Volume 17, Issue 4 (9-2025)
jorar 2025, 17(4): 216-220 |
Back to browse issues page
Download citation:
BibTeX | RIS | EndNote | Medlars | ProCite | Reference Manager | RefWorks
Send citation to:
BibTeX | RIS | EndNote | Medlars | ProCite | Reference Manager | RefWorks
Send citation to:
Abdollahi A A, Karimi S, Bay N, Ahmadi M, Oveisi N. Combined Hazard Analysis of Spatial Distribution of Air Pollution Index in Tehran. jorar 2025; 17 (4) :216-220
URL: http://jorar.ir/article-1-1035-en.html
URL: http://jorar.ir/article-1-1035-en.html
Faculty of Humanities, Department of Geography, Shahid Bahonar University of Kerman, Kerman, Iran
Abstract: (29 Views)
INTRODUCTION: Urban air pollution, especially in densely populated metropolises such as Tehran, has become one of the most serious environmental and health challenges. NO2, as one of the most important pollutants resulting from human activities, accumulates persistently in the surface layers of the atmosphere, especially in the cold seasons and under temperature inversion conditions. This study aims to analyze the combined risk of spatial and temporal distribution of NO2 in the cold seasons in Tehran city over a 7-year period (2018–2024) and to investigate the interaction between human and natural factors in the formation of this risk.
METHODS: In this descriptive-analytical study with an integrated approach, daily NO2 concentration data were extracted from Sentinel-5P satellite images (TROPOMI sensor) in Tehran during the winter season from 2018 to 2024 (equivalent to 1397–1403 solar year).
Using spatial extraction tools in the GIS environment, data were processed, seasonal averages were calculated, and raster-to-vector conversion was performed, and spatial and temporal distribution patterns of NO2 were plotted and analyzed.
FINDINGS: The findings showed that the distribution pattern of NO2 has undergone significant spatial and temporal changes over the seven years, with the highest concentrations observed in central Tehran and northeastern regions in 2018 and 2019. In 2020 and 2021, coinciding with the restrictions imposed during the COVID-19 era, a significant decrease in pollution levels was observed, but since 2022, NO2 concentrations have increased again, and in 2024, a significant increase was observed in the southern and eastern regions. These changes indicate a shift in pollution centers from the city center to the suburbs and a return to a centralized pattern, which indicates extensive urban development and increased human activities in peripheral areas.
CONCLUSION: According to the research results, NO2 pollution in Tehran is the consequence of a complex interaction between human factors (such as traffic, industry, and urban development) and natural conditions (temperature inversion and topography), therefore, it is considered a "combined hazard." Changes in spatial patterns of NO2 are a reflection of urban physical-functional developments and management policies
METHODS: In this descriptive-analytical study with an integrated approach, daily NO2 concentration data were extracted from Sentinel-5P satellite images (TROPOMI sensor) in Tehran during the winter season from 2018 to 2024 (equivalent to 1397–1403 solar year).
Using spatial extraction tools in the GIS environment, data were processed, seasonal averages were calculated, and raster-to-vector conversion was performed, and spatial and temporal distribution patterns of NO2 were plotted and analyzed.
FINDINGS: The findings showed that the distribution pattern of NO2 has undergone significant spatial and temporal changes over the seven years, with the highest concentrations observed in central Tehran and northeastern regions in 2018 and 2019. In 2020 and 2021, coinciding with the restrictions imposed during the COVID-19 era, a significant decrease in pollution levels was observed, but since 2022, NO2 concentrations have increased again, and in 2024, a significant increase was observed in the southern and eastern regions. These changes indicate a shift in pollution centers from the city center to the suburbs and a return to a centralized pattern, which indicates extensive urban development and increased human activities in peripheral areas.
