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Saqer R, Issa S, Saleous N. Spatio-temporal characterization of PM10 concentration across Abu Dhabi Emirate (UAE). Heliyon 2024; 10:e32812. [PMID: 39022071 PMCID: PMC11253230 DOI: 10.1016/j.heliyon.2024.e32812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2024] [Revised: 06/08/2024] [Accepted: 06/10/2024] [Indexed: 07/20/2024] Open
Abstract
The abundance and recurrence of particulate matter in Abu Dhabi Emirate (ADE), are often derived from different emission sources such as the combustion of hydrocarbon, producing much of the PM2.5 found in outdoor air, as well as a significant proportion of PM10. Wind-blown dust from open desert areas and construction sites, landfills and agriculture, brush/waste burning, and industrial sources, has contributed markedly to the problem of the spread of haze and the long-range movement of pollutants in the country. In this study, the spatio-temporal characterization of PM10 concentration across the Emirate was analyzed utilizing geospatial interpolation, spanning the period between 2013 and 2017. The results suggest that the fluctuations of the PM10 concentration can be decomposed into three dominant types, each characterizing different spatial and temporal variations. First, the western region with PM10 showing a peak concentration during the summer season i.e., when the winds are predominantly northerlies or northwesterly, and a minimal concentration during the winter season. Second, the central region with the PM10 exhibiting a concentration surge in July-August, as a result of a mix of strong winds and high temperatures. Third, the eastern region with a low concentration of PM10. Seasonally, this component exhibits two concentration maxima during quarters 2 and 3 (summer), and two minima during quarters 1 and 4 (winter). Indeed, the seasonal variability of PM10 concentration in desertic countries like the UAE is closely linked to the seasonal variation of heat waves and dust storms, which are characteristic of the dryland climate. During the summer months, the UAE experiences high temperatures and arid conditions, creating favorable conditions for the formation of heat waves. Furthermore, it was noticed that the PM10 concentration also fluctuated markedly throughout the study period with anomalies detected in open desert areas and regions characterized by extensive industrial operations.
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Affiliation(s)
- Rana Saqer
- Department of Geosciences, College of Science, United Arab Emirates University, P. O. Box 15551, Al Ain, United Arab Emirates
- Petroleum Engineering Technology Department, Abu Dhabi Polytechnic, P.O. Box 111499, Abu Dhabi, United Arab Emirates
| | - Salem Issa
- Department of Geosciences, College of Science, United Arab Emirates University, P. O. Box 15551, Al Ain, United Arab Emirates
| | - Nazmi Saleous
- Department of Geography and Urban Sustainability, United Arab Emirates University, P. O. Box 15551, Al Ain, United Arab Emirates
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AlShehhi A, Welsch R. Artificial intelligence for improving Nitrogen Dioxide forecasting of Abu Dhabi environment agency ground-based stations. JOURNAL OF BIG DATA 2023; 10:92. [PMID: 37303479 PMCID: PMC10236404 DOI: 10.1186/s40537-023-00754-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 05/08/2023] [Indexed: 06/13/2023]
Abstract
Nitrogen Dioxide (NO2 ) is a common air pollutant associated with several adverse health problems such as pediatric asthma, cardiovascular mortality,and respiratory mortality. Due to the urgent society's need to reduce pollutant concentration, several scientific efforts have been allocated to understand pollutant patterns and predict pollutants' future concentrations using machine learning and deep learning techniques. The latter techniques have recently gained much attention due it's capability to tackle complex and challenging problems in computer vision, natural language processing, etc. In the NO2 context, there is still a research gap in adopting those advanced methods to predict the concentration of pollutants. This study fills in the gap by comparing the performance of several state-of-the-art artificial intelligence models that