Articles | Volume 15, issue 3
https://doi.org/10.5194/amt-15-811-2022
© Author(s) 2022. 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-15-811-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
15 Feb 2022
Research article |
| 15 Feb 2022
| 15 Feb 2022
Characterizing and correcting the warm bias observed in Aircraft Meteorological Data Relay (AMDAR) temperature observations
Siebren de Haan
CORRESPONDING AUTHOR
Royal Netherlands Meteorological Institute (KNMI), Utrechtseweg 297, 3731 GA De Bilt, the Netherlands
Paul M. A. de Jong
Royal Netherlands Meteorological Institute (KNMI), Utrechtseweg 297, 3731 GA De Bilt, the Netherlands
Jitze van der Meulen
Royal Netherlands Meteorological Institute (KNMI), Utrechtseweg 297, 3731 GA De Bilt, the Netherlands
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Siebren de Haan, Paul de Jong, Michal Koutek, and Jan Sondij
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-110, https://doi.org/10.5194/amt-2024-110, 2024
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This manscript describes the operational method of extracting meteorological information from all airborne aircraft in the European airspace every 20 seconds to 1 minute. The methodology is described and the quality of the wind and temperature observations are evaluated against radiosonde observations.
Guergana Guerova, Jonathan Jones, Jan Douša, Galina Dick, Siebren de Haan, Eric Pottiaux, Olivier Bock, Rosa Pacione, Gunnar Elgered, Henrik Vedel, and Michael Bender
Atmos. Meas. Tech., 9, 5385–5406, https://doi.org/10.5194/amt-9-5385-2016, https://doi.org/10.5194/amt-9-5385-2016, 2016
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Application of global navigation satellite systems (GNSSs) for atmospheric remote sensing (GNSS meteorology) is a well-established field in both research and operation in Europe. This review covers the state of the art in GNSS meteorology in Europe. It discusses 1) advances in GNSS processing techniques and tropospheric products, 2) use in numerical weather prediction and nowcasting, and 3) climate research.
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Atmos. Meas. Tech., 9, 4141–4150, https://doi.org/10.5194/amt-9-4141-2016, https://doi.org/10.5194/amt-9-4141-2016, 2016
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The paper presents estimates of aircraft-derived wind observations obtained using Mode-S EHS method by applying the triple-collocation technique. Triple-collocated data sets were constructed using sodar (at Schiphol airport) and Doppler radar wind observation (from two radars in the Netherlands) in combination with numerical weather model data. It was found that the wind error near the surface is around 1.4 m s−1, while at 500 hPa the error is estimated to be around 1.1 m s−1.
Jacek M. Kopeć, Kamil Kwiatkowski, Siebren de Haan, and Szymon P. Malinowski
Atmos. Meas. Tech., 9, 2253–2265, https://doi.org/10.5194/amt-9-2253-2016, https://doi.org/10.5194/amt-9-2253-2016, 2016
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This paper is presenting a feasibility study focused on methods of estimating the turbulence intensity based on a class of navigational messages routinely broadcast by the commercial aircraft (known as ADS-B and Mode-S). Using this kind of information could have potentially significant impact on aviation safety. Three methods have been investigated.
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Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-110, https://doi.org/10.5194/amt-2024-110, 2024
Preprint under review for AMT
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This manscript describes the operational method of extracting meteorological information from all airborne aircraft in the European airspace every 20 seconds to 1 minute. The methodology is described and the quality of the wind and temperature observations are evaluated against radiosonde observations.
Guergana Guerova, Jonathan Jones, Jan Douša, Galina Dick, Siebren de Haan, Eric Pottiaux, Olivier Bock, Rosa Pacione, Gunnar Elgered, Henrik Vedel, and Michael Bender
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Application of global navigation satellite systems (GNSSs) for atmospheric remote sensing (GNSS meteorology) is a well-established field in both research and operation in Europe. This review covers the state of the art in GNSS meteorology in Europe. It discusses 1) advances in GNSS processing techniques and tropospheric products, 2) use in numerical weather prediction and nowcasting, and 3) climate research.
