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Paleoenvironmental records from the northern South China Sea since the Last Glacial Maximum

Acta Oceanologica Sinica 2010年第3期29卷 46-62页

作者： GE Qian CHU Fengyou XUE Zuo LIU J Paul DU Yuansheng FANG Yinxia Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China Key Laboratory of Submarine Geosciences State Ocean Administration Hangzhou 310012 China department of Marine Earth and Atmospheric Sciences North Carolina State University Raleigh NC 27695 USA

Core ZHS-176 contains the paleoenvironmental records from the northern South China Sea （NSCS） since the Last Glacial Maximum （LGM）. A coupled approach based on clay mineral assemblages, planktonic foraminiferal oxygen and carbon isotopes, and calcium carbonate content is used to trace the sources of the fine-grained sediment and to investigate the paleoenviornmental evolution in this area. Clay mineral assemblages are dominated by illite （average about 3.%） and chlorite （about 2.%）, which comes mainly from Taiwan and the East China Sea. Kaolinite, which accounts for about 13., comes mainly from the Zhujiang （Pearl） River, and Luzon Island is the main source for smectite （about 2.%）. The planktonic foraminiferal oxygen isotopic oscillations during the last glacial period are coeval with climate variations recorded in the Greenland ice core and Western Pacific sediment. These variations include the LGM, Heinrich event 1, Bφlling-Allerφd （B/A）, and Younger Dryas. For the Holocene, three periods of strong precipitation （S1-S3. and three periods of weak precipitation （W1-W3. are identified. The oxygen isotopic record exhibits corre-lation with climate records from distant regions, including the high-latitude Northern Hemisphere, providing evidence for global tele-connection among regional climate. A brief, negative planktonic foraminiferal carbon isotopic excursion during B/A reflects increased methane released from marine gas hydrate due to the rapid warming of the water. By comparing calcium carbonate content curves of the core ZHS-176 with these of other five boreholes lying above the lysocline, a remarkable low calcium carbonate event is found during the early Holocene in NSCS.

关键词： clay mineral oxygen and carbon isotopes calcium carbonate content South China Sea paleoenvironmental evolution

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Parallel Computing of Ocean General Circulation Model

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Wuhan university Journal of Natural Sciences 2001年第Z1期6卷 568-573页

作者： Zhang Li lun 1, Song Jun qiang 1, Li Xiao mei 2.1. School of Computer Science, National university of Defense Technology, Changsha 410073. China 2. {3. of Computer, Institute of Command Technology, Beijing 100081, China School of Computer Science National University of Defense Technology Changsha 410073 P.R. China

This paper discusses the parallel computing of the third generation Ocean General Circulation Model (OGCM) from the State Key Laboratory of Numerical Modeling for atmospheric Science and Geophysical Fluid Dynamics(LASG),Institute of Atmosphere Physics(IAP). Meanwhile, several optimization strategies for parallel computing of OGCM (POGCM) on Scalable Shared Memory Multiprocessor (S2.P) are presented. Using Message Passing Interface (MPI), we obtain super linear speedup on SGI Origin 2.00 for parallel OGCM(POGCM) after optimization.

关键词： parallel computing OGCM optimization strategy S2.P

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Statistical characteristics of the double ridges of subtropical high in the Northern Hemisphere

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Science Bulletin 2005年第20期 82-87页

作者： ZHAN Ruifen1,2.3. LI Jianping1 & HE Jinhai2. 1. State Key Laboratory of Numerical Modeling for atmospheric Sci- ences and Geophysical Fluid Dynamics (LASG), Institute of Atmos- pheric Physics, Chinese Academy of Sciences, Beijing 10002., China 2. department of atmospheric Sciences, Institute of Meteorology, Nan- jing {3. of Information Science and Technology, Nanjing 2.0044, China 3. Graduate School of the Chinese Academy of Sciences, Beijing 10003., China