haven't been adopted in this context yet. The models were trained using time series cross-validation on a rolling base and tested across different periods using NO2 data from 20 monitoring ground-based stations collected by Environment Agency- Abu Dhabi, United Arab Emirates. Using the seasonal Mann-Kendall trend test and Sen's slope estimator, we further explored and investigated the pollutants trends across the different stations. This study is the first comprehensive study that reported the temporal characteristic of NO2 across seven environmental assessment points and compared the performance of the state-of-the-art deep learning models for predicting the pollutants' future concentration. Our results reveal a difference in the pollutants concentrations level due to the geographic location of the different stations, with a statistically significant decrease in the NO2 annual trend for the majority of the stations. Overall, NO2 concentrations exhibit a similar daily and weekly pattern across the different stations, with an increase in the pollutants level during the early morning and the first working day. Comparing the state-of-the-art model performance transformer model demonstrate the superiority of ( MAE:0.04 (± 0.04),MSE:0.06 (± 0.04), RMSE:0.001 (± 0.01), R2 : 0.98 (± 0.05)), compared with LSTM (MAE:0.26 (± 0.19), MSE:0.31 (± 0.21), RMSE:0.14 (± 0.17), R2 : 0.56 (± 0.33)), InceptionTime (MAE: 0.19 (± 0.18), MSE: 0.22 (± 0.18), RMSE:0.08 (± 0.13), R2 :0.38 (± 1.35) ), ResNet (MAE:0.24 (± 0.16), MSE:0.28 (± 0.16), RMSE:0.11 (± 0.12), R2 :0.35 (± 1.19) ), XceptionTime (MAE:0.7 (± 0.55), MSE:0.79 (± 0.54), RMSE:0.91 (± 1.06), R2 : - 4.83 (± 9.38) ), and MiniRocket (MAE:0.21 (± 0.07), MSE:0.26 (± 0.08), RMSE:0.07 (± 0.04), R2 : 0.65 (± 0.28) ) to tackle this challenge. The transformer model is a powerful model for improving the accurate forecast of the NO2 levels and could strengthen the current monitoring system to control and manage the air quality in the region. Supplementary Information The online version contains supplementary material available at 10.1186/s40537-023-00754-z.
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Affiliation(s)
- Aamna AlShehhi
- Biomedical Engineering, Khalifa University, Abu Dhabi, United Arab Emirates
| | - Roy Welsch
- Sloan School of Management and Statistics, Massachusetts Institute of Technology, Cambridge, Massachusetts USA
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Hasnain A, Sheng Y, Hashmi MZ, Bhatti UA, Ahmed Z, Zha Y. Assessing the ambient air quality patterns associated to the COVID-19 outbreak in the Yangtze River Delta: A random forest approach. CHEMOSPHERE 2023; 314:137638. [PMID: 36565760 PMCID: PMC9770002 DOI: 10.1016/j.chemosphere.2022.137638] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/15/2022] [Revised: 12/08/2022] [Accepted: 12/21/2022] [Indexed: 06/17/2023]
Abstract
The novel coronavirus (COVID-19), first identified at the end of December 2019, has significant impacts on all aspects of human society. In this study, we aimed to assess the ambient air quality patterns associated to the COVID-19 outbreak in the Yangtze River Delta (YRD) region using a random forest (RF) model. To estimate the accuracy of the model, the cross-validation (CV), determination coefficient R2, root mean squared error (RMSE) and mean absolute error (MAE) were used. The results demonstrate that the RF model achieved the best performance in the prediction of PM10 (R2 = 0.78, RMSE = 8.81 μg/m3), PM2.5 (R2 = 0.76, RMSE = 6.16 μg/m3), SO2 (R2 = 0.76, RMSE = 0.70 μg/m3), NO2 (R2 = 0.75, RMSE = 4.25 μg/m3), CO (R2 = 0.81, RMSE = 0.4 μg/m3) and O3 (R2 = 0.79, RMSE = 6.24 μg/m3) concentrations in the YRD region. Compared with the prior two years (2018-19), significant reductions were recorded in air pollutants, such as SO2 (-36.37%), followed by PM10 (-33.95%), PM2.5 (-32.86%), NO2 (-32.65%) and CO (-20.48%), while an increase in O3 was observed (6.70%) during the COVID-19 period (first phase). Moreover, the YRD experienced rising trends in the concentrations of PM10, PM2.5, NO2 and CO, while SO2 and O3 levels decreased in 2021-22 (second phase). These findings provide credible outcomes and encourage the efforts to mitigate air pollution problems in the future.
