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31.
基于三维全动力POM海洋模式,根据2008年6月1日海监飞机监测绿潮所在位置,采用拉格朗日粒子追踪法反向积分,追溯绿潮来源。数值模拟结果显示,回溯至5月中旬,绿潮主要来源于黄海南部江苏连云港和盐城近海海域。黄海绿潮溯源数值模拟,为政府相关部门了解绿潮的源头,并采取相应的措施提供依据,进而为保护生态环境、防灾减灾做贡献。  相似文献   
32.
The major problems encountered in studying estuarine particulate organic matter (POM) are the characterization and quantitation of different kinds of materials (e.g. detrital and living matter, algal and bacterial matter…) each type contributing a specific role in the ecosystem. The study of the activity of the electron transport system (ETS) is proposed as a tool for resolving these problems. Results obtained in our laboratory with cultures of planktonic algae and bacteria provided us with numerical relationships between ETS activity and various organic components such as chlorophyll, carbon and protein. These relationships were: ETS activity/chlorophyll = 2.6, carbon/ETS activity = 17.3, protein/ETS activity = 9.6 in algae; carbon/ETS activity = 5.9, protein/ETS activity = 7.7 in bacteria (ETS activity expressed in /i2h−1 at 20°C; chlorophyll, carbon and protein in μg). Such data can be applied in field studies to characterize the living algal and bacterial matter and, by difference, the detrital organic matter. We report here a study of the Loire estuary as an example.  相似文献   
33.
Peatlands cover a very small area of the Earth, but store globally significant quantities of carbon and export disproportionate quantities of fluvial organic carbon, especially when the peatlands are degraded or disturbed. Peatland headwater catchments with high concentrations of dissolved and particulate organic carbon (DOC and POC) provide an opportunity to investigate the possibility of competing effects that could lead to enhanced or diminished turnover of DOC in the presence of POC. Both POC and DOC can be degraded by light and microbes, producing smaller molecules and releasing CO2 and CH4 to the atmosphere, and POC can inhibit light penetration, stabilize DOC by providing adsorption sites and providing surfaces for microbes to interact with DOC. However, the majority of peatland fluvial carbon studies are conducted using filtered water samples, and measure only the DOC concentration, so the impact of the particulate organic matter (POM) on in-stream processing of organic carbon is relatively unknown. It is therefore possible that studies have underestimated carbon transformations in rivers as they have not considered the interaction of the particulate material on the dissolved concentrations; there could be higher losses than previously estimated, increasing the contribution of peatland headwaters to GHG emissions. In this study, we assessed if the current approach of DOC degradation studies accurately represent the impact of POM on DOC degradation, by quantifying DOC production from POM, and therefore POC, over time in water with manipulated POM concentrations. Both filtered and unfiltered water lost 60% of the DOC over 70 hours, whereas the treatment with additional POM lost only 35%. The results showed that filtering does not significantly impact the DOC degradation rates; however, when the POC concentration was doubled, there was a significant reduction in DOC degradation, suggesting that filtering would still be necessary to get accurate rates of DOC transformations in waters with high POC concentrations.  相似文献   
34.
POM模式在厦门湾三维水动力环境模拟中的应用   总被引:1,自引:1,他引:0  
本文基于采用干湿网格动边界技术的POM模式,模拟了厦门湾全海域潮流场和温盐场的三维结构特征.结果表明,该模式可较好地模拟具有大量浅滩和复杂地形的厦门湾海域的三维水文动力环境.  相似文献   
35.
Satellite remote sensing observations show that during winter, sea surface temperature (SST) presents the structure of double warm tongues in the Huanghai Sea trough:the western and the eastern warm tongues. Numerical experiments based on POM are carried out to study the forming mechanism of this thermal structure and its relation to the Huanghai Sea Warm Current (HSWC). The control experiment reproduces this phenomenon quite well, and comparing experiments investigate the effect of wind and tide. It is found that the western warm tongue is mainly caused by the HSWC, which can be strengthened by wintertime southward wind. The eastern warm tongue develops under the influence of an anti-clockwise circulation which is induced by the temperature front of the Huanghai Sea Cold Water Mass (HSCWM) in summer and autumn. In the eastern portion of this circulation, the northward current carries warm water to the north, forming the eastern warm tongue, which remains till winter.  相似文献   
36.
