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1.
模态水在全球气候变化中有着重要作用.但是由于缺乏海洋次表层的高分辨率观测,对空间尺度为百公里的海洋中尺度涡旋如何影响空间尺度大于千公里的模态水的认识仍然欠缺.为了解决这一科学难题,在科技部的支持下,实施了一次成功的海上观测试验.系统梳理了基于该观测数据所发表的有关涡旋影响模态水潜沉和输运的主要研究成果:①捕捉并揭示了中尺度涡导致混合层水潜沉的过程和动力机制;②发现了中尺度涡携带模态水迁移的新路径;③阐明了模态水多核结构的形成机制.研究结果揭示了黑潮延伸体海域中尺度涡旋影响大尺度模态水的物理本质,为该海域多时空尺度海洋—大气相互作用作出了一定的贡献.通过对该次观测试验结果的分析和总结,得到了如下新的科学推论:海洋次中尺度过程对模态水的形成和耗散也具有重要影响. 相似文献
2.
《地球科学进展》2020,(5)
黑潮延伸体海区是冬季西北太平洋向大气加热的关键海区。前人研究表明活跃在黑潮延伸体海区的海洋涡旋会通过影响海表面温度而影响海面风。回顾了最近几年该海域海洋涡旋影响局地大气的研究成果,重点从船测探空资料、卫星观测资料和模式数值实验3个方面分析和比对了已有的研究成果,依据该海区海洋涡旋导致大气异常的地转适应理论,得到了如下新的科学推论:海洋涡旋上空大气运动较慢时,大气对海洋涡旋的响应表现以气压调整机制为主,海洋涡旋的影响常常被限制在大气边界层中;海洋涡旋上空大气的运动较快时,大气对暖(冷)涡的响应以垂直混合机制为主,海表面风速在暖(冷)水上加(减)速,海表面风强辐合出现在暖水的背景风下游一侧,并从暖水上空携带了大量水汽;通过水汽凝结与海面辐合上升之间的正反馈机制,为导致大气中出现强对流提供了必要条件。该推论将有利于进一步定量刻画海洋涡旋对大气的影响。 相似文献
3.
北太平洋副热带环流变异及其对我国近海动力环境的影响 总被引：1，自引：0，他引：1
我国东部陆架海和南海是国防安全的重要门户;位处第二岛链以西的副热带北太平洋既是各国争夺的重要海区,又是我国从近海走向大洋的重要通道.围绕"北太平洋副热带环流变异如何通过黑潮与我国近海动力环境之间相互作用"这一国际前沿科学问题,国家重点基础研究发展计划项目"北太平洋副热带环流变异及其对我国近海动力环境的影响"于2007年9月正式立项.该项目不仅有助于拓展和丰富海洋动力学理论,揭示我国近海及邻近大洋动力环境变异机制,提高预测能力,而且也将为维护我国国防安全和海洋权益,为可持续开发利用海洋资源提供海洋动力环境保障.该项目主要研究内容包括:①北太平洋副热带环流变异和调整机理;②黑潮与我国近海的能量与水体交换过程及机制;③北太平洋副热带环流变异与大气驱动力的耦合效应;④我国近海及邻近大洋动力环境变异的可预测性研究.拟解决的关键科学问题为:北太平洋副热带内区环流变异的机理及其对黑潮的影响;黑潮源头变异机理及其对吕宋海峡水交换的影响和黑潮变异机理及其对东部陆架海域动力环境的影响. 相似文献
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5.
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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我国太平洋深海沉积研究综述 总被引：1，自引：0，他引：1
总结了我国对太平洋深海沉积物组成、分布、形成及深海沉积中宇宙尘、海洋沉积通量、铁锰结核的研究成果,指出了在全球变化研究中太平洋深海沉积的研究课题。 相似文献
8.
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
9.
大气沉降对海洋初级生产过程与氮循环的影响研究进展 总被引：4，自引：1，他引：3
大气沉降通过为海洋提供外源性氮、磷和铁等微量元素,可显著影响海洋氮、碳循环过程,并产生气候效应。一方面促进海洋初级生产和生物固氮,增强海洋吸收二氧化碳的能力;另一方面影响海洋氮、碳循环路径,增加海洋生物源气溶胶排放量,间接影响气候变化。由于大气沉降对海洋生态系统及气候变化的重要影响,相关科学问题已成为海洋科学与大气科学交叉研究的热点,被多个国际研究计划列为核心研究内容。在大气污染物排放持续增加与沙尘事件频发的背景下,大气沉降对我国东部陆架海(黄海、东海)及其邻近西北太平洋碳、氮循环过程的影响日趋增强,因此该海区已成为大气沉降及其气候影响研究的代表性海域。结合分子生物学和实验生态学手段理解大气沉降影响下的海洋初级生产过程,利用同位素示踪技术研究大气沉降对海洋氮循环的影响,以及获得大气沉降影响下海洋生物源气溶胶排放的观测证据将是未来研究的重点方向。 相似文献
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11.
