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Simulation of the future change of East Asian monsoon climate using the IPCC SRES A2 and B2 scenarios

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chinese science Bulletin 2003年第10期48卷 1024-1030页

作者： BUEH Cholaw LASG, Institute of Atmospheric physics, chinese academy of sciences, beijing 100029, china LASG Institute of Atmospheric Physics Chinese Academy of Sciences China

In this paper, we applied the newest emission scenarios of the sulfur and greenhouse gases, i.e. Intergovernmental Panel on Climate Change (IPCC) Special Report on Emission Scenarios (SRES) A2 and B2 scenarios, to investigating the change of the East Asian climate in the last three decades of the 21st century with an atmosphere-ocean coupled general circulation model. The global warming enlarges the land-sea thermal contrast and, hence, enhances (reduces) the East Asian summer (winter) monsoon circulation. The precipitation from the Yangtze and Huaihe river valley to North china increases significantly. In particular, the strong rainfall increase over North china implies that the East Asian rainy area would expand northward. In addition, from the southeastern coastal area to North china, the rainfall would increase significantly in September, implying that the rainy period of the East Asian monsoon would be prolonged about one month. In July, August and September, the interannual variability of the precipitation enhances evidently over North china, meaning a risk of flooding in the future.

关键词：模拟亚洲东方季风气侯变化大气循环模型

Charmed Baryon in Diquark Model

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原子核物理评论 2009年第S1期26卷 190-193页

作者： WANG Qing-wu1,3, ZHANG Peng-ming1,2(1 Institute of Modern physics, chinese academy of sciences, Lanzhou 730000, china 2 center of theoretical Nuclear physics, National Laboratory of Heavy Ion Research Facility in Lanzhou,Lanzhou 730000, china 3 Graduate School of chinese academy of sciences, beijing 100049, china) Institute of Modern physics Chinese Academy of SciencesLanzhou 730000China Graduate School of chinese academy of sciences Beijing 100049China Institute of Modern physics Chinese Academy of SciencesLanzhou 730000China center of theoretical Nuclear physics National Laboratory of Heavy Ion Research Facility in LanzhouLanzhou 730000China

A diquark model is used to investigate single-charmed baryons. In this model,baryon is composed of two diquarks and an antiquark. Masses of lowest lying states with JP=1/2± are obtained. Baryons in our results are as heavy as other theoretic predictions and we suggest that the five-quark components should be considered in any three-quark model for studying the charmed baryons.

关键词： charm diquark pentaquark

TIME-IGGCAS model validation:Comparisons with empirical models and observations

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science china Technological sciences 2008年第3期51卷 308-322页

作者： YUE XinAn1,2,3, WAN WeiXing1, LIU LiBo1, NING BaiQi1, ZHAO BiQiang1 & ZHANG ManLian1 1 Institute of Geology and Geophysics, chinese academy of sciences, beijing 100029, china 2 Wuhan Institute of physics and Mathematics, chinese academy of sciences, Wuhan 430071, china 3 Graduate University, chinese academy of sciences, beijing 100049, china Institute of Geology and Geophysics Chinese Academy of Sciences

The TIME-IGGCAS (theoretical Ionospheric Model of the Earth in Institute of Ge- ology and Geophysics, chinese academy of sciences) has been developed re- cently on the basis of previous works. To test its validity, we have made compari- sons of model results with other typical empirical ionospheric models (IRI, NeQuick-ITUR, and TItheridge temperature models) and multi-observations (GPS, Ionosondes, Topex, DMSP, FORMOSAT, and CHAMP) in this paper. Several conclu- sions are obtained from our comparisons. The modeled electron density and elec- tron and ion temperatures are quantitatively in good agreement with those of em- pirical models and observations. TIME-IGGCAS can model the electron density variations versus several factors such as local time, latitude, and season very well and can reproduce most anomalistic features of ionosphere including equatorial anomaly, winter anomaly, and semiannual anomaly. These results imply a good base for the development of ionospheric data assimilation model in the future. TIME-IGGCAS underestimates electron temperature and overestimates ion tem- perature in comparison with either empirical models or observations. The model results have relatively large deviations near sunrise time and sunset time and at the low altitudes. These results give us a reference to improve the model and enhance its performance in the future.

