冬季青岛-石岛近海中尺度涡旋数值模拟   总被引：1，自引：0，他引：1  

徐丹亚  赵保仁 《海洋科学》1998,22(2):64-67

利用二维全流水动力方程组,在考虑了海面风应力,潮余流和一开边界入流等条件下,首次模拟出了石了石岛附近的中尺度反旋式涡旋海水运动,并对南黄海西部冬季环流的特征作了初步探讨。数值模拟结果和实测吻合良好,数值模拟表明：冬季南黄海西部环流形式主要决定因子是海面风应力、潮余流及从开边界的流入该海域的黄海暖流及黄海沿岸流。黄海暖流在偏北风作用下沿西北方向可直达山东半岛近岸,后分为两支：一支向南汇入黄海沿岸流流  相似文献   

An assessment of a nowcast/forecast system for the straits of Florida/Florida Current regime     

Christopher N.K. Mooers Inkweon Bang 《中国海洋大学学报(英文版)》2005,4(4):288-292

The Florida Current （FC） largely fills the Straits of Florida and is variable on a broad spectrum of time and space scales. Some portions of the variability are due to variable forcing by tides, winds, heating/cooling, and throughflow; other portions are due to intrinsic instabilities of the FC. To predict, as well as to better understand this complex regime, a nowcast/forecast system （East Florida Shelf Information System （EFSIS）） has been implemented and assessed （http：//efsis. rsmas. miami. edu）. EFSIS is based on an implementation of the Princeton Ocean Model （POM） with mesoscale-admitting resolution on a curvilinear grid. It is forced by a mesoscale numerical weather prediction system （called Eta） run operationally by the National Centers for Environmental Prediction （NCEP）, eight tidal constituents from a global tidal model, and lateral boundary conditions from an operational global ocean prediction model, i.e., the Navy Coastal Ocean Model （NCOM）. Real-time observations of coastal sea level, coastal sea surface temperature, coastal HF radar-derived surface current maps, and FC volume transport are used to verify and validate EFSIS. EFSIS is part of an evolving strategy for real-time predictive coastal ocean modeling methodology, and for fostering the understanding of the variability of the regime on several time and space scales. Here, some of the verification and validation results are provided, as well as diagnostic analyses of dynamical processes. The central point is that an example is provided of a ＇scientific revolution＇ in progress that combines real-time observations and numerical circulation models to yield a credible sequence of synoptic views of coastal ocean circulation for the first time.  相似文献   

Evolution of the North Atlantic Current and Barents Ice Sheet as revealed by grain size populations in the northern Norwegian Sea during the last 60 ka     

Weiguo Wang  Mengwei Zhao  Yanguang Liu  Min Jiang  Chengqiang Wu  Yang Liu 《海洋学报(英文版)》2021,40(10):106-117

The grain size distribution of bulk sediment samples was decomposed in a core to reconstruct paleoceanographic evolution over the past 60 ka in the northern Norwegian Sea. The results show that sediments consisted of 3–4 grain populations derived from the North Atlantic Current (NAC) and Barents Ice Sheet (BIS). The grain size data suggest three palaeoceanographic evolution stages: (1) an environment affected by BIS and NAC and changed with the interstadial/stadial transition in phase with the Greenland ice-core record at 60–31 ka BP, during which discharge of icebergs and the content of the coarsest population containing ice-rafted debris (IRD) in the sediments increased significantly during stadial, while the fine silt population containing volcanic glasses increased with the enhancement of NAC during the interstadial; (2) an extreme environment controlled by BIS at 31–13 ka BP. BIS reached to its maximum at about 31 ka BP and the turbid plumes that formed at the leading edge of BIS contributed to a significant increase in the clayey population in sediments. Icebergs drained into the northern Norwegian Sea with periodical calving of the BIS at 31–19 ka BP. Subsequently, the ablation of the BIS discharged massive floods with clayey sediments and icebergs into the Norwegian Sea at 19–13 ka BP, resulting in a constant increase in clay and IRD in sediments; and (3) a marine environment similar to the present one under the strong influence of NAC following the complete melting of the BIS after 13 ka BP, NAC is the dominant transport agent and no IRD occurred in sediments. The fine silt populations containing volcanic glasses transported by NAC significantly increased.  相似文献   

