Yasumasa Miyazawa

Japan Agency for Marine-Earth Science and Technology

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Sergey M. Varlamov

Japan Agency for Marine-Earth Science and Technology

Xinyu Guo

Ehime University

Toru Miyama

Japan Agency for Marine-Earth Science and Technology

Takuji Waseda

The University of Tokyo

Tsutomu Hihara

Japan Fisheries Research and Education Agency

Yusuke Uchiyama

Kobe University

Hidenori Aiki

Nagoya University

Yu-Lin K. Chang

Japan Agency for Marine-Earth Science and Technology

Hitoshi Tamura

Port and Airport Research Institute

Misako Kachi

Japan Aerospace Exploration Agency

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Japan Agency for Marine-Earth Science and Technology

106

The University of Tokyo

Hokkaido University

Kyoto University

Kyushu University

Centre National de la Recherche Scientifique

Japan Fisheries Research and Education Agency

Tohoku University

Japan Meteorological Agency

Meteorological Research Institute

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Assimilation of high-resolution sea surface temperature data into an operational nowcast/forecast system around Japan using a multi-scale three-dimensional variational scheme

Ocean Dynamics (2017)

Yasumasa Miyazawa Sergey M. Varlamov Toru Miyama Xinyu Guo Tsutomu Hihara

A multi-scale three-dimensional variational (MS-3DVAR) scheme is developed to assimilate high-resolution Himawari-8 sea surface temperature (SST) data for the first time into an operational ocean nowcast/forecast system targeting the North Western Pacific, JCOPE2. MS-3DVAR improves representation of the Kuroshio path south of Japan, its associated sea level variations, and temperature/salinity profiles south of Japan, the Kuroshio/Oyashio mixed water region, and the Japan Sea as compared to those of the products by the traditional single-scale 3DVAR. Validation results demonstrate that MS-3DVAR well assimilates the sparsely distributed in situ temperature and salinity profiles data by spreading the information over the large scale and by representing the detailed information near the measurement points. MS-3DVAR succeeds to assimilate the Himawari-8 SST product without noisy features caused by the cloud effects. We also find that MS-3DVAR is more effective for estimating oceanic conditions in regions with smaller mesoscale variability including the mixed water region and Japan Sea than in south of Japan.

Temperature salinity diagrams

10.1007/s10236-017-1056-1

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Citations (93)

Changes in the Kuroshio path, surface velocity and transport during the last 35,000 years

Zenodo (CERN European Organization for Nuclear Research) (2021)

Haiyan Yang Xinyu Guo Yasumasa Miyazawa M. Varlamov Sergey Abe‐Ouchi Ayako

The major data for “Changes in the Kuroshio path, surface velocity and transport during the last 35,000 years” are listed as follows: 1) The annual mean surface current (0-100m, m/s) in 5 cases. Data are separately saved in MATLAB files (surface_velocity_0ka.mat, surface_velocity_6ka.mat, surface_velocity_lgm.mat, surface_velocity_30ka.mat and surface_velocity_35ka.mat) with variables of longitude, latitude, u and v. 2) The Kuroshio paths (longitude and latitude) in 5 cases are saved in MATLAB file of “data_pathxy.mat”. 3) Distributions of upper 1000-m integrated volume-transport stream function from model results in 5 cases. Data is saved in the MATLAB file of “VT_model.mat” with variables of longitude, latitude, VT_model and casename. 3) Distributions of wind-driven Sverdrup transport stream function calculated by wind stresses in 5 cases. Data is saved in the MATLAB file of “ST_wind.mat” with variables of longitude, latitude, ST_wind and casename.

10.5281/zenodo.5733861

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Changes in the Kuroshio path, surface velocity and transport during the last 35,000 years

Zenodo (CERN European Organization for Nuclear Research) (2021)

Haiyan Yang Xinyu Guo Yasumasa Miyazawa M. Varlamov Sergey Abe‐Ouchi Ayako

10.5281/zenodo.5733860

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MESOSCALE REPRODUCIBILITY IN AN ASSIMILATIVE OCEANIC DOWNSCALING MODEL USING A 3-D STRATIFICATION ESTIMATE BASED ON SATELLITE ALTIMETRY AND ARGO FLOAT DATA

Journal of Japan Society of Civil Engineers Ser B3 (Ocean Engineering) (2015)

Yusuke Uchiyama Ryosuke Kanki Akiko Takano Hidekatsu Yamazaki Yasumasa Miyazawa

海面高度計およびArgoフロートデータを用いて3次元海洋密度場を推定し，TS（水温・塩分）nudgingと呼ばれる簡易的な4次元データ同化を組み込んだ領域海洋循環モデルROMSを用いて，日本沿岸の黒潮流域における海洋構造の再現性について検討した．水平・鉛直密度構造，メソスケール変動強度，黒潮流路および強度などに関する詳細な比較を行い，本手法の高い再現性を示した．この密度推定法は原理的にほぼ全球に適用可能であり，公開されているデータのみを用いるので新たなコストを必要としないため，一般性・汎用性が極めて高い．JCOPE2に代表される高品質な海洋再解析データが存在しないような海域に対しても適用可能であり，ダウンスケーリング海洋モデリングに広く用いることが可能である．

Argo

Satellite Altimetry

Stratification (seeds)

Float (project management)

10.2208/jscejoe.71.i_365

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Journal of Oceanography (2000)

Yasumasa Miyazawa Shinya Minato

Typhoon

Stratification (seeds)

Inflow