基于时间序列变化的PM_(2.5)质量浓度趋势分析

Trend analysis of PM_(2.5) based on the time series variation

PM2.5即直径小于2.5 um悬浮于空气中的可吸入颗粒物,被人体吸入后,可直达肺部干扰气体交换。文章利用PM2.5监测网每小时更新的实时数据为依据、实地考察所得的监测站地理环境、天气及其他影响因素,研究了以日、周、月为时间间隔的PM2.5质量浓度变化趋势。结果表明,PM2.5质量浓度变化趋势为冬高夏低、日变化较大、且年质量浓度呈现马鞍形双峰值趋势,是一个具有周期变化的非平稳时间序列。

The inhalable particulate matter whose diameter is under 2.5 μm and which is suspended in the air is called PM2.5.Once breathed in human body,it can reach the lungs directly and disturb the gas exchange.Based on the real time data from PM2.5monitoring network and the records of monitoring station＇s geographical conditions,weather conditions and other influence factors through field study,the paper researches the variation trend of PM2.5by the time interval of day / week / month and then gives a fitting model.The results shows that in winter the variation trend of PM2.5mass concentration is higher than that in summer and the diurnal variation is changed greatly.And the PM2.5mass concentration＇s year variation has two kurtosis,which is a nonstationary time series with periodic variation.