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Visually Based Characterization of the Incipient Particle Motion in Regular Substrates: From Laminar to Turbulent Conditions
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Extending a surface-layer Cn2 model for strongly stratified conditions utilizing a numerically generated turbulence
Optics Express
|May 4, 2016
Summary
A new model estimates atmospheric refractive index structure parameter (Cn2) across all stability conditions, improving upon older models limited to unstable environments. This enhanced model shows good agreement with observational data.
Area of Science:
- Atmospheric science
- Optical turbulence
- Meteorology
Background:
- The Wyngaard et al. (1971) model estimates Cn2 using meteorological data but is limited to unstable atmospheric conditions.
- Existing models struggle with stable atmospheric conditions, particularly at night, limiting their practical application.
Purpose of the Study:
- To develop an improved Cn2 model applicable across a wide range of atmospheric stabilities, including strongly stratified conditions.
- To overcome the limitations of previous models in stable atmospheric regimes.
Main Methods:
- Utilized an extensive turbulence dataset generated via direct numerical simulation (DNS).
- Constructed a novel Cn2 model incorporating insights from high-fidelity turbulence data.
- Validated the new model using four weeks of Cn2 data from Mauna Loa Observatory, Hawaii.
Main Results:
- The new Cn2 model demonstrates applicability across diverse atmospheric stabilities, including very stable conditions.
- Validation against observational data from Mauna Loa showed reasonably good agreement between estimated and observed Cn2 values.
Conclusions:
- The developed Cn2 model offers improved performance, especially in stable atmospheric conditions, expanding its utility.
- This research provides a more robust tool for estimating optical turbulence parameters in various atmospheric environments.
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