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1.
东海黑潮热输送变异与经向风异常   总被引:7,自引:0,他引:7  
根据日本气象厅1956-2003年在PN断面获得的观测资料和NCEP 850 hPa风资料,分析了东海黑潮热输送的变异特征,并探讨了冬、夏季热输送与风异常的关系.结果表明,黑潮通过PN断面多年平均的热输送达16.52×1014 W,热输送的年际和年代际变化都很明显,其主要变化周期为准2 a,5 a和22 a.黑潮热输送在1976年前后发生了一次由弱到强的气候跃变.黑潮热输送具有很强的长期的线性增加趋势,在1956-2003年增加了约6.51×1014 W.相关与合成分析结果显示,南海南部和黑潮流域上空的经向风异常对东海黑潮热输送的年际变化有重要影响,即当偏南风异常增强时,黑潮热输送将加强,反之将减弱.  相似文献   

2.
1972—1983年期间东海(PN断面)的黑潮流况   总被引:3,自引:0,他引:3  
本文利用1972—1983年期间PN断面的温盐和GEK资料,分析和讨论了东海黑潮的流况。计算证实:1.PN断面0—800米层黑潮的12年平均体积输送量约为20×106米3/秒;2.平均体积输送量有春夏强而冬秋弱的季节性变化,但幅度不大;3.PN断面的体积输送量出现高值时期恰对应了日本南部黑潮的大弯曲。并且发现,此大弯曲往往出现于PN断面上的黑潮体积输送量发生季节性陡增之后。最后,文章还讨论了PN断面、E断面和苏澳—与那国岛断面处黑潮各段体积输送量变化的差异。  相似文献   

3.
本文基于日本气象厅1956—2005年间在东海PN断面获得的观测资料,结合NCEP风场资料,研究了东海黑潮流量的年际和年代际变化特征,并探讨了西北太平洋风场和太平洋年代际振荡(PDO)对黑潮流量年际和年代际变化的影响。结果表明,东海黑潮流量基本服从正态分布,主要集中在19—33Sv范围内,其多年平均值为24.30Sv(1Sv=106m3/s);季平均、冬、夏季黑潮流量都存在着显著的年际和年代际变化。东海黑潮流量输送具有长期的线性增强趋势,在1956—2005年间它们分别增加了8.73Sv、9.86Sv和9.38Sv。相关与合成分析结果表明,黑潮源区和东海黑潮流域上空的经向风异常是黑潮流量年际变化的重要影响因素,而PDO则对黑潮流量的年代际变化有重要作用。  相似文献   

4.
许达  马超  鞠霞 《海洋科学进展》2020,38(3):400-411
根据日本海洋数据中心提供的1972—2017年PN断面共181个航次和1987—2010年TK断面共92个航次的CTD调查资料,利用动力高度法估算了这2个断面的流量,分析了其季节、年际和长期变化特征。主要结果表明,PN断面流量季节变化为冬、春和夏季大而秋季小,TK断面流量季节变化为冬、夏季大而春、秋季小,二者共同点为最大(小)流量均出现在夏(秋)季。PN断面年平均流量的年际变化不明显,但冬季和夏季流量分别具有准3 a和准2 a的显著变化周期;TK断面年平均流量具有准4 a和准6 a的显著变化周期,冬季流量具有准4 a和准7 a的显著变化周期,但夏季流量无显著变化周期。此外,PN断面流量在1976年附近出现了一次较大幅度的增加。PN断面流量具有较大的长期增加趋势,增长率约为0.3 Sv/a,在1972—2017年增加了约13 Sv,结合NCEP海面风应力资料,结果显示,北太平洋更高纬度带(35°N和40°N)的风应力旋度对PN断面流量的影响更强。  相似文献   

5.
基于长时间序列的水温和盐度资料,通过动力计算方法估算了源区黑潮(18°N断面)热输送量,分析了源区黑潮热输送变异和中国近海SST异常的年际、年代际时空变化特征及两者之间的相互关系.结果显示,源区黑潮热输送异常呈现出显著的以2—7、10~20a和约30a为主周期的年际、年代际变化,且具有线性增强的长期变化趋势.并约于1976年前后发生了一次显著气候跃变.中国近海SST年际、年代际异常变化的最显著区域位于渤海、黄海、东海海域和台湾海峡.源区黑潮热输送变异在年际、年代际尺度上与中国近海SST异常变化密切相关,源区黑潮热输送变异可能是影响中国近海SST异常变化的重要因素之一.  相似文献   

