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81.
82.
思维是指人脑借助于语言对客观事物的概括和间接反应的过程,以感知为基础,又超越感知的界限,它探索与发现事物的内部本质联系和规律性,是认识过程的高级阶段。目前国内针对地理解题的思维研究相对较少,本文以浙江省历年选考地理试题为例,总结和提炼出六大解题思维,即:逆向思维、收支平衡思维、比较思维、发散思维、空间思维、辩证思维,旨在帮助学生掌握分析和解答地理问题的方法,从而有效提升高中地理学习和复习效果,增强学生学习地理的兴趣。同时在培养学生的地理解题思维过程中,落实地理学科核心素养的培育。 相似文献
83.
基于CMIP5多模式集合资料的中国气温和降水预估及概率分析 总被引:3,自引:1,他引:3
选用国际耦合模式比较计划第五阶段(CMIP5)提供的30个全球大气-海洋耦合模式(AOGCMs)在典型浓度路径(RCPs)情景下气温和降水量的预估结果,采用扰动法,用站点观测资料作为气候背景场替代AOGCM模拟的气候平均,尝试校正气候预估结果的系统性偏差。通过集合方法,用概率的形式给出中国平均气温升高1 ℃,2 ℃和3 ℃以及降水量增加10%,20%和30%概率的空间分布,讨论了中国未来平均气温和降水量可能的变化。结果表明:经过扰动法处理后的气温和降水量预估集合保留了当前气候的局地信息。预估平均气温在中国均有上升,北方地区尤其是青藏高原地区变暖的程度大于南方地区,北方大部分地区平均气温升高的趋势为0.28 ℃/10a。在21世纪初,中国北方地区年平均气温升高1 ℃的可能性超过50%。到了21世纪末期,中国大部分地区平均气温升高2 ℃的可能性超过60%,新疆北部以及青藏高原南部地区气温升高3 ℃的可能性超过50%。预估中国降水量普遍增多,中国北方地区降水量增多的程度要明显大于江淮流域及其以南地区,尤其是西北地区降水量增多非常显著,降水量增多30%的可能性超过70%以上。 相似文献
84.
Relationships between Interannual and Intraseasonal Variations of the Asian-Western Pacific Summer Monsoon Hindcasted by BCC_CSM1.1(m) 总被引:4,自引:0,他引:4
LIU Xiangwen ;WU Tongwen ;YANG Song ;LI Qiaoping ;CHENG Yanjie ;LIANG Xiaoyun ;FANG Yongjie ;JIE Weihua ;NIE Suping 《大气科学进展》2014,31(5):1051-1064
Using hindcasts of the Beijing Climate Center Climate System Model, the relationships between interannual variability (IAV) and intraseasonal variability (ISV) of the Asian-western Pacific summer monsoon are diagnosed. Predictions show reasonable skill with respect to some basic characteristics of the ISV and IAV of the western North Pacific summer monsoon (WNPSM) and the Indian summer monsoon (ISM). However, the links between the seasonally averaged ISV (SAISV) and seasonal mean of ISM are overestimated by the model. This deficiency may be partially attributable to the overestimated frequency of long breaks and underestimated frequency of long active spells of ISV in normal ISM years, although the model is capable of capturing the impact of ISV on the seasonal mean by its shift in the probability of phases. Furthermore, the interannual relationships of seasonal mean, SAISV, and seasonally averaged long-wave variability (SALWV; i.e., the part with periods longer than the intraseasonal scale) of the WNPSM and ISM with SST and low-level circulation are examined. The observed seasonal mean, SAISV, and SALWV show similar correlation patterns with SST and atmospheric circulation, but with different details. However, the model presents these correlation distributions with unrealistically small differences among different scales, and it somewhat overestimates the teleconnection between monsoon and tropical central-eastern Pacific SST for the ISM, but underestimates it for the WNPSM, the latter of which is partially related to the too-rapid decrease in the impact of E1 Nifio-Southern Oscillation with forecast time in the model. 相似文献
85.
86.
