Articles | Volume 17, issue 15
https://doi.org/10.5194/amt-17-4695-2024
© Author(s) 2024. 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-17-4695-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
13 Aug 2024
Research article |
| 13 Aug 2024
| 13 Aug 2024
Evaluation of the effects of different lightning protection rods on the data quality of C-band weather radars
Cornelius Hald
CORRESPONDING AUTHOR
Observatorium Hohenpeißenberg, Forschung und Entwicklung, Deutscher Wetterdienst, Albin-Schwaiger-Weg 10, 82383 Hohenpeißenberg, Germany
Maximilian Schaper
Observatorium Hohenpeißenberg, Forschung und Entwicklung, Deutscher Wetterdienst, Albin-Schwaiger-Weg 10, 82383 Hohenpeißenberg, Germany
Annette Böhm
Observatorium Hohenpeißenberg, Forschung und Entwicklung, Deutscher Wetterdienst, Albin-Schwaiger-Weg 10, 82383 Hohenpeißenberg, Germany
Michael Frech
Observatorium Hohenpeißenberg, Forschung und Entwicklung, Deutscher Wetterdienst, Albin-Schwaiger-Weg 10, 82383 Hohenpeißenberg, Germany
Jan Petersen
Technische Infrastruktur und Betrieb, Deutscher Wetterdienst, Frahmredder 95, 22393 Hamburg, Germany
Bertram Lange
Technische Infrastruktur und Betrieb, Deutscher Wetterdienst, Frahmredder 95, 22393 Hamburg, Germany
Benjamin Rohrdantz
Technische Infrastruktur und Betrieb, Deutscher Wetterdienst, Frahmredder 95, 22393 Hamburg, Germany
Related authors
Michael Frech, Cornelius Hald, Maximilian Schaper, Bertram Lange, and Benjamin Rohrdantz
Atmos. Meas. Tech., 16, 295–309, https://doi.org/10.5194/amt-16-295-2023, https://doi.org/10.5194/amt-16-295-2023, 2023
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Weather radar data are the backbone of a lot of meteorological products. In order to obtain a better low-level coverage with radar data, additional systems have to be included. The frequency range in which radars are allowed to operate is limited. A potential radar-to-radar interference has to be avoided. The paper derives guidelines on how additional radars can be included into a C-band weather radar network and how interferences can be avoided.
Maximilian Schaper, Michael Frech, David Michaelis, Cornelius Hald, and Benjamin Rohrdantz
Atmos. Meas. Tech., 15, 6625–6642, https://doi.org/10.5194/amt-15-6625-2022, https://doi.org/10.5194/amt-15-6625-2022, 2022
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C-band weather radar data are commonly compromised by radio frequency interference (RFI) from external sources. It is not possible to separate a superimposed interference signal from the radar data. Therefore, the best course of action is to shut down RFI sources as quickly as possible. An automated RFI detection algorithm has been developed. Since its implementation, persistent RFI sources are eliminated much more quickly, while the number of short-lived RFI sources keeps steadily increasing.
Alexander Myagkov, Tatiana Nomokonova, and Michael Frech
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-143, https://doi.org/10.5194/amt-2024-143, 2024
Revised manuscript accepted for AMT
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The study examines the use of the spheroidal shape approximation for calculating cloud radar observables in rain and identifies some limitations. To address these, it introduces the empirical scattering model (EMS) based on high-quality Doppler spectra from a 94 GHz radar. The ESM offers improved accuracy and directly incorporates natural rain's microphysical effects. This new model can enhance retrieval and calibration methods, benefiting cloud radar polarimetry experts and scattering modelers.
Michael Frech, Cornelius Hald, Maximilian Schaper, Bertram Lange, and Benjamin Rohrdantz
Atmos. Meas. Tech., 16, 295–309, https://doi.org/10.5194/amt-16-295-2023, https://doi.org/10.5194/amt-16-295-2023, 2023
Short summary
Short summary
Weather radar data are the backbone of a lot of meteorological products. In order to obtain a better low-level coverage with radar data, additional systems have to be included. The frequency range in which radars are allowed to operate is limited. A potential radar-to-radar interference has to be avoided. The paper derives guidelines on how additional radars can be included into a C-band weather radar network and how interferences can be avoided.
