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                                  【来源:132彩票 | 发布日期:2019-05-10 】     【选择字号:


                                    主 人:黄宁  教授
                                    陈松蹊 ,国家特聘专家 ,北京大学讲席教授 ,北京大学统计科学中心联席主任。他是美国科学促进会会员,数理统计学会资深会员  ,美国统计学会会员 ,国际统计学会当选会员 ,国际数理统计学会 (IMS) 理事会常务理事 。同时担任The Annals of Statistics编委(2010-2018年) ,美国统计学会会刊编委(自2018年) ,Environmentrics编委(自2018年) 。自2015年他的团队在评估中国北方地区大气污染的变化  ,提出了去除气象干扰的方法 ,已经发布六份空气质量报告。目前主持国家重点研发专项项目“空气质量统计诊断模型”,两项自科基金重点项目  。
                                    There are speculations that the severe air pollution experienced in North China were the acts of climate change in general and a decreasing northerly wind in particular. We first conduct a retrospective analysis on 38 years (1979-2016) reanalyzed meteorological data from ERA-Interim, an archive of European
                                    Centre for Medium-Range Weather Forecasts (ECMWF) to quantify meteorological changes over the 38 years. Statistically significant changes have been detected in the surface temperature, relative humidity and boundary layer height in the region between the first and the second 19-year periods from 1979 to 2016. However, there was no significant reduction in the northerly wind within the mixing layer. We then build regression models of PM$_{2.5}$ on the meteorological variables using the 2015 and 2016 observations at 32 cities of the study region, which are used to quantify effects of the meteorological changes between the two 19-years periods on PM$_{2.5}$. It is found that the average meteorological changes led to 2% to 7% reduction in monthly PM$_{2.5}$ averages in most cities. Hence, the meteorological change may not be blamed for the air pollution situation in North China but the excessive emission from human activities should be.