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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 Austrialia

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.

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

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

Dependence of magnetic field just inside the magnetopause on subsolar standoff distance:global MHD results

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Dependence of magnetic field just inside the magnetopause on...

第十四届全国日地空间物理学术研讨会

作者： Wang Ming1,2 Lu JianYong1,2 Liu ZiQian3 Pei ShiXin1 (1 College of Math & Physics, Nanjing University of Information Science & Technology, Nanjing 210044, china ) (2 national center for space weather, china Meteorology administration, beijing 100081, china ) (3 Chinese Academy of meteorological Science, Graduate University of Chinese Academy of Science, beijing 100081, china )

The subsolar magnetopause is the boundary of solar wind and the Earth’s magnetosphere where reduced solar wind dynamic pressure is equal to the magnetic pressure of the Earth’s outer magnetosphere. We use a global MHD model to estimate the ratio （f） of the compressed magnetic field just inside the subsolar magnetopause to the purely dipolar magnetic field. We also compared our numerical results with a similar work by Shue with the THEMIS data. Our results show that the ratio f is linearly proportional to the subsolar magnetopause standoff distance （r0） for both northward and southward interplanetary magnetic field, which in property is consistent with Shue’s result but the proportionality constant is smaller, although previous theoretical studies show that the ratio f is nearly independent of the subsolar standoff distance. The global model results also show that the ratio f is smaller for the southward IMF under the same r0 and the proportionality constant for the southward IMF is larger than that for the northward IMF. Both conclusions agree with statistical results from observations by Shue.

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The relationship between spatial extent and duration of severe droughts in china over the last 50 years

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The relationship between spatial extent and duration of seve...

2010 Second IITA International Conference on Geoscience and Remote Sensing (IITA-GRS 2010)

作者： ZHANG Da-quan College of Atmospheric Sciences Lanzhou University Lanzhou china 730000FENG Guo-lin Laboratory for Climate Studies national Climate center china meteorological administration beijing china 100081

Correlation between spatial extent and duration of severe droughts process and its statistical law is analyzed using Palmer Drought Severity Index （PDSI） through a newly developed system of drought process monitoring. Results indicate that during the period from late 1990s to early 2000s,the percentage of severe drought （PDSI＜-3.0） in china is unprecedented since 1960 under the background of global warming and the variation of the distributions of droughts coverage areas in different seasons is uneven. The distribution of spatial extent and durations of severe droughts follows a power-law,e.g. the spatial-temporal characteristics of severe droughts is independent to their scaling,namely,being scale free. In general the area of severe droughts is correlated closely with its duration,while the deviations of the linear fit from its correlation is also high.

关键词： drought duration distribution power-law

Is an unusual large enhancement of ionospheric electron density linked with the 2008 great Wenchuan earthquake?

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Is an unusual large enhancement of ionospheric electron dens...

中国科学院地质与地球物理研究所2008学术年会

作者： Biqiang Zhao,Min Wang,Tao Yu,Weixing Wan,Jiuhou Lei,Libo Liu, and Baiqi Ning 1 beijing national Observatory of space Environment,Institute of Geology and Geophysics,Chinese Academy of Sciences,beijing,china. 2 Institute of Earthquake Science,china Earthquake administration, beijing,china. 3 national center for space weather,china meteorological administration, beijing,china. 4 Department of Aerospace Engineering Sciences,University of Colorado, Boulder,Colorado,USA.

[1]On 12 May 2008 at 0628 UT a major earthquake M = 8.0 struck Wenchuan County (31.0°N,103.4°E) in southwest *** maximum ionospheric electron density at F peak(NF) recorded an unusual large enhancement during the afternoon-sunset sector by the Chinese ionosondes over Wuhan(30.5°N,114.4°E) and Xiamen(24.4°N,123.9°E), which are close to the earthquake *** averaged increase at these two stations is about 2 times on a geomagnetic quiet day,9 May(Kp≤2),3 days prior to the earthquake,relative to the median value of 1 -12 May,whereas the increase was much less significant over Yamagawa(31.2°N,130.6°E) and Okinawa(26.7°N,128.2°E) in *** the data from the network of 58 global positioning system receivers around china and the global ionospheric map,the variations of the total electron content reveal the region where enhancement persisted for a long period to be within longitudes 90°-130°*** results suggest that this abnormal enhancement is most possibly a seismo-ionospheric signature.

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DETECTING TROPICAL CYCLONE WATER VAPOR TRANSPORTATION WITH THE TRMM AND ADVANCED MICROWAVE SOUNDING UNIT(AMSU)

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DETECTING TROPICAL CYCLONE WATER VAPOR TRANSPORTATION WITH T...

作者： WangXin~1 FangXiang~(1,2) Qiu Hong~1 Zhu Yuanjing~2 1 national Satellite meteorological center of china meteorological administration, beijing,china,100081 2 Department of Atmospheric Science,School of Physics,Peking University, beijing,china,100871

The AMSU-B data contain the vertical distribution of the retrieved water vapor from satellite brightness temperature. The tropical cyclone Matsa event in 2005 formed from the northwest pacific is analysised by combining the AMSU-B water vapor fields with the latent *** show the combination the TRMM latent heating data in the heavy precipitation area around TC,we find heat release is one of the most important factors to impact TC intensity,especially to the long-life and land load *** there is a time delay between the low level water vapor convergence and the middle layer latent heat,which will improve the real-time forecast of tropical cyclones.

关键词： Index Terms—One two three four five