Mathias Gergely, Maximilian Schaper, Matthias Toussaint, and Michael Frech
Atmos. Meas. Tech., 15, 7315–7335, https://doi.org/10.5194/amt-15-7315-2022, https://doi.org/10.5194/amt-15-7315-2022, 2022
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This study presents the new vertically pointing birdbath scan of the German C-band radar network, which provides high-resolution profiles of precipitating clouds above all DWD weather radars since the spring of 2021. Our AI-based postprocessing method for filtering and analyzing the recorded radar data offers a unique quantitative view into a wide range of precipitation events from snowfall over stratiform rain to intense frontal showers and will be used to complement DWD's operational services.
Maximilian Schaper, Michael Frech, David Michaelis, Cornelius Hald, and Benjamin Rohrdantz
Atmos. Meas. Tech., 15, 6625–6642, https://doi.org/10.5194/amt-15-6625-2022, https://doi.org/10.5194/amt-15-6625-2022, 2022
Short summary
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C-band weather radar data are commonly compromised by radio frequency interference (RFI) from external sources. It is not possible to separate a superimposed interference signal from the radar data. Therefore, the best course of action is to shut down RFI sources as quickly as possible. An automated RFI detection algorithm has been developed. Since its implementation, persistent RFI sources are eliminated much more quickly, while the number of short-lived RFI sources keeps steadily increasing.
Silke Trömel, Clemens Simmer, Ulrich Blahak, Armin Blanke, Sabine Doktorowski, Florian Ewald, Michael Frech, Mathias Gergely, Martin Hagen, Tijana Janjic, Heike Kalesse-Los, Stefan Kneifel, Christoph Knote, Jana Mendrok, Manuel Moser, Gregor Köcher, Kai Mühlbauer, Alexander Myagkov, Velibor Pejcic, Patric Seifert, Prabhakar Shrestha, Audrey Teisseire, Leonie von Terzi, Eleni Tetoni, Teresa Vogl, Christiane Voigt, Yuefei Zeng, Tobias Zinner, and Johannes Quaas
Atmos. Chem. Phys., 21, 17291–17314, https://doi.org/10.5194/acp-21-17291-2021, https://doi.org/10.5194/acp-21-17291-2021, 2021
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The article introduces the ACP readership to ongoing research in Germany on cloud- and precipitation-related process information inherent in polarimetric radar measurements, outlines pathways to inform atmospheric models with radar-based information, and points to remaining challenges towards an improved fusion of radar polarimetry and atmospheric modelling.
Michael Frech and John Hubbert
Atmos. Meas. Tech., 13, 1051–1069, https://doi.org/10.5194/amt-13-1051-2020, https://doi.org/10.5194/amt-13-1051-2020, 2020
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The prime source of the temperature sensitivity of ZDR can be attributed to the antenna assembly. This result is based on over 2000 solar box scans. These data also reveal that there is a 0.6 dB decrease in gain for a 10 °C temperature increase, which directly relates to a bias of the radar reflectivity factor Z, which has not been not accounted for previously. The ZDR variability in and ZDR calibration performance of the German weather radar network are shown.
