Empirical evidence shows that air quality changes during COVID-19 pandemic lockdown in Jakarta, Indonesia are due to seasonal variation, not restricted movements

Abstract

Implementing a lockdown or activity restriction to reduce the spread of COVID-19 cases is assumed to improve air quality in highly populated cities. The effect of lockdown on air quality is often quantified by comparing pre- and during-lockdown air quality parameters without considering confounding meteorological factors. We demonstrated that rainfall can explain changes in PM10 and PM2.5 parameters in the city of Jakarta during lockdown. This article shows that comparing air quality pre- and during lockdown is misleading. Variables affecting air quality such as meteorological variables should be taken into account. The air quality in Jakarta as measured by PM10 and PM2.5 did not change significantly during the lockdown period after removing the seasonal effect.

Keywords: Air quality; COVID-19; Coronavirus; Environmental health; PM2.5; Pandemic.

Fig. 1

PM2.5 data of Milano Pascal Citta Studi in 2020. The red dots represent the control period, the green period was partial lockdown (PL) and the blue dots were total lockdown (TL). (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)

Fig. 2

Daily PM2.5 and PM10 data in Jakarta from January 1, 2016 until December 31, 2020.

Fig. 3

Daily PM2.5 and PM10 of Jakarta in 2020. The green dots represent the pre-lockdown period and the red dots represent the pre-lockdown period. The line represents a linear trend between pre and during lockdown period. (For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article.)

Fig. 4

Monthly PM2.5 and PM10 values and rainfall from January 2016 to December 2020.