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1.
The NW Pacific Ocean is not onIy the only transportation way between America andAsia, but also the source influencing on inIand climate and marine variability of adjacentseas in China. Based on ship observation data during l950 - l995 in the NW Pacific,with data from several hundreds to 30 thousand in every 5"x5" grid network, throughanalyzing the monthly mean directions of prevailing wind, wave and swelI, wind speed,pressure, wave height and frequencies of gaIe of 6 and 8 sca1e, high sea…  相似文献   

2.
太平洋内部副热带-热带经向翻转环流(subtropical-tropical cell,STC)是连接热带和副热带的海洋通道.由于以往海洋观测资料的匮乏,前人多利用海洋模式数据进行研究,且仅限于沿单一纬度上的STC的分析,较少涉及沿不同纬度的STC的季节变异规律.利用地转海洋学实时观测阵(array for real-...  相似文献   

3.
基于中国第29次南极科学考察期间获取的GPS探空观测数据,分析了东南印度洋和西南太平洋经向断面大气垂直结构的基本特征、季节变化和纬向差异。不同断面的大气垂向结构差异显著,但也具有共同特征,4000 m以下低空的气温和湿度明显高于高空,而低空风速明显小于高空风速,8000 m以上高空各个观测要素的垂直变化较小,整个断面主要以西风为主,整个垂直剖面湿度异常偏高(偏低)的区域通常对应上升(下沉)气流。给出了3个观测断面的大气锋面位置和类型,P1断面的大气锋面在47°~50°S,P2和P3断面的大气锋面在52°~58°S,P1和P2的锋面属于暖锋,P3的锋面由于气旋的影响分类不明显。东南印度洋大气剖面结构具有明显的季节变化,秋季和春季相比,秋季具有风速小,气温高特征,大气锋面更加偏南。东南印度洋和西南太平洋断面的大气剖面结构差异明显,二者相比,东南印度洋具有风速大、气温高及相对湿度小的特征,但大气锋面位置相同。  相似文献   

4.
1957~2002年南海—北印度洋海浪场波候特征分析   总被引:2,自引:0,他引:2  
郑崇伟  李训强  潘静 《台湾海峡》2012,31(3):317-323
利用ERA-40海表10 m风场驱动第三代海浪数值模式WAVEWATCH-Ⅲ,得到南海—北印度洋1957年9月至2002年8月的海浪场,并分析其波候(风候)特征.研究发现如下主要特征:(1)该海域的波高波向、风速风向受季风影响显著;(2)北印度洋大部分海域的海表风速呈显著性逐年线性递增趋势,大约0.01~0.02 m/(s·a),南海线性递增的区域则较少,有效波高呈显著性逐年线性递增的区域主要集中在低纬度中东印度洋(约0.003~0.006 m/a)、索马里附近海域(大约0.002~0.005 m/a)、南海大部分海域(约0.002~0.004 m/a),线性递减的区域主要集中在孟加拉湾海域(约-0.002 m/a);(3)Nino3指数与南海—北印度洋的海表风场、浪场存在密切的关系;(4)南海—北印度洋的海表风速与有效波高存在5.2a左右的共同周期,南海的海表风速、有效波高还存在2.0a左右的共同周期,北印度洋的海表风速、有效波高还存在26.0a的长周期震荡.  相似文献   

5.
热带印度洋上层水温的年循环特征   总被引:1,自引:0,他引:1  
通过分析多年气候月平均的Levitus水温资料,结合多年气候月平均海表面风场资料以及观测的热带印度洋上层海流的分布状况,探讨热带印度洋上层水温的时空分布特征,剖析了热带印度洋混合层深度及印度洋暖水的季节变化规律。分析表明:热带印度洋的海表面温度低值区始终位于大洋的南部,而高值区呈现明显的季节变化,冬季位于赤道附近,在夏季则处于大洋的东北部;在热带印度洋的中西部、赤道偏南海域的次表层终年存在一冷心结构;热带印度洋表面风场的季节变化是影响该海域混合层深度季节性变化的主要因素;印度洋暖水在冬、春季范围较大,与西太平洋暖池相连,而在夏、秋季范围较小,并与西太平洋暖池分开。  相似文献   

6.
利用1979—2021 年的 ERA5 再分析资料,采用经验正交函数分解法、Mann-Kendall 趋势检验法等统计方法,对“21 世纪海上丝绸之路”相关海区的海表风场与风能密度的空间分布特征、季节变化特征以及长期变化趋势进行分析。结果表明:(1)研究海域风能密度在不同季节表现出很大的空间差异,夏季的阿拉伯海和孟加拉湾,冬季的中国南海,以及全年的热带南印度洋风能资源都极为丰富。(2)研究时段内,中国南海北部及附近海域、阿拉伯海西部、孟加拉湾西部以及热带西北印度洋风能密度等级整体较高。(3)研究海域的风能密度以年变化特征为主,其中中国南海风能密度的季节变幅最大且在春、秋两季表现出明显的转换特征。(4)在研究海区中,结合水深条件与风能密度时空变化特征的评估结果,可以重点关注台湾海峡、吕宋海峡、中南半岛东南沿海、阿拉伯海西部近岸海域及热带西北印度洋近岸大陆架海域风能资源的开发利用,加强其他海域风能资源的储备。此研究可为“21 世纪海上丝绸之路”风能资源的中长期开发规划提供依据。  相似文献   

