Atmospheric extinction is impacted by the chemical composition of particles.To better understand the chemical composition of PM_(2.5)(particles with diameters of less than 2.5μm)and its relationship with extinction,o...Atmospheric extinction is impacted by the chemical composition of particles.To better understand the chemical composition of PM_(2.5)(particles with diameters of less than 2.5μm)and its relationship with extinction,one-month sampling campaigns were carried out in four different seasons from 2013 to 2014 in Jinan,China.The seasonal average concentrations of PM_(2.5)were 120.9(autumn),156.6(winter),102.5(spring),and 111.8μg/m^(3)(summer).The reconstructed PM_(2.5)chemical composition showed that sulfate,nitrate,chlorine salt,organic matter(OM),mineral dust,elemental carbon(EC)and others accounted for 25%,14%,2%,24%,22%,3%and 10%,respectively.The relationship between the chemical composition of PM_(2.5)and visibility was reconstructed by the IMPROVE method,and ammonium sulfate,ammonium nitrate,OM and EC dominated the visibility.Seven main sources were resolved for PM_(2.5),including secondary particles,coal combustion,biomass burning,industry,motor vehicle exhaust,soil dust and cooking,which accounted for 37%,21%,13%,13%,12%,3%and 1%,respectively.The contributions of different sources to visibility were similar to those to PM_(2.5).With increasing severity of air pollution,the contributions of secondary particles and coal combustion increased,while the contribution of motor vehicle exhaust decreased.The results showed that coal combustion and biomass burning were still the main sources of air pollution in Jinan.展开更多
基金supported by the National Key Research and Development Program of China[Grant number 2016YFC0202001]the Chinese Academy of Sciences Strategic Priority Research Program[Grant number XDA23020301]the National Natural Science Foundation of China[Grant number 41375036]。
文摘陆海风是由于海陆表面之间的比热容不同而导致的昼夜热量分布差异,从而在海岸附近引发的大气中尺度循环系统.本文利用多普勒风激光雷达Windcube100s首次对黄海西海岸的海陆风的循环结构进行了观测研究.在2018年8月31日至9月28日观测期间发现,海陆风发展高度一般在700 m至1300 m.海陆风转化持续的时间为6小时至8小时.在425m高度,海风水平风速出现最大值,平均为5.6 m s^(-1).陆风最大水平风速出现在370 m,约为4.5 ms^(-1).最大风切变指数在1300m处,为2.84;在陆风向海风转换过程中,最大风切变指数在700m处,为1.28.在同一高度上,风切变指数在海风盛行和陆风盛行时的差值范围为0.2-3.6,风切变能反映出海陆风的发展高度.
基金supported by the National Key Research and Development Program of China grant number 2016YFC0202001the Chinese Academy of Sciences Strategic Priority Research Program grant number XDA23020301+1 种基金the National Natural Science Foundation of China grant numbers 41375036 and 91644226the National Key Research and Development Program of China grant number2018YFC0214002。
基金supported by the National Key R&D Program of China(No.2017YFC0210000)the National Natural Science Foundation of China(Nos.41705113 and 41877312)+1 种基金the Young Talent Project of the Center for Excellence in Regional Atmospheric Environment CAS(CERAE201802)the Beijing Major Science and Technology Project(No.Z181100005418014)。
文摘Atmospheric extinction is impacted by the chemical composition of particles.To better understand the chemical composition of PM_(2.5)(particles with diameters of less than 2.5μm)and its relationship with extinction,one-month sampling campaigns were carried out in four different seasons from 2013 to 2014 in Jinan,China.The seasonal average concentrations of PM_(2.5)were 120.9(autumn),156.6(winter),102.5(spring),and 111.8μg/m^(3)(summer).The reconstructed PM_(2.5)chemical composition showed that sulfate,nitrate,chlorine salt,organic matter(OM),mineral dust,elemental carbon(EC)and others accounted for 25%,14%,2%,24%,22%,3%and 10%,respectively.The relationship between the chemical composition of PM_(2.5)and visibility was reconstructed by the IMPROVE method,and ammonium sulfate,ammonium nitrate,OM and EC dominated the visibility.Seven main sources were resolved for PM_(2.5),including secondary particles,coal combustion,biomass burning,industry,motor vehicle exhaust,soil dust and cooking,which accounted for 37%,21%,13%,13%,12%,3%and 1%,respectively.The contributions of different sources to visibility were similar to those to PM_(2.5).With increasing severity of air pollution,the contributions of secondary particles and coal combustion increased,while the contribution of motor vehicle exhaust decreased.The results showed that coal combustion and biomass burning were still the main sources of air pollution in Jinan.
