Articles | Volume 10, issue 1
Research article 03 Jan 2017
Research article | 03 Jan 2017
Open-loop GPS signal tracking at low elevation angles from a ground-based observation site
Georg Beyerle and Florian Zus
F. Zus, G. Beyerle, S. Heise, T. Schmidt, and J. Wickert
Atmos. Meas. Tech. Discuss.,
Benjamin Männel, Florian Zus, Galina Dick, Susanne Glaser, Maximilian Semmling, Kyriakos Balidakis, Jens Wickert, Marion Maturilli, Sandro Dahlke, and Harald Schuh
Atmos. Meas. Tech. Discuss.,
Preprint under review for AMTShort summary
Within the MOSAiC expedition, GNSS was used to monitor variations in atmospheric water vapor. Based on 15 months of continuously tracked data, coordinates and hourly zenith total delays (ZTD) were determined using kinematic precise point positioning. The derived ZTD values agree within few millimeters to ERA5 and terrestrial GNSS and VLBI stations. The derived integrated water vapor corresponds to the frequently launched radiosondes (0.08 ± 0.04 kg m−2, RMS of the differences 1.47 kg m−2).
Michal Kačmařík, Jan Douša, Florian Zus, Pavel Václavovic, Kyriakos Balidakis, Galina Dick, and Jens Wickert
Ann. Geophys., 37, 429–446,Short summary
We provide an analysis of processing setting impacts on tropospheric gradients estimated from GNSS observation processing. These tropospheric gradients are related to water vapour distribution in the troposphere and therefore can be helpful in meteorological applications.
Michal Kačmařík, Jan Douša, Galina Dick, Florian Zus, Hugues Brenot, Gregor Möller, Eric Pottiaux, Jan Kapłon, Paweł Hordyniec, Pavel Václavovic, and Laurent Morel
Atmos. Meas. Tech., 10, 2183–2208,
Cuixian Lu, Florian Zus, Maorong Ge, Robert Heinkelmann, Galina Dick, Jens Wickert, and Harald Schuh
Atmos. Meas. Tech., 9, 5965–5973,Short summary
The recent dramatic development of multi-GNSS constellations brings great opportunities and potential for more enhanced precise positioning, navigation, timing, and other applications. In this contribution, we develop a numerical weather model (NWM) constrained PPP processing system to improve the multi-GNSS precise positioning. Compared to the standard PPP solution, significant improvements of both convergence time and positioning accuracy are achieved with the NWM-constrained PPP solution.
Jan Douša, Galina Dick, Michal Kačmařík, Radmila Brožková, Florian Zus, Hugues Brenot, Anastasia Stoycheva, Gregor Möller, and Jan Kaplon
Atmos. Meas. Tech., 9, 2989–3008,Short summary
GNSS products provide observations of atmospheric water vapour. Advanced tropospheric products focus on ultra-fast and high-resolution zenith total delays (ZTDs), horizontal gradients and slant delays, all suitable for rapid-cycle numerical weather prediction (NWP) and severe weather event monitoring. The GNSS4SWEC Benchmark provides a complex data set for developing and assessing these products, with initial focus on reference ZTDs and gradients derived from several NWP and dense GNSS networks.
