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Arabian Peninsula-North Pacific Oscillation and its association with the Asian summer monsoon

Science china Earth sciences 2008年第7期51卷 1001-1012页

作者： SUN JianQi1, YUAN Wei2 & GAO YuZhong3 1 Nansen-Zhu International Research Centre, Institute of Atmospheric Physics, chinese academy of sciences, beijing 100029, china 2 china meteorological Administration Training Centre, beijing 100081, china 3 Heilongjiang meteorological Observatory, Harbin 150030, china 1. Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. china meteorological Administration Training Centre Beijing 100081 China 3. Heilongjiang meteorological Observatory Harbin 150030 China

Using correlation and EOF analyses on sea level pressure from 57-year NCEP-NCAR reanalysis data, the Arabian Peninsula-North Pacific Oscillation (APNPO) is identified. The APNPO reflects the co-variability between the North Pacific high and South Asian summer monsoon low. This teleconnec- tion pattern is closely related to the Asian summer monsoon. On interannual timescale, it co-varies with both the East Asian summer monsoon (EASM) and South Asian summer monsoon (SASM); on decadal timescale, it co-varies with the EASM: both exhibit two abrupt climate changes in the middle 1960s and the late 1970s respectively. The possible physical process for the connections between the APNPO and Asian summer monsoon is then explored by analyzing the APNPO-related atmospheric circulations. The results show that with a strong APNPO, the Somali Jet, SASM flow, EASM flow, and South Asian high are all enhanced, and an anomalous anticyclone is produced at the upper level over northeast china via a zonal wave train. Meanwhile, the moisture transportation to the Asian monsoon regions is also strengthened in a strong APNPO year, leading to a strong moisture convergence over India and northern china. All these changes of circulations and moisture conditions finally result in an anoma- lous Asian summer monsoon and monsoon rainfall over India and northern china. In addition, the APNPO has a good persistence from spring to summer. The spring APNPO is also significantly corre- lated with Asian summer monsoon variability. The spring APNPO might therefore provide valuable in- formation for the prediction of Asian summer monsoon.

关键词： Arabian Peninsula-North Pacific Oscillation East Asian summer monsoon South Asian summer monsoon wave train abrupt climate change

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The possible pivotal role of the eastward dust transport from Central Asia in the global temperature decrease

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chinese Science Bulletin 2006年第A01期51卷 1-7页

作者： LIU Mingzhe & WEI Wenshou Xinjiang Institute of Ecology and Geography, chinese academy of sciences, Urumqi 830011, china Graduate University of the chinese academy of sciences, beijing 100039, china Chemical Laboratory for Atmosphere, china meteorological Administration, beijing 100081, china Urumqi Desert Meteorology, china meteorological Administration, Urumqi 830002, china Grad Univ Chinese Acad Sci Beijing 100039 Peoples R China china Meteorol Adm Chem Lab Atmosphere Beijing 100081 Peoples R China china Meteorol Adm Urumqi 830002 Peoples R China chinese Acad Sci Xinjiang Inst Ecol & Geog Urumqi 830011 Peoples R China

glacial-interglacialgyrations 的出现能与 Milankovitch 理论被解释，这通常被考虑。然而，在理论的一些问题的答案还当前没被导出。在从 CentralAsia 研究东方灰尘运输以后，我们发现了在东方灰尘运输和全球温度减少之间有积极反馈... 详细信息

glacial-interglacialgyrations 的出现能与 Milankovitch 理论被解释，这通常被考虑。然而，在理论的一些问题的答案还当前没被导出。在从 CentralAsia 研究东方灰尘运输以后，我们发现了在东方灰尘运输和全球温度减少之间有积极反馈机制。这在北半球的 thehigh 纬度区域放大太阳的放射变化的效果，并且导致全球冰川的时代的出现。积极反馈机制在北半球的 thehigh 纬度区域以太阳的放射的减小开始。随后，全球温度减少，全球冰川的历元发生，在哪个枢轴的因素是从 CentralAsia 的东方灰尘运输。与积极反馈机制的理论，在 Milankovitch 理论的一些问题能被解决很好。

