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41.
The vertical distribution of density, salinity, temperature, dissolved oxygen, apparent oxygen utilization, nutrients, preformed phosphate, pH, alkalinity, alkalinity: chlorinity ratio, in situ partial pressure of carbon dioxide, and percent saturation of calcite and aragonite, for the Southeastern Bering Sea, is studied and explained in terms of biological and physical processes. Some hydrological interactions between the Bering Sea and the North Pacific Ocean are explained. The horizontal distribution of dissolved oxygen at 2000 and 2500 m depths, throughout the Bering Sea, indicates that deep water is flowing from the Pacific, through the Kamchatka Strait, and then northward and eastward in the Bering Sea. Based on the dissolved oxygen distribution we estimate roughly that it takes 20 years for the deep waters to move from the Kamchatka Strait to the Southeastern part of the eastern basin. The surface concentration of nutrients is higher in the Bering Sea than in the North Pacific Ocean, probably because of upwelling and intense vertical mixing in the Bering Sea. A multivariable regression analysis of dissolved oxygen as a function of phosphate concentration and potential temperature was applied for the region where the potential temperature-salinity diagram is straight, and the confidence interval of the PO4 coefficient, at the 95% probability level, was found consistent with theRedfield biochemical oxidation model. The calcium carbonate saturation calculations show that the Bering Sea is supersaturated with aragonite in the upper 100 m, and with calcite in the upper 200 m. Below these depths seawater is undersaturated with respect to these two minerals.  相似文献   
42.
Positions of sunspots between 1966 and 1976 as observed at Kandilli Observatory were used to determine the differential rotation of the Sun. A total of 202 sunspot groups which were E, F, G, H, and J-types were chosen, and a least-squares solution was calculated with their daily rotations. A gradient difference was found between the two hemispheres of the Sun.  相似文献   
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44.
地质图形处理系统设计   总被引:5,自引:0,他引:5  
介绍了地质图形计算机处理系统的系统功能、系统结构、图形数据库结构以及图形生成与编辑;讨论了在开发地质图形计算机辅助设计或绘图系统时,应如何体现专业特点,如何在数据中表达地质现象的地层和构造意义,如何在地质模型建立中融入专业人员的地质背景知识,以及怎样设计出实际有效的地质图形处理软件系统等问题。   相似文献   
45.
Geomagnetism and Aeronomy - The comparison of the Quasi Biennial Oscillation (QBO) and F10.7 solar flux effects on Total Mass Density (TMD) obtained from NRLMSIS-00 model for 90 km altitude of...  相似文献   
46.
Geomagnetism and Aeronomy - The kinetic theory is particularly suitable and convenient to calculate the collision parameters in the ionospheric medium. In this study, the mean free path (λ)...  相似文献   
47.
Meng  Zhiyong  Zhang  Fuqing  Luo  Dehai  Tan  Zhemin  Fang  Juan  Sun  Jianhua  Shen  Xueshun  Zhang  Yunji  Wang  Shuguang  Han  Wei  Zhao  Kun  Zhu  Lei  Hu  Yongyun  Xue  Huiwen  Ma  Yaping  Zhang  Lijuan  Nie  Ji  Zhou  Ruilin  Li  Sa  Liu  Hongjun  Zhu  Yuning 《中国科学:地球科学(英文版)》2019,62(12):1946-1991
Synoptic meteorology is a branch of meteorology that uses synoptic weather observations and charts for the diagnosis,study,and forecasting of weather.Weather refers to the specific state of the atmosphere near the Earth's surface during a short period of time.The spatial distribution of meteorological elements in the atmosphere can be represented by a variety of transient weather phenomena,which are caused by weather systems of different spatial and temporal scales.Weather is closely related to people's life,and its development and evolution have always been the focus of atmospheric scientific research and operation.The development of synoptic meteorology is closely related to the development of observation systems,dynamical theories and numerical models.In China,observation networks have been built since the early 1950 s.Up to now,a comprehensive meteorological observation systembased on ground,air and space has been established.In particular,the development of a new generation of dense radar networks,the development of the Fengyun satellite series and the implementation of a series of large field experiments have brought our understanding of weather from large-scale environment to thermal dynamics,cloud microphysical structure and evolution characteristics of meso and micro-scale weather systems.The development of observation has also promoted the development of theory,numerical model and simulation.In the early days,China mainly used foreign numerical models.Lately,China has developed numerical model systems with independent intellectual property rights.Based on the results of high-resolution numerical simulations,in-depth understanding of the initiation and evolution mechanism and predictability of weather at different scales has been obtained.Synoptic meteorology has gradually changed from an initially independent development to a multidisciplinary approach,and the interaction between weather and the change of climate and environment has become a hot and frontier topic in atmospheric science.This paper reviews the important scientific and technological achievements made in China over the past 70 years in the fields of synoptic meteorology based on the literatures in China and abroad,from six aspects respectively including atmospheric dynamics,synoptic-scale weather,typhoon and tropical weather,severe convective weather,numerical weather prediction and data assimilation,weather and climate,atmospheric physics and atmospheric environment.  相似文献   
48.
The main challenge in predicting global responses of floating vessels in deepwater and ultra-deepwater areas comes from the system's coupled effect.In this paper,the coupled approach is used to analyze effects of riser on floating system in deepwater.The analysis results show that the coupling effects of risers will mainly affect the low frequency (LF) motions of the system.That is because risers will provide the system with a significant low frequency (LF) damping which will vary with the sea states.Under ...  相似文献   
49.
Contourlet变换和Tsallis熵的多源遥感图像匹配   总被引:1,自引:0,他引:1  
吴一全  陈飒 《遥感学报》2010,14(5):899-910
提出了一种利用Contourlet变换、Tsallis熵和改进粒子群优化的多源遥感图像匹配算法。在分别对参考图像和目标图像进行Contourlet分解的基础上,以基于Tsallis熵的互信息量作为相似性度量准则,利用改进的带极值扰动的简化粒子群优化算法对低分辨率的遥感图像进行匹配操作,逐级上推,最终实现全分辨率情况下多源遥感图像的匹配。实验结果表明,与常用的遥感图像匹配算法相比,该算法匹配精度高,稳健性好,且运算量大幅减少。  相似文献   
50.
济青高速公路大雾天气气候特征及其影响   总被引:30,自引:3,他引:30       下载免费PDF全文
张飒  冯建设 《气象》2005,31(2):70-73
利用济青高速公路沿线13个气象站1971~2000年的地面观测资料,分析了济青高速公路沿线大雾天气的天气气候特征,发现:济青高速公路沿线大雾天气不仅具有明显的年际变化,而且具有明显季节、昼夜和地域差异,并在此基础上将不同路段大雾服务划分为特别关键期、关键期、次关键期。结合实际交通气象服务的需要,将大雾天气对于高速公路的影响划分为4个等级,并提出了未来开展高速公路大雾服务的设想。  相似文献   
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