7.
南印度洋SST与南亚季风环流年代际变化的研究   总被引:2,自引:0,他引:2  
利用美国NCEP全球大气再分析资料和JONES全球海表面温度异常(SSTA)资料,分析了南印度洋SSTA和南亚季风环流年代际变化的特征。研究发现,无论是南印度洋副热带海水辐合区的SST还是赤道以北非洲西海岸附近上升运动海区的SST的长期变化趋势,除了准3-5年的变化以外,还存在着明显的年代际的变化。对于全球最显著南亚季风环流的分析表明,南亚季风环流也存在明显的年代际时间尺度的变化。与南太平洋SST的年代际变化相比,南印度洋SST的变化周期要相对短一些。通过分析南半球冷空气年代际活动的特征发现,冷空气与南印度洋SST年代际时间尺度的变化具有密切的联系。  相似文献   

8.
赤道印度洋海温偶极子的气候影响及数值模拟研究   总被引:5,自引:0,他引:5  
在分析研究印度洋海温变化的基本特征,尤其是在分析赤道印度洋海温偶极子及其影响的基础上,利用IAP9L大气环流模式模拟研究了赤道印度洋海温偶极子异常对亚洲季风区气候变化的影响.其结果表明,印度洋、亚洲南部和东部地区的流场和降水都对印度洋海温异常的强迫作用比较敏感.正位相印度洋偶极子的作用使得赤道东印度洋-印度次大陆南部-阿拉伯海一带出现距平东风,孟加拉湾-中南半岛出现异常反气旋性环流,从而对减少印度南部和中南半岛南部、印度尼西亚地区的夏季降水,以及增加中国南部和东非的夏季降水有十分重要的作用.与此相反,负位相印度洋偶极子的作用将使赤道东印度洋附近出现西风异常,孟加拉湾-中南半岛存在异常气旋性环流,从而使印度次大陆和中南半岛南部、印度尼西亚地区的降水增加,使中国西部和孟加拉湾的降水减少.数值模拟结果与资料分析相互映证,切实地揭示了印度洋海温偶极子对亚洲季风区的气候变化有重要影响.  相似文献   

9.
The dynamic importance of the Southern Indian Ocean (SIO) lies in the fact that it connects the three major world oceans: the Pacific, Atlantic, and Indian Oceans. Modeling study has been used to understand the circulation pattern of this very important region. Simulation of SIO (10°N–60°S and 30°E–120°E) is performed with z-coordinate Ocean General Circulation Model (OGCM) viz; MOM3.0 and the results have been compared with observed ship drift data. It is found that except near coastal boundaries and in equatorial region, the simulated current reproduce most well known current pattern such as Antarctic Circumpolar Current (ACC), South Equatorial Current (SEC) etc. and bears a resemblance to that of the observed data; however the magnitude of the surface current is weaker in model than the observed data, which may be due to deficiency in the forcing field and boundary condition and problem with observed data. The annual mean wind stress curl computed over the oceanic domain reveals about ACC and its similar importance. The way in which the ocean responds to the windstress and vertically integrated transport using model output is fascinating and rather good.  相似文献   

10.
Ocean Model Simulation of Southern Indian Ocean Surface Currents   总被引:1,自引:0,他引:1  
The dynamic importance of the Southern Indian Ocean (SIO) lies in the fact that it connects the three major world oceans: the Pacific, Atlantic, and Indian Oceans. Modeling study has been used to understand the circulation pattern of this very important region. Simulation of SIO (10°N-60°S and 30°E-120°E) is performed with z-coordinate Ocean General Circulation Model (OGCM) viz; MOM3.0 and the results have been compared with observed ship drift data. It is found that except near coastal boundaries and in equatorial region, the simulated current reproduce most well known current pattern such as Antarctic Circumpolar Current (ACC), South Equatorial Current (SEC) etc. and bears a resemblance to that of the observed data; however the magnitude of the surface current is weaker in model than the observed data, which may be due to deficiency in the forcing field and boundary condition and problem with observed data. The annual mean wind stress curl computed over the oceanic domain reveals about ACC and its similar importance. The way in which the ocean responds to the windstress and vertically integrated transport using model output is fascinating and rather good.  相似文献   

