GCM Simulations of Stable Isotopes in the Water Cycle in Comparison with GNIP Observations over East Asia   总被引：1，自引：0，他引：1       下载免费PDF全文

ZHANG Xinping  SUN Zhian  GUAN Huade  ZHANG Xinzhu  Wu Huawu  Huang Yimin 《Acta Meteorologica Sinica》2012,26(4):420-437

In this paper, we examine the performance of four isotope incorporated GCMs, i.e., ECHAM4 (University of Hamburg), HadCM3 (Hadley Centre), GISS E (Goddard Institute of Space Sciences), and MUGCM (Melbourne University), by comparing the model results with GNIP (Global Network of Isotopes in Precipitation) observations. The spatial distributions of mean annual δD and mean annual deuterium excess d in precipitation, and the relationship between δ18 o and δD in precipitation, are compared between GCMs and GNIP data over East Asia. Overall, the four GCMs reproduce major characteristics of δD in precipitation as observed by GNIP. Among the four models, the results of ECHAM4 and GISS E are more consistent with GNIP observed precipitation δD distribution. The simulated d distributions are less consistent with the GNIP results. This may indicate that kinetic fractionation processes are not appropriately represented in the isotopic schemes of GCMs. The GCM modeled MWL (meteoric water line) slopes are close to the GNIP derived MWL, but the simulated MWL intercepts are significantly overestimated. This supports that the four isotope incorporated GCMs may not represent the kinetic fractionation processes well. In term of LMWLs (local meteoric water lines), the simulated LMWL slopes are similar to those from GNIP observations, but slightly overestimated for most locations. Overall, ECHAM4 has better capability in simulating MWL and LMWLs, followed by GISS E. Some isotopic functions (especially those related to kinetic fractionation) and their parameterizations in GCMs may have caused the discrepancy between the simulated and GNIP observed results. Future work is recommended to improve isotopic function parameterization on the basis of the high-resolution isotope observations.  相似文献   

Spatiotemporal distributions of δD in atmospheric water vapor based on TES Data during 2004–2009          下载免费PDF全文

章新平  张新主  关华德  黄一民  吴华武 《Acta Meteorologica Sinica》2012,26(6):683-699

The spatial and temporal distributions of the stable isotopes such as HD¹⁶O (or ¹H²H¹⁶O, or HDO) and H₂ ¹⁸O in atmospheric water vapor are related to evaporation in source places, vapor condensation during transport, and vapor convergence and divergence, and thus provide useful information for investigation and understanding of the global water cycle. This paper analyzes spatiotemporal variations of the content of isotope HDO (i.e., δ _D), in atmospheric water vapor, namely, δ _{D v}, and the relationship of δ _{D v} with atmospheric humidity and temperature at different levels in the troposphere, using the HDO and H₂O data retrieved from the Tropospheric Emission Spectrometer (TES) at seven pressure levels from 825 to 100 hPa. The results indicate that δ _{D v} has a clear zonal distribution in the troposphere and a good correspondence with atmospheric precipitable water. The results also show that δ _{D v} decreases logarithmically with atmospheric pressure and presents a decreasing trend from the equator to high latitudes and from lands to oceans. Seasonal changes of δ _{D v} exhibit regional differences. The spatial distribution and seasonal variation of δ _{D v} in the low troposphere are consistent with those in the middle troposphere, but opposite situations occur from the upper troposphere to the lower stratosphere. The correlation between δ _{D v} and temperature has a similar distribution pattern to the correlation between δ _{D v} and precipitable water in the troposphere. The stable isotope HDO in water vapor (δ _{D v}), compared with that in precipitation (δ _{D p}), is of some differences in spatial distribution and seasonal variation, and in its relationship with temperature and humidity, indicating that the impacts of stable isotopic fractionation and atmospheric circulation on the two types of stable isotopes are different.  相似文献   

Air–sea interaction and formation of the Asian summer monsoon onset vortex over the Bay of Bengal     

Guoxiong Wu  Yue Guan  Yimin Liu  Jinghui Yan  Jiangyu Mao 《Climate Dynamics》2012,38(1-2):261-279

