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地震海洋学研究进展 总被引：1，自引：0，他引：1
传统船舶调查获取海洋水体温盐资料的方法在水平方向上分辨率较低,而用反射地震探测海洋水体特性的方法--地震海洋学,能有效提高海水温盐资料在水平方向上的分辨率.概述了近5年来地震海洋学的发展过程,重点介绍了地震海洋学方法在海洋锋面观测、水团边界划分、海洋内波分析、中尺度涡旋等方面的研究成果,以及AVO、全波形反演等反射地震处理方法在海洋水体特性研究中的应用.比较了地震海洋学方法与声层析技术、高频声技术等声学方法应用于海洋水体特性研究的异同.并展望了下一步研究工作的重点:①有关地震反射剖面的各种参数与海洋水体温盐结构物理模型的联系及其定量分析;②以研究海洋水体特性为目标的地震反射剖面的处理方法;③海洋地震调查历史数据的应用. 相似文献
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大洋环流模式的温盐表面边界条件处理及其影响研究评述 总被引：5，自引：0，他引：5
对常用的大洋环流模式温度和盐度的表面边界条件处理方案进行了总结,在此基础上,讨论了不同处理方案对大洋环流变化模拟结果的影响,指出了不同边界条件各自的适用范围。较为典型的温度边界条件包括Haney型边界条件、Rahmstorf等恢复型边界条件、Schopf零热容量条件以及通量条件;盐度边界条件主要包括恢复型边界条件、通量型边界条件以及自然边界条件。边界处理方案之不同,不仅影响到模式气候态和年际变率的模拟,还影响到一些典型大洋环流变化现象的模拟结果,如极地盐跃层突变现象、海洋层结强烈翻转的冲刷现象、热盐环流的多平衡态现象以及淡水冲击对热盐环流的影响等问题。 相似文献
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北极海冰与全球气候变化 总被引：7，自引：2，他引：7
最近有关北极海冰在全球气候系统中作用的研究发现，北冰洋边缘海域大洋深水的形成与海冰发育有关，海冰冻融过程对盐度层结具有重要影响，海冰变化可引起盐度突变层的灾变和热盐环流的突然停止，热盐环流的变化与北大西洋海冰１０年际变化相联系，北大西洋气候的不稳定性与热盐环流变化密切相关。北极海冰－海洋－大气间耦合作用，使北极海冰构成了北大西洋和全球气候反馈循环中的重要环节。 相似文献
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北太平洋中层水(NPIW)作为全球海洋经向翻转环流的一个重要组成部分,在区域海洋环境和全球气候变化中扮演着重要角色。本研究对NPIW演化及其对气候变化的影响最新进展进行了评述。认为NPIW形成及通风演化对全球气候变化响应十分敏感。而且高纬气候信号通过这一“海洋通道”传递到北太平洋低纬海域。另一方面,东亚夏季风通过影响黑龙江进入鄂霍次克海的径流量,从而对NPIW的形成和水团组成产生影响。在千年尺度,NPIW通风过程与大西洋经向翻转流(AMOC)呈反相位变化,这与AMOC千年尺度震荡所引发的北太洋海表温、盐变化相关。与NPIW相关的物理过程和生物过程可能是触发冰期大气CO2浓度变化的一个重要机制。 相似文献
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印度尼西亚海与印度尼西亚贯穿流研究概述 总被引：4，自引：1，他引：3
概述过去30年间与印度尼西亚海和印度尼西亚贯穿流有关的海洋动力学方面的研究进展。印度尼西亚海处于海洋大陆的中心地带,衔接西太平洋和印度洋的暖池,是影响大气环流的关键海域;而通过印度尼西亚海多个连通海峡从太平洋进入印度洋的贯穿流,对维持全球大洋热盐分布和平衡起着关键的作用,影响着全球大洋环流的结构及长期的气候变化。基于大... 相似文献
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在上层海洋,受盐度的影响,温度均匀层和密度均匀层并不一定重合,出现温跃层顶界深度明显大于密度跃层顶界深度的现象,即产生盐度障碍层.重力稳定度较高的障碍层对上层海洋热量的垂直交换具有“热障”作用,使混合层和温跃层无法进行有效的热量交换,导致局地海洋上混合层偏暖,从而影响局地海气相互作用乃至全球气候变化.得益于全球海洋观测计划的实施,近20年来科学家已逐渐认识到盐度在海洋环流和气候变化中的重要性,因此盐度障碍层在上层海洋热量收支中的作用等科学问题已成为物理海洋学的前沿研究热点.以障碍层多尺度变异为中心,围绕影响和调控障碍层变异的关键海洋过程,以及障碍层通过海气相互作用影响天气、气候尺度变异的过程和机理等关键科学问题,综述了近几十年来有关热带障碍层的研究进展.重点总结了以下3个方面的进展:全球不同热带海域障碍层的空间结构和多尺度变异特征;海洋动力过程和大气热力过程在障碍层变异中的作用及其机理;障碍层与天气、气候事件及海洋生物相互作用的关键过程和机理.强调了障碍层变异的海洋—大气耦合过程及其气候效应,最后提出了尚需解决的关键科学问题. 相似文献
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阐述了加强我国近海调查研究的重要意义及物理海洋学在海洋学发展中的重要性；提出了需要加强研究的一些重要物理海洋学问题——近岸区研究的重要性、陆坡区的交换过程、陆架“暖流”动力学问题、陆架海气相互作用等。同时指出亟待加强海洋调查研究. 相似文献
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在《印度洋底大地构造图》的基础上,分析了印度洋盆构造格局和洋盆演化重大事件序列,并从印度洋盆初始裂解机制、扩张中心跃迁与热点作用、洋中脊扩展作用等方面讨论了印度洋盆的张开过程,提出以下几点认识:(1)现今印度洋洋中脊可分为两个系统:东南印度洋中脊-中印度洋中脊-卡斯伯格洋脊系统(东支)和西南印度洋中脊系统(西支),前者是太平洋洋中脊扩展作用的产物,后者是太平洋-东南印度洋中脊与大西洋中脊之间构造调节的产物;(2)印度洋盆最初裂解受地幔柱垂向挤压-水平伸展作用控制,沿前寒武造山带等地壳薄弱带发育;(3)印度洋盆经历两次扩张中心的跃迁,其趋向性跃迁方向与热点相对板块的运动方向具有一致性,显示两者存在内在联系。(4)大西洋和太平洋洋中脊在印度洋交汇,于古近纪连通,末端伴随陆块持续发生碎裂化、裂解化,可称为鱼尾构造模式,表明印度洋盆衔接和调节了三大洋盆的发育和演化过程,具有全球洋盆枢纽的关键意义。 相似文献
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2005年夏,一个先进的海洋观测网络——包括实时的光纤海洋观测系统和内部存储的自动化观测系统——被投放在了阿曼海和北阿拉伯海并运行至今.在2010年初,其中的自动化观测系统被升级到了新的深水光纤观测系统.这个海洋观测网络是在阿曼农业和渔业部的资助下,由美国的Lighthouse R&D公司设计、开发、安装和维护的.这2个观测系统作为一个整体已经连续工作了7年多的时间.所采集数据包括海流、温度、盐度、压力、溶解氧和浊度等.该海区是一个多水团的汇合区,波斯湾的高盐水和阿拉伯海的低盐水在这里汇合并蔓延南下到印度洋.对采集的数据研究表明,这一观测网络对研究该区域的物理和生物过程具有重要价值.在此,将系统介绍整个观测网络,并简要阐述已经完成和接近完成的4个研究主题:①对阿拉伯海有记载以来最强热带气旋“古怒”的海洋响应的研究;②阿曼海北部的季节性缺氧现象的季节及年际变化和成因分析;③深海声散射层的时空演变;④阿曼海和北阿拉伯海的高温高盐现象的成因.该观测网络采集的长期、连续的时间序列对这一地区的海洋动力研究、水文的季节性变化,以及气候的长期变化等研究都有很大帮助.此外,如果观测网络可以完成25年的设定观测目标,这将对验证和改进海洋环流模式和海气耦合模式具有重要意义. 相似文献
