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Nonlinear interactions between gravity waves and background winds

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Progress in Natural Science:Materials International 2007年第6期17卷 639-644页

作者： Liu Xiao1,2 and Xu Jiyao1(1. State Key Laboratory for Space Weather, center for Space Science and Applied Research, chinese academy of sciences, beijing 100080, china 2. Graduate University of chinese academy of sciences, beijing 100039, china) [a]State Key Laboratory for Space Weather Center for Space Science and Applied Research Chinese Academy of Sciences Beijing China [b]Graduate University of chinese academy of sciences Beijing China

Using the nonlinear propagating gravity waves (GW) model in the two-dimensional compressible atmosphere and the linear GW theory, the process of GW propagation in different background winds, e.g. the direction of the background wind is opposite to (dead wind) or the same as (tail wind) the direction of the horizontal phase velocity of GW, is studied. The results show that the dead wind prolongs the vertical wavelength and accelerates GW propagation. Therefore, GW propagates up to a higher height becomes instable in a short time and eventually induces an inverse jet flow. Then, the vertical wavelength is becoming short due to the nonlinear interactions between GW and the inverse jet flow. The vertical wavelength and group velocity decrease after GW propagates into the tail wind. The initial instable time is delayed. Although most of GW is trapped in the instable region, some of GW propagates above the instable region. Compared with GW propagation in the tail wind, the nonlinear interactions between GW and the dead wind are also strong. In contrast, the linear GW theory predicts that GW can propagate freely in the dead wind. The vertical wavelength simulated by the nonlinear numerical model is different from that predicted by the linear theory greatly after GW propagates into the dead wind.

关键词： gravity waves background winds vertical group velocity vertical wavelength nonlinear interactions.

chinese HJ-1A/B satellites and data characteristics

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中国科学：地球科学英文版 2010年第S1期53卷 51-57页

作者： WANG Qiao1,WU ChuanQing1,LI Qing1 & LI JunSheng2 1 Satellite Environment center,Ministry of Environmental Protection,beijing 100029,china 2.center for Earth Observation and Digital Earth,chinese academy of sciences,beijing 100190,china 1. Satellite Environment center Ministry of Environmental Protection Beijing 100029 China2. Center for Earth Observation and Digital Earth Chinese Academy of Sciences Beijing 100190 China

From the viewpoint of environmental remote-sensing applications,this article explains the overall technical characteristics of the chinese HJ-1A and HJ-1B *** also investigates the spectral characteristics and potential applications of charge-coupled devices,and the infrared and hyperspectral data obtained by the *** of applications,such as the remote-sensing monitoring of algal bloom in Taihu Lake,straw burning in southern china,and aerosol optical depth in the area around Bohai sea are *** examples illustrate the application characteristics of the HJ-1A and HJ-1B satellite data.

关键词： HJ-1A/B application remote sensing characteristics

Biologically effective radiation of solar ultraviolet radiation and the depletion of stratospheric ozone

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Journal of Environmental sciences 1994年第3期6卷 373-381页

作者： Wang Shaobin Su Weihan(Research center for Eco-Environmental sciences,chinese academy of sciences),beijing 100085,china) Wei Dingwen(institute of Atmospheric Physics,chinese academy or sciences),beijing 100029,china)

Based on the biological action spectra and total UV-B radiation in the atmosphere,the effective UV-dose for DNA, erythema,and plant at different seasons in the last decade,and their future change in beijing area were *** results indicate that the maxi- mum of biologically effective radiation dose at noontime is in July and the minimum is in January. From 1980 to 1989 biologically effective radiation dose have increased with the average rates of about 0.6,0.7 and 1.1 mW/m￣2 per year for January, April and October,while in July the trend of radiation dose is not ln evidence. For 1% reduction of ozone concentration radiation amplification factor for DNA,erythema and plant are 2.3,2.3 and 1.4 and for 30% reduction of ozone concentration the RAF for DNA,erythema and plant are 4.2,4.0 and 2.1,respectively.