In spring over the southern Bay of Bengal (BOB), a vortex commonly develops, followed by the Asian summer monsoon onset. An analysis of relevant data and a case study reveals that the BOB monsoon onset vortex is formed as a consequence of air–sea interaction over BOB, which is modulated by Tibetan Plateau forcing and the land–sea thermal contrast over the South Asian area during the spring season. Tibetan Plateau forcing in spring generates a prevailing cold northwesterly over India in the lower troposphere. Strong surface sensible heating is then released, forming a prominent surface cyclone with a strong southwesterly along the coastal ocean in northwestern BOB. This southwesterly induces a local offshore current and upwelling, resulting in cold sea surface temperatures (SSTs). The southwesterly, together with the near-equatorial westerly, also results in a surface anticyclone with descending air over most of BOB and a cyclone with ascending air over the southern part of BOB. In the eastern part of central BOB, where sky is clear, surface wind is weak, and ocean mixed layer is shallow, intense solar radiation and low energy loss due to weak surface latent and sensible heat fluxes act onto a thin ocean layer, resulting in the development of a unique BOB warm pool in spring. Near the surface, water vapor is transferred from northern BOB and other regions to southeastern BOB, where surface sensible heating is relatively high. The atmospheric available potential energy is generated and converted to kinetic energy, thereby resulting in vortex formation. The vortex then intensifies and moves northward, where SST is higher and surface sensible heating is stronger. Meanwhile, the zonal-mean kinetic energy is converted to eddy kinetic energy in the area east of the vortex, and the vortex turns eastward. Eventually, southwesterly sweeps over eastern BOB and merges with the subtropical westerly, leading to the onset of the Asian summer monsoon.  相似文献   

近30年京津冀地区冰雹的气候特征和突变分析   总被引：7，自引：0，他引：7  

闵晶晶  曹晓钟  段宇辉  刘还珠  王式功 《气象》2012,38(2):189-196

基于1979—2008年京津冀地区175个气象站的冰雹观测资料,应用气候趋势系数、倾向率、集中度和集中期,以及连续功率谱等方法,分析了京津冀地区及4个划分关键区冰雹发生的多时间尺度变化特征和变化趋势,并运用蒙特卡罗方法检验了气候趋势系数的显著性。结果表明：近30年该地区的冰雹有明显减少趋势,北部地区比南部地区减少幅度要大,山地区域比平原地区减少幅度大;基本上都存在2.0～2.5年的变化周期,该地区冰雹的发生具有准两年周期振荡的特征;南部平原冰雹发生的集中度最大,该区冰雹在年内发生时间最为集中;南部平原集中期较早,出现在6月初,其他几个关键区冰雹主要发生在6月底到7月初。应用气候要素累计距平曲线、Yamamoto方法进行了气候突变分析,结果表明京津冀地区冰雹在1993年发生了减少的突变,山地区域尤为显著。  相似文献   

1988-2009年全球地面风速变化趋势研究   总被引：1，自引：0，他引：1  

郑崇伟  李思祥  王冠  仇晓庆 《气象与环境科学》2012,35(Z1)

利用来自ESE的1988-2009年高精度、高分辨率的CCMP风场资料,对全球0.25°×0.25°每个网格点上地面风速的逐年变化趋势进行分析.研究发现:近22 a期间,全球大部分区域的地面风速以显著性递增趋势为主导,递增趋势较强的区域主要分布于南极大陆的临海区域、格陵兰岛的临海区域;显著性逐年线性递减以及地面风速无明显变化趋势的区域主要散布于全球各地的一些零星区域,且不同地区地面风速的变化趋势由不同季节主导.  相似文献   

台风“榴莲”陆上维持及暴雨增幅的大尺度环流特征   总被引：1，自引：1，他引：0  

王黎娟  卢珊  管兆勇  何洁琳 《气候与环境研究》2010,15(4):511-521

利用"CMA-STI热带气旋最佳路径集"、NCEP/NCAR再分析资料及地面加密观测资料,分析了2001年0103号台风"榴莲"陆上维持及暴雨增幅的大尺度环流特征。结果表明,"榴莲"登陆后正好位于低压带中,中纬度西风槽加强南伸,构成典型的"北槽南涡",阻碍西太平洋副热带高压西伸,使得"榴莲"陆上长时间维持。西风槽后的西北气流将中纬度冷空气输送至低纬,在"榴莲"环流北部外围与东南风暖湿气流汇合,有利于强降水发生。此外,索马里和100°E越赤道气流增强显著,加强西南季风,从阿拉伯海东部,经孟加拉湾和中南半岛中南部,直至南海北部到广西大部形成一条完整的水汽输送带,充沛的水汽直达"榴莲"东北侧,有利于该时段暴雨增幅。低纬夏季风10～20天低频振荡处于极端活跃位相时,低纬低频西风偏北及低频水汽向北输送至广西南部,有利于低层辐合并提供充足水汽,对"榴莲"暴雨增幅有重要作用。  相似文献   

厦门汽车产业集群创新网络结构与功能研究     

陈玉慧  汪欣彤  郑孟玲 《地域研究与开发》2012,31(1):60-64,98

在知识经济时代,创新是时代的特征,产业集群只有创新才能承受升级的压力,才具有发展的活力;不具备创新能力、无法及时升级的产业集群最终将面临被市场淘汰的命运,而这些追根究底就是集群创新机制的构建问题,集中表现为集群创新网络的构建.从优势企业角度出发,探讨厦门汽车产业基于大金龙集群创新网络的结构和功能.研究发现:虽然以大金龙为核心的厦门汽车产业集群创新网络已经具备雏形,并显现出集聚创新资源、自学习、自增强的功能,但是各个主体之间的联系还不紧密,集群创新网络的其他功能也尚未得到充分发挥.改革现有企业制度,加强主体间的合作联系,将有助于集群网络发挥其他功能.  相似文献   

