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1.
中国物理海洋学研究70年:发展历程、学术成就概览   总被引:2,自引:2,他引:0  
本文概略评述新中国成立70年来物理海洋学各分支研究领域的发展历程和若干学术成就。中国物理海洋学研究起步于海浪、潮汐、近海环流与水团,以及以风暴潮为主的海洋气象灾害的研究。随着国力的增强,研究领域不断拓展,涌现了大量具有广泛影响力的研究成果,其中包括:提出了被国际广泛采用的“普遍风浪谱”和“涌浪谱”,发展了第三代海浪数值模式;提出了“准调和分析方法”和“潮汐潮流永久预报”等潮汐潮流的分析和预报方法;发现并命名了“棉兰老潜流”,揭示了东海黑潮的多核结构及其多尺度变异机理等,系统描述了太平洋西边界流系;提出了印度尼西亚贯穿流的南海分支(或称南海贯穿流);不断完善了中国近海陆架环流系统,在南海环流、黑潮及其分支、台湾暖流、闽浙沿岸流、黄海冷水团环流、黄海暖流、渤海环流,以及陆架波方面均取得了深刻的认识;从大气桥和海洋桥两个方面对太平洋–印度洋–大西洋洋际相互作用进行了系统的总结;发展了浅海水团的研究方法,基本摸清了中国近海水团的分布和消长特征与机制,在大洋和极地水团分布及运动研究方面也做出了重要贡献;阐明了南海中尺度涡的宏观特征和生成机制,揭示了中尺度涡的三维结构,定量评估了其全球物质与能量输运能力;基本摸清了中国近海海洋锋的空间分布和季节变化特征,提出了地形、正压不稳定和斜压不稳定等锋面动力学机制;构建了“南海内波潜标观测网”,实现了对内波生成–演变–消亡全过程机理的系统认识;发展了湍流的剪切不稳定理论,提出了海流“边缘不稳定”的概念,开发了海洋湍流模式,提出了湍流混合参数化的新方法等;在海洋内部混合机制和能量来源方面取得了新的认识,并阐述了混合对海洋深层环流、营养物质输运等过程的影响;研发了全球浪–潮–流耦合模式,推出一系列海洋与气候模式;发展了可同化主要海洋观测数据的海洋数据同化系统和用于ENSO预报的耦合同化系统;建立了达到国际水准的非地转(水槽/水池)和地转(旋转平台)物理模 型实验平台;发展了ENSO预报的误差分析方法,建立了海洋和气候系统年代际变化的理论体系,揭示了中深层海洋对全球气候变化的响应;初步建成了中国近海海洋观测网;持续开展南北极调查研究;建立了台风、风暴潮、巨浪和海啸的业务化预报系统,为中国气象减灾提供保障;突破了国外的海洋技术封锁,研发了万米水深的深水水听器和海洋光学特性系列测量仪器;建立了溢油、危险化学品漂移扩散等预测模型,为伴随海洋资源开发所带来的风险事故的应急处理和预警预报提供科学支撑。文中引用的大量学术成果文献(每位第一作者优选不超过3篇)显示,经过70年的发展,中国物理海洋学研究培养了一支实力雄厚的科研队伍,这是最宝贵的成果。这支队伍必将成为中国物理海洋学研究攀登新高峰的主力军。  相似文献   
2.
ABSTRACT

We investigated the oceanic crustal structure and lithospheric dynamics of the South China Sea (SCS) basin through a comprehensive analysis of residual gravity anomaly and bathymetry combined with seismic constraints and interpretation from geodynamic modelling. We first calculated the residual mantle Bouguer anomaly (RMBA) of the oceanic crustal regions of the SCS by removing from free-air gravity anomaly the predicted gravitational attractions of water-sediment, sediment-crust, and crust-mantle interfaces, as well as the effects of lithospheric plate cooling, using the latest crustal age constraints including IODP Expedition 349 and recent deep-tow magnetic surveys. We then calculated models of the gravity-derived crustal thickness and calibrated them using the available seismic refraction profiles of the SCS. The gravity-derived crustal thickness models correlate positively with seismically determined crustal thickness values. Our analysis revealed that the isochron-averaged RMBA are consistently more negative over the northern flank of the SCS basin than the southern conjugate for magnetic anomaly chrons C8n (~25.18 Ma) to C5Dn (~17.38 Ma), implying warmer mantle and/or thicker crust over much of the northern flank. Computational geodynamic modelling yielded the following interpretations: (1) Models of asymmetric and variable spreading rates based on the relatively high-resolution deep-tow magnetic analysis would predict alternating thicker and thinner crust at the northern flank than the southern conjugate, which is inconsistent with the observed systematically thicker crust on the northern flank. (2) Models of episodic southward ridge jumps could reproduce the observed N-S asymmetry, but only for crustal age of 23.6–20 Ma. (3) Southward migration of the SCS ridge axis would predict slightly thinner crust at the northern flank, which is inconsistent with the observations. (4) Models of higher mantle temperatures of up to 25–50°C or >2% less depleted mantle sources on the northern flank could produce large enough anomalies to explain the observed N-S asymmetries.  相似文献   
3.