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Affiliation(s)
- Ahmad Hasnain
- Key Laboratory of Virtual Geographic Environment, Ministry of Education, Nanjing Normal University, Nanjing 210023, China; School of Geography, Nanjing Normal University, Nanjing 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information, Resource Development and Application, Nanjing 210023, China
| | - Yehua Sheng
- Key Laboratory of Virtual Geographic Environment, Ministry of Education, Nanjing Normal University, Nanjing 210023, China; School of Geography, Nanjing Normal University, Nanjing 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information, Resource Development and Application, Nanjing 210023, China.
| | | | - Uzair Aslam Bhatti
- School of Information and Communication Engineering, Hainan University, Haikou, China
| | - Zulkifl Ahmed
- Department of Civil Technology, Mir Chakar Khan Rind University of Technology, DG Khan 32200, Pakistan
| | - Yong Zha
- Key Laboratory of Virtual Geographic Environment, Ministry of Education, Nanjing Normal University, Nanjing 210023, China; School of Geography, Nanjing Normal University, Nanjing 210023, China; Jiangsu Center for Collaborative Innovation in Geographical Information, Resource Development and Application, Nanjing 210023, China
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Fayaz M. The lock-down effects of COVID-19 on the air pollution indices in Iran and its neighbors. MODELING EARTH SYSTEMS AND ENVIRONMENT 2022; 9:669-675. [PMID: 36157916 PMCID: PMC9483498 DOI: 10.1007/s40808-022-01528-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/02/2022] [Accepted: 09/06/2022] [Indexed: 11/29/2022]
Abstract
Introduction The COVID-19 restrictions have a lot of various peripheral negative and positive effects, like economic shocks and decreasing air pollution, respectively. Many studies showed NO2 reduction in most parts of the world. Methods Iran and its land and maritime neighbors have about 7.4% of the world population and 6.3% and 5.8% of World COVID-19 cases and deaths, respectively. The air pollution indices of them such as CH4 (Methane), CO_1 (CO), H2O (Water), HCHO (Tropospheric Atmospheric Formaldehyde), NO2 (Nitrogen oxides), O3 (ozone), SO2 (Sulfur Dioxide), UVAI_AAI [UV Aerosol Index (UVAI)/Absorbing Aerosol Index (AAI)] are studied from the First quarter of 2019 to the fourth quarter of 2021 with Copernicus Sentinel 5 Precursor (S5P) satellite data set from Google Earth Engine. The outliers are detected based on the depth functions. We use a two-sample t test, Wilcoxon test, and interval-wise testing for functional data to control the familywise error rate. Result The adjusted p value comparison between Q2 of 2019 and Q2 of 2020 in NO2 for almost all countries is statistically significant except Iraq, UAE, Bahrain, Qatar, and Kuwait. But, the CO and HCHO are not statistically significant in any country. Although CH4, O3, and UVAI_AAI are statistically significant for some countries. In the Q2 comparison for NO2 between 2020 and 2021, only Iran, Armenia, Turkey, UAE, and Saudi Arabia are statistically significant. However, Ch4 is statistically significant for all countries except Azerbaijan. Conclusions The comparison with and without adjusted p values declares the decreases in some air pollution in these countries. Supplementary Information The online version contains supplementary material available at 10.1007/s40808-022-01528-x.
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Affiliation(s)
- Mohammad Fayaz
- Department of Biostatistics, School of Allied Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Sönmez VZ, Ayvaz C, Ercan N, Sivri N. Evaluation of Istanbul from the environmental components' perspective: what has changed during the pandemic? ENVIRONMENTAL MONITORING AND ASSESSMENT 2022; 194:462. [PMID: 35644795 PMCID: PMC9148846 DOI: 10.1007/s10661-022-10105-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/07/2022] [Accepted: 05/15/2022] [Indexed: 06/15/2023]
Abstract
This study aims to determine the 1-year change over the pandemic period in Istanbul, the megacity with the highest population in Turkey, based on environmental components. Among the environmental topics, water consumption habits, changes in air quality, changes due to noise elements, and most importantly, the changes in usage habits of disposable plastic materials that directly affect health have been revealed. The results obtained showed that, in Istanbul, 8.1 × 108 gloves should be considered waste, and considering the population living in districts along coastal areas, the number of waste masks that are likely to end up in the sea was 325.648 pieces/day. The results of the air quality and noise measurements during the pandemic showed that reductions in parallel with human activities were recorded with the lockdown effect. The average noise values of the districts along both sides of the Bosporus, where urbanization is concentrated, were between 50 and 59 dB. The precautions taken during the pandemic have had an effective role in reducing air pollution in Istanbul. In the measurements, the parameters with effective reductions were PM10 (7-47%), PM2.5 (13-48%), NO2 (13-38%), and SO2 (10-56%). As a result, Istanbul's year of changes during the pandemic period, in terms of water, air, noise, and solid plastic wastes, which are the most important components of the environment, is presented.
