[A-CG32] Extratropical oceans and atmosphere

[ACG32-P12] Underwater glider observation of Kuroshio and its extension region

*Katsuya Toyama¹, Naohiro Kosugi¹, Masao Ishii¹, Hiroyuki Tsujino¹, Ono Hisashi¹ (1.Meteorological Research Institute)

Keywords:ocean glider, Kuroshio

The ocean glider is a buoyancy driven autonomous underwater vehicle which moves both vertically and horizontally in a sawtooth trajectory toward a specified waypoint. The unique capacities of the gliders are suitable for observing some key aspects of the ocean including the boundary currents, complementing the existing components of the Global Ocean Observing System such as Argo and ship-board measurements. The Kuroshio off Taiwan has been frequently observed by gliders as part of the Boundary Ocean Observing Network of the international OceanGliders program, however, the Kuroshio and its extension (KE) region has rarely been observed by gliders.
Using a glider equipped with CTD, oxygen (RINKO II), and bio-optical (ECO FLBBCD) sensors, we have conducted hydrographic and biogeochemical observations of the Kuroshio and KE region southeast of Japan from 16 November, 2023 to 18 January, 2024. After having been deployed at offshore south of Niijima Island, Tokyo from a small ship (Tsukuba II of Shimoda Marine Research Center, University of Tsukuba), the glider traveled across the Kuroshio and an anticyclonic eddy located at the south of the first KE ridge. The glider has just drifted at the surface due to mechanical trouble since 7 December, 2023 but successfully been recovered by Keifu-maru of the Japan Meteorological Agency on 18 January, 2024.