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reconstructing mean maximum temperature of growing season from the maximum density of the Schrenk Spruce in Yili,Xinjiang,china

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Chinese Science Bulletin 2009年第13期54卷 2300-2308页

To study the historical temperature variation in Yili of Xinjiang,the tree-ring chronologies of maximum density(MXD) and tree-ring width(TrW) were established with the Schrenk Spruce(Picea schrenkiana *** Mey) collected from six sites to analyze the characteristics and ability of response to climate *** results suggest that the MXD chronology of the Schrenk Spruce from different sampling sites responded to climate change well and were positively correlated with the mean maximum temperature and the mean temperature from April to August in the study *** mean maximum temperature anomaly from April to August,spanning the years from 1848 to 2000,was reconstructed by three MXD chronologies which were selected by stepwise *** reconstructed function was stable and explained 56.2% of the *** reconstructed results indicated a cold span of 153 years in spring and summer from the beginning of the 1950s to the beginning of the 1970s in the Yili *** strongly increasing tendency was detected in the mean maximum temperature anomaly from April to August during this reconstructed period.

关键词：平均最高气温伊犁谷地最大密度云杉胡杨生长季节新疆树木年轮宽度

Growth characteristics and response to climate change of Larix Miller tree-ring in china

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Science china Earth Sciences 2010年第6期53卷 871-879页

As one of the earliest species used in dendrochronological studies, Larix responds sensitively to climate change. In this study, nine larch species and one variety from eleven sites were collected to study the growth characteristics of tree-ring width using dendrochronological methods. Ten residual tree-ring chronologies were developed to analyze their relationships with regional standardized anomaly series by Pearson’s correlation analysis. The results suggest that most of the chronologies had significantly positive correlations with the mean temperature and mean maximum temperature in May. The spring temperature evidently limited the radial growth of the larch species without precipitation control. The largest mean tree-ring width was found in Himalayan Larch in Jilong, whereas Master Larch in Si’er reflected the smallest mean value. Both species presented little climate information in this study. Chinese, Potanin, and Tibetan larches are significantly correlated with climate change, implying a huge potential for climate history reconstruction. The elevation of the sampling sites appears to be an important condition for tree-ring growth of larches responding to climate factors.

关键词： Larix Miller tree-ring climate change mean temperature in May

Variations of Snow Temperature and their Influence on Snow Cover Physical Parameters in the Western Tianshan Mountains,china

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Journal of Mountain Science 2011年第6期8卷 827-837页

作者： CHEN Xia WEI WenShou LIU MingZhe GU GuangQin Xinjiang institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China Hebei Key Laboratory for meteorology and Eco-environmen Shijiazhuang 050021 China HeBei Climate Center Shijiazhuang 050021 China institute of desert meteorology China Meteorological Administration Urumqi 830011 China Tianshan Station for Snow-cover and Avalanche research Chinese Academy of Sciences Urumqi 830011 China

This article discussed about snow temperature variations and their impact on snow cover parameters. Automatic temperature recorders were used to sample at lo-minute intervals at the Tianshan Station for Snow-cover and Avalanche research, Chinese snow temperature Academy of Sciences. lo-layer and the snow cover parameters were measured by the snow property analyzer （Snow Fork） in its Stable period, Interim period and Snow melting period. results indicate that the amplitude of the diurnal fluctuation in the temperature during Snow melting period is 1.62 times greater than that during Stable period. Time up to the peak temperature at the snow surface lags behind the peak solar radiation by more than 2.5 hours, and lags behind the peak atmospheric temperature by more than 0.2 hours during all three periods. The optimal fitted function of snow temperature profile becomes more complicated from Stable period to Snow melting period. 22 h temperature profiles in Stable period are the optimal fitted by cubic polynomial equation. In Interim period and Snow melting period, temperature profiles are optimal fitted by exponential equation between sunset and sunrise, and by Fourier function when solar radiation is strong. The vertical gradient in the snow temperature reaches its maximum value at the snow surface for three periods. The peak of this maximum value occurs during Stableperiod, and is 4.46 times greater than during Interim period. The absolute value of temperature gradient is lower than 0.1℃ cm-1 for 30 cm beneath snow surface. Snow temperature and temperature gradient in Stable period-Interim period indirectly cause increase （decrease） of snow density mainly by increasing （decreasing） permittivity. While it dramatically increases its water content to change its permittivity and snow density in Snow melting period.

