Related Experiment Video
Updated: Jul 5, 2026
07:28
Evolution of Staircase Structures in Diffusive Convection
Published on: September 5, 2018
A stochastic dynamical systems view of the Atlantic Multidecadal Oscillation
H A Dijkstra1, L M Frankcombe, A S von der Heydt
1Institute for Marine and Atmospheric Research Utrecht, Department of Physics and Astronomy, Utrecht University, 3508 TC Utrecht, The Netherlands. dijkstra@phys.uu.nl
Summary
We present a dynamical systems framework for the Atlantic Multidecadal Oscillation (AMO), finding similarities with El Niño/Southern Oscillation dynamics. A stochastic Hopf bifurcation likely drives North Atlantic sea surface temperature variability.
Area of Science:
- Climate Dynamics
- Oceanography
- Dynamical Systems Theory
Background:
- The Atlantic Multidecadal Oscillation (AMO) significantly influences North Atlantic climate and sea surface temperatures.
- Understanding the underlying mechanisms of the AMO is crucial for climate prediction.
Purpose of the Study:
- To develop a dynamical systems framework for the AMO.
- To investigate the similarities between AMO and El Niño/Southern Oscillation (ENSO) dynamics.
- To identify the specific mechanisms driving multidecadal variability in the North Atlantic.
Main Methods:
- Utilized a minimal primitive equation model to simulate Atlantic Ocean circulation.
- Applied dynamical systems theory, including Hopf bifurcation analysis.
- Incorporated stochastic processes to model noise effects on sea surface temperature variability.
Main Results:
- Identified a normal mode of multidecadal variability within the minimal model.
- This mode can destabilize the background climate state via a Hopf bifurcation.
- Noise was found to determine the amplitude of associated sea surface temperature variability.
Conclusions:
- The study supports the involvement of a stochastic Hopf bifurcation in generating observed North Atlantic multidecadal variability.
- The dynamical systems framework offers insights into AMO mechanisms, drawing parallels with ENSO.
- This research contributes to a deeper understanding of climate variability in the North Atlantic region.
Related Concept Videos
01:04Oscillations about an Equilibrium Position
Stability is an important concept in oscillation. If an equilibrium point is stable, a slight disturbance of an object that is initially at the stable equilibrium point will cause the object to oscillate around that point. For an unstable equilibrium point, if the object is disturbed slightly, it will not return to the equilibrium point. There are three conditions for equilibrium points—stable, unstable, and half-stable. A half-stable equilibrium point is also unstable, but is named so because...
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...
01:20Types of Damping
If the amount of damping in a system is gradually increased, the period and frequency start to become affected because damping opposes, and hence slows, the back and forth motion (the net force is smaller in both directions). If there is a very large amount of damping, the system does not even oscillate; instead, it slowly moves toward equilibrium. In brief, an overdamped system moves slowly towards equilibrium, whereas an underdamped system moves quickly to equilibrium but will oscillate about...
01:19Cyclic Processes And Isolated Systems
A thermodynamic system with zero heat exchange and work is an isolated system. For these systems, the internal energy remains constant.
In the case of a non-isolated system, the change in the internal energy is zero only if the process is cyclic. A thermodynamic process is considered cyclic if the system undergoes a series of changes and returns to its initial state.
Consider a cyclic process that returns to its initial state, undergoing a four-step process. The heat transfer along each path...
In the case of a non-isolated system, the change in the internal energy is zero only if the process is cyclic. A thermodynamic process is considered cyclic if the system undergoes a series of changes and returns to its initial state.
Consider a cyclic process that returns to its initial state, undergoing a four-step process. The heat transfer along each path...
01:24BIBO stability of continuous and discrete -time systems
System stability is a fundamental concept in signal processing, often assessed using convolution. For a system to be considered bounded-input bounded-output (BIBO) stable, any bounded input signal must produce a bounded output signal. A bounded input signal is one where the modulus does not exceed a certain constant at any point in time.
To determine the BIBO stability, the convolution integral is utilized when a bounded continuous-time input is applied to a Linear Time-Invariant (LTI) system.
To determine the BIBO stability, the convolution integral is utilized when a bounded continuous-time input is applied to a Linear Time-Invariant (LTI) system.
01:06Forced Oscillations
When an oscillator is forced with a periodic driving force, the motion may seem chaotic. The motions of such oscillators are known as transients. After the transients die out, the oscillator reaches a steady state, where the motion is periodic, and the displacement is determined.