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1.
水下滑翔机作为一种新型移动观测平台,可以对热带气旋过境期间引发的海洋响应进行全方位的观测,利用获取的观测数据能够进一步增强台风预报的准确性。从水下滑翔机相较于其他热带气旋观测方式的优势展开,基于“海燕”系列水下滑翔机观测到的台风“天鸽”(Hato)引起的海洋温盐异常历史数据, 并结合同期卫星的观测数据和 JMA(Japan Meteorology Agency)最佳台风路径数据库,分析研究水平和垂直方向上的海洋温盐异常响应。验证了 4 台“海燕–II”水下滑翔机具有对 2017 年台风“天鸽”引起的海洋响应进行精细化剖面观测的能力,可以完整捕捉台风过境引起的垂直混合现象以及降雨对其观测区域内盐度变化的影响,并分析水下滑翔机观测数据得出台风期间海洋响应的程度与其距离台风的位置有关,即台风期间水下滑翔机观测海域与台风路径距离越近,其温盐异常变化越明显,并且台风路径右侧海域相较于路径左侧海域的温度异常幅度更大。 相似文献
2.
依据再分析的海洋温度、盐度月平均资料和观测的热通量资料,确定了北太平洋中纬度晚冬海表温度(SST)持续异常现象较明显的海域是位于38°-42°N,158°E-172°W的西部海域和位于35°-42°N,172°W-145°W的东部海域.分析结果表明,西部海域,晚冬SST持续异常现象的主要机制是海洋上混合层的"再现机制";而东部海域晚冬SST的持续异常现象主要是海面净热通量的持续异常所致.由于冬季北太平洋西风异常导致的上混合层深度季节的差异在1976年前后的不同,1976年后晚冬混合层深度深,"再现机制"的作用明显,SST持续异常现象更容易出现. 相似文献
3.
使用水块混合层模式模拟上层海洋的季节变化 总被引：3，自引：0，他引：3
使用块体混合模式对一个固定海洋观测站所测的上层海洋之物理特性进行了模拟，结果发出了难以重复观测到的许多物理特征。文章提出了水块混合层模式，着重模拟了扩展湾流体系中的一个水块，在它被海流从佛罗里达海峡带到挪威海的过程中，其物理特性（其中包括温度、盐度、混合层深度和夹卷速度）随时间的变化，模拟结果较好地再现了所观测的物理特性的演化。 相似文献
4.
使用块体混合层模式对一个固定海洋观测站所测的上层海洋之物理特性进行了模拟，结果发现了难以重复观测到的许多物理特征。文章提出了水块混合层模式，着重模拟了扩展湾流体系（ＥＧＳＳ）中的一个水块，在它被海流从佛罗里达海峡（２４°Ｎ，８０°Ｗ）带到挪威海（６８°Ｎ，１０°Ｅ）的过程中，其物理特性（其中包括温度、盐度、混合层深度和夹卷速度）随时间的变化。模拟结果较好地再现了所观测的物理特性的演化。 相似文献
5.
《中国海洋大学学报(自然科学版)》2021,(12)
为了进一步认识上层海洋中混合层和障碍层的时空变化特征。本文基于Argo (Array for real-time geostrophic oceanography)海洋观测网2007—2018年的温盐数据,使用差值法计算了全球海洋混合层深度(Mixed layer depth, MLD)和障碍层厚度(Barrier layer thickness, BLT),讨论了二者的月均值、季节均值和年均值的空间分布特征和形成机制。研究表明,全球海洋的混合层普遍在夏季浅、在冬季深,随季节变化的特征显著。北半球混合层变化幅度较大,大西洋混合层比同纬度的太平洋深;赤道海区混合层较浅;南半球混合层呈纬向带状分布,60°S附近大洋海域存在显著的深混合层带,南极大陆与该深混合层带之间的海域混合层常年较浅。全球障碍层呈"哑铃状"分布,两半球的高纬度海区是障碍层高发区,障碍层不仅厚且持续时间长,以半年为周期变化,南大洋60°S附近海域显著的厚障碍层带随季节变化;南半球中低纬度海区长期存在障碍层,障碍层冬厚夏薄,且厚度大部分不超过40 m。 相似文献
6.