11.
The significant wave height and wind speed derived for the period 1993–2010 from altimeter data sets over the Arabian Sea, Bay of Bengal, and the Indian Ocean categorized as six zones has been analyzed. The average variation of both significant wave height and wind speed is found to be almost stable for the period of study. The study reveals that the average wind speed increases by about 6cm/sec/year during monsoon and post monsoon in the southern Indian Ocean. The distribution of wind and waves was studied in the context of seasonal variations. In addition, the average inter-annual and intra-annual variations along with the statistical parameters such as standard deviation, and root mean square wave height for the six zones are also reported in this paper.  相似文献   

12.
南海的季节与年平均风应力   总被引:2,自引:0,他引:2  
本文根据1982年中国近海及西北太平洋气候图集的风玫瑰资料计算南海各季与年平均风应力场。初步揭示了南海风应力的分布特征与其季节变化规律。  相似文献   

13.

The Indonesian throughflow (ITF) transports a significant amount of warm freshwater from the Pacific to the Indian Ocean, making it critical to the global climate system. This study examines decadal ITF variations using ocean reanalysis data as well as climate model simulations from the Coupled Model Inter-comparison Project Phase 5 (CMIP5). While the observed annual cycle of ITF transport is known to be correlated with the annual cycle of sea surface height (SSH) difference between the Pacific and Indian Oceans, ocean reanalysis data (1959–2015) show that the Pacific Ocean SSH variability controls more than 85% of ITF variation on decadal timescales. In contrast, the Indian Ocean SSH variability contributes less than 15%. While those observed contributions are mostly reproduced in the CMIP5 historical simulations, an analysis of future climate projections shows a 25–30% increase in the Indian Ocean SSH variability to decadal ITF variations and a corresponding decrease in the Pacific contribution. These projected changes in the Indian Ocean SSH variability are associated with a 23% increase in the amplitudes of negative zonal wind stress anomalies over the equatorial Indian Ocean, along with a 12º eastward shift in the center of action in these anomalies. This combined effect of the increased amplitude and eastward shift in the zonal wind stress increases the SSHA variance over the Indian Ocean, increasing its contribution to the ITF variation. The decadal ITF changes discussed in this study will be crucial in understanding the future global climate variability, strongly coupled to Indo-Pacific interactions.

  相似文献   

14.
利用剖面浮标的温盐观测资料和上层温度观测资料以及ECCO风应力数据研究了东南印度洋各主要海洋锋的位置、走向和风场的季节变化,并初步分析了亚热带锋(STF)和亚南极锋(SAF)的成锋机制.季节平均的夏季和冬季厄加勒斯锋(AF)分别可以延伸到80°E和82°E,AF在多数情况下可能与SAF和南亚热带锋(SSTF)汇合共同通过Kerguelen-Amsterdam Passage.在克尔盖伦海台以东海盆区,冬季SAF和PF的路径均比夏季偏南,在其他海域二者路径的季节差别不大.克尔盖伦海台以东的深海盆由北向南正负风应力旋度高值中心交替出现,且位置季节变化很小.85°~105°E之间零风应力旋度线位置冬季比夏季偏北.STF位于辐聚区,埃克曼抽吸导致的表层水辐聚可能是STF产生和维持的原因.SAF位置的季节南北摆动幅度小于风应力零旋度线的季节摆动幅度,夏季SAF位置略偏于风应力正旋度区,而冬季大多位于负旋度区,因此风应力旋度不是SAF形成的直接原因.  相似文献   

15.
基于2004—2018年Argo (Array for Real-Time Geostrophic Oceanography)浮标观测的温度、盐度数据, 利用经验正交函数(EOF)分析和小波分析等方法对北印度洋(40°—105°E, 5°S—25°N)障碍层时空分布特征进行分析。结果显示: 北印度洋的东部常年存在障碍层, 而西部障碍层出现的概率相对较低; 较厚的障碍层出现在阿拉伯海东南部(67°—75°E, 3°—12°N)、孟加拉湾(82°—93°E, 11°—20°N)和赤道东印度洋(81°—102°E, 4°S—3°N)。阿拉伯海东南部和孟加拉湾障碍层厚度以年变化为主, 且呈同位相变化, 均为冬季最大, 夏季最小。赤道东印度洋区域则主要呈现半年周期变化, 在夏季和冬季各出现一次峰值。进一步分析表明, 孟加拉湾和赤道东印度洋障碍层厚度主要受等温层深度变化影响, 混合层深度变化对障碍层厚度变化的影响相对较小; 阿拉伯海障碍层厚度同时受等温层深度变化和混合层深度变化影响, 其中等温层深度变化对其影响更大。  相似文献   

