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Atmospheric Measurement Techniques
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AMT | Articles | Volume 13, issue 2
Atmos. Meas. Tech., 13, 537–551, 2020
https://doi.org/10.5194/amt-13-537-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-13-537-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
Atmos. Meas. Tech., 13, 537–551, 2020
https://doi.org/10.5194/amt-13-537-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/amt-13-537-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
Research article 07 Feb 2020
Research article | 07 Feb 2020
Improved fuzzy logic method to distinguish between meteorological and non-meteorological echoes using C-band polarimetric radar data
Shuai Zhang et al.
Related subject area
Subject: Others (Wind, Precipitation, Temperature, etc.) | Technique: Remote Sensing | Topic: Data Processing and Information Retrieval
Rain event detection in commercial microwave link attenuation data using convolutional neural networks
Preliminary investigation of the relationship between differential phase shift and path-integrated attenuation at the X band frequency in an Alpine environment
Observation of sensible and latent heat flux profiles with lidar
Methodology for deriving the telescope focus function and its uncertainty for a heterodyne pulsed Doppler lidar
Update of Infrared Atmospheric Sounding Interferometer (IASI) channel selection with correlated observation errors for numerical weather prediction (NWP)
Learning about the vertical structure of radar reflectivity using hydrometeor classes and neural networks in the Swiss Alps
Toward a variational assimilation of polarimetric radar observations in a convective-scale numerical weather prediction (NWP) model
Estimating raindrop size distributions using microwave link measurements: potential and limitations
An LES-based airborne Doppler lidar simulator and its application to wind profiling in inhomogeneous flow conditions
Analysis of flow in complex terrain using multi-Doppler lidar retrievals
Unsupervised classification of vertical profiles of dual polarization radar variables
Monitoring the differential reflectivity and receiver calibration of the German polarimetric weather radar network
A channel selection method for hyperspectral atmospheric infrared sounders based on layering
Advanced hodograph-based analysis technique to derive gravity-wave parameters from lidar observations
Rayleigh wind retrieval for the ALADIN airborne demonstrator of the Aeolus mission using simulated response calibration
Determining the daytime Earth radiative flux from National Institute of Standards and Technology Advanced Radiometer (NISTAR) measurements
Determination of time-varying periodicities in unequally spaced time series of OH* temperatures using a moving Lomb–Scargle periodogram and a fast calculation of the false alarm probabilities
Towards improved turbulence estimation with Doppler wind lidar VAD scans
A GPS water vapour tomography method based on a genetic algorithm
kCARTA: a fast pseudo line-by-line radiative transfer algorithm with analytic Jacobians, fluxes, nonlocal thermodynamic equilibrium, and scattering for the infrared
Improved SIFTER v2 algorithm for long-term GOME-2A satellite retrievals of fluorescence with a correction for instrument degradation
Potential for the measurement of mesosphere and lower thermosphere (MLT) wind, temperature, density and geomagnetic field with Superconducting Submillimeter-Wave Limb-Emission Sounder 2 (SMILES-2)
Optimised degradation correction for SCIAMACHY satellite solar measurements from 330 to 1600 nm by using its internal white light source
Estimation of turbulence dissipation rate from Doppler wind lidars and in situ instrumentation for the Perdigão 2017 campaign
An experimental 2D-Var retrieval using AMSR2
Retrieval of intrinsic mesospheric gravity wave parameters using lidar and airglow temperature and meteor radar wind data
Determination of ice water content (IWC) in tropical convective clouds from X-band dual-polarization airborne radar
Retrieval of temperature from a multiple channel pure rotational Raman backscatter lidar using an optimal estimation method
Combined use of volume radar observations and high-resolution numerical weather predictions to estimate precipitation at the ground: methodology and proof of concept
A Gaussian mixture method for specific differential phase retrieval at X-band frequency
Analysis of the lightning production of convective cells
Multiple technical observations of the atmospheric boundary layer structure of a red-alert haze episode in Beijing
Characterization of shallow oceanic precipitation using profiling and scanning radar observations at the Eastern North Atlantic ARM observatory
Assimilation of GNSS tomography products into the Weather Research and Forecasting model using radio occultation data assimilation operator
Tropopause altitude determination from temperature profile measurements of reduced vertical resolution
A generalized simulation capability for rotating- beam scatterometers
Automated wind turbine wake characterization in complex terrain
Polarimetric radar characteristics of lightning initiation and propagating channels
Processing and quality control of FY-3C GNOS data used in numerical weather prediction applications
Neural network radiative transfer for imaging spectroscopy
Investigation of observational error sources in multi-Doppler-radar three-dimensional variational vertical air motion retrievals
Better turbulence spectra from velocity–azimuth display scanning wind lidar
The use of GNSS zenith total delays in operational AROME/Hungary 3D-Var over a central European domain
Application of the Fengyun 3 C GNSS occultation sounder for assessing the global ionospheric response to a magnetic storm event
Development of time-varying global gridded Ts–Tm model for precise GPS–PWV retrieval
Enhancing the spatiotemporal features of polar mesosphere summer echoes using coherent MIMO and radar imaging at MAARSY
3-D tomographic limb sounder retrieval techniques: irregular grids and Laplacian regularisation
A novel post-processing algorithm for Halo Doppler lidars
A new MesosphEO data set of temperature profiles from 35 to 85 km using Rayleigh scattering at limb from GOMOS/ENVISAT daytime observations
High-resolution temperature profiles retrieved from bichromatic stellar scintillation measurements by GOMOS/Envisat
Julius Polz, Christian Chwala, Maximilian Graf, and Harald Kunstmann
Atmos. Meas. Tech., 13, 3835–3853, https://doi.org/10.5194/amt-13-3835-2020, https://doi.org/10.5194/amt-13-3835-2020, 2020
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Commercial microwave link (CML) networks can be used to estimate path-averaged rain rates. This study evaluates the ability of convolutional neural networks to distinguish between wet and dry periods in CML time series data and the ability to transfer this detection skill to sensors not used for training. Our data set consists of several months of data from 3904 CMLs covering all of Germany. Compared to a previously used detection method, we could show a significant increase in performance.