The generality and some climatological charac- teristics of the double ridge systems of subtropical high (SH) are investigated statistically by using the daily NCEP/NCAR reanalysis data from 1958 to 1998. The results show that the SH double-ridge event is a common phenomenon in the Northern Hemisphere, with the distinct seasonal and re- gional features, that is, the majority of SH double-ridge geneses concentrate over the eastern North India Ocean- western North Pacific as well as the central North Pacific in the period from mid-July to mid-September. Especially over the western North Pacific subtropics, the SH double-ridge events are extremely active. It is found that the life cycle of most double-ridge events of western Pacific subtropical high (WPSH) is shorter but some still last longer. The WPSH dou- ble-ridge events occur most frequently from July to Septem- ber, while there is a paucity of occurrences during Novem- ber-March. Also, it is shown that the WPSH double-ridge events have a strong interannual variation with a certain periodicity which possesses a remarkably abrupt change in the mid-1970s. Additionally, the relationship between the WPSH double ridges and the meridional movement of WPSH is discussed.

关键词： subtropical high double ridges statistical characteristics meridional movement.

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Hierarchical structures in climate and atmospheric turbulence

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Progress in Natural Science:Materials International 2002年第10期 29-34页

作者： SHE Zhensu, FU Zuntao, CHEN Jiong, LIANG Shuang and LIU Shida(1. State Key Laboratory for Studies of Turbulence and Complex Systems, department of Mechanics and Engineering Sciences, Peking university, Beijing 100871, China 2. School of Physics, Peking university, Beijing 100871, China 3. LAPC, Institute of {3. Physics, Chinese Academy of Sciences, Beijing 10002., China) State Key Laboratory for Studies of Turbulence and Complex Systems，department of Mechanics and Engineering Sciences，Peking university，Beijing 100871，China LAPC，Institute of atmospheric Physics，Chinese Academy of Sciences，Beijing 10002.，China School of Physics，Peking university，Beijing 100871，China State Key Laboratory for Studies of Turbulence and Complex Systems，department of Mechanics and Engineering Sciences，Peking university，Beijing 100871，China School of Physics，Peking university，Beijing 100871，China

The climatic time series encompass many time scales, forming multi-scale climatic variations and hierarchies. The periods and magnitudes of cooling or warming, especially for extreme climatic events, vary with the time scales. On the other hand, high-frequency atmospheric turbulent motions, which are certainly related to the climatic changes, are also typical multi-scale phenomena. In this paper, certain properties of the fluctuations are examined that are invariant with the change of the time scales. Specifically, the existence of a statistical similarity law is demonstrated in climatic time series and in atmospheric turbulent motions. This is the hierarchical similarity law. Further analyses show that the hierarchical similarity law is a general property of multi-scale fluctuation systems. Therefore, the study on the hierarchical similarity law is important for understanding the inherent universal physical mechanism of complex systems in the atmospheric motions.

关键词： climate multi-scale hierarchical structure atmospheric turbulence.

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Feasibility study for joint retrieval of air density and ozone concentration profiles in the mesosphere using an ultraviolet limb-scan technique

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Progress in Natural Science:Materials International 2004年第6期 42-48页

作者： GUO Xia 1 *,LU Yao 1,2.and L Daren 1(1. LAGEO,Institute of atmospheric Physics,Chinese Academy of Sciences,Beijing 10002.,China 2. department of Physics,Beijing {2. of Science and Technology,Beijing 100081,China) LAGEO，Institute of atmospheric Physics，Chinese Academy of Sciences，Beijing 10002.，China LAGEO，Institute of atmospheric Physics，Chinese Academy of Sciences，Beijing 10002.，China department of Physics，Beijing university of Science and Technology，Beijing 100081，China

For joint retrieval of vertical distributions of both air density and ozone concentration in the mesosphere which are two of the most important atmospheric parameters in this region,a retrieval scheme is suggested by using satellite limb scan observation at two UV wavelengths,i.e. 2.5 nm and 2.6 nm . The retrieval scheme is the modification of the direct method by Aruga and Heath with two UV wavelengths and two atmospheric parameters. Feasibility study was made based on simulated limb scan radiances computed with a single scattering radiative transfer algorithms of spherical geometry developed by the present authors and the inversion technique. Results of the simulations show that it is feasible to retrieve air density and ozone concentration vertical distributions on a global basis from satellite UV limb scan over the altitude range of 50 km ～ 100 km with a vertical resolution of 1 km. The errors of the inferred profiles by using the joint inversion algorithm are greatly deduced,especially in the upper-mesosphere heights,compared with those by using the single inversion technique with a single wavelength.

