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A study of the chemical composition and transport of marine aerosols over the ocean near china

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Acta Oceanologica Sinica 1991年第3期10卷 407-422页

作者： Zhang Ni, Zhou Mingyu, Lu Naiping, F. P. Parungo, Wen Yupu, Yang Shaojing, Yang Yinan and Chen Binru national Research center for Marine Environmental Forecasts, State Oceanic administration, beijing, chinanational Oceanic and Atmospheric administration, Environmental Research Laboratories, Air Resources Laboratory, Boulder,CO, U.S. A.Academy of meteorological Sciences, State meteorological administration, beijing, chinaInstitute of High Energy Physics, Academia Sinica, beijing, china national Research center for Marine Env. Forecasts State Oceanic Admin. Beijing China China

In this paper the authors cite the aerosol samples collected with a KA-200 Anderson cascade Impactor and a KB-120 sampler during the first cruise of the Kuroshio investigation operated by the People's Republic of china and Japan cooperative program, from July 23 to August 21, 1987. The concentration size distributions and composition of marine aerosols over the Kuroshio area are analyzed. Neutron activation analysis is used to determine the elemental composition of the aerosols. The authors also discuss some characteristics of marine aerosols relating to long-range transport of crustal and anthropogenic elements from the continent to the remote ocean. Analytical results indicate that elements Al, Fe, Sc and Sb over this area are obviously influenced by the continent of Asia, and the size distributions are changed after long-range transport. The concentration of large particles increase. The concentrations of the elements C1 and Na are closely related to ocean conditions; the source of the elements Cl and Na is mainly the ocean. Besides coal combustion, the ocean is also a very important source for the element Se. The amount of Se is related to the distribution of marine life.

关键词： Sb A study of the chemical composition and transport of marine aerosols over the ocean near china over

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Spatial character of the gaseous and particulate state compound correlation of urban atmospheric pollution in winter and summer

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Science china Earth Sciences 2005年第S2期48卷 64-79页

作者： XU Xiangde, SHI Xiaohui, XIE Lian, DING Guoan, MIAO Qiuju, MA Jianzhong & ZHENG Xiangdong State Key Laboratory of Severe weather, Chinese Academy of meteorological Sciences, beijing 100081, china Nanjing University of Information Science and Technology, Nanjing 210044, china Department of Marine, Earth and Atmospheric Sciences, North Carolina State University, Raleigh, NC27695-8208, USA national Climate center, china meteorological administration, beijing 100081, china State Key Laboratory of Severe weather Chinese Academy of Meteorological Sciences Beijing 100081 China State Key Laboratory of Severe weather Chinese Academy of Meteorological Sciences Beijing 100081 China Nanjing University of Information Science and Technology Nanjing 210044 China Department of Marine Earth and Atmospheric Sciences North Carolina State University Raleigh NC27695-8208 USA national Climate center China Meteorological Administration Beijing 100081 China

The spatial/temporal variation information of atmospheric dynamic-chemical processes at observation site points of the "canopy" boundary of beijing urban building ensemble and over urban area "surface", as well as the seasonal correlation structure of the gaseous and par-ticulate states of urban atmospheric pollution (UAP) and its seasonal conversion feature at observation points are investigated, using the comprehensive observation data of the beijing City Air Pollution Observation Experiment (BECAPEX) in winter and summer 2003 with a "point-surface" combined research approach. By using "one dimension spatial empirical orthogonal function (EOF)" principal component analysis (PCA) mode, the seasonal change of gaseous and particulate states of atmospheric aerosols and the association feature of pollutant species under the background of the complicated structure of urban boundary layer (UBL) are analyzed. The comprehensive analyses of the principal components of particle concentrations, gaseous pollutant species, and meteorological conditions reveal the seasonal changes of the complex constituent and structure features of the gaseous and particulate states of UAP to further trace the impact feature of urban aerosol pollution surface sources and the seasonal difference of the component structure of UAP. Research results suggest that in the temporal evolution of the gaseous and particulate states of winter/summer UAP, NOx, CO, and SO2 showed an "in-phase" evolution feature, however, O3 showed an "inverse-phase" relation with other species, all possessing distinctive dependent feature. On the whole, summer concentrations of gaseous pollutants CO, SO2, and NOx were obviously lower than winter ones, especially, the reduction in CO concentration was most distinctive, and ones in SO2 and NOx were next. However, the summer O3 concentration was more than twice winter one. Winter/summer differences in PM10 and PM2.5 particle concentrations were relatively not obvious, which ind

关键词： aerosol correlation structure principal component analysis.

