Seasonal Variation in Volume Transport of the Kuroshio South of Japan

1994 ◽  
Vol 24 (2) ◽  
pp. 261-272 ◽  
Author(s):  
Yoshihiko Sekine ◽  
Kunio Kutsuwada
2006 ◽  
Vol 56 (5-6) ◽  
pp. 607-623 ◽  
Author(s):  
Norihisa Usui ◽  
Hiroyuki Tsujino ◽  
Yosuke Fujii ◽  
Masafumi Kamachi

2016 ◽  
Vol 33 (10) ◽  
pp. 2185-2203 ◽  
Author(s):  
Vigan Mensah ◽  
Magdalena Andres ◽  
Ren-Chieh Lien ◽  
Barry Ma ◽  
Craig M. Lee ◽  
...  

AbstractThis study presents amended procedures to process and map data collected by pressure-sensor-equipped inverted echo sounders (PIESs) in western boundary current regions. The modifications to the existing methodology, applied to observations of the Kuroshio from a PIES array deployed northeast of Luzon, Philippines, consist of substituting a hydrography-based mean travel time field for the PIES-based mean field and using two distinct gravest empirical mode (GEM) lookup tables across the front that separate water masses of South China Sea and North Pacific origin. In addition, this study presents a method to use time-mean velocities from acoustic Doppler current profilers (ADCPs) to reference (or “level”) the PIES-recorded pressures in order to obtain time series of absolute geostrophic velocity. Results derived from the PIES observations processed with the hydrography-based mean field and two GEMs are compared with hydrographic profiles sampled by Seagliders during the PIES observation period and with current velocity measured concurrently by a collocated ADCP array. The updated processing scheme leads to a 41% error decrease in the determination of the thermocline depth across the current, a 22% error decrease in baroclinic current velocity shear, and a 61% error decrease in baroclinic volume transports. The absolute volume transport time series derived from the leveled PIES array compares well with that obtained directly from the ADCPs with a root-mean-square difference of 3.0 Sv (1 Sv ≡ 106 m3 s–1), which is mainly attributed to the influence of ageostrophic processes on the ADCP-measured velocities that cannot be calculated from the PIES observations.


2001 ◽  
Vol 28 (1) ◽  
pp. 17-20 ◽  
Author(s):  
Shiro Imawaki ◽  
Hiroshi Uchida ◽  
Hiroshi Ichikawa ◽  
Masao Fukasawa ◽  
Shin-ichiro Umatani ◽  
...  

2021 ◽  
Vol 8 ◽  
Author(s):  
Zhiqiang Liu ◽  
Jianping Gan ◽  
Jianyu Hu ◽  
Hui Wu ◽  
Zhongya Cai ◽  
...  

This paper reviews recent advances in the circulation dynamics of the Kuroshio and its interaction with shelf currents in the East China Sea (ECS). The annually averaged Kuroshio volume transport varies between 19 and 24 Sv, based on different observations, but there is no consensus on which season its volume transport peaks. The Kuroshio is intensified over the central slope of the ECS from that off the northeast of Taiwan. The total Kuroshio intrusion into the ECS shelf is estimated to be 1.3–1.4 Sv, deduced from the observed volume transport of exchange flow in the Taiwan and Tsushima Straits, based on the assumption of volume conversation over the shelf. However, the uncertainty regarding this estimation remains due to the absence of sufficient observations and understanding of the Kuroshio dynamics. The Kuroshio intrusions over the shelf off the northeast of Taiwan and southwest of Kyushu are stimulated by planetary or topographic β -effect associated with the alongshore variations in the ECS slope topography and altered by variations in the Kuroshio intensity, shear stress, and baroclinicity. Multilayered exchanges between the Kuroshio and shelf currents were found between 100- and 200-m isobaths along the central ECS slope. The spatial variations in these exchanges are governed by cross-isobath transport by geostrophy, whereas bottom Ekman transport may play a predominant role in altering the integrated exchange flow along the slope. Although the intrusion is greatly modulated along the path of the Kuroshio in the ECS by variable slope topography, there are few observations on the spatial variations of these exchange flows. The characteristics and variations in the circulation and hydrographic properties of waters between 100- and 200-m isobaths significantly determine the general ECS circulation, about which consensus has still not been attained.


Sign in / Sign up

Export Citation Format

Share Document