Assessing Air Quality Variation Focusing on Criteria Pollutants in Metropolitan City, Addis Ababa, Ethiopia

The issue of air pollution in urban areas is a significant environmental concern, particularly in developing nations such as Ethiopia. So that, this study analyzed Addis Ababa’s air quality for criteria pollutants, such as nitrogen dioxide (NO 2 ), surface ozone (O 3 ), carbon monoxide (CO), sulfur dioxide (SO 2 ), particulate matter 2.5 (PM 2.5 ), and particulate matter 10 (PM 10 ). This study aimed to assess the variation of these significant pollutants at different time intervals (hourly, daily, monthly, and annually) at the monitoring sites. According to the analysis results, the diurnal variation of the criteria pollutants (NO 2 , CO, PM 2.5 , and PM 10 ) was maximum during the morning and minimum during midday at all the monitoring station. However, O 3 was at its minimum in the morning and its maximum at midday; this could be due to O 3 is a secondary pollutant for the surface; it is formed from the chemical reaction of NO X and SO X . The monthly trend of PM 2.5 concentration was the most prevalent at the Old Airport from May to August, due to transportation activities, economic activities, or community activities are higher in this area than in other areas. All pollutant concentrations from September to January showed a decreasing trend, but PM 10 concentrations peaked in January due to clear and unstable atmosphere condition; as a result, the pollutant frilly dispersed. Moreover, this period known by windy, as a result might be lead to drive the particle and gaseous pollutants from land and construction areas. These pollutants showed an increasing trend over the years. Thus, it is advised to take immediate action to limit pollution in order to lessen its long‐term effects on the environment and public health.