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11.
Impacts of rising air temperatures and emissions mitigation on electricity demand and supply in the United States: a multi-model comparison 总被引:2,自引:2,他引:0
12.
This study is based on a series of numerical modeling experiments to understand the tidal circulation in the Kangjin Bay (KB).
The tidal circulation in the KB is mostly controlled by the inflow from two channels, Noryang and Daebang which introduce
the open ocean water into the northern part of the KB with relatively strong tidal current, while in the southern part of
the KB, shallowest region of the entire study area, weak tidal current prevails. The model prediction of the sea level agrees
with observed records at skill scores exceeding 90 % in terms of the four major tidal constituents (M2, S2, K1, O1). However,
the skill scores for the tidal current show relatively lower values of 87, 99, 59, 23 for the semi-major axes of the constituents,
respectively. The tidal ellipse parameters in the KB are such that the semi-major axes of the ellipse for M2 range from 1.7
to 38.5 cm/s and those for S2 range from 0.5 to 14.4 cm/s. The orientations of the major-axes show parallel with the local
isobath. The eccentricity values at various grid points of ellipses for M2 and S2 are very low with 0.2 and 0.06 on the average,
respectively illustrating that the tidal current in the KB is strongly recti-linear. The magnitude of the tidal residual current
speed in the KB is on the order of a few cm/s and its distribution pattern is very complex. One of the most prominent features
is found to be the counter-clockwise eddy recirculation cell at the mouth of the Daebang Channel. 相似文献
13.
Scoping the effective marine environmental assessment of dredging and ocean disposal of coastal sediments in Korea 总被引:1,自引:0,他引:1
The application of scoping is reviewed to improve the efficiency and rationality of the marine environmental impact assessment system applied to the dredging of coastal sediments and the oceanic disposal of dredged material in Korea. Both the impact levels and those items requiring assessment vary in response to differing goals of the coastal activities involved and also to changes in the characteristics of different marine environments. As a consequence, different assessment fields need to be emphasized for evaluation of the impact that both dredging and dumping might have on the sites involved. The status of current assessment procedures is examined and its problems are diagnosed. Following a survey of interested parties and a review of case studies of the oceanic disposal of dredged sediment in other countries, checklists of core assessment items are proposed as part of a revamped review process, along with improvements to the assessment system. 相似文献
14.
Kim Jin Ho Hong Sokjin Lee Won-Chan Kim Hyung Chul Eom Ki-Hyuk Jung Woo-Sung Kim Dong-Myung 《Ocean Science Journal》2019,54(4):559-571
Ocean Science Journal - Flushing time is a concept to show the characteristics of water exchange in the sea, and a longer flushing time generally translates as delayed water exchange and thus a... 相似文献
15.
Norikatsu Akizawa Akira Miyake Yohei Igami Akira Tsuchiyama Hisashi Asanuma Tetsu Kogiso Shigeyuki Wakaki Tsuyoshi Ishikawa Shoji Arai Jiwon Eom Hodaka Kawahata Takahiro Aze Yusuke Yokoyama 《Island Arc》2021,30(1):e12423
Hydrothermal circulation beneath the spreading axis plays a significant role in the exchange of energy and mass between the solid Earth and the oceans. Deep-seated hydrothermal circulation down to the crust/mantle boundary in the fast-spreading axis has been introduced by a number of studies regarding geological investigations and numerical models. In order to assess a reaction between hydrothermal fluid and host rock around the crust/mantle boundary, we conducted bulk trace element and Sr isotope analyses with a series of in situ investigations for crustal anorthosite, a reaction product between hydrothermal fluid and gabbro in the lowermost crustal section along Wadi Fizh, northern Oman ophiolite. In addition, we conducted titanite U–Pb isotope analyses to evaluate timing of the crustal anorthosite formation in the framework of the evolutional process of the Oman ophiolite. We estimated the formation age of the crustal anorthosite at 97.5 Ma ± 5.0 Ma, overlapping with the timing of the crust formation in the paleo spreading axis. The crustal anorthosite shows high-Th/U ratio (~2.5) and high-initial 87Sr/86Sr ratio (0.7050) due to seawater-derived hydrothermal fluid ingress into the precursor gabbro. With using analytical technique of micro-excavation at cryo-temperature, we detected Cl from a few micrometer-sized inclusion of aqueous fluid and chromite grains. The solubility of Cr was enhanced by complexation reactions with Cl in the hydrothermal fluid. Regarding reconstructed three-dimensional mass distribution of the inclusion and chromite composition, maximum Cr content of parental fluid was estimated at ~69 000 μg/g. The exceptionally high-Cr content was achieved locally by leaking of fluid and synchronous chromite crystallization during fluid entrapment. Presence of the deep-seated hydrothermal circulation could be assigned to the segment end, where cold seawater penetrates into the lowermost crust and extract heat along widely spaced network-like fluid channel. 相似文献
16.
Shin Euntaek Kim Hyung-Jun Rhee Dong Sop Eom Taesoo Song Chang Geun 《Natural Hazards》2021,109(2):1539-1555
Natural Hazards - Underground space is becoming increasingly vulnerable to inundation owing to the enhanced likelihood and consequences of urban flooding. However, previous studies on flooding of... 相似文献