Guy Delrieu, Anil Kumar Khanal, Nan Yu, Frédéric Cazenave, Brice Boudevillain, and Nicolas Gaussiat
Atmos. Meas. Tech., 13, 3731–3749, https://doi.org/10.5194/amt-13-3731-2020, https://doi.org/10.5194/amt-13-3731-2020, 2020
Andreas Behrendt, Volker Wulfmeyer, Christoph Senff, Shravan Kumar Muppa, Florian Späth, Diego Lange, Norbert Kalthoff, and Andreas Wieser
Atmos. Meas. Tech., 13, 3221–3233, https://doi.org/10.5194/amt-13-3221-2020, https://doi.org/10.5194/amt-13-3221-2020, 2020
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In order to understand how solar radiation energy hitting the ground is distributed into the atmosphere, we use a new combination of laser-based remote-sensing techniques to quantify these energy fluxes up to heights of more than 1 km above ground. Before, similar techniques had already been presented for determining the energy flux component regarding the exchange of humidity but not the warm air itself. Now, we show that this can also be measured by remote sensing with low uncertainties.
Pyry Pentikäinen, Ewan James O'Connor, Antti Juhani Manninen, and Pablo Ortiz-Amezcua
Atmos. Meas. Tech., 13, 2849–2863, https://doi.org/10.5194/amt-13-2849-2020, https://doi.org/10.5194/amt-13-2849-2020, 2020
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We provide a methodology for obtaining a function describing how the Doppler lidar telescope configuration
impacts the measurements. Together with the function itself, we also provide the uncertainties in the function, which propagate through to provide uncertainties in the geophysical quantities obtained from the measurements. The method can be used to determine how stable the instrument is over time and also identify if changes have been made in the instrument setup.
Olivier Coopmann, Vincent Guidard, Nadia Fourrié, Béatrice Josse, and Virginie Marécal
Atmos. Meas. Tech., 13, 2659–2680, https://doi.org/10.5194/amt-13-2659-2020, https://doi.org/10.5194/amt-13-2659-2020, 2020
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The objective of this paper is to make a new selection of IASI channels by taking into account inter-channel observation-error correlations. Our selection further reduces the analysis error by 3 % in temperature, 1.8 % in humidity and 0.9 % in ozone compared to Collard’s selection, when using the same number of channels. A selection of 400 IASI channels is proposed at the end of the paper which is able to further reduce analysis errors.
Floor van den Heuvel, Loris Foresti, Marco Gabella, Urs Germann, and Alexis Berne
Atmos. Meas. Tech., 13, 2481–2500, https://doi.org/10.5194/amt-13-2481-2020, https://doi.org/10.5194/amt-13-2481-2020, 2020
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In areas with reduced visibility at the ground level, radar precipitation measurements higher up in the atmosphere need to be extrapolated to the ground and be corrected for the vertical change (i.e. growth and transformation) of precipitation. This study proposes a method based on hydrometeor proportions and machine learning (ML) to apply these corrections at smaller spatiotemporal scales. In comparison with existing techniques, the ML methods can make predictions from higher altitudes.
Guillaume Thomas, Jean-François Mahfouf, and Thibaut Montmerle
Atmos. Meas. Tech., 13, 2279–2298, https://doi.org/10.5194/amt-13-2279-2020, https://doi.org/10.5194/amt-13-2279-2020, 2020
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This paper presents the potential of a polarimetric weather radar observation operator for hydrometeor content initialization. The non-linear operator allows to simulate ZHH, ZDR, KDP and ρHV, using the T-Matrix method, prognostic variables forecasted by the AROME-France NWP model and a one-moment microphysical scheme. After sensitivity studies, it has been found that ZHH and ZDR are good candidates for hydrometeor initialization and that KDP seems useful for rain content only.
