Articles | Volume 14, issue 2
https://doi.org/10.5194/amt-14-1715-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-14-1715-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
02 Mar 2021
Research article |
| 02 Mar 2021
| 02 Mar 2021
A Compact Rayleigh Autonomous Lidar (CORAL) for the middle atmosphere
Deutsches Zentrum für Luft- und Raumfahrt, Institut für Physik der Atmosphäre, Oberpfaffenhofen, Germany
Natalie Kaifler
Deutsches Zentrum für Luft- und Raumfahrt, Institut für Physik der Atmosphäre, Oberpfaffenhofen, Germany
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Jens Fiedler, Gerd Baumgarten, Michael Gerding, Torsten Köpnick, Reik Ostermann, and Bernd Kaifler
EGUsphere, https://doi.org/10.5194/egusphere-2025-1995, https://doi.org/10.5194/egusphere-2025-1995, 2025
This preprint is open for discussion and under review for Geoscientific Instrumentation, Methods and Data Systems (GI).
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We developed a system for frequency control and monitoring of pulsed high-power lasers. It works in real-time, controls the laser cavity length, and performs a spectral analyzes of each individual laser pulse. The motivation for this work was to improve the retrieval of Doppler winds measured by lidar in the middle atmosphere by taking the frequency stability of the lidar transmitter into account.
Natalie Kaifler, Bernd Kaifler, Markus Rapp, Guiping Liu, Diego Janches, Gerd Baumgarten, and Jose-Luis Hormaechea
Atmos. Chem. Phys., 24, 14029–14044, https://doi.org/10.5194/acp-24-14029-2024, https://doi.org/10.5194/acp-24-14029-2024, 2024
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Noctilucent clouds (NLCs) are silvery clouds that can be viewed during twilight and indicate atmospheric conditions like temperature and water vapor in the upper mesosphere. High-resolution measurements from a remote sensing laser instrument provide NLC height, brightness, and occurrence rate since 2017. Most observations occur in the morning hours, likely caused by strong tidal winds, and NLC ice particles are thus transported from elsewhere to the observing location in the Southern Hemisphere.
Robert Reichert, Natalie Kaifler, and Bernd Kaifler
Atmos. Meas. Tech., 17, 4659–4673, https://doi.org/10.5194/amt-17-4659-2024, https://doi.org/10.5194/amt-17-4659-2024, 2024
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Imagine you want to determine how quickly the pitch of a passing ambulance’s siren changes. If the vehicle is traveling slowly, the pitch changes only slightly, but if it is traveling fast, the pitch also changes rapidly. In a similar way, the wind in the middle atmosphere modulates the wavelength of atmospheric gravity waves. We have investigated the question of how strong the maximum wind may be so that the change in wavelength can still be determined with the help of wavelet transformation.
Natalie Kaifler, Bernd Kaifler, Markus Rapp, and David C. Fritts
Atmos. Chem. Phys., 23, 949–961, https://doi.org/10.5194/acp-23-949-2023, https://doi.org/10.5194/acp-23-949-2023, 2023
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We used a lidar to measure polar mesospheric clouds from a balloon floating in the upper stratosphere. The thin-layered ice clouds at 83 km altitude are perturbed by waves. The high-resolution lidar soundings reveal small-scale structures induced by the breaking of those waves. We study these patterns and find that they occur very often. We show their morphology and discuss associated dynamical physical processes, which help to interpret case studies and to guide modelling.
Natalie Kaifler, Bernd Kaifler, Markus Rapp, and David C. Fritts
Earth Syst. Sci. Data, 14, 4923–4934, https://doi.org/10.5194/essd-14-4923-2022, https://doi.org/10.5194/essd-14-4923-2022, 2022
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We measured polar mesospheric clouds (PMCs), our Earth’s highest clouds at the edge of space, with a Rayleigh lidar from a stratospheric balloon. We describe how we derive the cloud’s brightness and discuss the stability of the gondola pointing and the sensitivity of our measurements. We present our high-resolution PMC dataset that is used to study dynamical processes in the upper mesosphere, e.g. regarding gravity waves, mesospheric bores, vortex rings, and Kelvin–Helmholtz instabilities.
Kevin Ohneiser, Albert Ansmann, Bernd Kaifler, Alexandra Chudnovsky, Boris Barja, Daniel A. Knopf, Natalie Kaifler, Holger Baars, Patric Seifert, Diego Villanueva, Cristofer Jimenez, Martin Radenz, Ronny Engelmann, Igor Veselovskii, and Félix Zamorano
Atmos. Chem. Phys., 22, 7417–7442, https://doi.org/10.5194/acp-22-7417-2022, https://doi.org/10.5194/acp-22-7417-2022, 2022
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We present and discuss 2 years of long-term lidar observations of the largest stratospheric perturbation by wildfire smoke ever observed. The smoke originated from the record-breaking Australian fires in 2019–2020 and affects climate conditions and even the ozone layer in the Southern Hemisphere. The obvious link between dense smoke occurrence in the stratosphere and strong ozone depletion found in the Arctic and in the Antarctic in 2020 can be regarded as a new aspect of climate change.
Stefanie Knobloch, Bernd Kaifler, and Markus Rapp
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2021-310, https://doi.org/10.5194/amt-2021-310, 2022
Preprint withdrawn
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The study tests the quality of temperature measurements from the airborne Rayleigh lidar ALIMA. The ALIMA system was first used during the SouthTRAC campaign in September 2019 in the vicinity of the Southern Andes, Drake Passage and Antarctic Peninsula. The raw lidar measurements are additionally simulated based on reanalysis data for one research flight. Different types of uncertainty influencing the accuracy of the temperature measurements are studied, e.g. atmospheric and technical sources.
Emranul Sarkar, Alexander Kozlovsky, Thomas Ulich, Ilkka Virtanen, Mark Lester, and Bernd Kaifler
Atmos. Meas. Tech., 14, 4157–4169, https://doi.org/10.5194/amt-14-4157-2021, https://doi.org/10.5194/amt-14-4157-2021, 2021
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The biasing effect in meteor radar temperature has been a pressing issue for the last 2 decades. This paper has addressed the underlying reasons for such a biasing effect on both theoretical and experimental grounds. An improved statistical method has been developed which allows atmospheric temperatures at around 90 km to be measured with meteor radar in an independent way such that any subsequent bias correction or calibration is no longer required.