F. Zus, G. Beyerle, S. Heise, T. Schmidt, and J. Wickert
Atmos. Meas. Tech. Discuss.,
Related subject area
Subject: Others (Wind, Precipitation, Temperature, etc.) | Technique: Remote Sensing | Topic: Instruments and PlatformsA Compact Rayleigh Autonomous Lidar (CORAL) for the middle atmosphereMeasurement characteristics of an airborne microwave temperature profiler (MTP)Towards accurate and practical drone-based wind measurements with an ultrasonic anemometerVAHCOLI, a new concept for lidars: technical setup, science applications, and ﬁrst measurementsAtmospheric observations with E-band microwave links – challenges and opportunitiesTomographic retrieval algorithm of OH concentration profiles using double spatial heterodyne spectrometersWuhan MST radar: technical features and validation of wind observationsJoint analysis of convective structure from the APR-2 precipitation radar and the DAWN Doppler wind lidar during the 2017 Convective Processes Experiment (CPEX)On the relationship between wind observation accuracy and the ascending node of sun-synchronous orbit for the Aeolus-type spaceborne Doppler wind lidarFirst observations of the McMurdo–South Pole oblique ionospheric HF channelVertical wind profiling from the troposphere to the lower mesosphere based on high-resolution heterodyne near-infrared spectroradiometryEffect of OH emission on the temperature and wind measurements derived from limb-viewing observations of the 1.27 µm O2 dayglowDoppler lidar at Observatoire de Haute-Provence for wind profiling up to 75 km altitude: performance evaluation and observationsQuantifying hail size distributions from the sky – application of drone aerial photogrammetryWind sensing with drone-mounted wind lidars: proof of conceptSAETTA: high-resolution 3-D mapping of the total lightning activity in the Mediterranean Basin over Corsica, with a focus on a mesoscale convective system eventApplication of parametric speakers to radio acoustic sounding systemSimulating precipitation radar observations from a geostationary satelliteNovel specular meteor radar systems using coherent MIMO techniques to study the mesosphere and lower thermosphereDual-wavelength radar technique development for snow rate estimation: a case study from GCPExA Fourier transform spectroradiometer for ground-based remote sensing of the atmospheric downwelling long-wave radianceAutomated compact mobile Raman lidar for water vapor measurement: instrument description and validation by comparison with radiosonde, GNSS, and high-resolution objective analysisImplementation of polarization diversity pulse-pair technique using airborne W-band radarMetrology of solar spectral irradiance at the top of the atmosphere in the near infrared measured at Mauna Loa Observatory: the PYR-ILIOS campaignDoppler W-band polarization diversity space-borne radar simulator for wind studiesThe FengYun-3C radio occultation sounder GNOS: a review of the mission and its early results and science applicationsWIRA-C: a compact 142-GHz-radiometer for continuous middle-atmospheric wind measurementsA large-area blackbody for in-flight calibration of an infrared interferometer deployed on board a long-duration balloon for stratospheric researchA measurement campaign to assess sources of error in microwave link rainfall estimationSimulation study for the Stratospheric Inferred Winds (SIW) sub-millimeter limb sounderReduction in 317–780 nm radiance reflected from the sunlit Earth during the eclipse of 21 August 2017A highly miniaturized satellite payload based on a spatial heterodyne spectrometer for atmospheric temperature measurements in the mesosphere and lower thermosphereWind turbine wake measurements with automatically adjusting scanning trajectories in a multi-Doppler lidar setupAirborne wind lidar observations over the North Atlantic in 2016 for the pre-launch validation of the satellite mission AeolusShipborne Wind Measurement and Motion-induced Error Correction of a Coherent Doppler Lidar over the Yellow Sea in 2014In-flight calibration of SCIAMACHY's polarization sensitivityNoise performance of microwave humidity sounders over their lifetimeTemperature dependence of the Brewer global UV measurementsThe effect of cloud liquid water on tropospheric temperature retrievals from microwave measurementsPerdigão 2015: methodology for atmospheric multi-Doppler lidar experimentsStudy and mitigation of calibration factor instabilities in a water vapor Raman lidarImproved pointing information for SCIAMACHY from in-flight measurements of the viewing directions towards sun and moonForest Fire Finder – DOAS application to long-range forest fire detectionIn-flight performance of the Ozone Monitoring InstrumentA comparison of vertical velocity variance measurements from wind profiling radars and sonic anemometersField-of-view characteristics and resolution matching for the Global Precipitation Measurement (GPM) Microwave Imager (GMI)High-resolution observations of small-scale gravity waves and turbulence features in the OH airglow layerAn integrated approach to monitoring the calibration stability of operational dual-polarization radarsSimultaneous and co-located wind measurements in the middle atmosphere by lidar and rocket-borne techniquesMesospheric temperature soundings with the new, daylight-capable IAP RMR lidar
Bernd Kaifler and Natalie Kaifler
Atmos. Meas. Tech., 14, 1715–1732,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.
Mareike Heckl, Andreas Fix, Matthias Jirousek, Franz Schreier, Jian Xu, and Markus Rapp
Atmos. Meas. Tech., 14, 1689–1713,
William Thielicke, Waldemar Hübert, Ulrich Müller, Michael Eggert, and Paul Wilhelm
Atmos. Meas. Tech., 14, 1303–1318,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.
Franz-Josef Lübken and Josef Höffner
Atmos. Meas. Tech. Discuss.,
Revised manuscript accepted for AMTShort summary
We present a new concept for a cluster of lidars which allows for the first time to measure time-resolved profiles of temperatures, winds, and aerosols in the entire middle atmosphere, also covering regional horizontal scales (
four-dimensional coverage). Measurements are performed during day and night. The essential component is newly developed laser with unprecedented performance. We also present first measurements. New observational capabilities in atmospheric physics are established.
