The gridded (1/3°*1/3°) altimetry data from October 1992 through December 2004 were analyzed to study the seasonal and interannual variabilities of the bifurcation of the North Equatorial Current (NEC) ...The gridded (1/3°*1/3°) altimetry data from October 1992 through December 2004 were analyzed to study the seasonal and interannual variabilities of the bifurcation of the North Equatorial Current (NEC) at the surface in the western North Pacific Ocean. Calculations show that on annual average the bifurcation occurs at about 13.4°N at the surface. The geostrophic flow derived from Sea Surface Height (SSH) data shows that the southernmost latitude of the NEC bifurcation at the surface is about 12.9°N in June and the northernmost latitude is about 14.1°N in December. Correlation analyses between the bifurcation latitude and the Southern Oscillation Index (SOl) suggest that the bifurcation latitude is highly correlated with the E1 Nino/Southern Oscillation (ENSO) events. During the E1 Nino years the bifurcation of the NEC takes place at higher latitudes and vice versa.展开更多
The Simple Ocean Data Assimilation (SODA) package is used to better understand the variabilities of surface current transport in the Tropical Pacific Ocean from 1950 to 1999. Seasonal variation, interannual and decada...The Simple Ocean Data Assimilation (SODA) package is used to better understand the variabilities of surface current transport in the Tropical Pacific Ocean from 1950 to 1999. Seasonal variation, interannual and decadal variability analyses are conducted on the three major surface currents of the Tropical Pacific Ocean: the North Equatorial Current (NEC), the North Equatorial Countercurrent (NECC), and the South Equatorial Current (SEC). The transport of SEC is quite larger than those of NEC and NECC. The SEC has two maximums in February and August. The NEC has a small annual variation. The NECC has a maximum in October and is very weak in March and April. All currents have remarkable interannual and decadal variabilities. The variabilities of the NEC and the SEC relate to the winds over them well, but the relationship between the NECC and the wind over it is not close. Analysis related to El Nio-Southern Oscillation (ENSO) suggests that before El Nio (La Nia) the SEC is weaker (stronger) and the NECC is stronger (weaker), after El Nio (La Nia) the SEC is stronger (weaker) and the SEC is weaker (stronger). There is no notable relationship between the NEC and ENSO.展开更多
基金Project supported by the National Natural Science Foundation of China (Grants Nos: D06-40552002, 40576016) the Qingdao Municipal Bureau of Science and Technology (Grant No: 02-KJYSH-03).
文摘The gridded (1/3°*1/3°) altimetry data from October 1992 through December 2004 were analyzed to study the seasonal and interannual variabilities of the bifurcation of the North Equatorial Current (NEC) at the surface in the western North Pacific Ocean. Calculations show that on annual average the bifurcation occurs at about 13.4°N at the surface. The geostrophic flow derived from Sea Surface Height (SSH) data shows that the southernmost latitude of the NEC bifurcation at the surface is about 12.9°N in June and the northernmost latitude is about 14.1°N in December. Correlation analyses between the bifurcation latitude and the Southern Oscillation Index (SOl) suggest that the bifurcation latitude is highly correlated with the E1 Nino/Southern Oscillation (ENSO) events. During the E1 Nino years the bifurcation of the NEC takes place at higher latitudes and vice versa.
基金This research was supported by the National Natural Science Foundation of China(Grant Nos.40176003 and 40136010)Anna Zaklikowski was supported by the funding of the U.S.National Science Foundation
文摘The Simple Ocean Data Assimilation (SODA) package is used to better understand the variabilities of surface current transport in the Tropical Pacific Ocean from 1950 to 1999. Seasonal variation, interannual and decadal variability analyses are conducted on the three major surface currents of the Tropical Pacific Ocean: the North Equatorial Current (NEC), the North Equatorial Countercurrent (NECC), and the South Equatorial Current (SEC). The transport of SEC is quite larger than those of NEC and NECC. The SEC has two maximums in February and August. The NEC has a small annual variation. The NECC has a maximum in October and is very weak in March and April. All currents have remarkable interannual and decadal variabilities. The variabilities of the NEC and the SEC relate to the winds over them well, but the relationship between the NECC and the wind over it is not close. Analysis related to El Nio-Southern Oscillation (ENSO) suggests that before El Nio (La Nia) the SEC is weaker (stronger) and the NECC is stronger (weaker), after El Nio (La Nia) the SEC is stronger (weaker) and the SEC is weaker (stronger). There is no notable relationship between the NEC and ENSO.