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The formation process and cloud physical characteristics for a typical downburstproducing thunderstorm in beijing

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Chinese Science Bulletin 2003年第S2期48卷 77-82页

作者： GUO Xueliang FU Danhong Institute of Almospherie Physics, Chinese Academy of Sciences, beijing 100029. China Chinese Acad Sci Inst Atmospher Phys Beijing 100029 Peoples R China

The formation process and characteristics ofcloud physical structure of a severe thunderstorm accompa-nied with strong wind on 23 August, 2001 in beijing wasstudied using PSU/NCAR mesoscale model ( MM5) couplingwith a severe storm model with hail-bin microphysics. Theresults show that the specific topography and distributionfeatures of cold/warm current in the beijing region playedprominent roles in forming, developing and maintaining thesevere storm. Due to solar radiation heating and topographiclifting, the convective cells were easily formed when thewesterly airflow passed over high mountainous regions inbeijing. The warm and wet air entered the cloud from itsfrontage and enhanced the convection, and formed a largeamount of graupel/hail particles at the middle and upperportion of the clouds. The precipitation was primarilyformed due to melting of graupel/hail particles. The strongdowndraft was mainly produced by negative buoyancy dueto loading, melting of graupel/hail particles as well asevaporative cooling of rain water. The divergent airflow in-duced by the strong downdraft led to the disastrous burstwinds at the surface and also forced lifting of warm and wetairflow in the moving direction of the storm and formed newclouds that further promoted and maintained the storm de-velopment.

关键词： beijing region thunderstorm and disastrous wind cluud physical features.

Inorganic chemical composition and source signature of PM2.5 in beijing during ACE-Asia period

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Science Bulletin 2003年第10期48卷 1002-1005页

作者： ZHANG Renjian, XU Yongfu & HAN Zhiwei LAPC, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029, China LAPC Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Aerosol samples for PM2.5 were collected in beijing for 38 consecutive days from March to April 2001 using an IMPROVE Sampler. Concentrations of 20 elements in PM2.5 were determined using a PIXE method. Results show that the average mineral dust concentration of PM2.5 was 14.6 mg/m3 during the observation period. On the sand-dust event days of March 21 and April 10, dust PM2.5 mass concentrations were 62.4 and 54.1 mg/m3, respectively. These demonstrate that fine particle pollution by dust event in beijing was very severe. The enrichment factors of S and Cu reached minimums on the dusty days and were high on the non-dusty days. It is considered that enrichment factors of elements in PM2.5, which are associated with human activities, can probably provide an effective method to distinguish local sources from external sources of dust. Factor analysis on the chemical composition in PM2.5 shows that sources of crustal matters, anthropogenic emission, and oil combustion contributed to PM2.5 levels in air in the springtime of 2001 in beijing.

关键词： dust ACE-Asia PM2.5 chemical composition source apportionment.

LONGITUDINAL STREAM-PROFILES AS INDICATORS FOR GEOMETRIC SEGMENTATION OF THE LANGSHAN- HUANGBAISI FAULT ZONE, NORTHWEST beijing

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地震地质 1991年第4期 300-305+299页

作者： Cheng Shao-ping, Yang Gui-zhi and Yang Zhe(Institute of Geology, State Seismological Bureau, beijing 100029, China)

The Langshan-Huangbaisi fault zone in northwest beijing is the southwestern part of the normal fault zone on the northern margin of the Yanqing basin, 35.5km long and NNE-NEE-trending in general, on which two major 130°- 140° bends separate it into three segments with different *** the Hack’s method, 71 longitudinal stream-profiles along the fault zone are analysed, shawing a well geomorphic response to the fault geometry. On these two major bends the gradient indices,K values, are relatively high. These three segments greatly differ in K *** stream-profiles are good tectonic-geomorphic indicators for geometric Segmentation of normal faults and will prqvide insight into segmented kinematics and paleoseismology.

