A non-breaking-wave-generated turbulence mixing scheme for a global ocean general circulation model

• Published in: Ocean dynamics 2020-03, Vol.70 (3), p.293-305
• Main Authors: Zhuang, Zhanpeng, Zheng, Quanan, Yuan, Yeli, Yang, Guangbing, Zhao, Xinhua
• Format: Article
• Language: English
• Subjects: Atmospheric Sciences; Breaking waves; Coefficients; Computer simulation; Earth and Environmental Science; Earth Sciences; Energy dissipation; Energy exchange; Fluid- and Aerodynamics; General circulation models; Geophysics/Geodesy; Hemispheres; Kinetic energy; Kinetic energy dissipation; Marine sciences; Mixed layer; Mixed layer depth; Monitoring/Environmental Analysis; Ocean circulation; Ocean currents; Ocean models; Ocean temperature; Ocean temperature structure; Oceanography; Oceans; Significant wave height; Surface water waves; Surface waves; Temperature structure; Turbulence; Upper ocean; Vertical mixing; Water circulation; Wave frequency; Wave height; Wave number; Wavelengths
• ISSN: 1616-7341; 1616-7228
• DOI: 10.1007/s10236-019-01338-3

A novel vertical mixing scheme to describe the influence of the non-breaking surface waves in ocean general circulation models is proposed based on the second-order turbulence closure model and a mathematical relationship fitted between the in situ observations of the turbulence kinetic energy dissipation rate and the calculated velocity shear module of non-breaking surface waves. The non-breaking-wave-generated turbulence mixing coefficients can be calculated empirically in terms of the wave spectral parameters including Φ SW , K , and ω , where Φ SW is the wave number spectrum of the significant wave height, K is the wave number, ω is the surface wave frequency. The effect of the new mixing scheme on global ocean circulation simulation was tested using the MArine Science and NUmerical Modeling ocean model. The results indicate significant improvement in the upper-ocean temperature structure and the mixed layer depth, i.e., the non-breaking-wave-generated turbulence mixing plays an important role in the upper ocean at high latitudes in summer for both hemispheres compared with traditional Mellor-Yamada 2.5 scheme.