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Theorem of turbulent intensity and macroscopic mechanism of the turbulence development

science china Earth sciences 2007年第5期50卷 789-800页

作者： HU YinQiao1,2, CHEN JinBei3,4 & ZUO HongChao2 1 Gansu Province Key laboratory of Arid Climatic Change and Reducing Disaster, Cold and Arid Regions Environment and Engi- neering Institute, Chinese Academy of sciences, lanzhou 730000, china 2 State Key Laboratory of atmospheric Boundary Layer Physics and atmospheric Chemistry (LAPC), Beijing 100029, china 3 atmospheric science college, lanzhou university, lanzhou 730000, china 4 Resource Environment Department, lanzhou Agriculture university, lanzhou 730060, china Gansu Province Key laboratory of Arid Climatic Change and Reducing Disaster Cold and Arid Regions Environment and Engineering Institute Chinese Academy of Sciences Lanzhou 730000 China State Key Laboratory of atmospheric Boundary Layer Physics and atmospheric Chemistry(LAPC) Beijing 100029China atmospheric science college Lanzhou University Lanzhou 730000 China Resource Environment Department Lanzhou Agriculture University Lanzhou 730060 China State Key Laboratory of atmospheric Boundary Layer Physics and atmospheric Chemistry LAPC Beijing 100029 China

Turbulence is one of the most common nature phenomena in everyday experience, but that is not adequately understood yet. This article reviews the history and present state of development of the turbulence theory and indicates the necessity to probe into the turbulent features and mechanism with the different methods at different levels. Therefore this article proves a theorem of turbulent transpor- tation and a theorem of turbulent intensity by using the theory of the nonequilibrium thermodynamics, and that the Reynolds turbulence and the Rayleigh-Bénard turbulence are united in the theorems of the turbulent intensity and the turbulent transportation. The macroscopic cause of the development of fluid turbulence is a result from shearing effect of the velocity together with the temperature, which is also the macroscopic cause of the stretch and fold of trajectory in the phase space of turbulent field. And it is proved by the observed data of atmosphere that the phenomenological coefficient of turbulent in- tensity is not only a function of the velocity shear but also a function of temperature shear, viz the sta- bility of temperature stratification, in the atmosphere. Accordingly, authenticity of the theorem, which is proved by the theory of nonequilibrium thermodynamics, of turbulent intensity is testified by the facts of observational experiment.

关键词： turbulence nonequilibrium thermodynamics linear thermodynamics atmosphere boundary layer Reynolds turbulence Rayleigh-Bénard turbulence

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Dusty cloud radiative forcing derived from satellite data for middle latitude regions of East Asia

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Progress in Natural science:Materials International 2006年第10期16卷 1084-1089页

作者： HUANG Jianping , WANG Yujie, WANG Tianhe and YI Yuhong ( college of atmospheric sciences, lanzhou university, lanzhou 730000, china Gansu Provincial Meteorological Bureau, lanzhou 730020, china) college of atmospheric sciences Lanzhou University Lanzhou 730000 China

The dusty cloud radiative forcing over the middle latitude regions of East Asia was estimated by using the 2-year (July 2002-June 2004) data of collocated clouds and the Earth's radiant energy system (CERES) scanner and moderate resolution imaging spectroradiometer (MODIS) from Aqua Edition IB SSF (single scanner footprint). The dusty cloud is defined as the cloud in dust storm environment or dust contaminated clouds. For clouds growing in the presence of dust, the instantaneous short-wave (SW) forcing at the top of the atmosphere (TOA) is about - 275. 7 W/m for cloud over dust (COD) region. The clouds developing in no-dust cloud (CLD) regions yield the most negative short-wave (SW) forcing ( - 311.0 W/m2), which is about 12.8% stronger than those in COD regions. For long-wave (LW) radiative forcing, the no-dust cloud (CLD) is around 102.8 W/m2 , which is 20% less than the LW forcing from COD regions. The instantaneous TOA net radiative forcing for the CLD region is about - 208.2 W/m2, which is 42.1 % larger than the values of COD regions. The existence of dust aerosols under clouds significantly reduces the cooling effect of clouds.

关键词： dust storm cloud radiative forcing global warming dust aerosol-cloud-climate interaction.

