Articles | Volume 10, issue 9
https://doi.org/10.5194/amt-10-3375-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/amt-10-3375-2017
© Author(s) 2017. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
15 Sep 2017
Research article |
| 15 Sep 2017
The high-resolution extraterrestrial solar spectrum (QASUMEFTS) determined from ground-based solar irradiance measurements
Julian Gröbner
CORRESPONDING AUTHOR
Physikalisch-Meteorologisches Observatorium Davos, World Radiation Center, Dorfstrasse 33, 7260 Davos Dorf, Switzerland
Ingo Kröger
Physikalisch-Technische Bundesanstalt, Bundesallee 100, Braunschweig, Germany
Luca Egli
Physikalisch-Meteorologisches Observatorium Davos, World Radiation Center, Dorfstrasse 33, 7260 Davos Dorf, Switzerland
Gregor Hülsen
Physikalisch-Meteorologisches Observatorium Davos, World Radiation Center, Dorfstrasse 33, 7260 Davos Dorf, Switzerland
Stefan Riechelmann
Physikalisch-Technische Bundesanstalt, Bundesallee 100, Braunschweig, Germany
Peter Sperfeld
Physikalisch-Technische Bundesanstalt, Bundesallee 100, Braunschweig, Germany
Related authors
Ilias Fountoulakis, Kyriaki Papachristopoulou, Stelios Kazadzis, Gregor Hülsen, Julian Gröbner, Ioannis-Panagiotis Raptis, Dimitra Kouklaki, Akriti Masoom, Charalampos Kontoes, and Christos S. Zerefos
EGUsphere, https://doi.org/10.5194/egusphere-2024-2964, https://doi.org/10.5194/egusphere-2024-2964, 2024
Short summary
Short summary
The UVIOS2 model has been evaluated at Davos, Switzerland during the UVCIII campaign. The accuracy in the modelled UV indices has been assessed for different combinations of model inputs. A good overall agreement between UVIOS2 and the world reference spectroradiometer QASUME was found (average ratio of ~1 between the modelled and measured UV index), although the variability in the ratio can be large under cloudy conditions.
Monica Campanelli, Victor Estellés, Gaurav Kumar, Teruyuki Nakajima, Masahiro Momoi, Julian Gröbner, Stelios Kazadzis, Natalia Kouremeti, Angelos Karanikolas, Africa Barreto, Saulius Nevas, Kerstin Schwind, Philipp Schneider, Iiro Harju, Petri Kärhä, Henri Diémoz, Rei Kudo, Akihiro Uchiyama, Akihiro Yamazaki, Anna Maria Iannarelli, Gabriele Mevi, Annalisa Di Bernardino, and Stefano Casadio
Atmos. Meas. Tech., 17, 5029–5050, https://doi.org/10.5194/amt-17-5029-2024, https://doi.org/10.5194/amt-17-5029-2024, 2024
Short summary
Short summary
To retrieve columnar aerosol properties from sun photometers, some calibration factors are needed. The on-site calibrations, performed as frequently as possible to monitor changes in the machine conditions, allow operators to track and evaluate the calibration status on a continuous basis, reducing the data gaps incurred by the periodic shipments for performing centralized calibrations. The performance of the on-site calibration procedures was evaluated, providing very good results.
Karl Voglmeier, Voltaire A. Velazco, Luca Egli, Julian Gröbner, Alberto Redondas, and Wolfgang Steinbrecht
Atmos. Meas. Tech., 17, 2277–2294, https://doi.org/10.5194/amt-17-2277-2024, https://doi.org/10.5194/amt-17-2277-2024, 2024
Short summary
Short summary
Comparison between total ozone column (TOC) measurements from ground-based Dobson and Brewer spectrophotometers generally reveals seasonally varying differences of a few percent. This study recommends a new TOC retrieval approach, which effectively eliminates these seasonally varying differences by applying new ozone absorption cross sections, appropriate slit functions for the Dobson instrument, and climatological values for the effective ozone temperature.
Antonio Fernando Almansa, África Barreto, Natalia Kouremeti, Ramiro González, Akriti Masoom, Carlos Toledano, Julian Gröbner, Rosa Delia García, Yenny González, Stelios Kazadzis, Stéphane Victori, Óscar Álvarez, Fabrice Maupin, Virgilio Carreño, Victoria Eugenia Cachorro, and Emilio Cuevas
Atmos. Meas. Tech., 17, 659–675, https://doi.org/10.5194/amt-17-659-2024, https://doi.org/10.5194/amt-17-659-2024, 2024
Short summary
Short summary
This paper applies sun photometer synergies to improve calibration transference between different sun photometers and also enhance their quality assurance and quality control. We have validated this technique using different instrumentation, the WMO-GAW and NASA-AERONET references, under different aerosol regimes using the standard Langley calibration method as a reference.
Óscar Alvárez, África Barreto, Omaira E. García, Frank Hase, Rosa D. García, Julian Gröbner, Sergio F. León-Luis, Eliezer Sepúlveda, Virgilio Carreño, Antonio Alcántara, Ramón Ramos, A. Fernando Almansa, Stelios Kazadzis, Noémie Taquet, Carlos Toledano, and Emilio Cuevas
Atmos. Meas. Tech., 16, 4861–4884, https://doi.org/10.5194/amt-16-4861-2023, https://doi.org/10.5194/amt-16-4861-2023, 2023
Short summary
Short summary
In this work, we have extended the capabilities of a portable Fourier transform infrared (FTIR) instrument, which was originally designed to provide high-quality greenhouse gas monitoring within COCCON (COllaborative Carbon Column Observing Network). The extension allows the spectrometer to now also provide coincidentally column-integrated aerosol information. This addition of a reference instrument to a global network will be utilised to enhance our understanding of atmospheric chemistry.
Verena Schenzinger, Axel Kreuter, Barbara Klotz, Michael Schwarzmann, and Julian Gröbner
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2023-188, https://doi.org/10.5194/amt-2023-188, 2023
Revised manuscript not accepted
Short summary
Short summary
We present a fast an easy method to incorporate clouds from satellite imagery into a model for calculating surface UV index maps in near-real time. To judge the quality of the model, we compare our results to measurements from ground based detectors. We discuss in detail where variations in either of the values come from and why satellite and ground values might not necessarily be comparable in every situation.
Julian Gröbner, Natalia Kouremeti, Gregor Hülsen, Ralf Zuber, Mario Ribnitzky, Saulius Nevas, Peter Sperfeld, Kerstin Schwind, Philipp Schneider, Stelios Kazadzis, África Barreto, Tom Gardiner, Kavitha Mottungan, David Medland, and Marc Coleman
Atmos. Meas. Tech., 16, 4667–4680, https://doi.org/10.5194/amt-16-4667-2023, https://doi.org/10.5194/amt-16-4667-2023, 2023
Short summary
Short summary
Spectral solar irradiance measurements traceable to the International System of Units (SI) allow for intercomparability between instruments and for their validation according to metrological standards. Here we also validate and reduce the uncertainties of the top-of-atmosphere TSIS-1 Hybrid Solar Reference Spectrum (HSRS). The management of large networks, e.g. AERONET or GAW-PFR, will benefit from reducing logistical overhead, improving their resilience and achieving metrological traceability.
Luca Egli, Julian Gröbner, Herbert Schill, and Eliane Maillard Barras
Atmos. Meas. Tech., 16, 2889–2902, https://doi.org/10.5194/amt-16-2889-2023, https://doi.org/10.5194/amt-16-2889-2023, 2023
Short summary
Short summary
This paper introduces a new method to retrieve total column ozone with spectral ground-based measurements from a novel array spectroradiometer. Total column ozone estimates using the small, cost-effective, and robust instrument and the new retrieval method are compared with other co-located total column ozone instruments. The comparison shows that the new system performs similarly to other well-established instruments, which require substantially more maintenance than the system introduced here.
Xiaoyi Zhao, Vitali Fioletov, Alberto Redondas, Julian Gröbner, Luca Egli, Franz Zeilinger, Javier López-Solano, Alberto Berjón Arroyo, James Kerr, Eliane Maillard Barras, Herman Smit, Michael Brohart, Reno Sit, Akira Ogyu, Ihab Abboud, and Sum Chi Lee
Atmos. Meas. Tech., 16, 2273–2295, https://doi.org/10.5194/amt-16-2273-2023, https://doi.org/10.5194/amt-16-2273-2023, 2023
Short summary
Short summary
The Brewer ozone spectrophotometer is one of the World Meteorological Organization (WMO) Global Atmosphere Watch (GAW)'s standard ozone monitoring instruments since the 1980s. This work is aimed at obtaining answers to (1) why Brewer primary calibration work can only be performed at certain sites (e.g., Izaña and MLO) and (2) what is needed to assure the equivalence of calibration quality from different sites.
Bruce W. Forgan, Julian Gröbner, and Ibrahim Reda
Atmos. Meas. Tech., 16, 727–743, https://doi.org/10.5194/amt-16-727-2023, https://doi.org/10.5194/amt-16-727-2023, 2023
Short summary
Short summary
This paper investigates the Absolute Cavity Pyrgeometer (ACP) and its use in measuring atmospheric terrestrial irradiances traceable to the standard system of units (SI). This work fits into the objective of the Expert Team on Radiation References, established by the World Meteorological Organization (WMO), to develop and validate instrumentation that can be used as reference instruments for terrestrial radiation measurements.
