Initial Assessment of the Performance of the First Wind Lidar in Space on Aeolus

Soon after its successful launch in August 2018, the spaceborne wind lidar ALADIN (Atmospheric LAser Doppler INstrument) on-board ESA’s Earth Explorer satellite Aeolus has demonstrated to provide atmospheric wind profiles on a global scale. Being the first ever Doppler Wind Lidar (DWL) instrument in space, ALADIN contributes to the improvement in numerical weather prediction (NWP) by measuring one component of the horizontal wind vector. The performance of the ALADIN instrument was assessed by a team from ESA, DLR, industry, and NWP centers during the first months of operation. The current knowledge about the main contributors to the random and systematic errors from the instrument will be discussed. First validation results from an airborne campaign with two wind lidars on-board the DLR Falcon aircraft will be shown.

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ESA’s spaceborne lidar mission ADM-Aeolus; project status and preparations for launch

EPJ Web of Conferences ◽

10.1051/epjconf/201817604007 ◽

2018 ◽

Vol 176 ◽

pp. 04007 ◽

Cited By ~ 1

Author(s):

Anne Grete Straume ◽

Anders Elfving ◽

Denny Wernham ◽

Frank de Bruin ◽

Thomas Kanitz ◽

...

Keyword(s):

Optical Properties ◽

Weather Prediction ◽

Atmospheric Dynamics ◽

The Novel ◽

Aerosol Optical Properties ◽

Climate Research ◽

Wind Lidar ◽

Core Mission ◽

Wind Profiles ◽

Doppler Wind Lidar

ESA’s Doppler Wind lidar mission, the Atmospheric Dynamics Mission (ADM-Aeolus, hereafter abbreviated to Aeolus), was chosen as an Earth Explorer Core mission within the Living Planet Programme in 1999. It shall demonstrate the potential of space-based Doppler Wind lidars for operational measurements of wind profiles and their use in Numerical Weather Prediction (NWP) and climate research. Spin-off products are profiles of cloud and aerosol optical properties. Aeolus carries the novel Doppler Wind lidar instrument ALADIN. The mission prime is Airbus Defence & Space UK (ADS-UK), and the instrument prime is Airbus Defence & Space France (ADS-F).

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An Observing System Simulation Experiment (OSSE) to Assess the Impact of Doppler Wind Lidar (DWL) Measurements on the Numerical Simulation of a Tropical Cyclone

Advances in Meteorology ◽

10.1155/2010/743863 ◽

2010 ◽

Vol 2010 ◽

pp. 1-14 ◽

Cited By ~ 9

Author(s):

Lei Zhang ◽

Zhaoxia Pu

Keyword(s):

Numerical Simulation ◽

Tropical Cyclone ◽

Mesoscale Model ◽

Weather Prediction ◽

Three Dimensional ◽

Wrf Model ◽

Wind Lidar ◽

Wind Profiles ◽

The Impact ◽

Doppler Wind Lidar

The importance of wind observations has been recognized for many years. However, wind observations—especially three-dimensional global wind measurements—are very limited. A satellite-based Doppler Wind Lidar (DWL) is proposed to measure three-dimensional wind profiles using remote sensing techniques. Assimilating these observations into a mesoscale model is expected to improve the performance of the numerical weather prediction (NWP) models. In order to examine the potential impact of the DWL three-dimensional wind profile observations on the numerical simulation and prediction of tropical cyclones, a set of observing simulation system experiments (OSSEs) is performed using the advanced research version of the Weather Research and Forecasting (WRF) model and its three-dimensional variational (3DVAR) data assimilation system. Results indicate that assimilating the DWL wind observations into the mesoscale numerical model has significant potential for improving tropical cyclone track and intensity forecasts.

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First Results from the German Cal/Val Activities for Aeolus

EPJ Web of Conferences ◽

10.1051/epjconf/202023701008 ◽

2020 ◽

Vol 237 ◽

pp. 01008 ◽

Cited By ~ 1

Author(s):

Holger Baars ◽

Alexander Geiß ◽

Ulla Wandinger ◽

Alina Herzog ◽

Ronny Engelmann ◽

...

Keyword(s):

Direct Detection ◽

Weather Prediction ◽

European Space Agency ◽

High Spectral Resolution ◽

Dual Channel ◽

Space Agency ◽

First Results ◽

Global Coverage ◽

Wind Lidar ◽

Doppler Wind Lidar

On 22nd August 2018, the European Space Agency (ESA) launched the first direct detection Doppler wind lidar into space. Operating at 355 nm and acquiring signals with a dual channel receiver, it allows wind observations in clear air and particle-laden regions of the atmosphere. Furthermore, particle optical properties can be obtained using the High Spectral Resolution Technique Lidar (HSRL) technique. Measuring with 87 km horizontal and 0.25-2 km vertical resolution between ground and up to 30 km in the stratosphere, the global coverage of Aeolus observations shall fill gaps in the global observing system and thus help improving numerical weather prediction. Within this contribution, first results from the German initiative for experimental Aeolus validation are presented and discussed. Ground-based wind and aerosol measurements from tropospheric radar wind profilers, Doppler wind lidars, radiosondes, aerosol lidars and cloud radars are utilized for that purpose.

