Yuki Tanaka's Website

Faculty of Marine Science and Technology, Fukui Prefectural University

Associate Professor / Physical Oceanographer

Yuki TANAKA

PROFILE

• Name: Yuki TANAKA
• Date of Birth: July 2, 1981
• Place of Birth: Sayama-shi, Saitama-ken, Japan

OFFICE ADDRESS

• Faculty of Marine Science and Technology, Fukui Prefectural University
• 1-1 Gakuen-cho, Obama City, Fukui 917-0003, Japan
• Phone: +81-770-52-9622
• E-mail: y-tanaka (at) fpu.ac.jp

EDUCATION

	Ph.D.	Graduate School of Science, The University of Tokyo, Tokyo, Japan, March 2010.
		Thesis title: Evaluation of tidal mixing in the Kuril Straits and its impact on the formation of North Pacific Intermediate Water
		Thesis supervisor: Professor Toshiyuki Hibiya
	M.S.	Graduate School of Science, The University of Tokyo, Tokyo, Japan, March 2007.
	B.S.	Graduate School of Science, The University of Tokyo, Tokyo, Japan, March 2005.

EMPLOYMENT

	Apr 2020 - Present:	Associate Professor, Faculty of Marine Science and Technology, Fukui Prefectural University, Fukui, Japan.
	Apr 2012 - Mar 2020:	Assistant Professor, Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo, Tokyo, Japan.
	Apr 2010 - Mar 2012:	Postdoctoral Researcher, Atmosphere and Ocean Research Institute, The University of Tokyo, Kashiwa, Japan.
	Apr 2008 - Mar 2010:	Research Fellow of the Japan Society for the Promotion of Science, Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo, Tokyo, Japan.

RESEARCH INTEREST

My main research interests are in meso- and small-scale processes in the ocean interior spanning a broad area from the open ocean to coastal seas, especially their generation and dissipation mechanisms and impacts on large-scale ocean circulation. I am exploring these issues through a combination of theory, numerical simulations, and observations. Specific research topics include:

1. Turbulent mixing in the deep ocean
   • Dynamics of topographically trapped diurnal internal tides and associated bottom-intensified mixing in mid- to high-latitude regions such as the Kuril Straits connecting the Okhotsk Sea to the North Pacific Ocean
   • Theoretical formulation and global estimation of the energy conversion rate from subinertial surface tides to topographically trapped internal tides
   • Evaluation of the effects of diapycnal mixing on large-scale ocean circulation and global climate using ocean general circulation models and coupled climate models


2. Mesoscale features in strong ocean currents
   • Dynamics of the Kuroshio path variation south of Japan, especially the transition from the nonlarge meander path to the large meander path due to baroclinic instability enhanced over a local seamount
   • A general stability condition of a flow over bottom topography derived using the pseudoenergy conservation law and its application to the large meander path of the Kuroshio
   • Generation mechanism of tropical instability waves in the equatorial Pacific Ocean in terms of resonant Rossby wave coupling and their decay mechanism due to internal wave radiation

PUBLICATIONS (REFEREED ARTICLE)