Bernd Kaifler, Dimitry Rempel, Philipp Roßi, Christian Büdenbender, Natalie Kaifler, and Volodymyr Baturkin
Atmos. Meas. Tech., 13, 5681–5695, https://doi.org/10.5194/amt-13-5681-2020, https://doi.org/10.5194/amt-13-5681-2020, 2020
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The Balloon Lidar Experiment was the first lidar dedicated to measurements in the mesosphere flown on a balloon. During a 6 d flight, it made high-resolution observations of polar mesospheric clouds which form at high latitudes during summer at ~ 83 km altitude and are the highest clouds in Earth's atmosphere. We describe the instrument and assess its performance. We could detect fainter clouds with higher resolution than what is possible with ground-based instruments.
Robert Reichert, Bernd Kaifler, Natalie Kaifler, Markus Rapp, Pierre-Dominique Pautet, Michael J. Taylor, Alexander Kozlovsky, Mark Lester, and Rigel Kivi
Atmos. Meas. Tech., 12, 5997–6015, https://doi.org/10.5194/amt-12-5997-2019, https://doi.org/10.5194/amt-12-5997-2019, 2019
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To determine gravity wave properties like wavelengths, periods and propagation directions at mesospheric altitudes (∼ 86 km) we combine lidar and airglow temperature and meteor radar wind data. By means of wavelet transformation we investigate the wave field and determine intrinsic wave properties as functions of time and period. We are able to identify several gravity wave packets by their distinct propagation and discover a superposition with possible wave–wave and wave–mean-flow interaction.
Markus Rapp, Andreas Dörnbrack, and Bernd Kaifler
Atmos. Meas. Tech., 11, 1031–1048, https://doi.org/10.5194/amt-11-1031-2018, https://doi.org/10.5194/amt-11-1031-2018, 2018
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Temperature profiles from operational weather satellites are used to determine the global distribution of gravity wave activity. This is an important information to constrain global climate models. The quality of this data set is assessed by
systematic comparison to model fields from ECMWF which are considered very high quality. This reveals good agreement between model and observations, albeit the model misses localized centers of wave activity if model resolution is too low.
B. Ehard, B. Kaifler, N. Kaifler, and M. Rapp
Atmos. Meas. Tech., 8, 4645–4655, https://doi.org/10.5194/amt-8-4645-2015, https://doi.org/10.5194/amt-8-4645-2015, 2015
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We evalute four methods currently used for gravity wave extraction from lidar temperature measurements. The spectral response of these methods is determined with the help of synthetic temperature perturbations. Afterwards, the methods are applied to lidar temperature measurements over New Zealand for further evaluation of the four algorithms. Based on the results two methods are recommended for gravity wave extraction.
Jens Fiedler, Gerd Baumgarten, Michael Gerding, Torsten Köpnick, Reik Ostermann, and Bernd Kaifler
EGUsphere, https://doi.org/10.5194/egusphere-2025-1995, https://doi.org/10.5194/egusphere-2025-1995, 2025
This preprint is open for discussion and under review for Geoscientific Instrumentation, Methods and Data Systems (GI).
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We developed a system for frequency control and monitoring of pulsed high-power lasers. It works in real-time, controls the laser cavity length, and performs a spectral analyzes of each individual laser pulse. The motivation for this work was to improve the retrieval of Doppler winds measured by lidar in the middle atmosphere by taking the frequency stability of the lidar transmitter into account.
Natalie Kaifler, Bernd Kaifler, Markus Rapp, Guiping Liu, Diego Janches, Gerd Baumgarten, and Jose-Luis Hormaechea
Atmos. Chem. Phys., 24, 14029–14044, https://doi.org/10.5194/acp-24-14029-2024, https://doi.org/10.5194/acp-24-14029-2024, 2024
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Noctilucent clouds (NLCs) are silvery clouds that can be viewed during twilight and indicate atmospheric conditions like temperature and water vapor in the upper mesosphere. High-resolution measurements from a remote sensing laser instrument provide NLC height, brightness, and occurrence rate since 2017. Most observations occur in the morning hours, likely caused by strong tidal winds, and NLC ice particles are thus transported from elsewhere to the observing location in the Southern Hemisphere.
Robert Reichert, Natalie Kaifler, and Bernd Kaifler
Atmos. Meas. Tech., 17, 4659–4673, https://doi.org/10.5194/amt-17-4659-2024, https://doi.org/10.5194/amt-17-4659-2024, 2024
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Imagine you want to determine how quickly the pitch of a passing ambulance’s siren changes. If the vehicle is traveling slowly, the pitch changes only slightly, but if it is traveling fast, the pitch also changes rapidly. In a similar way, the wind in the middle atmosphere modulates the wavelength of atmospheric gravity waves. We have investigated the question of how strong the maximum wind may be so that the change in wavelength can still be determined with the help of wavelet transformation.
Natalie Kaifler, Bernd Kaifler, Markus Rapp, and David C. Fritts
Atmos. Chem. Phys., 23, 949–961, https://doi.org/10.5194/acp-23-949-2023, https://doi.org/10.5194/acp-23-949-2023, 2023
Short summary
Short summary
We used a lidar to measure polar mesospheric clouds from a balloon floating in the upper stratosphere. The thin-layered ice clouds at 83 km altitude are perturbed by waves. The high-resolution lidar soundings reveal small-scale structures induced by the breaking of those waves. We study these patterns and find that they occur very often. We show their morphology and discuss associated dynamical physical processes, which help to interpret case studies and to guide modelling.
Natalie Kaifler, Bernd Kaifler, Markus Rapp, and David C. Fritts
Earth Syst. Sci. Data, 14, 4923–4934, https://doi.org/10.5194/essd-14-4923-2022, https://doi.org/10.5194/essd-14-4923-2022, 2022
Short summary
Short summary
We measured polar mesospheric clouds (PMCs), our Earth’s highest clouds at the edge of space, with a Rayleigh lidar from a stratospheric balloon. We describe how we derive the cloud’s brightness and discuss the stability of the gondola pointing and the sensitivity of our measurements. We present our high-resolution PMC dataset that is used to study dynamical processes in the upper mesosphere, e.g. regarding gravity waves, mesospheric bores, vortex rings, and Kelvin–Helmholtz instabilities.
Kevin Ohneiser, Albert Ansmann, Bernd Kaifler, Alexandra Chudnovsky, Boris Barja, Daniel A. Knopf, Natalie Kaifler, Holger Baars, Patric Seifert, Diego Villanueva, Cristofer Jimenez, Martin Radenz, Ronny Engelmann, Igor Veselovskii, and Félix Zamorano
Atmos. Chem. Phys., 22, 7417–7442, https://doi.org/10.5194/acp-22-7417-2022, https://doi.org/10.5194/acp-22-7417-2022, 2022
Short summary
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We present and discuss 2 years of long-term lidar observations of the largest stratospheric perturbation by wildfire smoke ever observed. The smoke originated from the record-breaking Australian fires in 2019–2020 and affects climate conditions and even the ozone layer in the Southern Hemisphere. The obvious link between dense smoke occurrence in the stratosphere and strong ozone depletion found in the Arctic and in the Antarctic in 2020 can be regarded as a new aspect of climate change.