Moment tensor analysis of the acoustic emission source in the rock damage process

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Progress in Natural Science:Materials International 2005年第7期15卷 609-613页

作者： YU Huaizhong, ZHU Qingyong, YIN Xiangchu and WANG Yucang ( State Key Laboratory of Earthquake Dynamics, Institute of Geology, china Earthquake administration, beijing 100029, china State Key Laboratory of Nonlinear Mechanics, Institute of Mechanics, Chinese Academy of Sciences, beijing 100080, china School of Mathematics and Computational Science, Zhongshan University, Guangzhou 510275, china center for Analysis and Prediction, china Seismological Bureau, beijing 100036, china Quakes, Department of Earth Science, University of Queensland, Brishbane, Austrialia) State Key Laboratory of Earthquake Dynamics Institute of Geology China Earthquake Administration Beijing 100029 China State Key Laboratory of Nonlinear Mechanics Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China School of Mathematics and Computational Science Zhongshan University Guangzhou 510275 China center for Analysis and Prediction China Seismological Bureau Beijing 100036 China Quakes Department of Earth Science University of Queensland Brishbane Australia

To further investigate the mechanism of acoustic emission (AE) in the rock fracture experiment, moment tensor analysis was carried out. The AE sources characterized by crack sizes, orientations and fracture modes, are represented by a time-dependent moment tensor. Since the waveforms recorded by AE monitors correlate to the moment tensors, we prefer to select the P wave amplitude from the full-space Green's function of homogeneous and isotropic materials to determine the six independent components of the moment tensor. The moment tensor analysis was used to investigate the AE sources recorded in the experiment, and three types of micro-cracks were found, which are tensile mode, shear mode and mixture of the tensile and shear mode. In addition, the motion of micro-cracks was decided by eigenvectors of moment tensor. Results indicate that the moment tensor analysis may be used as a measurement to reflect the damage evolution of rock specimen.

关键词： moment tensor acoustic emission rock fracture.

Impact of the ENSO-related Tropical Pacific SST Anomalies on the Precipitation in china

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Impact of the ENSO-related Tropical Pacific SST Anomalies on...

中国气象学会2004年年会

作者： Wu Tongwen~1 Wu guoxiong~2 (1 national Climate center, china meteorological administration, beijing 100081 2 LASG, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029)

＜正＞This paper describes an investigation of the seasonality and quasi-stationary feature of precipitation variation in china associated with the tropical Pacific sea surface temperature （SST）. The correlation analysis of precipitation anomalies with respect to an objective ENSO index shows that drought conditions prevail in northern china and excessive rains occur in southern china in seasons of the warm phase of ENSO, namely with positive SST anomalies in the equatorial eastern Pacific, and opposite anomalies of precipitation in the cold phase of ENSO. The ENSO-related precipitation variation in the Yangtze River Valley （central china） has some uncertainty.

关键词： Tropical Pacific SST anomalies/Precipitation in china/Influence

Change in Extreme Temperature Event Frequency over china's mainland during 1961-2008

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Change in Extreme Temperature Event Frequency over China's m...

强化科技基础推进气象现代化——第29届中国气象学会年会

作者： Yaqing Zhou 1,2 Guoyu Ren 2,1 Jinzhong meteorological Bureau of Shanxi Province,Jinzhong 030600,china 2 Laboratory for Climate Studies,national Climate center,china meteorological administration(CMA),beijing 100081,china

利用 526 个国家级气象站 1961～2008 年的日最高、最低气温资料,分析了中国大陆地区气温极端事件的变化规律。结果表明,中国大陆地区霜冻日数和结冰日数明显减少,结冰日数减少显著的区域集中在北方,霜冻日数则在整个中国区域都显著减少... 详细信息