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Affiliation(s)
- Vildan Zülal Sönmez
- Department of Environmental Engineering, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Coşkun Ayvaz
- Department of Environmental Engineering, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Nevra Ercan
- Department of Chemical Engineering, Istanbul University-Cerrahpasa, Istanbul, Turkey
| | - Nüket Sivri
- Department of Environmental Engineering, Istanbul University-Cerrahpasa, Istanbul, Turkey
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Shanableh A, Al-Ruzouq R, Hamad K, Gibril MBA, Khalil MA, Khalifa I, El Traboulsi Y, Pradhan B, Jena R, Alani S, Alhosani M, Stietiya MH, Al Bardan M, Al-Mansoori S. Effects of the COVID-19 lockdown and recovery on People's mobility and air quality in the United Arab Emirates using satellite and ground observations. REMOTE SENSING APPLICATIONS : SOCIETY AND ENVIRONMENT 2022; 26:100757. [PMID: 36281297 PMCID: PMC9581513 DOI: 10.1016/j.rsase.2022.100757] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 03/30/2022] [Accepted: 04/14/2022] [Indexed: 06/16/2023]
Abstract
The stringent COVID-19 lockdown measures in 2020 significantly impacted people's mobility and air quality worldwide. This study presents an assessment of the impacts of the lockdown and the subsequent reopening on air quality and people's mobility in the United Arab Emirates (UAE). Google's community mobility reports and UAE's government lockdown measures were used to assess the changes in the mobility patterns. Time-series and statistical analyses of various air pollutants levels (NO2, O3, SO2, PM10, and aerosol optical depth-AOD) obtained from satellite images and ground monitoring stations were used to assess air quality. The levels of pollutants during the initial lockdown (March to June 2020) and the subsequent gradual reopening in 2020 and 2021 were compared with their average levels during 2015-2019. During the lockdown, people's mobility in the workplace, parks, shops and pharmacies, transit stations, and retail and recreation sectors decreased by about 34%-79%. However, the mobility in the residential sector increased by up to 29%. The satellite-based data indicated significant reductions in NO2 (up to 22%), SO2 (up to 17%), and AOD (up to 40%) with small changes in O3 (up to 5%) during the lockdown. Similarly, data from the ground monitoring stations showed significant reductions in NO2 (49% - 57%) and PM10 (19% - 64%); however, the SO2 and O3 levels showed inconsistent trends. The ground and satellite-based air quality levels were positively correlated for NO2, PM10, and AOD. The data also demonstrated significant correlations between the mobility and NO2 and AOD levels during the lockdown and recovery periods. The study documents the impacts of the lockdown on people's mobility and air quality and provides useful data and analyses for researchers, planners, and policymakers relevant to managing risk, mobility, and air quality.