Thomas C. van Leth, Hidde Leijnse, Aart Overeem, and Remko Uijlenhoet
Atmos. Meas. Tech., 13, 1797–1815, https://doi.org/10.5194/amt-13-1797-2020, https://doi.org/10.5194/amt-13-1797-2020, 2020
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We present a method of using collocated microwave link instruments to estimate the average size distribution of raindrops along a path of several kilometers. Our method is validated using simulated fields as well as five laser disdrometers installed along a path. We also present preliminary results from an experimental setup measuring at 26 and 38 GHz along a 2.2 km path. We show that a retrieval on the basis of microwave links can be highly accurate, provided the base power level is stable.
Philipp Gasch, Andreas Wieser, Julie K. Lundquist, and Norbert Kalthoff
Atmos. Meas. Tech., 13, 1609–1631, https://doi.org/10.5194/amt-13-1609-2020, https://doi.org/10.5194/amt-13-1609-2020, 2020
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We present an airborne Doppler lidar simulator (ADLS) based on high-resolution atmospheric wind fields (LES). The ADLS is used to evaluate the retrieval accuracy of airborne wind profiling under turbulent, inhomogeneous wind field conditions inside the boundary layer. With the ADLS, the error due to the violation of the wind field homogeneity assumption used for retrieval can be revealed. For the conditions considered, flow inhomogeneities exert a dominant influence on wind profiling error.
Tyler M. Bell, Petra Klein, Norman Wildmann, and Robert Menke
Atmos. Meas. Tech., 13, 1357–1371, https://doi.org/10.5194/amt-13-1357-2020, https://doi.org/10.5194/amt-13-1357-2020, 2020
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This study investigates the utility of using multi-Doppler retrievals during the Perdigão 2017 campaign. By combining scans from the multitude of Doppler lidars, it was possible to derive virtual towers that greatly extend the range of traditional in situ meteorological towers. Uncertainties from the measurements are analyzed and discussed. Despite multiple sources of error, it was found that the virtual towers are useful for analyzing the complex flows observed during the campaign.
Jussi Tiira and Dmitri Moisseev
Atmos. Meas. Tech., 13, 1227–1241, https://doi.org/10.5194/amt-13-1227-2020, https://doi.org/10.5194/amt-13-1227-2020, 2020
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Modern weather radars are sensitive for properties of precipitating snow particles, such as their sizes, shapes and number concentration. Vertical profiles of such radar measurements can be used for studying the processes through which snow is formed. We created a profile classification method for this purpose, and we show how it can be used for automatic identification of snow growth processes. Being able to identify the processes is expected to improve radar-based precipitation estimation.
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.
Shujie Chang, Zheng Sheng, Huadong Du, Wei Ge, and Wei Zhang
Atmos. Meas. Tech., 13, 629–644, https://doi.org/10.5194/amt-13-629-2020, https://doi.org/10.5194/amt-13-629-2020, 2020
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Because a satellite channel’s ability to resolve hyperspectral data varies with height, an improved channel selection method is proposed based on information content. An improved channel selection scheme (ICS) for a hyperspectral atmospheric infrared sounder using AIRS data based on layering is proposed. The accuracy of the retrieval temperature is improved by using our method, which means the ICS method selected in this paper is feasible and shows great promise for various applications.
Irina Strelnikova, Gerd Baumgarten, and Franz-Josef Lübken
Atmos. Meas. Tech., 13, 479–499, https://doi.org/10.5194/amt-13-479-2020, https://doi.org/10.5194/amt-13-479-2020, 2020
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One of the major problems of climate and weather modeling is atmospheric gravity waves. All measured meteorological parameters such as winds and temperature reveal superposition of large-scale background field and small-scale features created by waves. We developed an analysis technique that decomposes the measured winds and temperature into single waves, which allows for a detailed description of wave parameters. Application of this technique will improve understanding of atmospheric dynamics.
Xiaochun Zhai, Uwe Marksteiner, Fabian Weiler, Christian Lemmerz, Oliver Lux, Benjamin Witschas, and Oliver Reitebuch
Atmos. Meas. Tech., 13, 445–465, https://doi.org/10.5194/amt-13-445-2020, https://doi.org/10.5194/amt-13-445-2020, 2020
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An airborne prototype called A2D was developed for validating the Aeolus measurement principle based on realistic atmospheric signals. However, the atmospheric and instrumental variability currently limit the reliability and repeatability of the measured Rayleigh response calibration (MRRC), which is a prerequisite for accurate wind retrieval. A procedure for a simulated Rayleigh response calibration (SRRC) is developed and presented to resolve these limitations of the A2D Rayleigh channel MRRC.