M. Frech and J. Steinert
Hydrol. Earth Syst. Sci., 19, 1141–1152, https://doi.org/10.5194/hess-19-1141-2015, https://doi.org/10.5194/hess-19-1141-2015, 2015
Related subject area
Subject: Others (Wind, Precipitation, Temperature, etc.) | Technique: Remote Sensing | Topic: Instruments and Platforms
Quantitative error analysis of polarimetric phased-array radar weather measurements to reveal radar performance and configuration potential
Spectral performance analysis of the Fizeau interferometer onboard ESA's Aeolus wind lidar satellite
Optimization of a direct-detection UV wind lidar architecture for 3D wind reconstruction at high altitude
The GRAS-2 radio occultation mission
The ALOMAR Rayleigh/Mie/Raman lidar: status after 30 years of operation
Chilean Observation Network De MeteOr Radars (CONDOR): Multi-Static System Configuration & Wind Comparison with Co-located Lidar
Tracking Traveling Ionospheric Disturbances through Doppler-shifted AM radio transmissions
The Far-INfrarEd Spectrometer for Surface Emissivity (FINESSE) – Part 1: Instrument description and level 1 radiances
ScintPi measurements of low-latitude ionospheric irregularity drifts using the spaced-receiver technique and SBAS signals
Wind comparisons between meteor radar and Doppler shifts in airglow emissions using field-widened Michelson interferometers
A new dual-frequency stratospheric–tropospheric and meteor radar: system description and first results
The Doppler wind, temperature, and aerosol RMR lidar system at Kühlungsborn, Germany – Part 1: Technical specifications and capabilities
Directly measuring the power-law exponent and kinetic energy of atmospheric turbulence using coherent Doppler wind lidar
3D wind observations with a compact mobile lidar based on tropo- and stratospheric aerosol backscatter
A novel infrared imager for studies of hydroxyl and oxygen nightglow emissions in the mesopause above northern Scandinavia
Absolute radiance calibration in the UV and visible spectral range using atmospheric observations during twilight
Measurement uncertainties of scanning microwave radiometers and their influence on temperature profiling
Advancing airborne Doppler lidar wind profiling in turbulent boundary layer flow – an LES-based optimization of traditional scanning-beam versus novel fixed-beam measurement systems
Observing atmospheric convection with dual-scanning lidars
Evaluation of error components in rainfall retrieval from collocated commercial microwave links
In-orbit cross-calibration of millimeter conically scanning spaceborne radars
The Far-Infrared Radiation Mobile Observation System (FIRMOS) for spectral characterization of the atmospheric emission
Calibrating radar wind profiler reflectivity factor using surface disdrometer observations
Pseudorandom modulation continuous-wave narrowband sodium temperature and wind lidar
Stratospheric temperature measurements from nanosatellite stellar occultation observations of refractive bending
Airborne coherent wind lidar measurements of the momentum flux profile from orographically induced gravity waves
GNSS radio occultation soundings from commercial off-the-shelf receivers on board balloon platforms
Complementarity of wind measurements from co-located X-band weather radar and Doppler lidar
Evaluation of the New York State Mesonet Profiler Network data
Quantification of motion-induced measurement error on floating lidar systems
Observation error analysis for the WInd VElocity Radar Nephoscope W-band Doppler conically scanning spaceborne radar via end-to-end simulations
Evaluating convective planetary boundary layer height estimations resolved by both active and passive remote sensing instruments during the CHEESEHEAD19 field campaign
Atmospheric precipitable water vapor and its correlation with clear-sky infrared temperature observations
Spectral performance analysis of the Aeolus Fabry–Pérot and Fizeau interferometers during the first years of operation
Moderate spectral resolution solar irradiance measurements, aerosol optical depth, and solar transmission, from 360 to 1070 nm, using the refurbished rotating shadow band spectroradiometer (RSS)
Mitigation of bias sources for atmospheric temperature and humidity in the mobile Raman Weather and Aerosol Lidar (WALI)
Gravity wave instability structures and turbulence from more than 1.5 years of OH* airglow imager observations in Slovenia
ALADIN laser frequency stability and its impact on the Aeolus wind error
A compact static birefringent interferometer for the measurement of upper atmospheric winds: concept, design and lab performance
The COTUR project: remote sensing of offshore turbulence for wind energy application
Characterization of dark current signal measurements of the ACCDs used on board the Aeolus satellite
Relationship between wind observation accuracy and the ascending node of the sun-synchronous orbit for the Aeolus-type spaceborne Doppler wind lidar
A new lidar design for operational atmospheric wind and cloud/aerosol survey from space
VAHCOLI, a new concept for lidars: technical setup, science applications, and first measurements
A Compact Rayleigh Autonomous Lidar (CORAL) for the middle atmosphere
Measurement characteristics of an airborne microwave temperature profiler (MTP)
Towards accurate and practical drone-based wind measurements with an ultrasonic anemometer
Atmospheric observations with E-band microwave links – challenges and opportunities
Tomographic retrieval algorithm of OH concentration profiles using double spatial heterodyne spectrometers
Wuhan MST radar: technical features and validation of wind observations
Junho Ho, Zhe Li, and Guifu Zhang
Atmos. Meas. Tech., 18, 619–638, https://doi.org/10.5194/amt-18-619-2025, https://doi.org/10.5194/amt-18-619-2025, 2025
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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.
