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131.
以美国国家环境预报中心(NCEP)再分析气象资料作为驱动风场条件,运用第三代海浪模式WAM的第四版本(WAMC4)在西北太平洋海域建立二级嵌套波浪模型,利用连云港、冷家沙现场观测波浪资料对模型进行了验证,检验了该模型在东中国海波浪研究中的适用性针对东中国海进行了连续60年(1950—2909)的波浪后报模拟,在此基础上开展了东中国海波浪时空分布特征研究.结果表明:四季的平均有效波高等值线与岸线形状基本保持一致,且由南向北逐渐递减;有效波高分布的季节差异显著,冬季浪高最大,其次为秋季,春季、夏季最小。通过对比分析平均波浪要素和5%累积频率波浪要素的定量关系发现,在渤海范围内,5%累积频率有效波高与平均有效波高之比约为2.75,黄海与东海大部该比值则分别约为2.50和2.35,而5%累积频率平均周期与平均周期的比值在整个东中国海范围内约为1.45。 相似文献
132.
白令海潮汐能通量和底边界能耗散 总被引:1,自引:0,他引:1
The spatial distribution of the energy flux, bottom boundary layer (BBL) energy dissipation, surface elevation amplitude and current magnitude of the major semidiurnal tidal constituents in the Bering Sea are examined in detail. These distributions are obtained from the results of a three-dimensional numerical simulation model (POM). Compared with observation data from seven stations, the root mean square errors of tidal height are 2.6 cm and 1.2 cm for M2 and N2 respectively, and those of phase-lag are 21.8° and 15.8° respectively. The majority of the tidal energy flux off the deep basin is along the shelf edge, although some of this flux crosses the shelf edge, especially in the southeast of the shelf break. The total M2 energy dissipation in the Bering Sea is 30.43 GW, which is about 10 times of that of N2 and S2. The semidiurnal tidal energy enters mainly to the Bering Sea by Samalga Pass, Amukta Pass and Seguam Pass, accounting more than 60% of the total energy entering the Being Sea from the Pacific. 相似文献
133.
通过对国外内河集装箱运输发展较好的主要国家和地区有关内河集装箱运输发展历程、航道及主要港口码头、船型及组织方式等基本情况的介绍,深入分析了国外内河集装箱运输发展的基本特点和主要趋势,总结了值得中国借鉴的国外内河集装箱运输发展经验。 相似文献
134.
Recent observations of hydrography, currents and volume transports in the straits of the East/Japan Sea are reviewed. It is newly found that bottom cold water in the Korea/Tsushima Strait originating from the northern region of the East/Japan Sea appears not only in summer and autumn but also in winter. Intensive observations in the Korea/Tsushima Strait revealed two distinct cores of northeastward currents in the upper layer of the western and eastern channels. Mean volume transport through the Korea/Tsushima Strait is calculated as 2.5 ± 0.5 Sv from four-year direct and indirect measurements. As continuous monitoring has started in the Tsugaru and Soya Straits, understanding of temporal variability of currents and volume transports through the straits is in progress. For the first time, simultaneous time series of volume transports are available in the Korea/Tsushima and Tsugaru Straits during the winter of 1999–2000. Ouflow through the Tsugaru Strait accounts for about 70% of inflow through the Korea/Tsushima Strait for this period. 相似文献
135.
游艇业——福建海洋经济的朝阳产业 总被引:3,自引:0,他引:3
充分利用福建船艇工业现有基础和区位优势发展游艇产业,将是福建海洋经济的新增长点,可带动海洋经济其他产业可持续发展能力的全面提升,缓解就业压力,优化产业结构,有利于形成特色鲜明、辐射面广、竞争力强的海洋产业聚集区和产业集群,为建设海峡西岸经济区提供强有力的产业支撑。 相似文献
136.
137.
Wave energy assessments in the Black Sea 总被引:1,自引:0,他引:1
Eugen Rusu 《Journal of Marine Science and Technology》2009,14(3):359-372
The present work aims to evaluate the wave energy resources in the Black Sea basin. The study is focused on the western part
of the sea, which is traditionally considered as being more energetic. In order to give a first perspective of the wave climate,
a medium-term wave analysis was carried out using in situ measured data. As a further step, a wave prediction system was implemented
for the Black Sea. This was based on the simulating waves near-shore model, which is used for both wave generation and near-shore
transformation. This methodology has the advantage that a single model covers the full scale of the modelling process. Various
tests were performed considering data measured at three different locations. Special attention was paid to the whitecapping
process, which is still widely considered to be the weak link in deep water wave modelling. Comparisons carried out against
measured data show that the wave prediction system generally provides reliable results, especially in terms of significant
wave heights and mean periods. By increasing the resolution in geographical space, the field distributions of wave energy
were analysed for both high and average wave conditions. The analysis and the wave prediction system developed are a prerequisite
for further investigations extended in time and with increased resolution in the near-shore direction. 相似文献
138.