关键词： ionosphere theoretical model empirical model satellite observation relative deviation

Control of atmospheric CO_2 concentrations by 2050: A calculation on the emission rights of different countries

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science china Earth sciences 2009年第10期52卷 1447-1469页

作者： DING ZhongLi1, DUAN XiaoNan2, GE QuanSheng3 & ZHANG ZhiQiang4 1 Institute of Geology and Geophysics, chinese academy of sciences, beijing 100029, china 2 The General Office of chinese academy of sciences, beijing 100864, china 3 Institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, beijing 100101, china 4 The Lanzhou Branch of the National science Library, the Scientific Information center for Resources and Environment, Lanzhou 730000, china Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China The General Office of chinese academy of sciences Beijing China Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China The Lanzhou Branch of the National science Library the Scientific Information Center for Resources and Environment Lanzhou China

This paper is to provide quantitative data on some critical issues in anticipation of the forthcoming international negotiations in Denmark on the control of atmospheric CO2 concentrations. Instead of letting only a small number of countries dominate a few controversial dialogues about emissions reductions, a comprehensive global system must be established based on emissions allowances for different countries, to realize the long-term goal of controlling global atmospheric CO2 concentrations. That a system rooted in "cumulative emissions per capita," the best conception of the "common but differentiated responsibilities" principle affirmed by the Kyoto Protocol according to fundamental standards of fairness and justice, was demonstrated. Based on calculations of various countries' cumulative emissions per capita, estimates of their cumulative emissions from 1900 to 2005, and their annual emissions allowances into the future (2006―2050), a 470 ppmv atmospheric CO2 concentration target was set. According to the following four objective indicators―total emissions allowance from 1900 to 2050, actual emissions from 1900 to 2005, emissions levels in 2005, and the average growth rate of emissions from 1996 to 2005―all countries and regions whose population was more than 300000 in 2005 were divided into four main groups: countries with emissions deficits, countries and regions needing to reduce their gross emissions, countries and regions needing to reduce their emissions growth rates, and countries that can maintain the current emissions growth rates. Based on this proposal, most G8 countries by 2005 had already expended their 2050 emissions allowances. The accu-mulated financial value based on emissions has reached more than 5.5 trillion US dollars (20 dollars per ton of CO2). Even if these countries could achieve their ambitious emissions reduction targets in the future, their per capita emissions from 2006 to 2050 would still be much higher than those of developing coun

关键词： international negotiations on climate change cumulative emissions per capita emission allowance

A mixed method for measuring low-frequency acoustic properties of macromolecular materials

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science china(physics,Mechanics & Astronomy) 2006年第6期49卷 729-739页

作者： LIU Hongwei1,YAO Lei1,3,ZHAO Hong1,3,ZHANG Jichuan2,3 & XUE Zhaohong2 1. National Key Laboratory of Acoustics,Institute of Acoustics,chinese academy of sciences,beijing 100080,china 2. Institute of Chemistry,chinese academy of sciences,beijing 100080,china 3. Graduate University of chinese academy of sciences,beijing 100049,china National Key Laboratory of Acoustics Institute of Acoustics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China Institute of Chemistry Chinese Academy of Sciences Beijing China

A mixed method for measuring low-frequency acoustic properties of macro-molecular materials is presented. The dynamic mechanical parameters of materials are first measured by using Dynamic Mechanical Thermal Apparatus(DMTA) at low frequen-cies,usually less than 100 Hz; then based on the Principles of Time-Temperature Super-position (TTS),these parameters are extended to the frequency range that acousticians are concerned about,usually from hundreds to thousands of hertz; finally the extended dynamic mechanical parameters are transformed into acoustic parameters with the help of acoustic measurement and inverse analysis. To test the feasibility and accuracy,we measure a kind of rubber sample in DMTA and acquire the basic acoustic parameters of the sample by using this method. While applying the basic parameters to calculating characteristics of the sample in acoustic pipe,a reasonable agreement of sound absorp-tion coefficients is obtained between the calculations and measurements in the acoustic pipe.

关键词： low-frequency acoustic properties,dynamic mechanical properties,Principles of Time-Temperature Superposition,acoustic pipe,sound absorption coefficient.

Simulation of freezing and melting of soil on the northeast Tibetan Plateau

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chinese science Bulletin 2011年第20期56卷 2145-2155页

作者： XIA Kun 1,2,3,LUO Yong 2,4,5 & LI WeiPing 2 1 Institute of Atmospheric physics,chinese academy of sciences,beijing 100029,china 2National Climate center,china Meteorological Administration,beijing 100081,china 3Graduate University of chinese academy of sciences,beijing 100049,china 4 center for Earth System science,Tsinghua University,beijing 100084,china 5Key Laboratory of Earth System Numerical Simulation,Ministry of Education,beijing 100084,china Institute of Atmospheric physics Chinese Academy of Sciences National Climate center China Meteorological Administration Graduate University of chinese academy of sciences center for Earth System science Tsinghua University Key Laboratory of Earth

Using observational data spanning the period from February to December 2009 and recorded at the Suli station in Qinghai Province,the land-surface model CLM3.0 was employed to simulate the freezing and melting of *** results indicate that the simulated soil temperature is higher than the observed soil temperature and the ultimate thawing date is earlier than the observed date during the melting *** the freezing period,the simulated soil temperature is lower than the observed soil temperature and the ultimate freezing of the deep soil is earlier than that ***,the simulation of freezing is better than that of melting,and the simulation of a shallow layer is better than that of a deeper *** the original CLM3.0,it is assumed that frozen soil begins to melt when the soil temperature exceeds 0C,which is inconsistent with *** critical freeze-thaw temperature was calculated according to thermodynamics equations and the freeze-thaw condition was *** this work,the melting rate for frozen soil was reduced using the modified scheme,and the simulated soil temperature was lowered. Meanwhile,the refreezing of soil during the melting season was well simulated and more closely matched ***,it was found that the rates of melting and freezing differ,with the former being slower than the latter,but refreezing during the melting season is rather quick.

