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Effects of 4DVAR with multifold observed data on the typhoon track forecast

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Chinese Science Bulletin 2003年第S2期48卷 93-98页

作者： WANG Yunfeng, WANG Bin, MA gaNG & WANG Yushun 1. LASG, institute of atmospheric Physics, Chinese Academy of {2.. Beijing 10002., China: 2. National Satellite Meteorological Center, Beijing 100081. China Chinese Acad Sci Inst Atmospher Phys LASG Beijing 100029 Peoples R China Natl Satellite Meteorol Ctr Beijing 100081 Peoples R China

Effects of 4-dimension variational data assimi-lation (4DVAR) with multifold observed data on the typhoontrack forecast are studied, by using the MM5V3 model, theRTTOVS-5 model and their adjoint models. The data usedfor assimilation include large-scale background fields data,bogus data, cloud-derived wind data, satellite inverse data,and high resolution infrared radiation sounder data (HIRS).There are 5 typhoon cases are used to perform the numericalexperiments and assimilation experiments. The numericalresults show that with 4DVAR the initial fields can be greatlyimproved and the initial typhoon structure can be clearlydescribed.

关键词： multifold observed data 4DVAR typhoon track. DOI: 10.1360/03wd0456

Sea-salt aerosol transport patterns over the Northern Hemisphere inferred from two subarctic ice core records

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Science China Earth sciences 2005年第4期48卷 576-584页

作者： YAN Yuping1,2. KANG Shichang2.3,5, SUN Junying4,5, Paul A. Mayewski2.& QIN Dahe5 1. National Climate Center, China Meteorological Administration, Beijing 100081, China 2. Climate Change institute, University of Maine, Orono, ME 04469, usa 3. institute of Tibetan Plateau Research, Chinese Academy of sciences, Beijing 100085, China 4. Chinese Academy of Meteorological sciences, Beijing 100081, China 5. Key Laboratory of Ice Core and Cold Regions Environment, Cold and Arid Environmental and Engineering Research institute, Chinese Academy of sciences, Lanzhou 730000, China National Climate Center China Meteorological Administration Beijing China Climate Change institute University of Maine Orono ME USA institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing China Key Laboratory of Ice Core and Cold Regions Environment Cold and Arid Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China Chinese Academy of Meteorological sciences Beijing China

atmospheric circulation reconstruction based on glaciochemical records requires knowledge of chemical concentration controls, such as source, transport pathway and strength. To gain insight into these processes, the relationships between glaciochemical records from two Northern Hemisphere sites (Mt. Logan in Yukon Territory and 2.D in southern Greenland) and instrumental sea level pressure (SLP) series are investigated. Calibrations between Mt. Logan sea-salt sodium (ssNa+) concentration and SLP series show that ssNa+ concentrations are closely correlated with the autumntime (SON) Aleutian Low and the summertime (JJA) North Pacific Subtropical High. Both the deepened Aleutian Low and enhanced North Pacific Sub- tropical High strengthen the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. Calibrations between 2.D ssNa+ concentrations and SLP series indicate that ssNa+ concentrations are closely related to the wintertime (Jan.) Icelandic Low. A deepening of the Icelandic Low strengthens winter storms and frequent cyclogenesis over the North Atlantic and pushes more sea-salt laden air masses to the Greenland ice sheet. Therefore, ice core ssNa+ records from the Mt. Logan region can be considered as a proxy for reconstructing the au- tumntime Aleutian Low and summertime North Pacific Subtropical High, and the ssNa+ records from Greenland ice core (2.D) may provide a proxy for reconstructing the wintertime Icelandic Low.

关键词： sea-salt aerosol, ice core records, sea level pressure, subarctic regions.

Study on the atmospheric photochemical reaction of CF_3 radicals using ultraviolet photoelectron and photoionization mass spectrometer

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Science China Chemistry 2008年第4期51卷 316-321页

作者： YAO Li1,2. DU Lin1,2. YIN Shi1,2.& GE MaoFa1 1 Beijing National Laboratory for Molecular sciences (BNLMS), State Key Laboratory for Structural Chemistry of Unstable and Stable Species, institute of Chemistry, Chinese Academy of sciences, Beijing 100080, China 2.Graduate University of Chinese Academy of sciences, Beijing 100080, China Beijing National Laboratory for Molecular sciences (BNLMS) State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing China Graduate University of Chinese Academy of sciences Beijing China

A study of the atmospheric photochemical reaction of CF3 radical with CO and O2.was performed by using a homemade ultraviolet photoelectron spectrometer-photoionization mass spectrometer (PES- PIMS). The electronic structures and mechanism of ionization and dissociation of CF3OC(O)OOC(O)- OCF3 were investigated. It was indicated that the two bands on the photoelectron spectrum of CF3OC(O)OOC(O)OCF3 are the result of ionization of an electron from a lone pair of oxygen and a fluo- rine lone pair of CF3 group. The outermost electrons reside in the oxygen lone pair. The experimental and theoretical first vertical ionization energy is 13.2. and 13.178 eV, respectively, with the PES and OVGF method. They are in good agreement. The photo ionization and dissociation processes were discussed with the help of theoretical calculations and PES-PIMS experiment. After ionization, the parent ions prefer the dissociation of the C-O bond and giving the fragments CF3OCO+ and CF3+. It demonstrated that the ultraviolet photoelectron and photoionization mass spectrometer could be ap- plied widely in the study of atmospheric photochemical reaction.