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The Indian Ocean and the West Pacific Ocean and their ocean-continent connection zones are the core area of "the Belt and Road". Scientific and in-depth recognition to the natural environment, disaster distribution, resources, energy potential of “the Belt and Road” development, is the cut-in point of the current Earth science community to serve urgent national needs. This paper mainly discusses the following key tectonic problems in the West Pacific and North Indian oceans and their ocean-continent connection zones (OCCZs): 1. modern marine geodynamic problems related to the two oceans. Based on the research and development needs to the two oceans and the ocean-continent transition zones, this item includes the following questions. (1) Plate origin, growth, death and evolution in the two oceans, for example, 1) The initial origin and process of the triangle Pacific Plate including causes and difference of the Galapagos and West Shatsky microplates; 2) spatial and temporal process, present status and trends of the plates within the Paleo- or Present-day Pacific Ocean to the evolution of the East Asian Continental Domain; 3) origin and evolution of the Indian Ocean and assembly and dispersal of supercontinents. (2) Latest research progress and problems of mid-oceanic ridges: 1) the ridge-hot spot interaction and ridge accretion, how to think about the relationship between vertical accretion behavior of thousands years or tens of thousands years and lateral spreading of millions years at 0 Ma mid-oceanic ridges; 2) the difference of formation mechanisms between the back-arc basin extension and the normal mid-oceanic ridge spreading; 3) the differentials between ultra-slow dian Ocean and the rapid Pacific spreading, whether there are active and passive spreading, and a push force in the mid-oceanic ridge; 4) mid-oceanic ridge jumping and termination: causes of the intra-oceanic plate reorganization, termination, and spatial jumps; 5) interaction of mantle plume and mid-oceanic ridge. (3) On the intra-oceanic subduction and tectonics: 1) the origin of intra-oceanic arc and subduction, ridge subduction and slab window on continental margins, transform faults and transform-type continental margin; 2) causes of the large igneous provinces, oceanic plateaus and seamount chains. (4) The oceanic core complex and rheology of oceanic crust in the Indian Ocean. (5) Advances on the driving force within oceanic plates, including mantle convection, negative buoyancy, trench suction and mid-oceanic ridge push, is reviewed and discussed. 2. The ocean-continent connection zones near the two oceans, including: (1) Property of continental margin basement: the crusts of the Okinawa Trough, the Okhotsk Sea, and east of New Zealand are the continental crusts or oceanic crusts, and origin of micro-continent within the oceans; (2) the ocean-continent transition and coupling process, revealing from the comparison of the major events between the West Pacific Ocean seamount chains and the continental margins, mantle exhumation and the ocean-continent transition zones, causes of transform fault within back-arc basin, formation and subduction of transform-type continental margin; (3) strike-slip faulting between the West Pacific Ocean and the East Asian Continent and its temporal and spatial range and scale; (4) connection between deep and surface processes within the two ocean and their connection zones, namely the assembly among the Eurasian, Pacific and India-Australia plates and the related effect from the deep mantle, lithosphere, to crust and surface Earth system, and some related issues within the connection zones of the two oceans under the super-convergent background. 3. On the relationship, especially their present relations and evolutionary trends, between the Paleo- or Present-day Pacific plates and the Tethyan Belt, the Eurasian Plate or the plates within the Indian Ocean. At last, this paper makes a perspective of the related marine geology, ocean-continent connection zone and in-depth geology for the two oceans and one zone. 相似文献
