【作者】 赵胡笳；

【导师】 张小曳； 车慧正；

【作者基本信息】 中国气象科学研究院 ， 大气物理学与大气环境， 2014， 博士

【摘要】 利用中国东北城市地区沈阳、鞍山、本溪、抚顺四个站点CE318太阳光度计观测数据反演了大气气溶胶光学特性包括：大气气溶胶光学厚度、Angstrom波长指数、单次散射比、粒子体积谱分布、复折射指数实部及虚部等，分析了它们的季节变化及影响因素。四个地区气溶胶光学厚度最大值多出现在春夏季节，最小值多出现在秋季。Angstrom波长指数在四个地区都是秋冬季节高而在春季较低。根据反演得到的沈阳、鞍山、本溪、抚顺四个站点晴空条件下地面和大气层顶大气气溶胶的直接辐射强迫和直接辐射强迫效率，分析其分布情况及季节变化特征。本溪地区直接辐射强迫平均值在地面、大气层顶分别为：-222.90±76.61W/m2，-24.80±15.87W/m2，其平均值要高于其他三个地区，这说明该地区污染较严重，气溶胶对地面和大气层的冷却能力都比较强。首次对沈阳、鞍山、抚顺三个地区吸收性气溶胶光学厚度(AAOD)及吸收性Angstrom波长指数(AAE)的季节变化进行了反演分析，结果表明：三个地区吸收性气溶胶光学厚度在冬季和夏季较大，在春季较小。沈阳地区吸收性Angstrom波长指数年平均值小于1.00，鞍山地区吸收性Angstrom波长指数约为1.19，抚顺地区吸收性Angstrom波长指数约为1.33。吸收性Angstrom波长指数的变化范围说明影响这三个地区的气溶胶粒子分属于不同类型。结合水平能见度观测研究了其与大气气溶胶光学厚度、Angstrom波长指数、单次散射比、粒子体积谱分布、复折射指数等参数的相互关系，分析了低能见度情况下四个地区大气气溶胶的光学特性及直接辐射强迫效应的特征和变化趋势。结果发现：沈阳、鞍山、本溪、抚顺四个中国东北城市地区的气溶胶光学厚度、Angstrom波长指数随着能见度的增加而降低。当能见度较低时，鞍山地区气溶胶粒子的散射性要明显强于其他三个地区，单次散射比均大于0.90，而本溪地区气溶胶粒子的吸收性较强，单次散射比均小于0.85。四个地区晴空条件下地面大气气溶胶直接辐射强迫随着能见度的降低而增加，这说明污染大气中的气溶胶粒子对地面的冷却作用明显。主要结论如下：1.沈阳地区年平均500nm大气气溶胶光学厚度为：0.69±0.38；Angstrom波长指数为：0.88±0.26；440nm整体/细/粗粒子单次散射比分别为：0.84±0.06，0.86±0.06，0.77±0.06；440nm复折射指数为：1.47±0.028。沈阳地区晴空条件下年平均地面大气气溶胶的直接辐射强迫为约-136.52±80.50W/m2；年平均大气层顶大气气溶胶的直接辐射强迫为约-3.81±21.73W/m2；地面大气气溶胶的直接辐射强迫效率为约-267.77±86.38W/m2；大气层顶大气气溶胶的直接辐射强迫效率为约-7.83±38.89W/m2。沈阳地区440nm、670nm、870nm、1020nm吸收性大气气溶胶平均光学厚度分别为0.15±0.11，0.11±0.09，0.10±0.08，0.09±0.08，吸收性Angstrom波长指数为0.86±0.24。沈阳地区年平均能见度约为13.88±7.39km；能见度小于10km时440nm单次散射比为：0.82±0.06；气溶胶光学厚度为0.89±0.45；Angstrom波长指数为0.98±0.31；440nm复折射指数为1.46±0.030。2.鞍山地区年平均500nm大气气溶胶光学厚度为:0.65±0.33；Angstrom波长指数为：0.79±0.26；440nm整体/细/粗粒子单次散射比分别为：0.87±0.06，0.89±0.06，0.81±0.06；440nm复折射指数为：1.49±0.018。鞍山地区晴空条件下年平均地面大气气溶胶的直接辐射强迫为约-102.14±52.59W/m2；年平均大气层顶大气气溶胶的直接辐射强迫为约-25.37±20.99W/m2；地面大气气溶胶的直接辐射强迫效率为约-208.45±66.11W/m2；大气层顶大气气溶胶的直接辐射强迫效率为约-48.91±32.76W/m2。鞍山地区440nm、670nm、870nm、1020nm吸收性大气气溶胶平均光学厚度分别为：0.10±0.07，0.05±0.04，0.05±0.04，0.04±0.04；吸收性Angstrom波长指数为1.19±0.39。鞍山地区年平均能见度约为13.56±6.20km；能见度小于10km时440nm单次散射比为：0.88±0.05；气溶胶光学厚度为0.88±0.35；Angstrom波长指数为0.93±0.31；440nm复折射指数为1.46±0.016。3.本溪地区气溶胶光学厚度最大，而Angstrom波长指数明显小于沈阳、鞍山、抚顺三个地区，这说明影响本溪地区的气溶胶粒子的粒径较大。本溪地区年平均500nm大气气溶胶光学厚度为：0.82±0.34；Angstrom波长指数为：0.52±0.22；440nm整体/细/粗粒子单次散射比分别为：0.81±0.03，0.82±0.03，0.81±0.09；440nm复折射指数为：1.46±0.041。本溪地区晴空条件下年平均地面大气气溶胶的直接辐射强迫为约-222.90±76.61W/m2；年平均大气层顶大气气溶胶的直接辐射强迫为约-24.80±15.87W/m2；地面大气气溶胶的直接辐射强迫效率为约-337.65±102.43W/m2；大气层顶大气气溶胶的直接辐射强迫效率为约-40.59±22.84W/m2。本溪地区年平均能见度约为12.83±5.68km；能见度小于10km时440nm单次散射比为：0.80±0.08；气溶胶光学厚度为1.21±0.48；Angstrom波长指数为0.74±0.26；440nm复折射指数为：1.47±0.046。4.抚顺地区气溶胶光学厚度最小，年平均500nm大气气溶胶光学厚度为：0.45±0.27；Angstrom波长指数为：0.84±0.29；440nm整体/细/粗粒子单次散射比分别为：0.85±0.06，0.88±0.05，0.77±0.06；440nm复折射指数为：1.49±0.025。抚顺地区晴空条件下年平均地面大气气溶胶的直接辐射强迫为约-85.94±37.49W/m2；年平均大气层顶大气气溶胶的直接辐射强迫为约-13.28±16.19W/m2；地面大气气溶胶的直接辐射强迫效率为约-232.86±61.19W/m2；大气层顶大气气溶胶的直接辐射强迫效率为约-27.81±28.91W/m2。抚顺地区440nm、670nm、870nm、1020nm吸收性大气气溶胶平均光学厚度分别为：0.08±0.04，0.04±0.02，0.03±0.02，0.03±0.02，吸收性Angstrom波长指数为1.33±0.36。抚顺地区年平均能见度约为11.52±5.84km；能见度小于10km时440nm单次散射比为：0.84±0.05；气溶胶光学厚度为0.54±0.30；Angstrom波长指数为1.04±0.26；440nm复折射指数为1.48±0.026。5.鞍山地区气溶胶粗粒子和细粒子的散射性都比较大；本溪地区气溶胶粗粒子和细粒子的吸收性都比较大；沈阳、抚顺地区气溶胶粗粒子的吸收性比较强。