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Atmos. Meas. Tech., 9, 4141–4150, https://doi.org/10.5194/amt-9-4141-2016, https://doi.org/10.5194/amt-9-4141-2016, 2016
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The paper presents estimates of aircraft-derived wind observations obtained using Mode-S EHS method by applying the triple-collocation technique. Triple-collocated data sets were constructed using sodar (at Schiphol airport) and Doppler radar wind observation (from two radars in the Netherlands) in combination with numerical weather model data. It was found that the wind error near the surface is around 1.4 m s−1, while at 500 hPa the error is estimated to be around 1.1 m s−1.
Jacek M. Kopeć, Kamil Kwiatkowski, Siebren de Haan, and Szymon P. Malinowski
Atmos. Meas. Tech., 9, 2253–2265, https://doi.org/10.5194/amt-9-2253-2016, https://doi.org/10.5194/amt-9-2253-2016, 2016
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This paper is presenting a feasibility study focused on methods of estimating the turbulence intensity based on a class of navigational messages routinely broadcast by the commercial aircraft (known as ADS-B and Mode-S). Using this kind of information could have potentially significant impact on aviation safety. Three methods have been investigated.
Related subject area
Subject: Others (Wind, Precipitation, Temperature, etc.) | Technique: In Situ Measurement | Topic: Validation and Intercomparisons
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Jérôme Kopp, Agostino Manzato, Alessandro Hering, Urs Germann, and Olivia Martius
Atmos. Meas. Tech., 16, 3487–3503, https://doi.org/10.5194/amt-16-3487-2023, https://doi.org/10.5194/amt-16-3487-2023, 2023
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We present the first study of extended field observations made by a network of 80 automatic hail sensors from Switzerland. The sensors record the exact timing of hailstone impacts, providing valuable information about the local duration of hailfall. We found that the majority of hailfalls lasts just a few minutes and that most hailstones, including the largest, fall during a first phase of high hailstone density, while a few remaining and smaller hailstones fall in a second low-density phase.
Najmeh Kaffashzadeh
Atmos. Meas. Tech., 16, 3085–3100, https://doi.org/10.5194/amt-16-3085-2023, https://doi.org/10.5194/amt-16-3085-2023, 2023
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Although quality control is a well-known issue in data application, research initiatives and organizations apply given methods based on traditional techniques (ad hoc thresholds and manual). These approaches are not only error prone but also unsuitable for a large volume of data. The method proposed in this paper is based on a new concept (probability) as an intuitive indicator and data’s characteristics, which leads it to be applicable to a wide variety of data and eases its
fit for purpose.
Charles Nelson Helms, Stephen Joseph Munchak, Ali Tokay, and Claire Pettersen
Atmos. Meas. Tech., 15, 6545–6561, https://doi.org/10.5194/amt-15-6545-2022, https://doi.org/10.5194/amt-15-6545-2022, 2022
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This study compares the techniques used to measure snowflake shape by three instruments: PIP, MASC, and 2DVD. Our findings indicate that the MASC technique produces reliable shape measurements; the 2DVD technique performs better than expected considering the instrument was designed to measure raindrops; and the PIP technique does not produce reliable snowflake shape measurements. We also demonstrate that the PIP images can be reprocessed to correct the shape measurement issues.
Shunsuke Hoshino, Takuji Sugidachi, Kensaku Shimizu, Eriko Kobayashi, Masatomo Fujiwara, and Masami Iwabuchi
Atmos. Meas. Tech., 15, 5917–5948, https://doi.org/10.5194/amt-15-5917-2022, https://doi.org/10.5194/amt-15-5917-2022, 2022
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GRUAN data products (GDPs) from Meisei iMS-100 and Vaisala RS92 were compared with 59 dual sounding data. For daytime observations, the iMS-100 temperature is around 0.5 K lower than RS92-GDP in the stratosphere, but for nighttime observations, the difference is around −0.1 K, and data are mostly in agreement. For relative humidity (RH), iMS-100 is around 1–2 % RH higher in the troposphere and 1 % RH smaller in the stratosphere than RS92, but both GDPs are in agreement for most of the profile.
