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Turbulent intensity and its similarity function over an Inner Mongolian grassland during spring

Science china Earth sciences 2010年第5期53卷 773-780页

作者： YUE Ping1,2,3, NIU ShengJie2, HU YinQiao4 & ZHANG Qiang1 1 Key Laboratory of arid Climate Change and Reducing Disaster of Gansu Province, Key Laboratory of arid Climate Change and Reducing Disaster of CMA, institute.of arid Meteorology, CMA, lanzhou 730020, china 2 Nanjing University of Information Science and Technology, Nanjing 210044, china 3 Zhangye National Meteorological Observatory, Zhangye 734000, china 4 cold and arid regions environmental and engineering research institute. chinese academy of Science, lanzhou 730000. china Key Laboratory of arid Climate Change and Reducing Disaster of Gansu Province Key Laboratory of Arid Climate Change and Reducing Disaster of CMA Institute of Arid Meteorology CMA Lanzhou China Nanjing University of Information Science and Technology Nanjing China Zhangye National Meteorological Observatory Zhangye China cold and arid regions environmental and engineering research institute Chinese Academy of Science Lanzhou China

Macroscopic reason for the development of turbulences in fluid is the conjunction action of velocity and temperature shears. We use the 2008 spring flux observations in the surface layer over Inner Mongolian grassland, obtain the similarity functions of turbulent intensity under different stratification stability conditions, and calculate the clear day turbulent intensity in the spring, which is then analyzed and compared with the observed values of turbulent intensity. The results show that in the Inner Mongolian grassland, under the condition of spring unstable stratification of the surface layer, dependence of the similarity function of turbulent intensity on stratification stability follows a "2/3 power law". The structural function is a constant under the neutral stratification condition, and complicated under the stable condition. The calculated turbulent intensity has a close correlation with the observed one, which verifies the accuracy of the similarity functions and the suitability of the theorem of turbulent intensity in the grassland region.

关键词： turbulent intensity variance of velocity similarity function grassland

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Ice Surface-Elevation Change and Velocity of Qingbingtan Glacier No.72 in the Tomor region,Tianshan Mountains,Central Asia

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Journal of Mountain Science 2011年第6期8卷 855-864页

作者： WANG Puyu LI Zhongqin LI Huilin WANG Wenbin WANG Feiteng College of Geography and environment Science Northwest Normal University Lanzhou 730070 China State Key Laboratory of Cryospheric sciences Cold and Arid Region Environment and Engineering Research Institute/Tianshan Glaciological Station Chinese Academy of Sciences Lanzhou 730000 China

Glaciers in the Tomor region of Tianshan Mountains preserve vital water ***,these glaciers suffer from strong mass losses in the recent years because of global *** 2008 to 2009,a large-scale scientific expedition has been carried out in this *** an individual reference glacier,the tongue area of Qingbingtan glacier No.72 was measured by the high precise Real Time Kinematic-Global Position System (RTK-GPS).In this paper,changes of the tongue area of Qingbingtan glacier No.72 has been studied based on topographic map,remote sensing image and the survey during 2008-2009 field *** indicated that the ice surface-elevation of the tongue area changed-0.22±0.14 m a-1 from 1964 to *** estimated loss in ice volume was 0.014±0.009 km3,which represented a ～20 % decrease from the 1964 volume and was equivalent to average annual mass balance of-0.20±0.12 m water equivalent for the tongue area during *** retreated by 1852 m,approximately 41 m a-1,with the area reduction of 1.533 km2 (0.034 km2 a-1) from 1964 to ***,the annual velocity reached to ～70 m *** with the other monitored glaciers in the eastern Tianshan Mountains,Qingbingtan glacier No.72 experienced more intensive in shrinkage,which resulted from the combined effects of climate change and glacier dynamic,providing evidence of the response to climatic warming.

