Related Experiment Video
Updated: Jun 3, 2026
04:35
Preparation of Free-Surface Hyperbolic Water Vortices
Published on: July 28, 2023
Enhanced turbulence and energy dissipation at ocean fronts
Eric D'Asaro1, Craig Lee, Luc Rainville
1Applied Physics Laboratory and School of Oceanography, University of Washington, Seattle, WA 98105-6698, USA. dasaro@apl.washington.edu
Science (New York, N.Y.)
|March 12, 2011
Summary
Ocean fronts can significantly energize turbulence in the ocean surface boundary layer, challenging the traditional view of atmospheric forcing as the sole driver. This discovery impacts climate models and our understanding of air-sea exchange.
Area of Science:
- Oceanography
- Fluid Dynamics
- Climate Science
Background:
- The ocean surface boundary layer (OSBL) is crucial for air-sea exchange.
- Traditionally, atmospheric forcing is considered the primary driver of OSBL turbulence.
- Current climate models rely on this paradigm.
Purpose of the Study:
- To investigate the energy sources driving turbulence in the OSBL.
- To challenge the classical paradigm of atmospheric forcing as the sole driver.
- To quantify the role of ocean fronts in OSBL turbulence.
Main Methods:
- In-situ observations at a 1-kilometer-wide front in the Kuroshio Current.
- Measurement of energy dissipation rates within the OSBL.
- Quantitative analysis of wind-frontal velocity interactions.
Main Results:
- Observed energy dissipation rates enhanced by one to two orders of magnitude.
- Evidence suggests ocean fronts, not atmospheric forcing, supplied energy for turbulence.
- Winds aligned with frontal velocity catalyzed energy release from the front to turbulence.
- The resulting boundary layer is stratified, unlike the classically well-mixed layer.
Conclusions:
- Ocean fronts can be a dominant energy source for OSBL turbulence.
- This finding necessitates revisions to climate models and air-sea exchange parameterizations.
- Intense fronts in major currents (Kuroshio, Gulf Stream, ACC) have significant climate implications.
More Related Videos
Related Concept Videos
01:24Turbulent Flow
Turbulent flow is characterized by unpredictable fluctuations in velocity and pressure, which result in a chaotic fluid movement distinct from the orderly patterns of laminar flow. While laminar flow is governed by smooth, parallel layers with minimal mixing, turbulent flow exhibits highly irregular, three-dimensional patterns. This behavior arises due to instabilities in the fluid's velocity profile, and amplifies as the flow velocity increases. Minor disturbances, known as turbulent spots,...
01:18Boundary Layer Characteristics
When a fluid encounters a solid surface, a boundary layer forms due to the interaction between the fluid's motion and the stationary surface. This phenomenon is characterized by a thin region adjacent to the surface where viscous forces dominate, influencing the fluid's velocity profile. The development of the boundary layer begins at the leading edge of the surface and evolves as the fluid moves downstream.As the fluid flows over the surface, friction between the fluid and the wall slows down...
01:27Laminar Flow
Laminar flow represents a smooth, orderly fluid motion where particles move along parallel paths, resulting in minimal mixing between layers. Streamlined particle paths characterize this flow regime and occur under conditions where viscous forces dominate over inertial forces. The distinction between laminar, transitional, and turbulent flow is primarily determined by the Reynolds number, a dimensionless quantity calculated as:
01:07Damped Oscillations
In the real world, oscillations seldom follow true simple harmonic motion. A system that continues its motion indefinitely without losing its amplitude is termed undamped. However, friction of some sort usually dampens the motion, so it fades away or needs more force to continue. For example, a guitar string stops oscillating a few seconds after being plucked. Similarly, one must continually push a swing to keep a child swinging on a playground.
Although friction and other non-conservative...
Although friction and other non-conservative...
01:27Energy Considerations in Open Channel Flow
Open channel flow, where a fluid flows with a free surface exposed to the atmosphere, is primarily governed by gravitational and surface effects, distinguishing it from closed conduit or pipe flow. In open channels such as rivers, canals, and artificial channels, energy analysis provides valuable insights into flow behavior and the relationship between depth, velocity, and slope.Specific Energy and Flow DepthIn open channel flow, the specific energy, E, combines the gravitational potential...
01:26General External Flow Characteristics
The study of external flow is essential for creating structures and objects that interact efficiently and safely with moving fluids, such as air or water. When a body is immersed in a flowing fluid, it experiences two primary forces: drag, which opposes motion along the flow direction, and lift, which acts perpendicular to the flow. The shape, size, and orientation of the object influence these forces.Streamlined and Blunt Bodies in External FlowObjects in fluid flow are classified as...