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Effects of sunspot cycle length and CO_2 on air temperature along Qinghai-Xizang railway and air temperature's trend prediction

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science china Earth sciences 2004年第z1期47卷 131-141页

作者： LI Dongliang, QUO Hui, WANG Wen & WEI LiCold & Arid Regions Environmental and Engineering Research Institute, Chinese Academy of science, lanzhou 730000, china Department of atmospheric sciences, lanzhou university, lanzhou 730000, china Cold & Arid Regions Environmental and Engineering Research Institute Chinese Academy of Science Lanzhou China Department of atmospheric sciences Lanzhou University Lanzhou China

There are well coherences between annual averaged air temperatures at every meteorological station along the Qinghai-Xizang railway, and its 10-year moving average correlation coefficient is 0.92. Thus, the regional averaged annual mean temperature series along the Qinghai-Xizang railway (Trw) from 1935 to 2000 are constructed. The investigation is suggested that: Trw had significant responses to the 5-year lagged sunspot cycle length (SCL) and 15-year lagged concentration of atmospheric carbon dioxide (CO2), and the correlation coefficients between them are -0.76 (SCL) and 0.88 (CO2), respectively. The future SCL is predicted by the model of average generated function constructed with its main cycles of 76a, 93a, 108a, 205a and 275a. The result shows that the SCL would be becoming longer in the first half of the 21st century, and then it could be becoming shorter in the second half of the 21st century. Based on the natural change of SCL and the effect of double CO2 concentration, Trw in the 21st century is forecasted. It could warm up about 0.50℃ in the first half of the 21st century compared with the last decade of last century. The mean maximum air temperature could be likely about 0.20℃ in July and from 0.40℃ to 1.10℃ in January. The annual air temperature difference would likely reduce 0.3-1.00℃. The probability of above predictions ranges from 0.64 to 0.73.

关键词： Qinghai-Xizang railway, annual mean air temperature, sunspot cycle length (SCL), atmospheric carbon dioxide concentration (CO2), prediction.

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Comparison of sensible and latent heat fluxes during the transition season over the western Tibetan Plateau from reanalysis datasets

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Progress in Natural science:Materials International 2009年第6期19卷 719-726页

作者： Yang Cui, Chenghai Wang Disaster Reduction Key Laboratory of Gansu Province, college of atmospheric sciences, lanzhou university, lanzhou 730000, china Disaster Reduction Key Laboratory of Gansu Province College of Atmospheric Sciences Lanzhou University Lanzhou 730000 China

The sensible and latent heat fluxes during the transition season over the western Tibetan Plateau from the NCEP-1 (NCEP/NCAR Reanalysis 1), AR-Ⅱ (NCEP-DOE Reanalysis 2) and ERA40 reanalysis datasets were compared and analyzed. The results show that the phase change in soil moisture has a significant effect on the sensible and latent heat fluxes over the western Tibetan Plateau (TP) due to the freezing-thawing processes during the transition from the dry to the wet period. The uncertainties in the sensible and latent heat fluxes over the western TP are quite high in the reanalysis data, and depend largely on the success of the soil moisture simulations in the models. Improving the hydrological process simulations in the land-surface models in seasonally frozen ground and in the active frozen soil layer may be an effective way of enhancing the reliability of the surface heat fluxes from the reanalysis data over the Tibetan Plateau.

关键词： Western Tibetan Plateau Surface heat fluxes Reanalysis data Transition season Freezing-thawing process

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Strengthening of the boreal winter Hadley circulation and its connection with ENSO

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Progress in Natural science:Materials International 2007年第11期17卷 1327-1333页

作者： Ma Jie1,2 and Li Jianping2(1. college of atmospheric sciences, lanzhou university, lanzhou 730000, china 2. LASG, Institute of atmospheric Physics, Chinese Academy of sciences, Beijing 100029, china) college of atmospheric sciences Lanzhou University Lanzhou 730000 China

Empirical orthogonal function (EOF) analysis is carried out for the year-to-year variability of the boreal winter (DJF) mass stream function of the mean meridional circulation (MMC) during the period 1948—2005. The results demonstrate that it is dominated by the equatorially asymmetric and symmetric modes. Further analysis shows that the former mode is linked with the boreal winter Hadley cell mainly on the decadal time-scale, and the latter on the interannual time-scale. The asymmetric mode index (AMI) with a clear upward trend contributes to the decadal strengthening of the boreal Hadley circulation, and is closely correlated with the tropical SST warming, especially in the region of Indo-west Pacific warm pool (INWP). Furthermore, the AMI also contributes to the abrupt change of the correlation coefficient between the boreal Hadley circulation and ENSO after 1976. The symmetric mode index (SMI) with robust and stable linkage with ENSO shows a significant interannual variability, suggesting that the variability of the Hadley circulation is mainly associated with ENSO on the interannual time-scale.