基于政府间气候变化专门委员会(Intergovernmental Panel on Climate Change,IPCC)4种最新辐射强迫情景,利用ECHAM5/MPI-OM(European Centre Hamburg Model 5/Max Planck Institute Ocean Model)气候模式输出的1850—2300年逐月混合层深度、海表面温度、海表面盐度数据,分析大西洋热盐环流下沉区混合层深度的变化情况。结果表明:随辐射强迫增加,热盐环流下沉区混合层深度下降,混合层深度振荡周期在格陵兰-冰岛-挪威海(Greenland Sea–Iceland Sea–Norwegian Sea,GIN)海域减小,在拉布拉多海(Labrador Sea,LAB)海域变化不大;与GIN海域相比,LAB海域混合层深度对辐射强迫变化更敏感;两海区温度对混合层深度的影响时间较长,混合层深度对盐度的变化反应迅速;混合层深度变化的主导因素在LAB海域中为盐度,而在GIN海域,低辐射强迫下温度主导混合层深度变化,中高辐射强迫下温度与盐度共同起主导作用。 相似文献
7.
基于政府间气候变化专门委员会(Intergovernmental Panel on Climate Change,IPCC)4种最新辐射强迫情景,利用ECHAM5/MPI-OM(European Centre Hamburg Model 5/Max Planck Institute Ocean Model)气候模式输出的1850—2300年逐月混合层深度、海表面温度、海表面盐度数据,分析大西洋热盐环流下沉区混合层深度的变化情况。结果表明:随辐射强迫增加,热盐环流下沉区混合层深度下降,混合层深度振荡周期在格陵兰-冰岛-挪威海(Greenland Sea–Iceland Sea–Norwegian Sea,GIN)海域减小,在拉布拉多海(Labrador Sea,LAB)海域变化不大;与GIN海域相比,LAB海域混合层深度对辐射强迫变化更敏感;两海区温度对混合层深度的影响时间较长,混合层深度对盐度的变化反应迅速;混合层深度变化的主导因素在LAB海域中为盐度,而在GIN海域,低辐射强迫下温度主导混合层深度变化,中高辐射强迫下温度与盐度共同起主导作用。 相似文献
8.
过去对南大洋的研究受限于长期观测的缺乏,而现在地转海洋学实时观测阵(Arrayfor Real-timeGeostrophicOceanography,Argo)项目自开始以来持续提供了高质量的温度盐度观测,使系统地研究南大洋海洋上层结构成为可能。本研究使用2000—2018年的Argo浮标观测数据,分析了南大洋混合层深度(Mixed Layer Depth, MLD)的时空分布特征。结果表明:南大洋混合层存在明显的季节变化,冬春两季MLD在副南极锋面北侧达到最高值并呈带状分布,夏秋两季由于海表加热导致混合层变浅,季节变化幅度达到400m以上;在年际尺度上,MLD受南半球环状模(Southern HemisphereAnnularMode,SAM)调制,呈现纬向不对称空间分布特征,这与前人结果一致;本文指出在所研究时段,南大洋混合层在90°E以东,180°以西有加深趋势,而在60°W以西,180°以东有变浅趋势,显示出偶极子分布特征,并且这种趋势特征主要是风场的作用。 相似文献
9.
温度、盐度和压力是海洋重要的基本物理特性参数。温盐深测量仪(Conductivity Temperature Depth,CTD)是海水温盐剖面观测的关键仪器,在海洋经济开发、海洋观测、海洋国防建设方面有着极为重要的意义。本文介绍了几种典型的温盐深测量设备及移动观测平台,重点论述了CTD在Argo浮标、水下滑翔机等海洋移动观测平台上的应用现状,分析了水下滑翔机搭载的CTD在热滞效应、湍流等因素影响下产生的测量误差。最后探讨了以水下滑翔机为代表的海洋移动观测平台搭载CTD测量技术的发展趋势及应用前景。 相似文献
10.