气溶胶光学厚度对沈阳地区气溶胶粒子的吸收性影响并不明显，而在鞍山、本溪、抚顺三个地区，大气气溶胶粒子在气溶胶光学厚度较低时以吸收性为主，在气溶胶光学厚度较高时以散射性为主。6.四个地区气溶胶粒子谱分布特征均呈现出：夏季细模态粒子起主要作用，春季粗模态粒子起主要作用，而秋冬季节则受到两种模态气溶胶粒子的共同影响，粒子谱分布呈现了典型的城市特征。随着气溶胶光学厚度的增加，气溶胶细粒子体积也明显增加，这说明细粒子是影响该地区光学厚度的主要因素之一。7.四个地区晴空条件下地面大气气溶胶直接辐射强迫具有明显的季节变化特征，均呈现出夏季大、秋冬季节小的特点。四个地区晴空条件下大气层顶大气气溶胶的直接辐射强迫则呈现春季较大，冬季较小的变化趋势，其中沈阳和抚顺两个地区晴空条件下大气层顶大气气溶胶的直接辐射强迫在冬季出现了正值，这与东北地区因地表存在积雪导致地表反照率较高有关。8.沈阳、鞍山、抚顺三个地区吸收性Angstrom波长指数分别为0.86±0.24，1.19±0.39，1.33±0.36。吸收性Angstrom波长指数(AAE)的变化范围表明：沈阳地区的气溶胶粒子类型可能与具有沙尘和有机碳等粒子外部涂层的黑碳气溶胶有关。鞍山地区气溶胶粒子则可能包含了大量的黒碳气溶胶。影响抚顺地区大气消光性的气溶胶粒子则可能与生物质燃烧有关。更多还原

【Abstract】 Aerosol optical properties such as Aerosol Optical Depth (AOD), Angstromexponent (AE), Single Scattering Albedo (SSA), volume size distribution,refractive index real part and imaginary part are retrieved by using CE318dataover four urban and industrial areas in Northeast China, Shenyang, Anshan,Benxiand Fushun. Seasonal variations and influence factors of these parametersare analyzed. The relationship between AOD and AE are discussed at each site.The possible influence factors for these parameters are concluded. The maximumAOD appeared in spring and summer more than other seasons while the minimumAOD appeared in autumn. AE is lower in spring while higher in autumn andwinter.Aerosol direct radiative forcing (ADRF) and direct radiative forcingefficiency under clear sky condition at Top of Atmosphere (TOA) and surface arecalculated over the four sites. The seasonal variations and distribution of ADRFand the efficiency of ADRFare discussed at each site, respectively. Thedistribution of ADRF at TOA and surface against AOD are also discussed for foursites, respectively. Aerosol direct radiative forcing at surface and Top ofAtmosphere in Benxi are-222.90±76.61W/m2,-24.80±15.87W/m2，respectively.The annual averaged value is higher than the other three areas which indicate thatthe pollution of Benxi is most seriously, the cooling effect of aerosols to thesurface and Top of Atmosphere is stronger.The seasonal variations of Absorption AOD (AAOD) and AbsorptionAngstrom exponent (AAE) in Shenyang, Anshan and Fushun have been analyzedfor the first time. The results show that the AAOD is higher in winter and summerwhile lower in spring. The value of AAE in Shenyang is less than unity, while have higher values in Anshan (1.19) and Fushun (1.33). The results indicated thatthe AAE information can help to distinguish different type of aerosols in the threesites.The effects of Visibility imposed on Aerosol Optical Depth (AOD), Angstromexponent (AE), Single Scattering Albedo (SSA), volume size distribution,refractive index has been discussed over the four sites. Especially, we analyzed thecharacteristics and variations of aerosol optical parameters and direct radiationforcing properties under the lower visibility.The AOD and AE are decreased withthe increasing of visibility over the four sites. When the visibility is lower, theaerosol scattering properties in Anshan is significantly strongger than the otherthree regions, the value of Single Scattering