关键词： mesosphere air density and ozone concentration ultraviolet limb-scan technique.

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Abrupt climate change and collapse of ancient civilizations at 2.00BC-2.00BC

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Progress in Natural Science:Materials International 2005年第10期15卷 46-52页

作者： WANG Shaowu (department of atmospheric Science, School of Physics, Peking {2., Beijing 100871, China) department of atmospheric Science School of Physics Peking University Beijing 100871 China

Plentiful evidence of historical, archaeological and palaeoclimatic studies proved that an abrupt change from wetter to drier climate occurred over the Nile Valley,the Mesopotamia, the Indus Valley and Huanghe River Valley at 2.00BC-2.00BC. The abrupt change was developed based on the general lowering of temperature in the middle latitudes, and was a strong cold event since the beginning of the Megathermal (8.5-3.0 kaBP). Collapse of Nile civilization appeared at the First Intermediate Period (2.81BC-2.40BC). Civilization of Mesopotamia began collapse following the disintegration of Akkadian Empire. This process lasted to the foundation of Babylon Kingdom from 2.00BC to 1900BC. Indus civilization abruptly fell off at 1800BC. A widespread alternation of archaeological cultures happened in China at ca. 2.00BC except only in its central part. Longsheng culture was replaced by the Erlitou culture, which is now acknowledged in China as Xia Culture. Foundation of Xia Dynasty at 2.70BC opened a new chapter in the development of Chinese civilization. Studies indicated that abrupt climate change may be caused by the weakening of the Thermohaline Circulation (THC).

关键词： 2.00BC-2.00BC abrupt climate change collapse of ancient civilization.

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Characteristics of climate change in the “significant impact zone” affected by aerosols over eastern China in warm seasons

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Science China Earth Sciences 2008年第5期51卷 730-739页

作者： SHI XiaoHui1, XU XiangDe1, XIE LiAn2.1 State Key Laboratory of Severe Weather, Chinese Academy of Meteorological Sciences, Beijing 100081, China 2.department of Marine, Earth and {3. Sciences, North Carolina State {2., Raleigh NC2.695-82.8, USA State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China department of Marine Earth and Atmospheric Sciences North Carolina State University Raleigh NC 27695-8208 USA

Through analysis of the distribution pattern and changing characteristics of atmospheric aerosols over the East Asia region during warm seasons in recent 2. a and beyond as well as their possible interac- tive relationship with a variety of meteorological elements, it is found that the high-value zone of aerosol optical depth derived from the Total Ozone Mapping Spectrometer (TOMS), its significant negative correlation zones in terms of sunshine duration (SD) and surface air temperature (SAT) and its significant positive correlation zones with low-level cloud amount (LCC) are co-located in the South China region during warm periods. Based on this finding, the region is referred to as a "significant impact zone" (SI zone) affected by aerosols. Then, a comparative analysis is made on variation differ- ences of observed SAT, SD and LCC, etc. in different regions. It is also found that the LCC is increased and the SD is decreased within the "SI zone" over eastern China during the warm season. These characteristics are more evident than those beyond the zone, while the warming trend within the zone is evidently weaker than that outside it. Studies show that since recent 2. a, under the influence of aerosols, the LCC tend to increase substantially with a clear decrease of SD and an unnoticeable warming trend within the "SI zone". Comparing with the climate change beyond the zone, the difference is significant. Therefore, the effects of atmospheric aerosols on climate is possibly one of the contri- butions to the difference of climate change existed between the southern and northern parts of the Eastern China during a warm season.