关键词： beijing Langshan-Huangbaisi fault zone Longitudinal stream-profile Geometric segmentatoin Gradient index

Trend and seasonal variations of atmospheric CH_4 in beijing

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Journal of Environmental Sciences 2000年第3期12卷 369-374页

作者： WANG Yue\|si, WANG Ming\|xing, LUO Dong\|mei, ZHENG Xun\|hua, ZHOU Li (Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029, China) 中科院大气物理所北京 1 0 0 0 2

The atmospheric CH\-4 in beijing is still increasing, even though its increasing rate has significantly decreased from 1.76%/a during 1985—1989 to 0.50%/a during 1990—1997. The seasonal variation of CH\-4 concentration showed a double\|peak pattern, one peak appearing in winter and the other in summer. It is evident that the annually seasonal variations of atmospheric CH\-4 in beijing are different. From 1986 to 1997, the atmospheric CH\-4 increased by 185 ppbv, 37% and 21% of which were due to the increase in winter and in summer, respectively. After 1993, the annually seasonal increasing rate of CH\-4 concentration in summer (due to emission from biogenic sources) is negative while the increasing rate in winter (due to emission from non\|biogenic sources) is positive about 25 ppbv/a. As a result, the increase of CH\-4 emission from non\|biogenic sources in winter is the major reason that caused the annually seasonal increasing rate from 1993 to 1997. The biogenic sources in beijing are shrinking while the non\|biogenic ones (such as fossil fuel combustion) are enlarging.

关键词： atmospheric CH\-4 increasing rate seasonal variation annually seasonal variation

Estimating possible impact of human activity on the warm season temperature in beijing since the industrial era

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Chinese Science Bulletin 2010年第16期55卷 1590-1593页

作者： QIN Li1,2 & ZHOU Xin1,2 1 Institute of Geology and Geophysics,Chinese Academy of Sciences,beijing 100029,China 2 Graduate University of Chinese Academy of Sciences,beijing 100049,China Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China Graduate University of Chinese Academy of Sciences Beijing China

Global surface temperature shows an increasing trend over the past 100 *** and natural factors have been invoked to explain this warming, but their relative contribution and the spatial variability remain *** on a 2650-year temperature record from a stalagmite near beijing, we explore the possible impacts of human activity on the warm season temperature in beijing since the industrial era using the method of singular spectrum analysis (SSA).The results suggest that the warm season temperature in beijing under the natural forcing should have an overall decreasing trend for the past 130 years (1870 to 2000 AD) with an amplitude of 0.45±0.84°C, while the instrumental record and stalagmite data show an increase of 1.08°*** imply that human activity would have caused an increase in the warm season temperature of beijing for about 1.53±0.84°C compared to its natural trends, from 1870 AD to 2000 *** results also suggest that anthropogenic forcing began to significantly influence the temperature since 1870 AD, and the effect further intensified since 1915 AD.

关键词：人类活动北京温度工业时代季节温暖估计地表气温

CLIMATIC BEHAVIOUR OF THE LAST DEGLACIATION RECORDED IN SWAMP SEDIMENTS NEAR beijing

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Scientia Geologica Sinica 1999年第1期 41-49页

作者： Lanying Wei( Institute of Geology. Chinese Academy of Sciences, beijing, 100029, China )Yanchou Lu Jinhui Yi( Institule of Geology, State Seismological Bureau, beijing, 100029, China)

Although the climatic events in relation with the North Atlantic Younger Dryas have been reported from a large number of terrestrial records in China and in the surrounding ocean, the climatic behaviour during the last deglaciation becomes increasingly a contentious point. Based on the palynological, carbon isotope, magnetic susceptibility and radiocarbon dating data from a swamp record near beijing, we demonstrate here that the last deglaciation experienced two warm-humid episodes （13,000- 12100,113,00- 10,95014C-years BP） and two severe episodes （12,100 to ~ 11,300 and10,950 to10,45014C-years BP）. Our results are therefore not entirely consistent with the changes in the North Atlantic region where two steps of deglaciation have been reported. The discrepancy might be related with the changes of the East Asian monsoon.

关键词： LDG Nature CLIMATIC BEHAVIOUR OF THE LAST DEGLACIATION RECORDED IN SWAMP SEDIMENTS NEAR beijing

Density Structure and Seismicity in beijing-Tianjin-Tangshan Area

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Earthquake Research in China 1994年第2期8卷 118-128页

作者： Yin Xiuhua,Liu Zhanpo and Liu TieshengInstitute of Geology,SSB,beijing 100029,China

By analyzing the gravity,magnetic,seismic and drilling data,the authors in this paper calculate and construct the density structure of the crust and upper mantle along the Haoding-Chengde and Zhangjiakou-Tanggu profiles and residual gravity anomalies in the *** compiled residual gravity anomalies g2 and g4 maps reflect qualitatively the spatial distribution of the density structure of the crustal "seismogenic layer" and the uppermost mantle layer at depth of 50-75 km in the *** order to reveal the relationship between density structure and seismicity,a great number of statistic calculations and comparisons of the available data and the results indicate that the seismicity in the crustal "seismogenic layer" is characterized by block movement:moderate-small earthquakes occurred generally within the blocks,moderate-strong earthquakes mostly along the borders of the blocks,strong earthquakes mostly at the edges and corners of the *** aftershocks of strong earthquakes tended to occur at

