Ocean waves crashing with swirling energy patterns beneath the surface

Ocean Mixing Unveiled: How Waves and Turbulence Shape Our Seas

Kai Mendoza in Climate & Environment December 2025 • 4 min read.

"New research sheds light on the complex interaction of waves and turbulence in the ocean mixed layer, offering critical insights for climate modeling and marine ecosystems."

The ocean is a dynamic environment where energy is constantly exchanged between the atmosphere and the water. This exchange is largely governed by turbulence, which mixes water, distributes heat, and influences marine life. Understanding how turbulence behaves in the ocean mixed layer (OML) is crucial for accurate climate modeling and predicting the health of our oceans.

Turbulence in the OML is a complex interplay of energy production, buoyancy (the tendency of an object to float), and dissipation (the conversion of kinetic energy into heat). Large-scale numerical models rely on accurate parameterizations of these processes, especially dissipation, to compensate for their inability to directly simulate turbulence at the smallest scales.

Recent research has focused on refining our understanding of how energy dissipates in the OML. Unlike the atmospheric boundary layer (ABL), the OML is significantly influenced by surface gravity waves and Langmuir circulations, creating more complex patterns of dissipation. This article delves into a groundbreaking study that examines these processes, providing new insights into wave-turbulence scaling in the ocean.

What Drives Turbulence in the Ocean's Surface?

Ocean waves crashing with swirling energy patterns beneath the surface

Traditionally, scientists have approached turbulence in the OML using similarity scaling, which treats the OML as a shear-driven wall layer. This approach assumes a constant stress with a logarithmic velocity profile, where shear (the change in velocity with depth) is proportional to the friction velocity (a measure of wind stress) and inversely proportional to depth.

However, observations have revealed that this simple model often falls short, particularly in the near-surface region. Many studies have reported significantly higher rates of turbulent kinetic energy dissipation than predicted by the shear-driven wall layer model. This discrepancy is attributed to the presence of breaking surface gravity waves, which directly inject turbulent kinetic energy into the near-surface region.

Breaking Waves: Introduce significant turbulence near the surface.
Langmuir Circulations: Enhance mixing and dissipation.
Wind Forcing: Creates shear and contributes to turbulence production.

One proposed scaling suggests that enhanced dissipation rates can be linked to parameters of the wind-wave field. The uppermost region of the ocean, down to a depth of about 60% of the significant wave height, experiences a uniform turbulent dissipation rate due to breaking waves. Below this, an intermediate region exhibits a dissipation rate that decays with depth. Further down, dissipation follows the traditional shear-driven wall layer scaling.

The Future of Ocean Turbulence Research

While significant progress has been made, accurately parameterizing turbulence in the OML remains a challenge. The intermittent nature of turbulence and the scarcity of comprehensive datasets, particularly in the open ocean, limit the ability to validate and refine existing models. Future research needs to focus on collecting more high-quality data under diverse sea states and conditions to better understand the complex interplay of factors that govern turbulence in the ocean's surface.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.5194/os-9-597-2013, Alternate LINK

Title: Wave-Turbulence Scaling In The Ocean Mixed Layer

Subject: Cell Biology

Journal: Ocean Science

Publisher: Copernicus GmbH

Authors: G. Sutherland, B. Ward, K. H. Christensen

Published: 2013-07-08

Everything You Need To Know

What is the Ocean Mixed Layer (OML), and why is it important?

The term, Ocean Mixed Layer (OML), refers to the uppermost part of the ocean where the water is relatively well-mixed due to turbulence. This layer is where the atmosphere and the ocean interact, with energy being exchanged. Its significance lies in its direct influence on climate models, as the OML's properties (temperature, salinity, and the distribution of heat) greatly affect global climate patterns. The behavior within the OML also impacts marine ecosystems by determining nutrient availability and the distribution of marine life.

What are the main drivers of turbulence in the ocean's surface?

Turbulence in the Ocean Mixed Layer (OML) is driven by several factors. Breaking Waves directly inject turbulent kinetic energy into the near-surface region. Langmuir Circulations enhance mixing and dissipation. Additionally, Wind Forcing creates shear and contributes to turbulence production. These forces work together to create a complex interplay, making the OML a dynamic environment.

How does the behavior of turbulence in the Ocean Mixed Layer (OML) differ from that in the atmospheric boundary layer (ABL)?

The primary difference lies in the models used to describe them. The traditional approach uses shear-driven wall layer scaling, which is based on constant stress and a logarithmic velocity profile. However, observations have revealed that this model often underestimates the rates of turbulent kinetic energy dissipation, especially near the surface. Enhanced dissipation rates in the Ocean Mixed Layer (OML) can be linked to parameters of the wind-wave field. The presence of Breaking Waves and Langmuir Circulations in the OML, which are not as significant in the atmospheric boundary layer (ABL), creates more complex patterns of dissipation.

Why is understanding turbulence in the Ocean Mixed Layer (OML) so important?

The implications of understanding turbulence in the Ocean Mixed Layer (OML) are far-reaching. Accurate climate models are dependent on understanding heat distribution within the OML. Improving these models allows for better predictions of climate change, including sea surface temperatures, which influence weather patterns globally. Moreover, the OML's properties influence marine ecosystems. The mixing and distribution of nutrients, driven by turbulence, directly impact marine life.

What is the future of ocean turbulence research?

Future research on Ocean Turbulence will focus on gathering more comprehensive and high-quality datasets to validate and refine existing models. This includes collecting data under diverse sea states and conditions to better understand the complex interplay of factors that govern turbulence in the ocean's surface. Improving parameterizations of these processes will lead to more accurate climate predictions and a better understanding of marine ecosystems.