Stefanie Knobloch, Bernd Kaifler, and Markus Rapp
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2021-310, https://doi.org/10.5194/amt-2021-310, 2022
Preprint withdrawn
Short summary
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The study tests the quality of temperature measurements from the airborne Rayleigh lidar ALIMA. The ALIMA system was first used during the SouthTRAC campaign in September 2019 in the vicinity of the Southern Andes, Drake Passage and Antarctic Peninsula. The raw lidar measurements are additionally simulated based on reanalysis data for one research flight. Different types of uncertainty influencing the accuracy of the temperature measurements are studied, e.g. atmospheric and technical sources.
Emranul Sarkar, Alexander Kozlovsky, Thomas Ulich, Ilkka Virtanen, Mark Lester, and Bernd Kaifler
Atmos. Meas. Tech., 14, 4157–4169, https://doi.org/10.5194/amt-14-4157-2021, https://doi.org/10.5194/amt-14-4157-2021, 2021
Short summary
Short summary
The biasing effect in meteor radar temperature has been a pressing issue for the last 2 decades. This paper has addressed the underlying reasons for such a biasing effect on both theoretical and experimental grounds. An improved statistical method has been developed which allows atmospheric temperatures at around 90 km to be measured with meteor radar in an independent way such that any subsequent bias correction or calibration is no longer required.
Bernd Kaifler, Dimitry Rempel, Philipp Roßi, Christian Büdenbender, Natalie Kaifler, and Volodymyr Baturkin
Atmos. Meas. Tech., 13, 5681–5695, https://doi.org/10.5194/amt-13-5681-2020, https://doi.org/10.5194/amt-13-5681-2020, 2020
Short summary
Short summary
The Balloon Lidar Experiment was the first lidar dedicated to measurements in the mesosphere flown on a balloon. During a 6 d flight, it made high-resolution observations of polar mesospheric clouds which form at high latitudes during summer at ~ 83 km altitude and are the highest clouds in Earth's atmosphere. We describe the instrument and assess its performance. We could detect fainter clouds with higher resolution than what is possible with ground-based instruments.
Robert Reichert, Bernd Kaifler, Natalie Kaifler, Markus Rapp, Pierre-Dominique Pautet, Michael J. Taylor, Alexander Kozlovsky, Mark Lester, and Rigel Kivi
Atmos. Meas. Tech., 12, 5997–6015, https://doi.org/10.5194/amt-12-5997-2019, https://doi.org/10.5194/amt-12-5997-2019, 2019
Short summary
Short summary
To determine gravity wave properties like wavelengths, periods and propagation directions at mesospheric altitudes (∼ 86 km) we combine lidar and airglow temperature and meteor radar wind data. By means of wavelet transformation we investigate the wave field and determine intrinsic wave properties as functions of time and period. We are able to identify several gravity wave packets by their distinct propagation and discover a superposition with possible wave–wave and wave–mean-flow interaction.
Andreas Dörnbrack, Sonja Gisinger, Natalie Kaifler, Tanja Christina Portele, Martina Bramberger, Markus Rapp, Michael Gerding, Jens Faber, Nedjeljka Žagar, and Damjan Jelić
Atmos. Chem. Phys., 18, 12915–12931, https://doi.org/10.5194/acp-18-12915-2018, https://doi.org/10.5194/acp-18-12915-2018, 2018
Short summary
Short summary
A deep upper-air sounding stimulated the current investigation of internal gravity waves excited during a minor sudden stratospheric warming (SSW) in the Arctic winter 2015/16. The analysis of the radiosonde profile revealed large kinetic and potential energies in the upper stratosphere without any simultaneous enhancement of upper tropospheric and lower stratospheric values. In combination with high-resolution meteorological analyses we identified an elevated source of gravity wave excitation.
Markus Rapp, Andreas Dörnbrack, and Bernd Kaifler
Atmos. Meas. Tech., 11, 1031–1048, https://doi.org/10.5194/amt-11-1031-2018, https://doi.org/10.5194/amt-11-1031-2018, 2018
Short summary
Short summary
Temperature profiles from operational weather satellites are used to determine the global distribution of gravity wave activity. This is an important information to constrain global climate models. The quality of this data set is assessed by
systematic comparison to model fields from ECMWF which are considered very high quality. This reveals good agreement between model and observations, albeit the model misses localized centers of wave activity if model resolution is too low.
B. Ehard, B. Kaifler, N. Kaifler, and M. Rapp
Atmos. Meas. Tech., 8, 4645–4655, https://doi.org/10.5194/amt-8-4645-2015, https://doi.org/10.5194/amt-8-4645-2015, 2015
Short summary
Short summary
We evalute four methods currently used for gravity wave extraction from lidar temperature measurements. The spectral response of these methods is determined with the help of synthetic temperature perturbations. Afterwards, the methods are applied to lidar temperature measurements over New Zealand for further evaluation of the four algorithms. Based on the results two methods are recommended for gravity wave extraction.
T. D. Demissie, P. J. Espy, N. H. Kleinknecht, M. Hatlen, N. Kaifler, and G. Baumgarten
Atmos. Chem. Phys., 14, 12133–12142, https://doi.org/10.5194/acp-14-12133-2014, https://doi.org/10.5194/acp-14-12133-2014, 2014
Short summary
Short summary
Summertime gravity waves detected in noctilucent clouds (NLCs) between 64◦ and 74◦N are found to have a similar climatology to those observed between 60◦ and 64◦N, and their direction of propagation is to the north and northeast as observed south of 64◦N. However, a unique population of fast, short wavelength waves propagating towards the SW is observed in the NLC. The sources of the prominent wave structures observed in the NLC are likely to be from waves propagating from near the tropopause.
Related subject area
Subject: Others (Wind, Precipitation, Temperature, etc.) | Technique: Remote Sensing | Topic: Instruments and Platforms
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The paper aims to study the ground reflection, or clutter, of the signal from a spaceborne radar in the context of ESA's WIVERN (WInd VElocity Radar Nephoscop) mission, which will observe in-cloud winds. Using topography and land type data, with a model of the satellite orbit and rotating antenna, simulations of scans have been run over the Piedmont region of Italy. These measurements cover the full range of the ground clutter over land for WIVERN and have allowed for analyses of the precision and accuracy of velocity observations.
