Quantifying Air Pollutant Variations during COVID-19 Lockdown in a Capital City in Northwest China DOI Creative Commons
Rong Feng, Hongmei Xu, Zexuan Wang

et al.

Atmosphere, Journal Year: 2021, Volume and Issue: 12(6), P. 788 - 788

Published: June 19, 2021

In the context of outbreak coronavirus disease 2019 (COVID-19), strict lockdown policies were implemented to control nonessential human activities in Xi’an, northwest China, which greatly limited spread pandemic and affected air quality. Compared with pre-lockdown, quality index concentrations PM2.5, PM10, SO2, CO during reduced, but reductions not very significant. NO2 levels exhibited largest decrease (52%) lockdown, owing remarkable decreased motor vehicle emissions. The highest K+ lowest Ca2+ PM2.5 samples could be attributed increase household biomass fuel consumption suburbs rural areas around Xi’an physical (e.g., travel, emissions, construction activities), respectively, period. Secondary chemical reactions atmosphere increased period, as evidenced by O3 level (increased 160%) OC/EC ratios 26%), compared pre-lockdown levels. results, based on a natural experiment this study, can used reference for studying formation source pollution provide evidence establishing future long-term policies.

Language: Английский

Particle composition, sources and evolution during the COVID-19 lockdown period in Chengdu, southwest China: Insights from single particle aerosol mass spectrometer data DOI Open Access
Junke Zhang, Huan Li, Luyao Chen

et al.

Atmospheric Environment, Journal Year: 2021, Volume and Issue: 268, P. 118844 - 118844

Published: Nov. 9, 2021

Language: Английский

Citations

31
Sources of PM2.5 and its responses to emission reduction strategies in the Central Plains Economic Region in China: Implications for the impacts of COVID-19 DOI Creative Commons
Huiyun Du, Jie Li, Zifa Wang

et al.

Environmental Pollution, Journal Year: 2021, Volume and Issue: 288, P. 117783 - 117783

Published: July 16, 2021

The Central Plains Economic Region (CPER) located along the transport path to Beijing-Tianjin-Hebei area has experienced severe PM2.5 pollution in recent years. However, few modeling studies have been performed on sources of PM2.5, especially impacts emission reduction strategies. In this study, Nested Air Quality Prediction Model System (NAQPMS) with an online tracer-tagging module was adopted investigate source sectors and a series sensitivity tests were conducted different sector-based mitigation strategies pollution. response surfaces pollutants changes built. results showed that resident-related sector (resident agriculture), fugitive dust, traffic industry emissions main Zhengzhou, contributing 49%, 19%, 15% 13%, respectively. Response Henan revealed combined efficiently decreased Zhengzhou. reduced only region barely satisfied national air quality standard 75 μg/m3, whereas 50%–60% over whole could reach goal. On severely polluted days, even 60% these two insufficient satisfy μg/m3. Moreover, resulted increase O3 concentration. surface method Zhengzhou by 19% COVID-19 lockdown, which approached observed 21%, indicating be employed study lockdown This provides scientific reference for formulation CPER.

Language: Английский

Citations

29
Airflow deflectors of external windowsto induce ventilation: Towards COVID-19 prevention and control DOI Open Access
Wanqiao Che, Junwei Ding, Liang Li

et al.

Sustainable Cities and Society, Journal Year: 2021, Volume and Issue: 77, P. 103548 - 103548

Published: Nov. 18, 2021

Language: Английский

Citations

28
Meteorology-normalized variations of air quality during the COVID-19 lockdown in three Chinese megacities DOI Open Access

Yunqian Lv,

Hezhong Tian, Lining Luo

et al.

Atmospheric Pollution Research, Journal Year: 2022, Volume and Issue: 13(6), P. 101452 - 101452

Published: May 14, 2022

Language: Английский

Citations

19
Air Quality Index (AQI) Did Not Improve during the COVID-19 Lockdown in Shanghai, China, in 2022, Based on Ground and TROPOMI Observations DOI Creative Commons
Qihan Ma, Jianbo Wang, Ming Xiong

et al.

Remote Sensing, Journal Year: 2023, Volume and Issue: 15(5), P. 1295 - 1295

Published: Feb. 26, 2023

The lockdowns from the coronavirus disease of 2019 (COVID-19) have led to a reduction in anthropogenic activities and hence reduced primary air pollutant emissions, which were reported helped quality improvements. However, expressed by index (AQI) did not improve Shanghai, China, during COVID-19 outbreak spring 2022. To better understand reason, we investigated variations nitrogen dioxide (NO2), ozone (O3), PM2.5 (particular matter with an aerodynamic diameter less than 2.5 μm), PM10 10 μm) using situ satellite measurements 1 March 31 June 2022 (pre-, full-, partial-, post-lockdown periods). results show that benefit significantly decreased ground-level PM2.5, PM10, NO2 was offset amplified O3 pollution, therefore leading increased AQI. According backward trajectory analyses multiple linear regression (MLR) model, emissions dominated observed changes pollutants full-lockdown period relative previous years (2019–2021), whereas long-range transport local meteorological parameters (temperature, pressure, wind speed, humidity, precipitation) influenced little. We further identified chemical mechanism caused increase concentration. pollution oxides (NOx) under VOC-limited regime high background concentrations owing seasonal variations. In addition, found downtown area, more sensitively responded lockdown measures they suburbs. These findings provide new insights into impact emission control restrictions on implications for future.