The Kuroshio Extension （KE） is the key area where the water heats the atmosphere in the northwestern Pacific Ocean in winter. Previous studies show that the active eddies in the KE area can affect sea surface temperature and thus sea surface winds. The present study reviewed the progress about the influences of the eddies on local atmosphere in recent years. Analysis and comparison were made especially for the achievements from shipboard sounding data, satellite observations and numerical experiments. Based on the geostrophic adaptation theory involved in atmospheric anomalies induced by the eddies, the following new scientific deductions were suggested: Air pressure adjustment mechanism dominated in the atmospheric response to eddies under the conditions of weaker wind speed over the eddies. The influence of eddies was often limited in the atmospheric boundary layer. On the other hand, vertical mixing mechanism played a major role in the response of the atmosphere to warm (cold) eddies when air moved faster over the eddies. Surface wind speed increased (decreased) over the warm (cold) water. Significant wind convergence took place downwind the warm water, and large amount of water vapor was transported also downwind from the warm water surface. The positive feedback between water vapor condensation and rising air forced by the surface convergence provided necessary conditions for the development of strong convection in atmosphere. These deductions will be conducive to further depicting the impact of oceanic eddies on the atmosphere quantitatively. 相似文献
12.
As one of the most important mesoscale ocean features, the mesoscale eddies are omnipresent and have significant impact on the overlying atmosphere. Based on the comprehensive review of the influence of mesoscale eddies on the atmospheric boundary layer and the local circulation, the corresponding physical mechanisms and their impacts on weather systems were presented systematically. ①Eddy-induced SST anomalies may modify the surface wind speed, horizontal divergence, cloud and precipitation through turbulence heat flux anomalies. Meanwhile, additional secondary circulations arise over the eddies. What is more, there are obvious regional and seasonal differences for atmospheric responses. ② Studies in the South China Sea, the Kuroshio Extension region and the Southern Ocean indicate that atmospheric responses to mesoscale eddies can be explained by the changes of sea level pressure or the vertical momentum transport. These two mechanisms can be distinguished by the phase relationship between the atmospheric anomaly center and the eddy core. Diagnosis on the inner dynamical processes may draw better conclusions. ③The energy conversions are affected by mesoscale eddies, which may affect storm tracks and jet streams, and finally result in distant influences on weather patterns. Moreover, sea temperature anomalies from sea surface to the thermocline associated with mesoscale eddies have significant impacts on the intensification and the maintenance of tropical cyclones. 相似文献
13.
Numerical studies on the influence of the variations of the Kuroshio Path on the transport of fish eggs and larvae 总被引：2，自引：0，他引：2
Main spawning and nursery grounds of the Pacific Sardine are formed in the coastal boundary regions of the Kuroshio S of Kyushu
and S of Honshu, respectively. Numerical experiments on the transport and dispersion of particles in and neighbouring areas
of the Kuroshio were done to investigate the transport process of the fish eggs and larvae from the spawning ground to the
downstream nursery ground. Surface currents measured with GEK in the past were averaged for both paths with and without large
meanders of the Kuroshio in the S of Honshu and used as the data basis. Particles were released in the Kuroshio SE of Kyushu.
The results show that the transport rate of them into the S coastal waters of Honshu during large meandered path is larger
than the rate during the straight path period. However, recruitment rates of the Pacific Sardine in the S coastal waters of
Honshu decreases during the large meander periods of the Kuroshio path. This inverse correlation is considered to be caused
by the poorer food environment strongly influenced by the intrusion of the Kuroshio water. 相似文献
14.
Nie Hongtao Wang Rui Zhao Wei Luo Xiaofan Qi Di Lu Youyu Zhang Yuanhui Wei Hao 《地球科学进展》2017,32(10):1084-1092
Challenged by the enormous pressure to reduce the global carbon emission, it is expected that the Arctic Ocean could absorb additional atmospheric CO2 with the retreating of sea-ice. The Chukchi Sea and adjacent waters, characterized by the highest carbon fixation in the global ocean and large carbon flux into the deep-ocean for sequestration, make substantial contributions to carbon cycling in the entire Arctic Ocean. Understanding the response mechanism of carbon cycling in this region to the rapidly changing environment is the foundation for the prediction of carbon sink in the Arctic Ocean. However, the response of carbon absorption and storage to climate change is still controversial, and the main controlling factors of the carbon cycle process remain unclear.Thus, to establish high-resolution coupled ocean-ice-carbon models can explore the influence of sea ice retreat on atmospheric CO2 and the vertical sinking carbon fluxes in Chukchi Sea, estimate the effectiveness of growing inflow and slope upwelling on carbon sink/source patterns, discuss the response of deep-ocean carbon sequestration to the changing environment, and evaluate the effectiveness of continental shelf pump in the Chukchi Sea as well as its role in the global carbon sink. Based on the challenge for the research of the Chukchi Sea carbon cycle research with rapidly changing climate, the basic ideas of establishing Arctic Ocean carbon cycling model as well as its key scientific issues to be resolved were proposed. 相似文献
15.