关键词：冰川面积高程变化冰面速度天山中亚全球定位系统质量损失

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Using lightning locating system based on time-of-arrival technique to study three-dimensional lightning discharge processes

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Science china Earth sciences 2010年第4期53卷 591-602页

作者： ZHANG GuangShu1,WANG YanHui1,QIE XiuShu2,ZHANG Tong1,ZHAO YuXiang1,3,LI YaJun1 & CAO DongJie11 Laboratory for Climate environment and Disasters of Western china,cold and arid regions environmental and engineering research institute.chinese academy of sciences,lanzhou 730000.china 2 Laboratory for Middle Atmosphere and Global environment Observation(LAGEO),institute.of Atmospheric Physics,chinese academy of sciences,Beijing 100029,china 3 Department of Physics,Tianshui Normal College,Tianshui 741001,china Laboratory for Climate environment and Disasters of Western china Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou China Laboratory for Middle Atmosphere and Global environment Observation (LAGEO) Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Department of Physics Tianshui Normal College Tianshui China

A time-of-arrival(TOA) system based on GPS technology for locating VHF radiation sources from lightning has been developed and used in observation sites in the northern Shandong Province,*** 3D images of the lightning progression have been obtained successfully for the first time in *** 3D-channel evolutions of typical negative CG,positive CG and IC lightning flashes have been discussed together with the data of fast electric field *** was found that significant differences existed between the negative and positive CG lightning flashes in terms of the initiation and propagation of the radiation *** preliminary breakdown of a negative CG lightning flash propagated at a speed about 5.2×104 m/*** stepped leader of negative CG lightning flashes was trigged by negative initial ***,it propagated downward at a speed of 1.3×105 m/*** initial process of the positive CG lightning flashes was also a propagation process of negative *** streamers propagated dominantly horizontally in the positive charge region and accumulated positive charges at the origin of the lightning,and as a consequence,initiated downward positive streamers.A new type of lightning discharge that was triggered by a narrow bipolar pulse(NBP) is discussed in this *** NBP was originated at altitude of about 10.5 km in the upper positive charge *** a distinct difference from normal IC flash,its channels extended horizontally all around and produced a lot of radiation *** source power of the NBP could approach 16.7 kW,which is much greater than that of normal lightning discharge ranging between 100 mW and 500 *** 3D propagation of this new type of lightning discharge was observed and obtained for the first time in *** possible initiation mechanism of this new type of light-ning is discussed here.

关键词： time-of-arrival(TOA) technique three dimensional lightning locating system discharge process narrow bipolar pulse new-type of IC lightning

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Identification and Evolution of Groundwater Chemistry in the Ejin Sub-Basin of the Heihe River, Northwest china

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Pedosphere 2007年第3期17卷 331-342页

作者： SU Yong-Hong FENG Qi ZHU Gao-Feng SI Jian-Hua ZHANG Yan-Wu cold and arid regions environmental and engineering research institute Chinese Academy of Sciences Lanzhou730000 （China） School of Mathematics and Statistics Lanzhou University Lanzhou 730000 （China）

Hydro-chemical characteristics of groundwater and their changes as affected by human activities were studied in the Ejin Sub-Basin of the Inner Mongolia Autonomous region, china, to understand the groundwater evolution, to identify the predominant geochemical processes taking place along the horizontal groundwater flow path, and to characterize anthropogenic factors affecting the groundwater environment based on previous data. The concentrations of major ions and total dissolved solids (TDS) in the groundwater showed a great variation, with 62.5% of the samples being brackish (TDS≥1000 mg L-1). The groundwater system showed a gradual hydro-chemical zonation composed of Na+-HCO3-, Na+-Mg2+-SO42-Cl-, and Na+-Cl-. The relationships among the dissolved species allowed identification of the origin of solutes and the processes that generated the observed water compositions. The dissolution of halite, dolomite, and gypsum explained, in part, the presence of Na+, K+, Cl-, SO42-, and Ca2+, but other processes, such as mixing, Na+ exchange for Ca2+ and Mg2+, and calcite precipitation also contributed to the composition of water. Human activity, in particular large-scale water resources development associated with dramatic population growth in the last 50 years, has led to tremendous changes in the groundwater regime, which reflected in surface water runoff change, decline of groundwater table and degeneration of surface water and groundwater quality. Solving these largely anthropogenic problems requires concerted, massive and long-term efforts.

关键词：西北地区黑河额济纳子流域地下水质量化学成分鉴定演变

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Effect of temperatures and moisture content on germination of Ammopiptanthus mongolica seeds

Effect of temperatures and moisture content on germination o...

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中国植物学会七十五周年年会

作者： Yi Li (Dunhuang Gobi and Desert Ecology and environment research Station,cold and arid region environmental and engineering research institute.chinese academy of sciences,lanzhou,730000.

The seed experiment with Ammopiptanthus mongolica was started in 2006 at lanzhou,china. Seeds of 4.67% and 3.73% moisture content(MC)were kept at 45,25 and 15℃ in hermetically sealed *** initial germination was 96.7%...

