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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. department 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

Analysis on the Physical Mechanism of Snowstorm Generated by the South Cyclone

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Meteorological and Environmental Research 2011年第4期2卷 33-38页

作者： CAO Dian-bin1, 2. CHEN Li2. ZHANG Hong-wei2. WU Qiong2. PAN Hua-sheng2.1. department of atmospheric and Oceanic {2., Physics College, Peking university, Beijing 100871, China 2. Heilongjiang Meteorological Bureau, Harbin 150001, China

[Objective] The research aimed to study the physical mechanism of snowstorm which was generated by the south cyclone. [Method] By using the routine meteorological observation data, satellite data and MM5 mode output data, the snowstorm weather in the east of Heilongjiang Province during March 4-6, 2.07 was analyzed. The physical mechanism of snowstorm which was generated by the south cyclone was discussed. [Result] Jianghuai cyclone advanced northward to generate the snowstorm. In the middle and high latitudes, the good cold air must coordinate with it. Meanwhile, the south cyclone provided the good high temperature condition and the rich water vapor condition for the snowstorm generation. The snowstorm generation must have the close coordination of airflows in the high and low levels, and the strong convergence ascending movement was generated. The vertical movement made that the atmospheric energy could be transformed. When the snowstorm was generated, there was the strong vertical ascending movement in the high altitude. The snowstorm falling zone was in the north side of big value zone. The variation of TBB cloud top temperature intensity as the time had the good guidance role for forecasting the starting time of strong snowfall. The convergence center of water vapor flux divergence and the zone where the temperature drew point difference in 92. hPa layer ≤ 4 ℃ had the good corresponding relationships with the snowstorm falling zone and the snowfall strong center. It provided the good reference index for forecasting the falling zone and strong center of snowstorm. Under the restriction of moist potential vorticity conservation, for the leaning of θe surface, the atmospheric horizontal wind was vertical, or the wet baroclinicity increased, which could cause the significant development of vertical vorticity. The bigger θe surface leaning was, the stronger the cyclonic vorticity was. It was easy to cause the strong precipitation weather. When the high-altitude dry

关键词： South cyclone Snowstorm Physical mechanism Cloud top temperature Dry invasion China

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

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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 39%） 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

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.

Palaeoclimate simulation of Little Ice Age

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Progress in Natural Science:Materials International 2004年第8期 68-76页

作者： LIU Jian 1, CHEN Xing 2. WANG Sumin 1 and ZHENG Yiqun 1 (1. Nanjing Institute of Geography and Limnology, Chinese Academy of sciences, Nanjing 2.0008, China 2. department of {2. Science, Nanjing university, Nanjing 2.0093, China) Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210008 China department of atmospheric Science Nanjing University Nanjing 210093 China

Little Ice Age (LIA) is a typical cold climate period in global scope with a profound impact upon human society. In this study, a coupled global atmospheric circulation model including the land processes (AGCM + SSiB) is used to perform the simulation of LIA climate. Under the control of solar radiation reduction mechanism, the decrease of temperature is more obvious in summer than in winter; meanwhile, there is regional difference in the change of winter temperature. But the temperature decrease is the main characteristic of the annual mean temperature. Volcanic dust has an evident effect on the winter temperature decrease, but to a less extent than the solar radiation. The synchronous function caused by the reduction of solar radiation and the increase of optic depth of volcanic dust has a superposed strengthening effect on the temperature decrease in large regions. Promotion of the vegetation cover rate profits the increase of temperature, and vise versa. Certain decrease of solar radiation will favor the increase of summer monsoon precipitation in East Asia. The increase of optic depth of volcanic dust does not have a significant effect on the annual precipitation in most parts of Eurasian continent. The composite effect of the decrease of solar radiation and the increase of volcanic dust makes the summer monsoon precipitation in East China increase, and that in South Asia decrease. Together with vegetation change, the result shows that precipitation increases with the increase of vegetation coverage (e.g. East Asia), and when the vegetation coverage reduces (e.g. North Africa) the precipitation will decrease, too.

关键词： Little Ice Age model simulation East Asia.

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, lanzhou 73.000 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.

