德雷克海峡上层海洋温度的年代际变化

采用经验模分解方法分析了德雷克海峡上层海洋温度的年代际变化特征.结果表明德雷克海峡上层海洋平均温度在1976-1986年以平均每年0.124 ℃的速度下降,而在1987-1998年以每年0.144 ℃的速度上升.与南方涛动指数的年代际时间尺度分量的相关性分析结果表明,热带太平洋海面气压场的变化对德雷克海峡上层海洋温度的年代际变化有一定影响.     

印尼马都拉海峡盆地上新统颗粒灰岩生物礁形成和演化模式

马都拉海峡盆地北部外陆架台地发育有E-W向一字排列的颗粒灰岩生物礁体。该生物礁是有孔虫（主要为抱球虫目）壳体经过各种沉积作用形成的堆积体,发育于早上新世挤压反转期盆地北部边缘区。由于生物礁生长发育所经历的特殊性,其岩石学特征等信息常常具有标志性的反映,因此礁体的剖面反射特征和地震属性相比于围岩会存在不小的差异。这些差异为人们利用地震解释和地震属性提取技术识别生物礁奠定了基础,如在地震剖面上,生物礁往往出现对称丘状外形反射、礁前斜坡前积反射、礁内部杂乱反射和不连续强反射的特征等等。以O-2井钻遇的存在抱球虫化石的马都拉海峡盆地上新统芒杜组沉积地层为研究对象,从地质背景入手,描述了盆地的新生代构造特征和发育各时期所对应的地层。通过进行层位标定和三维地震解释,结合地震属性提取技术,同时考虑到生物礁的发育形态与环境,最终获得了盆地抱球虫颗粒灰岩生物礁在空间上的分布。最后,本文结合盆地历史上的沉积构造活动,提出反转断裂带活动是研究区控制生物礁生长的重要因素,并据此总结了马都拉海峡盆地芒杜组台地边缘生物礁的发育模式。     

太平洋-印度洋贯穿流南海分支在卡里马塔海峡的十年观测回顾

除印度尼西亚贯穿流之外,南海贯穿流也是太平洋向印度洋输送海水的重要分支。尽管基于数值模拟等方法的研究早已指出,南海分支在太平洋-印度洋洋际交换中有重要作用,但是直到2007年之前,南海分支在卡里马塔海峡处的观测几乎是空白。本文回顾了自2007年起,通过中印尼合作项目"南海-印度尼西亚海水交换及对鱼类季节性洄游的影响（SITE）"在卡里马塔海峡开展的近十年观测,以及在此基础上进一步开展的"印度尼西亚贯穿流海域水交换、内波和混合观测及其生态效应（TIMIT）"观测项目,并对SITE和TIMIT观测取得的成果进行了总结。     

德雷克海峡绕极流和锋面的研究

利用我国第九次南极考察队获得的德雷克海峡地区水温资料,并结合国外锚碇浮标和测流资料,分析和研究了德雷克海峡绕极流和锋面的时间变化和空间变化.研究表明,德雷克海峡绕极流的流速共有3个强流区,就德雷克海峡上层海流的空间变化而言,以亚南极锋附近的海流最强,流向和流速也最稳定少变.德雷克海峡深层海流的空间分布特点与上层海流的空间分布特点不同,深层流速明显减弱,且稳定性差.德雷克海峡绕极流有着明显的时间变化,但是这种时间变化因地而异.极锋附近在冬春季节是稳定的深层北向流,它与南半球高纬度的冬、春季节的Ventilation过程有着密切的关系,德雷克海峡上层水温的空间分布具有明显的锋面分布特征.水温在德雷克海峡的高纬度区更加稳定少变,而极锋附近深层海水温度随时间的变化最大.     

基于调制不稳定性的吕宋海峡内孤立波生成机理探讨

The South China Sea (SCS) is a hot spot for oceanic internal solitary waves due to many factors, such as the complexity of the terrain environment. The internal solitary waves in the northern SCS mainl...     

北太平洋冬季大气年代际振荡及其相关的SST变化

20世纪60年代， Namias(1969)就发现北太平洋海平面气压(SLP)存在10a以上长周期的变化，这种变化与北美冬季气温异常密切相关。70年代以后，又有人(White et al.，1972； Trenberth，1990； Trenberth et al.，1994)对上述变化作了进一步的验证，并指出1976年以后北太平洋的SLP异常偏低，即阿留申低压异常偏强。以阿留申低压为主要活动中心的大气年代际振荡被称为北太平洋涛动(NPDO)，它与北大西洋涛动(NAO)一起构成年代际气候变动最重要的观测依据，北太平洋年代际振荡的机制也引起了人们的广泛兴趣。作为大气运动的缓变下垫面强迫之一的海表面温度(SST)，它的异常变化对年际气候的显著影响已被公认(Wallace et al.，1981，1998)，由此推断，其对年代际时间尺度气候变化的影响可能也不可忽视。众所周知，SST年际变化最显著区位于赤道中东太平洋(如Nino 3区)，而与北太平洋年代际振荡显著相关的SST变化(时间变化和空间分布)又如何呢?作者就这一问题，分析了北太平洋大气环流年代际振荡的时、空变化特征，并揭示了与之相关的SST变化的时间变化和空间分布。     