关键词： Snow temperature Vertical temperaturegradient Optimal fitting function Snow density Western Tianshan Mountains china

An Examination of Boundary Layer Structure under the Influence of the Gap Winds in Urumqi,china,during Air Pollution Episode in Winter

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An Examination of Boundary Layer Structure under the Influen...

On the sand surface stability in the southern part of Gurbantünggüt desert

强化科技基础推进气象现代化——第29届中国气象学会年会

作者： Xia Li institute of desert meteorology,Urumqi,china meteorology administration,china LAGEO,institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing,china Mailing address:No.46,Jianguo road,Urumqi,Xinjiang,china,830002 Xiangao Xia LAGEO,institute of Atmospheric Physics,Chinese Academy of Sciences,Beijing,china Yu Xin Xinjiang Climatic Center,Urumqi,china Yufen Ma institute of desert meteorology,Urumqi,china meteorology administration,china Jing Yang Xinjiang meteorological Science and Technological Service Center Jinglin Li Xinjiang Information Center of Developing Agriculture Network,Urumqi,china Xinghua Yang institute of desert meteorology,Urumqi,china meteorology administration,china

Tethered-sonde measurements of atmospheric profiles were performed at Urumuqi,capital of the Xinjiang Uyghur Autonomous region of china,from 29 December 2008 to 14 January *** data were used to examine the boundary layer structure during this severe air pollution *** evolution of local wind flow near Urumqi was simulated using the fifth-generation Pennsylvania State University-NCAr Mesoscale Model(MM5).Measurements from Operational radiosonde data showed that a southeasterly elevated low-level jet often intruded upon Urumqi through the middle Tianshan Mountain pass to the south of the *** tethered-sonde measurements showed that calm and northwesterly winds prevailed near the surface in Urumqi,while the southeasterly winds of relatively higher speed were dominant above 00 *** temperature inversion and humidity inversion frequently occur during day and *** inversion intensity could sharply rise as the stronger elevated southeasterly gales(ESEGs) *** simulations showed that the winds near the surface around Urumqi remained calm during nighttime and developed toward the mountains during *** cool air flow in the basin confronted the southeasterly winds from the pass in the lower layer,they formed a convergence line around Urumqi city,which was not favor for dilution of air pollutants.

关键词： middle Tianshan Mountain pass gap wind elevated southeasterly gale (ESEG) tethered-sonde severe air pollution episodes

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中国科学：地球科学英文版 2005年第6期48卷 778-785页

作者： WANG Xueqin1,2, WANG Tao1, JIANG Jin2 & ZHAO Congju2 1. Laboratory of Blown Sand Physics and desert Environment, Cold and Arid regions of Environmental and Engineering research In-stitute, Chinese Academy of Sciences, Lanzhou 730000, china 2. Xinjiang institute of Ecology and Geography, Chinese Academy of Sciences, Urmqi 830011, china Correspondence should be addressed to Wang Xueqin Laboratory of Blown Sand Physics and desert Environment Cold and Arid Regions of Environmental and Engineering Research In-stitute Chinese Academy of Sciences Lanzhou China Xinjiang institute of Ecology and Geography Chinese Academy of Sciences Urümqi China