Existence,morphology and structure of the Yellow Sea Warm Current Branch approaching waters offshore Qingdao,China   总被引：1，自引：0，他引：1  

Xuejun XIONG  Xiaomin HU  Yanliang GUO  Long YU  Liang CHEN  Yuhuan XUE 《中国科学:地球科学(英文版)》2019,(7):1167-1180

In this study, we focused on full-region cruise survey data, near-bottom continuous mooring observations and sea surface wind products from the western South Yellow Sea in winter; after ensuring the data reliability and accuracy, we processed and analyzed the data. Image resolution experiments were carried out to determine the lowest recognition resolutions for all image types, which represent the resolution characteristics of the data. The existence of a warm water tongue originating from the Yellow Sea Warm Current(YSWC) that approached waters offshore Qingdao was confirmed. For the first time, a high salinity water tongue, corresponding to the warm water tongue, was described and found to be more representative of the YSWC branch path. This warm tongue is a sign of the branch originating from the YSWC, which we defined as the Yellow Sea Warm Current Branch approaching waters offshore Qingdao(YSWC-QDB). The pattern of the warm and salty water tongues showed remarkable rear, branching middle, shrinking neck and expanding top regions. These patterns showed a temporal feature of the tongues, and were the result of multi-temporal branches in front of the YSWC main section as well as the YSWC-QDB crossing the southwestward path of the extension of the North Shandong Coastal Current flowing along the southeast coast of the Shandong Peninsula(NSCC-SESE). Analysis using mooring data at a sensitive and representative station also showed the existence of the YSWC-QDB. It is a probabilistic event that manifests as a northwestward flow that decreases gradually from the bottom to the surface in the early cold air transit stage and consistent in the whole water column profile in the later stage. It varies quasi-periodically with weather processes. It also transports some of the YSWC water stored in the entrance area of the Bohai and Yellow seas under winter wind conditions to the western South Yellow Sea as a compensatory current. This current, caused by northerly winds, especially northwest winds and obstruction of the NSCC-SESE, was present, and strong water reduction and compensation caused significant residual sea level oscillations. The compensatory current, if caused by strong northwest wind,began to appear when its direction was opposite to the wind direction. In addition, confirmation of the YSWC-QDB provides an oceanographic basis for the short cooling time and rapid warming in the Qingdao area in winter. This research provides a basis for further studies of the YSWC-QDB at high spatial and temporal resolutions using large sea surface datasets. For monsoon basin dynamics, this study can also be extended to the whole Bohai and Yellow seas and closed or semi-closed basins on the continental margin.  相似文献   

利用拉格朗日方法探究黑潮近岸分支流在2019年春季的起源深度     

燕杰  侯一筠  刘泽  何源首  胡志顺 《海洋与湖沼》2021,52(5):1137-1144

基于ROMS (regional ocean modelling system)模式模拟出2019年春季东海以及临近海域的环流结构和温盐分布。利用拉格朗日方法定量地研究了2019年春季黑潮近岸分支流在台湾以东起源的深度在100—450 m范围内,平均深度约260 m。通过针对台湾海峡流和台湾以东黑潮强度的敏感性实验,进一步得出结论,增大(减小)的台湾以东黑潮流速会减小(增大)黑潮近岸分支流的强度。而增大(减小)的台湾海峡流流速会增大(减小)黑潮近岸分支流的强度。同时,增大(减小)的台湾以东黑潮流会减小(增大)黑潮近岸分支流起源的平均深度。增大(减小)的台湾海峡流流速也会减小(增大)黑潮近岸分支流起源的平均深度。相关结论可为台湾东北黑潮入侵东海变化规律的研究提供参考。  相似文献   

Wave plus current over a ripple-covered bed     

Jrgen Fredse  Ken H. Andersen  B. Mutlu Sumer 《Coastal Engineering》1999,38(4):594