Albedo is greater than0.90. Theaerosol absorption properties in Benxi is intensity with the value of SingleScattering Albedo smaller than0.85. Aerosol direct radiative forcing (ADRF)under clear sky condition at surface is increased with the decreasing visibility overthe four sites. The results indicate that the cooling effect of pollution atmosphereaerosols to the surface is obviously.The major conclusion including the follow points:1. The annual averaged aerosol optical depth at500nm in Shenyang is about0.69±0.38. Angstrom exponent is about0.88±0.26. The Single Scattering Albedo(SSAT/SSAF/SSAC) are about0.84±0.06，0.86±0.06，0.77±0.06, respectively. Therefractive index is1.47±0.028. The annual averaged aerosols direct radiativeforcing at surface under clear sky conditions is about-136.52±80.50W/m2. Theannual averaged ADRF at TOA is about-3.81±21.73W/m2. The efficiencies ofADRF at surface and TOA are about-267.77±86.38W/m2,-7.83±38.89W/m2,respectively. The annual averaged absorption aerosol optical depth at440nm,670nm，870nm，1020nm in Shenyang are about0.15±0.11，0.11±0.09，0.10±0.08,0.09±0.08，respectively. The absorption Angstrom exponent is about0.86±0.24.The annual averaged visibility is about13.88±7.39km.The SSAT is about0.82±0.06at440nm when visibility is lower than10km. The aerosol optical depthis about0.89±0.45. Angstrom exponent is about0.98±0.31. The refractive index is1.46±0.030.2. The annual averaged aerosol optical depth at500nm in Anshan is about0.65±0.33. Angstrom exponent is about0.79±0.26. The Single Scattering Albedo (SSAT/SSAF/SSAC) are about0.87±0.06，0.89±0.06，0.81±0.06, respectively. Therefractive index is1.49±0.018. The annual averaged aerosols directradiativeforcing at surface under clear sky conditions is about-102.14±52.59W/m2. Theannual averaged ADRF at TOA is about-25.37±20.99W/m2. The efficiencies ofADRF at surface and TOA are about-208.45±66.11W/m2,-48.91±32.76W/m2,respectively. The annual averaged absorption aerosol optical depth at440nm,670nm,870nm,1020nm in Anshan are about0.10±0.07,0.05±0.04,0.05±0.04,0.04±0.04, respectively. The absorption Angstrom exponent is about1.19±0.39.The annual averaged visibility is about13.56±6.20km.The SSAT is about0.88±0.05at440nm when visibility is lower than10km. The aerosol optical depthis about0.88±0.35. Angstrom exponent is about0.93±0.31. The refractive index is1.46±0.016.3. The aerosol optical depth in Benxi is largest in the four sites.Angstrom exponentis smaller than the other three sites which indicate that the size of aerosol particlesin Benxi is much larger. The annual averaged aerosol optical depth at500nm inBenxi is about0.82±0.34. Angstrom exponent is about0.52±0.22. The SingleScattering Albedo (SSAT/SSAF/SSAC) are about0.81±0.03，0.82±0.03，0.81±0.09, respectively. The refractive index is1.46±0.041. The annual averagedaerosols direct radiative forcing at surface under clear sky conditions is about-222.90±76.61W/m2. The annual averaged ADRF at TOA is about-24.80±15.87W/m2. The efficiencies of ADRF at surface and TOA are