上海市近8年PM10污染指数变化的DFA分析

摘要

运用消除趋势波动分析法( DFA),分析了上海市近8年PM10污染指数序列数据,并进行了时间序列的长程相关性分析,有效消除了数据中的噪声和非平稳信息影响,得到了定量描述PM10污染指数的长期演变行为的参数,即标度指数α.根据标度指数α的变化特性,探讨了PM10污染指数的长程幂律相关及其存在的时间尺度等问题.结果表明,该方法是可行的,从2003年7月1日开始,上海市的PM10污染指数变化的总体趋势是降低的,说明近8年来,上海市PM10污染情况得到了改善.该研究结果对于认识上海市城市大气环境质量变化过程和科学制定环保决策具有重要意义.%The detrended fluctuation analysis (DFA) method is employed lor long-term correlational assessment on the pollution indexes of PM10 in Shanghai during recent 8 years,effectively eliminates the noise and the impact of non-smooth information in the data,obtains the parameter of long-term evolved behavior which quantitatively describes the pollution indexes of PM10 ,that is,the scaling index a. According to the scale of changes in the characteristics of the index,it discusses the pollution indexes of PM10 on the long-range power-law and the existence of the relevant time scales and other issues. As indicated by the results,the PM10 pollution in Shanghai during recent eight years gets improred.the overall trend of the pollution indexes of PM10 in Shanghai is descending since July 1,2003. The research results were of great significance to understanding the air quality changes and making scientific environmental protection decisions for Shanghai.