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A 290-a record of atmospheric circulation over the North Pacific from a Mt. Logan ice core, Yukon Territory

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Acta Oceanologica Sinica 2005年第4期24卷 81-90页

作者： KANG Shichang MAYEWSKI Paul A YAN Yuping institute.of Tibetan Plateau research Chinese Academy of Sciences Beijing 100085 China Climate Change institute University of Maine Orono ME 04469 USA Laboratory of Cryosphere and environment Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China National Climate Center Beijing 100081 China

Calibrations between sodium （Na^＋） concentrations from a Mt. Logan ice core and sea level pressure （SLP） series show that Na^＋ concentrations are closely correlated with the autumn-time （September-October-November） Aleutian low （AleuLow）. A deepening of the AleuLow strengthens the transport of sea-salt aerosols from the North Pacific to the Mt. Logan region. The Mt. Logan Na^＋ record is used to develop a 292 a （1688-1979） reconstruction of the AleuLow revealing a dramatic intensification of atmospheric circulation over the North Pacific region since the 20th century. Mean SLP of the AleuLow was about 1 hPa lower during the 20th century than during prior periods. The strongest deepening of the AleuLow appeared in the 1950s. Significant correlations are also found between the Mt. Logan AleuLow proxy series and the Pacific decadal oscillation （PDO） and Pacific circulation （PC） index during the 20th century. Evolutionary spectral analysis of the proxy record shows significant periodicities from 15 to 30 a consistent with PDO fluctuations and the bidecadal oscillation of North Pacific atmosphere-ocean circulation. A period of 11 a in the AleuLow record may be associated with the Schwabe 11-a cycle of sunspot activity. Additional longer ice core records from this region will aid in the efforts to further understand the climatic change over the North Pacific region.

关键词： atmospheric circulation ice core records North Pacific

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A new interpolation method for Antarctic surface temperature

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Progress in Natural Science:Materials International 2009年第12期19卷 1843-1849页

作者： Yetang Wang~(a,b),Shugui Hou~(b,c,*) a Monitoring Centre of Ocean environment of Shandong Province,Yantai 264006,china b State Key Laboratory of Cryospheric Science,cold and arid regions environmental and engineering research institute. chinese academy of sciences,lanzhou 73000,china c MOE,Key Laboratory for Coast and Island Development,School of Geographic and Oceanographic sciences,Nanjing University,Nanjing 210093,china Monitoring Centre of Ocean environment of Shandong Province Yantai 264006 China State Key Laboratory of Cryospheric Science Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 73000 China MOE Key Laboratory for Coast and Island Development School of Geographic and Oceanographic Sciences Nanjing University Nanjing 210093 China

We propose a new methodology for the spatial interpolation of annual mean temperature into a regular grid with a geographic resolution of 0.01°for Antarctica by applying a recent compilation of the Antarctic temperature data.A multiple linear regression model of the dependence of temperature on some geographic parameters(i.e.,latitude,longitude,and elevation) is proposed empirically,and the kriging method is used to determine the spatial distribution of regional and local deviations from the temperature calculated from the multiple linear regression *** modeled value and residual grids are combined to derive a high-resolution map of surface air temperature. The performance of our new methodology is superior to a variety of benchmark methods(e.g.,inverse distance weighting,kriging, and spline methods) via cross-validation *** simulation resembles well with those distinct spatial features of surface temperature,such as the decrease in annual mean surface temperature with increasing latitude and the distance away from the coast line; and it also reveals the complex topographic effects on the spatial distribution of surface temperature.

关键词： Surface temperature DEM Antarctica

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Simulation of oasis breeze circulation in the arid region of the Northwestern china

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Science china Earth sciences 2004年第Z1期47卷 101-107页

作者： LU Shihua, AN Xingqin & CHEN Yuchuncold and arid regions environmental and engineering research institute. chinese academy of sciences, lanzhou 730000. china cold and arid regions environmental and engineering research institute Chinese Academy of Sciences Lanzhou 730000 China

