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PM2.5 VARIATION ESTIMATED FROM MODIS AEROSOL DATA: A CASE STUDY OF THE NORTH OF VIETNAM

PM2.5 refers to particulate matter (PM) with a diameter of smaller than 2.5 micrometers flying in the atmosphere. The high concentration of PM2.5 seriously affects the health of people and animals. Using Aerosol Optical Depth (AOD) index achieved from satellite images is possible to estimate and monitor the variation of PM2.5. This study observes the variation of AOD and the maximum PM2.5 concentration over three sub-regions in northern Vietnam based on the daily MODIS aerosol product and PM2.5 measured at a ground station. The experiment shows that the critical PM2.5 pollution is in the Red river delta during April due to the highly industrial cities, dense traffic transportation, and residue burning after agricultural harvesting. This study is an example of the capacities of using satellite data to monitor air pollution and it opens future studies on assessing the long-term trade-off between social, economic development and environment.