Mixing characteristics of the subarctic front in the Kuroshio-Oyashio confluence region

• Autorzy: Zhu Ke-Lan , Chen Xi , Mao Ke-Feng , Hu Dong , Hong Sen , Li Yan

Identyfikatory

DOI

10.1016/j.oceano.2018.07.004

• Języki publikacji: EN

Abstrakty

EN

This paper analyzes the mixing characteristics of the Subarctic Front (SAF) in the Kuroshio-Oyashio Confluence Region based on temperature, salinity, and current data obtained from surveys and remote sensing in June 2016. The frontal zone of the observed area is at 145°-151°E, 38°-41°N. The front is distributed between 25.5-26.7 σ₀ in a band pattern inclined from north to south and is deeper in the south. The region shallower than 200 m and distributed along the isopycnal of 25.9-26.1σ₀ has thestrongest horizontal temperature andsalinity gradients, andthe largest of the former can reach over 0.7°C/km. Diapycnal mixing of the SAF ismainly turbulent; it is stronger in the north than in the south. The region with stronger turbulence (K_ρ > 10^-3.5 m²/s) is distributed mainly in water layers within and under the front (26.1-26.7σ₀), showing that the SAF is shallower in the north and deeper in the south along the front. Symmetric instability may be the main factor causing strong turbulent mixing in the frontal zone.Double diffusion mixing is stronger in the south than in the north; the region with stronger double diffusion (K₀ > 10^-4.5 m²/s) is distributed mainly in water layers within and above the front (25-26.5σ₀) on the southern side of the SAF. These water layers are dominated mainly by „salt-fingering'' double diffusion, with only a few water layers dominated by „diffusive layering'' double diffusion mixing in middle and lower waters deeper than 300 m.

Słowa kluczowe

EN

Kuroshio-Oyashio; confluence region; subarctic front; mixing; turbulent eddy diffusivity; thermal diffusivity

• Wydawca: Polish Academy of Sciences, Institute of Oceanology ; Elsevier
• Czasopismo: Oceanologia
• Rocznik: 2019
• Tom: No. 61 (1)
• Strony: 103--113
• Opis fizyczny: Bibliogr. 47 poz., tab., wykr.

Twórcy

autor

Zhu Ke-Lan

• Army of PLA, Beijing, China

autor

Chen Xi

• College of Meteorology and Oceanography, National University of Defense Technology, Nanjing, China

autor

Mao Ke-Feng

• College of Meteorology and Oceanography, National University of Defense Technology, Nanjing, China

autor

Hu Dong

• Army of PLA, Beijing, China

autor

Hong Sen

• Army of PLA, Beihai, China

autor

Li Yan

• College of Meteorology and Oceanography, National University of Defense Technology, Nanjing, China

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Uwagi

Opracowanie rekordu w ramach umowy 509/P-DUN/2018 ze środków MNiSW przeznaczonych na działalność upowszechniającą naukę (2019).