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Affiliation(s)
- Abdallah Shanableh
- Civil and Environmental Engineering Department, University of Sharjah, Sharjah, 27272, United Arab Emirates
- GIS & Remote Sensing Center, Research Institute of Sciences and Engineering, University of Sharjah, Sharjah, 27272, United Arab Emirates
| | - Rami Al-Ruzouq
- Civil and Environmental Engineering Department, University of Sharjah, Sharjah, 27272, United Arab Emirates
- GIS & Remote Sensing Center, Research Institute of Sciences and Engineering, University of Sharjah, Sharjah, 27272, United Arab Emirates
| | - Khaled Hamad
- Civil and Environmental Engineering Department, University of Sharjah, Sharjah, 27272, United Arab Emirates
| | - Mohamed Barakat A Gibril
- GIS & Remote Sensing Center, Research Institute of Sciences and Engineering, University of Sharjah, Sharjah, 27272, United Arab Emirates
- Department of Civil Engineering, Faculty of Engineering, Universiti Putra Malaysia (UPM), Serdang, 43400, Selangor, Malaysia
| | - Mohamad Ali Khalil
- GIS & Remote Sensing Center, Research Institute of Sciences and Engineering, University of Sharjah, Sharjah, 27272, United Arab Emirates
| | - Inas Khalifa
- Civil and Environmental Engineering Department, University of Sharjah, Sharjah, 27272, United Arab Emirates
| | - Yahya El Traboulsi
- Civil and Environmental Engineering Department, University of Sharjah, Sharjah, 27272, United Arab Emirates
| | - Biswajeet Pradhan
- Centre for Advanced Modelling and Geospatial Information Systems (CAMGIS), School of Civil and Environmental Engineering, Faculty of Engineering and Information Technology, University of Technology Sydney, New South Wales, Australia
- Earth Observation Center, Institute of Climate Change, Universiti Kebangsaan Malaysia, 43600, UKM, Bangi, Selangor, Malaysia
| | - Ratiranjan Jena
- GIS & Remote Sensing Center, Research Institute of Sciences and Engineering, University of Sharjah, Sharjah, 27272, United Arab Emirates
| | - Sama Alani
- Department of Civil Engineering, McMaster University, 1280 Main St W, Hamilton, ON, Canada, L8S 4L8
| | - Mohamad Alhosani
- Division of Consultancy, Research & Innovation (CRI), Sharjah Environment Company-Bee'ah, Sharjah, 20248, United Arab Emirates
| | - Mohammed Hashem Stietiya
- Division of Consultancy, Research & Innovation (CRI), Sharjah Environment Company-Bee'ah, Sharjah, 20248, United Arab Emirates
| | - Mayyada Al Bardan
- Sharjah Electricity and Water Authority, Sharjah, 135, United Arab Emirates
| | - Saeed Al-Mansoori
- Applications Development and Analysis Section (ADAS), Mohammed Bin Rashid Space Centre (MBRSC), Dubai, 211833, United Arab Emirates
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Francis D, Fonseca R, Nelli N, Teixido O, Mohamed R, Perry R. Increased Shamal winds and dust activity over the Arabian Peninsula during the COVID-19 lockdown period in 2020. AEOLIAN RESEARCH 2022; 55:100786. [PMID: 35251380 PMCID: PMC8883805 DOI: 10.1016/j.aeolia.2022.100786] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 02/12/2022] [Accepted: 02/22/2022] [Indexed: 06/14/2023]
Abstract
While anthropogenic pollutants have decreased during the lockdown imposed as an effort to contain the spread of the Coronavirus disease 2019 (COVID-19), changes in particulate matter (PM) do not necessarily exhibit the same tendency. This is the case for the eastern Arabian Peninsula, where in March-June 2020, and with respect to the same period in 2016-2019, a 30 % increase in PM concentration is observed. A stronger than normal nocturnal low-level jet and subtropical jet over parts of Saudi Arabia, in response to anomalous convection over the tropical Indian Ocean, promoted enhanced and more frequent episodes of Shamal winds over the Arabian Peninsula. Increased surface winds associated with the downward mixing of momentum to the surface fostered, in turn, dust lifting and increased PM concentrations. The stronger low-level winds also favoured long-range transport of aerosols, changing the PM values downstream. The competing effects of reduced anthropogenic and increased dust concentrations leave a small positive signal (<5 W m-2) in the net surface radiation flux (Rnet), with the former dominating during daytime and the latter at night. However, in parts of the Arabian Gulf, Sea of Oman and Iran Rnet increased by >20 W m-2 with respect to the baseline period, owing to a clearer environment and weaker winds. It is concluded that a reduction in anthropogenic emissions due to the lockdown does not necessarily go hand in hand with lower particulate matter concentrations. Therefore, emissions reduction strategies need to account for feedback effects in order to reach the planned long-term outcomes.