关键词： the Hadley circulation interannual time-scale decadal time-scale

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A piecewise-integration method for simulating the influence of external forcing on climate

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Progress in Natural science:Materials International 2008年第10期18卷 1239-1247页

作者： Zhifu Zhang Chongjian Qiu Chenghai Wang Key Laboratory of Arid Climatic Changing and Reducing Disaster of Gansu Province,college of atmospheric sciences,lanzhou university.lanzhou 730000.china Key Laboratory of Arid Climatic Changing and Reducing Disaster of Gansu Province College of Atmospheric Sciences Lanzhou University Lanzhou 730000 China

Climate drift occurs in most general circulation models (GCMs) as a result of incomplete physical and numerical representation of the complex climate system,which may cause large uncertainty in sensitivity experiments evaluating climate response to changes in external *** solve this problem,we propose a piecewise-integration method to reduce the systematic error in climate sensitivity studies. The observations are firstly assimilated into a numerical model by using the dynamic relaxation technique to relax to the current state of atmosphere,and then the assimilated fields are continuously used to reinitialize the simulation to reduce the error of climate simulation. When the numerical model is integrated with changed external forcing,the results can be split into two parts,background and pertur- bation fields,and the background is the state before the external forcing is *** piecewise-integration method is used to con- tinuously reinitialize the model with the assimilated field,instead of the ***,the simulation error of the model with the external forcing can be *** this way,the accuracy of climate sensitivity experiments is greatly *** with a simple low-order spectral model show that this approach can significantly reduce the uncertainty of climate sensitivity experiments.

关键词： Climate model External forcing Sensitivity experiment Low-order spectral model Dynamic relaxation technique

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Computational stability of the forced dissipative nonlinear atmospheric equations

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Chinese science Bulletin 1999年第10期44卷 949-952页

作者： LI Jianping and CHOU Jifan LASG , Institute of atmospheric Physics , Chinese Academy of sciences , Beijing 100080, china Department of atmospheric sciences , lanzhou university , lanzhou 730000, china Beijing Meteorological college, Beijing 100081, china LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Department of atmospheric sciences Lanzhou University Lanzhou China Beijing Meteorological college Beijing China

A new concept of computational quasi-stability (CQS) is introduced to study the computational stability (CS) of the forced dissipative nonlinear (FDN) evolution equations. Based on the concept, the CQS criterion of difference scheme of FDN atmospheric equations is obtained. So it provides the theoretical basis for designing the computational stable difference scheme of FDN atmospheric equations.

关键词： computational stability (CS) computational quasi-stability (CQS) operator equation difference scheme forced dissipative nonlinear (FDN) equations.

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Development of a Chinese land data assimilation system:its progress and prospects

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Progress in Natural science:Materials International 2007年第8期17卷 881-892页

作者： Li Xin~(1**) Huang Chunlin~1 Che Tao~1 Jin Rui~1 Wang Shugong~l Wang Jiemin~1 Gao Feng~1 Zhang Shuwen~2 Qiu Chongjian~2 Wang Chenghai~2 (1.Cold and Arid Regions Environmental and Engineering Research Institute,Chinese Academy of sciences,lanzhou 730000,china 2.college of atmospheric sciences,lanzhou university,lanzhou 730000,china) Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

The objective of land data assimilation is to merge multi-source observations into the dynamics of land surface model for improving the estimation of land surface *** have developed a land data assimilation system for china's land *** this sys- tem,the Common Land Model and Simple Biosphere Model 2 are used to simulate land surface *** radiative transfer models of thawed and frozen soil,snow,lake,and vegetation are used as observation operators to transfer model predictions into estimated bright- ness temperatures.A Monte-Carlo based sequential filter,the ensemble Kalman filter,is implemented as data assimilation method to inte- grate modeling and *** system is capable of assimilating passive microwave remotely sensed data such as special sensor mi- crowave/imager (SSM/I),TRMM microwave imager (TMI),and advanced microwave scanning radiometer enhanced for EOS (AMSR- E) and the conventional in situ measurements of soil and snow.A spatiotemporally consistent assimilated dataset for soil moisture,soil temperature,snow and frozen soil,with a spatial resolution of 0.25 degree and temporal resolution of one hour,has been *** paper introduces the development of Chinese land data assimilation system and the progress made on data assimilation algorithms,land sur- face modeling,microwave remote sensing of land surface hydrological variables,and the preparation of atmospheric forcing *** dis- tinct characteristics and challenges of developing land data assimilation system and the perspectives for future development are also dis- cussed.

