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131.
132.
133.
Predictability of Interannual Variability in the Kuroshio Transport South of Japan Based on Wind Stress Data over the North Pacific 总被引:1,自引:3,他引:1
It is expected that a roughly two-year forecast of the Kuroshio transport variation can be made from a past record of wind
stress data over the ocean, since it takes nearly ten years for the first-mode baroclinic Rossby wave to traverse the entire
basin in the midlatitude North Pacific (∼30°N). We therefore investigated the predictability using an ocean general circulation
model driven by the wind stress data from the National Centers for Environmental Prediction/National Center for Atmospheric
Research (NCEP/NCAR) reanalysis. Referring to a hindcast experiment as the control run, we carried out fifteen forecast experiments,
the initial conditions of which are taken from the hindcast experiment at intervals of two years during the period from the
end of 1969 to the end of 1997. Each of the forecast experiments is driven only by wind stress in the year preceding each
experiment. The forecasted Kuroshio transport anomaly south of Japan agrees better with the hindcasted one during the first
two years of the forecast in most cases. In some cases, however, significant disagreements occur, most of which are likely
due to larger unpredictable variations caused by wind stress anomalies near Japan. At the end of forecast year 2, the anomaly
correlation coefficient is about 0.7, and rms of the forecast error is smaller than rms of the hindcasted anomaly. These results
indicate that the prediction of the interannual variability in the Kuroshio transport could be made two years in advance at
a statistically significant level.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
134.
揭示Rankine涡风场模式和Jelesnianski风场模式之间的联系,并设计了一种台风风场分布模式,它的风速分布曲线落在Jelesnianski和Rankine涡两个风场模式的风速分布曲线之间,具有一个既优于Jelesnianski又优于Rankine涡的风速衰减速率,因此它同时克服了Rankine涡模式计算风速偏小和Jelesnianski模式计算风速偏大的缺点,以一种比较合理的变化趋势向远方衰减,成为一个比较切合实际的台风风场分布模式。同时,文中提出的移行台风风场计算方法对宫崎正卫、上野武夫和Jelesnianski模式都有一定的改进。 相似文献
135.
136.
Fayun Liang Mingyi Zhao Chengrui Qin Yajie Jia Zhongwei Wang Guiping Yue 《Marine Georesources & Geotechnology》2020,38(1):114-121
AbstractThe construction of a 100-km road network is planned on a land reclamation area in the Oujiang Estuary in China. The embankment had a height of 4 m and a base width of 60 m. The reclamation area is newly filled by a 3-m dredger fill on a 48-m thick layer of marine clay. Estimation of the settlement of the future road network is difficult. To guide the construction of the road network, a 1/100-scale centrifuge model test was performed with a marine clay sample from the construction site to simulate the layered settlements and evaluate the drainage effect of prefabricated vertical drains in the dredger fill in the following 10 years. The results of the centrifuge modeling test are verified by 10-month in situ monitoring, which shows agreement between the centrifuge modeling test results and the in situ results. The test results indicate that additional time is needed to reinforce the newly added dredger fill by the surcharge preloading method to uplift the elevation of the reclamation area with dredger fill. 相似文献
137.
海洋光合有效辐射分布的计算模式 总被引:7,自引:1,他引:7
针对一类海水,采用美国标准大气模型和一类水体海洋生物-光学特性的半分析方法,建立了海洋光合有效辐射计算模式。模式比较全面地考虑了大气、海-气界面和水体的光辐射传输过程,能较好地用于分析叶绿素浓度以及光辐射场的角分布对光俣有效辐射分布的影响。对模拟结果的分析以及与实测结果的比较表明,该模式能较好地应用于计算衰减系数、光谱辐照度随深度的分布、光合有效辐射随深度的分布和真光层深度,在海洋生态系统的光动力学研究和水色遥感方面有效好的应用前景。 相似文献
138.
本文提出了一种地震折射液的虚拟射线理论,根据该理论,只要已知地表层的速度,即可直接由折射波信息提取地震参数,从而可实现折射界面的反演。 文中通过实际介质模型的计算机实验结果,验证了该理论的正确性。 相似文献
139.
The expansion of offshore activities and the increasing need to meet international and national commitments to biodiversity conservation have led to an enhanced interest in marine spatial planning (MSP) as a tool for sea use management. Several European countries, on their own initiative or driven by European legislation and policy, have taken global leadership in implementing MSP. This article will discuss the Belgian experiences with MSP. It will give a short historical overview based on legal developments and review the implementation process of a ‘Master Plan’ as a spatial management policy for the Belgian Part of the North Sea. Additionally, this article will reflect on the research that has been done in Belgium to apply a land-use planning approach to the marine environment. The MSP process in Belgium shows that a spatial approach to sea use management is possible despite the lack of a legal zoning framework. However, it concludes that a legal basis for MSP, in addition to the current permit system, would provide a more strategic and integrated framework for ecosystem-based, sea use management. 相似文献
140.
研究了2003年10月采于珠江口5个站位的沉积物剖面酸挥发性硫化物(AVS)和同时提取的重金属(SEM:Pb,Zn,Cu,Cd,Ni)。其中,站位1、2位于中滩,其沉积物的AVS含量变化范围较小,为0.25—4.06μmol.g-1;站位3、4位于西滩,其沉积物的AVS含量变化范围较大,为0—26.09μmol.g-1。中滩和西滩沉积物的AVS含量均随深度增加。西滩表层沉积物的AVS含量接近于零,这可能与该水域较强的底层流和沉积物的再悬浮作用有关。站位5位于珠江口外侧,其表层沉积物的AVS含量相对较高,且垂向变化较小,可能是还原性沉积物间歇性再悬浮后重新沉积的结果。站位1、2和5沉积物中同时提取的重金属含量大体在0.95±0.2μmol.g-1范围内,随深度增加略呈下降趋势;而西滩沉积物重金属含量相对较高,为1.43—2.42μmol.g-1,且在一定深度范围内随深度增加呈明显下降的趋势,表明珠江口西滩沉积物中的重金属污染有加重的趋势。对AVS/SEM摩尔比值和单个金属的毒性效应研究显示,珠江口内尤其是西滩的表层沉积物存在重金属污染,对其中生活的底栖生物具有潜在的毒性效应。 相似文献