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机构地区:[1]北京大学医学部公共卫生学院流行病与卫生统计学系教育部流行病学重点实验室,100191
出 处:《中华预防医学杂志》2009年第6期517-521,共5页Chinese Journal of Preventive Medicine
基 金:北京市科技计划(Z0004028040191)
摘 要:目的分析奥运窄气质量保障措施对北京城市空气污染指数(air pollution index,API)的影响,预测奥运会后的持续效应。方法描述2004--2008年北京城市API的时间分布状况,对2008年API进行时间序列分析,采用自回归求和滑动平均模型(autoregressive integrated moving average model,ARIMA)法建立预测模型,预测2008年12月空气质量。结果2004--2008年月平均API以3、11月最高,分别为120±66、116±72;7、8月最低,分别为83±28、77±27。2004--2008年各年空气质量类别中“优”、“良”天数所占比例分别为9.56%(35/366)、54.37%(199/366),8.49%(31/365)、54.52%(199/365),7.12%(26/365)、58.90%(215/365),8.77%(32/365)、58.63%(214/365),16.67%(61/366)、58.20%(213/366),有逐年增加的趋势(χ^2趋势=11.397,P=0.001)。建立ARIMA(1,0,0)模型可以较好拟合API时间序列,奥运期间干预措施可使API下降37.1%,用模型预测北京市2008年12月月平均API为82。结论奥运会期间北京市空气质量提升明显,临时干预措施效果显著。奥运会后空气质量仍维持在较好水平。Objective To analyze the impact of the measures for securing quality air for the 2008 Beijing Olympic and Paralympics Games on air pollution index (API) in Beijing and forecast the aftereffects. Methods The time-distribution of API in Beijing from 2004 to 2008 was described. The time sequence analysis was used and the autoregressive integrated moving average model (ARIMA) was chosen to establish an API forecasting model to predict the API in December,2008. Results From 2004 to 2008 ,the average API in March( 120 ± 66 ) was the highest followed by November( 116 ± 72 ) and the average API in July (83 ±28 ) was the lowest followed by August (77±27 ). The proportion of "excellent" and '" good" days from 2004 to 2008 were 9. 56% (35/366), 54. 37% (199/366), 8.49% (31/365), 54. 52% (199/365), 7.12% ( 26/365 ), 58.90% ( 215/365 ), 8.77% ( 32/365 ), 58.63% ( 214/365 ), 16.67% ( 61/366 ), 58.20% (213/366) respectively, with an increasing trend year by year ( 2 = 11. 397, P = 0. 001 ). The model of ARIMA ( 1,0,0 ) fitted well; according to the prediction of the ARIMA (1,0,0) model, the decrease of API that attributed to interim measures during the Olympic Games was 37. 1% and the average API of December was 82. Conclusion The interim measures during the Olympic Games were effective on promoting air quality. After the Olympic Games, air quality would still remain good.
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