about-337.65±102.43W/m2,-40.59±22.84W/m2, respectively. The annual averagedvisibility is about12.83±5.68km.The SSAT is about0.80±0.08at440nm whenvisibility is lower than10km. The aerosol optical depth is about1.21±0.48.Angstrom exponent is about0.74±0.26. The refractive index is1.47±0.046.4. The aerosol optical depth in Fushun is the minimum in the four sites. Theannual averaged aerosol optical depth at500nm in Fushun is about0.45±0.27.Angstrom exponent is about0.84±0.29. The Single Scattering Albedo(SSAT/SSAF/SSAC)are about0.85±0.06，0.88±0.05，0.77±0.06，respectively. Therefractive index is1.49±0.025. The annual averaged aerosols directradiativeforcing at surface under clear sky conditions is about-85.94±37.49W/m2. Theannual averaged ADRF at TOA is about-13.28±16.19W/m2. The efficiencies ofADRF at surface and TOA are about-232.86±61.19W/m2,-27.81±28.91W/m2,respectively. The annual averaged absorption aerosol optical depth at440nm， 670nm，870nm，1020nm in Fushun are about0.08±0.04，0.04±0.02，0.03±0.02，0.03±0.02，respectively. The absorption Angstrom exponent is about1.33±0.36.The annual averaged visibility is about11.52±5.84km.The SSAT is about0.84±0.05at440nm when visibility is lower than10km. The aerosol optical depthis about0.54±0.30. Angstrom exponent is about1.04±0.26. The refractive index is1.48±0.026.5. Both coarse and fine particles have larger scattering properties in Anshan whilein Benxi, both coarse and fine particles have larger absorption properties. Thecoarse particles have strongger absorption ability in Shenyang and Fushun. Thereare not obvious effects of AOD on the aerosol absorption ability in Shenyang, butin Anshan, Benxi and Fushun, there is higher absorption ability under low AODand higher scattering ability under high AOD.6.Fine particles play a main role in summer particle distribution. In spring, thecoarse particles are dominant. There is a mixture effect of both fine and coarseparticles in autumn and winter which presented a typical city characteristic. WhenAOD is higher, the aerosol fine particle volume has been increased significantly.The results show that fine particles may be the important factors influencing theregional aerosol optical depth.7. The aerosols directradiative forcing (ADRF) at surface under clear skyconditions is higher in summer and lower in autumn and winter. Aerosol directradiative forcing at the top of atmosphere over the four sites is higher in spring andlower in winter. The positive direct radiative forcing at the top of atmosphereoccurred in winter at Shenyang and Fushun. The result may be due to the highsurface albedo because of the snow cover in the northeast China.8.The annual averaged values of Absorption Angstrom Exponent (AAE) inShenyang，Anshan，Fushun are about0.86±0.24，1.19±0.39，1.33±0.36respectively. The values of AAE show that aerosols in Shenyang may be resultfrom black carbon coated with either absorbing or nonabsorbing material. Aerosolparticles in Anshan may contain a large amount of black carbon. In Fushun area,the dominant aerosol prticles may be related to the biomass burning.更多还原