Chih-Chun Chou, Paul J. Kushner, Stéphane Laroche, Zen Mariani, Peter Rodriguez, Stella Melo, and Christopher G. Fletcher
Atmos. Meas. Tech., 15, 4443–4461, https://doi.org/10.5194/amt-15-4443-2022, https://doi.org/10.5194/amt-15-4443-2022, 2022
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Aeolus is the first satellite that provides global wind profile measurements. The mission aims to improve the weather forecasts in the tropics, but also, potentially, in the polar regions. We evaluate the performance of the instrument over the Canadian North and the Arctic by comparing its measured winds in both cloudy and non-cloudy layers to wind data from forecasts, reanalysis, and ground-based instruments. Overall, good agreement was seen, but Aeolus winds have greater dispersion.
Victoria Anne Sinclair, Jenna Ritvanen, Gabin Urbancic, Irene Erner, Yurii Batrak, Dmitri Moisseev, and Mona Kurppa
Atmos. Meas. Tech., 15, 3075–3103, https://doi.org/10.5194/amt-15-3075-2022, https://doi.org/10.5194/amt-15-3075-2022, 2022
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We investigate the boundary-layer (BL) height and surface stability in southern Finland using radiosondes, a microwave radiometer and ERA5 reanalysis. Accurately quantifying the BL height is challenging, and the diagnosed BL height can depend strongly on the method used. Microwave radiometers provide reliable estimates of the BL height but only in unstable conditions. ERA5 captures the BL height well except under very stable conditions, which occur most commonly at night during the warm season.
Didier de Villiers, Marc Schleiss, Marie-Claire ten Veldhuis, Rolf Hut, and Nick van de Giesen
Atmos. Meas. Tech., 14, 5607–5623, https://doi.org/10.5194/amt-14-5607-2021, https://doi.org/10.5194/amt-14-5607-2021, 2021
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Ground-based rainfall observations across the African continent are sparse. We present a new and inexpensive rainfall measuring instrument (the intervalometer) and use it to derive reasonably accurate rainfall rates. These are dependent on a fundamental assumption that is widely used in parameterisations of the rain drop size distribution. This assumption is tested and found to not apply for most raindrops but is still useful in deriving rainfall rates. The intervalometer shows good potential.
Olli Peltola, Karl Lapo, Ilkka Martinkauppi, Ewan O'Connor, Christoph K. Thomas, and Timo Vesala
Atmos. Meas. Tech., 14, 2409–2427, https://doi.org/10.5194/amt-14-2409-2021, https://doi.org/10.5194/amt-14-2409-2021, 2021
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We evaluated the suitability of fiber-optic distributed temperature sensing (DTS) for observing spatial (>25 cm) and temporal (>1 s) details of airflow within and above forests. The DTS measurements could discern up to third-order moments of the flow and observe spatial details of coherent flow motions. Similar measurements are not possible with more conventional measurement techniques. Hence, the DTS measurements will provide key insights into flows close to roughness elements, e.g. trees.
Anne Martin, Martin Weissmann, Oliver Reitebuch, Michael Rennie, Alexander Geiß, and Alexander Cress
Atmos. Meas. Tech., 14, 2167–2183, https://doi.org/10.5194/amt-14-2167-2021, https://doi.org/10.5194/amt-14-2167-2021, 2021
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This study provides an overview of validation activities to determine the Aeolus HLOS wind errors and to understand the biases by investigating possible dependencies and testing bias correction approaches. To ensure meaningful validation statistics, collocated radiosondes and two different global NWP models, the ECMWF IFS and the ICON model (DWD), are used as reference data. To achieve an estimate for the Aeolus instrumental error the representativeness errors for the comparisons are evaluated.
Rumeng Li, Qinghong Zhang, Juanzhen Sun, Yun Chen, Lili Ding, and Tian Wang
Atmos. Meas. Tech., 14, 785–801, https://doi.org/10.5194/amt-14-785-2021, https://doi.org/10.5194/amt-14-785-2021, 2021
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In this paper, we describe a bias-correction method based on machine learning without the need to obtain users' personal information and demonstrate that the method can effectively reduce the bias in smartphone pressure observations. The characteristics of this dataset are discussed, and the potential application of the bias-corrected data is illustrated by the fine-scale analysis of a hailstorm that occurred on 10 June 2016 in Beijing, China.