6.
基于东海PN断面多年CTD实测资料,主要从PN断面上的温盐结构和声场结构两个方面进行研究,统计分析PN断面上东海黑潮边界锋的水文要素特征。文章利用Matlab软件对资料中所涉及的温盐数据绘制等值线图,描绘出PN断面上关于测站位置、温盐分布特点,利用Mackenzie公式计算声速分布及其变化,从而构成温、盐、声三种要素的断面分布图。此外还进一步分析了PN断面温盐断面结构,得到黑潮锋的分布与强度特征。并对黑潮锋的季节变化规律进行分析,得出夏秋季节黑潮在PN断面上的海洋锋强度相对于冬春季节要大、冬季最弱等结论。  相似文献   

7.
1987—2010年PN、TK断面黑潮流场的时空变化   总被引:1,自引:0,他引:1  
基于1987-2010年PN断面和TK断面长期水文调查资料,使用逆方法计算了黑潮在这两个断面的流场,进而分析了其时空变化.结果表明,黑潮流量变化的主要周期为准4年和1年,季节变化呈夏强秋弱.两个断面流场的EOF分解的主模态表明:在PN断面,流场变化主要是同位相的,说明了黑潮流量的变化对流场起调控作用;而在TK断面,南北两个海沟中流场呈反位相变化,说明黑潮的路径变化是影响流场变化的主要因素.  相似文献   

8.
东海黑潮热输送及其与黄淮平原区汛期降水的关系   总被引:22,自引:0,他引:22  
根据日本气象厅1956—1990年PN(G)断面观测资料分析东海黑潮热输送的变异特征,并探讨其冬季热输送与黄淮平原区汛期(6-8月)降水的关系。结果表明,黑潮通过PN(G)断面多年平均的热输送达15.74×1014W,其中冬季热输送的年际和长期变化特别明显;冬季热输送年际变化的周期主要为对.23.4a、3.5a、和2.6a,长期变化总趋势是70年代末以前各年热输送距平均为负值,对年代末接近多年平均值,进入80年代各年距平值不仅为正且逐年增大;东海黑潮冬季热输送与黄淮平原区汛期降水具有相近的长期变化趋势,两者间存在较好的负相关关系。  相似文献   

9.
台湾以东黑潮经向热输送变异及可能的气候效应   总被引:5,自引:4,他引:1  
基于日本气象厅长序列水文再分析资料,通过估算台湾以东黑潮24°N断面热输送量,分析了该断面黑潮热输送的低频变异特征,并探讨了热输送变异与我国近海海表温度异常变化以及前期(前秋、前冬和春季)和同期(夏季)热输送变异与我国夏季降水异常变化的关联性。小波分析显示,台湾以东黑潮(24°N断面)热输送异常存在着显著的准2 a周期振荡和约16 a的年代际变化,且以上显著周期主要存在于20世纪60年代中期以后,另外,台湾以东黑潮(24°N断面)热输送变异的季节差异明显;50多年来,台湾以东黑潮(24°N断面)热输送呈现出长期增强趋势,但变化幅度不大,且各季节长期趋势也有所不同。相关分析表明,台湾以东黑潮(24°N断面)热输送低频变异可能是我国东部近海SST变化的一个重要因素。另外,回归分析发现,前期及同期台湾以东黑潮(24°N断面)热输送变异对我国东部夏季降水异常变化有显著指示性,可能存在较大影响。  相似文献   

10.
南海北部海面高度季节变化的机制   总被引:2,自引:1,他引:2  
利用POM模式对南海环流进行了数值模拟和数值试验 ,结果表明 :南海北部SSH的变化主要应归于南海局地的动力、热力强迫和黑潮的影响 ;黑潮对南海北部SSH平均态的影响要大于对SSH异常场的影响 ;对于南海北部深水区冬季局地风应力与浮力通量的作用相反量级相同 ,黑潮对南海北部SSH的控制作用在冬季显得最重要 ,约占 50 %~ 80 % ;春季 ,夏季和秋季 ,局地风应力、浮力通量和黑潮三者都使深水区SSH上升 ,局地风应力使深水海盆SSH上升的作用约占 4 0 %~ 6 0 % ,浮力通量的作用约占 2 0 % ,黑潮的影响约占 2 0 %~ 30 % .在夏季 ,尽管南海北部深水海盆SSH达到全年最高 ,但黑潮对南海北部深水海盆SSH的贡献最小 .在广东沿岸陆架海域 ,SSH季节变化的机制与深水海盆SSH季节变化的机制不同 :春、夏季 ,局地风应力使SSH上升的作用几乎与浮力通量使SSH下降的作用相当 ;秋、冬季 ,东北季风使SSH上升的作用大于浮力通量和黑潮使SSH下降的作用 ,陆架区SSH为正 ,且在海南岛附近达到最大值  相似文献   

