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Rolando S. Balotro Atsuhiko Isobe Manabu Shimizu Atsushi Kaneda Takatoshi Takeuchi Hidetaka Takeoka 《Journal of Oceanography》2002,58(6):759-773
An attempt was made to reproduce the circulation pattern in Suo-Nada, Japan during spring and summer season in order to elucidate
the water exchange mechanism in the basin. Two hydrographic surveys at the end of each season were conducted covering the
entire Suo-Nada area. A three-dimensional hydrodynamic Princeton Ocean Model (POM) was used to compute the current resulting
from the observed density and wind field. During spring, a very pronounced counter clockwise gyre is situated near the opening
of the basin. This is replaced by a clockwise circulation which seemed to occupy the whole domain during summer. Within each
season, however, the vertical distribution of current does not show any remarkable differences, indicating the dominance of
horizontal current and a very weak estuarine flow. These observational and numerical results were used to estimate the remnant
function and the corresponding average residence time of permanently dissolved matter (PDM) and transformable matter (TM).
The results revealed a small difference in the average residence times of materials within each season but a large seasonal
variability between spring and summer. Furthermore, calculations based on climatological density fields have indicated a similar
trend of variation between the seasonal values of average residence times.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Irizuki T Takimoto A Sako M Nomura R Kakuno K Wanishi A Kawano S 《Marine pollution bulletin》2011,62(10):2030-2041
This study focuses on the relationships of water and sediment quality with meiobenthos (Ostracoda) over the past 100 years, using a sediment core obtained from Suo-Nada in the Seto Inland Sea, Japan. We compared high-resolution ostracode results with geochemical and sedimentological data obtained from the study core as well as with rich environmental monitoring data that are available. R-mode cluster analysis revealed two bioassociations (BC, KA). Until the1960s, assemblages continued to show high diversity. They changed in approximately 1970, when excessive nutrients and organic matter began to be supplied, and most species decreased in number. All species of bioassociation BC were dominant again by the mid-1990s; however, those of bioassociation KA containing infaunal species did not increase and have been absent or rare since the 1970s because organic pollution of sediments has continued to date. This study provided robust baseline for ostracode-based long-term environmental monitoring in East Asia. 相似文献
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The behavior of a river plume in Suo-Nada, Japan, has been studied using a primitive equation numerical model, the Princeton
Ocean Model. Special attention has been paid to the current structure and behavior of the anticyclonic eddy (bulge) induced
by high freshwater inflow changing on a timescale of one week. First, the freshwater is supplied from a river to a rectangular
basin with a simple topography. When the river discharge subsides after reaching its peak value, the bulge propagates upstream
(i.e., opposite to the direction of the Kelvin wave propagation). Next, the freshwater is supplied from eight major rivers
to the basin with realistic topography. The less saline water mass in the southern part of Suo-Nada propagates to the west
(i.e., upstream) after the river discharge subsides. This is consistent with an observed phenomenon, viz., that the less saline
water mass appears in the western part of Suo-Nada, suggesting that the upstream propagation of the bulge is possible in the
real ocean. Finally, the cause of the upstream propagation is considered. Onshore currents appear in the bottom layer beneath
the bulge, propagating upstream. They produce an anticyclonic barotropic eddy due to the conservation of potential vorticity.
The current component associated with the eddy crosses normally to the isohaline in the upper layer, and therefore transports
the bulge upstream. No other current component (such as surface current velocity minus vertically-averaged value) is responsible
for the upstream propagation of the bulge.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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