关键词： moderate gravity mantle crustal trending anomaly Tianjin mostly blocks corners

Local and non-local sources of airborne particulate pollution at beijing——The ratio of Mg/Al as an element tracer for estimating the contributions of mineral aerosols from outside beijing

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Science China Chemistry 2005年第3期48卷 253-264页

作者： HAN Lihui1, ZHUANG Guoshun1,2,3, SUN Yele1 & WANG Zifa3 1. The Center for Atmospheric Environmental Study, Department of Chemistry, beijing Normal University, beijing 100875, China 2. Center for Atmospheric Chemistry Study, Department of Environmental Science & Engineering, Fudan University, Shanghai 200433, China 3. LAPC/NZC, Institute of Atmospheric Physics, CAS, beijing 100029, China 1. The Center for Atmospheric Environmental Study Department of Chemistry Beijing Normal University 100875 Beijing China 2. Center for Atmospheric Chemistry Study Department of Environmental Science & Engineering Fudan University 200433 Shanghai China 3. Institute of Atmospheric Physics CAS LAPC/NZC 100029 Beijing China

A new element tracer technique has firstly been established to estimate the contri-butions of mineral aerosols from both inside and outside beijing. The ratio of Mg/Al in aerosol is a feasible element tracer to distinguish between the sources of inside and outside beijing. Mineral aerosol, inorganic pollution aerosol mainly as sulfate and nitrate, and organic aerosol are the major components of airborne particulates in beijing, of which mineral aerosol accounted for 32%―67% of total suspended particles （TSP）, 10%―70% of fine particles （PM2.5）, and as high as 74% and 90% of TSP and PM2.5, respectively, in dust storm. The sources from outside beijing contributed 62% （38%―86%） of the total mineral aerosols in TSP, 69% （52%―90%） in PM10, and 76% （59%―93%） in PM2.5 in spring, and 69% （52%―83%）, 79% （52%―93%）, and 45% （7%―79%） in TSP, PM10, and PM2.5, respectively, in winter, while only20% in summer and autumn. The sources from outside beijing contributed as high as 97% during dust storm and were the dominant source of airborne particulates in beijing. The contributions from outside Bei-jing in spring and winter are higher than those in summer, indicating clearly that it was related to the various meteorological factors.

关键词： mineral aerosol local sources non-local sources dust storm re-suspended dust element tracer technique.

Impact of climate change on dynamic of plant communities, lakes and swamps in beijing area during Holocene period

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Journal of Geographical Sciences 1999年第2期9卷 116-122页

作者： Zhang jia-hua Kong Zhao-chen Fu Cong-bin (START, Institute of Atmospheric Physics, Chinese Academy of Sciences, beijing 100029,China. Institute of Botany, Chinese Academy of Sciences, beijing 100093, China)

From 400-60 cm 26 samples were obtained in an 820 cm profile at Dongganchi of Fangshan in beijing. They provided a continuous record of vegetation and environmental changes over ca .7000 aB.P., as inferred from Spore-pollen. loss-on-ignition (LOI), and charcoal analysis,impacts of natural fire and human activities on plant communities and lakes and swamps were considered. 1) From 7000-5960 aB.P, the forest development was limited, probably in response to climate Warming. Aquatic and marsh plants began to increase, bat the lakes and swamps in some areas were limited. 2) About 5960-3390 aB.p, presumably in responded to climate warming which was warmer than that at present Aquatic plants began to become abundant,reflected the widespread development of the lakes and swamps, the climate was wet with annual precipitation higher than that at present 3) About 3390-1000 aB.P, human activities have kept to be the dominating factor in the evolution of vegetation and climatic change. Temperature decreased, and the annual precipitation rapidly reduced in Baijing area. the lakes and swamps gradually shrank back, some of them even disappeared. 4) After 1000 aB.P, there was a severe fluntuction, and early during this time, it was comparatively warm and humid, but became cool and dry later. In the meantime. human activities were intensified. agricultural activity was flourished. and large area of water field was cultivated

关键词： plant communities. lakes and swamps, pollen analysis, Holocene. Dongganchi profile beijing