Doppler lidar at Observatoire de Haute Provence for wind profiling up to 75 km altitude: performance evaluation and observations

Abstract. A direct-detection Rayleigh-Mie Doppler lidar for measuring horizontal wind speed in the middle atmosphere has been deployed at Observatoire de Haute Provence (OHP) in southern France since 1993. After a recent upgrade, the instrument gained the capacity of wind profiling between 5 and 75 km altitude with high vertical and temporal resolution. The lidar comprises a monomode Nd:Yag laser emitting at 532 nm, three telescope assemblies, and a double-edge Fabry-Perot interferometer for detection of the Doppler shift in the backscattered light. In this article, we describe the instrument design, recap retrieval methodology and provide an updated error estimate for horizontal wind. The evaluation of the wind lidar performance is done using a series of twelve time-coordinated radiosoundings conducted at OHP. A point-by-point intercomparison shows a remarkably small average bias of 0.1 m/s between the lidar and the radiosonde wind profiles with a standard deviation of 2.2 m/s. We report examples of a weekly and an hourly observation series, reflecting various dynamical events in the middle atmosphere, such as a Sudden Stratospheric Warming event in January 2019 and an occurrence of a stationary gravity wave, generated by the flow over the Alps. A qualitative comparison between the wind profiles from the lidar and the ECMWF Integrated Forecast System is also discussed. Finally, we present an example of early validation of the ESA Aeolus space-borne wind lidar using its ground-based predecessor.

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Doppler lidar at Observatoire de Haute-Provence for wind profiling up to 75 km altitude: performance evaluation and observations

Atmospheric Measurement Techniques ◽

10.5194/amt-13-1501-2020 ◽

2020 ◽

Vol 13 (3) ◽

pp. 1501-1516 ◽

Cited By ~ 3

Author(s):

Sergey M. Khaykin ◽

Alain Hauchecorne ◽

Robin Wing ◽

Philippe Keckhut ◽

Sophie Godin-Beekmann ◽

...

Keyword(s):

Middle Atmosphere ◽

Direct Detection ◽

European Space Agency ◽

Horizontal Wind ◽

Doppler Lidar ◽

Qualitative Comparison ◽

Horizontal Wind Speed ◽

Wind Lidar ◽

Wind Profiles ◽

Hourly Observation

Abstract. A direct-detection Rayleigh–Mie Doppler lidar for measuring horizontal wind speed in the middle atmosphere (10 to 50 km altitude) has been deployed at Observatoire de Haute-Provence (OHP) in southern France starting from 1993. After a recent upgrade, the instrument gained the capacity of wind profiling between 5 and 75 km altitude with vertical resolution up to 115 m and temporal resolution up to 5 min. The lidar comprises a monomode Nd:Yag laser emitting at 532 nm, three telescope assemblies and a double-edge Fabry–Pérot interferometer for detection of the Doppler shift in the backscattered light. In this article, we describe the instrument design, recap retrieval methodology and provide an updated error estimate for horizontal wind. The evaluation of the wind lidar performance is done using a series of 12 time-coordinated radiosoundings conducted at OHP. A point-by-point intercomparison shows a remarkably small average bias of 0.1 m s−1 between the lidar and the radiosonde wind profiles with a standard deviation of 2.3 m s−1. We report examples of a weekly and an hourly observation series, reflecting various dynamical events in the middle atmosphere, such as a sudden stratospheric warming event in January 2019 and an occurrence of a stationary gravity wave, generated by the flow over the Alps. A qualitative comparison between the wind profiles from the lidar and the European Centre for Medium-Range Weather Forecasts (ECMWF) Integrated Forecast System is also discussed. Finally, we present an example of early validation of the European Space Agency (ESA) Aeolus space-borne wind lidar using its ground-based predecessor.

