariate data and BenMAP-CE software to compare the correlation between ground-level ozone and temperature, ozone and relative humidity, and their impacts on human health during the impact and non-impact periods of the heat wave in the southern region of Canada. The study shows that: (1) the overall spatial distribution patterns of tropospheric ozone and ground-level ozone concentrations in southern Canada are high in the southeast and low in the northwest, and the ozone concentrations are significantly higher during the heatwave-affected period than during the non-heatwave-affected period. (2) Temperature-ozone correlations were mainly uncorrelated in the eastern and western parts of the study region during non-heatwave-affected periods. The occurrence of summer heat waves enhanced the positive temperature-ozone correlation in most areas. (3) The negative correlation between relative humidity and ozone in the study area during the heatwave-affected period accounted for a smaller percentage of the area than in the non-affected period. The presence of heat waves weakened the negative correlation between relative humidity and ozone. (4) The occurrence of heat waves in the study area led to an increase in the number of deaths due to ozone exposure, with growth rates ranging from 22.6% to 23.2%, and there were significant gender and geographic differences in the number of deaths due to ozone exposure. It was concluded that ozone pollution in the region is closely related to the occurrence of heat waves, and that the strengthening of integrated research on air pollution and climate change will be a major task for the future. 

Kai Zhang, Guofeng Dang. Impact of Heatwave Events on Ozone Pollution and Its Health Effects in Southern Canada. Academic Journal of Environment & Earth Science(2025), Vol. 7, Issue 2: 7-20. https://doi.org/10.25236/AJEE.2025.070202.

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