Michael Vaughan, Kevin Ridley, Benjamin Witschas, Oliver Lux, Ines Nikolaus, and Oliver Reitebuch
Atmos. Meas. Tech., 18, 2149–2181, https://doi.org/10.5194/amt-18-2149-2025, https://doi.org/10.5194/amt-18-2149-2025, 2025
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ESA's Aeolus mission, launched in 2018, has exceeded expectations, providing valuable global wind lidar data for nearly 5 years. Its data have improved weather forecasting, with Mie-cloudy winds proving to be especially precise. Challenges have emerged, such as unexpected misalignments in signal angles and reduced signal levels due to beam clipping and laser issues. Lessons from Aeolus highlight the need for better optical alignment and active control systems for future lidar missions.
Claire C. Trop, James LaBelle, Philip J. Erickson, Shun-Rong Zhang, David McGaw, and Terrence Kovacs
Atmos. Meas. Tech., 18, 1909–1925, https://doi.org/10.5194/amt-18-1909-2025, https://doi.org/10.5194/amt-18-1909-2025, 2025
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Traveling ionospheric disturbances (TIDs) are manifestations of atmospheric waves that are significant for the transfer of energy and momentum between atmospheric layers and regions. This work demonstrates that velocities and directions of TIDs can be measured by monitoring the tiny shift in frequency of AM radio signals when they reflect from a moving ionosphere and that this method can be scaled to use large numbers of radio receivers and transmitters to monitor TIDs on a continental scale.
Zishun Qiao, Alan Z. Liu, Gunter Stober, Javier Fuentes, Fabio Vargas, Christian L. Adami, and Iain M. Reid
Atmos. Meas. Tech., 18, 1091–1104, https://doi.org/10.5194/amt-18-1091-2025, https://doi.org/10.5194/amt-18-1091-2025, 2025
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This paper describes the installation of the Chilean Observation Network De Meteor Radars (CONDOR) and its initial results. The routine winds are point-to-point comparable to the co-located lidar winds. The retrievals of spatially resolved horizontal wind fields and vertical winds are also facilitated, benefiting from the extensive meteor detections. The successful deployment and maintenance of CONDOR provide 24/7 and state-of-the-art wind measurements to the research community.
Josemaria Gomez Socola, Fabiano S. Rodrigues, Isaac G. Wright, Igo Paulino, and Ricardo Buriti
Atmos. Meas. Tech., 18, 909–919, https://doi.org/10.5194/amt-18-909-2025, https://doi.org/10.5194/amt-18-909-2025, 2025
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New low-cost, off-the-shelf Global Navigation Satellite System (GNSS) receivers enable the estimation of zonal ionospheric irregularity drifts using the scintillation spaced-receiver technique, previously tested only with commercial GNSS receivers. Despite their low C/No resolution (1 dB-Hz), we demonstrate that the recorded raw data can be used to estimate irregularity drifts. Further, our observations are consistent with the behavior of an empirical model of the thermospheric winds (HMW14).
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The ASSIST is a commercially-available ground-based infrared spectroradiometer. It is designed for automated and passive measurement of the thermal radiation emitted by the atmosphere, providing information about the vertical distribution of temperature and humidity, trace gases, clouds, and aerosols in the boundary layer. In this paper, we outline the key characteristics of the ASSIST hardware and signal processing algorithm that yields downwelling radiance spectra in near real-time.
Junho Ho, Zhe Li, and Guifu Zhang
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This study quantitatively analyzes and compares weather measurements from planar (PPPAR) and cylindrical polarimetric phased-array radars (CPPARs). It examines data quality and potential problems and clarifies misunderstandings between configurations. The findings highlight 2D PPPARs' challenges in making accurate weather measurements when the beam steers off broadside. The CPPAR shows promise in obtaining high-quality polarimetric data due to its azimuthal scan-invariant beam characteristics.
Thibault Boulant, Tomline Michel, and Matthieu Valla
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This paper presents a design of a UV wind lidar, made with a UV fiber laser and a Quadri Mach-Zehnder interferometer as a spectral analyzer, used to measure the wind in front of future low-consumption aircraft. The article details the optimization of the different elements of the instrument with simulations. This paper also presents a method to optimize laser angles for determining wind direction and strength and shows a 50 % improvement over the current angles used.
Joel Rasch, Anders Carlström, Jacob Christensen, and Thomas Liljegren
Atmos. Meas. Tech., 17, 6213–6222, https://doi.org/10.5194/amt-17-6213-2024, https://doi.org/10.5194/amt-17-6213-2024, 2024
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Soon the MetOp Second Generation (Metop-SG) series of polar orbiting meteorological satellites will be launched. On these satellites, the GRAS-2 instrument will be mounted. It will provide GNSS radio occultation measurements with unsurpassed accuracy. The occultation measurements are used routinely for numerical weather prognosis, i.e. predicting the weather. In this paper, we describe the design of this new instrument and the novel methods developed to process the data.
Marek Sommer, Tomáš Czakoj, Iva Ambrožová, Martin Kákona, Olena Velychko, and Ondřej Ploc
EGUsphere, https://doi.org/10.5194/egusphere-2024-2789, https://doi.org/10.5194/egusphere-2024-2789, 2024
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This work studies powerful bursts of radiation, called Terrestrial Gamma Ray Flashes, which happen during thunderstorms. It explores the use of planes and weather balloons as platforms for radiation detectors to gather data about this phenomenon. Using computer simulations, it was found that balloons might work better for high-altitude storms, while planes could be useful for lower ones. Moreover, the influence of the Terrestrial Gamma Ray Flash strength and its altitude of origin was revealed.
Jens Fiedler and Gerd Baumgarten
Atmos. Meas. Tech., 17, 5841–5859, https://doi.org/10.5194/amt-17-5841-2024, https://doi.org/10.5194/amt-17-5841-2024, 2024
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This article describes the current status of a lidar installed at ALOMAR in northern Norway. It has investigated the Arctic middle atmosphere on a climatological basis for 30 years. We discuss major upgrades of the system implemented during recent years, including methods for reliable remote operation of this complex lidar. We also show examples that illustrate the performance of the lidar during measurements at different altitude ranges and timescales.
Jonathan E. Murray, Laura Warwick, Helen Brindley, Alan Last, Patrick Quigley, Andy Rochester, Alexander Dewar, and Daniel Cummins
Atmos. Meas. Tech., 17, 4757–4775, https://doi.org/10.5194/amt-17-4757-2024, https://doi.org/10.5194/amt-17-4757-2024, 2024
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The Far INfrarEd Spectrometer for Surface Emissivity, FINESSE, is designed to measure the ability of natural surfaces to emit infrared radiation. FINESSE combines a commercial instrument with custom-built optics to view a surface from different angles with complementary views of the sky. Its choice of internal components means it can cover a wide range of wavelengths, extending into the far-infrared. We characterize FINESSE’s uncertainty budget and provide examples of its measurement capability.