Language: Английский

Citations

12
Spatio-temporal analysis of air pollution dynamics over Bangalore city during second wave of COVID-19 DOI Creative Commons

Iranna Gogeri,

K. C. Gouda,

S.T. Aruna

et al.

Natural Hazards Research, Journal Year: 2024, Volume and Issue: 4(3), P. 401 - 412

Published: Sept. 1, 2024

The country wide lockdown implemented during 27th April to 14th June 2021 in order prevent the spread of COVID-19 second wave India. Effect restricted resulted improved air quality. This study focuses on analyzing spatio-temporal distribution analysis major pollutant concentration over Bangalore city inverse distance weighting (IDW) method is for spatial quantify concentrations at each location Urban Bangalore. research considers distinct periods pre-lockdown and pandemic investigate impact reduced human activities quality city. mainly utilizes pollution data collected from Central Pollution Control Board (CPCB) monitoring stations across Bangalore, including measurements pollutants such as PM2.5, PM10, O3, NO2, SO2, CO. IDW create high-resolution maps both periods. provides valuable insights into variations levels though out comparative reveals significant changes between two periods; similarly, temporal weekly average also witnessed negative anomalies weeks. results indicate substantial reductions lockdown, attributed decreased vehicular emissions, industrial activities, construction operations. period serves a baseline assessing improvements lockdown. modeling approach enhances our understanding patterns metropolitan findings underscore potential benefits implementing sustainable strategies maintain even after subsides.

Language: Английский

Citations

4
Characterizing vertical distribution patterns of PM2.5 in low troposphere of Shanghai city, China: Implications from the perspective of unmanned aerial vehicle observations DOI Creative Commons
Rui-feng Song,

Dongsheng Wang,

Xiaobing Li

et al.

Atmospheric Environment, Journal Year: 2021, Volume and Issue: 265, P. 118724 - 118724

Published: Sept. 14, 2021

Language: Английский

Citations

27
Assessing the effects of short-term traffic restriction policies on traffic-related air pollutants DOI

Xiao-rui Fang,

Xing-hang Zhu,

Xingzhou Li

et al.

The Science of The Total Environment, Journal Year: 2023, Volume and Issue: 867, P. 161451 - 161451

Published: Jan. 5, 2023

Language: Английский

Citations

10
UFORE-D Modeling of Urban Tree Influence on Particulate Matter Concentrations in a High-Altitude Latin American Megacity DOI Creative Commons

Laura Marcela Ochoa-Alvarado,

Juan Garzón-Gil,

Sergio Castro-Alzate

et al.

Earth, Journal Year: 2025, Volume and Issue: 6(2), P. 36 - 36

Published: May 9, 2025

Urban trees reduce particulate matter (PM) concentrations through dry deposition, interception, and modifying wind patterns, improving air quality saving public health expenses in urban planning. The main objective of this article is to present an analysis the influence on PM10 PM2.5 a high-altitude Latin American megacity (Bogotá, Colombia) using UFORE-D modeling. Six PM monitoring stations distributed throughout were used. Hourly climatic data collected for seven years, along with dendrometric cartographic analyses within 200 m stations. Land cover was quantified satellite imagery (Landsat 8) order perform spatial analysis. results showed that model effectively forest canopy area (CA) impact removal, showing strong correlations (R2 = 0.987 0.918). removal increased both CA ambient pollutant concentrations, exhibiting greater influence. Sensitivity highlighted enhanced leaf index (LAI: 2–4 m2/m2), particularly at higher speeds. (1.05 ± 0.01%) per unit exceeded (0.71 0.09%), potentially due resuspension Model validation confirmed reliability across settings, emphasizing its utility Scenario (E1–E4, CA: 8.30–95.4%) demonstrated consistent positive correlation between diminishing returns extreme levels. constraints suggested integrated green infrastructure solutions. Although improved rates, absolute reduction pollutants remained limited, suggesting comprehensive emission monitoring.

Language: Английский

Citations

0
Impact of COVID-19 lockdown on NO2 and PM2.5 exposure inequalities in London, UK DOI Open Access

Vasilis Kazakos,

Jonathon Taylor, Zhiwen Luo

et al.

Environmental Research, Journal Year: 2021, Volume and Issue: 198, P. 111236 - 111236

Published: May 3, 2021

Language: Английский

Citations

22