Intercomparison of stable isotopes in precipitation simulated by GCMs with GNIP survey over East Asia     

XinPing Zhang  ZhiAn Sun  HuaDe Guan  XinZhu Zhang 《寒旱区科学》2012,4(4):0330-0341

Using the isotope enabled ECHAM4, GISS E and HadCM3 GCMs, the spatial distribution of mean δ¹⁸O in precipitation, mean seasonality and the correlations of δ¹⁸O in precipitation with temperature and precipitation amount are analyzed. The simulated results are in agreement with stable isotopic features by GNIP observations. Over East Asia, the distribution of δ¹⁸O in precipitation is of marked latitude effect and altitude effect. The latitude effect is covered by the continent effect in some regions. The largest seasonality of δ¹⁸O in precipitation appears in eastern Siberia controlled by cold high pressure, and the smallest seasonality is in the western Pacific controlled by the subtropical high. Relatively weak seasonality appears in middle latitudes where oceanic and continental air masses frequently interact. However, three GCMs show significant systematic lower δ¹⁸O for inland mid-high latitudes than GNIP data, which is related to the used isotopic scheme in GCMs. Temperature effect occurs mainly in inland mid-high latitudes. The higher the latitude and the closer the distance to inland is, then the stronger the temperature effect. Amount effect occurs mainly in low-mid latitudes and monsoon areas, with the strongest effect in low-latitude coasts or islands. However, three GCMs provide virtually non-existent amount effect in arid regions over Central Asia. The enrichment action of stable isotopes in falling raindrops under a cloud base, which is enlarged by these modes, is responsible for such a result. A significant difference between spatial distributions of δ¹⁸O statistics by GCMs simulations and by GNIP observations is that the standard deviation of GCMs statistics is greater than that of GNIP statistics. In contrast, by comparing parallel time series at a single station, the standard deviations of GCMs simulations are smaller than that of GNIP observations.  相似文献   

成都市近地表大气尘铅分布特征及源解析   总被引：7，自引：1，他引：7  

尚英男  杨波  尹观  倪师军  张成江 《物探与化探》2006,30(2):104-107

分析了成都市近地表大气尘样品铅及其同位素含量比的测定数据,铅含量变化范围为(119.76～1327.42)×10^-6,均值为374.51×10^-6,统计标准偏差为273.36,变异系数为0.73,说明成都市近地表大气尘铅含量变化大。燃煤飞灰的放射性成因铅明显高于汽油和柴油,可作为鉴别大气尘铅来源的证据。铅同位素含量数据表明成都市近地表大气尘的铅污染是复合污染源所致,其中,相对清洁区污染以建筑扬尘为主,中度污染区是汽车尾气和扬尘的叠加作用,重污染区是燃煤飞灰汽车尾气和工业污染源的综合表征。  相似文献   

河南省桐柏县银洞坡金矿床同位素地球化学   总被引：11，自引：10，他引：11  

张静  陈衍景  陈华勇万守全张冠王建明 《岩石学报》2006,22(10):2551-2560

银洞坡金矿床位于河南肖桐柏地区围山城金银多金属矿带内,矿体定位受新元古界歪头山组地层控制。各成矿阶段热液石英中流体的δ~(18)O_w值为0.0‰～10.8‰,晚期碳酸盐中流体的δ~(18)O_W 值为-5.3‰～-9.7‰,流体的δD值为-65‰～-84‰,显示早阶段成矿流体以来自赋矿地层的变质水为主,晚阶段大气降水不断混入。包裹体的δ~(13)C_(CO)_2值介于-3.7‰～ 6.7‰,指示流体的碳主体来自碳酸盐储库。硫化物的δ~(34)S 值介于 1.3‰～ 3.1‰,具塔式分布特征,硫主要源自围岩歪头山组。~(206)Pb/~(204)Pb=16.540～17.216,~(207)Ph/~(204)Pb=15.056～15.612,~(208)Pb/~(204)Pb=37.336～38.861,显示较明显的铀铅亏损特征,矿石铅ω值介于39.50～48.62,显示铅源的物质成熟度高,为赋矿地层歪头山组,矿石铅同位素与歪头山组地层的一致性及其与南、北秦岭其它构造岩石单元的差异表明,银洞坡金矿的成矿物质主要来自歪头山组地层。无论在成矿流体和物质来源方面,还是在矿床地质特征方面,银洞坡金矿都应属于典型的层控造山型金矿,并形成于扬子与华北大陆板块的碰撞体制。  相似文献