Michael Vaughan, Kevin Ridley, Benjamin Witschas, Oliver Lux, Ines Nikolaus, and Oliver Reitebuch
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-202, https://doi.org/10.5194/amt-2024-202, 2024
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ESAs Aeolus mission, launched in 2018, has exceeded expectations, providing valuable global wind lidar data for nearly five years. Its data has improved weather forecasting, with Mie-cloudy winds proving especially precise. Challenges 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.
Thibault Boulant, Tomline Michel, and Matthieu Valla
Atmos. Meas. Tech., 17, 7049–7064, https://doi.org/10.5194/amt-17-7049-2024, https://doi.org/10.5194/amt-17-7049-2024, 2024
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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.
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.
Zishun Qiao, Alan Z. Liu, Gunter Stober, Javier Fuentes, Fabio Vargas, Christian L. Adami, and Iain M. Reid
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-126, https://doi.org/10.5194/amt-2024-126, 2024
Revised manuscript accepted for AMT
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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, vertical winds, and temperatures 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.
Claire Trop, James LaBelle, Philip Erickson, Shun-Rong Zhang, David McGaw, and Terrence Kovacs
EGUsphere, https://doi.org/10.5194/egusphere-2024-2383, https://doi.org/10.5194/egusphere-2024-2383, 2024
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Traveling Ionospheric Disturbances (TIDs) are manifestations of atmospheric waves that are significant for 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.
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.
Josemaria Gomez Socola, Fabiano Rodrigues, Isaac Wrigth, Igo Paulino, and Ricardo Buriti
EGUsphere, https://doi.org/10.5194/egusphere-2024-2262, https://doi.org/10.5194/egusphere-2024-2262, 2024
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New low-cost, off-the-shelf GNSS receivers enable the estimation of zonal ionospheric irregularity drifts using the "scintillation spaced receiver" technique, which was previously tested only with commercial GNSS receivers. Despite their low C/No resolution (1 dB-Hz), we demonstrate that the raw data obtained from the receivers can be used to estimate irregularity velocities. Furthermore, our observations are consistent with the behavior of an empirical model of the thermospheric winds.
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.
Bernd Kaifler and Natalie Kaifler
Atmos. Meas. Tech., 14, 1715–1732, https://doi.org/10.5194/amt-14-1715-2021, https://doi.org/10.5194/amt-14-1715-2021, 2021
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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.
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
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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.
Martin Fencl, Michal Dohnal, Pavel Valtr, Martin Grabner, and Vojtěch Bareš
Atmos. Meas. Tech., 13, 6559–6578, https://doi.org/10.5194/amt-13-6559-2020, https://doi.org/10.5194/amt-13-6559-2020, 2020
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Commercial microwave links operating at E-band frequencies are increasingly being updated and are frequently replacing older infrastructure. We show that E-band microwave links are able to observe even light rainfalls, a feat practically impossible to achieve by older 15–40 GHz devices. Furthermore, water vapor retrieval may be possible from long E-band microwave links, although the efficient separation of gaseous attenuation from other signal losses will be challenging in practice.
Yuan An, Jinji Ma, Yibo Gao, Wei Xiong, and Xianhua Wang
Atmos. Meas. Tech., 13, 6521–6542, https://doi.org/10.5194/amt-13-6521-2020, https://doi.org/10.5194/amt-13-6521-2020, 2020
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The hydroxyl radical (OH) plays a significant role in atmospheric chemical and physical reactions. The superiority and feasibility of a new satellite sensor, which consists of two spatial heterodyne spectrometers in the orthogonal layout to monitor OH in the middle and upper atmosphere, is proved by the forward model. An inversion algorithm to obtain OH concentrations based on the simulated observation data of sensors and the errors in results are also given.
Lei Qiao, Gang Chen, Shaodong Zhang, Qi Yao, Wanlin Gong, Mingkun Su, Feilong Chen, Erxiao Liu, Weifan Zhang, Huangyuan Zeng, Xuesi Cai, Huina Song, Huan Zhang, and Liangliang Zhang
Atmos. Meas. Tech., 13, 5697–5713, https://doi.org/10.5194/amt-13-5697-2020, https://doi.org/10.5194/amt-13-5697-2020, 2020
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Short summary
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.
Weather radars should use lightning protection to be safe from damage, but the rods can reduce...