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Evaluation of wind profiles from the NERC MST Radar, Aberystwyth, UK

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-7-4589-2014 ◽

2014 ◽

Vol 7 (5) ◽

pp. 4589-4621

Author(s):

C. F. Lee ◽

G. Vaughan ◽

D. A. Hooper

Keyword(s):

Wind Speed ◽

Standard Error ◽

Random Error ◽

Sampling Error ◽

Weather Prediction ◽

Horizontal Wind ◽

Wind Speeds ◽

Mst Radar ◽

Wind Profiles ◽

Aspect Sensitivity

Abstract. This study quantifies the uncertainties in winds measured by the Aberystwyth Mesosphere-Stratosphere-Troposphere (MST) radar (52.4° N, 4.0° W), before and after its renovation in March 2011. 127 radiosondes provide an independent measure of winds. Differences between radiosonde and radar-measured horizontal winds are correlated with long-term averages of vertical velocities, suggesting an influence from local mountain waves. These local influences are an important consideration when using radar winds as a measure of regional conditions, particularly for numerical weather prediction. In those applications, local effects represent a source of sampling error additional to the inherent uncertainties in the measurements themselves. The radar renovation improved the SNR of measurements, with correspondingly improved altitude coverage. It also corrected an under-estimate of horizontal wind speeds attributed to beam formation problems, due to component failure pre-renovation. The standard error in radar-measured winds averaged over half-an-hour increases with wind speed and altitude, and is 0.6–2.5 m s−1 (5–20% of wind speed) for post-renovation horizontal winds. Pre-renovation values are typically 0.4 m s−1 (0.03 m s−1) larger. The standard error in radial velocities is < 0.04 m s−1. Eight weeks of special radar operation are used to investigate the effects of echo power aspect sensitivity. Corrections for echo power aspect sensitivity remove an underestimate of horizontal wind speeds, however aspect sensitivity is azimuthally anisotropic at the scale of routine observations (≈ 1 h). This anisotropy introduces additional random error into wind profiles. For winds averaged over half-an-hour, the random error is around 3.5% above 8 km, but as large as 4.5% in the mid-troposphere.

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Development of Direct-Detection Doppler Wind Lidar for Vertical Atmospheric Motion

EPJ Web of Conferences ◽

10.1051/epjconf/202023706006 ◽

2020 ◽

Vol 237 ◽

pp. 06006

Author(s):

Shoken Ishii ◽

Makoto Aoki ◽

Kanna Tominaga ◽

Tomoaki Nishizawa ◽

Yoshitaka Jin ◽

...

Keyword(s):

Wind Profile ◽

Direct Detection ◽

Weather Prediction ◽

Information And Communications Technology ◽

Good Precision ◽

Remote Sensing Technique ◽

High Vertical Resolution ◽

Wind Lidar ◽

Atmospheric Phenomena ◽

Doppler Wind Lidar

Wind is fundamental in many atmospheric phenomena. Global wind profile observation is important to improve numerical weather prediction (NWP) and various meteorological studies. Wind profile observations are measured mainly by radiosonde networks. A Doppler Wind Lidar (DWL) is a useful remote sensing technique for wind measurement. DWL would provide us with a wind profile having high vertical resolution, low bias, and good precision. The National Institute of Information and Communications Technology (NICT) studies DWL has been developing various DWL. In the paper, we report development of a 355-nm direct-detection DWL and describe recent results of a 2-µm coherent DWL at NICT.

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

10.5194/amt-2019-385 ◽

2019 ◽

Author(s):

Sergey M. Khaykin ◽

Alain Hauchecorne ◽

Robin Wing ◽

Philippe Keckhut ◽

Sophie Godin-Beekmann ◽

...

Keyword(s):

Middle Atmosphere ◽

Direct Detection ◽

Horizontal Wind ◽

Doppler Lidar ◽

Qualitative Comparison ◽

Horizontal Wind Speed ◽

Early Validation ◽

Wind Lidar ◽

Wind Profiles ◽

Hourly Observation

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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Aeolus Calibration, Validation and Science Campaigns

10.5194/egusphere-egu2020-19778 ◽

2020 ◽

Author(s):

Thorsten Fehr ◽

Vassilis Amiridis ◽

Sebastian Bley ◽

Philippe Cocquerez ◽

Christian Lemmerz ◽

...