• Tanaka, Y., 2023: Energy conversion rate from subinertial surface tides to internal tides, Journal of Physical Oceanography, 53, 1355-1374, https://doi.org/10.1175/JPO-D-22-0201.1. [link]
• Tanaka, Y., 2021: Stability of a flow over bottom topography: A general condition and a linear analysis in a two-layer quasi-geostrophic model with a possible application to a Kuroshio meander, Journal of Geophysical Research-Oceans, 126, e2021JC017849, https://doi.org/10.1029/2021JC017849. [link]
• Kawasaki, T., H. Hasumi, and Y. Tanaka, 2021: Role of tide-induced vertical mixing in the deep Pacific Ocean circulation, Journal of Oceanography, 77, 173–184, https://doi.org/10.1007/s10872-020-00584-0.
• Tanaka, Y., and T. Hibiya, 2019: Generation mechanism of tropical instability waves in the equatorial Pacific Ocean, Journal of Physical Oceanography, 49, 2901-2915, https://doi.org/10.1175/JPO-D-19-0094.1. [link]
• Yang, W., T. Hibiya, Y. Tanaka, L. Zhao, and H. Wei, 2019: Diagnostics and energetics of the topographic Rossby waves generated by a typhoon propagating over the ocean with a continental shelf slope, Journal of Oceanography, 75, 503-512, https://doi.org/10.1007/s10872-019-00518-5.
• Onuki, Y., and Y. Tanaka, 2019: Instabilities of finite-amplitude internal wave beams, Geophysical Research Letters, 46, 7527-7535, https://doi.org/10.1029/2019GL082570.
• Yang, W., T. Hibiya, Y. Tanaka, L. Zhao, and H. Wei, 2018: Modification of parametric subharmonic instability in the presence of background geostrophic currents, Geophysical Research Letters, 45, 12957-12962, https://doi.org/10.1029/2018GL080183.
• Tatebe, H., Y. Tanaka, Y. Komuro, and H. Hasumi, 2018: Impact of deep ocean mixing on the climatic mean state in the Southern Ocean, Scientific Reports, 8:14479, https://doi.org/10.1038/s41598-018-32768-6.
• Tanaka, Y., and T. Hibiya, 2017: Effects of Koshu Seamount on the development of baroclinic instability leading to the Kuroshio large meander, Journal of Physical Oceanography, 47, 2563-2576, https://doi.org/10.1175/JPO-D-17-0050.1. [link]
• Nishina, A., H. Nakamura, J.-H. Park, D. Hasegawa, Y. Tanaka, S. Seo, and T. Hibiya, 2016: Deep ventilation in the Okinawa Trough induced by Kerama Gap overflow, Journal of Geophysical Research-Oceans, 121, 6092-6102, https://doi.org/10.1002/2016JC011822.
• Tanaka, Y., T. Hibiya, and H. Sasaki, 2015: Downward lee wave radiation from tropical instability waves in the central equatorial Pacific Ocean: A possible energy pathway to turbulent mixing, Journal of Geophysical Research-Oceans, 120, 7137-7149, https://doi.org/10.1002/2015JC011017. [link]
• Yagi, M., I. Yasuda, T. Tanaka, Y. Tanaka, K. Ono, K. I. Ohshima, and K. Katsumata, 2014: Re-evaluation of turbulent mixing vertical structure in the Bussol' Strait and its impact on water-masses in the Okhotsk Sea and the North Pacific, Progress in Oceanography, 126, 121-134, https://doi.org/10.1016/j.pocean.2014.04.023.
• Itoh, S., Y. Tanaka, S. Osafune, I. Yasuda, M. Yagi, H. Kaneko, S. Konda, J. Nishioka, and Y. N. Volkov, 2014: Direct breaking of large-amplitude internal waves in the Urup Strait, Progress in Oceanography, 126, 109-120, https://doi.org/10.1016/j.pocean.2014.04.014.
• Tanaka, Y., I. Yasuda, S. Osafune, T. Tanaka, J. Nishioka, and Y. N. Volkov, 2014: Internal tides and turbulent mixing observed in the Bussol Strait, Progress in Oceanography, 126, 98-108, https://doi.org/10.1016/j.pocean.2014.04.009. [link]
• Tanaka, T., I. Yasuda, Y. Tanaka, and G. S. Carter, 2013: Numerical study on tidal mixing along the shelf break in the Green Belt in the southeastern Bering Sea, Journal of Geophysical Research-Oceans, 118, https://doi.org/10.1002/2013JC009113.
• Tanaka, Y., I. Yasuda, H. Hasumi, H. Tatebe, and S. Osafune, 2012: Effects of the 18.6-year modulation of tidal mixing on the North Pacific bidecadal climate variability in a coupled climate model, Journal of Climate, 25, 7625-7642, https://doi.org/10.1175/JCLI-D-12-00051.1. [link]
• Tanaka, Y., T. Hibiya, and Y. Niwa, 2010b: Assessment of the effects of tidal mixing in the Kuril Straits on the formation of the North Pacific Intermediate Water, Journal of Physical Oceanography, 40, 2569-2574, https://doi.org/10.1175/2010JPO4506.1. [link]
• Tanaka, Y., T. Hibiya, Y. Niwa, and N. Iwamae, 2010a: Numerical study of K1 internal tides in the Kuril straits, Journal of Geophysical Research-Oceans, 115, C09016, https://doi.org/10.1029/2009JC005903. [link]
• Tanaka, Y., T. Hibiya, and Y. Niwa, 2007: Estimates of tidal energy dissipation and diapycnal diffusivity in the Kuril Straits using TOPEX/POSEIDON altimeter data, Journal of Geophysical Research-Oceans, 112, C10021, https://doi.org/10.1029/2007JC004172. [link]
• Nagasawa, M., T. Hibiya, K. Yokota, Y. Tanaka, and S. Takagi, 2007: Microstructure measurements in the mid-depth waters of the North Pacific, Geophysical Research Letters, 34, L05608, https://doi.org/10.1029/2006GL028695 (AGU Journal Highlight).