Cornelius Hald, Maximilian Schaper, Annette Böhm, Michael Frech, Jan Petersen, Bertram Lange, and Benjamin Rohrdantz
Atmos. Meas. Tech., 17, 4695–4707, https://doi.org/10.5194/amt-17-4695-2024, https://doi.org/10.5194/amt-17-4695-2024, 2024
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Weather radars should use lightning protection to be safe from damage, but the rods can reduce the quality of the radar measurements. This study presents three new solutions for lightning protection for weather radars and evaluates their influence on data quality. The results are compared to the current system. All tested ones have very little effect on data, and a new lightning protection system with four rods is recommended for the German Meteorological Service.
Samuel K. Kristoffersen, William E. Ward, and Chris E. Meek
Atmos. Meas. Tech., 17, 3995–4014, https://doi.org/10.5194/amt-17-3995-2024, https://doi.org/10.5194/amt-17-3995-2024, 2024
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In this paper, the relationship between observations from two instruments, a meteor radar and a field-widened Michelson interferometer (ERWIN) which provide complementary information on this region, is investigated. On average the ratio of ERWIN winds to meteor radar winds is ∼ 0.7. Differences between the wind observations may be caused by variations in the airglow brightness associated with dissipating gravity waves.
Qingchen Xu, Iain Murray Reid, Bing Cai, Christian Adami, Zengmao Zhang, Mingliang Zhao, and Wen Li
Atmos. Meas. Tech., 17, 2957–2975, https://doi.org/10.5194/amt-17-2957-2024, https://doi.org/10.5194/amt-17-2957-2024, 2024
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To have better understanding of the dynamics of the lower and middle atmosphere, we installed a newly designed dual-frequency radar system that uses 53.8 MHz for near-ground to 20 km wind measurements and 35.0 MHz for 70 to 100 km wind measurements. The initial results show its good performance, along with the analysis of typical winter gravity wave activities.
Michael Gerding, Robin Wing, Eframir Franco-Diaz, Gerd Baumgarten, Jens Fiedler, Torsten Köpnick, and Reik Ostermann
Atmos. Meas. Tech., 17, 2789–2809, https://doi.org/10.5194/amt-17-2789-2024, https://doi.org/10.5194/amt-17-2789-2024, 2024
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This paper describes a new lidar system developed in Germany intended to study wind and temperature at night in the middle atmosphere. The paper explains how we have set up the system to work automatically and gives technical details for anyone who wants to build a similar system. We present a case study showing temperatures and winds at different altitudes. In a future article, we will present how we process the data and deal with uncertainties.
Jinhong Xian, Chao Lu, Xiaoling Lin, Honglong Yang, Ning Zhang, and Li Zhang
Atmos. Meas. Tech., 17, 1837–1850, https://doi.org/10.5194/amt-17-1837-2024, https://doi.org/10.5194/amt-17-1837-2024, 2024
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Improving the monitoring capability of atmospheric turbulence can help unravel the mystery of turbulence. Based on some assumptions, scientists have proposed various detection methods. However, these assumptions limit their applicability. We abandoned these assumptions and proposed a more accurate method, revealing some new results. Our method can provide more accurate three-dimensional features of turbulence, which will have a huge driving effect on the development of turbulence.
Thorben H. Mense, Josef Höffner, Gerd Baumgarten, Ronald Eixmann, Jan Froh, Alsu Mauer, Alexander Munk, Robin Wing, and Franz-Josef Lübken
Atmos. Meas. Tech., 17, 1665–1677, https://doi.org/10.5194/amt-17-1665-2024, https://doi.org/10.5194/amt-17-1665-2024, 2024
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A novel lidar system with five beams measured horizontal and vertical winds together, reaching altitudes up to 25 km. Developed in Germany, it revealed accurate horizontal wind data compared to forecasts, but vertical wind estimates differed. The lidar's capability to detect small-scale wind patterns was highlighted, advancing atmospheric research.
Peter Dalin, Urban Brändström, Johan Kero, Peter Voelger, Takanori Nishiyama, Trond Trondsen, Devin Wyatt, Craig Unick, Vladimir Perminov, Nikolay Pertsev, and Jonas Hedin
Atmos. Meas. Tech., 17, 1561–1576, https://doi.org/10.5194/amt-17-1561-2024, https://doi.org/10.5194/amt-17-1561-2024, 2024
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A novel infrared imaging instrument (OH imager) was put into operation in November 2022 at the Swedish Institute of Space Physics in Kiruna (Sweden). The OH imager is dedicated to the study of nightglow emissions coming from the hydroxyl (OH) and molecular oxygen (O2) layers in the mesopause (80–100 km). Based on a brightness ratio of two OH emission lines, the neutral temperature is estimated at around 87 km. The average daily winter temperature for the period January–April 2023 is 203±10 K.
Thomas Wagner and Jānis Puķīte
Atmos. Meas. Tech., 17, 277–297, https://doi.org/10.5194/amt-17-277-2024, https://doi.org/10.5194/amt-17-277-2024, 2024
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We present a radiance calibration method based on the comparison of measurements and radiative transfer simulations of the zenith-scattered sun radiance during twilight. Cloud-free conditions are required. The method can be applied to measurements in the filed, and no laboratory measurements are required. The accuracy is estimated to range from about 4 % at 340 nm to about 10 % at 700 nm.
Tobias Böck, Bernhard Pospichal, and Ulrich Löhnert
Atmos. Meas. Tech., 17, 219–233, https://doi.org/10.5194/amt-17-219-2024, https://doi.org/10.5194/amt-17-219-2024, 2024
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In this study, measurement uncertainties from microwave radiometers and their impact on temperature profiling are analyzed. These measurement uncertainties include horizontal inhomogeneities of the atmosphere, pointing errors or tilts of the instrument, physical obstacles which are in the line of sight of the radiometer, and radio frequency interferences. Impacts on temperature profiles from these uncertainties are usually small in real-life scenarios and when obstacles are far enough away.
Philipp Gasch, James Kasic, Oliver Maas, and Zhien Wang
Atmos. Meas. Tech., 16, 5495–5523, https://doi.org/10.5194/amt-16-5495-2023, https://doi.org/10.5194/amt-16-5495-2023, 2023
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This paper rethinks airborne wind measurements and investigates a new design for airborne Doppler lidar systems. Recent advances in lidar technology allow the use of multiple lidar systems with fixed viewing directions instead of a single lidar attached to a scanner. Our simulation results show that the proposed new design offers great potential for both higher accuracy and higher-resolution airborne wind measurements.
