检索结果-南通市图书馆

Science china Earth sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2,3 & WANG Huijun2 1. Nansen-Zhu International Research Center, institute of atmospheric physics, chinese academy of sciences, beijing 100029, china 2. Department of atmospheric Science, Yunnan University, Kunming 650091, china 3. Graduate University of the chinese academy of sciences, beijing 100049, china 1. Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Department of atmospheric Science Yunnan University Kunming 650091 China 3. Graduate University of the chinese academy of sciences Beijing 100049 China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

Extraseasonal ensemble numerical predictions of winter climate over china

在线全文

学校读者我要写书评

暂无评论

chinese Science Bulletin 2003年第19期48卷 2121-2125页

作者： LANG Xianmei, WANG Huijun & JIANG Dabang Nansen-Zhu International Research Center and LASG, institute of atmospheric physics, chinese academy of sciences, beijing 100029, china Nansen Zhu International Research Center and LASG institute of atmospheric physics Chinese Academy of Sciences China

Using the nine-level atmospheric General Circulation Model developed at the institute of atmospheric physics (IAP9L-AGCM) under the chinese academy of sciences, 30-year extraseasonal short-term ensemble hincast of winter climate is performed, with integrations starting from annual autumn during 1969—1998. Winter climate predictability over china is then evaluated for the first time. It follows that the predictability is higher in tropics than in extratropics. Also, it is higher over ocean compared with land, especially for surface air temperature. With height increasing in troposphere, the predictability of geopotential height slightly changes zonally, but for weakening of band-ship distribution and dropping near the date line. Of all analyzed variables, the prediction skill of air temperature and geopotential height (precipitation) is the highest (smallest). In addition, the predictability of winter climate over china and even East Asia enhances obviously during ENSO cycle, especially during La Nia phase. Simulation comparison against verifying analysis for surface temperature anomaly exhibits the model抯 skill in predicting surface temperature抯 interannual variation trend in winter.

关键词：冬季气候中国气候预报数字模型表面温度

Zonal propagation of kinetic energy and convection in the South china Sea and Indian monsoon regions in boreal summer

在线全文

学校读者我要写书评

暂无评论

Science china Earth sciences 2004年第12期47卷 1076-1084页

作者： CHEN Longxun 1 ,GAO Hui 2 ,HE Jinhai 2 ,TAO Shiyan 3 & JIN Zuhui 3 1.chinese academy of Meteorological sciences,beijing 100081,china 2.Nanjing institute of Meteorology,Nanjing 210044,china 3.institute of atmospheric physics,chinese academy of sciences,beijing 100029,china 1. chinese academy of Meteorological sciences 100081 Beijing China 2. Nanjing institute of Meteorology 210044 Nanjing China 3. chinese academy of sciences Institute of Atmospheric Physics 100029 Beijing China

Zonal propagation of kinetic energy (KE) and convection in the South china Sea (SCS) and Indian summer monsoon areas are examined in present study. Results suggest that the SCS and Indian summer monsoon prevailed regions (5 —15°N) are dominated by the southwesterly wind, however, the disturbances of KE at 850 hPa and convection are observed mainly coming from the western Pacific Ocean (140—150°E), after passing through the SCS, and westward propagated into the Bay of Bengal (90—100°E). In the Indian summer monsoon domain, where the disturbances of KE are found mainly coming from the Arabian Sea (AS) and eastward propagated into the Bay of Bengal. Therefore, the SCS and the Indian summer mon- soon are quite different in zonal propagation of KE and convection. The SCS summer monsoon is mainly affected by the KE and convection coming from the tropical western Pacific. The Indian summer monsoon, however, can be partly influenced by the AS and the SCS summer monsoon. The analysis also suggests that the interaction region between the SCS and the Indian summer monsoon is around 90—95°E, rather than 105°E as proposed by earlier studies.

关键词： zonal propagation of KE and convection, East Asian monsoon, Indian monsoon.

A subsurface runoff parameterization with water storage and recharge based on the Boussinesq-Storage Equation for a Land Surface Model

在线全文

学校读者我要写书评

暂无评论

Science china Earth sciences 2006年第6期49卷 622-631页

作者： TIAN Xiangjun1,2, XIE Zhenghui1, ZHANG Shenglei1 & LIANG Miaoling1 1. LASG, institute of atmospheric physics, chinese academy of sciences, beijing 100029, china 2. Graduate School of the chinese academy of sciences, beijing 100039, china 1. LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 2. Graduate School of the chinese academy of sciences Beijing 100039 China

Subsurface runoff in a land surface model is usually parameterized as a single-valued function of total storage in a basin aquifer reservoir. This kind of parameterization is often sin-gle-valued function of storage-discharge under a steady or “quasi-steady” state, which cannot rep-resent the influence of aquifer recharge on subsurface runoff generation. In this paper, a new sub-surface runoff parameterization with water storage and recharge based on the Boussinesq-storage equation is developed. This model is validated by a subsurface flow separation algorithm for an ex-ample river basin, which shows that the new model can simulate the subsurface flow reasonably.

