Identification of the Kuroshio Extension, its bifurcation and northern branch from altimetry and hydrographic data during October 1992–August 1999: Spatial and temporal variability

A methodology is proposed using altimter‐derived upper layer thickness and baroclinic transport to identify the Kuroshio Extension, the Bifurcation Point and the Northern Branch, by combining TOPEX/POSEIDON altimeter and climatological data within a two‐layer reduced gravity model. Results obtained from the Japanese coast to 175°W show that the location of the Bifurcation Point presents interannual variability that is related with upstream conditions. The longitude of the Bifurcation Point ranged from 147 to 160°E. Estimates of baroclinic transport at the Kuroshio Extension and its Northern Branch decrease steadily to the east trough the region of study from 35 to 11 and from 10 to 3 Sv, respectively.