K. Yang J. F. Huntington J. W. Boardman P. Mason 《Australian Journal of Earth Sciences》2013,60(6):915-922
Hydrothermal alteration mapping with spaceborne hyperspectral data was simulated in the Comstock mining district, Nevada in order to evaluate the mineral mapping capabilities of the proposed Australian Resource Information and Environment Satellite (ARIES‐1). As a result, a suite of hydrothermal alteration minerals, including kaolinite, dickite, illite, chlorite, alunite and carbonate was identified from the simulated data in the 0.4–2.5 μm wavelength region and their areal abundance variations mapped accordingly. The recognised alteration zoning shows a major change in alteration assemblages across the Comstock and Silver City Faults, and a gradual variation from north to south along the faults. In the bleached Miocene volcanic rocks, dickite, kaolinite, illite and alunite were recognised. Coexistence of dickite of relatively high temperature, high‐crystallinity kaolinite of medium temperature and low‐crystallinity kaolinite of low temperature suggests supergene processes overprinting earlier hypogene alteration. The bleached rocks probably represent hydrothermal alteration in the fluid up‐flow zones in the central and shallower parts of the hydrothermal system. Illite in the bleached zones is characterised by relatively short AI–OH band wavelengths (2190–2200 nm), indicating no or very low Fe and/or Mg contents. Fault‐controlled propylitic alteration is mapped in the central part of the district mainly in the footwall of the Comstock Fault. The associated illite is characterised mainly by medium AI–OH band wavelengths (2200–2208 nm). This propylitic alteration may be contemporaneous with Au–Ag mineralisation. Additional and more extensive propylitic zones, containing illite with long AI–OH band wavelengths (2204–2216 nm), were mapped in the southern part of the district. These zones resulted from either a pre‐mineralisation propylitic alteration, or the peripheral hydrothermal alteration in the fluid down‐flow zones of the Miocene hydrothermal system. 相似文献
87.
山旺盆地的成因及其地质意义 总被引:3,自引:0,他引:3
前人一般认为山旺盆地是一个深度不大的封闭性淡水剥蚀盆地。笔者认为它是一个火山口成因的封闭—半封闭盆地。盆地的发展经历了3个发展阶段:早期为火山喷发作用形成火山口,并造成火山碎屑物堆积:中期堆积了较厚层的沉积物,主要为粘土质岩石,如硅藻质页岩、泥岩,此外,还有少量的砂岩、砾岩;晚期为玄武岩充填,致使整个盆地完全封闭。在盆地发展过程中,早期为封闭环境,中、晚期为半封闭环境。火山碎屑物的再堆积和分解对于生物死亡和埋藏可能具有重要的意义;该区第三纪中心式火山作用非常强烈,通过详细的区域地质调查,有可能找到更多的化石产地和硅藻土矿。 相似文献
88.
Longitudinal Displacement of the Subtropical High in the Western Pacific in Summer and its Influence 总被引:17,自引:0,他引:17
Using the relative vorticity averaged over a certain area, a new index for measuring the longitudinal position of the subtropical high (SH) in the western Pacific is proposed to avoid the increasing trend of heights in the previous indices based on geopotential height. The years of extreme westward and eastward extension of SH using the new index are in good agreement with those defined by height index. There exists a distinct difference in large-scale circulation between the eastward and westward extension of SH under the new definition, which includes not only the circulation in the middle latitudes but also the flow in the lower latitudes. It seems that when the SH extends far to the east (west), the summer monsoon in the South China Sea is stronger (weaker) and established earlier (later). In addition, there exists a good relationship between the longitudinal position of SH and the summer rainfall in China. A remarkable negative correlation area appears in the Changjiang River valley, indicating that when the SH extends westward (eastward), the precipitation in that region increases (decreases). A positive correlation region is found in South China, showing the decrease of rainfall when the SH extends westward. On the other hand, the rainfall is heavier when the SH retreats eastward. However, the anomalous longitudinal position of SH is not significantly related to the precipitation in North China. The calculation of correlation coefficients between the index of longitudinal position of SH and surface temperature in China shows that a large area of positive values, higher than 0.6 in the center, covers the whole of North China, even extending eastward to the Korean Peninsula and Japan Islands when using NCEP/NCAR reanalysis data to do the correlation calculation. This means that when the longitudinal position of the SH withdraws eastward in summer, the temperature over North China is higher. On the other hand, when it moves westward, the temperature there is lower. This could explain the phenomenon of the seriously high temperatures over North China during recent summers, because the longitudinal position of SH in recent summers was located far away from the Asian continent. Another region with large negative correlation coefficients is found in South China. 相似文献
89.
A two-layer primitive equation model is developed in this paper. The capabilities of this model aretested by the use of multiyearly averaged January and July sea surface level pressure fields and windfields which can be diagnosed from the pressure fields. The results show that the ocean surface currentsand undercurrents in the second layer driven by the sea surface wind and the sea surface pressure areclose to the observation. The results are also compared with that of the IAP OGCM and the OSUOGCM. 相似文献
90.
层序地层学是当前地球科学研究颇为关注的领域,被广泛应用于沉积盆地分析和油气勘探.碎屑岩层序地层学理论方法源于海相盆地,是在被动大陆边缘油气勘探实践的基础上凝练而来的,至今已经历了约50年的发展历程.本文梳理了深海碎屑岩层序过去50年发展历程中的重要进展(包括1970—2000年的经典海相碎屑岩层序地层学、2000—20... 相似文献