Wenying Su, Patrick Minnis, Lusheng Liang, David P. Duda, Konstantin Khlopenkov, Mandana M. Thieman, Yinan Yu, Allan Smith, Steven Lorentz, Daniel Feldman, and Francisco P. J. Valero
Atmos. Meas. Tech., 13, 429–443, https://doi.org/10.5194/amt-13-429-2020, https://doi.org/10.5194/amt-13-429-2020, 2020
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The Deep Space Climate Observatory (DSCOVR) provides continuous full-disk global broadband irradiance measurements over most of the sunlit side of the Earth. The three active cavity radiometers measure the total radiant energy from the sunlit side of the Earth in shortwave (SW; 0.2–4 µm), total (0.4–100 µm), and near-infrared (NIR; 0.7–4 µm) channels. In this paper, the algorithm used to derive daytime shortwave and longwave fluxes from NISTAR measurements is presented.
Christoph Kalicinsky, Robert Reisch, Peter Knieling, and Ralf Koppmann
Atmos. Meas. Tech., 13, 467–477, https://doi.org/10.5194/amt-13-467-2020, https://doi.org/10.5194/amt-13-467-2020, 2020
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This study presents an approach to analyse unequally spaced time series of OH* temperatures with respect to time-varying periodic fluctuations. The approach is based on the classical Lomb–Scargle periodogram and, additionally, the idea of a moving window is used. Furthermore, a fast and easy way to analyse the significance of the results is presented. The general performance of the approach is tested with artificially generated time series and results for real observations are presented.
Norman Wildmann, Eileen Päschke, Anke Roiger, and Christian Mallaun
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2020-8, https://doi.org/10.5194/amt-2020-8, 2020
Revised manuscript accepted for AMT
Fei Yang, Jiming Guo, Junbo Shi, Xiaolin Meng, Yinzhi Zhao, Lv Zhou, and Di Zhang
Atmos. Meas. Tech., 13, 355–371, https://doi.org/10.5194/amt-13-355-2020, https://doi.org/10.5194/amt-13-355-2020, 2020
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The development of GPS station networks that provide rich data sources containing atmospheric information will enable more GPS applications in the field of meteorology. This study describes a genetic algorithm for the water vapour tomography; overcomes the ill-conditioned problem; and eliminates the reliance on excessive constraints, priori information, and external data. It is proven in the paper that accurate 3-D water vapour distribution can be provided by this study for atmospheric research.
Sergio DeSouza-Machado, L. Larrabee Strow, Howard Motteler, and Scott Hannon
Atmos. Meas. Tech., 13, 323–339, https://doi.org/10.5194/amt-13-323-2020, https://doi.org/10.5194/amt-13-323-2020, 2020
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The current instruments being used for weather forecasting and climate require accurate radiative transfer codes to process the acquired data. In addition the codes are becoming more realistic, as they can now account for the effects of cloud and aerosols, rather than only simulating radiances for a clear sky. We describe a fast, accurate, and general purpose code that we have developed to help model data from these instruments.
Erik van Schaik, Maurits L. Kooreman, Piet Stammes, L. Gijsbert Tilstra, Olaf N. E. Tuinder, Abram F. J. Sanders, Willem W. Verstraeten, Ruediger Lang, Alessandra Cacciari, Joanna Joiner, Wouter Peters, and K. Folkert Boersma
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2019-384, https://doi.org/10.5194/amt-2019-384, 2020
Revised manuscript accepted for AMT
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With our improved algorithm we have generated a stable, long-term dataset of fluorescence measurements from the GOME-2A satellite instrument. In this study we determined a correction for the degradation of GOME-2A in orbit, and applied this correction along with other improvements to our SIFTER v2 retrieval algorithm. The result is a coherent dataset of daily and monthly averaged fluorescence values for the period 2007–2020 to track worldwide changes in photosynthetic activity by vegetation.
Philippe Baron, Satoshi Ochiai, Eric Dupuy, Richard Larsson, Huixin Liu, Naohiro Manago, Donal Murtagh, Shin-ichiro Oyama, Hideo Sagawa, Akinori Saito, Takatoshi Sakazaki, Masato Shiotani, and Makoto Suzuki
Atmos. Meas. Tech., 13, 219–237, https://doi.org/10.5194/amt-13-219-2020, https://doi.org/10.5194/amt-13-219-2020, 2020
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Submillimeter-Wave Limb-Emission Sounder 2 (SMILES-2) is a satellite mission proposed in Japan to probe the middle and upper atmosphere (20–160 km). The key products are wind, temperature and density. If selected, this mission could provide new insights into vertical coupling in the atmosphere and could help improve weather and climate models. We conducted simulation studies to assess the measurement performances in the altitude range 60–110 km, with a special focus on the geomagnetic effects.