北太平洋副热带模态水形成区混合层热动力过程诊断分析 总被引：2，自引：0，他引：2
利用NCEP海洋数据和COADS海气通量资料,通过诊断分析,揭示了海表热力强迫、垂直夹卷、埃克曼平流和地转平流效应在北太平洋副热带模态水形成过程中的贡献。研究表明,在北太平洋副热带3个模态水形成海域冬季混合层降温过程中,海表热力强迫和垂直夹卷效应是主导因素,二者的相对贡献分别约为67%和19%(西部模态水)、53%和21%(中部模态水)、65%和30%(东部模态水);并且在东部模态水形成海域,埃克曼平流和地转平流皆是暖平流效应,而在西部和中部模态水形成海域,仅有地转平流是暖平流效应。进一步的分析表明,海洋平流(地转平流、埃克曼平流)对北太平洋副热带模态水形成海域秋、冬季混合层温度的年际、年代际异常有显著影响,在西部模态水形成海域,海表热力强迫(62%)和地转平流(32%)是导致混合层温度年际、年代际变化的主要因子;在中部模态水形成海域,混合层温度的年际、年代际变化是埃克曼平流(32%)、地转平流(30%)和海表热力强迫(25%)共同作用的结果;相对而言,东部模态水形成海域混合层温度的年际、年代际异常主要受海表热力强迫(67%)控制。 相似文献
11.
基于水下滑翔机观测资料,对南海北部一个反气旋涡旋的温度细结构进行了特征分析.温度细结构强度由温度的脉动值确定,并随着尺度的增加呈指数衰减.在垂直方向上,细结构强度随着深度的加深而减弱,细结构特征在海洋表层(0～100m)和表层以下(＞100 m)存在显著区别.表层内,垂向混合和水平混合对细结构强度均有贡献,细结构强度大... 相似文献
12.
水下滑翔机其通过集成生物、化学、物理传感器可以测量如温度、盐度、溶解氧等多种海洋基础水文要素,其利用卫星定位系统获得实际出水速度和理论出水模型获得理论出水速度之差可以计算深度平均流,。本文利用海翼水下滑翔机获得温盐场及卫星定位数据评估深度平均流,结果显示利用温盐场获得深度平均地转流与水下滑翔机获得深度平均流相关系数0.95,表明其流场的一致性,同时根据船载观测ADCP误差分析法估算深度平均流误差约为0.036 m/s。借助深度平均流可以估算绝对地转流,包括正压地转流和斜压地转流。在零动力面的假设下,我们选取了海翼号水下滑翔机在南海的一组实验对流量误差进行了评估。该实验为2019年1月3日-2月16日海翼号水下滑翔机自南向北穿越西沙群岛附近一个中尺度涡观测。观测结果表明,该中尺度涡为冷涡流核,在涡心以南,绝对地转流为东向流,最大流速约为0.48 m/s;涡心以北,绝对地转流为西向流,最大流速约为0.47 m/s,稍弱于南侧。受不均匀时空观测计划影响,本文未对流量做出估计。 相似文献
13.
The Kuroshio Extension System: Its Large-Scale Variability and Role in the Midlatitude Ocean-Atmosphere Interaction 总被引：7，自引：0，他引：7
Bo Qiu 《Journal of Oceanography》2002,58(1):57-75
The Kuroshio Extension and its recirculation gyre form an interconnected dynamic system. The system is located at a crossroads
where the meso-scale and large-scale oceanic variability are highest, and where the ocean-atmosphere interaction is most active
in the Pacific Ocean outside of the tropics. Following a brief review of the mean flow and meso-scale eddy variability, this
study describes in detail the large-scale structural change (an oscillation between an elongated and a contracted state) observed
in the Kuroshio Extension system. Causes for this structural change are explored next, and it is argued that the basin-wide
external wind forcing and the nonlinear dynamics associated with the inertial recirculation gyre are both important factors.