Longitudinal dunes are the most widespread dune types in the world sand seas but comprehensive study on the sand surface stability is scarce. The southern part of Gurbantnggt desert is mainly covered by longitudinal dune in which fixed and semi-fixed dunes occupy over 80% of the total area. Systematic analysis on the climatic conditions, the soil moisture and vegetation distributions, and the sand surface activities showed that the fixed and semi-fixed dunes are in a comprehensive low-energy wind environment. Snow cover and frozen soil provide a good protection to the ground surface in winter. The temporal distribution of precipitation and corresponding variation of temperature create a favorable condition for the desert plants growth, especially for the ephemeral plants. The occurrence of effective winds for sand moving in April to June coincides with the stage of relatively wet sand surface and good vegetation cover, which effectively keep the sand surface stable at the interdune and the plinth of the dunes. Activity sand surface appears only at the crest and the upper part of the sand dunes.

关键词： Gurbantünggüt desert, longitudinal dune, sand surface stability.

Evolution of desertification in a two-dimensional energy balance model coupled with thermodynamics and dynamics

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Science china Earth Sciences 2010年第11期53卷 1726-1733页

作者： CHAO JiPing1,2 & LI YaoKun3,4 1National Marine Environmental Forecasting Center, Beijing 100081, china 2First institute of Oceanography, State Oceanic administration, Qingdao 266061, china 3State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics, institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, china 4Graduate University of Chinese Academy of Sciences, Beijing 100049, china National Marine Environmental Forecasting Center Beijing China First institute of Oceanography State Oceanic Administration Qingdao 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

The relationship between desert evolution and change in albedo has been investigated quasi-analytically using a zonal mean two-dimensional energy balance model which considers the radiation transmission process due to thermodynamics and bound- ary layer movement caused by kinetics. A climate state including temperature, zonal wind, meridional wind and vertical wind can be simulated according to the current zonal distribution of albedo. Given desert distribution, characterized by the value and distribution of albedo, the response of climate on albedo has been studied to analyze the evolution of desert climate. One significant result is that the simple model can reproduce mean meridional circulation. Another result indicates that climate corresponds to two equilibria. This happens when the junction temperature between vegetation and desert is higher than a certain critical value. As for the first equilibrium, the desert belt is predicted to move southward in the northern hemisphere with the increasing values of albedo, which corresponds to the current trend of climate change. For the second equilibrium, vegetation will expand northward with increasing values of albedo, which would indicate a narrowing of the desert belt. In order to determine if the two equilibria exist, new physical models are needed.

关键词： two-dimensional energy balance model desertification two equilibria

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三工河流域40年来气温、降水变化特征分析

水土保持研究 2005年第6期12卷 54-57页

作者：刘新春杨金龙杨青中国气象局乌鲁木齐沙漠气象研究所乌鲁木齐830002 新疆大学资源与环境科学学院乌鲁木齐830046

分析了三工河流域40 a来气温、降水变化的基本特征,所得的主要结果如下:(1)阜康、天池的气温和降水的变化有线性增加的趋势,气候由暖干向暖湿转变。(2)阜康、天池各季平均气温的变幅以冬季最大,夏季最小;各季的降水以夏季最大,冬季最小... 详细信息

分析了三工河流域40 a来气温、降水变化的基本特征,所得的主要结果如下:(1)阜康、天池的气温和降水的变化有线性增加的趋势,气候由暖干向暖湿转变。(2)阜康、天池各季平均气温的变幅以冬季最大,夏季最小;各季的降水以夏季最大,冬季最小,总体趋势是温度升高、降水增多。(3)自60年代来气温基本上呈上升趋势,每年代增幅都在0.3℃以上;降水没有气温变化明显,但降水量在增加。(4)阜康的气温和降水分别具有5.0年左右和3.3年左右的周期;天池的气温具有2.7年左右的主周期和8年左右的次周期,降水则存在2.9年左右的主周期和4.4年左右的次周期。

关键词：气温降水气候变化三工河流域

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东亚沙尘分布、源汇及输送特征的模拟研究

中国环境科学 2017年第3期37卷 801-812页

作者：郭俊银燕王咏薇康汉青肖辉陈魁郝囝南京信息工程大学中国气象局气溶胶与云降水重点开放实验室江苏南京210044 江苏省气候中心江苏南京210008 南京信息工程大学气象灾害预报预警与评估协同创新中心江苏南京210044 中国气象局广州热带海洋气象研究所广东广州510080

