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81.
For the Argo Project, monitoring the global upper ocean by a large number of profiling floats, maintaining the quality of salinity data is critical; the goal for measurement accuracy is ±0.01. Experiments using the method of Wong et al. (2003), the standard delayed-mode quality control (dQC) for the Project, show that its performance depends critically on the reference datasets used. This study concludes that the method is useful for Argo and has sufficient potential to achieve the goal for salinity measurement in the North Pacific, when suitable reference datasets are prepared. Considering the Wong et al. (2003) algorithms, we suggest that reference datasets with the following characteristics will be most suitable for Argo dQC: They should be basically derived from the most extensive datasets, such as the latest World Ocean Database; in regions with denser observations, datasets with carefully quality controls should be used; in the regions with subsurface temperature inversions, such as the subarctic North Pacific, the profiles used for the reference must extend below the deepest temperature maximum to prepare proper salinities for the deep layer reference.  相似文献   
82.
The aim of this paper is to study whether the features of perennial summer over the South China Sea remain constant all the year round or not , and whether there are any seasonal differences throughout the year or not. According to the characteristics of remarkable monsoon and frequent typhoon, the influences of monsoon and tropical cyclone on the hydrological features and the seasonal structure over the South China Sea are analysed by using examples. It may be considered that in the perennial summer area over the South China Sea, it is summer all the year round, but it does not remain constant throughout the year. On the basis of index dates of developing stages for winter and summer monsoons as well as the seasonal characteristics of typhoon frequency,the perennial summer season over the South China Sea may be divided into four periods, namely, early summer, midsummer, sweltering summer and late summer. The concrete classification and the hydrological seasonal feature of each period are discussed.  相似文献   
83.
In weather sciences, the two specific terms “storm” and “cyclone” frequently appear in literature and usually refer to the violent nature of a number of weather systems characterized by central low pressure, strong winds, large precipitation amounts in the form of rain, freezing rain, or snow, as well as thunder and lightning. But what is the connection between these two specific terms? In this paper, the historic evolutions of the terms “storm” and “cyclone” are reviewed from the perspective of...  相似文献   
84.
根据光(温)敏雄性核不育系水稻的育性模型导出的育性转换临界温度和临界日长指标,用15个代表站1951-1988年逐日平均气温和理论日长分析了7001sN5088s和安农s-1三不育系的育性转换日期及不育期和发育期长度的气候学特征,为二系法杂交水稻的育性转换提供一种实用分析方法,并为生产提供依据。  相似文献   
85.
中国大气逆辐射的气候计算及其分布特征   总被引:5,自引:0,他引:5  
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86.
近50年安徽省太阳总辐射的时空变化特征   总被引:3,自引:0,他引:3  
卢燕宇  田红  鲁俊  温华洋 《气象科技》2016,44(5):769-775
采用1961—2010年安徽省辐射观测数据和常规气象要素观测资料,建立了太阳总辐射的气候学计算方法;进而推算了安徽省各地太阳总辐射,并采用趋势分析、突变检验和小波分析等方法研究了其时空变化特征。结果表明:以理论天文辐射为起始值所建立的全省统一公式,能够较好的拟合安徽省月尺度的太阳总辐射值。根据公式推算的安徽省各地太阳总辐射资源的丰富程度以3级为主,空间分布呈北多南少的特征,季节分布为夏多冬少单峰型,但在梅雨期存在波谷。近50年来安徽省各地太阳总辐射量基本呈一致的减少趋势,全省平均下降趋势为每10年减少0.31 MJ·m-2·d-1,近年来辐射下降趋缓。安徽省太阳总辐射在20世纪80年代初存在一次突变现象;近50年总辐射量以准10年和4~6年左右周期振荡较为明显,而20世纪80年代以来年代际振荡信号减弱,并且太阳总辐射气候态以偏少为主。  相似文献   
87.
近40年潍坊地区雷暴日的气候特征   总被引:18,自引:4,他引:18  
山义昌  王善芳 《气象科技》2004,32(3):191-194
利用潍坊地区不同地理位置的 4测站观测资料 ,分析了 1 96 0~ 1 999年 (4 0年 )潍坊地区初、终雷暴日各地域的差异和变化趋势。结果表明 :初雷暴日 4 0年提前了 8天 ,终雷暴日变化趋势呈抛物线型 ;雷暴期各地域不同 ,基本规律是 :寿光 >青州 >诸城 >潍坊 ;雷暴日的年均频数寿光 2 8 0天 ,青州 2 7 5天 ,诸城 2 6 5天 ,潍坊 2 6 3天 ,平均倾向率每 1 0年 - 1 2天 ;雷暴频数的月分布呈单峰形 ,前半夏沿海大于山区 ,后半夏山区大于沿海 ;候平均气温上升 (下降 )稳定通过 8℃ ,是初雷暴日 (终雷暴日 )的温度阈值  相似文献   
88.
A special feature of the Bay of Bengal circulation is its seasonal variation in response to the monsoonal winds. In the case of the Bay of Bengal, observationally very little is known about the large scale circulation. Theoretically, the problem of driving the circulation in the Bay of Bengal is more complex than that in other basins because of the presence of large quantities of fresh water discharge from Ganga-Brahmaputra-Meghna river systems, and also because the atmospheric driving forces even within a season are highly variable with frequent occurrences of tropical disturbances. Exploring the nature of the circulation in the Bay of Bengal is a problem of great importance in itself as well as for the critical role this region plays in the genesis of tropical disturbances which are the main source of large scale rainfall over the northern part of the Indian subcontinent. The surface circulation of the Bay of Bengal may, therefore, help in understanding the variation of rainfall over time scales ranging from the subseasonal to the interannual. Keeping this in view, an attempt was made towards the development of an oceanic climatological circulation model for the Bay of Bengal, which explains the seasonal variability of the currents. The model is fully non-linear and vertically integrated, with realistic basin geometry. The treatment of coastal boundaries involves a procedure leading to a realistic curvilinear representation of the western and eastern sides of the Bay of Bengal. This coastal representation has the advantage of taking into account the finer resolution in the shallow regions of the northern Bay. The model is forced by the monthly mean wind stress derived from 30 years (1950–79) of Comprehensive Oceanographic Atmospheric Data Sets (COADS). Special emphasis is given to the southern open boundary condition for the model. For this purpose, sensitivity experiments have been performed with six open boundary conditions and a comparative study of the results has been made. These sensitivity tests for the open boundary condition will help the development of a suitable coupled ocean-atmosphere model for this region. The model-generated main features are in general agreement with the known climatological circulation of the Bay of Bengal.  相似文献   
89.
中国地表潜热的气候计算及其分布   总被引:2,自引:0,他引:2  
从整理全国仅有的6个热平衡站实测梯度资料着手,初步讨论了我国地表潜热的气候计算方法,提出新的潜热气候计算式 LE=14.73exp(0.5H+0.069e)(1+0.013△T)u^-0.16 据此计算出全国各站的月,年平均潜热通量密度并分析了其在全国的地理分布和年变化特点,得出一些有意义的结果。  相似文献   
90.
对江浙登陆台风的研究   总被引:2,自引:0,他引:2  
李曾中  贾秀娥  邵俊年 《气象》1993,19(6):8-11
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