Angelos Karanikolas, Natalia Kouremeti, Julian Gröbner, Luca Egli, and Stelios Kazadzis
Atmos. Meas. Tech., 15, 5667–5680, https://doi.org/10.5194/amt-15-5667-2022, https://doi.org/10.5194/amt-15-5667-2022, 2022
Short summary
Short summary
The aim of this work is to investigate the limitations of calculating long-term trends of a parameter that quantifies the overall effect of atmospheric aerosols on the solar radiation. A main finding is that even instruments with good agreement between their observations can show significantly different linear trends. By calculating time-varying trends, the trend agreement is shown to improve. We also show that different methods of trend estimation can result in significant trend differences.
Luca Egli, Julian Gröbner, Gregor Hülsen, Herbert Schill, and René Stübi
Atmos. Meas. Tech., 15, 1917–1930, https://doi.org/10.5194/amt-15-1917-2022, https://doi.org/10.5194/amt-15-1917-2022, 2022
Short summary
Short summary
This study presents traceable total column ozone retrievals from direct solar spectral irradiance measurements. The retrieved ozone does not require any field calibration with a reference instrument as it is required for other operational network instruments such as Brewer or Dobson. Total column ozone can be retrieved with a traceable overall standard uncertainty of less than 0.8 % indicating a benchmark uncertainty for total column ozone measurements.
Panagiotis G. Kosmopoulos, Stelios Kazadzis, Alois W. Schmalwieser, Panagiotis I. Raptis, Kyriakoula Papachristopoulou, Ilias Fountoulakis, Akriti Masoom, Alkiviadis F. Bais, Julia Bilbao, Mario Blumthaler, Axel Kreuter, Anna Maria Siani, Kostas Eleftheratos, Chrysanthi Topaloglou, Julian Gröbner, Bjørn Johnsen, Tove M. Svendby, Jose Manuel Vilaplana, Lionel Doppler, Ann R. Webb, Marina Khazova, Hugo De Backer, Anu Heikkilä, Kaisa Lakkala, Janusz Jaroslawski, Charikleia Meleti, Henri Diémoz, Gregor Hülsen, Barbara Klotz, John Rimmer, and Charalampos Kontoes
Atmos. Meas. Tech., 14, 5657–5699, https://doi.org/10.5194/amt-14-5657-2021, https://doi.org/10.5194/amt-14-5657-2021, 2021
Short summary
Short summary
Large-scale retrievals of the ultraviolet index (UVI) in real time by exploiting the modern Earth observation data and techniques are capable of forming operational early warning systems that raise awareness among citizens of the health implications of high UVI doses. In this direction a novel UVI operating system, the so-called UVIOS, was introduced for massive outputs, while its performance was tested against ground-based measurements revealing a dependence on the input quality and resolution.
Ralf Zuber, Ulf Köhler, Luca Egli, Mario Ribnitzky, Wolfgang Steinbrecht, and Julian Gröbner
Atmos. Meas. Tech., 14, 4915–4928, https://doi.org/10.5194/amt-14-4915-2021, https://doi.org/10.5194/amt-14-4915-2021, 2021
Short summary
Short summary
We validated two BTS-based systems in a longer-term TOC analysis in the 2019/2020 campaign at Hohenpeißenberg and Davos. The results showed a deviation of the BTS-Solar to Brewers of < 0.1 % with a k = 2 of < 1.5 %. Koherent showed a deviation of 1.7 % with a k = 2 of 2.7 %. Resultingly, the BTS-Solar performance is comparable to Brewers in Hohenpeißenberg. Koherent shows a seasonal variation in Davos due to the sensitivity of its TOC retrieval algorithm to stratospheric temperature.
Marek Šmíd, Geiland Porrovecchio, Jiří Tesař, Tim Burnitt, Luca Egli, Julian Grőbner, Petr Linduška, and Martin Staněk
Atmos. Meas. Tech., 14, 3573–3582, https://doi.org/10.5194/amt-14-3573-2021, https://doi.org/10.5194/amt-14-3573-2021, 2021
Short summary
Short summary
We designed and developed a tuneable and portable radiation source (TuPS) to provide a reference wavelength scale, with a bandwidth of emitted radiation of 0.13 nm and uncertainty in wavelength of 0.02 nm. TuPS was successfully used for the in-field characterization of 14 Dobson spectrophotometers in campaigns in Europe. The line spread functions of Dobsons measured by TuPS in conjunction with the cross-sections from IUP improves the consistency between the Dobson and Brewer from 3 % to 1 %.
Julian Gröbner, Herbert Schill, Luca Egli, and René Stübi
Atmos. Meas. Tech., 14, 3319–3331, https://doi.org/10.5194/amt-14-3319-2021, https://doi.org/10.5194/amt-14-3319-2021, 2021
Short summary
Short summary
The world's longest continuous total column ozone time series was initiated in 1926 at the Lichtklimatisches Observatorium (LKO), at Arosa, in the Swiss Alps. The measurements between Dobson and Brewer spectroradiometers have shown seasonal variations of the order of 2 %. The results of the study show that the consistency between the two instrument types can be significantly improved when the ozone cross-sections from Serdyuchenko et al. (2013) and the measured slit functions are used.
Kaisa Lakkala, Jukka Kujanpää, Colette Brogniez, Nicolas Henriot, Antti Arola, Margit Aun, Frédérique Auriol, Alkiviadis F. Bais, Germar Bernhard, Veerle De Bock, Maxime Catalfamo, Christine Deroo, Henri Diémoz, Luca Egli, Jean-Baptiste Forestier, Ilias Fountoulakis, Katerina Garane, Rosa Delia Garcia, Julian Gröbner, Seppo Hassinen, Anu Heikkilä, Stuart Henderson, Gregor Hülsen, Bjørn Johnsen, Niilo Kalakoski, Angelos Karanikolas, Tomi Karppinen, Kevin Lamy, Sergio F. León-Luis, Anders V. Lindfors, Jean-Marc Metzger, Fanny Minvielle, Harel B. Muskatel, Thierry Portafaix, Alberto Redondas, Ricardo Sanchez, Anna Maria Siani, Tove Svendby, and Johanna Tamminen
Atmos. Meas. Tech., 13, 6999–7024, https://doi.org/10.5194/amt-13-6999-2020, https://doi.org/10.5194/amt-13-6999-2020, 2020
Short summary
Short summary
The TROPOspheric Monitoring Instrument (TROPOMI) onboard the Sentinel-5 Precursor (S5P) satellite was launched on 13 October 2017 to provide the atmospheric composition for atmosphere and climate research. Ground-based data from 25 sites located in Arctic, subarctic, temperate, equatorial and Antarctic
areas were used for the validation of the TROPOMI surface ultraviolet (UV) radiation product. For most sites 60 %–80 % of TROPOMI data was within ± 20 % of ground-based data.
Ilias Fountoulakis, Henri Diémoz, Anna Maria Siani, Gregor Hülsen, and Julian Gröbner
Earth Syst. Sci. Data, 12, 2787–2810, https://doi.org/10.5194/essd-12-2787-2020, https://doi.org/10.5194/essd-12-2787-2020, 2020
Short summary
Short summary
In this study we discuss the procedures and the technical aspects which ensure the high quality of the measurements of the global solar ultraviolet (UV) irradiance performed by a Bentham spectroradiometer located at Aosta–Saint-Christophe (north-western Alps), Italy. This particular instrument is the reference for the Aosta Valley UV monitoring network, which is the first UV monitoring network in Italy. The final spectra constitute one of the most accurate datasets globally.
Christine Aebi, Julian Gröbner, Stelios Kazadzis, Laurent Vuilleumier, Antonis Gkikas, and Niklaus Kämpfer
Atmos. Meas. Tech., 13, 907–923, https://doi.org/10.5194/amt-13-907-2020, https://doi.org/10.5194/amt-13-907-2020, 2020
Short summary
Short summary
Clouds are one of the largest sources of uncertainties in climate models. The current study estimates the cloud optical thickness (COT), the effective droplet radius and the single scattering albedo of stratus–altostratus and cirrus–cirrostratus clouds in Payerne, Switzerland, by combining ground- and satellite-based measurements and radiative transfer models. The estimated values are thereafter compared with data retrieved from other methods. The mean COT is distinct for different seasons.
Stephan Nyeki, Stefan Wacker, Christine Aebi, Julian Gröbner, Giovanni Martucci, and Laurent Vuilleumier
Atmos. Chem. Phys., 19, 13227–13241, https://doi.org/10.5194/acp-19-13227-2019, https://doi.org/10.5194/acp-19-13227-2019, 2019
Short summary
Short summary
The trends of meteorological parameters and surface downward shortwave radiation (DSR) and downward longwave radiation (DLR) were analysed at four stations (between 370 and 3580 m a. s. l.) in Switzerland for the 1996–2015 period. Trends in DSR and DLR were positive during cloudy as well as clear conditions. The trend due to the influence of clouds decreased in magnitude, which implies a reduction in cloud cover and/or a change towards a different cloud type over the four Swiss sites.
Emilio Cuevas, Pedro Miguel Romero-Campos, Natalia Kouremeti, Stelios Kazadzis, Petri Räisänen, Rosa Delia García, Africa Barreto, Carmen Guirado-Fuentes, Ramón Ramos, Carlos Toledano, Fernando Almansa, and Julian Gröbner
Atmos. Meas. Tech., 12, 4309–4337, https://doi.org/10.5194/amt-12-4309-2019, https://doi.org/10.5194/amt-12-4309-2019, 2019
Short summary
Short summary
A comprehensive comparison of more than 70 000 synchronous 1 min aerosol optical depth (AOD) data from 3 Global Atmosphere Watch precision filter radiometers (GAW-PFR) and 15 Aerosol Robotic Network Cimel radiometers (AERONET-Cimel) was performed for the four
nearwavelengths (380, 440, 500 and 870 nm) in the period 2005–2015. The goal of this study is to assess whether their long term AOD data are comparable and consistent.