Michael Fehlmann, Mario Rohrer, Annakaisa von Lerber, and Markus Stoffel
Atmos. Meas. Tech., 13, 4683–4698, https://doi.org/10.5194/amt-13-4683-2020, https://doi.org/10.5194/amt-13-4683-2020, 2020
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The Thies disdrometer is used to monitor precipitation intensity and its phase and thus may provide valuable information for the management of meteorological and hydrological risks. In this study, we characterize biases of this instrument using common reference instruments at a pre-alpine study site in Switzerland. We find a systematic underestimation of liquid precipitation amounts and suggest possible reasons for and corrections to this bias and relate these findings to other study sites.
Adam Theisen, Max Ungar, Bryan Sheridan, and Bradley G. Illston
Atmos. Meas. Tech., 13, 4699–4713, https://doi.org/10.5194/amt-13-4699-2020, https://doi.org/10.5194/amt-13-4699-2020, 2020
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A low-cost weather station with 3D-printed components was built, based on the UCAR 3D-PAWS project, and deployed alongside an Oklahoma Mesonet station for an 8-month study to determine the longevity of these sensors and their performance compared with standard commercial sensors. Results show that the low-cost sensors can perform as well as the more expensive commercial ones for short-term deployments with the possibility for long-term deployments with proper maintenance and replacement.
Boming Liu, Jianping Guo, Wei Gong, Lijuan Shi, Yong Zhang, and Yingying Ma
Atmos. Meas. Tech., 13, 4589–4600, https://doi.org/10.5194/amt-13-4589-2020, https://doi.org/10.5194/amt-13-4589-2020, 2020
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Vertical wind profiles are crucial to a wide range of atmospheric disciplines. However, the wind profile across China remains poorly understood. Here we reveal the salient features of winds from the radar wind profile of China, including the main instruments, spatial coverage and sampling frequency. This work is expected to allow the public and scientific community to be more familiar with the nationwide network and encourage the use of these valuable data in future research and applications.
Tyler M. Bell, Brian R. Greene, Petra M. Klein, Matthew Carney, and Phillip B. Chilson
Atmos. Meas. Tech., 13, 3855–3872, https://doi.org/10.5194/amt-13-3855-2020, https://doi.org/10.5194/amt-13-3855-2020, 2020
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It is well known that the atmospheric boundary layer is under-sampled in the vertical dimension. Recently, weather-sensing uncrewed aerial systems (WxUAS) have created new opportunities to sample this region of the atmosphere. This study compares a WxUAS developed at the University of Oklahoma to ground-based remote sensing and radiosondes. We find that overall the systems generally agreed well both thermodynamically and kinematically. However, there is still room to improve each system.
Hubert Luce and Hiroyuki Hashiguchi
Atmos. Meas. Tech., 13, 1989–1999, https://doi.org/10.5194/amt-13-1989-2020, https://doi.org/10.5194/amt-13-1989-2020, 2020
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Vertical ascent rate Vb of meteorological balloons is sometimes used for retrieving vertical air velocity, an important parameter for meteorological applications. Comparisons with concurrent radar and unmanned aerial vehicle (UAV) measurements of atmospheric turbulence showed that Vb can be increased in turbulent layers due to the probable decrease in the drag coefficient of the balloon. We conclude that Vb can also potentially be used for the detection of atmospheric turbulence.
Matthias Mauder, Michael Eggert, Christian Gutsmuths, Stefan Oertel, Paul Wilhelm, Ingo Voelksch, Luise Wanner, Jens Tambke, and Ivan Bogoev
Atmos. Meas. Tech., 13, 969–983, https://doi.org/10.5194/amt-13-969-2020, https://doi.org/10.5194/amt-13-969-2020, 2020
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Sonic anemometers are prone to probe-induced flow distortion effects. Here, we present the results of an intercomparison experiment between a CSAT3B sonic anemometer and a high-resolution bistatic Doppler lidar, which is inherently free of flow distortion. Our results show an agreement of the mean wind velocity measurements and the standard deviations of the vertical wind speed with comparabilities of 0.082 and 0.020 m s−1, respectively. Friction velocity is underestimated by the CSAT3B by 3 %.
Tara Hanlon and David Risk
Atmos. Meas. Tech., 13, 191–203, https://doi.org/10.5194/amt-13-191-2020, https://doi.org/10.5194/amt-13-191-2020, 2020
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In this study, we aimed to improve accuracy of wind speed and direction measurements from an anemometer mounted atop a research vehicle. Controlled field tests and computer simulations showed that the vehicle shape biases airflow above the vehicle. The results indicate that placing an anemometer at a significant height (> 1 m) above the vehicle, and calibrating anemometer measurements for vehicle shape and wind angle, can be effective in reducing bias in measurements of wind speed and direction.