Ma  Wentao  Xiu  Peng  Chai  Fei  Li  Hongliang 《Ocean Dynamics》2019,69(8):955-966
Ocean Dynamics - The South China Sea (SCS) is strongly influenced by the East Asian monsoon system with seasonal reversal. Measurements from a 7-year continuous sediment trap located in the central...  相似文献   
4.
Chen  Huan-Huan  Qi  Yiquan  Wang  Yuntao  Chai  Fei 《Ocean Dynamics》2019,69(11):1387-1399

Fourteen years (September 2002 to August 2016) of high-resolution satellite observations of sea surface temperature (SST) data are used to describe the frontal pattern and frontogenesis on the southeastern continental shelf of Brazil. The daily SST fronts are obtained using an edge-detection algorithm, and the monthly frontal probability (FP) is subsequently calculated. High SST FPs are mainly distributed along the coast and decrease with distance from the coastline. The results from empirical orthogonal function (EOF) decompositions reveal strong seasonal variability of the coastal SST FP with maximum (minimum) in the astral summer (winter). Wind plays an important role in driving the frontal activities, and high FPs are accompanied by strong alongshore wind stress and wind stress curl. This is particularly true during the summer, when the total transport induced by the alongshore component of upwelling-favorable winds and the wind stress curl reaches the annual maximum. The fronts are influenced by multiple factors other than wind forcing, such as the orientation of the coastline, the seafloor topography, and the meandering of the Brazil Current. As a result, there is a slight difference between the seasonality of the SST fronts and the wind, and their relationship was varying with spatial locations. The impact of the air-sea interaction is further investigated in the frontal zone, and large coupling coefficients are found between the crosswind (downwind) SST gradients and the wind stress curl (divergence). The analysis of the SST fronts and wind leads to a better understanding of the dynamics and frontogenesis off the southeastern continental shelf of Brazil, and the results can be used to further understand the air-sea coupling process at regional level.

  相似文献   
5.
偏振激光雷达探测大气—水体光学参数廓线   总被引:2,自引:2,他引:0  
激光雷达在上层水体垂直廓线的遥感中展现出巨大优势。本文研制了一套高垂直分辨率的实时探测偏振激光雷达,提出了一种基于偏振激光雷达回波信号的反演算法,采用Fernald理论和多次散射原理反演非均匀大气—水体的衰减和退偏光学产品,以高效稳定地处理偏振激光雷达实验数据。展示了一个中国内陆水体激光雷达探测实例,观测到了两次气溶胶积聚现象和一次水体浑浊现象。对实验数据的分析表明,退偏比主要由前向多次散射和后向单次散射产生的退偏两部分组成。当多次散射强度较大时,退偏比的变化主要取决于多次前向散射退偏;反之,则主要依赖于单次后向散射退偏。  相似文献   
6.
杭州湾中部实测波浪特性分析   总被引:1,自引:0,他引:1  
利用杭州湾中部一年实测波浪资料,分析该地区的波参数统计变化特性,采用最小二乘法拟合得出相关参数之间的关系式,并统计分析了频谱特性。结果表明:杭州湾中部以小浪和轻浪为主,在各月分布较为均匀,年平均周期为2.97 s;最大一次波浪过程为冷空气影响所致,影响强度大于台风莫拉克;常浪向分布在东北至东南向,其中又以小浪出现较多,对应的波周期以2~4 s为主;强浪向主要分布在西北和东北方向,对应的波周期主要分布在3~5 s;多数特征波参数之间相关关系较好;由谱分析得知风浪占多数,且以单峰为主。研究结果可为相关工程和理论研究提供基础资料。  相似文献   
7.