11.
《Marine Chemistry》2002,79(1):27-36
Preformed Cd and PO4 were investigated in the northwestern Pacific (Station CM05) and the Okhotsk Sea (Station CM06), and the relationship between the two elements was examined. At CM05, from the apparent oxygen utilization (AOU)–Cd and PO4 plot, the different molecular ratios of consumed O2 to regenerated Cd and PO4 were calculated to be 254,000 (Cd) and 96 (PO4) for the shallow layer (30–99 m) and 613,000 (Cd) and 170 (PO4) for the deep layer (below the oxygen minimum layer), which suggested the preferential remineralization of Cd and PO4 in the shallow layer. At CM06, regeneration ratios of O2/Cd, PO4 were obtained only in the shallow layer (29–124 m) as 227,000 (Cd) and 75 (PO4). The calculated preformed Cd and PO4 concentrations in the shallow layer were 0.59 nM of Cd and 1.6 μM of PO4 at CM05 and 0.35 nM of Cd and 0.95 μM of PO4 at CM06. These concentrations were much higher than those (close to 0) in the low-latitude area, which was attributable to the supply of these constituents from deep water by the strong winter convection. In the deep layer, at CM05, preformed concentrations were 0.64 nM of Cd and 1.4 μM of PO4. Preformed PO4 generally agreed with previously reported values in the Pacific, which suggested that the concentrations of the initial PO4 in the deep water were preserved as preformed through the movement to the northwestern Pacific. On the other hand, obtained preformed Cd in the northwestern Pacific deep water showed a somewhat higher value than that in the southwest Pacific. The possibility of the terrestrial input and remineralization of Cd by CaCO3 dissolution during the northward movement was considered. A plot of Cd and PO4 showed a linear relationship with slopes of 0.34 and 0.40 (nM/μM) at CM05 and CM06, respectively, which generally agreed with the reported values in the North Pacific.  相似文献   

12.
渤海、黄海、东海冬季海流场温度场数值模拟和同化技术   总被引:6,自引:0,他引:6  
利用NASA高分辨率的卫星遥感资料SST,采用Nudging同化来模拟渤海、黄海、东海的三维温度场,减小用热通量作上边界条件所带来的误差.结果表明,模拟的海流场能较好地反映渤海、黄海、东海的环流特征.数据同化后的温度场优于未经同化的温度场.3个选择站点的同化值与实测值的均方根误差分别为1.307,0.526,0.744,用热通量资料模拟的水温与实测值的均方根误差分别为2.160,0.979,1.330.尽管只同化了海表温度,但数据同化对三维温度场结构都有影响.  相似文献   

13.
海南省海岸带和海洋资源与环境问题及对策研究   总被引:7,自引:0,他引:7  
陈春福 《海洋通报》2002,21(2):62-68
在分析海南省海岸带和海洋资源与环境优势的基础上,指出当前存在的5个主要问题,即海洋资源的综合开发利用缺乏统一的规划、海洋防护林和生物资源破坏严重、水质富营养化、海域污染等,并对存在问题提出今后的对策。  相似文献   

14.
体现执法威力 维护海上权益   总被引:1,自引:0,他引:1       下载免费PDF全文
2004年,是我国海洋工作面临历史性机遇和挑战的一年。中国海监总队在国家海洋局的领导和关怀下,在局各有关部门和各分局、各沿海省(自治区、直辖市)海洋厅(局)的大力支持下,坚持以邓小平理论和“三个代表”重要思想为指导,认真贯彻党的十六大和十六届三中、四中全会精神,全面落实局党组2004年的重点工作,以执法能力建设为重点,以海盾系列专项执法、执法示范工作为主线,上下团结一致,与时俱进,开拓进取,认真履行职能,全力推进全国海监队伍建设和海洋执法监察工作。  相似文献   

15.
采用东海黑潮主流段长时间序列的实测温盐资料,研究了东海黑潮上层温度、上层盐度的变化及其与中国东部降水和地面气温的关系.结果表明,在过去50 a内,东海黑潮上层海温呈上升趋势,而上层盐度略呈下降趋势.东海黑潮上层海温和我国东部地面气温的关系在冬季十分密切,呈现出大面积显著的正相关,这与冬季南下冷空气的整体降温作用有关.夏季,长江中下游江水的增多致使大量长江冲淡水入海,可能是导致黑潮上层水盐度下降的一个原因,此时东海黑潮上层盐度与我国大陆东部降水呈负相关.  相似文献   