关键词： Zsubsurface runoff parameterization Boussinesq-storage equation waterstorage and recharge

Differentiation transforming system

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2009年第3期19卷 397-406页

作者： Qiang Chenga,b,c,*, Haibin Zhang d, Bin Wanga, Yonghua Zhao c a LASG, institute of atmospheric physics, chinese academy of sciences, beijing 100029, PR china b LSEC, institute of Computing Mathematics, chinese academy of sciences, beijing 100080, PR china c SC, institute of Computer Network Information Center, chinese academy of sciences, beijing 100190, PR china d College of Applied sciences, beijing University of Technology, beijing 100124, PR china [a]LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 PR China [b]LSEC Institute of Computing Mathematics Chinese Academy of Sciences Beijing 100080 PR China [c]SC Institute of Computer Network Information Center Chinese Academy of Sciences Beijing 100190 PR China [d]College of Applied Sciences Beijing University of Technology Beijing 100124 PR China

The differentiation transforming (DFT) system is developed to produce the tangent linear codes, which is used to calculate the Jaco- bian- and the Hessian-vector products with no truncation errors. This paper first gives the introduction of the functionality and features of the DFT system, and then discusses several techniques for the implementation of automatic differentiation tools, including data depen- dence analysis, singular differentiation and code optimization. Finally, the codes generated with DFT used in several applications have been demonstrated.

关键词： Jacobian Hessian Tangent linear model Automatic differentiation

Numerical simulation of Meiyu front and the diagnosis of moist vorticity vector

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2007年第11期17卷 1341-1347页

作者： Ping Fan1,2 and Luo Zhexian2(1. institute of atmospheric physics, chinese academy of sciences, beijing 100029, china 2. Nanjing University of Information sciences & Technology, Nanjing 210044, china) institute of atmospheric physics Chinese Academy of Sciences Beijing 100029 China Nanjing University of Information sciences & Technology Nanjing 210044 China

Moist vorticity vector is introduced to study the development and evolution of mesoscale convective vortex (MCV) in the Meiyu front precipitation with the Advanced Regional Predication System (ARPS). In this study, the heavy rainfall is simulated to investigate the genesis, development and dissipation of middle scale convective vortex, which occurred from 0000 UTC 3 July to 1200 UTC 5 July over the Jianghuai River valley. Moist vorticity vector (MVV) has zonal, radial and vertical components in its 3D spatial distribution. The simulation shows that the vertical component of moist vorticity vector well demonstrates the spatial distribution characteristics of middle scale convective vortex, especially in the process of Meiyu front precipitation. Diagnosis upon zonal, radial averaged and mass-integrated quantities of MVV shows that its vertical component and the surface precipitating ratio are in phase with a correlation coefficient of 0.68, indicating that the vertical component of MVV is closely associated with the Meiyu front precipitation. In addition, the tendency of the vertical component of MVV is mainly determined by the interaction between the vorticity and the zonal and radial gradient of condensational or depositional heating.

关键词： moist vorticity vector mesoscale convective vortex Meiyu front precipitation

The Alternating-Direction Schemes and Numerical Analysis for the Three-dimensional Seawater Intrusion Simulation

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta Mathematicae Applicatae Sinica 2002年第3期18卷 389-404页

作者： Zhi-yue ZhangLASG, institute of atmospheric physics, chinese academy of sciences, beijing 100029, china & School of Mathematics and Computer Science, Nanjing Normal University, Nanjing 210097, china LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China School of Mathematics and Computer Science Nanjing Normal University Nanjing China

Both numerical simulation and theoretical analysis of seawater intrusion in coastal regions are of great theoretical importance in environmental sciences. The mathematical model can be described as a coupled system of three dimensional nonlinear partial differential equations with initial-boundary value problems. In this paper, according to the actual conditions of molecular and three-dimensional characteristic of the problem, we construct the characteristic finite element alternating-direction schemes which can be divided into three continuous one-dimensional problems. By making use of tensor product algorithm, and priori estimation theory and techniques, the optimal order estimates in H1 norm are derived for the error in the approximate solution.