Design of a new dynamical core for global atmospheric models based on some efficient numerical methods

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Science China Mathematics 2004年第z1期47卷 4-21页

作者： WANG Bin, WAN Hui, Jl Zhongzhen, ZHANG Xin, YU Rucong, YU Yongqiang & LIU HongtaoState Key Laboratory of Numerical Modeling for atmospheric sciences and Geophysical Fluid Dynamics, Institute of atmospheric Physics, Chinese Academy of sciences, Beijing 10002., China department of Computational Mathematics, Academy of Mathematics and System sciences, Peking university, Beijing 100871, China Chinese Acad Sci Inst Atmospher Phys State Key Lab Numer Modeling Atmospher Sci & Geop Beijing 100029 Peoples R China Peking Univ Acad Math & Syst Sci Dept Computat Math Beijing 100871 Peoples R China

A careful study on the integral properties of the primitive hydrostatic balance equations for baroclinic atmosphere is carried out, and a new scheme todesign the global adiabatic model of atmospheric dynamics ispresented. This scheme includes a method of weighted equal-areamesh and a fully discrete finite difference method with quadraticand linear conservations for solving the primitive equationsystem. Using this scheme, we established a new dynamical corewith adjustable high resolution acceptable to the availablecomputer capability, which can be very stable without anyfiltering and smoothing. Especially, some important integralproperties are kept unchanged, such as the anti-symmetries of thehorizontal advection operators and the vertical convectionoperator, the mass conservation, the effective energy conservationunder the standard stratification approximation, and so on. Somenumerical tests on the new dynamical core, respectively regardingits global conservations and its integrated performances inclimatic modeling, incorporated with the physical packagesfrom the Community atmospheric Model Version 2.(CAM2. of NationalCenter for atmospheric Research (NCAR), are included.

关键词： dynamical core, equal-area mesh, anti-symmetry, effective energy conservation.

THE PHASE RELATION BETWEEN ACCUMULATIVE EFFECT OF SOLAR ECLIPSE AND EL NINO

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南京大学学报(自然科学) 1999年第6期35卷 135-137页

作者： Lin Zhen Shan (department of atmospheric {2., Nanjing university, 2.0093, Nanjing,PRC) 南京大学江苏南京 2 1 0 0 93

ＢｙａｎａｌｙｚｉｎｇａｌｌｔｈｅｄａｔａｏｆＥｌＮｉｎｏａｎｄｔｈｅｓｏｌａｒｅｃｌｉｐｓｅｓｆｒｏｍ1948ｔｏ1998,ｓｏｍｅｃｏｍｐｌｅｘｒｅｌａｔｉｏｎｓｂｅｔｗｅｅｎｔｈｅｓｏｌａｒｅｃｌｉｐｓｅｓａｎｄＥｌＮ... 详细信息

ＢｙａｎａｌｙｚｉｎｇａｌｌｔｈｅｄａｔａｏｆＥｌＮｉｎｏａｎｄｔｈｅｓｏｌａｒｅｃｌｉｐｓｅｓｆｒｏｍ1948ｔｏ1998,ｓｏｍｅｃｏｍｐｌｅｘｒｅｌａｔｉｏｎｓｂｅｔｗｅｅｎｔｈｅｓｏｌａｒｅｃｌｉｐｓｅｓａｎｄＥｌＮｉｎｏａｒｅｆｏｕｎｄａｓｆｏｌｌ?..

关键词： El Nino eclipse prediction

Annual precipitation fields secular variation over global land areas for 1948—2.00

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Chinese Science Bulletin 2003年第3期48卷 281-286页

作者： SHI Neng & CHEN Luweng department of atmospheric {2., Nanjing Institute of Meteorology, Nanjing 2.0044, China department of atmospheric {2. Nanjing Institute of Meteorology Nanjing 210044 China

The secular variation over the global land an-nual precipitation (GLAP) fields for 1948—2.00 is investi-gated. Evidence suggests that the GLAP abruptly reduced around 1978 and experienced a decrease of 0.54 mm/a, on average. Fuzzy clustering is used to group the annual pre-cipitation over commonly-used 36 latitudes belts into six belts for examining its secular variation. The results show that, except northern high-latitudes (60°—90°N) where it is slightly increased, the precipitation is decreased, especially in 35°N—35°S, and the diminution is the maximum of 0.98 mm/a at tropics. Moreover, identification of 1948—2.00 flood/drought years on a global basis is made, showing no-ticeable interdecadal variations. During the years of warm (cold) events the precipitation decreases (increases) by 15.4 mm (14.4 mm) per year, on average. It can be assumed that global warming and frequent ENSO occurrences from the end of the 1970s maybe serve as the root cause of the dimi-nution.

关键词：全球降水长期变化年降水 ENSO 陆地 1948-2.00年