Martin Fencl, Michal Dohnal, Pavel Valtr, Martin Grabner, and Vojtěch Bareš
Atmos. Meas. Tech., 13, 6559–6578,Short summary
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,Short summary
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,
F. Joseph Turk, Svetla Hristova-Veleva, Stephen L. Durden, Simone Tanelli, Ousmane Sy, G. David Emmitt, Steve Greco, and Sara Q. Zhang
Atmos. Meas. Tech., 13, 4521–4537,Short summary
The mechanisms linking convection and air motion are major factors in much of the uncertainty in weather prediction, but complementary measurements of these quantities are rarely taken in close proximity. These quantities are shown from the 2017 Convective Processes Experiment (CPEX), wherein cloud and vertical air motion winds derived from the APR-2 airborne Doppler radar are combined with joint Doppler wind lidar (DAWN) measurements in the aerosol-rich regions surrounding the convection.
Chuanliang Zhang, Xuejin Sun, Wen Lu, Yingni Shi, Naiying Dou, and Shaohui Li
Atmos. Meas. Tech. Discuss.,
Preprint under review for AMTShort summary
First spaceborne Doppler wind lidar (DWL) Aeolus operates on sun-synchronous dawn-dusk orbit to lower impact of solar background radiation (SBR) on wind observation accuracy. Increased SBR leads to increment of averaged wind observation uncertainties from 0.3 to 1.4 m/s compared between Aeolus and two added spaceborne DWLs operating on orbits with local ascending time of 15:00 and 12:00. Furthermore, quantitative design of laser pulse energy according to accuracy requirements is also proposed.
Alex T. Chartier, Juha Vierinen, and Geonhwa Jee
Atmos. Meas. Tech., 13, 3023–3031,Short summary
A novel oblique ionospheric radio sounder has been developed and demonstrated in Antarctica. The transmitter was located at McMurdo and the receiver at the South Pole (1356 km great-circle path). The system cycled through 12 frequencies each minute and recorded signal time of flight, intensity, and Doppler. This allowed for the estimation of peak ionospheric electron density, which validated well against independent data from the nearby Jang Bogo ionosonde and GPS TEC.
Alexander V. Rodin, Dmitry V. Churbanov, Sergei G. Zenevich, Artem Y. Klimchuk, Vladimir M. Semenov, Maxim V. Spiridonov, and Iskander S. Gazizov
Atmos. Meas. Tech., 13, 2299–2308,Short summary
The paper presents a new technique in remote wind measurements that may potentially complement conventional aerological observations and eventually greatly improve our knowledge about our climate system, especially concerning processes related to troposphere–stratosphere coupling. The technique may be implemented at relatively low cost in various applications from meteorological observation posts to remote sensing spacecraft.
Kuijun Wu, Weiwei He, Yutao Feng, Yuanhui Xiong, and Faquan Li
Atmos. Meas. Tech., 13, 1817–1824,Short summary
The 1.27 μm O2 dayglow is well-suited for remote sensing in near-space. The main goal of this paper is to discuss the effect of OH radiance on the wind and temperature measurements derived from limb-viewing observations of the O2 dayglow. It is apparent from the simulations that the presence of OH radiance as an interfering species decreases the wind and temperature accuracy at all altitudes, but this effect can be reduced considerably by improving OH radiance knowledge.
Sergey M. Khaykin, Alain Hauchecorne, Robin Wing, Philippe Keckhut, Sophie Godin-Beekmann, Jacques Porteneuve, Jean-Francois Mariscal, and Jerome Schmitt
Atmos. Meas. Tech., 13, 1501–1516,Short summary
The article presents a powerful atmospheric instrument based on a laser radar (lidar), capable of measuring horizontal wind velocity at a wide range of altitudes. In this study, we evaluate the performance of the wind lidar at Observatoire de Haute-Provence and demonstrate the application of its measurements for studies of atmospheric dynamical processes. Finally, we present an example of early validation of the ESA Aeolus space-borne wind lidar using its ground-based predecessor.