关键词： UV-B ozone depletion biological effects solar radiation.

Some characteristics of the atmosphere during an adiabatic process

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Progress in Natural Science:Materials International 2006年第6期16卷 644-648页

作者： GAO Li, LI Jianping and REN Hongli (LASG, institute of Atmospheric Physics, chinese academy of sciences, beijing 100029, china Graduate School of chinese academy of sciences, beijing 100049, china National Climate center, Laboratory of Climate Studies, china Meteorological Administration, beijing 100081, china) [a]LASG Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China [b]Graduate School of chinese academy of sciences Beijing China [c]National Climate center Laboratory of Climatic Studies China Meterological Administration Beijing China

Some important characteristics of the atmosphere during an adiabatic process are investigated, which include the invariability of atmospheric entropy range and local surface potential temperature, the conservation of the atmospheric mass intervened between any isentropic surface and the ground, and the isentropic surface intersecting with the ground. The analysis shows that the atmospheric reference state (ARS) for investigation on available potential energy (APE) should be defined objectively as the state which could be approached from the existing atmosphere by adiabatic adjustment, and be related to initial atmospheric state before adjustment. For the initial atmosphere state at any time, its corresponding ARS is different from the one at another time. Based on the above-mentioned conclusions, the reference state proposed by Lorenz cannot be obtained physically, so a new conception, the conditional minimum total potential energy, is put forward in order to objectively investigate atmospheric APE.

关键词： available potential energy adiabatic isentropic surface atmospheric reference state conditional minimum total potential energy.

De-interlacing technique based on total variation with spatial-temporal smoothness constraint

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Science in china(Series F) 2007年第4期50卷 561-575页

作者： YIN XueMin1,2,3, YUAN JianHua1,2, LU XiaoPeng1,2 & ZOU MouYan1,2 1 institute of Electronics, chinese academy of sciences, beijing 100080, china 2 Graduate School, chinese academy of sciences, beijing 100039, china 3 Jiuquan Satellite Launch center, Lanzhou 732750, china 1. institute of Electronics Chinese Academy of Sciences Beijing 100080 China 2. Graduate School Chinese Academy of Sciences Beijing 100039 China 3. Jiuquan Satellite Launch center Lanzhou 732750 China

This paper introduces a new method of converting interlaced video to a progressively scanned video and image, The new method is derived from Bayesian framework with the spatial-temporal smoothness constraint and the MAP is done by minimizing the energy functional, The half-quadratic regularization method is used to solve the corresponding partial differential equations （PDEs）, This approach gives the improved results over the conventional de-interlacing methods, Two criteria are proposed in the paper, and they can be used to evaluate the performance of the de-interlacing algorithms,

关键词： video processing de-interlacing total variation spatio-temporai smoothness constraint PDEs half-quadratic regularization

Modeling the climate effects of different subregional uplifts within the Himalaya-Tibetan Plateau on Asian summer monsoon evolution

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chinese Science Bulletin 2012年第35期57卷 4617-4626页

作者： ZHANG Ran 1,JIANG DaBang 1,2,3,LIU XiaoDong 4 & TIAN ZhiPing 2,5 1 Climate Change Research center,chinese academy of sciences,beijing 100029,china 2 Nansen-Zhu International Research Centre,institute of Atmospheric Physics,chinese academy of sciences,beijing 100029,china 3 Key Laboratory of Regional Climate-Environment Research for Temperate East Asia,chinese academy of sciences,beijing 100029,china 4 State Key Laboratory of Loess and Quaternary Geology,institute of Earth Environment,chinese academy of sciences,Xi’an 710075,china 5 Graduate University of chinese academy of sciences,beijing 100049,china 1. Climate Change Research center Chinese Academy of Sciences Beijing 100029 China 2. Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China 3. Key Laboratory of Regional Climate-Environment Research for Temperate East Asia Chinese Academy of Sciences Beijing 100029 China 4. State Key Laboratory of Loess and Quaternary Geology Institute of Earth Environment Chinese Academy of Sciences Xi’an 710075 China 5. Graduate University of chinese academy of sciences Beijing 100049 China