  相似文献   

北极环极边界流研究及其主要科学问题   总被引：8，自引：1，他引：7       下载免费PDF全文

赵进平  史久新 《极地研究》2004,16(3):159-170

北极环极边界流是新近揭示的重要海洋现象 ,是对北冰洋海洋环流长期研究结果综合得到的概念。在本文中 ,详细介绍了北极环极边界流的主要结构和水团特征 ,论述了研究北极环极边界流的意义和前景 ,深入探讨了北极环极边界流面对的科学问题 ,指出了解决这些问题的关键科研工作。文章指出 ,从整体上研究北极环极边界流是非常重要的 ,需要全面考察北冰洋的质量和能量平衡、深层水通风过程以及水体的混合过程。在进一步的研究工作中需要更多的有针对性的现场观测、开展多学科协作研究。数值模拟仍然是北极环极边界流的重要研究手段 ,需要改善数值模式 ,提高数值模拟的质量。  相似文献   

48ka以来日本海Ulleung海盆南部的海洋沉积环境演化   总被引：2，自引：1，他引：1       下载免费PDF全文

刘焱光  石学法  SUKBong-Chool  李朝新  王昆山  李小艳 《海洋学报》2010,32(1):94-106

晚第四纪以来伴随底层水含氧量的剧烈变化,浅色和深色沉积层的交替出现是日本海半远洋沉积物的主要特征。沉积特征分析表明,日本海Ulleung海盆南部KCES1孔的沉积物具有四种不同的沉积构造:均质、纹层、纹层状和混杂构造。深色沉积层一般具有纹层和纹层状构造,并且与我国内陆的千年尺度东亚夏季风强弱变化记录有很好的对应关系,表明纹层沉积物也具有千年尺度的变化规律,从而进一步说明了冰川性海平面变化和东亚夏季风波动应该是Ulleung海盆南部底层水溶解氧含量变化的主要原因。在暖期,在东亚夏季风降水相对增强的影响下,低温、低盐的东海沿岸水对日本海表层水体的贡献要大于对马暖流的贡献,日本海水体间的交换减弱,最终造成缺氧的海底沉积环境。在冷期,夏季风强度的减弱(冬季风增强)加快了日本海西北部深层水的生成,Ulleung海盆南部的底层水含氧量高,相应地沉积了具均质构造的浅色沉积物;在末次盛冰期最低海平面时,日本海成为一个封闭的海盆,降雨量高于蒸发量,水体出现分层,底层水处于停滞缺氧状态。自距今17.5 ka(日历年,下同)以来底层水含氧量较高,对马暖流逐渐成为影响日本海海洋沉积环境的主要因素。Ulleung海盆南部底层水的含氧量在YD期间有一定程度的降低,东海沿岸水的短暂强盛制约了深层水的流通。自距今10.5 ka以来对马暖流强盛,日本海海底处于富氧的沉积环境。  相似文献   

冬季黄海暖流区的空间变化和年际变化特征   总被引：3，自引：0，他引：3  

王辉武  于非  吕连港  刁新源  郭景松 《海洋科学进展》2009,27(2)

利用了多年连续的冬季水文调查数据,以黄海暖水舌作为黄海暖流的示性指标,采用经验函数正交分解及相关分析的方法,探讨了黄海暖流的年际变化特征,结果表明:1)黄海暖流的强弱存在4～7 a的年际变化周期,并与冬季局地季风的经向分量具有较好的相关关系;2)黄海暖流的流轴存在一个3～6 a的变化周期,而且其流轴的摆动明显受冬季季风纬向分量的影响;3)季风增强,黄海暖流增强且流轴西移.  相似文献   

黑潮的涡分辨率数值模拟     

赵健  吴德星  陈学恩  牟林 《海洋通报》2009,28(5)

本文利用涡分辨率的HYCOM模式,以NCEP月平均再分析资料(1979—1993)为驱动场,并采用单向数值嵌套的方式对黑潮流域进行数值模拟,成功模拟了黑潮流域的高分辨率流场特征。模拟结果显示:黑潮路径符合前人对黑潮的认识;在地形和流量的共同作用下,黑潮对吕宋海峡的入侵呈现多平衡态的特征;日本以南的黑潮路径发生多种时间尺度的摆动(从季节内到年际)。黑潮在PN断面上流速跟同期观测十分相符,流轴集中在陆架破折处,季节变化较弱。台湾岛以东黑潮,东海黑潮以及吐噶喇海峡黑潮的流量符合对应时期观测,并且各自呈现出不同的变化特点。  相似文献