Samaneh Ashraf, Francesco S R Pausata, Sylvie Leroyer, Robin Stevens, Rodrigo Munoz-Alpizar
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引用次数: 0
Abstract
Extensive lockdowns during the COVID-19 pandemic caused a remarkable decline in human activities that have influenced urban climate, especially air quality and urban heat islands. However, the impact of such changes on local climate based on long term ground-level observations has hitherto not been investigated. Using air pollution measurements for the four major Canadian metropolitan areas (Toronto, Montreal, Vancouver, and Calgary), we find that PM2.5 markedly decreased during and after lockdowns with peak reduction ranging between 42% and 53% relative to the 2000-2019 reference period. Moreover, we show a substantial decline in canopy urban heat island intensity during lockdown and in the post lockdowns periods with peak reduction ranging between 0.7°C and 1.6°C in comparison with the 20-year preceding period. The results of this study may provide insights for local policymakers to define the regulation strategies to facilitate air quality improvement in urban areas.
期刊介绍:
GeoHealth will publish original research, reviews, policy discussions, and commentaries that cover the growing science on the interface among the Earth, atmospheric, oceans and environmental sciences, ecology, and the agricultural and health sciences. The journal will cover a wide variety of global and local issues including the impacts of climate change on human, agricultural, and ecosystem health, air and water pollution, environmental persistence of herbicides and pesticides, radiation and health, geomedicine, and the health effects of disasters. Many of these topics and others are of critical importance in the developing world and all require bringing together leading research across multiple disciplines.