Langmuir turbulence is a complex turbulent process in the ocean upper mixed layer. The Coriolis parameter has an important effect on Langmuir turbulence through the Coriolis-Stokes force and Ekman effect, however, this effect on Langmuir turbulence has not been systematically investigated. Here, the impact of the Coriolis parameter on Langmuir turbulence with a change of latitude (LAT) from 20°N to 80°N is studied using a non-hydrostatic large eddy simulation model under an ideal condition. The results show that the ratio of the upper mixed layer depth to Ekman depth scale (RME) RME = 0.266 (LAT = 50°N) is a key value (latitude) for the modulation effect of the Coriolis parameter on the mean and turbulent statistics of Langmuir turbulence. It is found that the rate of change of the sea surface temperature, upper mixed layer depth, entrainment flux, crosswind velocity, downwind vertical momentum flux, and turbulent kinetic energy budget terms associated with Langmuir turbulence are more evident at RME ⩽ 0.266 (LAT ⩽ 50°N) than at RME ⩾ 0.266 (LAT ⩾ 50°N). However, the rate of change of the depth-averaged crosswind vertical momentum flux does not have a clear variation between RME ⩽ 0.266 and RME ⩾ 0.266. The complex changes of both Langmuir turbulence characteristics and influence of Langmuir turbulence on the upper mixed layer with latitude presented here may provide more information for further improving Langmuir turbulence parameterization.
Bibliographical noteFunding Information:
The research of Guojing LI, Dongxiao WANG, and Yeqiang SHU was supported by the National Key Research and Development Program of China (Grant No. 2018YFC1405701), the National Natural Science Foundation of China (Grant Nos. 92158204, 41506001, 42076019, 42076026 and 41876017), and the Project supported by Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou) (Grant No. GML2019ZD0304). Lian SHEN acknowledges the support by University of Minnesota. The large eddy simulation model is provided by National Center for Atmospheric Research. All numerical calculations were carried out at the High Performance Computing Center (HPCC) of the South China Sea Institute of Oceanology, Chinese Academy of Sciences.
© 2022, Institute of Atmospheric Physics/Chinese Academy of Sciences, and Science Press and Springer-Verlag GmbH Germany, part of Springer Nature.
- Coriolis parameter
- Langmuir turbulence
- large eddy simulation
- the upper mixed layer