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Updated: Jul 7, 2026
08:54
Measurements of Waves in a Wind-wave Tank Under Steady and Time-varying Wind Forcing
Published on: February 13, 2018
Extracting vertical winds from simulated clouds with ground-based coherent Doppler lidar.
Applied Optics
|February 28, 2008
Summary
Computer simulations assessed Doppler lidar wind field measurements at cloud interfaces. New estimators are needed for cloud conditions, as traditional methods produce biased velocity estimates.
Area of Science:
- Atmospheric science and remote sensing.
- Optical physics and instrumentation.
Background:
- Coherent Doppler lidar (CDL) is a remote sensing technology used for wind field measurements.
- Accurate wind velocity estimation is crucial for atmospheric studies, particularly at cloud interfaces.
- Existing velocity estimation techniques may exhibit biases under specific atmospheric conditions.
Purpose of the Study:
- To evaluate the performance of mean velocity estimators for solid-state coherent Doppler lidar.
- To investigate wind field measurements at cloud interfaces with deterministic velocity and aerosol backscatter profiles.
- To identify the need for new estimation techniques for challenging cloud conditions.
Main Methods:
- Computer simulations were employed to determine estimator performance.
- Performance was characterized by standard deviation and bias relative to input velocity.
- Simulations considered high signal energy data with minimal random outliers.
Main Results:
- Traditional velocity estimation techniques result in biased estimates at cloud interfaces.
- The performance of mean velocity estimators was quantitatively assessed.
- Deterministic profiles of velocity and aerosol backscatter were simulated.
Conclusions:
- A new class of estimators is required for accurate Doppler lidar measurements in cloud conditions.
- Standard estimation techniques are inadequate for reliable wind velocity profiling at cloud interfaces.
- The study highlights limitations of current methods and motivates the development of improved algorithms.
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