Irene R. Schloss Christian Nozais Sbastien Mas Bon van Hardenberg Eddy Carmack Jean-ric Tremblay Sonia Brugel Serge Demers 《Journal of Marine Systems》2008,74(3-4):978
The distribution of picophytoplankton (0.2–2 µm) and nanophytoplankton (2–20 µm) in the Beaufort Sea–Mackenzie Shelf and Amundsen Gulf regions during autumn, 2002 is examined relative to their ambient water mass properties (salinity, temperature and nutrients: nitrate + nitrite, phosphate, and silicate) and to the ratio of variable to maximum fluorescence, Fv/Fm. Total phytoplankton and cell abundances (< 20 µm) were mainly correlated with salinity. Significant differences in picophytoplankton cell numbers were found among waters near the mouth of the Mackenzie River, ice melt waters and the underlying halocline water masses of Pacific origin. Picophytoplankton was the most abundant phytoplankton fraction during the autumnal season, probably reflecting low nitrate concentrations (surface waters average ~ 0.65 µM). The ratio Fv/Fm averaged 0.44, indicating that cells were still physiologically active, even though their concentrations were low (max Chl a = 0.9 mg m− 3). No significant differences in Fv/Fm were evident in the different water masses, indicating that rate limiting conditions for photosynthesis and growth were uniform across the whole system, which was in a pre-winter stage, and was probably already experiencing light limitation as a result of shortening day lengths. 相似文献
139.
Suspended sediment and erosion dynamics in Kugmallit Bay and Beaufort Sea during ice-free conditions 总被引:1,自引:0,他引:1
Tony R. Walker Jon Grant Peter Cranford D. Gwyn Lintern Paul Hill Peter Jarvis Jeffrey Barrell Christian Nozais 《Journal of Marine Systems》2008,74(3-4):794
The Mackenzie River is the largest river on the North American side of the Arctic and its huge freshwater and sediment load impacts the Canadian Beaufort Shelf. Huge quantities of sediment and associated organic carbon are transported in the Mackenzie plume into the interior of the Arctic Ocean mainly during the freshet (May to September). Changing climate scenarios portend increased coastal erosion and resuspension that lead to altered river-shelf-slope particle budgets. We measured sedimentation rates, suspended particulate matter (SPM), particle size and settling rates during ice-free conditions in Kugmallit Bay (3–5 m depth). Additionally, measurements of erosion rate, critical shear stress, particle size distribution and resuspension threshold of bottom sediments were examined at four regionally contrasting sites (33–523 m depth) on the Canadian Beaufort Shelf using a new method for assessing sediment erosion. Wind induced resuspension was evidenced by a strong relationship between SPM and wind speed in Kugmallit Bay. Deployment of sediment traps showed decreasing sedimentation rates at sites along an inshore–offshore transect ranging from 5400 to 3700 g m− 2 day− 1. Particle settling rates and size distributions measured using a Perspex settling chamber showed strong relationships between equivalent spherical diameter (ESD) and particle settling rates (r2 = 0.91). Mean settling rates were 0.72 cm s− 1 with corresponding ESD values of 0.9 mm. Undisturbed sediment cores were exposed to shear stress in an attempt to compare differences in sediment stability across the shelf during September to October 2003. Shear was generated by vertically oscillating a perforated disc at controlled frequencies corresponding to calibrated shear velocity using a piston grid erosion device. Critical (Type I) erosion thresholds (u) varied between 1.1 and 1.3 cm s− 1 with no obvious differences in location. Sediments at the deepest site Amundsen Gulf displayed the highest erosion rates (22–54 g m− 2 min− 1) with resuspended particle sizes ranging from 100 to 930 µm for all sites. There was no indication of biotic influence on sediment stability, although our cores did not display a fluff layer of unconsolidated sediment. Concurrent studies in the delta and shelf region suggest the importance of a nepheloid layer which transports suspended particles to the slope. Continuous cycles of resuspension, deposition, and horizontal advection may intensify with reduction of sea ice in this region. Our measurements coupled with studies of circulation and cross-shelf exchange allow parameterization and modeling of particle dynamics and carbon fluxes under various climate change scenarios. 相似文献
140.
The Northern Sea Route (NSR) has tremendous potential for ocean shipping between Europe and Asia due to the savings from shorter transit time and distance. However, the Arctic area is environmentally vulnerable and thus there is a trade-off between NSR’s impacts on environment vs. its economic benefits, especially when compared with the traditional route, such as through the Suez Canal Route (SCR). This study estimates the market shares of different transport modes and alternative shipping routes for the container transport market between Europe and Asia, and the resulting environmental costs. Our result suggests that NSR can be a viable option under the status quo. However, its environmental costs tend to be higher than SCR due to small ship size and low load factor in the present, thus the development of NSR would lead to worse environment outcomes. If these issues can be resolved, NSR can benefit from lower operational and environmental costs, which will lead to higher market share and social welfare. Otherwise, increased use of NSR may lead to higher total environment costs than the status quo. 相似文献