南印度洋副热带偶极子的年代际转变特征

为了增进对南印度洋副热带偶极子(Subtropical Indian Ocean Dipole,SIOD)年代际变化的认识,基于Hadley中心的海表面温度(sea surface temperature,SST)、美国国家环境预报中心的大气再分析数据集Ⅰ(NCEP-NCAR Reanalysis1,NCEP)的大气再分析数据和欧洲中期天气预报中心的海洋再分析数据(Ocean Reanalysis System 4,ORAS4)等,本文分析了1958～2020年SIOD年代际转变的特征和物理机制。结果显示,2000年之前,SIOD存在2～4 a和4～6 a两个年际主周期,但近20 a(2000～2020年)其年际变化周期以1.5～2.0 a为主。与此同时,SIOD的空间特征及其强度在1987年和2004年左右出现了两次显著的年代际转变:1958～1986年(P1)期间强度最大,1987～2003年(P2)期间最弱,2004～2020年(P3)期间居中;P1期间SIOD的最大正SST异常(sea surface temperature anomalies,SSTA)中心位于(46°～80...     

吕宋海峡Ekman输运和南海SST的相关性分析

在利用1950—2009年NCEP(National Center for Environmental Prediction)资料分析风场数据的基础上,计算吕宋海峡的Ekman输运,研究表明其存在显著的季节变化,除了夏季外,其它季节均为由太平洋向南海输运。分析吕宋海峡Ekman输运和南海海盆表征上层热力状况的海表面温度SST(Sea Surface Temperature)之间的关系发现:在年内时间尺度上,两者不存在显著的同期相关,Ekman输运对SST的影响开始于一个月之后,从北部向南扩展,第二个月最为明显,并扩展至整个海盆,第三个月开始衰减,第四个月影响消失,且相关性为正;在年际尺度上,吕宋海峡Ek-man输运的异常同南海SSTA(Sea Surface Temperature Abnormal)的第二模态存在显著的相关联系,并且吕宋海峡Ekman输运和南海SSTA的相关关系在北部为正,南部为负。吕宋海峡Ekman输运调制南海大尺度环流,通过暖、冷平流的作用影响南海SST的变化。     

黑潮对吕宋海峡全日内潮生成与传播影响的数值模拟研究

基于一套环流-潮汐耦合模型的模拟结果,本文探究并比较了2015—2016年的三种黑潮形态下,吕宋海峡全日内潮以及全日非相干内潮生成与传播的空间分布特征。结果表明,当黑潮以流套形态流经吕宋海峡时,全日内潮非相干性最强,具体表现为全日非相干内潮能量生成最大,全日内潮的传播速度变化率最大。由于传播速度的变化会改变全日内潮的位相,进而会影响全日内潮的非相干性,导致在吕宋海峡内全日内潮的非相干性最强。本研究结果对理解黑潮背景动力过程下吕宋海峡内潮的时空变化有重要意义。     

南印度洋SST在20世纪60年代的年代际转变及其相关气候变化过程

The change of sea surface temperature(SST) in the southern Indian Ocean(SIO) during the recent six decades has been analyzed based on oceanic reanalysis and model, as well as atmospheric data. The results show that a thermal regime shift in SIO during the 1960 s, which is not caught enough attentions, has been of equal magnitude to the linear warming since 1970. Empirical Orthogonal Function(EOF) analyses reveal that a thermal shift is combined with atmospheric changes such as the weakening of westerly during the period of 1960–1967. Inner dynamic connections can be defined that when the westerly winds turn weak, the anticyclonic wind circulation between westerly winds and the trade winds decreases, which further reduces the SST to a negative peak in this period. It is noted that the shifts in the 1960 s are also evident for Southern Hemisphere. For example, subtropical high and the entire westerly winds belt at high latitudes both change dramatically in the 1960 s. This large-scaled process maybe link to the change of southern annular mode(SAM).     

Distribution of macroalgae and seaweed in the Azov Sea,Kerch Strait,and Taman Bay

The analysis of the macroalgae distribution along the salinity gradient in the Azov Sea, the Kerch strait, and Taman Bay during the summer allowed finding two macroalgae complexes. The first complex (brackish) is formed by algae belonging to the Enteromorpha, Cladophora, Rhizoclonium, and Chaetomorpha genera in the Taganrog Gulf. The second complex (marine) with dominating algae belonging to the Enteromorpha, Chaetomorpha, Ceramium, and Polysiphonia inhabits the littoral part of the Azov Sea itself, the Kerch Strait, and Taman Bay. The saprobe analysis of the flora showed that the majority of macroalgae species inhabiting the Azov Sea are represented by meso- and polysaprobes and a small number of oligosaprobe species inhabit the Kerch Strait. The biggest species diversity of macroalgae was noted in the southwestern part of the sea; the value of Shannon’s index was 0.65 in the Taganrog Gulf, 1.04 in the Azov Sea, 1.38 in Taman Bay. The leading role in the littoral communities of Taganrog Gulf belongs to aquatic flowering plants with Potamogeton perfoliatus being dominant; as the salinity increases, the share of such species as P. pectinatus, Zostera marina, Z. noltii, Ruppia maritime, and Zannichellia major starts to increase.     

