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A brief introduction to the Nonlinear atmospheric Dynamics Research Group in the State Key Laboratory of lasg

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Progress in Natural Science:Materials International 2002年第3期 81-82页

作者： MU Mu and wang Jiafeng(institute of atmospheric {3., chinese academy of sciences, beijing 10002., China) institute of atmospheric physics Chinese Academy of SciencesBeijing 100029China

Nonlinear atmospheric dynamics is an interdisciplinary branch of atmospheric sciences, geophysical fluid dynamics and nonlinear sciences. As a basis for numerical weather prediction and short-term climate prediction, ... 详细信息

关键词： Ph A brief introduction to the Nonlinear atmospheric Dynamics Research Group in the State Key Laboratory of lasg

Experiments in numerical modelling of the Pacific sea surface temperature anomalies

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Acta Oceanologica Sinica 1992年第4期11卷 509-524页

作者： Zhang Ronghua and wang Wanqiu institute of atmospheric physics, Academia Sinica, beijing 100080, China institute of atmospheric physics Academia Sinica Beijing 100080 China China

By using the atmosphere-ocean coupled model (CGCM) which is composed of a 2-level global atmospheric general circulation model and a 4-layer Pacific oceanic general circulation model developed in the institute of atmospheric physics of chinese academy of sciences, and two model climatological fields got from the two independent models' numerical integrations respectively, the Pacific sea surface temperature anomalies (SSTA) from 1988 to 1989 are simulated in this paper with observed atmospheric general circulation data and sea surface temperature fields as initial conditions and monthly coupling scheme. In order to remove systematic biases of the model climatological fields, interaction variables between atmosphere and ocean are also corrected simultaneously. The experiments show that the simulation results can be improved effectively if these interaction variables are corrected in spite of the fact that there always exist systematic biases in independent numerical simulations of atmospheric part and oceanic part within CGCM. The basic characteristics of the observed Pacific SSTA in September and October 1988 have been simulated by using the correction scheme, such as the negative SSTA domain in the whole E-quatorial Pacific east to 150°E and the positive SSTA domain in the Western Pacific, the northern subtropical Pacific and nearly the whole Southern Pacific. Further numerical simulations show that the model can simulate not only the SSTA in the Pacific and its seasonal variations but also its interannual changes (for example, La Nino event in the Equatorial Pacific terminated after May 1989) to a certain degree. Furthermore, some problems existing in experiment processes and what we shoud do in the following stage are also discussed and analysed in this paper.

关键词： Experiments in numerical modelling of the Pacific sea surface temperature anomalies SSTA

A new method to prepare clean cuticular membrane from fossil leaves with thin and fragile cuticles

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Science China Earth sciences 2011年第2期54卷 223-227页

作者： wang Li1,2 & LENG Qin1,3.1 State Key Laboratory of Palaeobiology and Stratigraphy,Nanjing institute of Geology and Palaeontology,chinese {3. of sciences,Nanjing 210008,China 2 Graduate School of chinese academy of sciences,beijing 100049,China 3.Department of Science and Technology,Bryant University,Smithfield RI 02917,USA 1. State Key Laboratory of Palaeobiology and Stratigraphy Nanjing Institute of Geology and Palaeontology Chinese Academy of Sciences Nanjing 210008 China2. Graduate School of Chinese Academy of Sciences Beijing 100049 China3. Department of Science and Technology Bryant University Smithfield RI 02917 USA

Leaf cuticle analysis has long been a powerful tool for fossil plant identification, systematics, and palaeoclimatological recon- struction. In recent decades the application of stomatal frequency data that are relied on precise calculation of stomata on plant fossil cuticles to reconstruct ancient atmospheric CO2 concentration made the preparation of cuticular membrane with sufficient size a critical technique in palaeoclimatological research. However, for plants with originally thin and fragile cuticles, e.g., most deciduous plants, conventional techniques sometimes fail to obtain cuticular membranes with sufficient size, or sometimes unable to recover any. This has largely hampered the usage of fossil cuticle analysis in palaeobotanical and palaeo- climatological research. Here, we describe a new method using clear nail polish as a medium to ＂strengthen＂ the originally thin and fragile cuticles prior to maceration procedures. We demonstrate the method by using middle Eocene Metasequoia fossils that were notorious for the difficulty of recovering large-sized clean cuticular membranes due to their thin and fragile nature. Metasequoia, with well-documented and widely-distributed fossil records since the Late Cretaceous and with a living repre- sentative, 114. glyptostroboides, as a comparative reference, bas been widely used as a model genus for the study of evolution of plants, palaeoclimatological reconstruction, and plant adaptation to climate changes. But its deciduous habit produces thin cuticles and makes the preparation of clean cuticular membranes a tedious process. The new method successfully allows us to recover its delicate cuticular membranes with sufficient sizes for SEM observation and stomatal frequency analysis.

关键词： fossil leaf cuticle Metasequoia new method thin and fragile cuticle SEM observation stomatal frequency CO2

Effect of atmospheric aerosols on UV-B radiation reaching the ground

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Journal of Environmental sciences 1993年第2期5卷 224-229页

作者： wang Shaobin Su WeihanResearch Center for Eco-Environmental sciences, chinese academy of sciences, {3. 100085, China Research Center of Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 China. China

Solar ultraviolet radiation reaching the ground can be reduced due to light scattering of atmospheric aerosols. Aerosol pollution has led to the decrease in biological active UV-B radiation by about 45% and 10% in city and rural areas, respectively. In populated areas, effect of aerosol scattering on UV-B radiation may offset the increased amount of UV-B caused by ozone depletion, but in clean areas such as two poles, ozone depletion may have great damage effects on ecosystems.