Data analysis results are reviewed and presented, emphasizing that the surface Kuroshio Extension is not simply a well-mixed layer passively responding to heat flux anomalies imposed by the atmosphere. It is argued that large-scale
changes in the Kuroshio Extension system influence the surface ocean heat balance and generate wintertime sea surface temperature
(SST) anomalies through both horizontal geostrophic heat advection and re-emergence to the surface mixed layer of sequestered mode water temperature anomalies.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
14.
利用TOGA—COARE计划的强化观测资料,对《实验3号》科学考察船第一和第二两个航次期间暖池区内感热、潜热和海面净热通量、动量通量和混合层深度、SST变化进行计算和初步分析。指出:上述各量都存在明显的季节内时间尺度变化。从对计算结果的对比分析得出:SST的变化与垂直混合、潜热输送和云对短波辐射的调节作用有比较密切的关系。可以认为,海洋SST季节内时间尺度的变化可能与大气的动力和热力强迫有直接的关系。 相似文献
15.
Interannual variability in the Mindanao Eddy and its impact on thermohaline structure pattern 总被引：2，自引：0，他引：2
The major feature,interannual variability and variation cause of the Mindanao Eddy and its impact on the thermohaline structure are analyzed based on the Argo profiling float data,the history observed data and the SODA data.The analysis results show that the Mindanao Eddy is a permanent cyclonic meso-scale eddy and spreads vertically from about 500 m depth upward do about 50 m depth.In addition to its strong seasonal variability,the Mindanao Eddy displays a remarkable interannual variability associated with ENSO.It strengthens and expands eastward during El Nin o while it weakens and retreats westward during La Nin a.The interannual variability in the Mindanao Eddy may be caused by the North Equatorial Counter Current,the North Equatorial Current,the Mindanao Current and the Indonesian Through Flow.The eddy variability can have a great influence on the thermohaline structure pattern in the local upper ocean.When the eddy is strong,the cold and low salinity water inside the eddy moves violently upward from deep layer,the thermocline depth greatly shoals,and the subsurface high salinity water largely decreases,with the upper mixed layer becoming thinner,and vice versa. 相似文献
16.
本研究基于中国科学院沈阳自动化研究所自主研发的水下滑翔机在热带东太平洋观测获取的连续剖面温盐数据,并通过与多套不同数据的比测,证实国产水下滑翔机观测的温盐数据准确可靠,未来可大范围应用于深海大洋。观测结果首次发现该海域北太平洋中央水（NPCW）（50~100 m）的60~80 m层分布着中间层低盐水,分析认为该低盐水来源于水团下方的加利福尼亚流系水（CCS）,中间层低盐水形成的动力机制主要受跃层附近的内波控制,并与内波强度密切相关,同时受上层（20~60 m）障碍层的影响,该中间层低盐水仅仅出现在60~80 m。本研究发现内波与障碍层能够通过影响动能与热能的传输进而促进水团新结构的形成,相关成果丰富了内波与障碍层对上层海洋响应的研究,具有重要的科学价值。 相似文献
17.
南海混合层深度的季节变化及年际变化特征 总被引：2，自引：0，他引：2
通过分析新的SODA(Simple Ocean Data Assimilation)资料,得到南海混合层时空场的分布特征,剖析了南海混合层深度的季节及年际变化特征。资料分析表明:南海混合层存在着显著的季节和年际变化,且两者的均方差分布存在一定的差异。在季节变化中,冬季混合层在南海北部及西北陆架区深,在南海南部及吕宋冷涡处浅;夏季混合层在南海西北部浅,东南深。南海这种混合层深度分布特征除了与热通量的季节变化有关外,在相当大的程度上与季风引起的Ekman输送及Ekman抽吸有关。混合层深度距平场EOF(Empirical Othorgnal Function)第一模和第二模时间变化的主信号均为周期的年际变化信号,其中第一模态约为3 a,第二模态则有1.8,2.4和4.3 a的3个显著周期。EOF第一模显示混合层深度在南海东南部年际变化幅度最大,且滞后Nino3指数7个月时相关性最好(相关系数为0.422 3);EOF第二模显示在南海南部和北部混合层深度呈反位相变化。 相似文献
18.