Analysis of the influence of water exchange through the Kerch Strait on the surge processes and currents in the Azov Sea

We present the results of numerical modeling of the influence of water exchange through the Kerch Strait on the stationary motions in the Azov Sea. We use a three-dimensional nonlinear numerical model to perform the analysis of extreme deviations of the sea level and the surface and deep-water currents depending on the direction and velocity of constant wind with and without regard for the water exchange through the strait. It is shown that the influence of water exchange with the Black Sea leads to the increase in the maximum deviations of the sea level and the velocities of stationary currents. Thus, in particular, it is shown that, for a wind velocity of 10 m/sec, the maximum values of the surge and current velocities in the presence of the strait are higher than in the absence of the strait by 36 and 42%, respectively. In this case, the highest current velocities are induced by the south wind.     

Numerical Analysis of the Effect of Active Wind Speed and Direction on Circulation of Sea of Azov Water with and without Allowance for the Water Exchange through the Kerch Strait

The effect of seawater movement through the Kerch Strait for extreme deviations in the level and speed of currents in the Sea of Azov caused by the action of climate wind fields has been studied using the Princeton ocean model (POM), a general three-dimensional nonlinear model of ocean circulation. Formation of the water flow through the strait is caused by the long-term action of the same type of atmospheric processes. The features of the water dynamics under conditions of changing intensity and active wind direction have been studied. Numerical experiments were carried out for two versions of model Sea of Azov basins: closed (without the Kerch Strait) and with a fluid boundary located in the Black Sea. The simulation results have shown that allowance for the strait leads to a significant change in the velocities of steady currents and level deviations at wind speeds greater than 5 m/s. The most significant effect on the parameters of steady-state movements is exerted by the speed of the wind that generates them; allowance for water exchange through the strait is less important. Analysis of the directions of atmospheric circulation has revealed that the response generated by the movement of water through the strait is most pronounced when a southeast wind is acting.     

Coupled modeling of currents and wind waves in the Kerch Strait

We present a numerical model of the dynamics of the Kerch Strait allowing one to perform the coordinated analysis of the fields of currents and wind waves. The model includes the spectral wave module and the hydrodynamic block of currents. The influence of waves on the currents is taken into account in the hydrodynamic block both via the surface and bottom tangential stresses and via the radiation stresses. In order to take into account the inverse influence of currents upon the waves, we use the fields of currents and sea level from the hydrodynamic block in the wave module. The specific features of the structure of currents and wind waves in the strait are studied for the typical wave situations. The results of the coupled and separate simulation are compared and the importance of taking into account the mechanisms of interaction between waves and currents in the analysis of the dynamic processes in the strait is demonstrated. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 5, pp. 3–20, September–October, 2007.     

Modeling of the breeze circulation of waters in the Kerch Strait

The problem of the numerical analysis of currents in the Kerch Strait is studied within the framework of a linear nonstationary two-dimensional model in the nondivergent approximation. We describe the actual situation when the motion is induced by a breeze against the background of the daily average northeast wind. The breeze is specified as acting in a narrow coastal strip and can be classified as a zonal wind. The variations of circulation near the Tuzla Island are studied in detail. It is shown that the contribution of the breeze circulation to the total circulation can be significant for the explanation of the processes running in the Kerch Strait. __________ Translated from Morskoi Gidrofizicheskii Zhurnal, No. 6, pp. 16–27, November–December, 2007.     

Modelling of the Sea of Azov ecosystem

The method of mathematical model self-organization is applied to handle observations of the hydrological, chemical and biological parameters of the Sea of Azov, conducted from 1926 through to 1985, in order to identify model equations of the latter's ecosystem. A set of 43 evolutionary equations have been employed to generate a picture of the ecosystem parameters' continuous variability and to identify relationships between them. Model calculations of the total catch of freshwater fishes, primary productivity, zoobenthos, phytoplankton, and other characteristics have demonstrated their being in good agreement with the observations conducted from 1950 to 1985. A prediction of the ecosystem parameters' evolution for the period from 1985 to 1995 has been made. Translated by Vladimir A. Puchkin.     

Numerical study of the Azov Sea level seiche oscillations

Seiche oscillations of the Azov Sea level are studied on the basis of the developed two-dimensional numerical hydrodynamic model grounded on the shallow water theory and recent data on the morphometric characteristics of the Sea of Azov. Frequency and spatial characteristics of the first five modes corresponding to seiche oscillations of the Azov Sea level are computed. It is shown that the frequency and spatial characteristics of the first five modes obtained for the Sea of Azov level changes correspond to seiche oscillations. The calculated parameters are compared with the field observations, which show their realistic character.