Joshua S. Soderholm, Matthew R. Kumjian, Nicholas McCarthy, Paula Maldonado, and Minzheng Wang
Atmos. Meas. Tech., 13, 747–754,Short summary
Collecting measurements of hail size and shape is difficult due to the infrequent and dangerous nature of hailstorms. To improve upon this, a new technique called
HailPixelis introduced for measuring hail using aerial imagery collected by a drone. A combination of machine learning and computer vision methods is used to extract the shape of thousands of hailstones from the aerial imagery. The improved statistics from the much larger HailPixel dataset show significant benefits.
Nikola Vasiljević, Michael Harris, Anders Tegtmeier Pedersen, Gunhild Rolighed Thorsen, Mark Pitter, Jane Harris, Kieran Bajpai, and Michael Courtney
Atmos. Meas. Tech., 13, 521–536,Short summary
In this paper we present the preliminary results of the proof-of-concept (POC) stage of a drone-based wind lidar system development process. To test the POC drone–lidar system we hovered the drone next to mast-mounted sonic anemometers at the Risø test center. The preliminary results of the intercomparison between the measurements derived from the POC system and those of the sonic anemometers show good agreement.
Sylvain Coquillat, Eric Defer, Pierre de Guibert, Dominique Lambert, Jean-Pierre Pinty, Véronique Pont, Serge Prieur, Ronald J. Thomas, Paul R. Krehbiel, and William Rison
Atmos. Meas. Tech., 12, 5765–5790,Short summary
Characteristics of SAETTA lightning imager installed in Corsica are presented, with original observations of lightning activity at regional and lightning scales. SAETTA monitors thunderstorms in a maritime and mountainous region, complex for weather forecasting and sensitive to global warming. A 3-year lightning climatology highlights frequent activity over a specific region due to relief. Uncommonly high discharge in stratiform thundercloud may support a recent model of charging processes.
Ahoro Adachi and Hiroyuki Hashiguchi
Atmos. Meas. Tech., 12, 5699–5715,Short summary
The radio acoustic sounding system is a remote sensing technique that provides vertical profiles of temperature in the air. Since RASS is accompanied with loud noise around the site, acoustic sources having low side lobe levels are desired. Thus, the application of parametric acoustic array as a high-directivity acoustic source was exploited in this study. The results show that the PAA–RASS has accuracy and precision comparable with conventional RASS despite its high directivity of sound.
Atsushi Okazaki, Takumi Honda, Shunji Kotsuki, Moeka Yamaji, Takuji Kubota, Riko Oki, Toshio Iguchi, and Takemasa Miyoshi
Atmos. Meas. Tech., 12, 3985–3996,Short summary
The JAXA is surveying the feasibility of a potential satellite mission equipped with a precipitation radar on a geostationary orbit, as a successor of the GPM Core Observatory. We investigate what kind of observation data will be available from the radar using simulation techniques. Although the quality of the observation depends on the radar specifications and the position of precipitation systems, the results demonstrate that it would be possible to obtain three-dimensional precipitation data.
Jorge Luis Chau, Juan Miguel Urco, Juha Pekka Vierinen, Ryan Andrew Volz, Matthias Clahsen, Nico Pfeffer, and Jörg Trautner
Atmos. Meas. Tech., 12, 2113–2127,Short summary
New systems to study the mesosphere are introduced. They result from the reengineering of previous systems, by making use of MIMO, spread-spectrum and compressed-sensing techniques that are widely used in telecommunications. The interferometer configuration is now implemented in transmission, making the location of meteor echoes possible with just one antenna on reception. Our novel concept makes the study of a mesosphere volume from different viewing points on the ground feasible and easy.
Gwo-Jong Huang, Viswanathan N. Bringi, Andrew J. Newman, Gyuwon Lee, Dmitri Moisseev, and Branislav M. Notaroš
Atmos. Meas. Tech., 12, 1409–1427,Short summary
This paper proposes a method for snow rate (SR) estimation using observations collected by NASA dual-frequency dual-polarized (D3R) radar during the GPM Cold-season Precipitation Experiment (GCPEx). The new method utilizes dual-wavelength radar reflectivity ratio (DWR) and 2-D-video disdrometer (2DVD) measurements to improve SR estimation accuracy. It is validated by comparing the D3R radar-retrieved SR with accumulated SR directly measured by a Pluvio gauge for an entire GCPEx synoptic event.
