Synoptic features of the Kuroshio at 23.75 N were quantified using nine ship-based surveys between September 2012 and September 2014. The new ship-based data set provides an unprecedented view of the Kuroshio east of Taiwan and suggest tremendous variability in its velocity, hydrography, volume, heat, and salt transports, and water masses. The Kuroshio maximum velocity varied in 0.7-1.4 m s 21 ; the core current width, delineated with the limit v 0.2 m s 21 , ranged from 85 to 135 km, and the thickness varied from 400 to 600 m. A dual velocity maximum in the Kuroshio core current, though unexpected, was observed in three of nine cruises. The Kuroshio core transport, integrated from the directly measured velocity, varied between 10.46 and 22.92 Sv (1 Sv510 6 m 3 s 21 ). The corresponding heat transport referenced to 0 C was 0.838-1.793 3 10 15 W, and the salt transport was 345.0-775.9 3 10 6 kg s 21 . The geostrophic transport estimated using the thermal wind relation with the observed hydrographic data and reference velocity at 900 m is comparable to the directly measured Kuroshio transport during most of the surveys, suggesting the directly measured velocity is mostly in geostrophic balance.

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[1] A three-dimensional model driven by tidal constituents O 1 , K 1 , M 2 and S 2 was adopted to evaluate the sources of baroclinic tidal energy in the Gaoping Submarine Canyon (GPSC) off southwestern Taiwan. The model domain covered the probable primary generation sites, including the Luzon Strait (LS) and the southeastern Taiwan Strait (TS). The simulated baroclinic tides agreed with the observations of tidal current velocity, isotherm vertical displacement, and baroclinic tidal energy flux (F bc ) in the GPSC. The depth-integrated, seven-day-averaged F bc computed from the model result was 2.2 kW m −1 in the GPSC, and the corresponding area-integrated F bc reached 189.4 MW. The results obtained from the model suggest that the baroclinic tides lead to strong turbulent mixing near the canyon head with a vertical diffusivity of 3.5 × 10 −3 m 2 s −1 . Baroclinic tidal energy in the GPSC is mainly generated on the western ridge in the LS and on the steep topography in the southeastern TS. The local generation of baroclinic energy only accounts for 4.4% of the total value. The other 95.6% of the baroclinic tidal energy is remotely generated at the LS and the southeastern TS of which 31.9% and 8.8% are directly emanated, respectively, into the GPSC. The northwestward and southeastward baroclinic energy beams radiating from the LS and the southeastern TS, respectively, meet each other and form internal partial standing tides outside the GPSC. The transverse baroclinic energy from the internal partial standing tides accounts for the remaining 54.9% of the baroclinic tidal energy in the GPSC.

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