Spatiotemporal variations and source apportionment of NOx, SO2, and O3 emissions around heavily industrial locality

Abstract

The main objective of this study is to estimate the levels of pollution to which the community is presently exposed and to model the regimes of local air quality. Diurnal, daily, and monthly variations of NO, NO2, SO2, and O3 were thoroughly investigated in three areas; namely, residential, industrial, and terminal in Ras Al-Khafji. There is obvious diurnal variation in the concentration of these pollutants that clearly follows the diurnal variation of atmospheric temperature and main anthropogenic and industrial activities. Correlation analysis showed that meteorological conditions play a vital role in shaping the pattern and transportation of air pollutants and photochemical processes affecting O3 formation and destruction. Bivariate polar plots, an effective graphical tool that utilizes air pollutant concentrations' dependence on wind speed and wind direction, were used to identify prevailing emission sources. Non-buoyant ground-level sources like domestic heating and street transport emissions, various industrial stacks, and airport-related activities were considered dominant emission sources in observatory sites. This study offers valuable and detailed information on the status of air quality, which has considerable, quantifiable, and important public health benefits.

Feature analysis on air quality in the main urban area of Nanchong City in 2015–2018

“…5(d)). However, the diurnal variation distribution of SO 2 is different from the bimodal distribution in some studies [25,57], due to the fact that Nanchong City is a large agricultural city with underdeveloped industries, and the phenomenon of morning and evening peak caused by human activities is not obvious. SO 2 concentration in the evening is substantially higher than that in the daytime because of the existence of SO 2 in the evening and the better conditions for pollutant diffusion in the daytime than in the evening [60].…”

“…Under high temperature and strong solar radiation, NOx and VOCs easily develop photochemical reactions to produce O 3 [5,56]. Wind also has a positive effect on O 3 [31,57]; specifically, there is an obvious positive correlation between wind speed and O 3 (r = 0.44, p < 0.01) (Table S3). For this reason, O 3 concentration in spring and summer increases greatly, and the peak concentration occurs in July and August.…”

“…In China, secondary particulates are typically generated by oxidative reaction[78]. With its strong oxidation property, O 3 is the major oxidizing agent in the atmosphere, and it can cause indirect effects on the formation of secondary particulates[57]. The concentration change of secondary PM 2.5 is obvious, indicating that atmospheric oxidation is strengthened with the increase in O 3 concentration, which in turn increases the generation of secondary PM 2.5 .…”

Immission levels and identification of sulfur dioxide sources in La Oroya city, Peruvian Andes

“…The results of the multiple comparison test confirmed that the red cluster (CL1) contributed more to the concentrations of SO 2 , which is associated with emissions from heavy and light vehicle traffic, with contributions from the CMLO and with emissions from train traffic. Clusters 2 and 3 also showed significant differences at 5%; however, their average values and behavior are similar, which may indicate predominant emission sources with similarity for both clusters or the absence of important sources in the directions they represent (Al-Harbi et al, 2020 ). The Mann–Whitney U test proves to be an effective tool for determining significant differences between clusters (Chávez, 2020 ).…”

Tropospheric NO2 Pollution Monitoring with the GF-5 Satellite Environmental Trace Gases Monitoring Instrument over the North China Plain during Winter 2018–2019

“…Natural emission sources include lightning, which promotes the transformation of nitrogen into nitrogen oxides, and forest fires, which lead to the combustion of biomass and the production of NO 2 [7]. Human activities, such as the burning of fossil fuels and industrial activities, are the main causes of increases in NO 2 concentrations in the troposphere [8]. Therefore, in areas such as eastern China, eastern US, eastern India, and the Persian Gulf, where the population is relatively large, transportation networks are well developed, and industrialization is relatively concentrated, high concentrations of NO 2 are typically found [9,10].…”