Giovanni Bianchini, Francesco Castagnoli, Gianluca Di Natale, and Luca Palchetti
Atmos. Meas. Tech., 12, 619–635,Short summary
The characterization of infrared radiation emitted by the atmosphere is a crucial task in the study of the Earth's climate. The Radiation Explorer in the Far Infrared (REFIR) spectroradiometer allows us to perform this task adding the capability of resolving, through spectroscopy, the atmospheric components responsible for the measured radiative effects. The analysis of the measurements also allows us to retrieve the atmospheric structure, making REFIR a complete tool for atmospheric studies.
Tetsu Sakai, Tomohiro Nagai, Toshiharu Izumi, Satoru Yoshida, and Yoshinori Shoji
Atmos. Meas. Tech., 12, 313–326,Short summary
We developed an automated compact mobile Raman lidar (MRL) system for measuring the vertical distribution of the water vapor mixing ratio in the lower troposphere, which has an affordable cost and is easy to operate. The MRL was installed in a small trailer for easy deployment and can start measurement in a few hours, and it is capable of unattended operation for several months. We describe the MRL system and present validation results obtained by comparing with the other humidity sensors.
Mengistu Wolde, Alessandro Battaglia, Cuong Nguyen, Andrew L. Pazmany, and Anthony Illingworth
Atmos. Meas. Tech., 12, 253–269,Short summary
This paper presents an implementation of polarization diversity pulse-pair processing (PDPP) on the National Research Council of Canada airborne W-band radar (NAW) system. A description of the NAW PDPP pulsing schemes and an analysis of comprehensive airborne data collected in diverse weather conditions in Canada is presented. The analysis shows a successful airborne measurement of Doppler velocity exceeding 100 m s−1 using PDPP approach, the first such measurement from a moving platform.
Nuno Pereira, David Bolsée, Peter Sperfeld, Sven Pape, Dominique Sluse, and Gaël Cessateur
Atmos. Meas. Tech., 11, 6605–6615,Short summary
The knowledge of the solar spectrum at the top of Earth's atmosphere is of great importance for climatic studies. Satellite instruments allow direct measurements; however, their calibration presents issues. It is possible to determine this spectrum precisely from Earth-based measurements as well, using the Langley plot technique and accurate calibration techniques. We present an infrared spectrum using these techniques for measurements made at the reference Mauna Loa Observatory.
Alessandro Battaglia, Ranvir Dhillon, and Anthony Illingworth
Atmos. Meas. Tech., 11, 5965–5979,Short summary
A new technique is proposed to simulated winds in clouds as they could be observed by a space-borne Doppler 3 mm wavelength radar. Results show that, in the presence of cloud inhomogeneity and of vertical wind shear, measured winds can be corrected and produce unbiased estimates of line-of-sight winds that can then be assimilated in numerical models to improve weather forecasts.
Yueqiang Sun, Weihua Bai, Congliang Liu, Yan Liu, Qifei Du, Xianyi Wang, Guanglin Yang, Mi Liao, Zhongdong Yang, Xiaoxin Zhang, Xiangguang Meng, Danyang Zhao, Junming Xia, Yuerong Cai, and Gottfried Kirchengast
Atmos. Meas. Tech., 11, 5797–5811,Short summary
The GNSS Occultation Sounder (GNOS) is one of the new-generation payloads on board the Chinese FengYun 3 (FY-3) series of operational meteorological satellites for sounding the Earth’s neutral atmosphere and ionosphere. FY-3C GNOS, on board the FY-3 series C satellite launched in September 2013, was designed to acquire setting and rising radio occultation (RO) data by using GNSS signals from both the Chinese BDS and the US GPS. This paper reviews the FY-3C GNOS mission.
Jonas Hagen, Axel Murk, Rolf Rüfenacht, Sergey Khaykin, Alain Hauchecorne, and Niklaus Kämpfer
Atmos. Meas. Tech., 11, 5007–5024,
Friedhelm Olschewski, Christian Monte, Albert Adibekyan, Max Reiniger, Berndt Gutschwager, Joerg Hollandt, and Ralf Koppmann
Atmos. Meas. Tech., 11, 4757–4762,Short summary
The Institute for Atmospheric and Environmental Research at the University of Wuppertal designed and manufactured a prototype of the large-area blackbody for in-flight calibration of an infrared interferometer deployed onboard a long-duration balloon for stratospheric research.
Thomas C. van Leth, Aart Overeem, Hidde Leijnse, and Remko Uijlenhoet
Atmos. Meas. Tech., 11, 4645–4669,Short summary
We present a campaign to address several error sources associated with rainfall estimates from microwave links in cellular communication networks. The set-up consists of three co-located links, complemented with reference instruments. We investigate events covering different attenuating phenomena: Rainfall, solid precipitation, temperature, fog, antenna wetting due to rain or dew, and clutter.
