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Published on: June 8, 2015
Local low dimensionality of atmospheric dynamics
D J Patil1, B R Hunt, E Kalnay
1Institute for Physical Science and Technology, University of Maryland, College Park, Maryland 20742, USA. dpatil@ipst.umd.edu
Physical Review Letters
|June 21, 2001
Summary
A new statistic, the bred vector (BV) dimension, measures chaos in systems. The Earth's atmosphere often shows low BV dimension, potentially improving weather forecasting accuracy.
Area of Science:
- Complex Systems Science
- Geophysics
- Atmospheric Dynamics
Background:
- Spatiotemporally chaotic systems are prevalent in nature.
- Understanding the dimensionality of these systems is crucial for prediction.
- Existing methods may not fully capture local, finite-time dynamics.
Purpose of the Study:
- Introduce a novel statistic, the bred vector (BV) dimension.
- Quantify the effective local finite-time dimensionality of chaotic systems.
- Assess the BV dimension of Earth's atmosphere and its forecasting implications.
Main Methods:
- Development of the bred vector (BV) dimension statistic.
- Application of the BV dimension to analyze spatiotemporally chaotic systems.
- Empirical analysis of atmospheric data using the BV dimension.
Main Results:
- The bred vector (BV) dimension effectively measures local finite-time dimensionality.
- Earth's atmosphere frequently exhibits a low BV dimension.
- Low BV dimension suggests potential for enhanced predictability.
Conclusions:
- The BV dimension offers a new perspective on chaotic system dynamics.
- The low dimensionality of the atmosphere presents opportunities for improved weather forecasting.
- Further research can explore leveraging BV dimension for operational forecasting models.
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