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Trend,seasonal and diurnal variations of atmospheric CO_2 in beijing

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chinese Science Bulletin 2002年第24期47卷 2050-2055页

作者： WANG Yuesi, WANG Changke, GUO Xueqing, LIU Guangren & HUANG Yaolapc, institute of atmospheric Physics,{3., beijing 100083. china Department of Chemistry, Capital Normal University, beijing 10003., china lapc Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Department of Chemistry Capital Normal University Beijing China

The concentration of atmospheric CO2 in beijing increased rapidly at a mean growth rate of 3.7%·a-1 from 1993.to 1995. After displaying a peak of (409.7±25.9) μmol·mol-1 in 1995, it decreased slowly. Both the almost stable anthropogenic CO2 source and increasing biotic CO2 sink contribute to the drop of CO2 concentration from 1995 to 2000. The seasonal variation of CO2 concentration exhibits a clear cycle with a maximum in winter, averaging (426.8± 20.6)μmol·mol-1, and a minimum in summer, averaging (3.9.1±6.1)μmol·mol-1. The seasonal variation of CO2 concentration is mainly controlled by phenology. The mean diurnal variation of atmospheric CO2 concentration for a year in beijing is highly clear: daily maximum CO2 concentration usually occurs at night, but daily minimum CO2 concentration does in the daytime, with a mean diurnal difference more than 3..7μmol·mol-1. It has been revealed that the interannual variations of atmospheric CO2 concentration in winter and autumn regulated the

关键词： atmospheric CO2 annual variation seasonal variation diurnal variation urban environment.

Determination of atmospheric concentrations of halocarbons in beijing area

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Journal of Environmental sciences 1993年第1期5卷 76-82页

作者： Wang ShaobinResearch Center for Eco-Environmental sciences, chinese academy of sciences, beijing 100085,{3.Peng Lixin and Tang XiaoyanResearch Center of Environmental sciences, Peking University, beijing 100871,{3. Research Center for Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 China. China

Gas chromatography with ambient temperature injection and frozen-trapped techniques was used to determine the atmospheric concentrations of halocarbons over beijing. Halogenated compounds such as CFC-11, CFC-12. CHCl_3. CCl_4, CH_3.Cl_3. CHCl =CCl_2, and CCl2=CCl2 were measured and their concentrations are 109±8, 23.±13. 47±22, 97±24, 88±29, 11±1 and 17±3.(pptv), respectively.

关键词： GC-ECD atmospheric halocarbons beijing.

Speciation of the elements and compositions on the surfaces of dust storm particles:The evidence for the coupling of iron with sulfur in aerosol during the long-range transport

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chinese Science Bulletin 2005年第8期50卷 738-744页

作者： ZHANG Xingying1,2, ZHUANG Guoshun1,2,3. CHEN Jianmin2 & XUE Huaxin2 1. Center for atmospheric Environment Study, Department of Chemistry, beijing Normal University, beijing 100875,{3. 2. Center for atmospheric Chemistry Study, Department of Environ- mental Science and Engineering, Fudan University, Shanghai 20043.,{3. 3. lapc/nzc, institute of atmospheric Physics, nzc/lapc, chinese academy of sciences, beijing 1.002.,{3. Center for atmospheric Environment Study Department of Chemistry Beijing Normal University Beijing 100875 China Center for atmospheric Chemistry Study Department of Environmental Science and Engineering Fudan University Shanghai 200433 China lapc/nzc Institute of Atmospheric Physics NZC/LAPC Chinese Academy of Sciences Beijing 100029 China

The speciation of the elements on the surface of the particles collected during dust storm and non-dust storm in beijing and Inner Mongolia was studied by XPS. The ma- jor species of iron on the surface were oxides, sulfate, silicate, FeOOH and minor part sorbed on SiO2/Al2O3. Sulfate is the dominant species of sulfur on the surface. SiO2 and Al2O3.are the main components of Si and Al on the surface respectively. One of the most important findings was that the Fe(II) (FeS and FeSO4) produced could account for up to 44.3. and 45.6% of the total Fe on the surface in the aerosol sample collected at that night and next day of the “peak” time of the dust storm occurring on March 20, 2002, while Fe2(SO4)3. one of the Fe(III) species on the surface decreased from 67.1% to 49.5% and 48.0% respectively. Both S and Fe en- riched on the surface of aerosol particles. Fe(II) accounted for 1.3.?5.3. of total Fe in bulk aerosol samples during dust storm. These results provided strong evidence to sup- port the hypothesis of the coupling between iron and sulfur in aerosols during the long-range transport, which would have important impact on the global biogeochemical cycle.

关键词：物种形成原理 XPS 大气悬浮物 Fe-S结合粒子集合

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,{3., beijing 1.002., china lapc Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

Aerosol samples for PM2.5 were collected in beijing for 3. 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.