Philippe Baron, Donal Murtagh, Patrick Eriksson, Jana Mendrok, Satoshi Ochiai, Kristell Pérot, Hideo Sagawa, and Makoto Suzuki
Atmos. Meas. Tech., 11, 4545–4566,Short summary
This paper investigates with computer simulations the measurement performances of the satellite Stratospheric Inferred Winds (SIW) in the altitude range 10–90 km. SIW is a Swedish mission that will be launched close to 2022. It is intended to fill the current altitude gap between 30 and 70 km in wind measurements and to pursue the monitoring of temperature and key stratospheric constituents for better understanding climate change effects.
Jay Herman, Guoyong Wen, Alexander Marshak, Karin Blank, Liang Huang, Alexander Cede, Nader Abuhassan, and Matthew Kowalewski
Atmos. Meas. Tech., 11, 4373–4388,Short summary
The DSCOVR/EPIC instrument located near the Lagrange 1 Earth–Sun gravitational balance point is able to view the entire sunlit disk of the Earth. This means that during the eclipse of 21 August 2017 EPIC was able to see the region of totality and the much larger region of partial eclipse. Because of this, EPIC is able to measure the global reduction of reflected solar flux. For the wavelength range 388 to 780 nm, we estimated a 10 % reduction in reflected radiation.
Martin Kaufmann, Friedhelm Olschewski, Klaus Mantel, Brian Solheim, Gordon Shepherd, Michael Deiml, Jilin Liu, Rui Song, Qiuyu Chen, Oliver Wroblowski, Daikang Wei, Yajun Zhu, Friedrich Wagner, Florian Loosen, Denis Froehlich, Tom Neubert, Heinz Rongen, Peter Knieling, Panos Toumpas, Jinjun Shan, Geshi Tang, Ralf Koppmann, and Martin Riese
Atmos. Meas. Tech., 11, 3861–3870,Short summary
The concept and optical layout of a limb sounder using a spatial heterodyne spectrometer is presented. The instrument fits onto a nano-satellite platform, such as a CubeSat. It is designed for the derivation of temperatures in the mesosphere and lower thermosphere. The design parameters of the optics and a radiometric assessment of the instrument as well as the main characterization and calibration steps are discussed.
Norman Wildmann, Nikola Vasiljevic, and Thomas Gerz
Atmos. Meas. Tech., 11, 3801–3814,Short summary
Wind turbines extract energy from the flow which manifests in a region of lower wind speeds and increased turbulence downstream of the rotor, the so-called wake. Understanding the characteristics of the wake is a key challenge for wind-energy research. A new strategy for measuring the wind in the wake with three synchronized lidar instruments is presented. The measurement points are automatically adapted to the prevailing wind direction to achieve continuous monitoring of wake properties.
Oliver Lux, Christian Lemmerz, Fabian Weiler, Uwe Marksteiner, Benjamin Witschas, Stephan Rahm, Andreas Schäfler, and Oliver Reitebuch
Atmos. Meas. Tech., 11, 3297–3322,Short summary
This work reports airborne wind lidar observations performed in a recent field campaign. The deployed lidar system serves as a demonstrator for the satellite instrument ALADIN on board Aeolus, which is scheduled for launch in 2018 and will become the first wind lidar in space. After presenting the measurement principle, operation procedures and wind retrieval algorithm, the obtained wind results are validated and discussed, providing valuable information in preparation for the satellite mission.
Xiaochun Zhai, Songhua Wu, Bingyi Liu, Xiaoquan Song, and Jiaping Yin
Atmos. Meas. Tech., 11, 1313–1331,Short summary
A Doppler wind lidar attitude correction method is presented. This algorithm-based method relaxes the requirements for mechanical stability and active compensation mechanisms. A shipborne wind measurement campaign was carried out in the Yellow Sea, 2014. Comparison between lidar and radiosonde wind measurements shows good consistency, indicating that the method can provide continuous and high spatio-temporal resolution measurement of atmospheric turbulence processes in the marine boundary layer.