Considering the different uplifting time of different subregions of the Himalaya-Tibetan Plateau(TP),a series of numerical simulations have been conducted with the Community Atmosphere Model(CAM4) developed at the National center for Atmospheric Research to explore the effects of the phased tectonic uplift of the Himalaya-TP on the evolution of Asian summer *** results show that the uplifts of the Himalaya and northern TP significantly affect the evolutions of South Asian summer monsoon and northern East Asian summer monsoon *** is,the tectonic uplift of the Himalaya intensifies the South Asian summer monsoon circulation and increases the precipitation in South Asia,whereas the uplift of the northern TP intensifies the northern East Asian summer monsoon circulation and increases the precipitation in northern East *** with previous simulations,current comparative analyses of modeling results for different subregional uplifts within the Himalaya-TP help deepen our understanding of the evolutionary history of Asian monsoons.

关键词：青藏高原隆升喜马拉雅亚洲季风高原气候夏季季风次区域隆起演化建模

NEW WIND WAVE GROWTH RELATIONS

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Journal of Hydrodynamics 2004年第5期16卷 608-614页

作者： WUShu-ping HOUYi-jun YINBao-shu instituteofOceanology ChineseAcademyofSciencesQingdao266071China

In the present paper combining the relationship between wave steepness andwave age with the significant wave energy balance equation for wind wave, a new wind wave growthrelation is presented. Comparisons with the other existing wind wave growth relations show that theresults in present paper accord better with the wind wave growth process.

关键词： relationship between wave steepness and wave age wind wave energy balanceequation new wind wave growth relation

A tool model for predicting atmospheric chemical kinetics with sensitivity analysis

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Journal of Environmental sciences 2001年第1期13卷 79-86页

作者： SHEN Ji (Research center for Eco\|Environmental sciences, chinese academy of sciences, beijing 100085, china.E\|mail:shenji@***) Research center for Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 China. shenji@***

A package(a tool model) for program of predicting atmospheric chemical kinetics with sensitivity analysis is presented. The new direct method of calculating the first order sensitivity coefficients using sparse matrix technology to chemical kinetics is included in the tool model, it is only necessary to triangularize the matrix related to the Jacobian matrix of the model equation. The Gear type procedure is used to integrate a model equation and its coupled auxiliary sensitivity coefficient equations. The FORTRAN subroutines of the model equation, the sensitivity coefficient equations, and their Jacobian analytical expressions are generated automatically from a chemical mechanism. The kinetic representation for the model equation and its sensitivity coefficient equations, and their Jacobian matrix is presented. Various FORTRAN subroutines in packages, such as SLODE, modified MA28, Gear package, with which the program runs in conjunction are recommended. The photo\|oxidation of dimethyl disulfide is used for illustration.

关键词： atmospheric chemical model chemical kinetics sensitivity analysis

Comparison of degradation reactions of Acid Yellow 61 in both oxidation processes of H_2O_2/UV and O_3

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Journal of Environmental sciences 2001年第3期13卷 304-310页

作者： WANG Yi zhong 1, A.Yedeler 2, A. Kettrup 2(1 Research center for Eco Environmental sciences, chinese academy of sciences, beijing 100085, china 2 GSF institute of Ecological Chemistry, Neuherberg, Postfach 1129, 85758 Neuherberg, Germany) Research center for Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 China.

The comparison of degradation of Acid Yellow 61 as a model dye compound in both oxidation processes of H 2O 2/UV and O 3 has been studied. When the decolorization rate of Acid Yellow 61 in both reactions presented similar, it was found there are some differences from the results of AOX removal and production of inorganic ions and organic acids. The results reveal that the H 2O 2/UV has beneficial effect on mineralization than O 3 only for degradation of Acid Yellow 61 solution and it is possible for enhancement of method efficiency by taking longer reaction time and addition of high concentration of oxidants.

关键词： oxidation process H 2O 2/UV O 3 dye compound