Hiroshi Amakawa Yoshiyuki Nozaki Jing Zhang Hisao Nagai 《Geochimica et cosmochimica acta》2004,68(4):715-727
Four vertical profiles of the concentration and isotopic composition of Nd in seawater were obtained in the western North Pacific. Two profiles from the Kuroshio Current regime showed congruently that although the Nd concentration increases gradually with depth, its isotopic composition varies significantly with depth depending upon the water mass occupying the water column. The high-salinity Kuroshio waters originating from the North Pacific Tropical Water (NPTW) carry the least radiogenic Nd (?Nd = −7.4 to −8.7) to this region at ∼250 m from the western margin continental shelves, most likely from the East China Sea. The Nd isotopic compositions in the North Pacific Intermediate Water (NPIW) that occurs at 600 to 1000 m in the subtropical region are fairly uniform at ?Nd = −3.7. The profile data from the ∼38° to 40°N Kuroshio/Oyashio mixed water region off Sanriku of Honshu, Japan, also suggest that the newest NPIW with ?Nd = −3.2 is formed there by the mixing of various source waters, and the radiogenic component of Nd is derived mainly from the Oyashio waters.In the Pacific Deep Water (PDW) below ∼1000 m, the Nd isotopic composition is neither vertically nor horizontally homogeneous, suggesting that it serves as a useful tracer for sluggish deep water circulation as well. Two profiles from the Izu-Ogasawara Trench showed a minimum ?Nd value at ∼2000 m, suggesting that there exists a horizontal advective flow in the vicinity of Honshu, Japan. There is some evidence from other chemical properties to support this observation. The waters below 4000 m including those within the trench in the subtropical region have ?Nd values of around −5, suggesting that the deep waters are fed from the south along the western boundary, ultimately from the Antarctic Bottom Water (AABW) in the South Pacific. This extends up to ∼40°N along the Japanese Islands. In the subarctic region (>∼42°N), the waters have more radiogenic Nd with ?Nd > −4.0 throughout the water column, presumably due to the supply of Nd by weathering in such igneous provinces as the Kuril-Kamchatska-Aleutian Island chain. The lateral inhomogeneity of the Nd isotopic composition in PDW suggests that there may be different circulation and mixing regimes in the North Pacific Basin. 相似文献
16.
The vertically averaged temperature (Tav) over the upper 200 m of ocean in the W boundary of the N Pacific is used to detect changes in the strenght and path of the
Kuroshio Front along the W boundary from Luzon (18° N) to Honshu (34° N) during the period, 1979–1982. During this time period
the Kuroshio Front experienced significant interannual changes associated, both with the disappearance of the Kuroshio Meander
in late 1980 and with the development of the 1982 ENSO event in early 1982. When the Kuroshio Meander S of Honshu disappeared
in the fall of 1980, lasting until the summer of 1981, the intensity of the Kuroshio Front increased, associated with warmer
than normal temperatures all along the W boundary of the N Pacific from Luzon to Honshu. The amplitude of the Kuroshio Meander
was also correlated with fluctuations in the path of the Kuroshio Front at the Tokara Strait (30° N) and the Bashi Strait
(20° N), and with the amplitude of the East China Sea Meander. The East China Sea Meander occurs W of the Ryukyu Islands at
25° N, formed when the Kuroshio Current enters the East China Sea from the Philippine Sea NE of Taiwan Island. It had large
amplitude in winter and smaller amplitude in spring and early summer, similar to that in the Kuroshio Meander when it was
present during this period. It also had related interannual variability; i.e., when the Kuroshio Meander disappeared in fall
of 1980, the East China Sea Meander was weak. These results and earlier ones dealing with the Kuroshio Front E of Japan (e.g.,
White and He) indicate that fluctuations in the amplitude of the Kuroshio Meander S of Honshu were associated with similar
changes in the meandering character over the entire Kuroshio Current System during this four year period.
During the 1982 ENSO event, the temperature in the region of the Kuroshio Front in the W boundary became colder than normal,
while the Kuroshio Meander S of Honshu and the East China Sea Meander NE of Taiwan Island developed larger amplitudes. This
is consistent with the results of White and He, who found during this same time period that the mesoscale meander pattern
in the Kuroshio Extension intensifying during the 1982 ENSO period. During this time, the magnitude of the Kuroshio Front
all along the W boundary and in the Kuroshio Extension region was weaker in comparison with the three years prior to the 1982
ENSO event. 相似文献
17.