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Doppler wind lidar activities at Cabauw

10.5194/ems2021-136 ◽

2021 ◽

Author(s):

Steven Knoop ◽

Fred Bosveld ◽

Marijn de Haij ◽

Arnoud Apituley

Keyword(s):

Wind Speed ◽

Wind Profile ◽

Continuous Wave ◽

Wind Farms ◽

Data Availability ◽

Horizontal Wind ◽

Horizontal Wind Speed ◽

Low Clouds ◽

Wind Measurements ◽

Wind Lidar

Atmospheric motion and turbulence are essential parameters for weather and topics related to air quality. Therefore, wind profile measurements play an important role in atmospheric research and meteorology. One source of wind profile data are Doppler wind lidars, which are laser-based remote sensing instruments that measure wind speed and wind direction up to a few hundred meters or even a few kilometers. Commercial wind lidars use the laser wavelength of 1.5 &#181;m and therefore backscatter is mainly from aerosols while clear air backscatter is minimal, limiting the range to the boundary layer typically.We have carried out a two-year intercomparison of the ZephIR 300M (ZX Lidars) short-range wind lidar and tall mast wind measurements at Cabauw [1]. We have focused on the (height-dependent) data availability of the wind lidar under various meteorological conditions and the data quality through a comparison with in situ wind measurements at several levels in the 213m tall meteorological mast. We have found an overall availability of quality-controlled wind lidar data of 97% to 98 %, where the missing part is mainly due to precipitation events exceeding 1 mm/h or fog or low clouds below 100 m. The mean bias in the horizontal wind speed is within 0.1 m/s with a high correlation between the mast and wind lidar measurements, although under some specific conditions (very high wind speed, fog or low clouds) larger deviations are observed. This instrument is being deployed within North Sea wind farms.Recently, a scanning long-range wind lidar Windcube 200S (Leosphere/Vaisala) has been installed at Cabauw, as part of the Ruisdael Observatory program [2]. The scanning Doppler wind lidars will provide detailed measurements of the wind field, aerosols and clouds around the Cabauw site, in coordination with other instruments, such as the cloud radar.[1] Knoop, S., Bosveld, F. C., de Haij, M. J., and Apituley, A.: A 2-year intercomparison of continuous-wave focusing wind lidar and tall mast wind measurements at Cabauw, Atmos. Meas. Tech., 14, 2219&#8211;2235, 2021[2] https://ruisdael-observatory.nl/

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Comparison of Large Eddy Simulations of a convective boundary layer with wind LIDAR measurements

Advances in Science and Research ◽

10.5194/asr-8-83-2012 ◽

2012 ◽

Vol 8 (1) ◽

pp. 83-86 ◽

Cited By ~ 5

Author(s):

J. G. Pedersen ◽

M. Kelly ◽

S.-E. Gryning ◽

R. Floors ◽

E. Batchvarova ◽

...

Keyword(s):

Boundary Layer ◽

Wind Speed ◽

Geostrophic Wind ◽

Large Eddy Simulations ◽

Horizontal Wind ◽

Convective Boundary ◽

Horizontal Wind Speed ◽

Large Eddy ◽

Lidar Measurements ◽

Wind Lidar

Abstract. Vertical profiles of the horizontal wind speed and of the standard deviation of vertical wind speed from Large Eddy Simulations of a convective atmospheric boundary layer are compared to wind LIDAR measurements up to 1400 m. Fair agreement regarding both types of profiles is observed only when the simulated flow is driven by a both time- and height-dependent geostrophic wind and a time-dependent surface heat flux. This underlines the importance of mesoscale effects when the flow above the atmospheric surface layer is simulated with a computational fluid dynamics model.

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Wind profile correction algorithm based on Atmospheric Boundary Layer stability profile

10.5194/ems2021-341 ◽

2021 ◽

Author(s):

Francisco Albuquerque Neto ◽

Vinicius Almeida ◽

Julia Carelli

Keyword(s):

Boundary Layer ◽

Atmospheric Boundary Layer ◽

Wind Profile ◽

Horizontal Wind ◽

Boundary Layer Stability ◽

Correction Algorithm ◽

Horizontal Wind Speed ◽

Study Region ◽

Profile Correction ◽

Wind Profiles

In recent years, the use of radar wind profilers (RWP) at airports has grown significantly with the aim of supporting decision makers to maintain the safety of aircraft landings and takeoffs.The RWP provide vertical profiles of averaged horizontal wind speed and direction and vertical wind velocity for the entire Atmospheric Boundary Layer (ABL) and beyond. In addition, RWP with Radio-Acoustic Sounding System (RASS) are able to retrieve virtual temperature profiles in the ABL.RWP data evaluation is usually based on the so-called Doppler Beam Swinging method (DBS) which assumes homogeneity and stationarity of the wind field. Often, transient eddies violate this homogeneity and stationarity requirement. Hence, incorrect wind profiles can relate to transient eddies and present a problem for the forecast of high-impact weather phenomena in airports. This work intends to provide a method for removing outliers in such profiles based on historical data and other variables related to the Atmospheric Boundary Layer stability profile in the study region.For this study, a dataset of almost one year retrieved from a RWP LAP3000 with RASS Extension is used for a wind profile correction algorithm development.The algorithm consists of the detection of outliers in the wind profiles based on the thermodynamic structure of the ABL and the generation of the corrected profiles.Results show that the algorithm is capable of identifying and correcting unrealistic variations in speed caused by transient eddies. The method can be applied as a complement to the RWP data processing for better data reliability.&#160;Keywords: atmospheric boundary layer; stability profile; wind profile