采用全球气溶胶模式(GOCArT)模拟结果,讨论了东亚地区沙尘气溶胶时空分布、排放与沉降以及区域输送特征.结果表明,中国境内沙源主要位于塔克拉玛干沙漠、河西走廊及河套地区.排放强度春季最大,夏季和秋季逐渐减小,冬季最弱,且强度逐年减... 详细信息

采用全球气溶胶模式(GOCArT)模拟结果,讨论了东亚地区沙尘气溶胶时空分布、排放与沉降以及区域输送特征.结果表明,中国境内沙源主要位于塔克拉玛干沙漠、河西走廊及河套地区.排放强度春季最大,夏季和秋季逐渐减小,冬季最弱,且强度逐年减弱,区域年平均排放为581Tg/a.模拟的沙尘光学厚度(AOD)分布与卫星观测具有很好的一致性,其中塔克拉玛干沙漠AOD大值与沙尘暴活动密切相关,其出现时间最早,持续时间最长.区域平均而言,干沉降和湿沉降可以分别清除77%和22%的沙尘排放,其中沙尘源区干沉降起主导作用,远离源区的东北及西北太平洋,湿沉降更加重要.沙尘大粒子主要通过重力干沉降移出,而湿沉降对小粒子贡献超过60%.重力干沉降全年(特别是春季)起主导作用,对流降水湿沉降在夏季作用显著增强,总体来说,沙尘总沉降速率逐年减小.东亚沙尘气溶胶通过3条输送带自西向东传输,可以影响我国华北、华中和华南.对散度的研究表明,气溶胶平流项对沙尘源区气溶胶辐散作用较大,沙尘排放显著影响该地区沙尘的输送和AOD;而塔里木盆地西侧沙尘辐合中心是风场辐合辐散项导致的,说明地形和风场对该地区沙尘输送和AOD很重要.

关键词：沙尘气溶胶起沙量分布干湿沉降输送

特克斯河流域近236a降水变化及其趋势预测

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山地学报 2010年第5期28卷 545-551页

作者：陈峰袁玉江魏文寿喻树龙范子昂张瑞波张同文尚华明中国气象局乌鲁木齐沙漠气象研究所中国气象局树木年轮理化研究重点实验室新疆维吾尔自治区树木年轮生态重点实验室

根据2006年采自特克斯河流域6个采样点的树轮样本研制的树轮宽度年表与气象资料,通过相关普查发现,特克斯河流域树轮标准化年表与上年7月至当年6月的降水存在显著的正相关,最高单相关系数为0.727。用库尔克尔也灭,小白代的树轮宽度标准... 详细信息

根据2006年采自特克斯河流域6个采样点的树轮样本研制的树轮宽度年表与气象资料,通过相关普查发现,特克斯河流域树轮标准化年表与上年7月至当年6月的降水存在显著的正相关,最高单相关系数为0.727。用库尔克尔也灭,小白代的树轮宽度标准化年表序列,可较好地重建该地区最近236a的降水序列,方差解释量达54%,并通过交叉检验表明重建结果是稳定可靠的。近236a,特克斯河流域上年7月至当年6月降水经历了8个偏湿阶段和8个偏干阶段,同时重建降水序列具有10.3a、7.5a、6.0a、3.0a、2.1a的变化准周期,并在1790年,1911年,1929年,1974年发生过降水突变。采用毛毛虫-奇异谱分析法(Caterpillar-ssa)对该地区未来20a的降水的自然变化进行预测。结果表明,21世纪的最初几年降水量将延续20世纪90年代以来增加的趋势,之后出现下降,并在2013~2016年前后最低值出现。

关键词：特克斯河流域树轮年表降水变化趋势预测