Keyword(s):

Current Knowledge ◽

Interesting Case ◽

Saharan Dust ◽

Aerosol Layer ◽

Satellite Mission ◽

Core Element ◽

Wind Lidar ◽

The Tropics ◽

Doppler Wind Lidar

Since 2007, a series of ESA supported airborne campaigns have been essential to the development of the Aeolus Doppler Wind Lidar satellite mission, which was successfully launched on 22 September 2018 and is providing a novel wind and aerosol profile data.A core element of the Aeolus Cal/Val activities is DLR&#8217;s A2D wind lidar on-board the DLR Falcon aircraft, an airborne demonstrator for the Aeolus ALADIN satellite instrument flown in combination with the 2-&#181;m Doppler Wind Lidar reference system. Following the pre-launch WindVal-I and &#8211;II campaigns in 2015 and 2016, a number of calibration and validation campaigns have been successfully implemented: WindVal-III providing early Cal/Val results in November 2018 only three months after the Aeolus launch, AVATAR-E in May 2019 focussing on the Cal/Val over Central Europe, and AVATAR-I in September 2019 providing Cal/Val information in the North Atlantic and Arctic flying from Iceland.The airborne validation is also being supported through balloon flights in the tropical UTLS and lower stratosphere in the frame of the CNES Strat&#233;ole-2 stratospheric balloon activities. In the frame of the ESA supported pre-Strat&#233;ole-2 campaign, eight stratospheric balloons have been launched from the Seychelles in November/December 2019 providing unique upper level wind data for the Aeolus validation.The largest impact of the Aeolus observations is expected in the Tropics, and in particular over the Tropical oceans, where only a limited number of wind profile information is provided by ground based observations. Aeolus provides key direct measurements which are of importance to correctly constrain the wind fields in models. In addition, Aeolus observations have the potential to further enhance our current knowledge on aerosols and clouds by globally providing optical properties products that include atmospheric backscatter and extinction coefficient profiles, lidar ratio profiles and scene classification. In the tropics, a particularly interesting case is the outflow of Saharan dust and its impact on micro-physics in tropical cloud systems. The region off the coast of West Africa allows the study of the Saharan Aerosol layer, African Easterly Waves and Jets, Tropical Easterly Jet, as well as the deep convection in ITCZ.&#160;Together with international partners, ESA is currently implementing a Tropical campaign in July 2020 with its base in Cape Verde that comprises both airborne and ground-based activities addressing the tropical winds and aerosol validation, as well as science objectives. The airborne component includes the DLR Falcon-20 carrying the A2D and 2-&#181;m Doppler Wind lidars, the NASA P-3 Orion with the DAWN and HALO lidar systems, the APR Ku-, Ka- and W-band Doppler radar and drop sondes, and a Slovenian small aircraft providing in-situ information from aethalometers, nephelometers and optical particle counters. The ground-based component led by the National Observatory of Athens is a collaboration of European teams providing aerosol and cloud measurements with a range of lidar, radar and radiometer systems, as well as a drone providing in-situ aerosol observations. In addition, the participation airborne capabilities by NOAA and LATMOS/Meteo France are currently being investigated.This paper will provide a summary of the Aeolus campaign focussing on the planned tropical

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ESA’s Lidar Missions Aeolus and EarthCARE

EPJ Web of Conferences ◽

10.1051/epjconf/202023701006 ◽

2020 ◽

Vol 237 ◽

pp. 01006

Author(s):

Thomas Kanitz ◽

Alessandra Ciapponi ◽

Alessia Mondello ◽

Alessandro D’Ottavi ◽

Ana Baselga Mateo ◽

...

Keyword(s):

Weather Prediction ◽

Global Dynamics ◽

Major Step ◽

Space Applications ◽

Fully Integrated ◽

Ground Testing ◽

The Earth ◽

Wind Lidar ◽

Wind Profiles ◽

Uv Lasers

ESAs Earth Explorer Aeolus was launched in August 2018. Aboard the first spaceborne wind lidar ALADIN (Atmospheric LAser Doppler INstrument) was switched on in early September 2018 and demonstrated the capability to provide atmospheric wind profiles globally from particle and molecular backscatter. In doing so, it will contribute to the improvement in numerical weather prediction (NWP) and the understanding of global dynamics. At the same, it is a major step for powerful and frequency stabilized ultraviolet (UV) lasers for space applications. In parallel, ESA and its partners continue the development of this technology by setting up further ground tests based on Aeolus, and preparing the next milestone with ATLID (ATmospheric LIDar) for the Earth Cloud, Aerosol and Radiation Explorer (EarthCARE) mission. ATLID is currently fully integrated and getting prepared for its on-ground testing.

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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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