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Shipborne Wind Measurement and Motion-induced Error Correction of a Coherent Doppler Lidar over the Yellow Sea in 2014

Atmospheric Measurement Techniques ◽

10.5194/amt-11-1313-2018 ◽

2018 ◽

Vol 11 (3) ◽

pp. 1313-1331 ◽

Cited By ~ 5

Author(s):

Xiaochun Zhai ◽

Songhua Wu ◽

Bingyi Liu ◽

Xiaoquan Song ◽

Jiaping Yin

Keyword(s):

Wind Speed ◽

Yellow Sea ◽

The Yellow Sea ◽

Horizontal Wind ◽

Measuring Error ◽

Doppler Lidar ◽

Random Errors ◽

Horizontal Wind Speed ◽

Pointing Error ◽

Coherent Doppler Lidar

Abstract. Shipborne wind observations by a coherent Doppler lidar (CDL) have been conducted to study the structure of the marine atmospheric boundary layer (MABL) during the 2014 Yellow Sea campaign. This paper evaluates uncertainties associated with the ship motion and presents the correction methodology regarding lidar velocity measurement based on modified 4-Doppler beam swing (DBS) solution. The errors of calibrated measurement, both for the anchored and the cruising shipborne observations, are comparable to those of ground-based measurements. The comparison between the lidar and radiosonde results in a bias of −0.23 ms−1 and a standard deviation of 0.87 ms−1 for the wind speed measurement, and 2.48, 8.84∘ for the wind direction. The biases of horizontal wind speed and random errors of vertical velocity are also estimated using the error propagation theory and frequency spectrum analysis, respectively. The results show that the biases are mainly related to the measuring error of the ship velocity and lidar pointing error, and the random errors are mainly determined by the signal-to-noise ratio (SNR) of the lidar backscattering spectrum signal. It allows for the retrieval of vertical wind, based on one measurement, with random error below 0.15 ms−1 for an appropriate SNR threshold and bias below 0.02 ms−1. The combination of the CDL attitude correction system and the accurate motion correction process has the potential of continuous long-term high temporal and spatial resolution measurement for the MABL thermodynamic and turbulence process.

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Snow Transport Over Mountain Crests

Journal of Glaciology ◽

10.1017/s0022143000010984 ◽

1980 ◽

Vol 26 (94) ◽

pp. 469-480 ◽

Cited By ~ 37

Author(s):

Paul M. B. Föhn

Keyword(s):

Quantitative Relationship ◽

Horizontal Wind ◽

Snow Surface ◽

Horizontal Wind Speed ◽

Ridge Crest ◽

Wind Speeds ◽

Drift Flux ◽

Strong Winds ◽

Wind Profiles ◽

Snow Transport

AbstractIn order to gain more insight into the mountain snow-transport mechanisms wind and drift flux measurements have been executed on a ridge crest (mainly during snow-storms). Horizontal wind-speed profiles, measured between 0.3 and 6 m above snow surface, show a hump-shaped course especially for strong winds. Theoretical approximations substantiate that the Bernoullian pressure decrease on the crest may be the main cause for this type of wind profile. Roughness parameters (Z0, u⋆) are determined with the aid of the wind profiles and compared with those reported in the literature. Corresponding drift density profiles coincide with steady-state drift theories as long as wind speeds are low (u1≤ 7-10 m s-1), at greater wind speeds snow plumes of 1 to 1.5 m thickness develop immediately above snow surface. Areal measurements on snow mass-balance differences between windward and lee slopes are used to approximate the total transport over the ridge crest and to derive a quantitative relationship between crest winds and drift-snow deposition on lee slopes.