关键词： warm season significant impact zone of aerosols climate change

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Progress in studies of the climate of humid period and the impacts of changing precession in early-mid Holocene

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Progress in Natural Science:Materials International 2008年第12期18卷 1459-1464页

作者： Jianbin Huang~a Shaowu Wang~a Xinyu Wen~a Bao Yang~b a department of atmospheric Sciences,School of Physics,Peking {2.,Beijing 100871,China b Laboratory for Desert and Desertification,Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of Sciences,{3. 73.000,China [a]department of atmospheric Sciences School of Physics Peking University Beijing 100871 China [b]Laboratory for Desert and Desertification Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Studies on the climate of humid period and the impacts of changing precession in the early-mid Holocene are reviewed in this paper. High-resolution proxy data indicated that the African Humid Period,strong summer monsoon from the Arabian Sea to South Asia, northward migration of ITCZ (lntertropical Convergence Zone) over the northern South America,and the humid period of China appeared in 10.5-5.5 kaBP,10.0-6.0 kaBP,10.5 5.4 kaBP,and 11.0-8.0 kaBP,*** studies proved that summer inso- lation over the Northern Hemisphere increased following the changes of precession in the early Holocene,which increased the land-sea temperature contrasts,intensified the summer monsoon circulation in the Northern Hemisphere,and finally induced a humid climate over the area under the influence of summer ***,modeling results underestimated the increase of precipitation and the degree of northward extension of monsoon rain belt compared with palaeo-environmental *** discrepancies between the modeling results and the palaeo-environmental data may be associated with the changes of North Atlantic circulation,sea ice and veg- etation ***,climate of the humid period was not stable,in which several droughts were inlaid on centennial *** this review,perspectives for further studies of the climate change of the humid period in the early-mid Holocene are also proposed.

关键词： Holocene Humid period Precession Summer monsoon

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Distributional features of δ^(18) O in precipitation in China

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Journal of Geographical Sciences 1998年第2期8卷 57-64页

作者： ZHANG Xinpingdepartment of Geography, Hunan Normal university, Changsha 410081 CHINAYao Tandong{2. Institute of Glaciology and Geocryology, CAS,{3. CHINA

According to calculation on available data, higher δ18O exists in atmospheric precipitation of southeastern and northwestern part of China, and the lower in Northeast China and the southern QinghaiTibet Plateau. In China temperature effect appears mainly in the inner continent of midhigh latitudes and the amount effect appears in southeastern coastal regions, the YunnanGuizhou Plateau and QinghaiTibet Plateau where the influence of monsoon climate is obvious. The meteoric water lines (MWLs) of different regions are of certain divergence, which is closely related to the stable isotopic fractionations of the two processes, namely the evaporation of origins and the precipitating of vapor.

关键词： δ18 O distribution temperature effect amount effect MWL.

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Advanced information feedback strategy in intelligent two-route traffic flow systems

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Science China(Information Sciences) 2010年第11期53卷 2265-2271页

作者： DONG ChuanFei1,2. MA Xu1,3.& WANG BingHong1,4 1department of Modern Physics and Nonlinear Science Center, university of Science and Technology of China (USTC), Hefei 2.002., China 2.chool of Earth and {2. Sciences, Georgia Institute of Technology, Atlanta, GA 3.3.2. USA 3.department of Physics, Syracuse university, Syracuse, NY 13.0}4, USA 4The Research Center for Complex System Science, university of Shanghai for Science and Technology and Shanghai Academy of System Science, Shanghai 2.0093. China 1. department of Modern Physics and Nonlinear Science Center University of Science and Technology of China (USTC) Hefei 230026 China2. School of Earth and Atmospheric Sciences Georgia Institute of Technology Atlanta GA 30332 USA3. Department of Physics Syracuse University Syracuse NY 13244 USA4. The Research Center for Complex System Science University of Shanghai for Science and Technology and Shanghai Academy of System Science Shanghai 200093 China

The optimal information feedback has a significant effect on many socioeconomic systems like stock market and traffic systems aiming to make full use of resources. In this paper, we study dynamics of traffic flow with real-time information. The influence of a feedback strategy named vehicle number feedback strategy (VNFS) is introduced, in which we only calculate the vehicle number of first 500 route sites from the entrance. Moreover, the two-route traffic system has only one entrance and one exit, which is different from those in the previous work. Our model incorporates the effects of adaptability into the cellular automaton models of traffic flow, and simulation results by adopting this optimal information feedback strategy have demonstrated higher efficiency in controlling spatial distribution of traffic patterns than the other three information feedback strategies, i.e., TTFS, MVFS and CCFS.

关键词： vehicle number feedback strategy two-route selecting traffic flow intelligent vehicle cellular automaton model

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