Tina Hilbig, Klaus Bramstedt, Mark Weber, John P. Burrows, and Matthijs Krijger
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2019-433, https://doi.org/10.5194/amt-2019-433, 2019
Revised manuscript accepted for AMT
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One of the main limitations for long-term space-based measurements is the optical degradation of the instrument. We present an optimisation of the degradation correction approach (Krijger et al., 2014) for the SCIAMACHY satellite, which in particular improves the solar spectral data. The main achievement of this study was the successful description of the ageing of SCIAMACHY’s internal white light source and its integration in the existing degradation model.
Norman Wildmann, Nicola Bodini, Julie K. Lundquist, Ludovic Bariteau, and Johannes Wagner
Atmos. Meas. Tech., 12, 6401–6423, https://doi.org/10.5194/amt-12-6401-2019, https://doi.org/10.5194/amt-12-6401-2019, 2019
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Turbulence is the variation of wind velocity on short timescales. In this study we introduce a new method to measure turbulence in a two-dimensionial plane with lidar instruments. The method allows for the detection and quantification of subareas of distinct turbulence conditions in the observed plane. We compare the results to point and profile measurements with more established instruments. It is shown that turbulence below low-level jets and in wind turbine wakes can be investigated this way.
David Ian Duncan, Patrick Eriksson, and Simon Pfreundschuh
Atmos. Meas. Tech., 12, 6341–6359, https://doi.org/10.5194/amt-12-6341-2019, https://doi.org/10.5194/amt-12-6341-2019, 2019
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The overlapping beams of some satellite observations contain spatial information that is discarded by most data processing techniques. This study applies an established technique in a new way to improve the spatial resolution of retrieval targets, effectively using the overlapping information to achieve a higher ultimate resolution. It is argued that this is a more optimal use of the total information available from current microwave sensors, using AMSR2 as an example.
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.
Cuong M. Nguyen, Mengistu Wolde, and Alexei Korolev
Atmos. Meas. Tech., 12, 5897–5911, https://doi.org/10.5194/amt-12-5897-2019, https://doi.org/10.5194/amt-12-5897-2019, 2019
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This paper presents a methodology for high ice water content (HIWC) (up to 3.5 g m−3) retrieval from a dual-polarization side-looking X-band airborne radar. Zdr and Kdp are used to mitigate the effects of ice crystal shape and orientation on the variation in IWC – specific differential phase (Kdp) joint distribution. Empirical analysis shows that the proposed method improves the estimation bias by 35 % and increases the correlation by 4 % on average, compared to the method using Kdp alone.
Shayamila Mahagammulla Gamage, Robert J. Sica, Giovanni Martucci, and Alexander Haefele
Atmos. Meas. Tech., 12, 5801–5816, https://doi.org/10.5194/amt-12-5801-2019, https://doi.org/10.5194/amt-12-5801-2019, 2019
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We present a new method for retrieving temperature from pure rotational Raman (PRR) lidar measurements using an optimal estimation method. We show that the error due to calibration can be reduced significantly using our method. The new method is tested on PRR temperature measurements from the MeteoSwiss Raman Lidar for Meteorological Observations system in different sky conditions. The next step is to assimilate the temperature profiles into models to help improve weather forecasts.
Tony Le Bastard, Olivier Caumont, Nicolas Gaussiat, and Fatima Karbou
Atmos. Meas. Tech., 12, 5669–5684, https://doi.org/10.5194/amt-12-5669-2019, https://doi.org/10.5194/amt-12-5669-2019, 2019
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The estimation of surface rainfall from radars becomes less effective at long ranges or in mountainous regions where the radar beam is far from the ground. The method proposed in this paper investigates how vertical profiles simulated from high-resolution model can be used to predict the evolution of the precipitation below the radar beam. Our results show that this novel method leads to better results than the current operational methods that either use climatological or idealised profiles.
Guang Wen, Neil I. Fox, and Patrick S. Market
Atmos. Meas. Tech., 12, 5613–5637, https://doi.org/10.5194/amt-12-5613-2019, https://doi.org/10.5194/amt-12-5613-2019, 2019
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In this study, we propose a probabilistic method based on the Gaussian mixture model to estimate the slope of a data profile. The Gaussian mixture method (GMM) not only obtains the expected value of the slope by differentiating the conditional expectation of the data, but also yields the variance of the slope regarding the errors in the calculation of the first derivative.