黑潮与毗邻陆架海域的碳交换 总被引：2，自引：0，他引：2
作为沟通陆架边缘海与开放大洋的北太平洋西边界流,黑潮对毗邻中国陆架海域碳循环有着不可忽视的影响。分析总结了黑潮与毗邻陆架海域海水中溶解有机碳(DOC)、颗粒有机碳(POC)、溶解无机碳(DIC)和颗粒无机碳(PIC)分布与交换的现有研究成果。分析表明,黑潮通过表层水涡旋、入侵以及次表层以下水体上涌等形式携碳进入毗邻陆架海域。在黑潮与毗邻陆架海域,DOC和POC的分布受生物活动、水团混合以及沉积物—水界面相互作用的共同影响,表层与陆架水中含量较高,DIC受海水碳酸盐体系平衡影响,表层含量低于底层,在陆架海域与上升流区有高值,PIC含量较低。在台湾东北海域,DOC,POC和DIC由东海陆架海域向黑潮有净输出,输出量分别为2 431×109,1 051×109和21 733×109mol C/a,PIC通过陆架源悬浮颗粒物向黑潮主流输送,通量为1 852×109mol C/a。DOC,POC和PIC由南海经吕宋海峡向黑潮有净输出,输出量分别为2 652×109,1 009×109和230×109mol C/a,但DIC由黑潮向南海有净输出,通量为13 005×109mol C/a。台湾海峡碳循环受黑潮输运的影响,但影响机制及过程至今并不清楚。因此,黑潮与毗邻陆架海域的碳交换过程研究还有若干重大科学问题亟待解决,尚需深入系统的研究。 相似文献
18.
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
19.
Mesoscale eddies are active and energetic in the South China Sea (SCS), and play an important role in regulating the multi-scale circulation and mass transportation in the region, especially for those long-lived strong eddies. Using AVISO altimeter data and outermost closed contour sea level anomaly method, this study identified and tracked mesoscale eddies in the northern SCS during 2011-2018, and focused on the temporal and spatial characteristics of mesoscale eddies in recent years. Similarly to previous results in this region, statistical results show that about 8.6 anticyclonic eddies and 4.5 cyclonic eddies (lifetime > 28 days) were born per year. Among them, about 1/3 of the total number are strong eddies (lifetime > 45 days), showing relatively strong dynamic characteristics, such as strong Eddy Kinetic Energy (EKE) and highly nonlinear feature. Statistics also show significant seasonal variability in mesoscale eddies’ birth places, trajectories and distribution of frequency of occurrence. Specifically, anticyclonic eddies mainly form at the north part of Luzon Strait between autumn and winter, and then move southwestward along isobaths. During this period, the largest value of the frequency of occurrence is over 30%. In summer, most of them form in the west off Luzon Island, and then move westward paralleling to latitude lines. In contrast, cyclonic mainly form in the west off Luzon Strait, and then move westward in winter and spring. During this period, the largest value is about 26%. In addition, observation finds that the strong mesoscale eddy pair could generate off the southwest of Taiwan Island. Analysis of the Kuroshio SCS Index (KSI) implies that loop current caused by Kuroshio intrusion is the most important mechanism for the formation of eddy pair. 相似文献
20.
利用美国国家环境保护委员会/国家大气研究中心(NCEP/NCAR)再分析气候资料,分析了西风带与季风对我国西北地区水汽输送的作用。分析表明,大气水汽输送在西北地区的3个分区特征非常明显:高原切变线以南,主要是来自西南季风的水汽输送;高原切变线以北,主要是来自西风带的水汽输送;高原切变线向东北方向的延长部位是一鞍型区,为西风带与西南季风的共同影响区。青藏高原东部的西南季风气流有绕行和向北翻越青藏高原的水汽输送;而在青藏高原中西部地区,主要是由青藏高原周边向主体的水汽输送,没有明显的翻越青藏高原的水汽输送。在青藏高原以北的大部分地区以对流层中层的水汽输送为主;在青藏高原南部以低层水汽输送为主。在青藏高原以北的大部分地区,水汽输送为辐散,即输入的水汽又被扩散出去了;在青藏高原主体和我国西北地区东部为水汽输送的辐合区。西风带的水汽输送为我国西北大部分地区提供了基本的水汽来源,西风变化对其水汽输送通量散度年际变化有直接的作用;南亚夏季风通过西南季风气流水汽输送直接影响我国西北地区南部和东部,并且,其变化通过环流结构调整影响西风带的波动,进而影响西风带对西北地区的水汽输送。 相似文献