Christine Aebi, Julian Gröbner, and Niklaus Kämpfer
Atmos. Meas. Tech., 11, 5549–5563, https://doi.org/10.5194/amt-11-5549-2018, https://doi.org/10.5194/amt-11-5549-2018, 2018
Short summary
Short summary
A newly developed hemispherical thermal infrared cloud camera (IRCCAM) is presented. The IRCCAM allows automatic cloud detection during the day and at night-time. The cloud fraction determined from the IRCCAM is compared with the cloud fraction determined from other instruments over a time period of 2 years. The IRCCAM has an agreement of +/- 2 oktas cloud fraction in 90 % of the data compared to other instruments. There are no significant differences between seasons or different times of day.
Carlos Toledano, Ramiro González, David Fuertes, Emilio Cuevas, Thomas F. Eck, Stelios Kazadzis, Natalia Kouremeti, Julian Gröbner, Philippe Goloub, Luc Blarel, Roberto Román, África Barreto, Alberto Berjón, Brent N. Holben, and Victoria E. Cachorro
Atmos. Chem. Phys., 18, 14555–14567, https://doi.org/10.5194/acp-18-14555-2018, https://doi.org/10.5194/acp-18-14555-2018, 2018
Short summary
Short summary
Most of the ground-based radiometric networks have their reference instruments and/or calibrate them at Mauna Loa or Izaña. The suitability of these high-mountain stations for absolute radiometric calibrations is investigated with the support of 20 years of first-class Sun photometer data from the AERONET and GAW-PFR networks. We analyze the number of calibration days at each site in a climatological sense and investigate the uncertainty of the calibrations based on long-term statistics.
Kaisa Lakkala, Antti Arola, Julian Gröbner, Sergio Fabian León-Luis, Alberto Redondas, Stelios Kazadzis, Tomi Karppinen, Juha Matti Karhu, Luca Egli, Anu Heikkilä, Tapani Koskela, Antonio Serrano, and José Manuel Vilaplana
Atmos. Meas. Tech., 11, 5167–5180, https://doi.org/10.5194/amt-11-5167-2018, https://doi.org/10.5194/amt-11-5167-2018, 2018
Short summary
Short summary
The performance of the cosine error correction method for correcting spectral UV measurements of the Brewer spectroradiometer was studied. The correction depends on the sky radiation distribution, which can change during one spectral scan. The results showed that the correction varied between 4 and 14 %, and that the relative differences between the reference and the Brewer diminished by 10 %. The method is applicable to other instruments as long as the required input parameters are available.
Alberto Redondas, Virgilio Carreño, Sergio F. León-Luis, Bentorey Hernández-Cruz, Javier López-Solano, Juan J. Rodriguez-Franco, José M. Vilaplana, Julian Gröbner, John Rimmer, Alkiviadis F. Bais, Vladimir Savastiouk, Juan R. Moreta, Lamine Boulkelia, Nis Jepsen, Keith M. Wilson, Vadim Shirotov, and Tomi Karppinen
Atmos. Chem. Phys., 18, 9441–9455, https://doi.org/10.5194/acp-18-9441-2018, https://doi.org/10.5194/acp-18-9441-2018, 2018
Short summary
Short summary
This work shows an overview of the total ozone comparison of the Brewer instrument during the 10th RBCC-E campaign in a joint effort with the EUBREWNET COST 1207 action. The status of the network after 2 years of calibration shows 16 out of the 21 participating Brewer instruments (76 %) agreed within better than ±1 %, and 10 instruments (50 %) agreed within better than ±0.5 %. After applying the final calibration and the stray light correction all working instruments agreed at the ±0.5 % level.
Anna Vaskuri, Petri Kärhä, Luca Egli, Julian Gröbner, and Erkki Ikonen
Atmos. Meas. Tech., 11, 3595–3610, https://doi.org/10.5194/amt-11-3595-2018, https://doi.org/10.5194/amt-11-3595-2018, 2018
Short summary
Short summary
In this work, we introduce a Monte Carlo uncertainty analysis that takes into account possible systematic spectral deviations in the atmospheric full spectrum ozone retrieval method. Accounting for possible systematic spectral deviations in the spectral data is important since they produce larger total ozone column uncertainties than uncorrelated noise-like variations that traditional uncertainty estimations predict.
Rosa Delia García, Africa Barreto, Emilio Cuevas, Julian Gröbner, Omaira Elena García, Angel Gómez-Peláez, Pedro Miguel Romero-Campos, Alberto Redondas, Victoria Eugenia Cachorro, and Ramon Ramos
Geosci. Model Dev., 11, 2139–2152, https://doi.org/10.5194/gmd-11-2139-2018, https://doi.org/10.5194/gmd-11-2139-2018, 2018
Short summary
Short summary
A 7-year comparison study between measured and simulated longwave
downward radiation under cloud-free conditions has been performed at BSRN Izaña. Results show an excellent agreement with a mean bias (simulated–measured) less than 1.1 % and RMSE less than 1 %, which are within the instrumental error (2 %).
Daniela Meloni, Alcide di Sarra, Gérard Brogniez, Cyrielle Denjean, Lorenzo De Silvestri, Tatiana Di Iorio, Paola Formenti, José L. Gómez-Amo, Julian Gröbner, Natalia Kouremeti, Giuliano Liuzzi, Marc Mallet, Giandomenico Pace, and Damiano M. Sferlazzo
Atmos. Chem. Phys., 18, 4377–4401, https://doi.org/10.5194/acp-18-4377-2018, https://doi.org/10.5194/acp-18-4377-2018, 2018
Short summary
Short summary
This study examines how different aerosol optical properties determine the dust longwave radiative effects at the surface, in the atmosphere and at the top of the atmosphere, based on the combination of remote sensing and in situ observations from the ground, from airborne sensors, and from space, by means of radiative transfer modelling. The closure experiment is based on longwave irradiances and spectral brightness temperatures measured during the 2013 ChArMEx–ADRIMED campaign at Lampedusa.
Christof Janssen, Hadj Elandaloussi, and Julian Gröbner
Atmos. Meas. Tech., 11, 1707–1723, https://doi.org/10.5194/amt-11-1707-2018, https://doi.org/10.5194/amt-11-1707-2018, 2018
Short summary
Short summary
Monitoring ozone layer recovery at a rate of few percent per decade requires dedicated instrumentation and spectroscopic data of the highest quality. Highly accurate absorption cross sections of ozone are rare, especially in the important UV region between 300 and 340 nm. Our measurement provides the first reference point with permil level of accuracy in this range. Interestingly, our value is lower than currently used data. This might resolve an inconsistency between UV and IR measurements.
Javier López-Solano, Alberto Redondas, Thomas Carlund, Juan J. Rodriguez-Franco, Henri Diémoz, Sergio F. León-Luis, Bentorey Hernández-Cruz, Carmen Guirado-Fuentes, Natalia Kouremeti, Julian Gröbner, Stelios Kazadzis, Virgilio Carreño, Alberto Berjón, Daniel Santana-Díaz, Manuel Rodríguez-Valido, Veerle De Bock, Juan R. Moreta, John Rimmer, Andrew R. D. Smedley, Lamine Boulkelia, Nis Jepsen, Paul Eriksen, Alkiviadis F. Bais, Vadim Shirotov, José M. Vilaplana, Keith M. Wilson, and Tomi Karppinen
Atmos. Chem. Phys., 18, 3885–3902, https://doi.org/10.5194/acp-18-3885-2018, https://doi.org/10.5194/acp-18-3885-2018, 2018
Short summary
Short summary
The European Brewer Network (EUBREWNET, COST Action ES1207) is comprised of close to 50 instruments and currently provides near-real-time ozone and UV data. Aerosols also play key role in the Earth–atmosphere system and introduce a large uncertainty into our understanding of climate change. In this work we describe and validate a method to incorporate the measurement of aerosols in EUBREWNET. We find that this Brewer network can provide reliable aerosol data across Europe in the UV range.
Stelios Kazadzis, Natalia Kouremeti, Henri Diémoz, Julian Gröbner, Bruce W. Forgan, Monica Campanelli, Victor Estellés, Kathleen Lantz, Joseph Michalsky, Thomas Carlund, Emilio Cuevas, Carlos Toledano, Ralf Becker, Stephan Nyeki, Panagiotis G. Kosmopoulos, Viktar Tatsiankou, Laurent Vuilleumier, Frederick M. Denn, Nozomu Ohkawara, Osamu Ijima, Philippe Goloub, Panagiotis I. Raptis, Michael Milner, Klaus Behrens, Africa Barreto, Giovanni Martucci, Emiel Hall, James Wendell, Bryan E. Fabbri, and Christoph Wehrli
Atmos. Chem. Phys., 18, 3185–3201, https://doi.org/10.5194/acp-18-3185-2018, https://doi.org/10.5194/acp-18-3185-2018, 2018
Short summary
Short summary
Aerosol optical depth measured from ground-based sun photometers is the most important parameter for studying the changes in the Earth's radiation balance due to aerosols. Representatives for various sun photometer types belonging to individual institutions or international aerosol networks gather every 5 years, for 3 weeks, in Davos, Switzerland, in order to compare their aeorosol optical depth retrievals. This work presents the results of the latest (fourth) filter radiometer intercomparison.