Jordi Figueras i Ventura, Nicolau Pineda, Nikola Besic, Jacopo Grazioli, Alessandro Hering, Oscar A. van der Velde, David Romero, Antonio Sunjerga, Amirhossein Mostajabi, Mohammad Azadifar, Marcos Rubinstein, Joan Montanyà, Urs Germann, and Farhad Rachidi
Atmos. Meas. Tech., 12, 5573–5591, https://doi.org/10.5194/amt-12-5573-2019, https://doi.org/10.5194/amt-12-5573-2019, 2019
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This paper presents an analysis of the lightning production of convective cells. Polarimetric weather radar data were used to identify and characterize the convective cells while lightning was detected using the EUCLID network and a lightning mapping array deployed during the summer of 2017 in the northeastern part of Switzerland. In it we show that there is a good correlation between the height of the rimed-particle column and the intensity of the lightning activity in the convective cell.
Yu Shi, Fei Hu, Guangqiang Fan, and Zhe Zhang
Atmos. Meas. Tech., 12, 4887–4901, https://doi.org/10.5194/amt-12-4887-2019, https://doi.org/10.5194/amt-12-4887-2019, 2019
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In this paper, the boundary layer structure, and especially turbulence characteristics, were studied during a severe pollution episode. The data were taken from multiple observation techniques, such as lidar, wind profiler radar, radiosonde and a 325 m meteorological tower. Vertical distribution of wind and temperature, evolution of the atmospheric boundary layer (ABL) height, and turbulent flux quantities were compared and analyzed.
Katia Lamer, Bernat Puigdomènech Treserras, Zeen Zhu, Bradley Isom, Nitin Bharadwaj, and Pavlos Kollias
Atmos. Meas. Tech., 12, 4931–4947, https://doi.org/10.5194/amt-12-4931-2019, https://doi.org/10.5194/amt-12-4931-2019, 2019
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This article describes the three newly deployed second-generation radar of the Atmospheric Radiation Measurement program. Techniques to retrieve precipitation rate from their measurements are presented: noise and clutter filtering, gas and liquid attenuation correction, and radar reflectivity calibration. Rain rate for a 40 km radius domain around Graciosa estimated from all three radar differ, which highlights the need to consider sensor capabilities when interpreting radar measurements.
Natalia Hanna, Estera Trzcina, Gregor Möller, Witold Rohm, and Robert Weber
Atmos. Meas. Tech., 12, 4829–4848, https://doi.org/10.5194/amt-12-4829-2019, https://doi.org/10.5194/amt-12-4829-2019, 2019
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In the study, the potential of GNSS tomography as an important supplementary data source for numerical weather prediction models was examined. We used two GNSS tomography models (TUW, WUELS) in different configurations. The GNSS tomography outputs were assimilated into the WRF model using a radio occultation observations operator (non-standard approach). Promising results show improvement in the weather forecasting of relative humidity and temperature during heavy-precipitation events.
Nils König, Peter Braesicke, and Thomas von Clarmann
Atmos. Meas. Tech., 12, 4113–4129, https://doi.org/10.5194/amt-12-4113-2019, https://doi.org/10.5194/amt-12-4113-2019, 2019
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Inference of the tropopause from temperature profiles of finite vertical resolution entails an uncertainty of the tropopause altitude. We assess this effect by degrading the resolution of the sonde data. The tropopause altitude inferred from coarse grid profiles was found to be lower than that inferred from the original profiles for tropical and midlatitudinal radiosonde profiles. The mean displacement of the lapse rate tropopause inferred from a 3 km resolution profile is −400 m for Hilo.
Zhen Li, Ad Stoffelen, and Anton Verhoef
Atmos. Meas. Tech., 12, 3573–3594, https://doi.org/10.5194/amt-12-3573-2019, https://doi.org/10.5194/amt-12-3573-2019, 2019
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This paper presents a generic simulation rotating-beam scatterometer scheme, which includes pencil-beam and fan-beam instruments. SCAT (CFOSAT), WindRAD, and SeaWinds are chosen to represent the current or near-future rotating-beam scatterometers. Their capacity for wind retrieval and figures of merit are analyzed and compared with each other. Increasing the number of views is able to improve the wind retrieval, but the improvement also can reach saturation with even more views.
Rebecca J. Barthelmie and Sara C. Pryor
Atmos. Meas. Tech., 12, 3463–3484, https://doi.org/10.5194/amt-12-3463-2019, https://doi.org/10.5194/amt-12-3463-2019, 2019
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Wakes are volumes of air with low wind speed that form downwind of wind turbines. Their properties and behaviour determine optimal turbine spacing in wind farms. We use scanning Doppler lidar to accurately and precisely measure wake characteristics at a complex terrain site in Portugal. We develop and apply an automatic processing algorithm to detect wakes and quantify their characteristics. In higher wind speeds, the wake centres are lower. Wake centres are also lower in convective conditions.
