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Data on the Tsushima Current and its neighboring coastal current are analyzed to examine short-term variability of the currents and storm events due to typhoons. A three current-meter array was deployed in a strong current region of the east Tsushima channel during summer in 1983 and 1984, and other two current-meter arrays in the eastern coastal area of the channel (the Sea of Genkai) in the summer and autumn in 1983. The observations of coastal current show that the kinetic energy of the subtidal current component was larger in summer than in autumn by a factor of about 2. A comparison of the wind stresses and the estimated values of mixed layer depth in the summer and autumn season suggest that this seasonal change is closely associated with that of the mixed layer depth rather than with that of the wind stress. The Tsushima Current was greatly influenced by two storm events: its speed increased by a factor of 2 in one event and decreased to nearly zero in the other. Such a large variation of mean current during the storm was observed only for the Tsushima Current and not for the coastal current, suggesting that the Tsushima Current may temporarily change its regular course as a result of a storm. 相似文献
885.
S. Thomas Crough 《Marine Geophysical Researches》1982,5(3):263-271
Geoid height anomalies, as determined by satellite altimetry, suggest that the Cape Verde Rise is in local isostatic equilibrium, supported by a low-density root of altered lithosphere. A depth anomaly map shows the Cape Verde Rise to be approximately 1600 km wide and 2km high. Removal of a quadratic surface from the observed geoid heights leaves a residual positive anomaly with the same shape as the rise and an amplitude of about 8 m. The ratio of residual geoid height anomaly to depth anomaly is consistent with an isostatic root only 40 km deep on average. 相似文献
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D. R. Burton 《Ocean Engineering》1983,10(1):33-45
The exothermic reaction which proceeds when small sachets containing particulate mixtures of iron and magnesium are flooded with sea water, has been used for thermal support of free divers. Initial application of such generators to heating of the hands (Burton and Chan, 1981), and later extension to heating of the torso, have been described previously (Chan and Burton, 1981, 1982). Of considerable interest during field trials of the torso heating system was a strong subjective impression among those taking part, that significant increases of dive duration and decreases of perceived discomfort could be obtained with relatively low levels of power generation, for example less than 50% of that required for thermal balance. In this paper, a simple mathematical model of human stored heat loss is used to rationalize this observation. Also it successfully predicts voluntary exposure times of unheated divers who become cold. When used to estimate body heat debt, the model enables documented dives by this laboratory and by others, including recent exposures in Antarctica using low level supplementary heating, to be analysed. 相似文献
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890.
M. Arockiasamy H. El-Tahan A.S.J. Swamidas W.E. Russell D.V. Reddy 《Ocean Engineering》1984,11(5):463-490
The paper presents an analytical and experimental study on the transient response of semisubmersibles to bergybit impact and the strength of bergybit ice to high strain-rate loadings. Two approaches have been proposed for the solution of the semisubmersible-bergybit interaction problem, one using the energy approach and the other using the conventional structural dynamics approach with initial velocity conditions. In addition the local behaviour of the impacted regions have been analysed for deformation and failure. Numerical results have been given for local behaviour of an impacted column and global behaviour of semisubmersible-bergybit system. Experimental study has been reported on the impact strength of iceberg ice at strain rates of 10−3, 10−2 and 10−1; the indentation impact strength of ice is found to be 3–4 times the unaixial compressive strength, at the same strain rate. 相似文献