ZHOU Feng, XUAN Jiliang, NI Xiaobo, HUANG Daji. A preliminary study of variations of the Changjiang Diluted Water between August of 1999 and 2006[J]. Acta Oceanologica Sinica, 2009, (6): 1-11.
Citation:
ZHOU Feng, XUAN Jiliang, NI Xiaobo, HUANG Daji. A preliminary study of variations of the Changjiang Diluted Water between August of 1999 and 2006[J]. Acta Oceanologica Sinica, 2009, (6): 1-11.
ZHOU Feng, XUAN Jiliang, NI Xiaobo, HUANG Daji. A preliminary study of variations of the Changjiang Diluted Water between August of 1999 and 2006[J]. Acta Oceanologica Sinica, 2009, (6): 1-11.
Citation:
ZHOU Feng, XUAN Jiliang, NI Xiaobo, HUANG Daji. A preliminary study of variations of the Changjiang Diluted Water between August of 1999 and 2006[J]. Acta Oceanologica Sinica, 2009, (6): 1-11.
Department of Fluid Mechanics, School of Aeronautics and Astronautics of Zhejiang University, Hangzhou 310027, China;State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, State Oceanic Administration, Hangzhou 310012, China
2.
State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, State Oceanic Administration, Hangzhou 310012, China
A large area hypoxia has been already reported respectively by two interdisciplinary surveys off the Changjiang Estuary since summer of 1999 and 2006. The hypoxic zone shows distinct year-to-year variations. Observed oceanographic data are first analysized and reveal a big difference for the Changjiang Diluted Water (CDW) between these two periods. These great changes are related to the tremendous reduction of the freshwater discharge and variations of wind fields between these two years. It is also found that the monthly mean intrusion of Kuroshio and its branches has increased in the northern East China Sea (ECS), but decreased in the southern ECS in August of 2006 as compared with 1999 on the base of general circulation models. Then, the Regional Ocean Modelling Systems is applied to the East China Sea to evaluate the contributions and relative importance of impacts from the river discharge, wind forcing and open boundary data. Our simulations reproduce the phenomena that more fresh water extends northeastward in 2006 and forms a negative SSS anomaly to the northeast of the river mouth as compared with 1999, which is consistent with observations. The five group numerical tests suggest that the wind forcing dominates the CDW variations followed by the Kuroshio and its branches. The study implies important roles played by hydrodynamic processes on the variability of hypoxic zone in the study areas.
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