6533b830fe1ef96bd129669b
RESEARCH PRODUCT
From COVID-19 to future electrification: Assessing traffic impacts on air quality by a machine-learning model
Stanley P. SanderYe WuJiming HaoElyse A. PenningtonYuk L. YungZhou WangShaojun ZhangJohn H. SeinfeldJiani YangJonathan H. JiangJoseph P. PintoYifan WenYuan Wangsubject
TruckPollutantAir PollutantsMultidisciplinaryMeteorologyAir pollutionCOVID-19TransportationRegression analysisModels TheoreticalParticulatesmedicine.disease_causeMachine LearningElectrificationMegacityElectricityAir PollutionPhysical SciencesmedicineHumansEnvironmental scienceParticulate MatterAir quality indexAlgorithmsVehicle Emissionsdescription
The large fluctuations in traffic during the COVID-19 pandemic provide an unparalleled opportunity to assess vehicle emission control efficacy. Here we develop a random-forest regression model, based on the large volume of real-time observational data during COVID-19, to predict surface-level NO(2), O(3), and fine particle concentration in the Los Angeles megacity. Our model exhibits high fidelity in reproducing pollutant concentrations in the Los Angeles Basin and identifies major factors controlling each species. During the strictest lockdown period, traffic reduction led to decreases in NO(2) and particulate matter with aerodynamic diameters <2.5 μm by –30.1% and –17.5%, respectively, but a 5.7% increase in O(3). Heavy-duty truck emissions contribute primarily to these variations. Future traffic-emission controls are estimated to impose similar effects as observed during the COVID-19 lockdown, but with smaller magnitude. Vehicular electrification will achieve further alleviation of NO(2) levels.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2021-06-21 | Proceedings of the National Academy of Sciences |