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Airborne Wind Lidar Measurements of Vertical and Horizontal Winds for the Investigation of Orographically Induced Gravity Waves

Journal of Atmospheric and Oceanic Technology ◽

10.1175/jtech-d-17-0021.1 ◽

2017 ◽

Vol 34 (6) ◽

pp. 1371-1386 ◽

Cited By ~ 21

Author(s):

Benjamin Witschas ◽

Stephan Rahm ◽

Andreas Dörnbrack ◽

Johannes Wagner ◽

Markus Rapp

Keyword(s):

Wind Speed ◽

Gravity Waves ◽

Power Spectra ◽

Horizontal Resolution ◽

Vertical Wind ◽

Horizontal Wind ◽

Horizontal Wind Speed ◽

Lidar Measurements ◽

Vertical Wind Speed ◽

Wind Lidar

AbstractAirborne coherent Doppler wind lidar measurements, acquired during the Gravity Wave Life-Cycle (GW-LCYCLE) I field campaign performed from 2 to 14 December 2013 in Kiruna, Sweden, are used to investigate internal gravity waves (GWs) induced by flow across the Scandinavian Mountains. Vertical wind speed is derived from lidar measurements with a mean bias of less than 0.05 m s−1 and a standard deviation of 0.2 m s−1 by correcting horizontal wind projections onto the line-of-sight direction by means of ECMWF wind data. The horizontal wind speed and direction are retrieved from lidar measurements by applying a velocity–azimuth display scan and a spectral accumulation technique, leading to a horizontal resolution of about 9 km along the flight track and a vertical resolution of 100 m, respectively. Both vertical and horizontal wind measurements are valuable for characterizing GW properties as demonstrated by means of a flight performed on 13 December 2013 acquired during weather conditions favorable for orographic GW excitation. Wavelet power spectra of the vertical wind speed indicate that the horizontal GW wavelengths lay mainly between 10 and 30 km and that the GW amplitude above the mountain ridge decreases with increasing altitude. Additionally, the perturbations of the horizontal wind speed are analyzed, showing horizontal wavelengths in the excitation region of 100–125 km with upwind-tilted wave fronts. By means of elevation power spectra, it is revealed that vertical wind power spectra are dominated by the short-wave elevation part, whereas horizontal wind perturbations are dominated by the long-wave part.

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Development of Synergetic-Active Sensor-System for Evaluation of Observations by Earthcare

EPJ Web of Conferences ◽

10.1051/epjconf/202023707011 ◽

2020 ◽

Vol 237 ◽

pp. 07011

Author(s):

Hajime Okamoto ◽

Kaori Sato ◽

Masahiro Fujikawa ◽

Eiji Oikawa ◽

Tomoaki Nishizawa ◽

...

Keyword(s):

Direct Detection ◽

Cloud Microphysics ◽

Sensor System ◽

High Spectral Resolution ◽

Horizontal Wind ◽

Observation System ◽

Active Sensor ◽

Wind Lidar ◽

Multiple Field ◽

Doppler Wind Lidar

We develop the synergetic ground-based active-sensor-system for the evaluation of observations by space-borne lidars. The system consists of second version of multi-field-view multiple-scattering polarization lidar (MFMSPL-2), multiple-field-of-view high spectral resolution polarization lidar, direct-detection Doppler wind lidar, coherent Doppler wind lidar and 94GHz cloud profiling radar. The system can simulate observed signals from sensors onboard the joint Japanese/European mission Earth Clouds, Aerosols and Radiation Explorer (EarthCARE). The observation system can provide unique opportunity to study interaction of cloud microphysics, aerosol microphysics, vertical air motion and vertical distribution of horizontal wind and it will lead to evaluate cloud-convective parameterization and to reduce uncertainties in climate change predictions.

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Uncertainty model for dual-Doppler retrievals of wind speed and wind direction

10.5194/amt-2020-321 ◽

2020 ◽

Author(s):

Nikola Vasiljević ◽

Michael Courtney ◽

Anders Tegtmeier Pedersen

Keyword(s):

Wind Speed ◽

Elevation Angle ◽

Velocity Estimation ◽

Horizontal Wind ◽

Doppler Lidar ◽

Horizontal Wind Speed ◽

Uncertainty Model ◽

Lidar Measurements ◽

Python Package ◽

Propagation Of Uncertainties

Abstract. In this paper we present an analytical model for estimating the uncertainty of the horizontal wind speed based on dual-Doppler lidar measurements. The model follows the propagation of uncertainties method and takes into account the uncertainty of radial velocity estimation, azimuth and elevation pointing angles, and ranging. The model is achieved by coupling ranging and elevation angle to uncertainty of the probed wind speed through a simple power-law shear model. The model has been implemented in Python and made freely available through as the Python package YADDUM.