Underwater glider is an autonomous underwater vehicle that glides by controlling their buoyancy and attitude using internal actuators. By changing the vehicle's buoyancy intermittently, vertical motion can be achieved. Characteristics of glider motion include upward and downward movement in a saw tooth pattern, turning and gliding in a vertical spiral motion and gliding without using thrusters or propellers. This paper presents the modelling and identification on net buoyancy, depth and pitching angle of an underwater glider system. A ballast tank subsystem is considered appropriate for the identification process since it is the main parameter for the motion control. By selecting the ballast rate as the input, three aspects of the dynamics of a glider can be observed: buoyancy, depth of the glider and pitching angle. The MATLAB System Identification ToolboxTM is used to obtain a mathematical model of the glider ballast-buoyancy, ballast-depth and ballast-pitching angle conditioning system. The best three parametric estimation models are chosen, and the results of the comparison between simulated and estimated outputs are presented. The information obtained from the modelling and identification approaches are used for USM's Underwater Glider Prototype controller design. The information observed during this procedure are utilised for optimisation, stability, reliability and robustness analysis of the underwater glider. 相似文献
19.
In order to confirm the results of the authors’ previous work, which found that the existence of disturbances smaller than
meso-scale eddies is important in large-scale mixing process between the Oyashio and Kuroshio waters in the intermediate layer,
the results of an eddy-resolving model experiment are analyzed and compared with those of an eddy-permitting model. The intermediate
salinity minimum given in the initial condition weakens as integration advances in the eddy-permitting model, while it recovers
rapidly and is maintained thereafter in the eddy-resolving model, initialized from the unrealistic salinity distribution of
the former. Filament-like fine structures in temperature and salinity develop actively in the latter, which are much smaller
in horizontal width than meso-scale eddies, suggesting the importance of such disturbances in the large-scale mixing. The
mixing ratio of the Oyashio water defined by the original Oyashio and Kuroshio waters shows that its value is generally higher
in the intermediate lower sub-layer than in the intermediate upper sub-layer in the Mixed Water Region, and the salinity minimum
exists between layers with low and high values of the mixing ratio with its strong vertical gradient. The eddy transports
of the Oyashio and Kuroshio waters in an isopycnal layer are divided into four components, usual isopycnal mixing of temperature
and salinity being dominant, followed by the component associated with the thickness flux. The southward eddy transport of
the Oyashio water and the northward eddy transport of the Kuroshio water are not symmetric to each other because the thickness-flux-associated
components are in the same direction (southward). 相似文献
20.
Case study on the three-dimensional structure of meso-scale eddy in the South China Sea based on a high-resolution model 总被引：1，自引：1，他引：0
Meso-scale eddies are important features in the South China Sea(SCS). The eddies with diameters of 50–200 km can greatly impact the transport of heat, momentum, and tracers. A high-resolution wave-tide-circulation coupled model was developed to simulate the meso-scale eddy in the SCS in this study. The aim of this study is to examine the model ability to simulate the meso-scale eddy in the SCS without data assimilations The simulated Sea Surface Height(SSH) anomalies agree with the observed the AVISO SSH anomalies well. The simulated subsurface temperature profiles agree with the CTD observation data from the ROSE(Responses of Marine Hazards to climate change in the Western Pacific) project. The simulated upper-ocean currents also agree with the main circulation based on observations. A warm eddy is identified in winter in the northern SCS. The position and domain of the simulated eddy are confirmed by the observed sea surface height data from the AVISO. The result shows that the model has the ability to simulate the meso-scale eddy in the SCS without data assimilation.The three-dimensional structure of the meso-scale eddy in the SCS is analyzed using the model result. It is found that the eddy center is tilted vertically, which agrees with the observation. It is also found that the velocity center of the eddy does not coincide with the temperature center of the eddy. The result shows that the model has the ability to simulate the meso-scale eddy in the SCS without data assimilations. Further study on the forming mechanism and the three-dimensional structure of the meso-scale eddies will be carried out using the model result and cruise observation data in the near future. 相似文献