Seasonal variations of the ocean surface circulation in the vicinity of Palau   总被引：1，自引：0，他引：1  

Scott F. Heron  E. Joseph Metzger  William J. Skirving 《Journal of Oceanography》2006,62(4):413-426

The surface circulation in the western equatorial Pacific Ocean is investigated with the aim of describing intra-annual variations near Palau (134°30′ E, 7°30′ N). In situ data and model output from the Ocean Surface Currents Analysis—Real-time, TRIangle Trans-Ocean buoy Network, Naval Research Laboratory Layered Ocean Model and the Joint Archive for Shipboard ADCP are examined and compared. Known major currents and eddies of the western equatorial Pacific are observed and discussed, and previously undocumented features are identified and named (Palau Eddy, Caroline Eddy, Micronesian Eddy). The circulation at Palau follows a seasonal variation aligned with that of the Asian monsoon (December–April; July–October) and is driven by the major circulation features. From December to April, currents around Palau are generally directed northward with speeds of approximately 20 cm/s, influenced by the North Equatorial Counter-Current and the Mindanao Eddy. The current direction turns slightly clockwise through this boreal winter period, due to the northern migration of the Mindanao Eddy. During April–May, the current west of Palau is reduced to 15 cm/s as the Mindanao Eddy weakens. East of Palau, a cyclonic eddy (Palau Eddy) forms producing southward flow of around 25 cm/s. The flow during the period July to September is disordered with no influence from major circulation features. The current is generally northward west of Palau and southward to the east, each with speeds on the order of 5 cm/s. During October, as the Palau Eddy reforms, the southward current to the east of Palau increases to 15 cm/s. During November, the circulation transitions to the north-directed winter regime.  相似文献   

Assessments of anthropogenic CO₂ distribution in the tropical Atlantic Ocean     

F. Touratier  C. Goyet  C. Coatanoan  C. Andri 《Deep Sea Research Part I: Oceanographic Research Papers》2005,52(12):2275-2284

With a limited number of properties (salinity, temperature, total dissolved inorganic carbon, total alkalinity, and oxygen) from a recent cruise in the tropical Atlantic Ocean, we use the simple and recent approach TrOCA (Tracer combining Oxygen, inorganic Carbon, and total Alkalinity) to estimate the distribution of anthropogenic CO₂ along three latitudinal sections. In order to assess the quality of the anthropogenic CO₂ distribution, results from the method are compared to the CFC-11 measurements. We discuss the large-scale distribution of the main water masses of the tropical Atlantic Ocean in the light of the anthropogenic CO₂ and the CFC-11 distributions. Keeping in mind that the anthropogenic CO₂ emission began 60 years earlier than that of CFC-11, the former provides new insight on the local circulation and efficiency of the tropical waters to store the atmospheric carbon.  相似文献   

多金属结核瞬时生长速率及其意义   总被引：1，自引：0，他引：1  

孙志国  姚德 《海洋湖沼通报》1996,(1):31-37

本文用Ｘ射线荧光光谱分析，沿结核壳层的生长方向逐点扫描测定铁锰含量，计算结核壳层的瞬时生长速率，划分结核壳层的生长阶段，计算各生长阶段的生长速率，并在结构壳层中建立高分辨率的时间标尺，重建多金属结核生长历史。  相似文献   

南极中山站榴闪岩的变质作用   总被引：1，自引：0，他引：1  

王文正 《海洋湖沼通报》1992,(4):6-11

南极中山站榴闪岩,主要由石榴石、角闪石、石英和斜长石组成。它形成于610～640℃、0.5～O.6GPa的中高压角闪岩相变质条件,是基性岩深成变质作用的产物。  相似文献   

微波辐射计遥感海水盐度的水池实验研究   总被引：1，自引：0，他引：1  

陆兆轼  史久新  矫玉田  曹勇 《海洋技术学报》2006,25(3):70-75,89

通过水池实验研究了L波段微波辐射和盐度的关系,并进行了盐度的反演计算。实验中,先向水池内加入天然海水,然后通过向水池中添加自来水的方式调节降低池内水体的盐度,使盐度从31.67逐步降低到27.48。在此期间,利用微波辐射计观测池内水体的L波段H极化和V极化辐射值以及S波段V极化辐射值,利用CTD观测池内水体的温度和盐度。L波段微波辐射值和根据辐射理论计算出的亮温值具有很好的线性关系。利用最大和最小的2个盐度下的微波辐射值和由辐射理论计算的亮温得到定标公式,将观测的辐射值换算为亮温。最后利用半解析的反演算法反演盐度。本次实验的反演最大误差为2.1,均方差为0.3。  相似文献   

北极海洋沉积物中持久性有机污染物分布特征及分子地层学记录的研究   总被引：5，自引：1，他引：5  

卢冰  陈荣华  王自磐  朱纯  WALTERVetter 《海洋学报》2005,27(4):167-173

持久性有机污染物(POPs)普遍存在于各种环境介质中,其中有机氯农药(OCPs)和多氯联苯(PCBs)化学性质稳定,在环境中能持久残留.它们经食物链浓缩并在生物体内累积,大多数具有致癌、致畸、致突变效应,构成对人类和生态系统的潜在危害,成为世界公认的全球性环境公害.  相似文献   

