The Influence of Madden Julian Oscillation on The Variability of Particulate Matter 2.5 Concentration in Indonesian Maritime Continent
Deta Ewila Sinuraya(a*), Rachmy Fitriani(a), Faiz Rohman Fajary(a)

a) Department of Meteorology, Faculty of Earth Science and Technology, Bandung Institute of Technology *detaewilabrsinuraya[at]gmail.com

Abstract

Indonesia is the country that has the highest ranking in Southeast Asia in PM2.5 pollution. PM2.5 concentration can be decreased through various processes, one of which is wet deposition through the rain. Rainfall in Indonesia is affected by a very complex phenomenon, one of which is the Madden Julian Oscillation (MJO). MJO affects rainfall anomalies in the area it passes through. The increase and decrease of rainfall due to the MJO is thought to have influenced the distribution of PM2.5 in Indonesia. This research is conducted to study how MJO influences PM2.5 concentrations in the Indonesian Maritime Continent during the wet and dry seasons. Surface PM2.5 concentration data from the reanalysis of MERRA-2 M2R1NXAER data, MSWEP rainfall data, and MJO data index from Bureau of Meteorology Australia in 1980-2018 were processed using composite analysis and correlation of rainfall anomaly and PM2.5 anomaly to see the effect of active MJO on PM2.5 concentration and its constituent components in the wet and dry seasons. The anomaly values of rainfall and PM2.5 were obtained by performing a bandpass filtering (20-70 days). Before doing a bandpass filter, the mean and first three harmonic of the annual cycle is removed to eliminate unwanted variability. The results of this study indicate that the PM2.5 concentration anomaly is higher in the dry season than in the wet season. in the wet season, the PM2.5 concentration has a positive anomaly in phase 7 and a negative in phase 4 in most parts of Indonesia. In the dry season, positive anomalies occur in phases 6-8 and negative anomalies in phases 1-4 in most northern Indonesia. PM2.5 anomaly responses due to rainfall anomalies in the wet and dry seasons mostly show a negative correlation in Indonesia, covering the areas of Kalimantan, Papua, Sumatra, and Sulawesi.

Keywords: Indonesia- Madden Julian Oscillation- MERRA-2- PM2.5- Rainfall anomaly

Topic: Atmospheric Sciences