On the parameterization scheme of gravity wave drag effect on the mean zonal flow of mesosphere

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chinese Science Bulletin 2003年第10期48卷 1020-1023页

作者： GAO Shouting & RAN Lingkun State Key Laboratory of Atmosphere Physics and Chemistry (lapc), institute of atmospheric Physics,{3., beijing 1.002., china State Key Laboratory of Atmosphere Physics and Chemistry (lapc) Institute of Atmospheric Physics Chinese Academy of Sciences China

Based on McFarlane抯 parameterization scheme of gravity wave drag, a refined gravity-wave-drag scheme is presented. Both the drag effect of the momentum flux and the dissipation effect of gravity wave breaking on the mean zonal flow are included in the refined parameterization scheme. The dissipation effect can be formulated with the gravity wave numbers and the mean quantities. The refined parameterization scheme may represent a complete drag effect of stationary gravity wave breaking on the mean zonal flow.

关键词：参数化法重力波阻纬向气流中间层大气动力学

The mechanism of the effects of the upwelling mean on the ENSO event mature phase locking

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Science china Earth sciences 2007年第8期50卷 1266-1272页

作者： YAN BangLiang CMSR, institute of atmospheric Physics, chinese academy of sciences,{3., china 1. CMSR Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

The mechanism of the effects of the upwelling mean on the ENSO event mature phase locking is ex-amined by using a mixed-mode model. The results show that the positive feedback process of the ef-fects of the seasonal variation of the upwelling mean on the Kelvin wave is the mechanism of the locking of the event mature phase to the end of the calendar year. The memory of the Rossby waves for the sign-shifting of the sea surface temperature anomaly from positive to negative 6 months before the cold peak time is the other mechanism of the locking of the La Nia event mature phase to the end of the calendar year. The results here are different from previous ones which suggest that the balance between cold and warm trends of sea surface temperature anomaly is the mechanism involved. The cold trend is caused by the upwelling Kelvin wave from upwelling Rossby wave reflected at the western boundary, excited by the westerly anomaly stress over the central Pacific and amplified by the seasonal variation of the coupled strength in its way propagating westward. The warm trend is caused by the Kelvin wave forced by the western wind stress over the middle and eastern equatorial Pacific. The cause of the differences is due to the opposite phase of the seasonal variation of the upwelling mean to that in the observation and an improper parameterization scheme for the effects of the seasonal varia-tion of the upwelling mean on the ENSO cycle in previous studies.

关键词： Kelvin wave Rossby wave interaction between atmosphere and sea positive feedback

2003.vs 2002: A large amplitude wintertime temperature anomaly reversion event and its anomalous atmospheric circulation

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chinese Science Bulletin 2003年第S2期48卷 1-4页

作者： WANG Huijun nzc/LASG, institute of Atmlspheric Physics, chinese academy of sciences,{3.. china chinese Acad Sci Inst Atmospher Phys NZC LASG Beijing 100029 Peoples R China

It is revealed that there happened a large am-plitude wintertime temperature anomaly reversion event(LTAR) in Northern Hemisphere high latitude regions andSouth Australia for the year 2003.versus 2002, with the mostnotable change in Eurasia, eastern North America, NorthPacific, and South Australia. The accompanying atmosphericgeneral circulation anomalies are analyzed and the dominantchanges in the circulation arc found out. The anomalouscyclonic eddies over the north Pacific and the anomalousanticyclonic eddies over North Europe that cooperate eachother are mostly linked with the event. Both anomalous eddysystems are connected with the remote teleconnection pat-terns respectively. The research also suggests the existence ofa cross-equator teleconnection pattern, namely, the NorthernPacific-Western Pacific-Australia teleconnection pattern(NPWPA). It is not only related to LTAR, but also associatedwith the temperature transition from cold episode to warmepisode in the year 2003.versus 2002 during Decem-ber-January-February.

关键词： wintertime temperature anomaly reversion event atmospheric general circulation. NPWPA.

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,{3. 2. Center for atmospheric Chemistry Study, Department of Environmental Science & Engineering, Fudan University, Shanghai 20043.,{3. 3. lapc/nzc, institute of atmospheric Physics, CAS, beijing 1.002.,{3. 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 3.%―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% （3.%―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.

Adjoint method for the optimum planning of industrial pollutant sources

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Science china Earth sciences 2005年第8期48卷 1270-1279页

作者： LIU Feng1,2, HU Fei2 & ZHU Jiang2 1. College of Environmental sciences, Peking University, beijing 100871, china 2. {3., institute of atmospheric Physics, chinese academy of sciences, beijing 1.002., china 1. College of Environmental sciences Peking University 100871 Beijing China 2. lapc Institute of Atmospheric Physics Chinese Academy of Sciences 100029 Beijing China

The optimum planning of industrial pollutant sources, which optimizes the economic object without violating environmental constraints, is an important and hard task to be conquered. In this paper, an adjoint method is developed to solve the problem. The penalty function is in-troduced to deal with the environmental inequality constraints, and Lagrange function is con-structed to derive the adjoint equation and the gradient of the object function. In this means, the gradient of the object function can be calculated by solving the adjoint equation, and the infor-mation from the gradient is used to make the object function descend and approach to an optimal solution after some iterations. A two-dimensional, simplified model is used for numerical experi-ments. The theoretical derivations are verified by the results of the experiments. Furthermore, the adjoint method is shown to be of excellent convergence and efficiency, which is adaptive to the fast development of air quality numerical models and super computers.

关键词： optimum planning, industrial pollutant sources, adjoint equation, penalty function, gradient.