Monitoring the temporal variations of PM_2.5 and gases close to the highway in Sohar, Oman

Abstract

The aim of this study was to identify the relationship between the concentrations of PM_2.5 (particulate matter less than 2.5 μm) and the temporal variation of the monitored gases at Sohar highway, Oman, from November 2014 to February 2015. The hourly concentrations of surface ozone (O₃), nitric dioxide (NO₂) and sulphur dioxide (SO₂) were measured by an open-path differential optical absorption spectroscopy instrument installed across Sohar highway. Additionally, the same gases and the meteorological parameters were measured in the same location of the PM_2.5 analyser. The findings of this study show that on the hourly time scale, PM_2.5 and O₃ were very weakly and negatively correlated. In contrast, on the daily time scale, PM_2.5 and O₃ were positively rather weakly correlated. Stronger correlation coefficient was found between 24 h averages of PM_2.5 and daily maximum O₃ concentrations. A policy implication of these findings could be that reducing the emissions of O₃ precursors reduces the levels of PM_2.5 as well.

Keywords:

• PM_2.5
• O₃
• DOAS
• BAM
• Traffic
• Emissions

Acknowledgements

Thanks to Rabbiallah for the great support.

Disclosure statement

No potential conflict of interest was reported by the author.

Additional information

Funding

The research leading to these results has received research project grant funding from The Research Council of the Sultanate of Oman, research grant agreement no [ORG SU EBR 12 013].