Time Series Analysis of Fine Particulates Matter (PM2.5) in Chaoyang District of Beijing

Abstract

Air pollution in Beijing is becoming hard to ignore, however, there are no long-term studies examining the particle pollution such as PM 2.5 concentration. This study describes current and predicts future PM 2.5 pollution for a three-year period, 1st January 2010 to 31st December 2012, from the U.S. Embassy monitoring site in Chaoyang, Beijing. We calculated the 24-hour and annual PM2.5 concentrations under EPA method and using the Box-Jenkins method to build a SARIMA model (Seasonal Autoregressive Integrated Moving Average). The results showed the PM2.5 concentration decreased from 2010 to 2012. The 24-hour PM2.5 concentration was 294μg/m³, ranged from 265.2μg/m³ to 318.5μg/m³. And the annual PM2.5 concentration was 94.5μg/m³ which yearly range from 89.5μg/m³ to 99.0μg/m³ and the quarterly value from 73.1μg/m³ to 108.6μg/m³. The 24-hours and annual concentration is about 7 to 8 times higher than the US National Ambient Air Quality Standard (NAAQS). There is an urgent need for long-term studies to guide policy makers to improve the air quality in Beijing.