Christiane Duscha, Juraj Pálenik, Thomas Spengler, and Joachim Reuder
Atmos. Meas. Tech., 16, 5103–5123, https://doi.org/10.5194/amt-16-5103-2023, https://doi.org/10.5194/amt-16-5103-2023, 2023
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We combine observations from two scanning Doppler lidars to obtain new and unique insights into the dynamic processes inherent to atmospheric convection. The approach complements and enhances conventional methods to probe convection and has the potential to substantially deepen our understanding of this complex process, which is crucial to improving our weather and climate models.
Anna Špačková, Martin Fencl, and Vojtěch Bareš
Atmos. Meas. Tech., 16, 3865–3879, https://doi.org/10.5194/amt-16-3865-2023, https://doi.org/10.5194/amt-16-3865-2023, 2023
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Commercial microwave links as rainfall sensors have been investigated and evaluated in numerous studies with gauge-adjusted radar used for reference for rainfall observations. We evaluate collocated commercial microwave links, which are thus exposed to identical atmospheric conditions. This set-up enables the exploration of inconsistencies in observations of independent sensors using data from a real telecommunication network. The sensors are in agreement and are homogeneous in their behaviour.
Alessandro Battaglia, Filippo Emilio Scarsi, Kamil Mroz, and Anthony Illingworth
Atmos. Meas. Tech., 16, 3283–3297, https://doi.org/10.5194/amt-16-3283-2023, https://doi.org/10.5194/amt-16-3283-2023, 2023
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Some of the new generation of cloud and precipitation spaceborne radars will adopt conical scanning. This will make some of the standard calibration techniques impractical. This work presents a methodology to cross-calibrate radars in orbits by matching the reflectivity probability density function of ice clouds observed by the to-be-calibrated and by the reference radar in quasi-coincident locations. Results show that cross-calibration within 1 dB (26 %) is feasible.
Claudio Belotti, Flavio Barbara, Marco Barucci, Giovanni Bianchini, Francesco D'Amato, Samuele Del Bianco, Gianluca Di Natale, Marco Gai, Alessio Montori, Filippo Pratesi, Markus Rettinger, Christian Rolf, Ralf Sussmann, Thomas Trickl, Silvia Viciani, Hannes Vogelmann, and Luca Palchetti
Atmos. Meas. Tech., 16, 2511–2529, https://doi.org/10.5194/amt-16-2511-2023, https://doi.org/10.5194/amt-16-2511-2023, 2023
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FIRMOS (Far-Infrared Radiation Mobile Observation System) is a spectroradiometer measuring in the far-infrared, developed to support the preparation of the FORUM (Far-infrared Outgoing Radiation Understanding and Monitoring) satellite mission. In this paper, we describe the instrument, its data products, and the results of the comparison with a suite of observations made from a high-altitude site during a field campaign, in winter 2018–2019.
Christopher R. Williams, Joshua Barrio, Paul E. Johnston, Paytsar Muradyan, and Scott E. Giangrande
Atmos. Meas. Tech., 16, 2381–2398, https://doi.org/10.5194/amt-16-2381-2023, https://doi.org/10.5194/amt-16-2381-2023, 2023
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This study uses surface disdrometer observations to calibrate 8 years of 915 MHz radar wind profiler deployed in the central United States in northern Oklahoma. This study had two key findings. First, the radar wind profiler sensitivity decreased approximately 3 to 4 dB/year as the hardware aged. Second, this drift was slow enough that calibration can be performed using 3-month intervals. Calibrated radar wind profiler observations and Python processing code are available on public repositories.
Xin Fang, Feng Li, Lei-lei Sun, and Tao Li
Atmos. Meas. Tech., 16, 2263–2272, https://doi.org/10.5194/amt-16-2263-2023, https://doi.org/10.5194/amt-16-2263-2023, 2023
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We successfully developed the first pseudorandom modulation continuous-wave narrowband sodium lidar (PMCW-NSL) system for simultaneous measurements of the mesopause region's temperature and wind. Based on the innovative decoded technique and algorithm for CW lidar, both the main and residual lights modulated by M-code are used and directed to the atmosphere in the vertical and eastward directions, tilted 20° from the zenith. The PMCW-NSL system can applied to airborne and space-borne purposes.
Dana L. McGuffin, Philip J. Cameron-Smith, Matthew A. Horsley, Brian J. Bauman, Wim De Vries, Denis Healy, Alex Pertica, Chris Shaffer, and Lance M. Simms
Atmos. Meas. Tech., 16, 2129–2144, https://doi.org/10.5194/amt-16-2129-2023, https://doi.org/10.5194/amt-16-2129-2023, 2023
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This work demonstrates the viability of a remote sensing technique using nanosatellites to measure stratospheric temperature. This measurement technique can probe the stratosphere and mesosphere at a fine vertical scale around the globe unlike other high-altitude measurement techniques, which would provide an opportunity to observe atmospheric gravity waves and turbulence. We analyze observations from two satellite platforms to provide a proof of concept and characterize measurement uncertainty.
Benjamin Witschas, Sonja Gisinger, Stephan Rahm, Andreas Dörnbrack, David C. Fritts, and Markus Rapp
Atmos. Meas. Tech., 16, 1087–1101, https://doi.org/10.5194/amt-16-1087-2023, https://doi.org/10.5194/amt-16-1087-2023, 2023
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In this paper, a novel scan technique is applied to an airborne coherent Doppler wind lidar, enabling us to measure the vertical wind speed and the horizontal wind speed along flight direction simultaneously with a horizontal resolution of about 800 m and a vertical resolution of 100 m. The performed observations are valuable for gravity wave characterization as they allow us to calculate the leg-averaged momentum flux profile and, with that, the propagation direction of excited gravity waves.
Kevin J. Nelson, Feiqin Xie, Bryan C. Chan, Ashish Goel, Jonathan Kosh, Tyler G. R. Reid, Corey R. Snyder, and Paul M. Tarantino
Atmos. Meas. Tech., 16, 941–954, https://doi.org/10.5194/amt-16-941-2023, https://doi.org/10.5194/amt-16-941-2023, 2023
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Global Navigation Satellite System (GNSS) radio occultation (RO) remote sensing is effective for atmospheric profiling. The capability of a low-cost and scalable commercial off-the-shelf (COTS) GNSS receiver on board high-altitude balloons is tested in two campaigns. Preliminary results demonstrate high-quality refractivity observations from the COTS RO receiver, which is worth further improvement for dense atmospheric observations over a targeted region.