Jordi Figueras i Ventura, Nicolau Pineda, Nikola Besic, Jacopo Grazioli, Alessandro Hering, Oscar A. van der Velde, David Romero, Antonio Sunjerga, Amirhossein Mostajabi, Mohammad Azadifar, Marcos Rubinstein, Joan Montanyà, Urs Germann, and Farhad Rachidi
Atmos. Meas. Tech., 12, 2881–2911, https://doi.org/10.5194/amt-12-2881-2019, https://doi.org/10.5194/amt-12-2881-2019, 2019
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This paper presents an analysis of a large dataset of lightning and polarimetric weather radar data collected over the course of a lightning measurement campaign that took place in the summer of 2017 in the area surrounding Säntis in northeastern Switzerland. We show that polarimetric weather radar data can be helpful in determining regions where lightning is more likely to occur, which is a first step towards a lightning nowcasting system.
Mi Liao, Sean Healy, and Peng Zhang
Atmos. Meas. Tech., 12, 2679–2692, https://doi.org/10.5194/amt-12-2679-2019, https://doi.org/10.5194/amt-12-2679-2019, 2019
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This paper describes a new method for improving the data of the Chinese radio occultation sounder, GNOS, which has large biases. The new method can effectively eliminate about 90 % of the large departures. In addition, this paper also describes the quality control (QC) for the GNOS data. The GNOS data with the new L2 extrapolation are suitable for assimilation into numerical weather prediction systems.
Brian D. Bue, David R. Thompson, Shubhankar Deshpande, Michael Eastwood, Robert O. Green, Vijay Natraj, Terry Mullen, and Mario Parente
Atmos. Meas. Tech., 12, 2567–2578, https://doi.org/10.5194/amt-12-2567-2019, https://doi.org/10.5194/amt-12-2567-2019, 2019
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Imaging spectrometers provide valuable remote measurements of Earth's surface and atmosphere. These measurements rely on computationally expensive radiative transfer models (RTMs). Spectrometers produce too much data to process with RTMs directly, requiring approximations that trade accuracy for speed. We demonstrate that neural networks can quickly emulate RTM calculations more accurately than current approaches, enabling the application of more sophisticated RTMs than current methods permit.
Mariko Oue, Pavlos Kollias, Alan Shapiro, Aleksandra Tatarevic, and Toshihisa Matsui
Atmos. Meas. Tech., 12, 1999–2018, https://doi.org/10.5194/amt-12-1999-2019, https://doi.org/10.5194/amt-12-1999-2019, 2019
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This study investigated impacts of the selected radar volume coverage pattern, the sampling time period, the number of radars used, and the added value of advection correction on the retrieval of vertical air motion from a multi-Doppler-radar technique. The results suggest that the use of rapid-scan radars can substantially improve the quality of wind retrievals and that the retrieved wind field needs to be carefully used considering the limitations of the radar observing system.
Felix Kelberlau and Jakob Mann
Atmos. Meas. Tech., 12, 1871–1888, https://doi.org/10.5194/amt-12-1871-2019, https://doi.org/10.5194/amt-12-1871-2019, 2019
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Lidars are devices that can measure wind velocities remotely from the ground. Their estimates are very accurate in the mean but wind speed fluctuations lead to measurement errors. The presented data processing methods mitigate several of the error causes: first, by making use of knowledge about the mean wind direction and, second, by determining the location of air packages and sensing them in the best moment. Both methods can be applied to existing wind lidars and results are very promising.
Máté Mile, Patrik Benáček, and Szabolcs Rózsa
Atmos. Meas. Tech., 12, 1569–1579, https://doi.org/10.5194/amt-12-1569-2019, https://doi.org/10.5194/amt-12-1569-2019, 2019
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The delay of satellite signals from the Global Navigation Satellite System is valuable for numerical weather predictions, giving useful information about atmospheric constituents. These zenith total delay observations can help to better estimate the initial state of atmospheric analyses and to improve numerical weather forecasts. This study introduces the importance of GNSS zenith total delays, the detailed observation pre-processing method and weather forecast trials.
Weihua Bai, Guojun Wang, Yueqiang Sun, Jiankui Shi, Guanglin Yang, Xiangguang Meng, Dongwei Wang, Qifei Du, Xianyi Wang, Junming Xia, Yuerong Cai, Congliang Liu, Wei Li, Chunjun Wu, Danyang Zhao, Di Wu, and Cheng Liu
Atmos. Meas. Tech., 12, 1483–1493, https://doi.org/10.5194/amt-12-1483-2019, https://doi.org/10.5194/amt-12-1483-2019, 2019
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This study reports on the application of the FY3-C GNSS occultation sounder (GNOS) for assessing the global ionospheric response to magnetic storm events. We use the March 2015 magnetic storm event to demonstrate the reliability of NmF2 data derived from the instrument through comparisons with ground-based ionosonde observations. The analysis demonstrates the reliability of the GNSS radio occultation sounding instrument GNOS aboard the FY3-C satellite and validates its ionosphere products.
