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101.
本文在对位于黄海南部陆架上的朝连岛站30年水温资料进行分析时发现,该站的表层水温有周期大于20个月的低频振动,其中以准两年周期和6年周期最显著。陆架水温的这种低频振动是对东亚季风异常的响应。这种低频振动在冬季与渤海冰情的变化同步;在夏季与黄海底层冷水团的强弱相关。同时,这种低频振动在对马暖流上也有一定的反映。 相似文献
102.
We study the problem of determination of the sound field of a point harmonic source in the coastal zone and the influence of a cylindrical body floating above the source on the sound field formed in the marine medium. A numerical-analytic method is proposed for the determination of the velocity potential. According to this method, the unknown coefficients in the general solution of the problem are determined from the corresponding infinite system of linear algebraic equations by the method of reduction. We present results of numerical calculations for a special case of a waveguide whose parameters are typical of the coastal part of the sea and perform the comparative analysis of the data obtained as a result of variation of the indicated parameters. 相似文献
103.
In the food clods of the mass species of macrobenthos of the Gryaznaya Inlet, nonstructured matter plays a great role. We identify this matter as derivates from plant tissues, which are the products of their external metabolism and degradation, with associated microorganisms. This way, the near-shore community considered is supported by a detrital trophic web. This feature distinguishes it from the similar community of the near-Atlantic waters that is based on a pasture web, at least as far as the bivalve mass species are concerned. The groups of the near-shore species of Gryaznaya Inlet separated by a cluster analysis are identified as consortia, combined by the biogeochemical conditions (edifice factor), which can hardly be analyzed at present. 相似文献
104.
The basic properties of the dynamic model of a turbulent jet formed by a deep-water sewage discharge into the stratified environment of coastal regions are considered. The model developed was used to estimate the parameters of a floating-up jet of deep wastewater discharge from Sand Island into the basin of Mamala Bay (Hawaii) depending on the season and discharge operation mode. The estimates of the float-up depths of the jet and the initial dilution of the jet were estimated on the basis of model calculations using experimental data on the vertical profiles of the water temperature and salinity under the actual conditions of stratification in the study region. It is shown that the further propagation of the wastewater jet depends on tidal events and internal waves generated by tides. The appearance of turbulent jets at the sea surface was recorded. The model estimates of the parameters of the wastewater discharge were compared with the results of experimental measurements. Good agreement was found, which indicates that the physical mechanisms of the propagation of turbulent jets in a stratified medium are adequately described by the model. 相似文献
105.
为了评价海洋水色卫星遥感器特性参数的优劣,确定仪器的计量特性及其使用价值,准确的理解和科学的定义仪器的特性参数是非常重要的。作者曾有幸参加了海洋水色卫星的立项论证工作,本文就作者的一些工作体会,对海洋水色卫星遥感器的特性参数作初步探讨。 相似文献
106.
107.
东太平洋柱状沉积物的古气候和古环境记录 总被引:1,自引:2,他引:1
太平洋深海盆地的远洋沉积物在物质组成和来源上远较大陆边缘简单.由于远离大陆,又有海沟与周边大陆分隔,太平洋深海沉积物中通常不包含由河流水系搬运而来的悬浮物,因此从深海沉积物中提取古气候、古环境信息可以避免诸多地质因素相互叠加和干扰[1].深海远洋沉积物中的主要组分是风成陆源碎屑(包括火山碎屑)和来自上层海水的生源组分(降落到洋底的生物壳体)以及由海解作用形成的自生矿物[2],其中陆源碎屑的相对含量、粒度及矿物成分可以反映大气环流的强度及物源区的气候环境[1],生源组分的组成、相对含量和丰度以及种属含量变化则与表层海水的生产力和溶解作用有关. 相似文献
108.
Spatial and temporal variability of heat content above the thermocline in the tropical Pacific Ocean 总被引:1,自引:0,他引:1
Abstract-Heat content of the upper layer above the 20℃ isotherm in the tropical Pacific Ocean isestimated by using the sea temperature data set with a resolution 2°latitude×5°longitude (1980~1993)for the water depths (every 10 m) from 0 m to 400 m, and its temporal and spatial variabilities are an-alyzed. (1) The temporal variability indicates that the total heat in the upper layer of the equatorial Pa-cific Ocean is charcterized by the interannual variability. The time series of the equatorial heat anomaly5 months lead that of the El Nino index at the best positive lag correlation between the two, and theformer 13 months lag behind the latter at their best negative lag correlation. Therefore the equatorialheat content can be used as a better predictor than the El Nino index for a warm or cold event. In addi-tion, it is also found that less heat anomaly in the equator corresponds to the stronger warm events inthe period (1980~1993) and much more heat was accumulated in the 4 years including 1992/1 相似文献
109.
1 998年 5— 9月 ,通过培养实验 ,研究了海洋底栖性有毒甲藻Cooliamonotis人工培养生长所需的理化条件。结果表明 ,培养水体深度较小而水平横截面积较大有利于获得较高产量。温度 1 6— 3 2℃、盐度 2 4— 3 8、K培养液浓度系列 1 /8K— 2K、培养液pH为 6 .5— 9.5都可存活 ,最大指数期平均生长率为 0 .6 9division·d- 1 ,获得的最大细胞密度为 6× 1 0 4 cells·ml- 1 ,是一种适应性较强的微藻。保种条件以温度 2 4℃、盐度 3 4、培养液浓度K ,pH为8.0为佳。 相似文献
110.
O. O. Trusenkova S. V. Stanichnyi Yu. B. Ratner 《Izvestiya Atmospheric and Oceanic Physics》2007,43(5):634-648
The expansion of wind fields observed at fixed times (four times daily) in complex empirical orthogonal functions is performed for the Japan Sea area (34°–53° N, 127°–143° E). The wind fields are taken from the 1998–2004 NCEP/NCAR Reanalysis data with better spatial resolution (1° × 1°) than the standard product, which are publicly available on the Internet. Major modes of wind variability in the Japan Sea area are identified. The modes determine a general direction of air-mass transport throughout a year, zonal and meridional modulation, and a cyclonic and an anticyclonic eddy component. Objective classification of wind fields with respect to the prevailing flow direction is performed, and wind stress and wind-curl patterns are obtained for major events in the cold and warm periods of the year. The pattern obtained can be used in hydrodynamic numerical models of the general circulation of the Japan Sea. 相似文献