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951.
INFLUENCE OF INTERACTION BETWEEN LOW AND MIDDLE LATITUDES ON ENSO VARIABILITY IN THE CANE-ZEBIAK MODEL*
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Ni Yunqi 《Acta Meteorologica Sinica》1996,10(2):160-174
In this paper,an error source in the atmospheric component of the CZ(Cane-Zebiak) model is discussed,which is missing a free mode in "the exact solutions".However,the improved scheme is proposed,which is the computational scheme with adjusted wind or observed u and v as lateral boundaries.The simulations show that the simulated surface wind by the improved scheme strongly bears resemblance to the observation except for the area near the west and the east boundaries of the integrated area.These results support the conclusion that the wind stress simulated by the improved scheme with lateral boundaries is much better than that simulated by the CZ model,and show that interaction between low and middle latitudes has an important influence on the ENSO variability in the CZ model.Therefore,considering its impact on the CZ model can improve capability of the CZ model for simulating ENSO variability. 相似文献
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不同地形下辐射收支各分量的差异与变化 总被引:12,自引:0,他引:12
给出了确定山区辐射收支各分量的方法,并根据计算结果分析了在不同纬度和季节各种地形下辐射收支各分量的差异及其随坡地倾角或谷地周围地形遮蔽角的变化规律。 相似文献
954.
Progressive sequence of reactions of the Ryoke metamorphism in the Yanai district, southwest Japan: the formation of cordierite 总被引:2,自引:0,他引:2
T. IKEDA 《Journal of Metamorphic Geology》1998,16(1):39-52
The compositions of biotite and muscovite were examined in terms of the paragenesis and the metamorphic grade in low- to medium-grade pelitic rocks of the Ryoke metamorphism in the Yanai district, southwest Japan. The biotite and muscovite that coexist with K-feldspar have a higher K component in an A'KF diagram than those in rocks lacking K-feldspar. This fact reflects an increase in the K2 O content in muscovite, but in biotite it reflects an increase of not only the K2 O content but also of the octahedral vacancy.
At higher metamorphic grade beyond the cordierite isograd, where cordierite coexists with neither chlorite nor K-feldspar, the biotite shows an increase in illite, K Aliv □xii−1 Si−1, and Tschermak components, Alvi Aliv R+−1 Si−1, where □xii and R+ denote the interlayer vacancy and (Fe+Mg+Mn), respectively. A reaction to define the cordierite isograd is proposed by treating this chemical change as being responsible for the first appearance of cordierite, i.e. K,Al-poor biotite+phengitic muscovite=K,Al-rich biotite+cordierite+quartz+water .By treating this as a key reaction in medium-grade metamorphism, a set of reaction in a progressive metamorphism is established for the Ryoke metamorphism, a typical low-pressure type metamorphism. Some textures in one of the high-grade areas, the K-feldspar-cordierite zone, suggest that a further two prograde reactions have taken place, i.e. andalusite+biotite+quartz=cordierite+K-feldspar+water
and andalusite=sillimanite.quartz=cordierite+K-feldspar+water
This implies that this zone probably has a P–T path involving isobaric heating. 相似文献
At higher metamorphic grade beyond the cordierite isograd, where cordierite coexists with neither chlorite nor K-feldspar, the biotite shows an increase in illite, K Aliv □xii−1 Si−1, and Tschermak components, Alvi Aliv R+−1 Si−1, where □xii and R+ denote the interlayer vacancy and (Fe+Mg+Mn), respectively. A reaction to define the cordierite isograd is proposed by treating this chemical change as being responsible for the first appearance of cordierite, i.e. K,Al-poor biotite+phengitic muscovite=K,Al-rich biotite+cordierite+quartz+water .By treating this as a key reaction in medium-grade metamorphism, a set of reaction in a progressive metamorphism is established for the Ryoke metamorphism, a typical low-pressure type metamorphism. Some textures in one of the high-grade areas, the K-feldspar-cordierite zone, suggest that a further two prograde reactions have taken place, i.e. andalusite+biotite+quartz=cordierite+K-feldspar+water
and andalusite=sillimanite.quartz=cordierite+K-feldspar+water
This implies that this zone probably has a P–T path involving isobaric heating. 相似文献
955.
稳健协同克立格因子分析及其在化探中的应用 总被引:5,自引:0,他引:5
稳健协同克立格因子分析集稳健统计、协同克立格和因子分析的优点于一体,可同时研究多个变量不同方向的结构差异及变化性,用该方法研究次生晕指示的结构特征可在一定程度反映原生晕的特征,揭示其深层次信息.对团结沟金矿区次生晕分析表明:在矿产预测中矿床原生晕组合标志并不适用于次生晕及分散流的研究,本方法对大(中)比例尺次生晕、分散流与原生晕的信息转换和关联有独到之处. 相似文献
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958.
基于湖南省92个站点1968—2017年冰雹观测资料,采用回归分析、小波分析、主成分分析等方法,研究了湖南冰雹时空分布特征。结果表明,湖南近50年冰雹天气年际下降趋势显著,近20年来有记录的冰雹天气发生频次明显降低。湖南初次降雹的时间都集中在1—3月。冰雹月季变化显著,一年中以3月冰雹最多,2月的次之,从5月份起雹日骤然减少。春季是降雹最多的季节,占雹灾总数的56.06%,冬季的次之,夏季和秋季冰雹发生频率分别仅为全年的2.53%和0.69%。年冰雹日数主要存在4~5 a和19 a左右的振荡周期,20世纪90年代前还存在明显的9~10 a的振荡周期。各季节冰雹日数振荡周期不一。湖南冰雹空间分布呈自湘西北向湘东南递减的规律,年冰雹日数的空间分布特征与春季、冬季冰雹分布特征相似。湘北和湘中地区冰雹天气年际变化以下降趋势为主,湘南地区其气候趋势变化不明显。对湖南近50年冰雹日数进行主成分分析的前3个主要模态,在空间向量场上分别呈现出全省一致型、地势主导型和南北呼应型。 相似文献
959.
SUIZhenghong KlausV.Kowallik 《中国海洋大学学报(英文版)》2004,3(2):141-144
1 Introduction Photosyntheticdinoflagellatesareimportantprima ryproducersandcausesoftoxic‘redtide’ .Theyarefoundinmostaquaticenvironmentsandformamajorpartofthemodernplankton .Dinoflagellatesmaybeimportantindicatorsofenvironmentalstatus (Dale ,1996 ) .… 相似文献
960.
海温与鲁西南夏季降水分析及在长期预报中的应用 总被引:2,自引:0,他引:2
本文对北太平洋海温与鲁西南夏季降水关系进行相关分析建立12个相关场,得出赤道海域,黑潮海域和北太平洋海域三大主要优势相关区。选出35个预报因子进行主成份分析,应用前10个合成主成份变量建立预报方程,收到了较好的预报效果。 相似文献