关键词：冰川间冰期高纬度地区北半球太阳辐射正反馈机制

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PRELIMINARY STUDY ON SAND - DUST STORM DISASTER AND COUNTERMEASURES IN china

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chinese Geographical Science 2002年第1期12卷 9-13页

作者： ZHANG Qing yang, ZHAO Xi you, ZHANG Yuan, LI Li(chinese academy of meteorological sciences, beijing 100081, P.R.china) chinese academy of Meterological sciences Beijing P. R. China

As a kind of natural disasters, sand dust storms frequently occur in deserts and their surrounding areas. The occurrence of this disaster in china′s northwest and north china has exerted an extremely adverse effect upon the environment in china. The management of sand dust storms is of a systematic project closely related with the environment such as agriculture, ecosystem, forestry, water conservancy, meteorology and other aspects. Therefore, studies of the formation, the basic features, causes, temporal spatial distribution, developing trend and related disasters of sand dust storms in china are conducted based on satellite data. The experience of sand dust storms control and countermeasures in the United States and some other countries are referred. Meanwhile, preliminary countermeasures relating to sand dust storms in china are proposed.

关键词： sand-dust storm in china spatial and temporal distribution meteorologicaldisaster countermeasures of sand-dust storms

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Direct Optimization of Low-thrust Many-revolution Earth-orbit Transfers

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chinese Journal of Aeronautics 2009年第4期22卷 426-433页

作者： Gao Yang academy of Opto-Electronics,chinese academy of sciences,beijing 100190,china [a]academy of Opto-Electronics Chinese Academy of Sciences Beijing 100190 China

Low-thrust Earth-orbit transfers with 10^- 5-order thrust-to-weight ratios involve a large number of orbital revolutions which poses a real challenge to trajectory optimization. This article develops a direct method to optimize minimum-time low-thrust many-revolution Earth-orbit transfers. A parameterized control law in each orbit, in the form of the true optimal control, is proposed, and the time history of the parameters governing the control law is interpolated through a finite number of nodal values. The orbital averaging method is used to significantly reduce the computational workload and the trajectory optimization is conducted based on the orbital averaging dynamics expressed by nonsingular equinoctial elements. Furthermore, Earth＇s shadowing and perturbation effects are taken into account. The optimal transfer problem is thus converted to the parameter optimization problem that can be solved by nonlinear programming. Taking advantage of the mapping between the parameterized control law and the Lyapunov control law, a technique is proposed to acquire good initial guesses for optimization variables, which results in enlarged convergence domain of the direct optimization method. Numerical examples of optimal Earth-orbit transfers are presented.

关键词： low thrust orbital transfer optimization direct method orbital averaging Lyapunov method

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Comparative analysis of temperature and CO2 fluxes for winter wheat in Tibetan Plain and North china Plain using the EMD method

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Progress in Natural Science:Materials International 2006年第10期16卷 1066-1071页

作者： JIANG Zhaoyang, YU Qiang, LEI Shuhe, WANG Tianduo, SUN Xiaomin and ZHANG Renhua ( chinese academy of meteorological Science, beijing 100081, china Institute of Geographic sciences and Natural Resources Research, chinese academy of sciences, beijing 100101, china Mathematics Department, Ocean University of china, Qingdao 266071, china Shanghai Institute of Plant Physiology and Ecology, chinese academy of sciences, Shanghai 200032, china) [a]chinese academy of meteorological Science Beijing China [b]chinese academy of sciences Institute of Geographic sciences and Natural Resources Research Beijing China [c]Mathematics Department Ocean University of China Qingdao China [d]chinese academy of sciences Shanghai Institute of Plant Physiology and Ecology Shanghai China