Patricia Liebing, Matthijs Krijger, Ralph Snel, Klaus Bramstedt, Stefan Noël, Heinrich Bovensmann, and John P. Burrows
Atmos. Meas. Tech., 11, 265–289,Short summary
This article describes a method to determine the polarization sensitivity of SCIAMACHY, a spectrometer on Envisat, from in-orbit data. Polarization is a preference of a direction in which light oscillates, and many optical instruments suffer from a dependence of their measured signals on this. To measure and correct for this effect, a statistical analysis of in-flight data combined with a model of the atmosphere and the instrument was performed, showing that the instrument changed after launch.
Imke Hans, Martin Burgdorf, Viju O. John, Jonathan Mittaz, and Stefan A. Buehler
Atmos. Meas. Tech., 10, 4927–4945,Short summary
In our article we present the evolution of the noise of 11 microwave radiometers used for meteorological remote sensing. We used the Allan deviation to compute an estimate of the noise on the calibration measurements. We provide graphics as an overview to enable the users of the data to decide on the usability of the data for their purposes. Moreover, our analysis enters the production of new FCDRs (Fundamental Climate Data Records) within the FIDUCEO project.
Ilias Fountoulakis, Alberto Redondas, Kaisa Lakkala, Alberto Berjon, Alkiviadis F. Bais, Lionel Doppler, Uwe Feister, Anu Heikkila, Tomi Karppinen, Juha M. Karhu, Tapani Koskela, Katerina Garane, Konstantinos Fragkos, and Volodya Savastiouk
Atmos. Meas. Tech., 10, 4491–4505,Short summary
Results of the temperature characterization of the global UV spectral measurements of eight different Brewer spectrophotometers operating in Greece, Finland, Germany and Spain are presented. Different temperature characterization methods are evaluated and an improved methodology for the correction of the measurements for the effects of temperature is presented.
Leonie Bernet, Francisco Navas-Guzmán, and Niklaus Kämpfer
Atmos. Meas. Tech., 10, 4421–4437,Short summary
Microwave radiometry is a suitable technique to measure atmospheric temperature profiles during clear sky and cloudy conditions. However clouds can influence the temperature measurements. In this study we analyse the influence of clouds on temperature measurements in the troposphere from a microwave radiometer. We found that the effect of clouds on the temperature measurements is important and that the measurements can be improved substantially by considering clouds in the retrieval process.
Nikola Vasiljević, José M. L. M. Palma, Nikolas Angelou, José Carlos Matos, Robert Menke, Guillaume Lea, Jakob Mann, Michael Courtney, Luis Frölen Ribeiro, and Vitor M. M. G. C. Gomes
Atmos. Meas. Tech., 10, 3463–3483,Short summary
In this paper we present a methodology for atmospheric multi-Doppler lidar experiments accompanied with the description and results from the Perdigão-2015 experiment, where the methodology was demonstrated. To our knowledge, this is the first time that steps leading to the acquisition of high-quality datasets from field studies are described and systematically defined and organized.
Leslie David, Olivier Bock, Christian Thom, Pierre Bosser, and Jacques Pelon
Atmos. Meas. Tech., 10, 2745–2758,Short summary
The Raman lidar ability to retrieve atmospheric water vapor with high accuracy makes it a premium instrument in different research fields such as climatology, meteorology, or calibration of GNSS altimetry data. In order to achieve long-term stability of the measurements, the system has to be carefully calibrated. In this work we strove to investigate and mitigate the error and instability sources through numerical simulations as well as experimental tests.
Klaus Bramstedt, Thomas C. Stone, Manfred Gottwald, Stefan Noël, Heinrich Bovensmann, and John P. Burrows
Atmos. Meas. Tech., 10, 2413–2423,Short summary
The satellite instrument SCIAMACHY on board the ESA's platform Envisat (2002–2012) performed observations of the Earth's atmosphere. Using sun and moon observations of the instrument itself, we derived a set of correction parameters for the determination of the viewing directions of the instrument. From this work, all vertical profiles of atmospheric parameters from SCIAMACHY's limb and occultation measurements will be improved by a more accurate altitude information.
Rui Valente de Almeida and Pedro Vieira
Atmos. Meas. Tech., 10, 2299–2311,Short summary
This paper presents the Forest Fire Finder (FFF) System, a long range forest fire detection system. It works by detecting a smoke column above the horizon, by analysing the light that goes through it. In the article, you will find a technical description and an analysis of the behaviour of 13 of these devices, which were installed in a Portuguese national park. We conclude that the deployed FFF network managed to detect more that 200 fires, proving the system to be effective in fire detection.
