Assessment of Ambient Particulate Matter Concentrations- PM10, PM2.5 and PM1 at Rinchending in Phuentsholing, Bhutan
Keywords:Particulate matter; Wind rose diagram; Biomass burning; WHO, Diurnal cycle; Seasonal cycle, Monthly variations
AbstractThis paper presents the analysis and interpretation of daily, monthly and seasonal cycle of 1- minute average Particulate Matter (PM10, PM2.5 and PM1) concentrations measured in Rinchending, located on the hilltop, 4 km away from Phuentsholing, the second largest city in Bhutan between the period of March 2018 to March 2019. In diurnal cycle, the highest concentrations of PM were observed between 9AM – 10 AM in the morning and 5PM-7PM in the evening corresponding to the peak traffic hours. The concentrations of PM showed highest in the post-monsoon season, corresponding to October to February in Bhutan (PM10=57.36 μg/m3, PM2.5=33.73 μg/m3 and, PM1=29.28) compared to monsoon season corresponding to June-September (PM10=22.70 μg/m3, PM2.5=15.51 μg/m3 and, PM1=11.35) and pre-monsoon season corresponding to March-May (PM10=54.9 μg/m3, PM2.5=30.58 μg/m3 and, PM1=24.36). The frequency distribution of PM10 showed that upto 25% of the time, the concentration was upto 20.8 μg/m3, 50% of the time, the concentration was upto 35.3 μg/m3 and 75% of the time, the concentration was upto 59 μg/m3.Similarly, the frequency distribution of PM2.5 showed that upto 25% of the time, the concentration was upto 13.5 μg/m3, 50% of the time, the concentration was upto 22 μg/m3 and 75% of the time, the concentration was upto 38 μg/m3.The annual mean concentrations of PM10 (45.08 μg/m3) were violating the Annual WHO ambient air quality standard (20 μg/m3). The annual mean concentrations of PM2.5 (26.83μg/m3) were also violating the Annual WHO ambient air quality standard (10 μg/m3). The wind analysis done through the wind rose diagram found a dominant south and south-west wind pattern.
How to Cite
Copyright (c) 2022 Bhutan Journal of Research and Development
This work is licensed under a Creative Commons Attribution 4.0 International License.
All articles published in BJRD are registered under Creative Commons Attribution 4.0 International License unless otherwise mentioned. BJRD allows unrestricted use of articles in any medium, reproduction and distribution by providing adequate credit to the authors and the source of publication.