The ultraslow-spreading Southwest Indian Ridge(SWIR) to the east of the Melville fracture zone is characterized by very low melt supply and intensive tectonic activity. Due to its weak thermal budget and extremely slow spreading rate, the easternmost SWIR was considered to be devoid of hydrothermal activity until the discovery of the inactive Mt. Jourdanne hydrothermal field(27°51′S, 63°56′E) in 1998. During the COMRA DY115-20 cruise in2009, two additional hydrothermal fields(i.e., the Tiancheng(27°51′S, 63°55′E) and Tianzuo(27°57′S, 63°32′E)fields) were discovered. Further detailed investigations of these two hydrothermal sites were conducted by Chinese manned submersible Jiaolong in 2014–2015. The Tiancheng filed can be characterized as a lowtemperature(up to 13.2°C) diffuse flow hydrothermal field, and is hosted by fractured basalts with hydrothermal fauna widespread on the seafloor. The Tianzuo hydrothermal field is an inactive sulfide field, which is hosted by ultramafic rocks and controlled by detachment fault. The discovery of the three hydrothermal fields around Segment #11 which receives more melt than the regional average, provided evidence for local enhanced magmatism providing heat source to drive hydrothermal circulation. We further imply that hydrothermal activity and sulfide deposits may be rather promising along the easternmost SWIR.  相似文献   
8.
海滩对风暴的响应及风暴后海滩的恢复过程一直以来都是国内外海滩研究的热点。本文通过对浙江舟山市朱家尖岛东沙海滩地形地貌的现场调查,对比分析了热带风暴"娜基莉"影响下东沙海滩剖面的蚀积变化,探讨了海滩在热带风暴发生后的恢复情况。结果表明,在"娜基莉"影响期间,因风暴浪为向岸浪,东沙海滩几乎遭受全线侵蚀,12个剖面单宽侵蚀总量为73.46 m3/m,其中海滩直线段较两个遮蔽段侵蚀显著。由于海滩在风暴前进方向的左侧,且"娜基莉"距东沙较远,使得东沙海滩普遍侵蚀但强度较小。东沙海滩在热带风暴后的恢复过程中,不同部位的地貌调整和冲淤变化不同,下岬角遮蔽段基本趋于稳定,直线段和上岬角遮蔽段在恢复过程中因受海滩季节性调整的影响呈现持续侵蚀。  相似文献   
9.
由于侧扫声纳应用领域不断扩大,用户要求不断提高,国际海道测量组织和世界测量技术发达国家相继发布了各自的新版测量规范和标准。本文将我国侧扫声纳现行测量标准与国际相关标准在系统探测能力、测线布设、数据采集、质量控制等方面进行比较详细的分析比较,指出了我国侧扫声纳测量规范在测线布设、数据采集要求等方面的不足,旨在推进我国测量标准尽快实现与国际接轨。  相似文献   
10.
We present a new reconstruction of summer sea‐surface salinity (SSS) over the past 15 000 years based on a diatom record from piston core 17940, located on the northern slope of the South China Sea (SCS). The reconstructed diatom‐based summer SSS values for the modern period are in accord with instrumental observations of summer SSS in the area. Here, the modern summer SSS is primarily controlled by river runoff, in particular from the Pearl River. The reconstruction presented in this study shows that the summer SSS varied between 33.3 and 34.2 psu over the past 15 000 years. The long‐term summer SSS trend closely followed the trend of the orbitally controlled solar insolation at 20°N, suggesting that orbital forcing was the dominant driver of changes in summer SSS in this area. Comparisons to speleothem δ18O data and studies of surface hydrography in the region suggest that changes in solar insolation affected the summer SSS through changes in the East Asian Monsoon and sea‐level changes associated with the last deglaciation. Univariate spectral analyses indicate that centennial‐scale oscillatory variations in summer SSS were superimposed on the long‐term trend. During the deglacial period (c. 12 000–9000 cal. a BP), the dominant periodicity was centred around 230–250 years, whereas a ~350‐year oscillation dominated in the period 2200–4500 cal. a BP. The balance of evidence suggests that these centennial‐scale changes in summer SSS may have been driven by solar‐induced changes in the East Asian Monsoon, but further evidence is needed to firmly establish this relationship.  相似文献   
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