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Affiliation(s)
- Diana Francis
- Environmental and Geophysical Sciences (ENGEOS) Lab, Khalifa University of Science and Technology, P. O. Box 127788, Abu Dhabi, United Arab Emirates
| | - Ricardo Fonseca
- Environmental and Geophysical Sciences (ENGEOS) Lab, Khalifa University of Science and Technology, P. O. Box 127788, Abu Dhabi, United Arab Emirates
| | - Narendra Nelli
- Environmental and Geophysical Sciences (ENGEOS) Lab, Khalifa University of Science and Technology, P. O. Box 127788, Abu Dhabi, United Arab Emirates
| | - Oriol Teixido
- Environment Agency - Abu Dhabi (EAD), P.O Box 45553, Abu Dhabi, United Arab Emirates
| | - Ruqaya Mohamed
- Environment Agency - Abu Dhabi (EAD), P.O Box 45553, Abu Dhabi, United Arab Emirates
| | - Richard Perry
- Environment Agency - Abu Dhabi (EAD), P.O Box 45553, Abu Dhabi, United Arab Emirates
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Silva ACT, Branco PTBS, Sousa SIV. Impact of COVID-19 Pandemic on Air Quality: A Systematic Review. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2022; 19:1950. [PMID: 35206139 PMCID: PMC8871899 DOI: 10.3390/ijerph19041950] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/01/2022] [Revised: 02/02/2022] [Accepted: 02/03/2022] [Indexed: 02/07/2023]
Abstract
With the emergence of the COVID-19 pandemic, several governments imposed severe restrictions on socio-economic activities, putting most of the world population into a general lockdown in March 2020. Although scattered, studies on this topic worldwide have rapidly emerged in the literature. Hence, this systematic review aimed to identify and discuss the scientifically validated literature that evaluated the impact of the COVID-19 pandemic and associated restrictions on air quality. Thus, a total of 114 studies that quantified the impact of the COVID-19 pandemic on air quality through monitoring were selected from three databases. The most evaluated countries were India and China; all the studies intended to evaluate the impact of the pandemic on air quality, mainly concerning PM10, PM2.5, NO2, O3, CO, and SO2. Most of them focused on the 1st lockdown, comparing with the pre- and post-lockdown periods and usually in urban areas. Many studies conducted a descriptive analysis, while others complemented it with more advanced statistical analysis. Although using different methodologies, some studies reported a temporary air quality improvement during the lockdown. More studies are still needed, comparing different lockdown and lifting periods and, in other areas, for a definition of better-targeted policies to reduce air pollution.
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Affiliation(s)
- Ana Catarina T. Silva
- LEPABE—Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; (A.C.T.S.); (P.T.B.S.B.)
- ALiCE—Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Pedro T. B. S. Branco
- LEPABE—Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; (A.C.T.S.); (P.T.B.S.B.)
- ALiCE—Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Sofia I. V. Sousa
- LEPABE—Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; (A.C.T.S.); (P.T.B.S.B.)
- ALiCE—Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
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Monitoring the Impact of COVID-19 Lockdown on the Production of Nitrogen Dioxide (NO2) Pollutants Using Satellite Imagery: A Case Study of South Asia. SUSTAINABILITY 2021. [DOI: 10.3390/su13137184] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Among the numerous anthropogenic pollutants, nitrogen dioxide (NO2) is one of the leading contaminants mainly released by burning fossil fuels in industrial and transport sectors. This study evaluates the impact of COVID-19 lockdown on the growing trend of NO2 emissions in South Asia. Satellite imagery data of Sentinel-5 Precursor with Tropomi instrument was employed in this study. The analysis was performed using time series data from February–May 2019 and February–May 2020. The time frame from February–May 2020 was further divided into two sub-time-frames, i.e., from 1 February–20 March (pre-lockdown) and from 21 March–May 2020 (lockdown). Results show the concentration of NO2 pollutants over the region declined by 6.41% from February–May 2019 to February–May 2020. Interestingly, an increasing trend of NO2 concentration by 6.58% occurred during the pre-lockdown phase in 2020 (1 February–20 March) compared to 2019 (February–May). However, the concentration of NO2 pollutants reduced considerably by 21.10% during the lockdown phase (21 March–10 May) compared to the pre-lockdown phase in 2020. Furthermore, the country-specific detailed analysis demonstrates the significant impact of COVID-19-attributed lockdown on NO2 concentration in South Asia.
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