Panagiotis-Ioannis Raptis, Stelios Kazadzis, Julian Gröbner, Natalia Kouremeti, Lionel Doppler, Ralf Becker, and Constantinos Helmis
Atmos. Meas. Tech., 11, 1143–1157, https://doi.org/10.5194/amt-11-1143-2018, https://doi.org/10.5194/amt-11-1143-2018, 2018
Short summary
Short summary
The purpose of this work is to retrieve integrated water vapour using spectral measurements from Precision Solar Spectroradiometer (PSR). Two different approaches were developed one using single-channel direct sun irradiance measurements, and the second one integrating at a certain spectral region. The results of the spectral approach are closer to the retrievals of non-photometric techniques (GPS, microwave radiometer and radiosondes), suggesting this method provide more accurate IWV product.
Stelios Kazadzis, Natalia Kouremeti, Stephan Nyeki, Julian Gröbner, and Christoph Wehrli
Geosci. Instrum. Method. Data Syst., 7, 39–53, https://doi.org/10.5194/gi-7-39-2018, https://doi.org/10.5194/gi-7-39-2018, 2018
Short summary
Short summary
The World Optical Depth Research Calibration Center (WORCC) has been established after the recommendations of WMO for calibration of aerosol optical depth (AOD) -related sun photometers. WORCC is mandated to initiate homogenization activities among different AOD networks and to run a network (GAW-PFR) of sun photometers. To calibrate such instruments aiming at low measurement uncertainties the quality assurance, quality control and a basic hierarchy have to be defined and followed.
Christine Aebi, Julian Gröbner, Niklaus Kämpfer, and Laurent Vuilleumier
Atmos. Meas. Tech., 10, 4587–4600, https://doi.org/10.5194/amt-10-4587-2017, https://doi.org/10.5194/amt-10-4587-2017, 2017
Short summary
Short summary
The current study analyses the cloud radiative effect during the daytime depending on cloud fraction and cloud type at two stations in Switzerland over a time period of 3–5 years. Information about fractional cloud coverage and cloud type is retrieved from images taken by visible all-sky cameras. Cloud cover, cloud type and other atmospheric parameters have an influence on the magnitude of the longwave cloud effect as well as on the shortwave.
René Stübi, Herbert Schill, Jörg Klausen, Laurent Vuilleumier, Julian Gröbner, Luca Egli, and Dominique Ruffieux
Atmos. Meas. Tech., 10, 4479–4490, https://doi.org/10.5194/amt-10-4479-2017, https://doi.org/10.5194/amt-10-4479-2017, 2017
Short summary
Short summary
Long-term measurement series are the pillars of all climate change analysis. The Arosa total ozone series is the world's longest record, starting in 1926. To secure the future of these measurements, it is foreseen to move the instruments in Davos. To ascertain that the series will not be affected by this change, a multiyear campaign of parallel measurements on both sites has been done. The analysis of these data is presented and it is concluded that no discernible difference can be identified.
Stephan Nyeki, Stefan Wacker, Julian Gröbner, Wolfgang Finsterle, and Martin Wild
Atmos. Meas. Tech., 10, 3057–3071, https://doi.org/10.5194/amt-10-3057-2017, https://doi.org/10.5194/amt-10-3057-2017, 2017
Short summary
Short summary
A large number of radiometers used to measure solar and terrestrial broadband radiation are traceable to World Standard Groups at PMOD/WRC in Davos, Switzerland. A small correction of each group may be required in the future, and this study examines the methods and implications of this on data sets collected at four remote baseline stations since the 1990s. The goal is to develop a better estimate of the solar and terrestrial radiation budget at the Earth's surface.
Thomas Carlund, Natalia Kouremeti, Stelios Kazadzis, and Julian Gröbner
Atmos. Meas. Tech., 10, 905–923, https://doi.org/10.5194/amt-10-905-2017, https://doi.org/10.5194/amt-10-905-2017, 2017
Short summary
Short summary
Aerosols play an important role in atmospheric processes. Aerosol optical depth is the most common measure of columnar aerosol load. We present a sunphotometer called UVPFR that is able to measure aerosol optical depth in the ultraviolet range, including the calibration, characterization and validation of the instrument/measurements. The instrument will serve as a reference on the intercalibration of Brewer spectrophotometers that are also able to measure aerosol optical depth in the UV region.
Christos S. Zerefos, Kostas Eleftheratos, John Kapsomenakis, Stavros Solomos, Antje Inness, Dimitris Balis, Alberto Redondas, Henk Eskes, Marc Allaart, Vassilis Amiridis, Arne Dahlback, Veerle De Bock, Henri Diémoz, Ronny Engelmann, Paul Eriksen, Vitali Fioletov, Julian Gröbner, Anu Heikkilä, Irina Petropavlovskikh, Janusz Jarosławski, Weine Josefsson, Tomi Karppinen, Ulf Köhler, Charoula Meleti, Christos Repapis, John Rimmer, Vladimir Savinykh, Vadim Shirotov, Anna Maria Siani, Andrew R. D. Smedley, Martin Stanek, and René Stübi
Atmos. Chem. Phys., 17, 551–574, https://doi.org/10.5194/acp-17-551-2017, https://doi.org/10.5194/acp-17-551-2017, 2017
Short summary
Short summary
The paper makes a convincing case that the Brewer network is capable of detecting enhanced SO2 columns, as observed, e.g., after volcanic eruptions. For this reason, large volcanic eruptions of the past decade have been used to detect and forecast SO2 plumes of volcanic origin using the Brewer and other ground-based networks, aided by satellite, trajectory analysis calculations and modelling.
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
Short summary
Short summary
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.
África Barreto, Emilio Cuevas, María-José Granados-Muñoz, Lucas Alados-Arboledas, Pedro M. Romero, Julian Gröbner, Natalia Kouremeti, Antonio F. Almansa, Tom Stone, Carlos Toledano, Roberto Román, Mikhail Sorokin, Brent Holben, Marius Canini, and Margarita Yela
Atmos. Meas. Tech., 9, 631–654, https://doi.org/10.5194/amt-9-631-2016, https://doi.org/10.5194/amt-9-631-2016, 2016
Short summary
Short summary
This paper presents the new photometer CE318-T, able to perform daytime and
night-time photometric measurements using the sun and the moon as light
sources. This new device permits a complete cycle of diurnal aerosol and water vapour measurements to be extracted, valuable to enhance atmospheric monitoring. We have also highlighted the ability of this new device to capture short-term atmospheric variations, critical for climate studies.
M. Lothon, F. Lohou, D. Pino, F. Couvreux, E. R. Pardyjak, J. Reuder, J. Vilà-Guerau de Arellano, P Durand, O. Hartogensis, D. Legain, P. Augustin, B. Gioli, D. H. Lenschow, I. Faloona, C. Yagüe, D. C. Alexander, W. M. Angevine, E Bargain, J. Barrié, E. Bazile, Y. Bezombes, E. Blay-Carreras, A. van de Boer, J. L. Boichard, A. Bourdon, A. Butet, B. Campistron, O. de Coster, J. Cuxart, A. Dabas, C. Darbieu, K. Deboudt, H. Delbarre, S. Derrien, P. Flament, M. Fourmentin, A. Garai, F. Gibert, A. Graf, J. Groebner, F. Guichard, M. A. Jiménez, M. Jonassen, A. van den Kroonenberg, V. Magliulo, S. Martin, D. Martinez, L. Mastrorillo, A. F. Moene, F. Molinos, E. Moulin, H. P. Pietersen, B. Piguet, E. Pique, C. Román-Cascón, C. Rufin-Soler, F. Saïd, M. Sastre-Marugán, Y. Seity, G. J. Steeneveld, P. Toscano, O. Traullé, D. Tzanos, S. Wacker, N. Wildmann, and A. Zaldei
Atmos. Chem. Phys., 14, 10931–10960, https://doi.org/10.5194/acp-14-10931-2014, https://doi.org/10.5194/acp-14-10931-2014, 2014
S. Kazadzis, I. Veselovskii, V. Amiridis, J. Gröbner, A. Suvorina, S. Nyeki, E. Gerasopoulos, N. Kouremeti, M. Taylor, A. Tsekeri, and C. Wehrli
Atmos. Meas. Tech., 7, 2013–2025, https://doi.org/10.5194/amt-7-2013-2014, https://doi.org/10.5194/amt-7-2013-2014, 2014
A. Stenke, C. R. Hoyle, B. Luo, E. Rozanov, J. Gröbner, L. Maag, S. Brönnimann, and T. Peter
Atmos. Chem. Phys., 13, 9713–9729, https://doi.org/10.5194/acp-13-9713-2013, https://doi.org/10.5194/acp-13-9713-2013, 2013
T. Egorova, E. Rozanov, J. Gröbner, M. Hauser, and W. Schmutz
Atmos. Chem. Phys., 13, 3811–3823, https://doi.org/10.5194/acp-13-3811-2013, https://doi.org/10.5194/acp-13-3811-2013, 2013
Ilias Fountoulakis, Kyriaki Papachristopoulou, Stelios Kazadzis, Gregor Hülsen, Julian Gröbner, Ioannis-Panagiotis Raptis, Dimitra Kouklaki, Akriti Masoom, Charalampos Kontoes, and Christos S. Zerefos
EGUsphere, https://doi.org/10.5194/egusphere-2024-2964, https://doi.org/10.5194/egusphere-2024-2964, 2024
Short summary
Short summary
The UVIOS2 model has been evaluated at Davos, Switzerland during the UVCIII campaign. The accuracy in the modelled UV indices has been assessed for different combinations of model inputs. A good overall agreement between UVIOS2 and the world reference spectroradiometer QASUME was found (average ratio of ~1 between the modelled and measured UV index), although the variability in the ratio can be large under cloudy conditions.
