Calculation of area-averaged vertical profiles of the horizontal wind velocity from volume-imaging lidar data

1992 ◽  
Vol 97 (D17) ◽  
pp. 18395 ◽  
Author(s):  
J. L. Schols ◽  
E. W. Eloranta
Keyword(s):  
Wind Velocity ◽  
Horizontal Wind ◽  
Lidar Data ◽  
Vertical Profiles ◽  
Volume Imaging

scholarly journals Vertical profiles of the 3-D wind velocity retrieved from multiple wind lidars performing triple range-height-indicator scans

2017 ◽  
Vol 10 (2) ◽  
pp. 431-444 ◽  
Author(s):  
Mithu Debnath ◽  
G. Valerio Iungo ◽  
Ryan Ashton ◽  
W. Alan Brewer ◽  
Aditya Choukulkar ◽  
...  
Keyword(s):  
Wind Velocity ◽  
High Frequency ◽  
Error Propagation ◽  
Good Accuracy ◽  
Data Retrieval ◽  
Horizontal Wind ◽  
Experimental Setup ◽  
Vertical Profiles ◽  
Meteorological Tower ◽  
Sonic Anemometers

Abstract. Vertical profiles of 3-D wind velocity are retrieved from triple range-height-indicator (RHI) scans performed with multiple simultaneous scanning Doppler wind lidars. This test is part of the eXperimental Planetary boundary layer Instrumentation Assessment (XPIA) campaign carried out at the Boulder Atmospheric Observatory. The three wind velocity components are retrieved and then compared with the data acquired through various profiling wind lidars and high-frequency wind data obtained from sonic anemometers installed on a 300 m meteorological tower. The results show that the magnitude of the horizontal wind velocity and the wind direction obtained from the triple RHI scans are generally retrieved with good accuracy. However, poor accuracy is obtained for the evaluation of the vertical velocity, which is mainly due to its typically smaller magnitude and to the error propagation connected with the data retrieval procedure and accuracy in the experimental setup.

scholarly journals Vertical profiles of the 3D wind velocity retrieved from multiple wind LiDARs performing triple range-height-indicator scans

2016 ◽  
Author(s):  
M. Debnath ◽  
G. V. Iungo ◽  
R. Ashton ◽  
W. A. Brewer ◽  
A. Choukulkar ◽  
...  
Keyword(s):  
Wind Velocity ◽  
High Frequency ◽  
Error Propagation ◽  
Good Accuracy ◽  
Data Retrieval ◽  
Horizontal Wind ◽  
Experimental Setup ◽  
Vertical Profiles ◽  
Meteorological Tower ◽  
Sonic Anemometers

Abstract. Vertical profiles of the 3D wind velocity are retrieved from triple range-height-indicator (RHI) scans performed with multiple simultaneous scanning Doppler wind lidars. This test is part of the eXperimental Planetary boundary layer Instrumentation Assessment (XPIA) campaign carried out at the Boulder Atmospheric Observatory. The three wind velocity components are retrieved, then compared with the data acquired through various profiling wind lidars, and high-frequency wind data obtained from sonic anemometers installed on a 300-m meteorological tower. The results show that the magnitude of the horizontal wind velocity and the wind direction obtained from the triple RHI scans are generally retrieved with good accuracy. However, poor accuracy is obtained for the evaluation of the vertical velocity, which is mainly due to its typically smaller magnitude, and the error propagation connected with the data retrieval procedure and accuracy in the experimental setup.

Observations of Small-Scale Turbulence and Energy Dissipation Rates in the Cloudy Boundary Layer

2006 ◽  
Vol 63 (5) ◽  
pp. 1451-1466 ◽  
Author(s):  
Holger Siebert ◽  
Katrin Lehmann ◽  
Manfred Wendisch
Keyword(s):  
Boundary Layer ◽  
Energy Dissipation ◽  
Wind Velocity ◽  
Turbulence Theory ◽  
Horizontal Wind ◽  
Inertial Subrange ◽  
Intermittent Flow ◽  
Small Scale ◽  
Dissipation Rates ◽  
Wide Range