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热带太平洋海洋环流与暖池的结构特征、变异机理和气候效应 总被引：3，自引：0，他引：3
热带西太平洋暖池是引发强烈的大气对流、驱动Walker环流和Hadley环流系统的主要热源之一,对全球、尤其是东亚气候有重要影响。针对我国在提升气候预测水平方面的重大和迫切需求,国家重点基础研究发展计划项目"热带太平洋海洋环流与暖池的结构特征、变异机理和气候效应"于2011年7月正式立项。项目拟解决的关键科学问题包括:①调控暖池形成和变异的海洋环流多尺度相互作用过程;②海洋动力过程在暖池热盐结构变异中的作用及其机理;③暖池变异对不同类型El Nio影响机理的异同和对东亚季风变异的调制机理。围绕上述关键科学问题,项目将以暖池变异为中心,关注影响和控制暖池结构与变异的关键海洋过程,以及暖池海气相互作用影响ENSO循环、东亚季风年际变异的过程和机理,重点组织开展以下3个方面有针对性的调查研究:①热带太平洋环流和暖池的结构和变异特征;②热带太平洋环流与暖池相互作用的关键过程和机理;③暖池变异的海洋—大气耦合过程及其气候效应。在此基础上,项目将力争阐明暖池影响东亚季风和我国气候变异的过程、机理与敏感区,改进模式的混合参数化方案,提出有效提高ENSO预报技巧的同化方案,为我国短期气候预测能力的提高提供科学支撑。 相似文献
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In the recent decades， a large amount of anthropogenic heat has been absorbed and stored in the Southern Ocean. Results from observations and climate models' simulations both show that the Southern Ocean displays large warming in the upper and subsurface ocean that maximizes at 45°~40°S. However， the underlying mechanisms and evolution processes of the Southern Ocean temperature changes remain unclear， leaving the Southern Ocean to be a hotspot of climate change studies in the recent years. The present study summarized the current progress in the observations and numerical modeling of long-term temperature changes in the Southern Ocean. The effects of changes in wind， surface heat flux， sea-ice and other factors on the ocean temperature changes were presented， along with the introduction to the role of oceanic mean circulation and eddies. The present study further proposed that a deepening of the understanding in the Southern Ocean temperature change may be achieved by investigating the fast and slow responses of the Southern Ocean to external radiative forcing， which are respectively associated with the fast adjustments of the ocean mixed-layer and the slow evolution of the deep ocean. Specifically， the striking and fast mixed-layer ocean warming north of 50°S is tightly related to the surface heat absorption over upwelling regions and wind-driven meridional heat transport， resulting in enhanced warming around 45°S. While in the slow response of the Southern Ocean temperature， the enhanced ocean warming shifts southward and downward， mainly associating with the heat transfer from oceanic eddies. The Southern Ocean temperature has pronounced climatic effects on many aspects， such as global energy balance， sea-level rise， ocean stratification changes， regional surface warming and atmospheric circulation changes. However， large model biases/deficiencies in simulating the present-day climatology and essential ocean dynamic processes last in generations of climate models， which are the main challenge in advancing our understanding in the mechanisms for the Southern Ocean climate changes. Therefore， to achieve reliable future projections of the Southern Ocean climate， substantial efforts will be needed to improve the model performances and physical understanding in the relative role of various processes in ocean temperature changes at different time scales. 相似文献
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物理海洋观测研究的进展与挑战 总被引：1，自引：0，他引：1
