An assimilation data set based on the GFDL MOM3 model and the NODC XBT data set is used to examine the circulation in the western tropical Pacific and its seasonal variations. The assimilated and observed velocities a...An assimilation data set based on the GFDL MOM3 model and the NODC XBT data set is used to examine the circulation in the western tropical Pacific and its seasonal variations. The assimilated and observed velocities and transports of the mean circulation agree well. Transports of the North Equatorial Current (NEC), Mindanao Current (MC), North Equatorial Countercurrent (NECC) west of 140°E and Kuroshio origin estimated with the assimilation data display the seasonal cycles, roughly strong in boreal spring and weak in autumn, with a little phase difference. The NECC transport also has a semi-annual fluctuation resulting from the phase lag between seasonal cycles of two tropical gyres’ recirculations. Strong in summer during the southeast monsoon period, the seasonal cycle of the Indonesian throughflow (ITF) is somewhat different from those of its upstreams, the MC and New Guinea Coastal Current (NGCC), implying the monsoon’s impact on it.展开更多
The seasonal circulation in the southeastern Huanghai Sea has been studied with hydrographic data,which were observed in February and June 1994 and bimonthly during 1970 - 1990, and numerical model results.Horizontal ...The seasonal circulation in the southeastern Huanghai Sea has been studied with hydrographic data,which were observed in February and June 1994 and bimonthly during 1970 - 1990, and numerical model results.Horizontal distributions of tempersture and salinity in 1994 are quite different due to strong tidal mixing so that weneed a analysis to see the real distributions of water masses. The mixing ratio analysis with the data of 1970 - 1990shows the connection of the waters in the west coasts of Korea Peninsula with warm and saline waters from the southin summer, which means northward inflows along the west coasts of Korea Peninsula in summer. With this flow, theseasonal circulations, which are deduced from the seasonal change of water mass distributions in the lower layer, arewarm inflows in winter and cold outflows in summer in the central Huanghai Sea, and cold outflows in winter andwarm inflows in summer along the west coasts of Korea Peninsula. The seasonall changed inflows might be theHuanghai Sea Warm Current. The monsoon winds can drive such circulations. However, summer monsoon winds areweak and irregular. As one of other possible dynamics, the variation of Kuroshio transport is numerically studied withallowing sea level fluctuations. Although it should be studied more, it possibly drives the summer circulations. The realcirculations seem to be driven by both of them.展开更多
基金This work was supported by the State Key Basic Research Development Project (Grant No. G1999043808)the Knowledge Innovation Project of the Chinese Academy of Sciences (Grant No. KZCX2-205)the National Natural Science Foundation of China (Grant Nos. 4
文摘An assimilation data set based on the GFDL MOM3 model and the NODC XBT data set is used to examine the circulation in the western tropical Pacific and its seasonal variations. The assimilated and observed velocities and transports of the mean circulation agree well. Transports of the North Equatorial Current (NEC), Mindanao Current (MC), North Equatorial Countercurrent (NECC) west of 140°E and Kuroshio origin estimated with the assimilation data display the seasonal cycles, roughly strong in boreal spring and weak in autumn, with a little phase difference. The NECC transport also has a semi-annual fluctuation resulting from the phase lag between seasonal cycles of two tropical gyres’ recirculations. Strong in summer during the southeast monsoon period, the seasonal cycle of the Indonesian throughflow (ITF) is somewhat different from those of its upstreams, the MC and New Guinea Coastal Current (NGCC), implying the monsoon’s impact on it.
文摘The seasonal circulation in the southeastern Huanghai Sea has been studied with hydrographic data,which were observed in February and June 1994 and bimonthly during 1970 - 1990, and numerical model results.Horizontal distributions of tempersture and salinity in 1994 are quite different due to strong tidal mixing so that weneed a analysis to see the real distributions of water masses. The mixing ratio analysis with the data of 1970 - 1990shows the connection of the waters in the west coasts of Korea Peninsula with warm and saline waters from the southin summer, which means northward inflows along the west coasts of Korea Peninsula in summer. With this flow, theseasonal circulations, which are deduced from the seasonal change of water mass distributions in the lower layer, arewarm inflows in winter and cold outflows in summer in the central Huanghai Sea, and cold outflows in winter andwarm inflows in summer along the west coasts of Korea Peninsula. The seasonall changed inflows might be theHuanghai Sea Warm Current. The monsoon winds can drive such circulations. However, summer monsoon winds areweak and irregular. As one of other possible dynamics, the variation of Kuroshio transport is numerically studied withallowing sea level fluctuations. Although it should be studied more, it possibly drives the summer circulations. The realcirculations seem to be driven by both of them.