常用海洋数值模式简介   总被引:4,自引:0,他引:4  
OGCM(Ocean General Circulation Model普通海洋环流模式)简单的说就是把海洋原始方程组离散求解的过程.鉴于实际观测资料较少,无法满足研究需求,用数值模式进行数值模拟是实用的研究方法之一,目前海洋学界较为常用的OGCM有POM、FVCOM、HAMSOM、HYCOM等.这些模式有些适用于近岸海域,有些适用于大洋,各有其自身的特点.本文作者在对以上各模式使用与理解的基础上,对这几种模式进行了介绍,并对如何选用一个合适的模式给出了建议.  相似文献   
37.
半封闭高密度筏式养殖海域水动力场的数值模拟   总被引:9,自引:0,他引:9  
基于2006年4月和7月在中国北方典型筏式养殖海域--桑沟湾的潮流特征的观测,对养殖设施(筏架与浮子等)和养殖生物(海带等)带来的阻力分别进行参数化,修改POM模型,对桑沟湾水动力场进行模拟,进而以此水动力模型驱动水质模型模拟该湾半交换时间,并与不考虑养殖阻力的模拟结果进行比较.结果表明:(1) 加入养殖阻力的水动力模型能模拟出更加真实的潮流流速大小和垂直结构特征,即筏式养殖活动带来的潮流上边界层的存在.(2) 由于养殖活动的影响,桑沟湾的流速减小40%,平均半交换时间延长71%.因此,如果忽视养殖活动本身对海水流动的阻碍作用,会高估桑沟湾的流速大小,高估营养盐和颗粒物的更新补充速度,进而影响对该养殖海域的养殖容纳量的评估.  相似文献   
38.
渤海冰-海洋耦合模式——I.模式和参数研究   总被引:1,自引:0,他引:1  
在国内外冰-海洋耦合模式研究基础上,根据渤海水文、气象和冰情特点,以国家海洋环境预报中心的渤海海冰预报模式和POM海洋模式为基础,开发了一个冰-海洋耦合模式.在该耦合模式中,冰和海洋之间的动量和热量交换是双向的,冰厚和冰密集度的变化不仅由冰表面和冰底的热收支决定,还由开阔水的表面热收支决定.侧重阐述了耦合模式的动力和热力学过程的耦合,并对模式中一些热力参数进行了讨论.  相似文献   
39.
An Eta-Coordinate Version of the Princeton Ocean Model   总被引:1,自引:0,他引:1  
The Princeton Ocean Model (POM) is widely used in both the research and real-time marine forecast communities. However, there is a single heavily criticized feature and shortcoming of POM, i.e., the pressure gradient (PG) error associated with sloping topography. To overcome this problem, in this paper we present an eta-coordinate POM (ECPOM). The eta-coordinate system was originally adopted in atmospheric numerical models and has proved to be effective in removing the large errors associated with the horizontal pressure gradient force and advection and diffusion terms along a steeply sloping topography. A familiar idealized seamount problem is used to test the PG error in the ECPOM in order to isolate errors from other sources, as is done in the literature. The model is set up so that, ideally, the ocean should be at rest forever; any development of circulation is regarded as numerically artificial. Results show that in ECPOM, errors are dramatically reduced by two orders of magnitude over a wide range of parameters. As a trade-off, the bottom boundary of the ECPOM is a stepwise instead of a continuous one, as in the sigma-coordinate POM (SCPOM). Modification of the SCPOM to the ECPOM is straightforward and minimal. Compared to the z-coordinate model, the ECPOM is numerically simpler since the eta-coordinate has a surface-following character. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
40.
According to the earlier international studies on the coupled ice-ocean model and the hydrology, meteorology, and ice features in the Bohai Sea, a coupled ice-ocean model is developed based on the National Marine Environment Forecast Center's (NMEFC) numerical forecasting ice model of the Bohai Sea and the Princeton ocean model (POM).In the coupled model, the transfer of momentum and heat between ocean and ice is two-way, and the change of ice thickness and concentration depends on heat budget not only at the surface and bottom of ice, but also at the surface of open water between ices. The dynamic and thermodynamic coupling process is expatiated emphatically. Some thermodynamic parameters are discussed as well.  相似文献   
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