Mean transport and seasonal cycle of the Kuroshio east of Taiwan with comparison to the Florida Current

Thomas N. Lee, William E Johns, Cho Teng Liu, Dongxiao Zhang, Rainer Zantopp, Yih Yang

Research output: Contribution to journalArticle

69 Citations (Scopus)

Abstract

Moored observations of Kuroshio current structure and transport variability were made across the channel between northeast Taiwan and the Ryukyu Islands at 24° N from September 19, 1994, to May 27, 1996. This was a cooperative effort between the United States and Taiwan. The moored array was designated PCM-1, for the World Ocean Circulation Experiment (WOCE) transport resolving array. The dominant current and transport variability occurred on 100-day timescales and is shown by Zhang et al. [2001] to be caused by warm mesoscale eddys merging with the Kuroshio south of the array causing offshore meandering and flow splitting around the Ryukyu Islands. An annual transport cycle could not be resolved from our 20-month moored record because of aliasing from the 100-day period events. Sea level difference data were used to extend the transport time series to 7 years giving a variation in the range of the annual transport cycle of 4-10 Sv, with a mean range closer to 4 Sv. The seasonal maximum of 24 Sv occurred in the summer and the seasonal minimum of 20 Sv occurred in the fall. A weaker secondary maximum also occurred in the winter. The cycle of Kuroshio transport appears to result from a combination of local along-channel wind forcing and Sverdrup forcing over the Philippine Sea. Our estimate of the mean transport of the Kuroshio at the entrance to the East China Sea from the moored array is 21.5 ± 2.5 Sv. The mean transpacific balance of meridional flows forced by winds and thermohaline processes at this latitude requires an additional mean northward flow of 12 Sv with an annual cycle of ±8 Sv along the eastern boundary of the Ryukyu Islands. The mean transport and annual cycle of the Kuroshio were found to be in reasonable agreement with basin-scale wind-forced models. Remarkable similarities are shown to exist between the mean western boundary currents and their seasonal cycles in the Atlantic (Florida Current and Antilles Current) and Pacific (Kuroshio and boundary current east of Ryukyu Island chain) at the same latitude. However, detailed comparison shows that the mean Kuroshio is weaker and more surface intensified than the mean Florida Current, while the Kuroshio transport variability is significantly larger.

Original languageEnglish (US)
Article number2000JC000535
Pages (from-to)22143-22158
Number of pages16
JournalJournal of Geophysical Research C: Oceans
Volume106
Issue numberC10
StatePublished - Oct 15 2001

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Taiwan
cycle transport
cycles
annual cycle
Pulse code modulation
Sea level
Merging
boundary current
western boundary current
Time series
wind forcing
sea level
time series
meridional flow
timescale
Philippines
comparison
winter
summer
Experiments

ASJC Scopus subject areas

  • Geochemistry and Petrology
  • Geophysics
  • Earth and Planetary Sciences (miscellaneous)
  • Space and Planetary Science
  • Atmospheric Science
  • Astronomy and Astrophysics
  • Oceanography

Cite this

Lee, T. N., Johns, W. E., Liu, C. T., Zhang, D., Zantopp, R., & Yang, Y. (2001). Mean transport and seasonal cycle of the Kuroshio east of Taiwan with comparison to the Florida Current. Journal of Geophysical Research C: Oceans, 106(C10), 22143-22158. [2000JC000535].

Mean transport and seasonal cycle of the Kuroshio east of Taiwan with comparison to the Florida Current. / Lee, Thomas N.; Johns, William E; Liu, Cho Teng; Zhang, Dongxiao; Zantopp, Rainer; Yang, Yih.

In: Journal of Geophysical Research C: Oceans, Vol. 106, No. C10, 2000JC000535, 15.10.2001, p. 22143-22158.

Research output: Contribution to journalArticle

Lee, TN, Johns, WE, Liu, CT, Zhang, D, Zantopp, R & Yang, Y 2001, 'Mean transport and seasonal cycle of the Kuroshio east of Taiwan with comparison to the Florida Current', Journal of Geophysical Research C: Oceans, vol. 106, no. C10, 2000JC000535, pp. 22143-22158.
Lee, Thomas N. ; Johns, William E ; Liu, Cho Teng ; Zhang, Dongxiao ; Zantopp, Rainer ; Yang, Yih. / Mean transport and seasonal cycle of the Kuroshio east of Taiwan with comparison to the Florida Current. In: Journal of Geophysical Research C: Oceans. 2001 ; Vol. 106, No. C10. pp. 22143-22158.
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