Comparative study of spectral properties of temperature and CO2 fluxes measured by eddy covariance method at Yucheng (36°57'N, 116°36'E, 28 m a.s.l., in the North china Plain) and at Lhasa (29°41'N, 91°20'E, 3688 m a.s. 1., on the Tibetan Plateau) is described using the empirical mode decomposition (EMD) method. The main results are: (1) The intrinsic oscillation modes or intrinsic mode functions (IMFs) were extracted from data of temperature ( T) and CO2 fluxes (F) measured at Yucheng ( T1 and F1) and Lhasa ( T2 and F2) . (2) Hilbert transform was applied to these IMF components, then the Hubert-Huang spectra and the marginal spectra of these data were obtained. (3) Comparison of temperature and CO2 fluxes in North china Plain and on Tibetan Plain illustrated that the characteristic frequencies corresponding to T1, F1, T2 and F2 are 0.05 Hz, 0.03 Hz, 0.014 Hz and 0.005 Hz, respectively.

关键词： empirical mode decomposition (EMD) intrinsic mode function (IMF) flux Hilbert transform wheat Tibet.

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Climate effects of nuclear war in china

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Journal of Environmental sciences 1993年第2期5卷 230-240页

作者： Cao Hongxingchinese academy of meteorological sciences, beijing 100081, chinaWang Yongzhong Lin Yunmeibeijing Institute of Meteorology, beijing 100081, china chinese academy of meteorological sciences Beijing 100081 China. China

By utilizing simulations of climatic respponse to nuclear smoke, which were made by the Lawrence Livermore National Laboratory, USA, climate change in china induced by a large-scale nuclear war is analysed. Remarkable climate change in china following nuclear smoke injections is found. The surface air temperature decreases dramatically around all china, surface cooling is 13 ℃ averaging over whole china in July and maximum cooling is 23. 4 ℃ , 3 ℃ cooling in January and maximum 8℃ for the 150 Tg smoke injection (equivalent to the base-line nuclear war). However, the change in temperature is unhomogeneous, implying that the rise in temperature happens over some parts of china. An averaging precipitation decrease in many of months of the experimental year. The precipitation defect is dependent on a scale of nuclear war, the deduction is 1.8mm/day averaging over china in July in the 150 Tg smoke injection, and 0.1 mm/d in January. Nevertheless, the precipitation enhancement in a few months over some regions is found. This dramatic climate change brings catastrophe to agriculture, ecology, as well as socio-economics.

关键词： nuclear winter climate simulation precipitation change.

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Impacts of climate change on development rate and production of corn in the northeastern china

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Journal of Environmental sciences 1993年第2期5卷 201-208页

作者： Guo Jianping, Gao Suhua Pan Yaruchinese academy of meteorological sciences, beijing 100081, china chinese academy of meteorological sciences Beijing 100081 China China

In this paper, the impacts of climate change on development rate and production of corn in the northeastern china are discussed. The results show that the higher the temperature is, the faster the development rate will be. And the more the precipitation is, the slower the development rate will be. Of which, air temperature is the controlling factor of corn development rate. The influences of development rate on corn yield are remarkable. The impacts of development rate on production in first and last periods are great, and small in the middle two periods. The development rate is positive by relate with corn production from sowing to emergence stage and negative during other periods. So, it is very important to arrange a suitable sowing time for com cultivating in the northeastern china.

关键词： climate change development rate corn.

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Size-dependent hydroxyl radicals generation induced by SiO_2 ultra-fine particles: The role of surface iron

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Science china Chemistry 2009年第7期52卷 1033-1041页

作者： SHANG Yu1, ZHU Tong1, LI Yi1,2 & ZHAO JinCai3 1 College of Environmental sciences and Engineering, Peking University, beijing 100871, china 2 chinese academy of meteorological sciences, beijing 100871, china 3 Institute of Chemistry, chinese academy of sciences, beijing 100871, china 1. College of Environmental sciences and Engineering Peking University Beijing 100871 China 2. chinese academy of meteorological sciences Beijing 100871 China 3. Institute of Chemistry Chinese Academy of Sciences Beijing 100871 China