V. M. Erik Schenkeveld, Glen Jaross, Sergey Marchenko, David Haffner, Quintus L. Kleipool, Nico C. Rozemeijer, J. Pepijn Veefkind, and Pieternel F. Levelt
Atmos. Meas. Tech., 10, 1957–1986,Short summary
The Ozone Monitoring Instrument (OMI) has been flying on NASA’s EOS Aura satellite since July 15, 2004. It has measured the concentration of trace gasses in the atmosphere, like ozone, NO2 and SO2. This article describes the trend in performance and calibration parameters of OMI during 12 years of flight. The degradation of the CCD detectors, solar diffusers, spectral calibration and row anomaly are shown. The instrument shows overall degradation that is better than expected.
Katherine McCaffrey, Laura Bianco, Paul Johnston, and James M. Wilczak
Atmos. Meas. Tech., 10, 999–1015,Short summary
Using an optimized turbulence mode of two wind profiling radars (449 MHz and 915 MHz) during the XPIA field campaign, we present improved measurements of vertical velocity variance at the resolved and unresolved scales, using first and second Doppler spectral moments, and the total variance over all scales. Comparisons with sonic anemometers gave strong results, particularly during the daytime convective period. Profiles up to 2 km are possible with the 449 MHz WPR and 1 km from the 915 MHz WPR.
Grant W. Petty and Ralf Bennartz
Atmos. Meas. Tech., 10, 745–758,Short summary
The Global Precipitation Measurement (GPM) Microwave Imager (GMI) is a new satellite instrument for observing global rainfall and snowfall. This paper documents the effective spatial resolution of the GMI's microwave imagery and describes the results of a computational method for optimally matching the resolutions of different channels.
René Sedlak, Patrick Hannawald, Carsten Schmidt, Sabine Wüst, and Michael Bittner
Atmos. Meas. Tech., 9, 5955–5963,Short summary
In this paper a SWIR airglow imager is presented. It is especially designed for the observation of small-scale gravity waves and turbulence features in the OH airglow layer with a high spatio-temporal resolution of up to 17 m (at mesopause heights) and 2.5 to 2.8 s. Two case studies show small-scale wave structures with horizontal wavelengths of approximately 550 m as well as vortex formation and decomposition of wave fronts, both indicating the onset of turbulence.
Mattia Vaccarono, Renzo Bechini, Chandra V. Chandrasekar, Roberto Cremonini, and Claudio Cassardo
Atmos. Meas. Tech., 9, 5367–5383,Short summary
The data quality of radars must be ensured and continuously monitored. The aim of this paper is to provide an integrated approach able to monitor the calibration of operational dual-polarization radars. The set of methods considered appears suitable to establish an online tool to monitor the stability of the radar calibration with an accuracy of about 2 dB. This is considered adequate to automatically detect any unexpected change in the radar system requiring further investigations.
Franz-Josef Lübken, Gerd Baumgarten, Jens Hildebrand, and Francis J. Schmidlin
Atmos. Meas. Tech., 9, 3911–3919,Short summary
Wind measurements in the middle atmosphere (MA) are crucial to our understanding of atmospheric processes. We have recently developed a new laser-based method to measure winds called DoRIS (Doppler Rayleigh Iodine Spectrometer) which is the only technique to monitor winds in the middle atmosphere quasi-continuously. We compare our measurements with rocket-borne measurements and find excellent agreement above 30 km. DoRIS can now be considered as a validated method to measure winds in the MA.
Michael Gerding, Maren Kopp, Josef Höffner, Kathrin Baumgarten, and Franz-Josef Lübken
Atmos. Meas. Tech., 9, 3707–3715,Short summary
Temperature soundings by lidar are an important tool for the understanding of the middle atmosphere, including gravity waves and tides. Though, mesospheric lidar soundings at daytime are rare. We describe a daylight-capable RMR lidar with optical bandwidths in the range of the Doppler broadened laser backscatter. We account for the systematic temperature error induced by the optical filter, and present examples of daylight-independent temperature sounding as well as tidal analysis.
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Ground-based observations of GPS satellites disappearing below the local horizon are analysed. Starting at +2 degree elevation angle the GPS signals are recorded in open-loop tracking mode down to −1.5 degrees. The open-loop Doppler model has negligible influence on the derived data products for strong signal-to-noise ratios; at lower signal levels, however, a notable bias is uncovered. These results may have implications for the design of future space-based GPS radio occultation missions.
Ground-based observations of GPS satellites disappearing below the local horizon are analysed....