从当今物理海洋所面临的若干前沿科学问题出发,重点探讨了物理海洋观测研究所面临的任务与挑战,包括大洋边界流系统、海洋湍流及跨等密度面混合以及海洋热含量和淡水平衡等.在已有的基础上,对我国在深海研究领域特别是物理海洋观测方面提出了几点针对性的建议. 相似文献
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我国海洋科学领域的全球变化研究进展 总被引：7，自引：3，他引：7
简要介绍了属于海洋科学研究领域中的全球变化研究计划，重点介绍了我国在热带海洋和全球大气（TOGA）、世界大洋环流试验（WOCE）、全球海洋通量联合研究（JGOFS）和海洋PAGES研究中所开展的工作及其研究进展。 相似文献
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CHEN Xuegang YU Mingzhen LOH Peisun Dieter GARBESCH?NBERG Mark SCHMIDT CHEN Chen Tung Arthur ZHENG Hao YE Ying 《《地质学报》英文版》2019,93(Z2):12-13
A group of low‐angle normal faults developed in banded gabbro of Moa Ophiolite, Cuba. The dark gabbro was cut into puddings by several normal faults, while light gabbro was just swelling in layer thickness. In Hongliuhe ophiolite at eastern segment of South Tien Shan Suture Zone in China, the extensional deformation concentrates on fine cumulus gabbro which is typically mylonitized. Abundant structural features were discovered in HLH ophiolite such as S‐C foliation, C’ foliation, extensional crenulation cleavage, small toughness normal fault, low‐angle normal faults and high‐angle normal faults. According to the above tectonic phenomenon from the ophiolite belts in Cuba and China, we will get the conclusion: the maximum principal compressive stress (b1) is vertical to cumulus bedding, and the maximum tensile stress (b3) is paralleling to cumulus bedding. Considering of the above evidence, the extensional tectonic event should developed at mid‐ocean ridge. Due to seafloor spreading, the maximum tensile stress is paralleling to cumulus layer, and extensional tectonic is kept in cumulus gabbro. In this way, normal faults developed in dark gabbro, while brittle‐ductile extensional developed in light gabbro. A large number of domes, folds paralleling to ocean ridge and detachment faults represented by low angle normal fault were discovered near ocean ridge in Indian Ocean and Atlantic Ocean. In this way, materials from deep oceanic lithosphere (e.g. gabbro, mantle peridotite) outcrop at the crust surface of ocean basin. The above evidences from China and Cuba are consistent with extensional tectonic and metamorphic core complex from slowly and super‐slowly spreading Indian Ocean and Atlantic Oceanic lithosphere based on ODP. Therefore, extensional deformation in the ophiolite belt is of significant meaning for clarifying the formation process and mechanism of ancient oceanic basin. 相似文献
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Satellite-derived sea-ice extent in the Indian Ocean Sector during the period November 1978 to December 2006 was studied in
relation to the atmospheric forcing and oceanic thermohaline structure. The study revealed that sea-ice extent increased when
the ocean exhibited higher stability. Low sea-ice extent was observed during 1985 to 1993, when the zonal winds and latent
flux was relatively weak and when the ocean exhibited strong vertical mixing facilitated by low stability thereby, deepening
the mixed layer to ∼250 m. This was reflected in the ocean surface layer temperature, which was relatively warm (−0.3°C).
Winds increased during 1996 to 2000, but due to higher oceanic stability mixed layer depth shallowed (< 200 m) leading to
reduced vertical mixing of deep warmer layers with the surface water, leading to an enhancement in the sea-ice extent. 相似文献
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Pb, Sr AND Nd-ISOTOPIC COMPOSITIONS OF PALEO AND NEO-TETHYAN OCEANIC CRUSTS IN THE EASTERN TETHYAN DOMAIN: IMPLICATION FOR THE INDIAN OCEAN-TYPE ISOTOPIC SIGNATURE 相似文献