Eriko Kobayashi, Shunsuke Hoshino, Masami Iwabuchi, Takuji Sugidachi, Kensaku Shimizu, and Masatomo Fujiwara
Atmos. Meas. Tech., 12, 3039–3065, https://doi.org/10.5194/amt-12-3039-2019, https://doi.org/10.5194/amt-12-3039-2019, 2019
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The authors carried out dual flights of RS-11G and RS92-SGP radiosondes and investigated the differences in the performance of the radiosondes to help characterize GRUAN data products. A novel aspect of GRUAN data products is that vertically resolved uncertainty estimates and metadata are provided for each sounding and comparison of GRUAN data products is important in securing the temporal homogeneity of climate data records.
Alfredo Peña, Ebba Dellwik, and Jakob Mann
Atmos. Meas. Tech., 12, 237–252, https://doi.org/10.5194/amt-12-237-2019, https://doi.org/10.5194/amt-12-237-2019, 2019
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We propose a method to assess the accuracy of turbulence measurements by sonic anemometers. The idea is to compute the ratio of the vertical to along-wind velocity spectrum within the inertial subrange. We found that the Metek USA-1 and the Campbell CSAT3 sonic anemometers do not show the expected theoretical ratio. A wind-tunnel-based correction recovers the expected ratio for the USA-1. A correction for the CSAT3 does not, illustrating that this sonic anemometer suffers from flow distortion.
Fabien Carminati, Stefano Migliorini, Bruce Ingleby, William Bell, Heather Lawrence, Stuart Newman, James Hocking, and Andrew Smith
Atmos. Meas. Tech., 12, 83–106, https://doi.org/10.5194/amt-12-83-2019, https://doi.org/10.5194/amt-12-83-2019, 2019
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The GRUAN processor is a software developed to collocate radiosonde profiles and numerical weather prediction model fields, simulate top-of-atmosphere brightness temperature at frequencies used by space-borne instruments, and propagate the radiosonde uncertainties in that simulation. This work responds to an identified lack of metrologically traceable characterisation of uncertainties in model fields that are increasingly used for the validation and calibration of space-borne instruments.
Fenghua Zhou, Rongwang Zhang, Rui Shi, Ju Chen, Yunkai He, Dongxiao Wang, and Qiang Xie
Atmos. Meas. Tech., 11, 6091–6106, https://doi.org/10.5194/amt-11-6091-2018, https://doi.org/10.5194/amt-11-6091-2018, 2018
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In this work, successive air–sea heat flux-related data were acquired over the course of a year (01/02/2016–31/01/2017) at the YXASFT on Yongxing Island. Then, seasonal comparisons were conducted for the daily mean surface bulk variables and heat fluxes between the WHOI OAFlux products and YXASFT observations. The conclusions in this paper will provide useful reference for researchers on how to select the appropriate OAFlux datasets in different seasons over the South China Sea.
Dong-Kyun Kim and Chang-Keun Song
Atmos. Meas. Tech., 11, 3851–3860, https://doi.org/10.5194/amt-11-3851-2018, https://doi.org/10.5194/amt-11-3851-2018, 2018
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A new technique to estimate vertical velocities from Parsivel-measured drop and velocity spectra is developed. The estimated vertical velocities (w) were compared with w components of winds measured from the anemometer at the same site. They showed good agreement with each other, suggesting that this technique is reliable and applicable to rainfall studies. With these w values, rainfall characteristics related to up-/downdraft were investigated on the windward and leeward sides of a mountain.
Gerald M. Lohmann and Adam H. Monahan
Atmos. Meas. Tech., 11, 3131–3144, https://doi.org/10.5194/amt-11-3131-2018, https://doi.org/10.5194/amt-11-3131-2018, 2018
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Using high-resolution surface irradiance data with original temporal resolutions between 0.01 s and 1 s from six different locations in the Northern Hemisphere, we characterize the changes in representation of temporal variability resulting from time averaging. Our results indicate that a temporal averaging time scale of around 1 s marks a transition in representing single-point irradiance variability, such that longer averages result in substantial underestimates of variability.