Monica Campanelli, Victor Estellés, Gaurav Kumar, Teruyuki Nakajima, Masahiro Momoi, Julian Gröbner, Stelios Kazadzis, Natalia Kouremeti, Angelos Karanikolas, Africa Barreto, Saulius Nevas, Kerstin Schwind, Philipp Schneider, Iiro Harju, Petri Kärhä, Henri Diémoz, Rei Kudo, Akihiro Uchiyama, Akihiro Yamazaki, Anna Maria Iannarelli, Gabriele Mevi, Annalisa Di Bernardino, and Stefano Casadio
Atmos. Meas. Tech., 17, 5029–5050, https://doi.org/10.5194/amt-17-5029-2024, https://doi.org/10.5194/amt-17-5029-2024, 2024
Short summary
Short summary
To retrieve columnar aerosol properties from sun photometers, some calibration factors are needed. The on-site calibrations, performed as frequently as possible to monitor changes in the machine conditions, allow operators to track and evaluate the calibration status on a continuous basis, reducing the data gaps incurred by the periodic shipments for performing centralized calibrations. The performance of the on-site calibration procedures was evaluated, providing very good results.
Karl Voglmeier, Voltaire A. Velazco, Luca Egli, Julian Gröbner, Alberto Redondas, and Wolfgang Steinbrecht
Atmos. Meas. Tech., 17, 2277–2294, https://doi.org/10.5194/amt-17-2277-2024, https://doi.org/10.5194/amt-17-2277-2024, 2024
Short summary
Short summary
Comparison between total ozone column (TOC) measurements from ground-based Dobson and Brewer spectrophotometers generally reveals seasonally varying differences of a few percent. This study recommends a new TOC retrieval approach, which effectively eliminates these seasonally varying differences by applying new ozone absorption cross sections, appropriate slit functions for the Dobson instrument, and climatological values for the effective ozone temperature.
Antonio Fernando Almansa, África Barreto, Natalia Kouremeti, Ramiro González, Akriti Masoom, Carlos Toledano, Julian Gröbner, Rosa Delia García, Yenny González, Stelios Kazadzis, Stéphane Victori, Óscar Álvarez, Fabrice Maupin, Virgilio Carreño, Victoria Eugenia Cachorro, and Emilio Cuevas
Atmos. Meas. Tech., 17, 659–675, https://doi.org/10.5194/amt-17-659-2024, https://doi.org/10.5194/amt-17-659-2024, 2024
Short summary
Short summary
This paper applies sun photometer synergies to improve calibration transference between different sun photometers and also enhance their quality assurance and quality control. We have validated this technique using different instrumentation, the WMO-GAW and NASA-AERONET references, under different aerosol regimes using the standard Langley calibration method as a reference.
Óscar Alvárez, África Barreto, Omaira E. García, Frank Hase, Rosa D. García, Julian Gröbner, Sergio F. León-Luis, Eliezer Sepúlveda, Virgilio Carreño, Antonio Alcántara, Ramón Ramos, A. Fernando Almansa, Stelios Kazadzis, Noémie Taquet, Carlos Toledano, and Emilio Cuevas
Atmos. Meas. Tech., 16, 4861–4884, https://doi.org/10.5194/amt-16-4861-2023, https://doi.org/10.5194/amt-16-4861-2023, 2023
Short summary
Short summary
In this work, we have extended the capabilities of a portable Fourier transform infrared (FTIR) instrument, which was originally designed to provide high-quality greenhouse gas monitoring within COCCON (COllaborative Carbon Column Observing Network). The extension allows the spectrometer to now also provide coincidentally column-integrated aerosol information. This addition of a reference instrument to a global network will be utilised to enhance our understanding of atmospheric chemistry.
Verena Schenzinger, Axel Kreuter, Barbara Klotz, Michael Schwarzmann, and Julian Gröbner
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2023-188, https://doi.org/10.5194/amt-2023-188, 2023
Revised manuscript not accepted
Short summary
Short summary
We present a fast an easy method to incorporate clouds from satellite imagery into a model for calculating surface UV index maps in near-real time. To judge the quality of the model, we compare our results to measurements from ground based detectors. We discuss in detail where variations in either of the values come from and why satellite and ground values might not necessarily be comparable in every situation.
Julian Gröbner, Natalia Kouremeti, Gregor Hülsen, Ralf Zuber, Mario Ribnitzky, Saulius Nevas, Peter Sperfeld, Kerstin Schwind, Philipp Schneider, Stelios Kazadzis, África Barreto, Tom Gardiner, Kavitha Mottungan, David Medland, and Marc Coleman
Atmos. Meas. Tech., 16, 4667–4680, https://doi.org/10.5194/amt-16-4667-2023, https://doi.org/10.5194/amt-16-4667-2023, 2023
Short summary
Short summary
Spectral solar irradiance measurements traceable to the International System of Units (SI) allow for intercomparability between instruments and for their validation according to metrological standards. Here we also validate and reduce the uncertainties of the top-of-atmosphere TSIS-1 Hybrid Solar Reference Spectrum (HSRS). The management of large networks, e.g. AERONET or GAW-PFR, will benefit from reducing logistical overhead, improving their resilience and achieving metrological traceability.
Luca Egli, Julian Gröbner, Herbert Schill, and Eliane Maillard Barras
Atmos. Meas. Tech., 16, 2889–2902, https://doi.org/10.5194/amt-16-2889-2023, https://doi.org/10.5194/amt-16-2889-2023, 2023
Short summary
Short summary
This paper introduces a new method to retrieve total column ozone with spectral ground-based measurements from a novel array spectroradiometer. Total column ozone estimates using the small, cost-effective, and robust instrument and the new retrieval method are compared with other co-located total column ozone instruments. The comparison shows that the new system performs similarly to other well-established instruments, which require substantially more maintenance than the system introduced here.
Xiaoyi Zhao, Vitali Fioletov, Alberto Redondas, Julian Gröbner, Luca Egli, Franz Zeilinger, Javier López-Solano, Alberto Berjón Arroyo, James Kerr, Eliane Maillard Barras, Herman Smit, Michael Brohart, Reno Sit, Akira Ogyu, Ihab Abboud, and Sum Chi Lee
Atmos. Meas. Tech., 16, 2273–2295, https://doi.org/10.5194/amt-16-2273-2023, https://doi.org/10.5194/amt-16-2273-2023, 2023
Short summary
Short summary
The Brewer ozone spectrophotometer is one of the World Meteorological Organization (WMO) Global Atmosphere Watch (GAW)'s standard ozone monitoring instruments since the 1980s. This work is aimed at obtaining answers to (1) why Brewer primary calibration work can only be performed at certain sites (e.g., Izaña and MLO) and (2) what is needed to assure the equivalence of calibration quality from different sites.
Bruce W. Forgan, Julian Gröbner, and Ibrahim Reda
Atmos. Meas. Tech., 16, 727–743, https://doi.org/10.5194/amt-16-727-2023, https://doi.org/10.5194/amt-16-727-2023, 2023
Short summary
Short summary
This paper investigates the Absolute Cavity Pyrgeometer (ACP) and its use in measuring atmospheric terrestrial irradiances traceable to the standard system of units (SI). This work fits into the objective of the Expert Team on Radiation References, established by the World Meteorological Organization (WMO), to develop and validate instrumentation that can be used as reference instruments for terrestrial radiation measurements.
Angelos Karanikolas, Natalia Kouremeti, Julian Gröbner, Luca Egli, and Stelios Kazadzis
Atmos. Meas. Tech., 15, 5667–5680, https://doi.org/10.5194/amt-15-5667-2022, https://doi.org/10.5194/amt-15-5667-2022, 2022
Short summary
Short summary
The aim of this work is to investigate the limitations of calculating long-term trends of a parameter that quantifies the overall effect of atmospheric aerosols on the solar radiation. A main finding is that even instruments with good agreement between their observations can show significantly different linear trends. By calculating time-varying trends, the trend agreement is shown to improve. We also show that different methods of trend estimation can result in significant trend differences.
Luca Egli, Julian Gröbner, Gregor Hülsen, Herbert Schill, and René Stübi
Atmos. Meas. Tech., 15, 1917–1930, https://doi.org/10.5194/amt-15-1917-2022, https://doi.org/10.5194/amt-15-1917-2022, 2022
Short summary
Short summary
This study presents traceable total column ozone retrievals from direct solar spectral irradiance measurements. The retrieved ozone does not require any field calibration with a reference instrument as it is required for other operational network instruments such as Brewer or Dobson. Total column ozone can be retrieved with a traceable overall standard uncertainty of less than 0.8 % indicating a benchmark uncertainty for total column ozone measurements.