PRESENTATIONS

• Tanaka, Y.: Generation of superinertial internal tides propagating along the coast: the role of topographic modes in the formation of topographically modified internal Kelvin waves, Ocean Sciences Meeting 2024, New Orleans, USA, February 2024 (poster).
• Tanaka, Y.: A stability condition of a topographically constrained geostrophic current and its application to the large meander path of the Kuroshio, Asia Oceania Geosciences Society (AOGS) 20th Annual Meeting, Singapore, August 2023 (poster).
• Tanaka, Y.: Energy conversion rate from subinertial surface tides to internal tides, Asia Oceania Geosciences Society (AOGS) 20th Annual Meeting, Singapore, July 2023.
• Hibiya, T., Y. Tanaka, and Y. Hirano: Revisiting tide-induced near-field mixing in the abyssal ocean, 28th International Union of Geodesy and Geophysics (IUGG) General Assembly, Berlin, Germany, July 2023.
• Tanaka, Y.: Energy conversion rate from subinertial surface tides to internal tides, 28th International Union of Geodesy and Geophysics (IUGG) General Assembly, Berlin, Germany, July 2023.
• Tanaka, Y.: Stability of a flow over bottom topography: A linear stability analysis and a numerical simulation in a two-layer quasi-geostrophic model, Japan Geoscience Union Meeting 2022, Hybrid (Online and On-site at Chiba, Japan), May-June 2022 (poster).
• Tanaka, Y.: Stability condition of a flow constrained by topography and its application to the large meander path of the Kuroshio, Japan Geoscience Union Meeting 2022, Hybrid (Online and On-site at Chiba, Japan), May-June 2022 (poster).
• Yang, W., H. Wei, L. Zhao, T. Hibiya, and Y. Tanaka: Two steps in the energy transfer from M2 internal tides to high-frequency internal waves, Japan Geoscience Union Meeting 2022, Hybrid (Online and On-site at Chiba, Japan), May 2022.
• Tanaka, Y.: Stability of a flow over bottom topography: a general condition and a linear analysis in a two-layer quasi-geostrophic model with a possible application to a Kuroshio meander, Ocean Sciences Meeting 2022, Virtual Meeting, March 2022.
• Tanaka, Y.: Symmetric and mixed layer instability at a sharp ocean front, Japan Geoscience Union-American Geophysical Union Joint Meeting 2020, Virtual Meeting, July 2020.
• Onuki, Y., and Y. Tanaka: Instabilities of finite-amplitude internal wave beams, Ocean Sciences Meeting 2020, San Diego, USA, February 2020.
• Tatebe, H., T. Kawasaki, Y. Tanaka, I. Yasuda, and H. Hasumi: Numerical reevaluation of the tide-induced 18.6-year climate variability over the Pacific using a climate model with an eddy-permitting OGCM, Ocean Sciences Meeting 2020, San Diego, USA, February 2020 (poster).
• Tanaka, Y., and T. Hibiya: Generation mechanism of tropical instability waves in the equatorial Pacific Ocean, First International Conference on Ocean Fronts and Eddies (ICOFE-1), Zhoushan, China, October 2019.
• Tanaka, Y., and T. Hibiya: Effects of Koshu Seamount on the development of baroclinic instability leading to the Kuroshio large meander, First International Conference on Ocean Fronts and Eddies (ICOFE-1), Zhoushan, China, October 2019.
• Tanaka, Y., and T. Hibiya: Generation mechanism of tropical instability waves in the equatorial Pacific Ocean, 27th International Union of Geodesy and Geophysics (IUGG) General Assembly, Montreal, Canada, July, 2019 (poster).
• Onuki, Y., and Y. Tanaka: Instabilities of finite-amplitude internal wave beams, Japan Geoscience Union Meeting 2019, Chiba, Japan, May 2019.
• Tanaka, Y., and T. Hibiya: Baroclinic instability over Koshu Seamount leading to the Kuroshio large meander, 2018 Ocean Sciences Meeting, Portland, USA, February 2018 (poster).
• Fukuzawa, K., Y. Tanaka, and T. Hibiya: The amplification mechanism of a meteo-tsunami originating off the western coast of Kyushu Island of Japan in the winter of 2004, 2018 Ocean Sciences Meeting, Portland, USA, February 2018.
• Tanaka, Y., and T. Hibiya: Effects of Koshu Seamount on the development of baroclinic instability leading to the Kuroshio large meander, Asia Oceania Geosciences Society (AOGS) 14th Annual Meeting, Singapore, August 2017.
• Tanaka, Y., and T. Hibiya: Downward lee wave radiation from tropical instability waves in the central equatorial Pacific Ocean: a possible energy pathway to turbulent mixing, International Symposium "Ocean Mixing Processes: Impact on Biogeochemistry, Climate and Ecosystem", Tokyo, Japan, March 2017 (poster).