关键词： atmospheric aerosol UV-B radiation ozone reduction.

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, {3. 100085, ChinaPeng Lixin and Tang XiaoyanResearch Center of Environmental sciences, Peking University, {3. 100871, China 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.

Biologically effective ultraviolet radiation in beijing area

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Journal of Environmental sciences 1993年第2期5卷 216-223页

作者： wang Shaobin Su WeihanResearch Center for Eco-Environmental sciences, chinese academy of sciences, {3. 100085, China Research Center for Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 China. China

Ozone layer depletion implies the enhancement of solar ultraviolet radiation at the earth's surface. However, aerosol contributes to the scattering of solar radiation and leads to the reduction of UV-B radiation on the ground. In this paper, the model calculation shows that due to effects of atmospheric ozone and aerosol UV-B radiation in beijing in the past decade has decreased with the annual change rate of 0.7%, which is probably approximate to the measured values. The effects of three scenarios for long-term changes in atmospheric ozone and aerosol concentrations on UV-B radiation reaching the ground in are also discussed.

关键词： UV-B biological efftent zone aerosol beijing.

THE SOLVABILITY FOR A CLASS OF SINGULARLY PERTURBED QUASI-LINEAR DIFFERENTIAL SYSTEM

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Acta Mathematica Scientia 2008年第3期28卷 495-500页

作者：莫嘉琪王辉林万涛 Department of Mathemtics Anhui Normal University Division of Computational Science E-Institutes of Shanghai Universities at SJTUShanghai 200240China Department of Mathematics Huzhou Teachers'CollegeHuzhou 313000China chinese academy of Meteorological sciences lasg Institute of Atmospheric PhysicsChinese Academy of Sciences

The solvability for a class of singularly perturbed Robin problem of quasilinear differential system is considered. Using the boundary layer corrective method the formal asymptotic solution is constructed. And using t... 详细信息

关键词： Solvability singular perturbation differential system boundary layer

Rainfall spectrum change in North China and its possible mechanism

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Progress in Natural Science:Materials International 2004年第7期 46-52页

作者： DAI Xingang 1,2*, wang Ping 3. ZHANG Peiqun 4 and CHOU Jifan 1(1. College of Resources and Environmental sciences, Lanzhou University, Lanzhou 73.000, China 2. State Key Laboratory lasg,{3., chinese academy of sciences, beijing 10002., China 3. College of physics, Peking University, beijing 100871, China 4. National Climate Center, beijing 100081, China) College of Resources and Environmental sciences，Lanzhou University，Lanzhou 73.000，China State Key Laboratory lasg，institute of atmospheric {3.，chinese academy of sciences，beijing 10002.，China College of physics，Peking University，beijing 100871，China National Climate Center，beijing 100081，China College of Resources and Environmental sciences，Lanzhou University，Lanzhou 73.000，China

The seasonal distribution of the rainfall in North China has changed greatly since 1977, with more rainfall in spring and less in July, August, and September (JAS). Wavelet analysis showed that the JAS rainfall underwent an abrupt spectrum change in the mid-1960s. Its interannual variability has declined while the interdecadal component has become the dominant mode, associated with the dry climate. Correlation analysis found that the JAS rainfall is negatively correlated with the departures of the 500 hPa geopotential height significantly over the northwest and southwest of China, and positively correlated with the summer monsoon over eastern China. Therefore, the interdecadal ascending of the air pressure in northwestern China and the monsoon decaying over East Asia in the past 20 years may be the two major causes of North China drought.

关键词： North China drought wavelet spectrum abruption monsoon geopotential height interdecadal change.

Relationship and its instability of ENSO--chinese variations in droughts and wet spells

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Science China Earth sciences 2007年第1期50卷 145-152页

作者： SU MingFeng1,2 & wang huijun1 1 Nansen-Zhu International Research Center, institute of atmospheric physics,{3., beijing 10002., China 2 Graduate University of{3., beijing 10003., China 1. Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Graduate University of chinese academy of sciences Beijing 100039 China

Monthly data of Self-Calibrated Palmer Drought Severity Index (PDSI) from 1951 to 2000 are calculated using historical precipitation and temperature data for chinese 160 stations. Temporal and spatial pat-terns of the first empirical orthogonal function (EOF) of the PDSI reveals a fairly linear trend resulting from trends in precipitation and surface temperature, which is similar to the linear PDSI trend during 1951―2000 calculated using all monthly data. The EOF analysis also reveals that the leading mode correlates significantly with ENSO events in time and space. The ENSO EOF shows that during the typical warm phase of ENSO, surface conditions are drier in most regions of China, especially North China, but wetter than normal in the southern regions of Changjiang River, and Northwest China. During the typical cold phase of ENSO, these anomalies reverse sign. From 1951 to 2000, there are large multi-year to decadal variations in droughts and wet spells over China, which are all closely related to strong El Nio events. In other words, when one strong El Nio event happens, there is a possible big variability in droughts and wet spells over China on the multi-year or decadal scale. Studies also sug-gest that during the last 2―3.decades climate changes over China, especially North China's drying and northwest China's wetting, are closely related to the shift in ENSO towards warmer events and global warming since the late 1970s. The instability of the relationship is also studied. It is revealed that there is a good correlation between ENSO and chinese variations in droughts and wet spells in the 3.8-year band, but the correlation between ENSO and chinese variations in droughts and wet spells is instable. Studies suggest that there are decadal changes in the correlation: the wavelet coherency between ENSO and chinese variations in droughts and wet spells is high during 1951―1962 and 1976―1991, but low during 1963.1975 and 1992―2000.

关键词： PDSI variations droughts and wet Spells ENSO instability.