Panagiotis G. Kosmopoulos, Stelios Kazadzis, Alois W. Schmalwieser, Panagiotis I. Raptis, Kyriakoula Papachristopoulou, Ilias Fountoulakis, Akriti Masoom, Alkiviadis F. Bais, Julia Bilbao, Mario Blumthaler, Axel Kreuter, Anna Maria Siani, Kostas Eleftheratos, Chrysanthi Topaloglou, Julian Gröbner, Bjørn Johnsen, Tove M. Svendby, Jose Manuel Vilaplana, Lionel Doppler, Ann R. Webb, Marina Khazova, Hugo De Backer, Anu Heikkilä, Kaisa Lakkala, Janusz Jaroslawski, Charikleia Meleti, Henri Diémoz, Gregor Hülsen, Barbara Klotz, John Rimmer, and Charalampos Kontoes
Atmos. Meas. Tech., 14, 5657–5699, https://doi.org/10.5194/amt-14-5657-2021, https://doi.org/10.5194/amt-14-5657-2021, 2021
Short summary
Short summary
Large-scale retrievals of the ultraviolet index (UVI) in real time by exploiting the modern Earth observation data and techniques are capable of forming operational early warning systems that raise awareness among citizens of the health implications of high UVI doses. In this direction a novel UVI operating system, the so-called UVIOS, was introduced for massive outputs, while its performance was tested against ground-based measurements revealing a dependence on the input quality and resolution.
Ralf Zuber, Ulf Köhler, Luca Egli, Mario Ribnitzky, Wolfgang Steinbrecht, and Julian Gröbner
Atmos. Meas. Tech., 14, 4915–4928, https://doi.org/10.5194/amt-14-4915-2021, https://doi.org/10.5194/amt-14-4915-2021, 2021
Short summary
Short summary
We validated two BTS-based systems in a longer-term TOC analysis in the 2019/2020 campaign at Hohenpeißenberg and Davos. The results showed a deviation of the BTS-Solar to Brewers of < 0.1 % with a k = 2 of < 1.5 %. Koherent showed a deviation of 1.7 % with a k = 2 of 2.7 %. Resultingly, the BTS-Solar performance is comparable to Brewers in Hohenpeißenberg. Koherent shows a seasonal variation in Davos due to the sensitivity of its TOC retrieval algorithm to stratospheric temperature.
Marek Šmíd, Geiland Porrovecchio, Jiří Tesař, Tim Burnitt, Luca Egli, Julian Grőbner, Petr Linduška, and Martin Staněk
Atmos. Meas. Tech., 14, 3573–3582, https://doi.org/10.5194/amt-14-3573-2021, https://doi.org/10.5194/amt-14-3573-2021, 2021
Short summary
Short summary
We designed and developed a tuneable and portable radiation source (TuPS) to provide a reference wavelength scale, with a bandwidth of emitted radiation of 0.13 nm and uncertainty in wavelength of 0.02 nm. TuPS was successfully used for the in-field characterization of 14 Dobson spectrophotometers in campaigns in Europe. The line spread functions of Dobsons measured by TuPS in conjunction with the cross-sections from IUP improves the consistency between the Dobson and Brewer from 3 % to 1 %.
Julian Gröbner, Herbert Schill, Luca Egli, and René Stübi
Atmos. Meas. Tech., 14, 3319–3331, https://doi.org/10.5194/amt-14-3319-2021, https://doi.org/10.5194/amt-14-3319-2021, 2021
Short summary
Short summary
The world's longest continuous total column ozone time series was initiated in 1926 at the Lichtklimatisches Observatorium (LKO), at Arosa, in the Swiss Alps. The measurements between Dobson and Brewer spectroradiometers have shown seasonal variations of the order of 2 %. The results of the study show that the consistency between the two instrument types can be significantly improved when the ozone cross-sections from Serdyuchenko et al. (2013) and the measured slit functions are used.
Kaisa Lakkala, Jukka Kujanpää, Colette Brogniez, Nicolas Henriot, Antti Arola, Margit Aun, Frédérique Auriol, Alkiviadis F. Bais, Germar Bernhard, Veerle De Bock, Maxime Catalfamo, Christine Deroo, Henri Diémoz, Luca Egli, Jean-Baptiste Forestier, Ilias Fountoulakis, Katerina Garane, Rosa Delia Garcia, Julian Gröbner, Seppo Hassinen, Anu Heikkilä, Stuart Henderson, Gregor Hülsen, Bjørn Johnsen, Niilo Kalakoski, Angelos Karanikolas, Tomi Karppinen, Kevin Lamy, Sergio F. León-Luis, Anders V. Lindfors, Jean-Marc Metzger, Fanny Minvielle, Harel B. Muskatel, Thierry Portafaix, Alberto Redondas, Ricardo Sanchez, Anna Maria Siani, Tove Svendby, and Johanna Tamminen
Atmos. Meas. Tech., 13, 6999–7024, https://doi.org/10.5194/amt-13-6999-2020, https://doi.org/10.5194/amt-13-6999-2020, 2020
Short summary
Short summary
The TROPOspheric Monitoring Instrument (TROPOMI) onboard the Sentinel-5 Precursor (S5P) satellite was launched on 13 October 2017 to provide the atmospheric composition for atmosphere and climate research. Ground-based data from 25 sites located in Arctic, subarctic, temperate, equatorial and Antarctic
areas were used for the validation of the TROPOMI surface ultraviolet (UV) radiation product. For most sites 60 %–80 % of TROPOMI data was within ± 20 % of ground-based data.
Ilias Fountoulakis, Henri Diémoz, Anna Maria Siani, Gregor Hülsen, and Julian Gröbner
Earth Syst. Sci. Data, 12, 2787–2810, https://doi.org/10.5194/essd-12-2787-2020, https://doi.org/10.5194/essd-12-2787-2020, 2020
Short summary
Short summary
In this study we discuss the procedures and the technical aspects which ensure the high quality of the measurements of the global solar ultraviolet (UV) irradiance performed by a Bentham spectroradiometer located at Aosta–Saint-Christophe (north-western Alps), Italy. This particular instrument is the reference for the Aosta Valley UV monitoring network, which is the first UV monitoring network in Italy. The final spectra constitute one of the most accurate datasets globally.
Kaisa Lakkala, Margit Aun, Ricardo Sanchez, Germar Bernhard, Eija Asmi, Outi Meinander, Fernando Nollas, Gregor Hülsen, Tomi Karppinen, Veijo Aaltonen, Antti Arola, and Gerrit de Leeuw
Earth Syst. Sci. Data, 12, 947–960, https://doi.org/10.5194/essd-12-947-2020, https://doi.org/10.5194/essd-12-947-2020, 2020
Short summary
Short summary
A GUV multi-filter radiometer was set up at Marambio, 64° S, 56° W, Antarctica, in 2017. The instrument continuously measures ultraviolet (UV) radiation, visible (VIS) radiation and photosynthetically active radiation (PAR). The measurements are designed for providing high-quality long-term time series that can be used to assess the impact of global climate change in the Antarctic region. The data from the last 5 d are plotted and updated daily.
Christine Aebi, Julian Gröbner, Stelios Kazadzis, Laurent Vuilleumier, Antonis Gkikas, and Niklaus Kämpfer
Atmos. Meas. Tech., 13, 907–923, https://doi.org/10.5194/amt-13-907-2020, https://doi.org/10.5194/amt-13-907-2020, 2020
Short summary
Short summary
Clouds are one of the largest sources of uncertainties in climate models. The current study estimates the cloud optical thickness (COT), the effective droplet radius and the single scattering albedo of stratus–altostratus and cirrus–cirrostratus clouds in Payerne, Switzerland, by combining ground- and satellite-based measurements and radiative transfer models. The estimated values are thereafter compared with data retrieved from other methods. The mean COT is distinct for different seasons.
Stephan Nyeki, Stefan Wacker, Christine Aebi, Julian Gröbner, Giovanni Martucci, and Laurent Vuilleumier
Atmos. Chem. Phys., 19, 13227–13241, https://doi.org/10.5194/acp-19-13227-2019, https://doi.org/10.5194/acp-19-13227-2019, 2019
Short summary
Short summary
The trends of meteorological parameters and surface downward shortwave radiation (DSR) and downward longwave radiation (DLR) were analysed at four stations (between 370 and 3580 m a. s. l.) in Switzerland for the 1996–2015 period. Trends in DSR and DLR were positive during cloudy as well as clear conditions. The trend due to the influence of clouds decreased in magnitude, which implies a reduction in cloud cover and/or a change towards a different cloud type over the four Swiss sites.
Emilio Cuevas, Pedro Miguel Romero-Campos, Natalia Kouremeti, Stelios Kazadzis, Petri Räisänen, Rosa Delia García, Africa Barreto, Carmen Guirado-Fuentes, Ramón Ramos, Carlos Toledano, Fernando Almansa, and Julian Gröbner
Atmos. Meas. Tech., 12, 4309–4337, https://doi.org/10.5194/amt-12-4309-2019, https://doi.org/10.5194/amt-12-4309-2019, 2019
Short summary
Short summary
A comprehensive comparison of more than 70 000 synchronous 1 min aerosol optical depth (AOD) data from 3 Global Atmosphere Watch precision filter radiometers (GAW-PFR) and 15 Aerosol Robotic Network Cimel radiometers (AERONET-Cimel) was performed for the four
nearwavelengths (380, 440, 500 and 870 nm) in the period 2005–2015. The goal of this study is to assess whether their long term AOD data are comparable and consistent.
Nuno Pereira, David Bolsée, Peter Sperfeld, Sven Pape, Dominique Sluse, and Gaël Cessateur
Atmos. Meas. Tech., 11, 6605–6615, https://doi.org/10.5194/amt-11-6605-2018, https://doi.org/10.5194/amt-11-6605-2018, 2018
Short summary
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.