• Tanaka, Y., T. Hibiya, and H. Sasaki: Downward lee wave radiation from Pacific tropical instability waves: a possible energy pathway to turbulent mixing, Japan Geoscience Union Meeting 2016, Chiba, Japan, May 2016.
• Takahashi, A., T. Hibiya, and Y. Tanaka: Dissipation processes of internal waves generated by geostrophic flows impinging on bottom topography, Japan Geoscience Union Meeting 2016, Chiba, Japan, May 2016.
• Tanaka, Y., T. Hibiya, and H. Sasaki: Downward lee wave radiation from tropical instability waves in the central equatorial Pacific Ocean: a possible energy pathway to turbulent mixing, 2016 Ocean Sciences Meeting, New Orleans, USA, February 2016 (poster).
• Tanaka, Y., T. Hibiya, and H. Sasaki: Downward “lee wave” radiation from tropical instability waves in the central equatorial Pacific: a possible energy pathway to turbulent mixing, 26th International Union of Geodesy and Geophysics (IUGG) General Assembly, Prague, Czech Republic, July 2015.
• Itoh, S., Y. Tanaka, S. Osafune, I. Yasuda, and M. Yagi: Direct breaking of large-amplitude internal waves in the Urup Strait, Kuril Islands, 2014 Ocean Sciences Meeting, Honolulu, USA, February 2014 (poster).
• Yasuda, I., Y. Tanaka, S. Itoh, H. Hasumi, and S. Osafune: Observation and modeling of turbulent mixing in the Kuril Straits and impact of its 18.6-year period tidal cycle on ocean and climate, 2014 Ocean Sciences Meeting, Honolulu, USA, February 2014.
• Tanaka, Y., T. Hibiya, and H. Sasaki: Global estimates of internal wave energy flux radiating from geostrophic flows based on a high-resolution numerical model, 2014 Ocean Sciences Meeting, Honolulu, USA, February 2014 (poster).
• Yasuda, I., Y. Tanaka, S. Itoh, H. Hasumi, S. Osafune, T. Tanaka, M. Yagi, and H. Tatebe: Observation and modelling of turbulent mixing in the Kuril Straits and impact of its 18.6-year period tidal cycle on ocean and climate, IAHS/IAPSO/IASPEI Joint Assembly, Gothenburg, Sweden, July 2013.
• Tanaka, T., I. Yasuda, and Y. Tanaka: Numerical study on tidal mixing along the shelf break in the southeastern Bering Sea, Asia Oceania Geosciences Society (AOGS) 10th Annual Meeting, Brisbane, Australia, June 2013 (poster).
• Tanaka, Y., I. Yasuda, S. Osafune, T. Tanaka, J. Nishioka, and Y. N. Volkov: Internal Tides and Turbulent Mixing Observed in the Bussol Strait, Asia Oceania Geosciences Society (AOGS) 10th Annual Meeting, Brisbane, Australia, June 2013.
• Yasuda, I., Y. Tanaka, S. Itoh, H. Hasumi, K. Komatsu, S. Osafune, M. Yagi, T. Tanaka, H. Kaneko, T. Ikeya, S. Konda, J. Nishioka, T. Nakatsuka, K. Katsumata, H. Tatebe, Y. Watanabe, Y. Hiroe, and T. Nakamura: Observation and modelling of turbulent mixing in the Kuril and Aleutian Straits and impact of its 18.6-year period tidal cycle on ocean and climate, 2012 AGU Fall Meeting, San Francisco, USA, December 2012 (poster).
• Tanaka, Y., I. Yasuda, H. Hasumi, H. Tatebe, and S. Osafune: Effects of the 18.6-year modulation of tidal mixing on bidecadal climate variability in the North Pacific, 2012 Ocean Sciences Meeting, Salt Lake City, USA, February 2012.
• Tanaka, Y., T. Hibiya, and Y. Niwa: Assessment of the effects of tidal mixing in the Kuril Straits on the formation of the North Pacific Intermediate Water, 25th International Union of Geodesy and Geophysics (IUGG) General Assembly, Melbourne, Australia, June 2011.
• Tanaka, Y., T. Hibiya, Y. Niwa, and N. Iwamae: Numerical study of K1 internal tides in the Kuril Straits, 2010 Ocean Sciences Meeting, Portland, USA, February 2010.
• Tanaka, Y., T. Hibiya, and Y. Niwa: Estimates of tidal energy dissipation and diapycnal diffusivity in the Kuril Straits using TOPEX/POSEIDON altimeter data, Japan-Korea Joint Seminar on Physical Process in the Ocean and its Parameterization, Tokyo, Japan, December 2007.
• Tanaka, Y., T. Hibiya, and Y. Niwa: Estimates of tidal energy dissipation and diapycnal diffusivity in the Kuril Straits using TOPEX/Poseidon altimeter data, 24th International Union of Geodesy and Geophysics (IUGG) General Assembly, Perugia, Italy, July 2007.
• Hibiya, T., M. Nagasawa, K. Yokota, Y. Tanaka, T. Tanno, and S. Takagi: Identification of mixing hotspots in the world ocean, 2006 Ocean Sciences Meeting, Honolulu, USA, February 2006.