Ocean circulation and exchanges through the northern Bering Sea—1979–2001 model results     

J.L. Clement  W. Maslowski  L.W. Cooper  J.M. Grebmeier  W. Walczowski 《Deep Sea Research Part II: Topical Studies in Oceanography》2005,52(24-26):3509

We have developed and run a model with sufficiently high resolution (9 km and 45 levels) and a large enough spatial domain to allow for realistic representation of flow through the narrow and shallow straits in the northern Bering Sea. This is potentially important for quantification of long-term mean and time-dependent ocean circulation, and water mass and property exchanges between the Pacific and Arctic Oceans. Over a 23 year interval (1979–2001), mean transport through Bering Strait is estimated to be 0.65 Sv. Comparison of our model results with published observations indicates that ocean circulation is not only variable at seasonal to interdecadal scales but it is also responsive to short-term atmospheric forcing. One of such events occurred during the winter of 2000–2001 with reversed oceanic flow in some areas and much reduced sea-ice cover. Analyses of eddy kinetic energy fields identify some high biological productivity regions of the Chirikov Basin coincident with persistent high energy (up to 2700 cm² s⁻² in the surface layer and up to 2600 cm² s⁻² at mid-depth) throughout the annual cycle. Model output in the Bering Strait region is validated against several time series of moored observations of water mass properties. Comparison with shipboard observations of near-bottom salinity from late winter through autumn indicates that the model reasonably represents the major water-mass properties in the region. The modeled vertical water-column structure in the northern Bering Sea allows increased understanding of the mechanisms of water transformation and transport northward through Bering Strait into the Chukchi and Beaufort Seas. We conclude that the long-term model results for the northern Bering Sea provide important insights into the ocean circulation and fluxes and they are a useful frame of reference for limited observations that are short-term and/or cover only a small geographic region.  相似文献   

南印度洋海区大风天气高纬低压系统模型研究     

杨涛  朱持则  翟国庆  陈信雄 《海洋预报》2007,24(4):71-79

本文根据多年的天气图、卫星云图以及1980～1990年的NCEP再分析资料,通过统计分析和合成分析等方法建立了能够在南印度洋特定海区引起12m/s以上大风天气的高纬低压系统概念模型,并对主要的南印度洋西部副高型、南印度洋倒"品"字型作了详细的阐述。该天气概念模型主要发生在南半球的冬、春季。(1)南印度洋西部副高天气过程多由高纬度低压系统发展引起。在这一过程中,副高与高纬低压系统由纬向型向经向型转变,海平面气压槽和850hPa高度槽受到槽后冷平流的驱动不断向东北方向移动,并扫过南印度洋东部。(2)南印度洋倒"品"字天气模型中,低压槽受斜压系统的驱动东移并发展加深,与南印度洋东部的副高中心之间形成大风带。该天气概念模型的建立对南印度洋海区大风的预报可起到一定指导作用。  相似文献   

分形理论在太平洋多金属结核分布研究中的应用   总被引：2，自引：2，他引：2  

韩喜球  李家彪  王英  金翔龙  李树锋 《海洋学报》2001,23(3):142-146

分形理论与耗散结构、混沌理论一样,是最近一个时期非线性科学研究中所取得的重要成果[1],并在近年来得到了迅速的发展.其主体内容是研究系统的自相似性和不规则性,能为复杂问题的定量化提供新的途径[2].用分形理论研究地质现象是非线性科学的一个重要方向,前人已在地质数据的分形结构、地质时空结构的自相似性及其动力学机制、地质现象的分形重建与矿床分形统计预测方法等方面进行探索,取得了一些重要成果[3～6],但值得指出的是地质分形是统计意义上的无规分形,与数学意义上的严格自相似有区别.  相似文献   

The IOD signal in the upper-ocean Indonesian Throughflow since the mid-1970s     

LAN Jian  SUN Shuangwen  HONG Jieli 《海洋学报(英文版)》2007,26(4):1-6

On the basis of simple ocean data assimilation (SODA) reanalysis product, the interannual variability of upper-ocean Indonesian Throughflow (ITF) volume transport since the mid 1970s is examed. The wavelet analysis shows a second prominent interannual oscillation with a period of about 2~4 a. To reveal any relationship between this band-scale oscillation of upper-ocean ITF and the Indian Ocean dipole (IOD), the correlation and wavelet analyses are used. The correlation coefficient between the upper-ocean ITF and the IOD reaches -0.40 with upper-ocean ITF lagging an IOD index by eight months. The wavelet power spectrum of upper-ocean ITF shows similar structure to that of the IOD index. And the evolution of IOD is reproduced by lagged correlation between the upper-ocean ITF and the sea surface temperature anomaly (SSTA) over the Indian Ocean. It suggests that the 2~4 a band-scale oscillation of upper-ocean ITF is related uniquely to the IOD over the tropical Indian Ocean.  相似文献