Effects of local biomass burning on PM2.5 and PM10 levels in Hanoi

Rice straw burning is one of the major types of biomass burning in Vietnam and other countries in Asia, which emits a large amount of air pollutants. Hanoi, capital of Vietnam, was reported as one of the most polluted cities in the region. Air quality of the city is considered to be affected by rice straw burning activities from agricultural area nearby. In this study, we determine the effect of rice straw burning on PM₁₀ and PM_2.5 levels in Hanoi by multiple linear regression analysis using R software. Ground-based PM_2.5 and PM₁₀ concentration were measured at urban site in Hanoi. Monthly variation burning hotspots of two satellite data, Moderate Resolution Imaging Spectroradiometer (MODIS) and Visible/Infrared Imager/Radiometer Suite (VIIRS) were compared in 2016, 2017 year. The results show that the number of hotspots detected by VIIRS satellite reflected the intensive burning period in reality better than MODIS one. The meteorological parameters could explain only 37% and 55% the day-to-day variation in PM_2.5 and of PM₁₀ concentration, respectively in burning period (May 2017). Daily hotspots counts in conjunction with meteorology data could explain over 85% and 82% of the variances of 24-hr PM_2.5 and PM₁₀ concentration, respectively of the same period. This is the first-time the magnitude of biomass burning in the North of Vietnam can be quantitative that proven to be related to air quality.