关键词： Three-dimensional seawater intrusion characteristic finite element alternating-direction optimal order estimate in H^1

Water-vapor source shift of Xinjiang region during the recent twenty years

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2007年第5期17卷 569-575页

作者： Dai Xingang , Li Weijing , Ma Zhuguo and Wang Ping (Key Laboratory of Regional Climate-Environment for Temperate East Asia, institute of atmospheric physics, chinese academy of sciences, beijing 100029, china Laboratory for Climate Change, chinese Meteorological Administration, beijing 100081, china) [a]Key Laboratory of Regional Climate-Environment for Temperate East Asia Institute of Atmospheric PhysicsChinese Academy of Sciences Beijing China [b]Laboratory for Climate Change chinese Meteorological Administration Beijing China

The aim of this paper is to investigate the climate water-vapor sources of Xinjiang region and their shifts during the past 20 years. First, the principle and steps are roughly regulated to seek the water-vapor sources. Second, the climate stationary water-vapor transport in troposphere is calculated to distinguish where the water vapor comes from by ERA-40 reanalysis. In addition, the collocation between the transport and the atmospheric column water vapor content is analyzed. The results show that the major vapor comes from the west side of Xinjiang for mid-month of seasons, apart from July while the water vapor comes from the north or northwest direction. The water vapor sources are different for different seasons, for example, the Caspian Sea and Mediterranean are the sources in January and April, the North Atlantic and the Arctic sea in July, and the Black Sea and Caspian Sea in October, respectively. In recent ten years more water vapor above Xinjiang comes from the high latitudes and the Arctic sea with global warming, and less from Mediterranean in comparison with the case of 1973—1986. In fact, the air over subtropics becomes dry and the anomalous water vapor transport direction turns to west or southwest during 1987—2000. By contrast, the air over middle and high latitudes is warmer and wetter than 14 years ago.

关键词： global warming water-vapor source water-vapor transport precipitable water Xinjiang climate inter-decadal change.

Adjoint method for the optimum planning of industrial pollutant sources

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china Earth sciences 2005年第8期48卷 1270-1279页

作者： LIU Feng1,2, HU Fei2 & ZHU Jiang2 1. College of Environmental sciences, Peking University, beijing 100871, china 2. LAPC, institute of atmospheric physics, chinese academy of sciences, beijing 100029, china 1. College of Environmental sciences Peking University 100871 Beijing China 2. LAPC Institute of Atmospheric Physics Chinese Academy of Sciences 100029 Beijing China

The optimum planning of industrial pollutant sources, which optimizes the economic object without violating environmental constraints, is an important and hard task to be conquered. In this paper, an adjoint method is developed to solve the problem. The penalty function is in-troduced to deal with the environmental inequality constraints, and Lagrange function is con-structed to derive the adjoint equation and the gradient of the object function. In this means, the gradient of the object function can be calculated by solving the adjoint equation, and the infor-mation from the gradient is used to make the object function descend and approach to an optimal solution after some iterations. A two-dimensional, simplified model is used for numerical experi-ments. The theoretical derivations are verified by the results of the experiments. Furthermore, the adjoint method is shown to be of excellent convergence and efficiency, which is adaptive to the fast development of air quality numerical models and super computers.

关键词： optimum planning, industrial pollutant sources, adjoint equation, penalty function, gradient.

Seasonal variation of global stratosphere-troposphere mass exchange

在线全文

学校读者我要写书评

暂无评论

Progress in Natural Science:Materials International 2007年第12期17卷 1466-1475页

作者： Guo Dong1,2, Lu Daren2 and Sun Zhaobo1(1. institute of atmospheric sciences, Nanjing University of Information Science and Technology, Nanjing 210044, china 2. LAGEO, institute of atmospheric physics, chinese academy of sciences, beijing 100029, china) institute of atmospheric sciences Nanjing University of Information Science and Technology Nanjing 210044 China LAGEO Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

By Wei formula in pressure coordinate, the stratosphere-troposphere mass exchange (STME) is diagnosed globally for 44 years from 1958 to 2001 using the European Center for Medium-Range Weather Forecasts (ECMWF) reanalysis datasets. Regions of mass flux into the stratosphere are found over Indonesia, bay of Bangladesh and the mid-west coast of South Africa. Compensating mass outflow from the stratosphere appears mainly over mid-latitudes near large-scale troughs. Upward and downward transport of mass at the middle and high latitudes accompany with each other. Mass flux into troposphere is stronger in autumn and winter than in spring and summer. Strong downward mass flux into the troposphere occurs in eastern Asia the whole year with nearly stable sites. Although the area of eastern Asia accounts for only 5.6% of that of the northern hemisphere (NH), its net mass exchange reaches 15.83% of that of the NH, which means that research on STME of eastern Asia is greatly important to that of the NH and even the global areas. Air across the tropopause enters more from stratosphere to troposphere than that from troposphere to stratosphere, which is possibly related with systematic bias of the assimilated datasets and with persistent rise of the tropopause height. Contributions of the mass exchange and the mass flux exchange in the NH and southern hemisphere (SH) on their latitudes increase from equator to pole, with larger contributions in the NH. Mass exchange and mass flux exchange per areas at high latitudes are larger than that at low latitudes, which means greater mass exchange efficiency at high latitudes.

关键词： stratosphere troposphere mass exchange seasonal variation.