关键词：土壤温度冻结期青藏高原东北部模拟融化观测数据热力学方程表面模型

Evolution of desertification in a two-dimensional energy balance model coupled with thermodynamics and dynamics

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science china Earth sciences 2010年第11期53卷 1726-1733页

作者： CHAO JiPing1,2 & LI YaoKun3,4 1National Marine Environmental Forecasting center, beijing 100081, china 2First Institute of Oceanography, State Oceanic Administration, Qingdao 266061, china 3State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics, Institute of Atmospheric physics, chinese academy of sciences, beijing 100029, china 4Graduate University of chinese academy of sciences, beijing 100049, china National Marine Environmental Forecasting center Beijing China First Institute of Oceanography State Oceanic Administration Qingdao China State Key Laboratory of Numerical Modeling for Atmospheric sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Graduate University of chinese academy of sciences Beijing China

The relationship between desert evolution and change in albedo has been investigated quasi-analytically using a zonal mean two-dimensional energy balance model which considers the radiation transmission process due to thermodynamics and bound- ary layer movement caused by kinetics. A climate state including temperature, zonal wind, meridional wind and vertical wind can be simulated according to the current zonal distribution of albedo. Given desert distribution, characterized by the value and distribution of albedo, the response of climate on albedo has been studied to analyze the evolution of desert climate. One significant result is that the simple model can reproduce mean meridional circulation. Another result indicates that climate corresponds to two equilibria. This happens when the junction temperature between vegetation and desert is higher than a certain critical value. As for the first equilibrium, the desert belt is predicted to move southward in the northern hemisphere with the increasing values of albedo, which corresponds to the current trend of climate change. For the second equilibrium, vegetation will expand northward with increasing values of albedo, which would indicate a narrowing of the desert belt. In order to determine if the two equilibria exist, new physical models are needed.

关键词： two-dimensional energy balance model desertification two equilibria

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Pesticide pollution

Journal of Environmental sciences 1991年第3期3卷 31-47页

作者： Shen Baocheng (Bozen Sun) and Shen QiResearch center for Eco-Environmental sciences,chinese academy of sciences,beijing 100083,chinaResearch center for science of sciences,City Commission of science and Technology,beijing,china

This is the first half of a review article, which deals with merits and demerits in many aspects of using pesticides, particularly in china for years. The second half published elsewhere continues to discuss about Treatment of Pesticide Wastewater, Special Mention of BHC and DDT, a Case Study of Metropolitan beijing, and Regula-tions, Standards promulgated lately. This is a review of its kind in English for a time, complete and comprehensive, that a glimpse of it will let you understand the past, present and future of the pesticide pollution situation and measures taken in this country.

关键词： pesticide pollution environment.

Impacts of the Wenchuan Earthquake on the Giant Panda Nature Reserves in china

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Journal of Mountain science 2010年第2期7卷 197-206页

作者： DENG Xiangzheng JIANG Qunou GE Quansheng YANG LinSheng Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China center for chinese Agricultural Policy Chinese Academy of Sciences Beijing 100101 China Graduate University of the chineseacademy of sciences Beijing 100049 China

The Wenchuan Earthquake that occurred in May of 2008 caused damages to large areas of Sichuan,Gansu,and Shaanxi provinces in *** from local governments and related management agencies show that the giant panda nature reserves in the earthquake-hit areas were heavily *** estimates in this paper of the impacts of the earthquake on the giant panda in the earthquake-hit areas were made based on the interpretation of remote sensing images and information collected by field survey.A rapid assessment method was designed to estimate the damages of the earthquake on giant panda *** using visual interpretation methods,we decoded the remote sensing images of the disaster area in the 49 giant panda nature *** results showed that the Wenchuan Earthquake and the succeeding secondary geological disasters caused great damages to the giant panda nature reserves and disturbed the normal life of the giant pandas there (e.g.,landscape fragmentation increased significantly).Undoubtedly,the life of the giant pandas there was ***,although the earthquake caused certain impacts on the giant pandas,it did not really threat their *** so,we still strongly advocate for protection of the giant pandas,and have prioritized a couple of measures to be taken to restore the giant panda nature reserves in the earthquake-hit areas.

关键词： Wenchuan earthquake Remote sensing Giant panda Giant panda nature reserve Rapid assessment method