Jenna Ritvanen, Ewan O'Connor, Dmitri Moisseev, Raisa Lehtinen, Jani Tyynelä, and Ludovic Thobois
Atmos. Meas. Tech., 15, 6507–6519, https://doi.org/10.5194/amt-15-6507-2022, https://doi.org/10.5194/amt-15-6507-2022, 2022
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Doppler lidars and weather radars provide accurate wind measurements, with Doppler lidar usually performing better in dry weather conditions and weather radar performing better when there is precipitation. Operating both instruments together should therefore improve the overall performance. We investigate how well a co-located Doppler lidar and X-band radar perform with respect to various weather conditions, including changes in horizontal visibility, cloud altitude, and precipitation.
Bhupal Shrestha, Jerald A. Brotzge, and Junhong Wang
Atmos. Meas. Tech., 15, 6011–6033, https://doi.org/10.5194/amt-15-6011-2022, https://doi.org/10.5194/amt-15-6011-2022, 2022
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The NYS Mesonet Profiler Network is comprised of 17 profiler sites, each equipped with a Doppler lidar, microwave radiometer, and sun photometer. This study presents a multi-year, multi-station evaluation based on well-defined reference measurements. Results demonstrate robust technologies that can aid real-time weather operations and a network test bed that can be used for further expansion, evaluation, and integration of such technologies at a large scale.
Felix Kelberlau and Jakob Mann
Atmos. Meas. Tech., 15, 5323–5341, https://doi.org/10.5194/amt-15-5323-2022, https://doi.org/10.5194/amt-15-5323-2022, 2022
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Floating lidar systems are used for measuring wind speeds offshore, and their motion influences the measurements. This study describes the motion-induced bias on mean wind speed estimates by simulating the lidar sampling pattern of a moving lidar. An analytic model is used to validate the simulations. The bias is low and depends on amplitude and frequency of motion as well as on wind shear. It has been estimated for the example of the Fugro SEAWATCH wind lidar buoy carrying a ZX 300M lidar.
Alessandro Battaglia, Paolo Martire, Eric Caubet, Laurent Phalippou, Fabrizio Stesina, Pavlos Kollias, and Anthony Illingworth
Atmos. Meas. Tech., 15, 3011–3030, https://doi.org/10.5194/amt-15-3011-2022, https://doi.org/10.5194/amt-15-3011-2022, 2022
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We present an instrument simulator for a new sensor, WIVERN (WInd VElocity Radar Nephoscope), a conically scanning radar payload with Doppler capabilities, recently down-selected as one of the four candidates for the European Space Agency Earth Explorer 11 program. The mission aims at measuring horizontal winds in cloudy areas. The simulator is instrumental in the definition and consolidation of the mission requirements and the evaluation of mission performances.
James B. Duncan Jr., Laura Bianco, Bianca Adler, Tyler Bell, Irina V. Djalalova, Laura Riihimaki, Joseph Sedlar, Elizabeth N. Smith, David D. Turner, Timothy J. Wagner, and James M. Wilczak
Atmos. Meas. Tech., 15, 2479–2502, https://doi.org/10.5194/amt-15-2479-2022, https://doi.org/10.5194/amt-15-2479-2022, 2022
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In this study, several ground-based remote sensing instruments are used to estimate the height of the convective planetary boundary layer, and their performance is compared against independent boundary layer depth estimates obtained from radiosondes launched as part of the CHEESEHEAD19 field campaign. The impact of clouds (particularly boundary layer clouds) on the estimation of the boundary layer depth is also investigated.
Vicki Kelsey, Spencer Riley, and Kenneth Minschwaner
Atmos. Meas. Tech., 15, 1563–1576, https://doi.org/10.5194/amt-15-1563-2022, https://doi.org/10.5194/amt-15-1563-2022, 2022
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In the interior western USA there are distances of hundreds of kilometers between weather balloon launch sites for weather forecasting. Satellite coverage can also be sparse or with poor resolution. Using infrared thermometers, clear-sky temperatures were collected and compared with data from weather balloons. A correlation between clear-sky temperatures and precipitable water measurements from weather balloons was found. This means that citizen scientists can collect data.
Benjamin Witschas, Christian Lemmerz, Oliver Lux, Uwe Marksteiner, Oliver Reitebuch, Fabian Weiler, Frederic Fabre, Alain Dabas, Thomas Flament, Dorit Huber, and Michael Vaughan
Atmos. Meas. Tech., 15, 1465–1489, https://doi.org/10.5194/amt-15-1465-2022, https://doi.org/10.5194/amt-15-1465-2022, 2022
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In August 2018, the ESA launched the first Doppler wind lidar into space. In order to calibrate the instrument and to monitor the overall instrument conditions, instrument spectral registration measurements have been performed with Aeolus on a weekly basis. Based on these measurements, the alignment drift of the Aeolus satellite instrument is estimated by applying tools and mathematical model functions to analyze the spectrometer transmission curves.
Joseph J. Michalsky and Peter W. Kiedron
Atmos. Meas. Tech., 15, 353–364, https://doi.org/10.5194/amt-15-353-2022, https://doi.org/10.5194/amt-15-353-2022, 2022
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This paper describes an instrument that measures spectrally from 360 nm (ultraviolet) to 1070 nm (near-infrared) at 1002 separate wavelengths. The measurements were made every minute from the late summer of 2009 to the winter of 2014 at a site in northern Oklahoma (USA; 36.605° N, 97.486° W). Methods are described that enable the normalized transmission across the spectrum to be measured and, subsequently, used to calculate the aerosol optical depth and spectra irradiance.
Julien Totems, Patrick Chazette, and Alexandre Baron
Atmos. Meas. Tech., 14, 7525–7544, https://doi.org/10.5194/amt-14-7525-2021, https://doi.org/10.5194/amt-14-7525-2021, 2021
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We describe in detail the design and calibration of the new Raman channels for the WALI system, going over the important sources of bias and uncertainty on retrieved temperature profiles. For the first time, their impact is investigated using horizontal shots in a homogenous atmosphere: the magnitude of the highlighted biases can be much larger than the targeted absolute accuracy of 1° C. Actual measurement errors are quantified using radiosoundings launched close to the lidar site.
René Sedlak, Patrick Hannawald, Carsten Schmidt, Sabine Wüst, Michael Bittner, and Samo Stanič
Atmos. Meas. Tech., 14, 6821–6833, https://doi.org/10.5194/amt-14-6821-2021, https://doi.org/10.5194/amt-14-6821-2021, 2021
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High-resolution images of the OH* airglow layer (ca. 87 km height) acquired at Otlica Observatory, Slovenia, have been analysed. A statistical analysis of small-scale wave structures with horizontal wavelengths up to 4.5 km suggests strong presence of instability features in the upper mesosphere or lower thermosphere. The dissipated energy of breaking gravity waves is derived from observations of turbulent vortices. It is concluded that dynamical heating plays a vital role in the atmosphere.
