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Hirokazu Ozaki Hajime Obata Mikio Naganobu Toshitaka Gamo 《Journal of Oceanography》2009,65(2):235-244
We measured potential temperature, salinity, and dissolved oxygen profiles from the surface to the bottom at two locations
in the north Ross Sea (65.2°S, 174.2°E and 67.2°S, 172.7°W) in December 2004. Comparison of our data with previous results
from the same region reveals an increase in potential temperature and decreases in salinity and dissolved oxygen concentration
in the bottom layer (deeper than 3000 m) over the past four decades. The changes were significantly different from the analytical
precisions. Detailed investigation of the temperature, salinity, dissolved oxygen and σ
3 value distributions and the bottom water flow in the north Ross Sea suggests a long-term change in water mass mixing balance.
That is to say, it is speculated that the influence of cool, saline, high-oxygen bottom water (high-salinity Ross Sea Bottom
Water) formed in the southwestern Ross Sea has possibly been decreased, while the influences of relatively warmer and fresher
bottom water (low-salinity Ross Sea Bottom Water) and the Adélie Land Bottom Water coming from the Australia-Antarctic Basin
have increased. The possible impact of global warming on ocean circulation needs much more investigation. 相似文献
104.
SONG Zhiyao XUE Hongchao YAN Yixin
Doctor Senior Engineer College of Harbor Waterway Coastal Engineering Hohai University 《中国海洋工程》1999,(4)
To deal with the problems concerning the shore boundary,moving boundary and engineeringboundary which are encountered frequently in 2D tidal current simulation by the finite difference method,theconcept of line boundary is introduced and studied here,and then the line boundary technique in common useis proposed in this paper.Analysis of some calculation cases shows that this technique is practical,effective,and simple in 2D tidal current simulation involving different boundaries. 相似文献
105.
In this paper the probability of green water occurrence is investigated by taking into account the threshold of the vertical relative motion exceeding the freeboard. The number of wetting of the unit/vessel is predicted using probabilistic method. This paper compares the significant load, due to shipping of green water with the works of other researchers, and the loads are found to be close with the results presented in this paper. There is no direct relation between the velocities in the waves and the water velocity over the deck. The water velocities around the bow are heavily distributed by the presence of the bow. This scenario makes the flow very complex for schematic modelling. 相似文献
106.
福建沿海地区水资源紧缺问题及其解决途径 总被引:4,自引:1,他引:4
本文针对福建沿海地区存在的水资源紧问题,通过对福沿海地区水资源数量,供需平衡的分析探讨了水资源紧缺问题存在的主要原因,并结合水资源利用的现状特征,进一步深入评述了现状利用中存在的问题,最后从可持续利用水资源的角度出发,重点讨论解决途径。 相似文献
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In this paper the water-taking characteristics of the first,the second and the third stage of theHuanghua Power Plant are studied by numerical model and physical model.The results show that the pres-ent inlet channel only satisfies the supply need of the first stage of the power plant.If the riverbed of the in-let reach is properly dredged,the need of water supply for the third stage of the power plant could be met. 相似文献
109.
海洋沉积物孔隙水中阴阳离子含量的离子色谱法分析方法 总被引:2,自引:0,他引:2
分别采用Metrosep A Supp4-250型阴离子柱和Metrosep C 2-150型阳离子柱,以1.8 mmol/L Na2CO3 1.7 mmol/L NaHCO3和4 mmol/L酒石酸 0.75 mmol/L吡啶二羧酸为阴阳离子淋洗液,用离子色谱仪来测定海洋沉积物孔隙水中阴离子Cl-、Br-和SO42-浓度和阳离子Na 、NH4 、K 、Ca2 、Mg2 的浓度。特别是针对高Cl-和高Na 背景下Br-和NH4 的测定做了专门分析,得到了较理想的结果,建立了一套离子色谱法测定海洋沉积物孔隙水中常见的阴阳离子含量的实验方法。 相似文献
110.