关键词： photochemical reaction CF3 radical ultraviolet photoelectron and photoionization mass spectroscopy transient species

Simulation Experiments of Land Surface Physical Processes and Ecological Effect over Different Underlying Surface

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地球科学进展 2004年第S1期19卷 15-20页

作者： LIU Shu-hua~(1,2., JIANG Hao-yu, HU Fei~2.LIU Hui-zhi~2.LIANG Fu-ming~1, WANG Jiang-hua~1(1. Group of Atmosphere Boundary Layer and turbulence, Ministry Laboratory of Storm and Drought Flood Damage, Department of atmospheric sciences the {2. of Physics Peking University, Beijing 100871, China 2. State Key Laboratories of Atmosphere Physics and Chemistry, institute of atmospheric Physics, Chinese Academy of Science, Beijing 10002., China)

Based on the existing Land Surface Physical Process Models(Deardorff, Dickinson, LIU, Noilhan, Seller, ZHAO), a Comprehensive Land Surface Physical Process Model (CLSPPM) is developed by considering the different physical processes of the earth's surface-vegetation-atmosphere system more completely. Compared with SiB and BATS, which are famous for their detailed parameterizations of physical variables, this simplified model is more convenient and saves much more computation time. Though simple, the feas...

关键词： Comprehensive land surface Physical process model (CLSPPM) Simulation experiment Land surface physical process Ecological effect.

Response synchronization: New progress in brain-visual information processing

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Chinese Science Bulletin 1999年第16期44卷 1447-1458页

作者： ZHAO Songnian, XIONG Xiaoyun, YAO Guozheng and GUO Aike1. State Key Laboratory of atmospheric Boundary Layer Physics and atmospheric Chemistry , {2. of atmospheric Physics , Chinese Academy of sciences , Beijing 10002., China 2. Commission of the National Natural Science Foundation of China , Beijing 100083, China 3. The Center of Information Science , Peking University, Beijing 100871, China 4. Open Laboratory of Visual Information Processing , {2. of Biophysics , Chinese Academy of sciences , Beijing 100101, China State Key Laboratory of atmospheric Boundary Layer Physics and atmospheric Chemistry Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Commission of the National Natural Science Foundation of China Beijing China The Center of Information Science Peking University Beijing China Open Laboratory of Visual Information Processing Institute of Biophysics Chinese Academy of Sciences Beijing China

Studies on brain-vision have entered a new stage, after the stimulus-induced y synchronized oscillation of neuron group activities have been discovered in cat primary visual cortex. Naturally, how to understand the visual system became a very important methodological problem. From aspects such as information processing, nonlinear dynamics and neuronal network, some primary problems in vision studies have been deeply discussed, which are

关键词： neuron group (neural population) synchro-oscillation computational theory of vision response synchroniza-tion.

Summer Arctic sea fog

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Acta Oceanologica Sinica 2001年第2期20卷 183-196页

作者： Xie Simei, Xue Zhenhe, Jiang Dezhong, Zou Bin, Qu Shaohou (1. National Research Center for Marine Environment Forecasts, Beijing 100081, China 2. institute of atmospheric Physics, Chinese Academy of {2., Beijing 10002., China) Natl. Res. Ctr. for Marine Envrn. Fo Beijing 100081 China

Synchronous or quasi-synchronous sea-land-air observations were conducted using advanced sea ice, atmospheric and marine instruments during China's First Arctic Expedition. *** on the Precious data from the expedition, it was found that in the Arctic Ocean, most part of which is covered with ice or is mixed with ice, various kinds of sea fog formed such as advection fog, radiation fog and vapor fog. Each kind he its own characteristic and mechanics of creation. In the southern part of the Arctic Ocean, due to the sufficient warm and wet flow there, it is favorable for advection fog to form, which is dense and lasts a long time. On ice cap or vast floating ice, due to the strong radiation cooling effect, stable radiating fog is likely to form. In floating ice area there forms vapor fog with the appearance of masses of vapor from a boiling pot, which is different from short-lasting land fog. The study indicates that the reason why there are many kinds of sea fog form in the Arctic Ocean is because of the complicated cushion and the consequent sea-air interaction caused by the sea ice distribution and its unique physical characteristics. Sea fog is the atmospheric phenomenon of sea-air heat exchange. Especially, due to the high albedo of ice and snow surface, it is diffcult to absorb great amount of solar radiation during the polar days. Besides, ice is a poor conductor of heat; it blocks the sea-air heat exchange. The sea-air exchange is active in floating ice area where the ice is broken. The sea sends heat to the atmosphere in form of latent heat; vapor fog is a way of sea-air heat exchange influencing the climate and an indicator of the extent of the exchange. The study also indicates that the sea also transports heat to the atmosophere in form of sensible heat when vapor fog occurs.