Abstract Tethered balloon–borne measurements with a resolution in the order of 10 cm in a cloudy boundary layer are presented. Two examples sampled under different conditions concerning the clouds' stage of life are discussed. The hypothesis tested here is that basic ideas of classical turbulence theory in boundary layer clouds are valid even to the decimeter scale. Power spectral densities S( f ) of air temperature, liquid water content, and wind velocity components show an inertial subrange behavior down to ≈20 cm. The mean energy dissipation rates are ∼10−3 m2 s−3 for both datasets. Estimated Taylor Reynolds numbers (Reλ) are ∼104, which indicates the turbulence is fully developed. The ratios between longitudinal and transversal S( f ) converge to a value close to 4/3, which is predicted by classical turbulence theory for local isotropic conditions. Probability density functions (PDFs) of wind velocity increments Δu are derived. The PDFs show significant deviations from a Gaussian distribution with longer tails typical for an intermittent flow. Local energy dissipation rates ɛτ are derived from subsequences with a duration of τ = 1 s. With a mean horizontal wind velocity of 8 m s−1, τ corresponds to a spatial scale of 8 m. The PDFs of ɛτ can be well approximated with a lognormal distribution that agrees with classical theory. Maximum values of ɛτ ≈ 10−1 m2 s−3 are found in the analyzed clouds. The consequences of this wide range of ɛτ values for particle–turbulence interaction are discussed.

scholarly journals Robust Nonparametric Methods of Statistical Analysis of Wind Velocity Components in Acoustic Sounding of the Lower Layer of the Atmosphere

Symmetry ◽  
2019 ◽  
Vol 11 (8) ◽  
pp. 961 ◽  
Author(s):  
Krasnenko ◽  
Simakhin ◽  
Shamanaeva ◽  
Cherepanov
Keyword(s):  
Statistical Analysis ◽  
Wind Velocity ◽  
Numerical Experiments ◽  
Lower Layer ◽  
Statistical Characteristics ◽  
Nonparametric Method ◽  
Vertical Profiles ◽  
Acoustic Sounding ◽  
Sodar Data ◽  
First Four Moments

Statistical analysis of the results of minisodar measurements of vertical profiles of wind velocity components in a 5–200 m layer of the atmosphere shows that this problem belongs to the class of robust nonparametric problems of mathematical statistics. In this work, a new consecutive nonparametric method of adaptive pendular truncation is suggested for outlier detection and selection in sodar data. The method is implemented in a censoring algorithm. The efficiency of the suggested algorithm is tested in numerical experiments. The algorithm has been used to calculate statistical characteristics of wind velocity components, including vertical profiles of the first four moments, the correlation coefficient, and the autocorrelation and structure functions of wind velocity components. The results obtained are compared with classical sample estimates.

scholarly journals VHF volume-imaging radar observation of aspect-sensitive scatterers tilted in mountain waves above a convective boundary layer

2005 ◽  
Vol 23 (4) ◽  
pp. 1139-1145 ◽  
Author(s):  
R. M. Worthington
Keyword(s):  
Gravity Waves ◽  
Air Flow ◽  
Horizontal Wind ◽  
Convective Boundary ◽  
Mountain Waves ◽  
Imaging Radar ◽  
Mu Radar ◽  
Volume Imaging ◽  
Wind Measurements ◽  
To Receive

Abstract. Thin stable atmospheric layers cause VHF radars to receive increased echo power from near zenith. Layers can be tilted from horizontal, for instance by gravity waves, and the direction of VHF "glinting" is measurable by spatial domain interferometry or many-beam Doppler beam swinging (DBS). This paper uses the Middle and Upper atmosphere (MU) radar, Shigaraki, Japan as a volume-imaging radar with 64-beam DBS, to show tilting of layers and air flow in mountain waves. Tilt of aspect-sensitive echo power from horizontal is nearly parallel to air flow, as assumed in earlier measurements of mountain-wave alignment. Vertical-wind measurements are self-consistent from different beam zenith angles, despite the combined effects of aspect sensitivity and horizontal-wind gradients.

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