CONCLUSION: According to the research results, NO2 pollution in Tehran is the consequence of a complex interaction between human factors (such as traffic, industry, and urban development) and natural conditions (temperature inversion and topography), therefore, it is considered a "combined hazard." Changes in spatial patterns of NO2 are a reflection of urban physical-functional developments and management policies
Article Type: Research article |
Subject:
Environmental disasters
References
1. Qanbari, A., Isa Zadeh, V. [Modeling the concentration density of ozone and nitrogen oxide pollutants in GIS and comparison of these pollutant concentrations with Sentinel-5 product in Google Earth: Case study of Tehran (Persian)]. Journal of Geographical Data (SEPEHR), 2021; 30 (118):1-20. [DOI:10.22131/sepehr.2021.246154]
2. Rahimi J., Rahimi S. [Investigating the impacts of urban spatial development on air pollution in Tehran metropolis (Persian)]. In Proceedings of the 4th Conference on Engineering Geology. Tehran, Iran. 2010:115-124.
3. Abdolazimi, H., Hadi F., Rousta H., Mokhtari, N. [Monitoring the concentration of nitrogen dioxide during the COVID-19 period using Sentinel-5 satellite data (Case study: Shiraz metropolis) (Persian)]. Journal of Natural Environmental Hazards, 2023;12(38): 1-20.
4. Shah Mohammadi, A., Bayat, A., Meshkati Zadeh Maleki, S. [Investigation of air pollution in Tabriz city using estimation of nitrogen dioxide from OMI sensor (Persian)]. Geography and Urban Planning Journal, 2020; 24(71): 201-219.
5. Sheybazi, H. [Optimal level of public transportation fare subsidy (Case study: Tehran metropolis) (Persian)]. Journal of Transportation Research, 2024; 21(1): 78-92.
6. Mintz, D. (2012). Technical assistance document for the reporting of daily air quality-the air quality index (AQI) (EPA-454/B-12-001). U.S. Environmental Protection Agency, Office of Air Quality Planning and Standards.
7. Sajadian, N. [Prediction of air pollution caused by urban transport in Tehran metropolis using the combination of GIS with LUR model and artificial neural network (Persian)]. Journal of Geographical Data (SEPEHR), 2015; 24(95):108-120 [DOI:10.22131/sepehr.2015.15556]
8. Ruggieri, M., Plaia, A. An aggregate AQI: Comparing different standardization and introducing a variability index. Science of the Total Environment, 2012; 420: 263-272. [DOI:10.1016/j.scitotenv.2012.01.028]
9. Lelieveld, J., Haines, A., Pozzer, A. Age-dependent health risk from ambient air pollution: A modelling and data analysis of childhood mortality in middle-income and low-income countries. Lancet Planetary Health, 2018; 2(7): e292-e300 [DOI:10.1016/S2542-5196(18)30147-5]
10. Xiao H., Lei T., Hulihing Z., Yu J, et al. Characteristics of surface ozone and nitrogen oxides at urban, suburban and rural sites in Ningbo, China. Atmospheric Research, 2016; 183: 236-249. [DOI:10.1016/j.atmosres.2016.09.005]
11. Shami S., Khoshlahjeh M., Ghorbani Z., et al. [Evaluation of air pollution contributes for the COVID-19 pandemic in Iran using Sentinel-5 satellite data (Persian)]. Iranian Journal of Space Science and Geomatics (JGST), 2021;10(3): 35-146 Available from: http://jgst.issge.ir/article-1-962-fa.html
12. Ruggieri M. Air pollution and health: A global concern. Environmental Health Perspectives, 2012; 120(1): A12-A13 [DOI:10.1289/ehp.1104550]
13. Statistical Center of Iran. [National Population and Housing Census (Persian)]. 2016 Available from: https://amar.org.ir
14. Bay N, Bahiraee H, Abbasi Semnani A., Kargar B. [Synoptic analysis of air pollution days in Tehran city (Persian)]. 11th Congress of Iranian Geographers, 2011
| Rights and permissions | |
 |
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License. |