Oliver Lux, Christian Lemmerz, Fabian Weiler, Thomas Kanitz, Denny Wernham, Gonçalo Rodrigues, Andrew Hyslop, Olivier Lecrenier, Phil McGoldrick, Frédéric Fabre, Paolo Bravetti, Tommaso Parrinello, and Oliver Reitebuch
Atmos. Meas. Tech., 14, 6305–6333, https://doi.org/10.5194/amt-14-6305-2021, https://doi.org/10.5194/amt-14-6305-2021, 2021
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The work assesses the frequency stability of the laser transmitters on board Aeolus and discusses its influence on the quality of the global wind data. Excellent frequency stability of the space lasers is evident, although enhanced frequency noise occurs at certain locations along the orbit due to micro-vibrations that are introduced by the satellite’s reaction wheels. The study elaborates on this finding and investigates the extent to which the enhanced frequency noise increases the wind error.
Tingyu Yan, Jeffery A. Langille, William E. Ward, William A. Gault, Alan Scott, Andrew Bell, Driss Touahiri, Sheng-Hai Zheng, and Chunmin Zhang
Atmos. Meas. Tech., 14, 6213–6232, https://doi.org/10.5194/amt-14-6213-2021, https://doi.org/10.5194/amt-14-6213-2021, 2021
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High-resolution interferometers are routinely used to measure upper atmospheric motions by measuring small Doppler shifts in spectrally isolated airglow emissions. The birefringent interferometer presented in this paper has similar capabilities as several existing state-of-the-art instruments but is smaller and less complex to construct and operate. This paper presents the measurement technique and characterization of a lab prototype and examines the performance of the instrument.
Etienne Cheynet, Martin Flügge, Joachim Reuder, Jasna B. Jakobsen, Yngve Heggelund, Benny Svardal, Pablo Saavedra Garfias, Charlotte Obhrai, Nicolò Daniotti, Jarle Berge, Christiane Duscha, Norman Wildmann, Ingrid H. Onarheim, and Marte Godvik
Atmos. Meas. Tech., 14, 6137–6157, https://doi.org/10.5194/amt-14-6137-2021, https://doi.org/10.5194/amt-14-6137-2021, 2021
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The COTUR campaign explored the structure of wind turbulence above the ocean to improve the design of future multi-megawatt offshore wind turbines. Deploying scientific instruments offshore is both a financial and technological challenge. Therefore, lidar technology was used to remotely measure the wind above the ocean from instruments located on the seaside. The experimental setup is tailored to the study of the spatial correlation of wind gusts, which governs the wind loading on structures.
Fabian Weiler, Thomas Kanitz, Denny Wernham, Michael Rennie, Dorit Huber, Marc Schillinger, Olivier Saint-Pe, Ray Bell, Tommaso Parrinello, and Oliver Reitebuch
Atmos. Meas. Tech., 14, 5153–5177, https://doi.org/10.5194/amt-14-5153-2021, https://doi.org/10.5194/amt-14-5153-2021, 2021
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This paper reports on dark current signal anomalies of the detectors used on board the ESA's Earth Explorer satellite Aeolus during the first 1.5 years in orbit. After introducing sophisticated algorithms to classify dark current anomalies according to their characteristics, the impact of the different kinds of anomalies on wind measurements is discussed. In addition, mitigation approaches for the wind retrieval are presented and potential root causes are discussed.
Chuanliang Zhang, Xuejin Sun, Wen Lu, Yingni Shi, Naiying Dou, and Shaohui Li
Atmos. Meas. Tech., 14, 4787–4803, https://doi.org/10.5194/amt-14-4787-2021, https://doi.org/10.5194/amt-14-4787-2021, 2021
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The first spaceborne doppler wind lidar (DWL) Aeolus operates on sun-synchronous dawn–dusk orbit to lower the impact of solar background radiation (SBR) on wind observation accuracy. Increased SBR leads to an increment of averaged wind observation uncertainties from 0.19 to 0.27 m s-1 comparing Aeolus and two added spaceborne DWLs operating on orbits with local ascending times of 15:00 and 12:00 LT. A quantitative design of laser pulse energy according to accuracy requirements is also proposed.
Didier Bruneau and Jacques Pelon
Atmos. Meas. Tech., 14, 4375–4402, https://doi.org/10.5194/amt-14-4375-2021, https://doi.org/10.5194/amt-14-4375-2021, 2021
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Taking advantage of Aeolus success and of our airborne lidar system expertise, we present a new spaceborne wind lidar design for operational Aeolus follow-on missions, keeping most of the initial lidar system but relying on a single Mach–Zehnder interferometer to relax operational constraints and reduce measurement bias. System parameters are optimized. Random and systematic errors are shown to be compliant with the initial mission requirements. In addition, the system allows unbiased retrieval.
Franz-Josef Lübken and Josef Höffner
Atmos. Meas. Tech., 14, 3815–3836, https://doi.org/10.5194/amt-14-3815-2021, https://doi.org/10.5194/amt-14-3815-2021, 2021
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We present a new concept for a cluster of lidars that allows us to measure time-resolved profiles of temperatures, winds, and aerosols in the entire middle atmosphere for the first time, also covering regional horizontal scales (
four-dimensional coverage). Measurements are performed during day and night. The essential component is a newly developed laser with unprecedented performance. We present the first measurements. New observational capabilities in atmospheric physics are established.
Mareike Heckl, Andreas Fix, Matthias Jirousek, Franz Schreier, Jian Xu, and Markus Rapp
Atmos. Meas. Tech., 14, 1689–1713, https://doi.org/10.5194/amt-14-1689-2021, https://doi.org/10.5194/amt-14-1689-2021, 2021
William Thielicke, Waldemar Hübert, Ulrich Müller, Michael Eggert, and Paul Wilhelm
Atmos. Meas. Tech., 14, 1303–1318, https://doi.org/10.5194/amt-14-1303-2021, https://doi.org/10.5194/amt-14-1303-2021, 2021
Short summary
Short summary
We developed a wind-measuring drone with exceptional measuring accuracy and a very long flight time. Measurements are extensively validated at different levels. A comparison with a bistatic lidar reveals very small bias and RMSEs. We also present a demonstration measurement in the wake of a wind turbine. We think that our solution is a significant enhancement to existing designs, and other researchers can benefit from the details that we are giving in the paper.
Cited articles
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Short summary
This paper describes the Compact Rayleigh Autonomous Lidar (CORAL), which is the first lidar instrument to make fully automatic high-resolution measurements of atmospheric density and temperature between 15 and 90 km altitude. CORAL achieves a much larger measurement cadence than conventional lidars and thus facilitates studies of rare atmospheric phenomena.
This paper describes the Compact Rayleigh Autonomous Lidar (CORAL), which is the first lidar...