Christine Aebi, Julian Gröbner, and Niklaus Kämpfer
Atmos. Meas. Tech., 11, 5549–5563, https://doi.org/10.5194/amt-11-5549-2018, https://doi.org/10.5194/amt-11-5549-2018, 2018
Short summary
Short summary
A newly developed hemispherical thermal infrared cloud camera (IRCCAM) is presented. The IRCCAM allows automatic cloud detection during the day and at night-time. The cloud fraction determined from the IRCCAM is compared with the cloud fraction determined from other instruments over a time period of 2 years. The IRCCAM has an agreement of +/- 2 oktas cloud fraction in 90 % of the data compared to other instruments. There are no significant differences between seasons or different times of day.
Carlos Toledano, Ramiro González, David Fuertes, Emilio Cuevas, Thomas F. Eck, Stelios Kazadzis, Natalia Kouremeti, Julian Gröbner, Philippe Goloub, Luc Blarel, Roberto Román, África Barreto, Alberto Berjón, Brent N. Holben, and Victoria E. Cachorro
Atmos. Chem. Phys., 18, 14555–14567, https://doi.org/10.5194/acp-18-14555-2018, https://doi.org/10.5194/acp-18-14555-2018, 2018
Short summary
Short summary
Most of the ground-based radiometric networks have their reference instruments and/or calibrate them at Mauna Loa or Izaña. The suitability of these high-mountain stations for absolute radiometric calibrations is investigated with the support of 20 years of first-class Sun photometer data from the AERONET and GAW-PFR networks. We analyze the number of calibration days at each site in a climatological sense and investigate the uncertainty of the calibrations based on long-term statistics.
Kaisa Lakkala, Antti Arola, Julian Gröbner, Sergio Fabian León-Luis, Alberto Redondas, Stelios Kazadzis, Tomi Karppinen, Juha Matti Karhu, Luca Egli, Anu Heikkilä, Tapani Koskela, Antonio Serrano, and José Manuel Vilaplana
Atmos. Meas. Tech., 11, 5167–5180, https://doi.org/10.5194/amt-11-5167-2018, https://doi.org/10.5194/amt-11-5167-2018, 2018
Short summary
Short summary
The performance of the cosine error correction method for correcting spectral UV measurements of the Brewer spectroradiometer was studied. The correction depends on the sky radiation distribution, which can change during one spectral scan. The results showed that the correction varied between 4 and 14 %, and that the relative differences between the reference and the Brewer diminished by 10 %. The method is applicable to other instruments as long as the required input parameters are available.
Alberto Redondas, Virgilio Carreño, Sergio F. León-Luis, Bentorey Hernández-Cruz, Javier López-Solano, Juan J. Rodriguez-Franco, José M. Vilaplana, Julian Gröbner, John Rimmer, Alkiviadis F. Bais, Vladimir Savastiouk, Juan R. Moreta, Lamine Boulkelia, Nis Jepsen, Keith M. Wilson, Vadim Shirotov, and Tomi Karppinen
Atmos. Chem. Phys., 18, 9441–9455, https://doi.org/10.5194/acp-18-9441-2018, https://doi.org/10.5194/acp-18-9441-2018, 2018
Short summary
Short summary
This work shows an overview of the total ozone comparison of the Brewer instrument during the 10th RBCC-E campaign in a joint effort with the EUBREWNET COST 1207 action. The status of the network after 2 years of calibration shows 16 out of the 21 participating Brewer instruments (76 %) agreed within better than ±1 %, and 10 instruments (50 %) agreed within better than ±0.5 %. After applying the final calibration and the stray light correction all working instruments agreed at the ±0.5 % level.
Anna Vaskuri, Petri Kärhä, Luca Egli, Julian Gröbner, and Erkki Ikonen
Atmos. Meas. Tech., 11, 3595–3610, https://doi.org/10.5194/amt-11-3595-2018, https://doi.org/10.5194/amt-11-3595-2018, 2018
Short summary
Short summary
In this work, we introduce a Monte Carlo uncertainty analysis that takes into account possible systematic spectral deviations in the atmospheric full spectrum ozone retrieval method. Accounting for possible systematic spectral deviations in the spectral data is important since they produce larger total ozone column uncertainties than uncorrelated noise-like variations that traditional uncertainty estimations predict.
Rosa Delia García, Africa Barreto, Emilio Cuevas, Julian Gröbner, Omaira Elena García, Angel Gómez-Peláez, Pedro Miguel Romero-Campos, Alberto Redondas, Victoria Eugenia Cachorro, and Ramon Ramos
Geosci. Model Dev., 11, 2139–2152, https://doi.org/10.5194/gmd-11-2139-2018, https://doi.org/10.5194/gmd-11-2139-2018, 2018
Short summary
Short summary
A 7-year comparison study between measured and simulated longwave
downward radiation under cloud-free conditions has been performed at BSRN Izaña. Results show an excellent agreement with a mean bias (simulated–measured) less than 1.1 % and RMSE less than 1 %, which are within the instrumental error (2 %).
Ralf Zuber, Peter Sperfeld, Stefan Riechelmann, Saulius Nevas, Meelis Sildoja, and Gunther Seckmeyer
Atmos. Meas. Tech., 11, 2477–2484, https://doi.org/10.5194/amt-11-2477-2018, https://doi.org/10.5194/amt-11-2477-2018, 2018
Short summary
Short summary
A compact array spectroradiometer technology that enables precise and robust measurements of UV spectral irradiance is presented. We show that this instrument can retrieve total ozone column (TOC) accurately. The internal stray light, which is often the limiting factor for measurements in the UV spectral range, is physically reduced so that no other stray-light reduction methods are needed.
During an international total ozone measurement intercomparison, the high quality was verified.
Daniela Meloni, Alcide di Sarra, Gérard Brogniez, Cyrielle Denjean, Lorenzo De Silvestri, Tatiana Di Iorio, Paola Formenti, José L. Gómez-Amo, Julian Gröbner, Natalia Kouremeti, Giuliano Liuzzi, Marc Mallet, Giandomenico Pace, and Damiano M. Sferlazzo
Atmos. Chem. Phys., 18, 4377–4401, https://doi.org/10.5194/acp-18-4377-2018, https://doi.org/10.5194/acp-18-4377-2018, 2018
Short summary
Short summary
This study examines how different aerosol optical properties determine the dust longwave radiative effects at the surface, in the atmosphere and at the top of the atmosphere, based on the combination of remote sensing and in situ observations from the ground, from airborne sensors, and from space, by means of radiative transfer modelling. The closure experiment is based on longwave irradiances and spectral brightness temperatures measured during the 2013 ChArMEx–ADRIMED campaign at Lampedusa.
Christof Janssen, Hadj Elandaloussi, and Julian Gröbner
Atmos. Meas. Tech., 11, 1707–1723, https://doi.org/10.5194/amt-11-1707-2018, https://doi.org/10.5194/amt-11-1707-2018, 2018
Short summary
Short summary
Monitoring ozone layer recovery at a rate of few percent per decade requires dedicated instrumentation and spectroscopic data of the highest quality. Highly accurate absorption cross sections of ozone are rare, especially in the important UV region between 300 and 340 nm. Our measurement provides the first reference point with permil level of accuracy in this range. Interestingly, our value is lower than currently used data. This might resolve an inconsistency between UV and IR measurements.
Javier López-Solano, Alberto Redondas, Thomas Carlund, Juan J. Rodriguez-Franco, Henri Diémoz, Sergio F. León-Luis, Bentorey Hernández-Cruz, Carmen Guirado-Fuentes, Natalia Kouremeti, Julian Gröbner, Stelios Kazadzis, Virgilio Carreño, Alberto Berjón, Daniel Santana-Díaz, Manuel Rodríguez-Valido, Veerle De Bock, Juan R. Moreta, John Rimmer, Andrew R. D. Smedley, Lamine Boulkelia, Nis Jepsen, Paul Eriksen, Alkiviadis F. Bais, Vadim Shirotov, José M. Vilaplana, Keith M. Wilson, and Tomi Karppinen
Atmos. Chem. Phys., 18, 3885–3902, https://doi.org/10.5194/acp-18-3885-2018, https://doi.org/10.5194/acp-18-3885-2018, 2018
Short summary
Short summary
The European Brewer Network (EUBREWNET, COST Action ES1207) is comprised of close to 50 instruments and currently provides near-real-time ozone and UV data. Aerosols also play key role in the Earth–atmosphere system and introduce a large uncertainty into our understanding of climate change. In this work we describe and validate a method to incorporate the measurement of aerosols in EUBREWNET. We find that this Brewer network can provide reliable aerosol data across Europe in the UV range.
Stelios Kazadzis, Natalia Kouremeti, Henri Diémoz, Julian Gröbner, Bruce W. Forgan, Monica Campanelli, Victor Estellés, Kathleen Lantz, Joseph Michalsky, Thomas Carlund, Emilio Cuevas, Carlos Toledano, Ralf Becker, Stephan Nyeki, Panagiotis G. Kosmopoulos, Viktar Tatsiankou, Laurent Vuilleumier, Frederick M. Denn, Nozomu Ohkawara, Osamu Ijima, Philippe Goloub, Panagiotis I. Raptis, Michael Milner, Klaus Behrens, Africa Barreto, Giovanni Martucci, Emiel Hall, James Wendell, Bryan E. Fabbri, and Christoph Wehrli
Atmos. Chem. Phys., 18, 3185–3201, https://doi.org/10.5194/acp-18-3185-2018, https://doi.org/10.5194/acp-18-3185-2018, 2018
Short summary
Short summary
Aerosol optical depth measured from ground-based sun photometers is the most important parameter for studying the changes in the Earth's radiation balance due to aerosols. Representatives for various sun photometer types belonging to individual institutions or international aerosol networks gather every 5 years, for 3 weeks, in Davos, Switzerland, in order to compare their aeorosol optical depth retrievals. This work presents the results of the latest (fourth) filter radiometer intercomparison.