Peng Jiang, Shirong Ye, Yinhao Lu, Yanyan Liu, Dezhong Chen, and Yanlan Wu
Atmos. Meas. Tech., 12, 1233–1249, https://doi.org/10.5194/amt-12-1233-2019, https://doi.org/10.5194/amt-12-1233-2019, 2019
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A time-varying global gridded Ts–Tm model with 0.75 × 0.75 degree spatial resolution is developed in our study to precisely estimate water-vapor-weighted mean temperature
Tm from surface air temperature Ts. Using multiple statistical tests, we assessed the Tm of our model and its impact on the GPS–PWV retrievals. Comparisons with other models demonstrate that our model has prominent advantages. Matlab codes and arrays used to realize our model are provided in the supplement of this study.
Juan Miguel Urco, Jorge Luis Chau, Tobias Weber, and Ralph Latteck
Atmos. Meas. Tech., 12, 955–969, https://doi.org/10.5194/amt-12-955-2019, https://doi.org/10.5194/amt-12-955-2019, 2019
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For decades, radar observations have been used to study complicated atmospheric dynamics. Previous observations of the mesosphere, between 80 and 90 km altitude, over polar regions have been limited to a spatial resolution of a few kilometers. In this work, we present a technique which allows 3-D radar observations of the mesospheric dynamics, with an unprecedented spatial resolution of ~ 900 m. We combine the concept of MIMO and high-resolution algorithms to improve the spatial resolution.
Lukas Krasauskas, Jörn Ungermann, Stefan Ensmann, Isabell Krisch, Erik Kretschmer, Peter Preusse, and Martin Riese
Atmos. Meas. Tech., 12, 853–872, https://doi.org/10.5194/amt-12-853-2019, https://doi.org/10.5194/amt-12-853-2019, 2019
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Many limb sounder measurements from the same atmospheric region taken at different angles can be combined into a 3-D tomographic image of the atmosphere. Mathematically, this is a complex, computationally expensive, underdetermined problem that needs additional constraints (regularisation). We introduce an improved regularisation method based on physical properties of the atmosphere with a new irregular grid implementation. Simulated data tests show improved results and lower computational cost.
Ville Vakkari, Antti J. Manninen, Ewan J. O'Connor, Jan H. Schween, Pieter G. van Zyl, and Eleni Marinou
Atmos. Meas. Tech., 12, 839–852, https://doi.org/10.5194/amt-12-839-2019, https://doi.org/10.5194/amt-12-839-2019, 2019
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Commercially available Doppler lidars have been proven to be efficient tools for studying winds and turbulence in the planetary boundary layer. However, in many cases low signal is still a limiting factor for utilising measurements by these devices. Here, we present a novel post-processing algorithm for Halo Stream Line Doppler lidars, which enables an improvement in sensitivity of a factor of 5 or more.
Alain Hauchecorne, Laurent Blanot, Robin Wing, Philippe Keckhut, Sergey Khaykin, Jean-Loup Bertaux, Mustapha Meftah, Chantal Claud, and Viktoria Sofieva
Atmos. Meas. Tech., 12, 749–761, https://doi.org/10.5194/amt-12-749-2019, https://doi.org/10.5194/amt-12-749-2019, 2019
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This paper presents a new dataset of temperature profiles in the upper stratosphere and mesosphere acquired with the GOMOS spectrometer on board the European satellite ENVISAT. The principle is to observe the scattering of sunlight by air molecules at the Earth limb. The observed signal is proportional to the atmospheric density from which the temperature is derived. This technique provides a new source of information on temperature where satellite observations are sparse.
Viktoria F. Sofieva, Francis Dalaudier, Alain Hauchecorne, and Valery Kan
Atmos. Meas. Tech., 12, 585–598, https://doi.org/10.5194/amt-12-585-2019, https://doi.org/10.5194/amt-12-585-2019, 2019
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This paper describes the temperature profiles in the stratosphere obtained from unique stellar scintillation measurements by the GOMOS instrument operated on board Envisat in 2002–2012. The high-resolution temperature profiles (HRTPs) are retrieved with a very good vertical resolution of ~ 200 m and a high accuracy of ~ 1–3 K for altitudes 15–32 km as well as a global coverage. HRTPs can be assimilated into atmospheric models and used in analyses of internal gravity wave activity.
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Short summary
The discrimination between meteorological and non-meteorological echoes is necessary to obtain better meteorological application performance. However, the widely used algorithms have high expectations for polarimetric data, which have similar characteristics between meteorological and non-meteorological echoes in the weak-signal regions. Therefore, an improved fuzzy logic method is proposed in this paper to improve the classification performance in weak-signal regions.
The discrimination between meteorological and non-meteorological echoes is necessary to obtain...
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