Submesoscales are a significant turbulence source in global ocean surface boundary layer.
Jihai Dong1,2, Baylor Fox-Kemper3, Jacob O Wenegrat4
1School of Marine Sciences, Nanjing University of Information Science and Technology, Nanjing, China. jihai_dong@nuist.edu.cn.
Nature Communications
|November 5, 2024
Summary
Submesoscale ocean fronts significantly contribute to turbulent kinetic energy in the ocean boundary layer, challenging traditional views. This finding impacts climate models and our understanding of ocean energy and carbon cycles.
Area of Science:
- * Oceanography
- * Climate Science
- * Fluid Dynamics
Background:
- * The ocean surface boundary layer is crucial for climate, influencing energy and carbon cycles.
- * Accurate climate models depend on understanding ocean turbulence.
- * Traditional turbulence sources include waves, winds, and convection.
Purpose of the Study:
- * To investigate the role of submesoscale phenomena at ocean fronts as a source of turbulent energy.
- * To quantify the contribution of submesoscale geostrophic shear production to the ocean boundary layer's turbulent kinetic energy budget.
Main Methods:
- * Application of a non-dimensional turbulent kinetic energy budget equation.
- * Analysis of turbulence within the ocean boundary layer, focusing on submesoscale fronts.
Main Results:
- * Submesoscale geostrophic shear at ocean fronts is a significant source of turbulent energy, particularly away from the sea surface.
- * This contribution can account for up to 34% of total dissipation in winter and 17% in summer at mid-depth.
- * The energy contribution is significant despite being intermittent in space and time.
Conclusions:
- * Previous understanding of ocean boundary layer turbulence is fundamentally deficient.
- * Submesoscale processes at fronts must be considered in climate models.
- * Reappraisal of observational scales, model resolution, and parameterizations is needed.
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