关键词： land data assimilation land surface model passive microwave remote sensing Kalman filter

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Characteristics and origins of primary fluids and noble gases in mantle-derived minerals from the Yishu area,Shandong Province,china

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science china Earth sciences 2006年第1期49卷 77-87页

作者： MA Jinlong1,2, TAO Mingxin2,3 & YE Xianren2 1. Resources and Environmental School, lanzhou university, lanzhou 730000, china 2. Key Laboratory of Gas Geochemistry, Institute of Geology and Geophysics, Chinese Academy of sciences, lanzhou 730000, china 3. college of Resources science & Technology, Beijing Normal university, Beijing 100875, china Resources and Environmental School Lanzhou University Lanzhou China Key Laboratory of Gas Geochemistry Institute of Geology and Geophysics Chinese Academy of Sciences Lanzhou China college of Resources science & Technology Beijing Normal University Beijing China

Fluids and noble gases of mantle-derived materials are important tracers forthe mantle information. Compositions of primary fluids and noble gases in mantle-derived mineralsfrom the Yishu area, Shandong Province, china, were tested by the methods of heat-bursting andheat-melting respectively. The fluids are mainly composed of CO_2, CO and H_2, which account forabout 90% of the total, and are similar to the mantle-derived rocks from other areas of easternchina; ratios of ~3He/~4He in almost all samples range from 0.82 Ra to 2.74 Ra, whereas^(40)Ar/^(36)Ar from 299.5 to 758.8. Both ranges are much lower than those of the typical oceanmantle-derived samples (such as MORB) and primarily reflect the influences of the atmosphericcomponents and the radiogenic isotopes. Ratios of C/~3He range from 27.6 x 10~9 to 1050 x 10~9,N_2/Ar from 927 to 56612, and N_2/~3He from 2.5 x 10~9 to 27 x 10~9, similar to those in westernUnited States and New Zealand which belong to the tectonic plate collision regions. The ratios fallin the intersect of mantle-crust-atmosphere in the comprehensive tracer-charts, reflecting theinfluences of the atmosphere and the crusts with organic components. Our results suggest that thecomposition of the primary fluids and the isotopic ratios of the noble gases may either reflect theevolution process of mantle-derived rocks connected with the rise and eruption of magma, or theinfluence of the ancient subduction-plate on the continental mantle of this region.

关键词： noble gases, primary fluids, mantle-derived minerals, Yishu area.

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Three-dimensional decomposition method of global atmospheric circulation

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science china Earth sciences 2008年第3期51卷 386-402页

作者： LIU HaiTao1,2,3, HU ShuJuan4, XU Ming5 & CHOU JiFan6,7 1 State Key Laboratory of Numerical Modeling for atmospheric sciences and Geophysical Fluid Dynamics, Institute of atmospheric Physics, Chinese Academy of sciences, Beijing 100029, china 2 Graduate university of Chinese Academy of sciences, Beijing 100049, china 3 Beijing Climate Center, Beijing 100089, china 4 Department of Mathematics, lanzhou university, lanzhou 730000, china 5 Shanghai Typhoon Institute, Shanghai 200030, china 6 Department of atmospheric sciences, lanzhou university, lanzhou 730000, china 7 china Meteorological Administration Training Center, Beijing 100089, 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 Beijing Climate Center Beijing China Department of Mathematics Lanzhou University Lanzhou China Shanghai Typhoon Institute Shanghai China Department of atmospheric sciences Lanzhou University Lanzhou China china Meteorological Administration Training Center Beijing China

By adopting the idea of three-dimensional Walker, Hadley and Rossby stream functions, the global atmospheric circulation can be considered as the sum of three stream functions from a global perspective. Therefore, a m... 详细信息

关键词： three-dimensional decomposition of the global atmospheric circulation generalized Walker Hadley and Rossby stream functions existence and uniqueness vertical motion

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