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Cite this paper: |
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ZHANG Yanwei, XU Huiping, QIN Rufu, XU Changwei, FAN Daidu. Characteristics of turbulent kinetic energy dissipation rate and turbidity near the coast of East China Sea[J]. Journal of Oceanology and Limnology, 2016, 34(5): 1134-1142 |
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Characteristics of turbulent kinetic energy dissipation rate and turbidity near the coast of East China Sea |
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| ZHANG Yanwei, XU Huiping, QIN Rufu, XU Changwei, FAN Daidu |
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| State Key Lab of Marine Geology, Tongji University, Shanghai 200092, China |
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| Abstract: |
| The East China Sea (ECS) has a high suspended-sediment concentration because of the influence of the Changjiang River, indicated by high turbidity in the water. Considering the islands off the coast and the complex topography, and the strong influence of tides and wind, the coast off the ECS is a typical region with strong oceanic mixing processes. The changes in the dynamic processes near the bottom play an important role in the control of water turbidity. The turbulent kinetic energy dissipation rate (ε) is a parameter that shows the strength of ocean mixing. This is estimated based on a structure method using current velocity that is measured by a high-frequency Acoustic Doppler Current Profiler (ADCP) from a seafloor observatory in the ECS. The results indicate strong ocean mixing processes with a mean ε value of 5.7×10-5 W/kg and distinct tidal variations in the dissipation rate. Conversely, the variation of the water turbidity leads to changes in the water dynamical structure near the bottom. Comparing the dissipation rate with the turbidity near the bottom boundary layer, we find that the high turbidity mimics strong ocean mixing. |
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| Key words:
turbulent kinetic energy dissipation rate|turbidity|tides|near bottom boundary|East China Sea
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| Received: 2014-11-13 Revised: 2015-04-27 |
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