关键词： Arctic sea fog vapor fog radiation fog advection fog mechanism of the creation of sea fog

Existence of the solutions and the attractors for the large-scale atmospheric equations

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Science China Earth sciences 2006年第6期49卷 650-660页

作者： HUANG Haiyang1 & GUO Boling2.1. Department of Mathematics, Beijing Normal University, Beijing 100875, China 2. institute of Applied Physics and Computational Mathematics, Beijing 100080, China Department of Mathematics Beijing Normal University Beijing China institute of Applied Physics and Computational Mathematics Beijing China

In this paper, firstly, the proper function space is chosen, and the proper expression of the operators is introduced such that the complex large-scale atmospheric motion equations can be described by a simple and abstract equation, by which the definition of the weak solution of the atmospheric equations is made. Secondly, the existence of the weak solution for the atmospheric equations and the steady state equations is proved by using the galerkin method. The existence of the non-empty global attractors for the atmospheric equations in the sense of the Chepyzhov-Vishik’s definition is obtained by constructing a trajectory attractor set of the atmospheric motion equations. The result obtained here is the foundation for studying the topological structure and the dynamical behavior of the atmosphere attractors. Moreover, the methods used here are also valid for studying the other atmospheric motion models.

关键词： atmosphere equations, weak solution, trajectory attractor, global attractor, equilibrium.

Simulation of soil erosion dynamics in grassland ecosystem of semi-arid China using the CENTURY model

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Journal of Geographical sciences 2000年第3期10卷 81-86页

作者： ZHANG Jia-hua1, FU Cong-bin 1 ,YAO Feng-mei 2.(1. START, institute of atmospheric Physics, Chinese Academy of {2., Beijing, 10002. China 2. Beijing Forestry University, Beijing 100083, China)

Soil erosion can cause considerable effect on global natural resources and eco-environment. In the paper, the CENTURY model has been used to simulate soil erosion in Xilin Gol Grassland of Inner Mongolia. The results showed before the 1960s, the soil erosion amount was over 2.kg /m2.a in grassland ecosystem in the study area because no trees had been planted. But after the 1960s the mean annual accumulator C lost from soil organic matter due to soil erosion was only 0.3 kg /m2.a in forest ecosystem. So afforestation has exerted notable effect on decreasing soil erosion amount in Xilin Gol Grassland.

关键词： soil erosion CENTURY model grassland ecosystem semi-arid environment

Interannual and Interdecadal Variability of atmospheric Water Vapor Transport in the Haihe River Basin

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Pedosphere 2005年第5期15卷 585-594页

作者： WEI Jie LIN Zhao-Hui XIA Jun TAO Shi-Yan institute of atmospheric Physics Chinese Academy of Sciences Beijing 100029 （China） institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100044（China）

The seasonal mean atmospheric precipitable water and water vapor transport over the Haihe River Basin （HRB） in North China with a focus on their interannual to interdecadal variability, and then the relationships of the interannual and interdecadal variability of the water cycle over the HRB to the Pacific Decadal Oscillation （PDO） and E1 Nino-Southern Oscillation （ENSO） phenomena were investigated using the observational and National Centers for Environmental Prediction （NCEP） reanalysis data. There was a strong interdecadal variability for the water cycle （such as precipitation and water vapor transport） over the region, with an abrupt change occurring mostly in the mid 1970s. The intensity of the East Asian summer monsoon largely affected the atmospheric water vapor transport. Generally, the net meridional convergence of the water vapor flux over the region was relatively large before 1965, and it declined gradually from then on with a further notable decrease since mid 1970s. Zonal water vapor transport was similar to meridional, but with a much smaller magnitude and no noteworthy turning in the mid 1970s. Results also suggested that the wind field played an important role in the water vapor transport over the HRB before the mid 1960s, and the interdecadal variability of the water cycle （precipitation, water vapor transport, etc.） in the summer was related to the PDO; however, interannual variation of the water vapor transport could also be related to the ENSO phenomena.

关键词： interannual variability interdecadal variability Haihe River Basin water vapor transport