16.
Based on the latest oceanic surface drifter dataset from the global drifter program during 2000–2019, this study investigated the global variation of relative frequency shift(RFS), near-inertial energy(NIE) and inverse excess bandwidth(IEB) of near-inertial motions, and analyzed their relations with oceanic mesoscale dynamics, relative vorticity and strain. Compared with previous works, we have some new findings in this study:(1) the RFS was high with negative values in some regions in which we found a significant blue shift of the RFS in the equatorward of 30°N(S) and from 50°N to 60°N in the Pacific, and a red shift in the western boundary currents and their extension regions, the North Atlantic and the Antarctic Circumpolar Current regions;(2) more peak values of the NIE were found in global regions like the South Indian Ocean, the Luzon Strait and some areas of the South Ocean;(3) the global distribution of the IEB were characterized by clear zonal bands and affected by vorticity and wind field;(4)the RFS was elevated as the absolute value of the gradient of vorticity increased, the IEB did not depend on the gradient of vorticity, and the eddy kinetic energy(EKE) weakened with the decrease of the absolute value of RFS;(5) the NIE decreased with increasing absolute value of the relative vorticity and the gradient of vorticity, but it increased with increasing strain and EKE when EKE was larger than 0.003 2 m~2/s~2.  相似文献   

17.
The results obtained from an Ocean General Circulation Model (OGCM), the Modular Ocean Model 2.2, forced with the National Center for Environmental Prediction/National Center for Atmospheric Research reanalysis data, and observational data have been utilized to document the climatological seasonal cycle of the upper ocean response in the Tropical Indian Ocean. We address the various roles played by the net surface heat flux and the local and remote ocean dynamics for the seasonal variation of near-surface heat budget in the Tropical Indian Ocean. The investigation is based in seven selected boxes in the Arabian Sea, Bay of Bengal and the Equatorial Indian Ocean. The changes of basin-wide heat budget of ocean process in the Arabian Sea and the Western Equatorial Indian Ocean show an annual cycle, whereas those in the Bay of Bengal and the Eastern Equatorial Indian Ocean show a semi-annual cycle. The time tendency of heat budget in the Arabian Sea depends on both the net surface heat flux and ocean dynamics while on the other hand, that in the Bay of Bengal depends mainly on the net surface flux. However, it has been found that the changes of heat budget are very different between western and eastern regional sea areas in the Arabian Sea and the Bay of Bengal, respectively. This difference depends on seasonal variations of the different local wind forcing and the different ocean dynamics associated with ocean eddies and Kelvin and Rossby waves in each regional sea areas. We also discuss the comparison and the connection for the seasonal variation of near-surface heat budget among their regional sea areas. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

18.
The Chinese marine dynamic environment satellite HY-2B was launched in October 2018 and carries a Ku-band scatterometer. This paper focuses on the accuracies of HY-2B scatterometer wind data during the period from November 2018 to May 2021. The HY-2B wind data are validated against global moored buoys operated by the U.S. National Data Buoy Center and Tropical Atmosphere Ocean, numerical model data by the National Centers for Environmental Prediction, and the Advanced Scatterometer data issued b...  相似文献   

19.
印度洋上层海气相互作用对印度洋和太平洋气候系统有重要影响。目前针对印度洋气候态环流特征已有较为全面的研究,但针对印度洋环流的年际变化及其季节性差异的特征分析和具体作用机制,仍缺乏深入的研究。本文利用1979—2007年Simple Ocean Data Assimilation(SODA)再分析资料研究了赤道印度洋表层辐合辐散的年际变异及其季节依赖性。结果表明,以赤道为中心,印度洋上层异常海流,在经向上形成显著的辐合(辐散)现象,究其原因主要是赤道纬向风异常形成的Ekman流所导致。进一步分析表明,热带印度洋异常纬向风的成因与太平洋-印度洋的热力强迫过程作用有关,并且不同的热力强迫过程呈现出显著的季节差异性。此热力强迫过程,具体可分为3种类型:第一类是太平洋纬向海表热力差异的遥强迫作用,主要发生在冬末春初,热带太平洋的纬向热力差异通过调节Walker环流,在印度洋激发出一个异常的次级环流,对应的大气低层形成纬向风异常;第二类是东-西印度洋海表热力差异的局地强迫作用导致的局地环流,使赤道印度洋上空形成纬向风异常,此过程在春末夏初较为显著;第三类是太平洋-印度洋热力差协同作用的结果,使赤道印度洋盛行异常的纬向风,此过程在秋季起主导作用。  相似文献   

20.
Fronts and strong currents of the upper southeast Indian Ocean   总被引:3,自引:1,他引:2  
1 IntroductionBaroclinic component is the dominant part ofAntarcticCircum polarCurrent (ACC) (FandryandPillsbury,1979),and a baroclinictransportation asso-ciatedwithfrontsmakesupthem ajoritypartoftheto-talbaroclinictransportation oftheACC (Nowlin andCliff…  相似文献   

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