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Horizontal Wind Speed motion-induced error assessment on a floating Doppler Wind lidar

10.5194/egusphere-egu21-7656 ◽

2021 ◽

Author(s):

Andreu Salcedo-Bosch ◽

Joan Farré-Guarné ◽

Josep Sala-Álvarez ◽

Javier Villares-Piera ◽

Robin Tanamachi ◽

...

Keyword(s):

Wind Speed ◽

Wind Profile ◽

Continuous Wave ◽

Superposition Principle ◽

Translational Motion ◽

Horizontal Wind ◽

Error Assessment ◽

Horizontal Wind Speed ◽

Wind Lidar ◽

Doppler Wind Lidar

A wind retrieval simulator of a floating Doppler Wind Lidar (DWL) with six Degrees of Freedom (DoF) in its motion is presented. The simulator considers a continuous-wave, conically scanning, floating DWL which retrieves the local wind profile from 50 line of sight (LoS) radial velocity measurements per scan. Rotational and translational motion effects over horizontal wind speed (HWS) measurements are studied parametrically. The 6 DoF motion framework as well as the most important buoy motion equations are based on the model presented in [1].Each rotational and translational motion is simulated as 1 second sinusoidal signal defined by an amplitude, frequency and motion phase. In order to study the problem of motion-induced error on the retrieved HWS, a dimension reduction is needed (22 variables). A consideration followed in the literature [2] to alleviate the problem is to set the same motional frequency (f=0.3 Hz) for all DoF, a wind vector with constant HWS and null vertical wind speed (VWS). Moreover, the parametric study is carried out under certain constraints in order to finally reduce the problem dimensionality to three, which enables the generation of tri-dimensional colorplots of the error on the retrieved HWS.Simulation results show that in the presence of motion, HWS error has a strong dependency on FDWL initial scan phase. Moreover, the directions of the rotation axis and translational velocity vector (with respect to wind direction, WD) show great impact on HWS error. For translational motion, a 3 DoF superposition principle is corroborated.The simulator is as a useful tool for understanding particular lidar motion scenarios and their contributions to HWS measurements error. However, further analysis of the effect of lidar initial scan phase is needed. Additionally, these simulations are conducted under idealized assumptions of horizontally homogeneous wind profiles in the vicinity of the FDWL. Simulations using non-homogeneous wind fields (e.g., turbulence, air mass boundaries) would give insights on how well floating lidars can be expected to retrieve the wind profile in these common scenarios.AcknowledgementsThis work was supported via Spanish Government&#8211;European Regional Development Funds project PGC2018-094132-B-I00 and H2020 ACTRIS-IMP (GA-871115). The European Institute of Innovation and Technology (EIT), KIC InnoEnergy project NEPTUNE (Offshore Metocean Data Mea-suring Equipment and Wind, Wave and Current Analysis and ForecastingSoftware, call FP7) supported measurements campaigns. CommSensLab isa Mar&#237;a-de-Maeztu Unit of Excellence funded by the Agencia Estatal de Investigaci&#243;n (Spanish National Science Foundation). The work of Andreu Salcedo-Bosch was supported by the &#8220;Ag&#232;ncia de Gesti&#243; d&#8217;Ajuts Universitaris i de la Recerca (AGAUR)&#8221;, Generalitat de Catalunya, under Grant no. 2020 FISDU 00455.References[1] F. Kelberlau, V. Neshaug, L. L&#248;nseth, T. Bracchi, and J. Mann, &#8220;Taking the Motion out of Floating Lidar: Turbulence Intensity Estimates with a Continuous-Wave Wind Lidar,&#8221; Remote Sens., vol. 12, no. 898, 2020.[2] J. Tiana-Alsina, F. Rocadenbosch, and M. A. Gutierrez-Antunano, &#8220;Vertical Azimuth Display simulator for wind-Doppler lidar error assessment,&#8221; in 2017 IEEE Int. Geosci. Remote. Se. (IGARSS). IEEE, Jul. 2017.

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