利用 526 个国家级气象站 1961～2008 年的日最高、最低气温资料,分析了中国大陆地区气温极端事件的变化规律。结果表明,中国大陆地区霜冻日数和结冰日数明显减少,结冰日数减少显著的区域集中在北方,霜冻日数则在整个中国区域都显著减少,夏季日数和炎热夜数明显增多,增多显著的区域主要在长江中下游和西南地区南部。日最高(低)气温的极大(小)值整体都有上升趋势,最高(低)气温的极大值在北方上升较明显,而在长江中下游和西南地区有下降的趋势;最高(低)气温的极小值则在全国范围都呈明显上升,极端最低气温上升尤为显著。冷夜 (昼)日数普遍明显减少,48 年中减少趋势为 8.23 d.(10 yr)-1[3.26 d.(10 yr)-1];暖夜(昼)日数明显增加,增加趋势为 8.16 d.(10 yr)-1[5.22 d.(10 yr)-1]。冷夜(昼)日数减少主要发生在冬季,其次是春、秋季,而暖昼和暖夜日数增加最显著的季节分别出现在秋季和夏季。从转折时间上看,极端气温指数的冷指是从 20 世纪 80 年代中后期开始显著减少的,暖指显著增加的时间则推迟到 20 世纪 90 年代中期。华北区域的研究结果表明,对于和最低气温有关的极端指数而言,城市化有显著影响,它加剧了冷指数的减少和暖指数的增加,国家站极端指数趋势变化中有 4 成以上是城市化造成的。另外城市化对气温日较差的影响也十分显著,近 48 年中国家站气温日较差的趋势变化基本上都是由城市化造成的。城市化对极端气温指数的影响不容忽视。

关键词：极端气温指数最高气温最低气温气候变化中国大陆

Effect of non-spherical dust aerosol on its direct radiative forcing

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Effect of non-spherical dust aerosol on its direct radiative...

强化科技基础推进气象现代化——第29届中国气象学会年会

作者： Zhili Wang a,Hua Zhang b,Xianwen Jing a,b,Xiaodong Wei c a Chinese Academy of meteorological Sciences,beijing 100081,china b Laboratory for Climate Studies,national Climate center,china meteorological administration,beijing 100081,china c meteorological center,East china Bureau of Air Control,Shanghai 201702,china

The optical properties of spherical and non-spherical dust aerosols are calculated using the Lorenz-Mie theory and the combination of T-matrix method and an improved geometric optics *** resulting optical properties are then applied in an interactive system that coupled a general circulation model with an aerosol model to quantitatively analyze the effect of non-spherical dust aerosol on its direct radiative forcing(DRF).Our results show that the maximum difference in dust instantaneous radiative forcing(IRF) between spherical and non-spherical particles is 0.27 W m-2 at the top of the atmosphere(TOA) and appears over the Sahara Desert due to enhanced absorption of solar radiation by non-spherical *** global annual means of shortwave(longwave) IRFs due to spherical and non-spherical dust aerosols at the TOA for all sky are-0.62(0.074) W m-2 and-0.61(0.073) W m-2,respectively,and the corresponding values for clear sky are-1.16(0.092) W m-2 and-1.14(0.093) W m-2,which indicates that the non-spherical effect of dust has almost no effect on their global annual mean ***,non-spherical dust displays more evident influences than above on its atmospheric-and land-temperature adjusted radiative forcing(ARF) at the TOA over the Saharan Desert,West Asia,and northern china,with an approximate maximum increase of 3.0 and decrease of 0.5 W *** global annual means of shortwave(longwave) ARFs due to spherical and non-spherical dust aerosols are-0.55(0.052) W m-2 and-0.48(0.049) W m-2 at the TOA for all sky,respectively,and the corresponding values for clear sky are-1.07(0.066) W m-2 and-0.95(0.062) W *** ARFs of dust become much weaker than their corresponding *** absolute values of annual mean ARF for non-spherical dust are approximately 13%(11.2%) and 6%(6%) less than those of spherical dust for the shortwave and longwave for all sky(clear sky),*** results indicate that the non-spherical effect of dust can reduce their ARFs more obvio

关键词： Dust Spherical/Non-spherical Particles IRF ARF

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像元分解法提取积雪边界线

山地学报 2004年第1期22卷 110-115页

作者：延昊张国平中国气象局国家气象中心中国气象局国家气象中心北京　100081

利用NOAA16 AVHRR的多光谱数据进行像元分解提取积雪边界线。首先对遥感数据进行主成分分析,提取含99%信息量的前两个主分量,对其进行散点图分析,获取终元。进行多光谱混合像元分解,提取积雪盖度参数,并依据积雪盖度提取积雪边界线。同... 详细信息