Astrid Lampert, Jörg Hartmann, Falk Pätzold, Lennart Lobitz, Peter Hecker, Katrin Kohnert, Eric Larmanou, Andrei Serafimovich, and Torsten Sachs
Atmos. Meas. Tech., 11, 2523–2536, https://doi.org/10.5194/amt-11-2523-2018, https://doi.org/10.5194/amt-11-2523-2018, 2018
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We compared two different fast-response humidity sensors simultaneously on different airborne platforms. One is a particular, well-establed Lyman-alpha hygrometer that has been used for decades as the standard for fast airborne humidity measurements. However, it is not available any more. The other one is a hygrometer based on the absorption of infrared radiation, from LI-COR. For an environment of low vibrations, the LI-COR sensor is suitable for fast airborne water vapour measurements.
Nicholas Zelasko, Adam Wettlaufer, Bujidmaa Borkhuu, Matthew Burkhart, Leah S. Campbell, W. James Steenburgh, and Jefferson R. Snider
Atmos. Meas. Tech., 11, 441–458, https://doi.org/10.5194/amt-11-441-2018, https://doi.org/10.5194/amt-11-441-2018, 2018
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The hotplate precipitation gauge has the potential to solve some problems with conventional precipitation gauge measurements, especially for snowfall. This paper extends the seminal published work, Rasmussen et al. (2011). We assert that the precipitation rate algorithm we have developed for the hotplate is an improvement on that which was previously published.
Matthias Mauder and Matthias J. Zeeman
Atmos. Meas. Tech., 11, 249–263, https://doi.org/10.5194/amt-11-249-2018, https://doi.org/10.5194/amt-11-249-2018, 2018
William Wandji Nyamsi, Mikko R. A. Pitkänen, Youva Aoun, Philippe Blanc, Anu Heikkilä, Kaisa Lakkala, Germar Bernhard, Tapani Koskela, Anders V. Lindfors, Antti Arola, and Lucien Wald
Atmos. Meas. Tech., 10, 4965–4978, https://doi.org/10.5194/amt-10-4965-2017, https://doi.org/10.5194/amt-10-4965-2017, 2017
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This paper proposes a new, fast and accurate method for estimating UV fluxes at ground level in cloud-free conditions at any place and time. The method performs very well with the Copernicus Atmosphere Monitoring Service products as inputs describing the state of the atmosphere. An accuracy that is close to the uncertainty of the measurements themselves is reached. We believe that our research will be widely used in the near future.
Hannah K. Huelsing, Junhong Wang, Carl Mears, and John J. Braun
Atmos. Meas. Tech., 10, 4055–4066, https://doi.org/10.5194/amt-10-4055-2017, https://doi.org/10.5194/amt-10-4055-2017, 2017
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The precipitable water (PW) was examined for the 2013 Colorado flood to determine how climatologically abnormal this event was. The seasonal PW maximum extended into early September and the September monthly mean PW exceeded the 99th percentile of climatology with a value 25% higher than the 40-year climatology. The above-normal, near-saturation PW values during the flood were the result of large-scale moisture transport into Colorado from the eastern tropical Pacific and the Gulf of Mexico.
Yoshimi Kawai, Masaki Katsumata, Kazuhiro Oshima, Masatake E. Hori, and Jun Inoue
Atmos. Meas. Tech., 10, 2485–2498, https://doi.org/10.5194/amt-10-2485-2017, https://doi.org/10.5194/amt-10-2485-2017, 2017
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The model RS92 radiosonde manufactured by Vaisala Ltd. is now being replaced with a successor model, the RS41, and we need to clarify accuracy differences between them for a variety of research. For this purpose, 36 twin-radiosonde flights were performed over the oceans from the Arctic to the tropics. Basically the differences between the RS41 and RS92 were smaller than the nominal combined uncertainties of the RS41; however, we found non-negligible biases in relative humidity and pressure.