Oxidative stress and hydroxyl radicals (·OH) play important roles in adverse health effects caused by inhalable ambient air particles (PM10). The ultra-fine fraction of PM10 has been hypothesized as one of the critical contributors to ·OH generation. Both in vivo and in vitro studies have shown that ultra-fine particles (UFPs) or nano-particles generate more ·OH than larger particles with identical mass and composition. Both the surface area and surface-adsorbed redox-active metals have been suggested as factors to determine the oxidative capacity of UFPs. In this study, the ·OH-generating capability of dif-ferent sizes of SiO2 particles was investigated in order to determine which factor influences particle-induced ·OH generation. The amount of ·OH generated in both acellular and cellular systems was quantified using a capillary electrophoresis method following exposure to SiO2 particles with diameters of 14, 100, and 500 nm. The amount of ·OH was strongly dependent on particle size, and a significant enhancement was observed only with 14 nm particles. Further studies indicated a close association between ·OH and iron ion concentration (R2 = 0.812, p<0.01). Washed particles, with their surface iron being removed, did not generate ·OH. The iron-containing leachate from these washings was able to enhance ·OH production as untreated particles did. Therefore, the presence of adsorbed iron on the surface of the SiO2 particles is presented as a possible mechanism of UPFs-induced ·OH generation. The SiO2 acted as an inert substrate, and the surface of ultra-fine SiO2 particles acted as a carrier for iron.

关键词： ultra-fine particles nano-particles ·OH oxidative stress size-effect

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Strong decays of N~*(1535) in an extended chiral quark model

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Science china(Physics,Mechanics & Astronomy) 2009年第10期52卷 1452-1457页

作者： AN ChunSheng1,2,3 & ZOU BingSong1,2,3 1 Institute of High Energy Physics,chinese academy of sciences,beijing 100049,china 2 Theoretical Physics Center for Science Facilities,chinese academy of sciences,beijing 100049,china 3 Graduate University of chinese academy of sciences,beijing 100049,china Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Theoretical Physics Center for Science Facilities Chinese Academy of Sciences Beijing 100049 China Graduate University of chinese academy of sciences Beijing 100049 China

The strong decays of the N*(1535) resonance are investigated in an extended chiral quark model by including the low-lying $ qqqq\bar q $ components in addition to the qqq component. The results show that these five-quark components in N*(1535) contribute significantly to the N*(1535) → Nπ and N*(1535) → Nη decays. The contributions to the Nη decay come from both the lowest energy and the next-tolowest energy five-quarks components, while the contributions to the Nπ decay come from only the latter one. Taking these contributions into account, the description for the strong decays of N*(1535) is improved, especially for the puzzling large ratio of the decays to Nη and Nπ.

关键词： N*(1535) strong decays five-quark components

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Application of asymptotic waveform approximation technique to hybrid FE/BI method for 3D scattering

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Science in china(Series F) 2007年第1期50卷 124-134页

作者： PENG Zhen1,2,3 & SHENG XinQing2 1 Institute of Electronics, chinese academy of sciences, beijing 100080, china 2 Department of Electronic Engineering, beijing Institute of Technology, beijing 100081, china 3 Graduated University of chinese academy of sciences, beijing 100039, china 1. Institute of Electronics Chinese Academy of Sciences Beijing 100080 China 2. Department of Electronic Engineering Beijing Institute of Technology Beijing 100081 China 3. Graduated University of chinese academy of sciences Beijing 100039 China

The asymptotic waveform evaluation （AWE） technique is a rational function approximation method in computational mathemetics, which is used in many appllcations in computational electromagnetlca. In this paper, the performance of the AWE technique in conjunction with hybrid finite element/boundary integral （FE/BI） method is firstly Inveetlgeted. The formuletlon of the AWE applied in hybrid FE/BI method is given in detail. The characteristic implementation of the application of the AWE to the hybrid FE/BI method is discussed. Numarlcel results demonstrate that the AWE technique can greatly speed up the hybrid FE/BI method to acquire wide-band and wide-angle backecatter radar-cross-section （RCS） by complex targets.

关键词： hybrid FE/BI AWE electromagnetic scattering RCS

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