Last modified: 2021-03-05
Abstract
The Impact of Covid-19 lockdowns on the Quality of PM (Particulate Matter) pollution in Addis Ababa
Authors list: A. Kumie1, D. Siraw1, A. Worku1, G. Boja1, K. Dessie2, J. M. Samet3, K. T. Berhane4; J. Patz5
1Addis Ababa University, Addis Ababa, ETHIOPIA, 2University of Southern, California, CA, 3University of Colorado, Colorado, CO, 4Columbia University, New York, NY, 5University of Wisconsin, Madison, WI,
Background: The COVID-19 outbreak has spread rapidly across the world and due to this country, all over the world have implemented a lockdown strategy to slow down the spread of the disease. Ethiopian has confirmed the first COVID-19 case on March 13, 2020 and since then to control the rapid dispersion of the virus, the country imposed partial lockdown policies from on March 17 2020. This has led to reduce human activities and movement of vehicles in the city of Addis Ababa.
Objective: The aim of this study is to investigate the air quality changes during the COVID-19 lockdowns, in Addis Ababa, Ethiopia.
Methods: Air pollution monitor known as Beta Attenuator Monitor (BAM-1022) which is located inside the Tikur Anbesa Hospital Specialized Hospital (TASH) premise of Addis Ababa University has been used to measure the real time PM2.5 concentration. Three data sets were used for analysis; before COVID lockdown (Jan 1 to March 16, 2020), During lockdown (March 17-May 26, 2020) and after lockdown (May 27 to June 30, 2020).
Results: From our study, we have found that PM2.5 emissions has been reduced significantly by 11% in March compared with the 2018 same month, 28% lower in April 2020 when compared with the same months of 2017-2018, by 22% lower in May 2020 and 23% lower in June when compared with same months of the year 2017– 2019. The independent sample t-test result done for the lockdown months (March to May) with the previous years of same months shows a significant reduction (p<0.05). The lockdown period has a significant PM2.5 reduction (13%) compared with before lockdown period and 41% reduction compared with after lockdown period. Again, the result was statistically supported and found it significant (p<0.05).
Conclusions: our study finding shows that during COVID-19 lockdown period in Addis Ababa, air quality improvement in terms of PM pollution was substantial. Most important reason for the reduction could be restriction measures taken on movement of peoples and vehicles in the city as an epidemic prevention and control measures.
Key Words: air pollution, COVID -19, Lockdown, PM2.5 concentration