Stefano Federico, Rosa Claudia Torcasio, Paolo Sanò, Daniele Casella, Monica Campanelli, Jan Fokke Meirink, Ping Wang, Stefania Vergari, Henri Diémoz, and Stefano Dietrich
Atmos. Meas. Tech., 10, 2337–2352, https://doi.org/10.5194/amt-10-2337-2017, https://doi.org/10.5194/amt-10-2337-2017, 2017
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In this paper we evaluate the performance of two estimates of the global horizontal irradiance (GHI), one derived from the Meteosat Second Generation and one from a meteorological model (Regional Atmospheric Modeling System) forecast. The focus area is Italy, and the performance is evaluated for 12 pyranometers spanning a range of climate conditions, from Mediterranean maritime to Alpine.
Armin Sigmund, Lena Pfister, Chadi Sayde, and Christoph K. Thomas
Atmos. Meas. Tech., 10, 2149–2162, https://doi.org/10.5194/amt-10-2149-2017, https://doi.org/10.5194/amt-10-2149-2017, 2017
Dietmar J. Baumgartner, Werner Pötzi, Heinrich Freislich, Heinz Strutzmann, Astrid M. Veronig, and Harald E. Rieder
Atmos. Meas. Tech., 10, 1181–1190, https://doi.org/10.5194/amt-10-1181-2017, https://doi.org/10.5194/amt-10-1181-2017, 2017
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In this work we present KSO-STREAMS (KSO-SunTRackEr Accuracy Monitoring System), a platform-independent, fully automated, and cost-effective system to evaluate the pointing accuracy of Sun-tracking devices as well as its application at the Kanzelhöhe Observatory (KSO) Austrian radiation monitoring network (ARAD) site and to the results from a 15-week evaluating period.
Samuel T. Buisán, Michael E. Earle, José Luís Collado, John Kochendorfer, Javier Alastrué, Mareile Wolff, Craig D. Smith, and Juan I. López-Moreno
Atmos. Meas. Tech., 10, 1079–1091, https://doi.org/10.5194/amt-10-1079-2017, https://doi.org/10.5194/amt-10-1079-2017, 2017
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Within the framework of the WMO-SPICE (Solid Precipitation Intercomparison Experiment) the Thies tipping bucket precipitation gauge, widely used at AEMET, was assessed against the SPICE reference.
Most countries use tipping buckets and for this reason the underestimation of snowfall precipitation is a large-scale problem.
The methodology presented here can be used by other national weather services to test precipitation bias corrections and to identify regions where errors are higher.
Rosa Delia García, Emilio Cuevas, Omaira Elena García, Ramón Ramos, Pedro Miguel Romero-Campos, Fernado de Ory, Victoria Eugenia Cachorro, and Angel de Frutos
Atmos. Meas. Tech., 10, 731–743, https://doi.org/10.5194/amt-10-731-2017, https://doi.org/10.5194/amt-10-731-2017, 2017
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A 1-year intercomparison of classical and modern radiation and sunshine duration instruments has been performed at Izaña Atmospheric Observatory. We compare global solar radiation (GSR) records measured with a Kipp & Zonen CM-21 pyranometer, taken in the framework of the Baseline Surface Radiation Network, with those measured with a multifilter rotating shadowband radiometer and a bimetallic pyranometer, and with GSR estimated from sunshine duration performed with a CS sunshine recorder.
Wengang Zhang, Guirong Xu, Yuanyuan Liu, Guopao Yan, Dejun Li, and Shengbo Wang
Atmos. Meas. Tech., 10, 155–165, https://doi.org/10.5194/amt-10-155-2017, https://doi.org/10.5194/amt-10-155-2017, 2017
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A comparison between a microwave radiometer and radiosonde is carried out, and performances of zenith and off-zenith observations during snowfall are shown. In off-zenith observations, the effect of snow is obviously mitigated, and the deviation between microwave radiometer and radiosonde is small. With the aid of off-zenith observation, reliable thermodynamic atmospheric profiles can be collected, and those will be useful for the analysis and forecasting of severe convective weather.
Mattia Stagnaro, Matteo Colli, Luca Giovanni Lanza, and Pak Wai Chan
Atmos. Meas. Tech., 9, 5699–5706, https://doi.org/10.5194/amt-9-5699-2016, https://doi.org/10.5194/amt-9-5699-2016, 2016
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The research presented in this work involves field data analysis, numerical modelling techniques and approaches to a long-standing problem of liquid precipitation measurements: the sampling and the interpretation of the tipping-bucket sensor signal. The present study shows relevant implications of the adopted data processing methods for the accuracy of the rainfall intensity measurements provided by traditional tipping-bucket gauges.
