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Updated: Aug 2, 2026
13:02
Three-dimensional Particle Tracking Velocimetry for Turbulence Applications: Case of a Jet Flow
Published on: February 27, 2016
"Waves" vs. "particles" in the atmosphere's phase space: a pathway to long-range forecasting?
Michael Ghil1, Andrew W Robertson
1Department of Atmospheric Sciences and Institute of Geophysics and Planetary Physics, University of California, Los Angeles, CA 90095-1567, USA. ghil@atmos.ucla.edu
Summary
Atmospheric predictability is limited to about 10 days for detailed weather, but gross features may recur within 10–50 days. Current research explores intermittent and oscillatory approaches to predict these large-scale atmospheric patterns.
Area of Science:
- Atmospheric Science
- Meteorology
- Climate Dynamics
Background:
- Edward Lorenz established limits on atmospheric predictability ~30 years ago.
- Detailed atmospheric flow fields lose predictability after approximately 10 days.
- Gross atmospheric flow features exhibit recurrence on timescales of 10–50 days, suggesting potential for prediction.
Purpose of the Study:
- To review and discuss two distinct approaches for predicting recurrent large-scale atmospheric features.
- To explore the complementarity of "intermittency" and "periodicity" methods in atmospheric prediction.
- To outline current challenges and unsolved problems in extended-range weather forecasting.
Main Methods:
- Systematic improvements in numerical weather prediction (NWP) models, enhancing spatial resolution and physical realism.
- Theoretical studies analyzing the phase space of large-scale atmospheric motions, including observed and simulated data.
- Investigating two primary theoretical frameworks: intermittency (flow regimes, Markov chains) and periodicity (intraseasonal oscillations).
Main Results:
- Identified two main approaches: intermittency (describing weather regimes, persistence, and transitions) and periodicity (studying intraseasonal oscillations).
- These approaches, analogous to "particles" and "waves" in quantum physics, offer complementary insights into atmospheric dynamics.
- Progress has been made in both NWP and theoretical analyses, yet significant challenges remain.
Conclusions:
- Predicting recurrent atmospheric features beyond 10 days is feasible through advanced NWP and theoretical analyses.
- The intermittency and periodicity approaches provide valuable, complementary perspectives on atmospheric predictability.
- Further research is needed to address unsolved problems and improve the prediction of large-scale atmospheric phenomena.
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