In this paper, the process of oasis-desert circulation (ODC) is simulated by MM5V3.5 model through designing an ideal oasis-desert scheme and assuming that initial atmosphere is at rest (V = 0). The findings showed that the key of forming special oasis boundary structure is the difference of energy and water between oasis and desert. The evaporation of oasis surface consumes heat energy, and the low temperature of oasis causes an oasis breeze circulation (OBC), which drives an ODC with a downdraft over the oasis and an updraft over the desert. Later, the cold, dry and stable boundary over oasis is gradually formed, on the contrary,the atmospheric boundary over desert on the edge of oasis is hot, humid and unstable and its height is about 600 hPa. The updraft over the desert forms a wet ring that acts as a vertical wall weakening the low-level moisture exchange between the oasis and desert. The downdraft of OBC increases the atmospheric stability that reduces the oasis evaporation. The low-level outflow from the oasis (into the desert) prevents the dry, hot air flowing from the desert into the *** an oasis self-preservation mechanism may be formed due to OBC. The horizontal area influenced by oasis is twice as oasis area and the vertical range is four times as oasis. The ODC is strong in the daytime and reaches the strongest at 17:00, and the influenced area is the largest at 20:00.

关键词： oasis atmospheric boundary layer numerical simulation.

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Modeling the Roles of Precipitation Increasing in Glacier Systems Responding to Climate Warming—Taking Xinjiang Glaciated region as Example

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Journal of Mountain Science 2005年第4期2卷 306-312页

作者： WANG Xin XIE Zichu LIU Shiyin TAO Jianjun HAN Yongshun YANG Yuelong research institute.of Geo-spatial Information Science Hunan University of Science ＆ Technology Xiangtan 411201 Hunan China Key Laboratory of Ice Core and cold region＇s environment Cold and Arid Regions Environmental and Engineering Research Institute CAS Lanzhou 730000 China institute.of Resources and environment Hunan Normal University Changsha 410081 China institute.of Tibetan Plateau research CAS Beijing 100029 China

The studies on prediction of climate in Xinjiang almost show that the precipitation would increase in the coming 50 years, although there were surely some uncertainties in precipitation predictions. On the basis of the structure of glacier system and nature of equilibrium line altitude at steady state (ELA0), a functional model of the glacier system responding to climate changes was established, and itsimultaneously involved the rising of summer mean temperature and increasing of mean precipitation. The results from the functional model under the climatic scenarios with temperature increasing rates of 0.01, 0.03 and 0.05 K/year indicated that the precipitation increasing would play an evident role in glacier system responding to climate change: if temperature become 1℃ higher, the precipitation would be increased by 10 %, which can slow down the glaciers retreating rate in the area by 4 %, accelerate runoff increasing rate by 8 % and depress the ELA0rising gradient by 24 m in northern Xinjiang glacier system where semi-continental glaciers dominate, while it has corresponding values of only 1 %, 5 % and 18m respectively in southern Xinjiang glacier system, where extremely continental glaciers dominate.

关键词：气候变暖冰川新疆气候变化

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Meteorological Features at 6523 m of ***(Everest)between 1 May and 22 July 2005

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Journal of Mountain Science 2006年第3期3卷 181-190页

作者： XIE Aihong REN Jiawen QIN Xiang JIANG Youyan Joint Key Laboratory of Cryosphere and environment Cold and Arid Regions Environment and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Mt. Qomolangma (Everest), the highest mountain peak in the world, has little been studied extensively from a meteorological perspective, mostly because of the remoteness of the region and the re-sultant lack of meteorological data. An automatic weather station (AWS), the highest in the world, was set up on 27 April 2005 at the Ruopula Pass (6523 m asl) on the northern slope of Mt. Qomolangma by the team of integrated scientific expedition to Mt. Qomo-langma. Here its meteorological characteristics were analyzed according to the 10-minute-averaged and 24-hour records of air temperature, relative humidity, air pressure and wind from 1 May to 22 July 2005. It is shown that at 6523 m of Mt. Qomolangma, these meteorological elements display very obvious diurnal variations, and the character of averaged diurnal variation is one-peak-and-one-vale for air tem-perature, one-vale for relative humidity, two-peak-and- two-vale for air pressure, and one-peak with day-night asymmetry for wind speed. In the 83 days, all the air temperature, relative hu-midity and air pressure increased with some dif-ferent fluctuations, while wind speed decreased gradually and wind direction turned from north to south. The variations of relative humidity had great fluctuations and obvious local differences. Then thepaper discusses the reason for the characters of diurnal and daily variations. Compared with the corresponding records in May 1960, 5-day-averaged maximums, minimums and diurnal variations of air temperature in May 2005 were apparently lower.

关键词：大气温度辐射相对湿度珠穆朗玛峰

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