Michael P. Jensen, Donna J. Holdridge, Petteri Survo, Raisa Lehtinen, Shannon Baxter, Tami Toto, and Karen L. Johnson
Atmos. Meas. Tech., 9, 3115–3129, https://doi.org/10.5194/amt-9-3115-2016, https://doi.org/10.5194/amt-9-3115-2016, 2016
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An intercomparison of Vaisala's latest-generation radiosonde RS41 and the widely used RS92 was performed in north-central Oklahoma, USA, during June 2014. The results indicate that for the conditions observed during the intercomparison the measurements of pressure, temperature, humidity, and winds agree to within the manufacturer-specified combined uncertainties. Some important exceptions were noted when exiting liquid cloud layers where evaporative cooling has less impact for RS41 measurements.
Karl Bumke, Gert König-Langlo, Julian Kinzel, and Marc Schröder
Atmos. Meas. Tech., 9, 2409–2423, https://doi.org/10.5194/amt-9-2409-2016, https://doi.org/10.5194/amt-9-2409-2016, 2016
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Satellite-derived HOAPS and ERA-Interim reanalysis data were validated against shipboard precipitation measurements. Results show that HOAPS detects the frequency of precipitation well, while ERA-Interim strongly overestimates it, especially at low latitudes. However, HOAPS underestimates precipitation rates, while ERA-Interim's Atlantic-wide precipitation rate is close to measurements. ERA-Interim strongly overestimates it in the intertropical convergence zone and southern subtropics.
Luca Egli, Julian Gröbner, Gregor Hülsen, Luciano Bachmann, Mario Blumthaler, Jimmy Dubard, Marina Khazova, Richard Kift, Kees Hoogendijk, Antonio Serrano, Andrew Smedley, and José-Manuel Vilaplana
Atmos. Meas. Tech., 9, 1553–1567, https://doi.org/10.5194/amt-9-1553-2016, https://doi.org/10.5194/amt-9-1553-2016, 2016
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Array spectroradiometers are small, light, robust and cost-effective instruments, and are increasingly used for atmospheric measurements. The quality of array spectroradiometers is assessed for the reliable quantification of ultraviolet radiation (UV) in order to monitor the exposure of UV radiation to human health. The study shows that reliable UV measurements with these instruments are limited for observations around noon and show large biases in the morning and evening.
K.-L. Chang, S. Guillas, and V. E. Fioletov
Atmos. Meas. Tech., 8, 4487–4505, https://doi.org/10.5194/amt-8-4487-2015, https://doi.org/10.5194/amt-8-4487-2015, 2015
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The aim of this article is to analyze the total column ozone data from the World Ozone and Ultraviolet Radiation Data Centre (WOUDC) that consists of around 150 stations irregularly spaced over the globe. Our use of a new statistical spatial technique over the globe can greatly outperform the currently used spatial approximation of the total column ozone in terms of approximation. We feel that this technique could benefit the ozone science community.
A. K. Vance, S. J. Abel, R. J. Cotton, and A. M. Woolley
Atmos. Meas. Tech., 8, 1617–1625, https://doi.org/10.5194/amt-8-1617-2015, https://doi.org/10.5194/amt-8-1617-2015, 2015
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Comparisons on the FAAM BAe 146-301 aircraft show good agreement between chilled mirror hygrometers and a WVSS-II fed from a modified Rosemount inlet (wvssR) in coud-free conditions, but a WVSS-II fed from the standard flush inlet (wvssF) over-reads, except at higher humidities. Case studies in cloudy conditions show that wvssF is immune to liquid water and ice, whilst wvssR is susceptible to both. Both WVSS-II inlets respond much more rapidly than the chilled mirror devices, especially wvssF.
Cited articles
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Short summary
AMDAR temperatures suffer from a bias, which can be related to a difference in the timing of height and measurement and to internal corrections applied to pressure altitude. Based on NWP model temperature data, combined with Mach number and true airspeed, we could estimate corrections. Comparing corrected temperatures with (independent) radiosonde observations demonstrates a reduction in the bias, from 0.5 K to around zero, and standard deviation, of almost 10 %.
AMDAR temperatures suffer from a bias, which can be related to a difference in the timing of...