16.
This is a historical review of Canadian policy at the Third UN Conference on the Law of the Sea. Canadian objectives with regard to the territorial sea, fisheries, pollution prevention and the continental shelf are outlined and the role played by the Canadian delegation at UNCLOS is described. The article then examines the impact of the Convention on Canada, particular attention being paid to the Canadian Exclusive Economic Zone and the Canadian role in the controversy over seabed mining. The author concludes by arguing that Canada was a major beneficiary of the Convention, but that US opposition has placed the future of the Convention in jeopardy.  相似文献   

17.
Micronuclei (MN), nuclear buds (NB) and fragmented-apoptotic cells (FA) were analyzed in mature peripheral blood and immature cephalic kidney erythrocytes of flounder (Platichthys flesus), dab (Limanda limanda) and cod (Gadus morhua) from 12 offshore sites in the Baltic Sea (479 specimens) and 11 sites in the North Sea (291 specimens), which were collected during three research vessel cruises in December 2002, 2003 and in September 2004. The highest levels of environmental genotoxicity (frequencies of MN up to 0.5‰, NB – up to 0.75‰) and cytotoxicity (FA – up to 0.53‰) were observed in flatfishes from areas close to oil and gas platforms in the North Sea and in zones related to the extensive shipping and potentially influenced by contamination from large European Rivers (Elbe, Vistula, Oder). In dab from the offshore zones of the North Sea, the levels of nuclear abnormalities were higher as compared to those in dab from the Baltic Sea. Responses in immature kidney erythrocytes were higher than in mature erythrocytes from peripheral blood. MN frequency lower than 0.05‰ (the Baltic Sea) and lower than 0.1‰ (the North Sea) could be suspected as a reference level in the peripheral blood erythrocytes of flatfish.  相似文献   

18.
The purpose of our work was to obtain the most possible detailed information about the composition, concentration, and structural features of the magnetic minerals contained in the rock to reveal the differences in the magnetic properties of the peridotites under various circumstances of the mantle magmatism and different conditions of metamorphism. To do this, we examined and analyzed the magnetic and petrographic characteristics of four collections of oceanic and alpinotype spinel peridotites. The main object for comparing the magnetic characteristics was the Gorringe ridge, which lies in the eastern part of the Atlantic Ocean. The peridotite samples from the Gorringe ridge differ from the other collections in many magnetic parameters: I n , χ, Q, I rs /I s , H c , H cr , and H m . The principal question of our work was to clarify the nature of the Earth’s crust where the Gorringe ridge formed. This subject was studied many times in the literature, but the researchers did not reach a common opinion. In accordance with our data, the spinel peridotites from the Gorringe ridge represent a subcontinental lithosphere mantle of the Iberian continental margin. During the metamorphism, the formation of magnetite occurred in the peridotites of the Gorringe ridge in several stages and had a regressive character. Our investigations explain the results of the analysis of the anomalous magnetic field over the Gorringe ridge, which is characterized by sharp roughness and high intensity of the local signchanging anomalies.  相似文献   

19.
A conclusion about two extreme regimes existing in the large-scale circulation in the North Atlantic has been drawn based on an analysis of the inter-annual variability of the analogue to the Rossby index, as well as that of the heat and dynamic characteristics in separate areas of the north subtropical circulation. The former is defined by a high level of circulation both in the atmosphere and in the subtropical water circulation. In the current century this regime was realized mainly in the years pertaining to the middle and end of a 22-year solar activity cycle (a 22-year cycle). The relatively low level of atmospheric circulation and the slackened water mass transport are typical of the second regime. It dominated mainly during the years relevant to the beginning and second half of a 22-year solar activity cycle.Translated by Mikhail M. Trufanov.  相似文献   

20.
The upper Oyashio intermediate water, one of the source waters for the Sea of Okhotsk intermediate water, is exhibiting a warming trend. The historical data show that the upper Oyashio temperature increased by 2.4°C during 1953 to 2007 at the potential density of 26.75 at depths of approximately 170 m. This rate of warming is much faster than that of the global ocean and the Sea of Okhotsk. The upper Oyashio warming is likely linked to the penetration of warm water of the Alaskan Stream westward. One mechanism of this warm Alaskan Stream water penetration is associated with large Aleutian eddies.  相似文献   

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