利用NOAA16 AVHRR的多光谱数据进行像元分解提取积雪边界线。首先对遥感数据进行主成分分析,提取含99%信息量的前两个主分量,对其进行散点图分析,获取终元。进行多光谱混合像元分解,提取积雪盖度参数,并依据积雪盖度提取积雪边界线。同时比较了最大似然分类提取的积雪边界线,发现分类积雪边界线变化较大,而盖度积雪边界线比较稳定,主要原因是像元分解提取的积雪边界线物理意义明确。

关键词： NOAA-AVHRR 混合像元光谱线性混合模型最大似然分类

Subseasonal features of the Asian summer monsoon in the NCEP climate forecast system

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Acta Oceanologica Sinica 2008年第3期27卷 88-103页

作者： Song YANG WEN Min R Wayne HIGGINS NOAA＇s Climate Prediction center Camp Springs Maryland 20746 USA Chinese Academy of meteorological Sciences Beijing 100081 China

The operational climate forecast system （CFS） of the US national centers for Environmental Prediction provides climate predictions over the world, and CFS products are becoming an important source of information for regional climate predictions in many Asian countries where monsoon climate dominates. Recent studies have shown that, on monthly-to-seasonal time-scales, the CFS is highly skillful in simulating and predicting the variability of the Asian monsoon. The higher-frequency variability of the Asian summer monsoon in the CFS is analyzed, using output from a version with a spectral triangular truncation of 126 waves in horizontal and 64 sigma layers in vertical, focusing on synoptic, quasi-biweekly, and intraseasonal time-scales. The onset processes of different regional monsoon components were investigated within Asia. Although the CFS generally overestimates variability of monsoon on these time-scales, it successfully captures many major features of the variance patterns, especially for the synoptic timescale. The CFS also captures the timing of summer monsoon onsets over India and the Indo-china Peninsula. However, it encounters difficulties in simulating the onset of the South china Sea monsoon. The success and failure of the CFS in simulating the onset of monsoon precipitation can also be seen from the associated features of simulated atmospheric circulation processes. Overall, the CFS is capable of simulating the synoptic-to-intraseasonal variability of the Asian summer monsoon with skills. As for seasonal-tointerannual time-scales shown previously, the model is expected to possess a potential for skillful predictions of the high-frequency variability of the Asian monsoon.

关键词： Asian summer monsoon onset evolution synoptic-to-intraseasonal variability NCEP climate prediction system

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Assessment of Dust Aerosol Optical Depth and Shortwave Radiative Forcing over the Northwest Pacific Ocean in Spring Based on Satellite Observations

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Atmospheric and Oceanic Science Letters 2009年第4期 223-228页

作者： CHEN Lin 1,2,SHI Guang-Yu 1,ZHONG Ling-Zhi 3,and TAN Sai-Chun 1 1 State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics,Institute of Atmospheric Physics,Chinese Academy of Sciences,beijing 100029,china 2 Key laboratory of Radiometric Calibration and Validation for Environmental Satellites (KLRCV),national Satellite Meteorology center,china meteorological administration (NSMC/CMA),beijing,100081,china 3 State Key Laboratory of Severe weather,Chinese Academy of meteorological Sciences,beijing 100081,china State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical FluidDynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beo＇ing 100029 China Key laboratory of Radiometric Calibration and Validation for Environmental Satellites （KLRCV） National Satellite Meteorology center China Meteorological Administration （SMC/CMA） Beijing 100081 China State Key Laboratory of Severe weather Chinese Academy of Meteorological Sciences Beijing 100081 China

Dust aerosol optical depth (AOD) and its ac-companying shortwave radiative forcing (RF) are usually simulated by numerical ***,by using 9 months of Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol product data in combination with Clouds and the Earth’s Radiant Energy System Single Scanner Footprint (CERES/SSF) data,dust AOD and its shortwave RF were estimated over the cloud-free north-west (NW) Pacific Ocean in the springs of 2004,2005,and *** results showed that in this region,the mean dust AOD and its shortwave RF were 0.10 and 5.51 W m 2,*** order to validate the dust AOD de-rived by MODIS,results from the Goddard Global Ozone Chemistry Aerosol Radiation and Transport (GOCART) model were also used *** correlation coefficient between the monthly averaged dust AOD derived by MODIS measurements and the model simulation results was approximately *** the estimates of the dust AOD and its shortwave RF obtained in this study are based mainly on satellite data,they offer a good reference for numerical models.

关键词： dust aerosols optical depth shortwave radiative forcing northwest Pacific satellite measurements