Panagiotis-Ioannis Raptis, Stelios Kazadzis, Julian Gröbner, Natalia Kouremeti, Lionel Doppler, Ralf Becker, and Constantinos Helmis
Atmos. Meas. Tech., 11, 1143–1157, https://doi.org/10.5194/amt-11-1143-2018, https://doi.org/10.5194/amt-11-1143-2018, 2018
Short summary
Short summary
The purpose of this work is to retrieve integrated water vapour using spectral measurements from Precision Solar Spectroradiometer (PSR). Two different approaches were developed one using single-channel direct sun irradiance measurements, and the second one integrating at a certain spectral region. The results of the spectral approach are closer to the retrievals of non-photometric techniques (GPS, microwave radiometer and radiosondes), suggesting this method provide more accurate IWV product.
Stelios Kazadzis, Natalia Kouremeti, Stephan Nyeki, Julian Gröbner, and Christoph Wehrli
Geosci. Instrum. Method. Data Syst., 7, 39–53, https://doi.org/10.5194/gi-7-39-2018, https://doi.org/10.5194/gi-7-39-2018, 2018
Short summary
Short summary
The World Optical Depth Research Calibration Center (WORCC) has been established after the recommendations of WMO for calibration of aerosol optical depth (AOD) -related sun photometers. WORCC is mandated to initiate homogenization activities among different AOD networks and to run a network (GAW-PFR) of sun photometers. To calibrate such instruments aiming at low measurement uncertainties the quality assurance, quality control and a basic hierarchy have to be defined and followed.
Christine Aebi, Julian Gröbner, Niklaus Kämpfer, and Laurent Vuilleumier
Atmos. Meas. Tech., 10, 4587–4600, https://doi.org/10.5194/amt-10-4587-2017, https://doi.org/10.5194/amt-10-4587-2017, 2017
Short summary
Short summary
The current study analyses the cloud radiative effect during the daytime depending on cloud fraction and cloud type at two stations in Switzerland over a time period of 3–5 years. Information about fractional cloud coverage and cloud type is retrieved from images taken by visible all-sky cameras. Cloud cover, cloud type and other atmospheric parameters have an influence on the magnitude of the longwave cloud effect as well as on the shortwave.
René Stübi, Herbert Schill, Jörg Klausen, Laurent Vuilleumier, Julian Gröbner, Luca Egli, and Dominique Ruffieux
Atmos. Meas. Tech., 10, 4479–4490, https://doi.org/10.5194/amt-10-4479-2017, https://doi.org/10.5194/amt-10-4479-2017, 2017
Short summary
Short summary
Long-term measurement series are the pillars of all climate change analysis. The Arosa total ozone series is the world's longest record, starting in 1926. To secure the future of these measurements, it is foreseen to move the instruments in Davos. To ascertain that the series will not be affected by this change, a multiyear campaign of parallel measurements on both sites has been done. The analysis of these data is presented and it is concluded that no discernible difference can be identified.
Stephan Nyeki, Stefan Wacker, Julian Gröbner, Wolfgang Finsterle, and Martin Wild
Atmos. Meas. Tech., 10, 3057–3071, https://doi.org/10.5194/amt-10-3057-2017, https://doi.org/10.5194/amt-10-3057-2017, 2017
Short summary
Short summary
A large number of radiometers used to measure solar and terrestrial broadband radiation are traceable to World Standard Groups at PMOD/WRC in Davos, Switzerland. A small correction of each group may be required in the future, and this study examines the methods and implications of this on data sets collected at four remote baseline stations since the 1990s. The goal is to develop a better estimate of the solar and terrestrial radiation budget at the Earth's surface.
Thomas Carlund, Natalia Kouremeti, Stelios Kazadzis, and Julian Gröbner
Atmos. Meas. Tech., 10, 905–923, https://doi.org/10.5194/amt-10-905-2017, https://doi.org/10.5194/amt-10-905-2017, 2017
Short summary
Short summary
Aerosols play an important role in atmospheric processes. Aerosol optical depth is the most common measure of columnar aerosol load. We present a sunphotometer called UVPFR that is able to measure aerosol optical depth in the ultraviolet range, including the calibration, characterization and validation of the instrument/measurements. The instrument will serve as a reference on the intercalibration of Brewer spectrophotometers that are also able to measure aerosol optical depth in the UV region.
Christos S. Zerefos, Kostas Eleftheratos, John Kapsomenakis, Stavros Solomos, Antje Inness, Dimitris Balis, Alberto Redondas, Henk Eskes, Marc Allaart, Vassilis Amiridis, Arne Dahlback, Veerle De Bock, Henri Diémoz, Ronny Engelmann, Paul Eriksen, Vitali Fioletov, Julian Gröbner, Anu Heikkilä, Irina Petropavlovskikh, Janusz Jarosławski, Weine Josefsson, Tomi Karppinen, Ulf Köhler, Charoula Meleti, Christos Repapis, John Rimmer, Vladimir Savinykh, Vadim Shirotov, Anna Maria Siani, Andrew R. D. Smedley, Martin Stanek, and René Stübi
Atmos. Chem. Phys., 17, 551–574, https://doi.org/10.5194/acp-17-551-2017, https://doi.org/10.5194/acp-17-551-2017, 2017
Short summary
Short summary
The paper makes a convincing case that the Brewer network is capable of detecting enhanced SO2 columns, as observed, e.g., after volcanic eruptions. For this reason, large volcanic eruptions of the past decade have been used to detect and forecast SO2 plumes of volcanic origin using the Brewer and other ground-based networks, aided by satellite, trajectory analysis calculations and modelling.
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
Short summary
Short summary
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.
África Barreto, Emilio Cuevas, María-José Granados-Muñoz, Lucas Alados-Arboledas, Pedro M. Romero, Julian Gröbner, Natalia Kouremeti, Antonio F. Almansa, Tom Stone, Carlos Toledano, Roberto Román, Mikhail Sorokin, Brent Holben, Marius Canini, and Margarita Yela
Atmos. Meas. Tech., 9, 631–654, https://doi.org/10.5194/amt-9-631-2016, https://doi.org/10.5194/amt-9-631-2016, 2016
Short summary
Short summary
This paper presents the new photometer CE318-T, able to perform daytime and
night-time photometric measurements using the sun and the moon as light
sources. This new device permits a complete cycle of diurnal aerosol and water vapour measurements to be extracted, valuable to enhance atmospheric monitoring. We have also highlighted the ability of this new device to capture short-term atmospheric variations, critical for climate studies.
Y. Bühler, M. Marty, L. Egli, J. Veitinger, T. Jonas, P. Thee, and C. Ginzler
The Cryosphere, 9, 229–243, https://doi.org/10.5194/tc-9-229-2015, https://doi.org/10.5194/tc-9-229-2015, 2015
Short summary
Short summary
We are able to map snow depth over large areas ( > 100km2) using airborne digital photogrammetry. Digital photogrammetry is more economical than airborne Laser Scanning but slightly less accurate. Comparisons to independent snow depth measurements reveal an accuracy of about 30cm. Spatial continuous mapping of snow depth is a major step forward compared to point measurements usually applied today. Limitations are steep slopes (> 50°) and areas covered by trees and scrubs.
M. Lothon, F. Lohou, D. Pino, F. Couvreux, E. R. Pardyjak, J. Reuder, J. Vilà-Guerau de Arellano, P Durand, O. Hartogensis, D. Legain, P. Augustin, B. Gioli, D. H. Lenschow, I. Faloona, C. Yagüe, D. C. Alexander, W. M. Angevine, E Bargain, J. Barrié, E. Bazile, Y. Bezombes, E. Blay-Carreras, A. van de Boer, J. L. Boichard, A. Bourdon, A. Butet, B. Campistron, O. de Coster, J. Cuxart, A. Dabas, C. Darbieu, K. Deboudt, H. Delbarre, S. Derrien, P. Flament, M. Fourmentin, A. Garai, F. Gibert, A. Graf, J. Groebner, F. Guichard, M. A. Jiménez, M. Jonassen, A. van den Kroonenberg, V. Magliulo, S. Martin, D. Martinez, L. Mastrorillo, A. F. Moene, F. Molinos, E. Moulin, H. P. Pietersen, B. Piguet, E. Pique, C. Román-Cascón, C. Rufin-Soler, F. Saïd, M. Sastre-Marugán, Y. Seity, G. J. Steeneveld, P. Toscano, O. Traullé, D. Tzanos, S. Wacker, N. Wildmann, and A. Zaldei
Atmos. Chem. Phys., 14, 10931–10960, https://doi.org/10.5194/acp-14-10931-2014, https://doi.org/10.5194/acp-14-10931-2014, 2014
S. Kazadzis, I. Veselovskii, V. Amiridis, J. Gröbner, A. Suvorina, S. Nyeki, E. Gerasopoulos, N. Kouremeti, M. Taylor, A. Tsekeri, and C. Wehrli
Atmos. Meas. Tech., 7, 2013–2025, https://doi.org/10.5194/amt-7-2013-2014, https://doi.org/10.5194/amt-7-2013-2014, 2014
A. Stenke, C. R. Hoyle, B. Luo, E. Rozanov, J. Gröbner, L. Maag, S. Brönnimann, and T. Peter
Atmos. Chem. Phys., 13, 9713–9729, https://doi.org/10.5194/acp-13-9713-2013, https://doi.org/10.5194/acp-13-9713-2013, 2013
T. Egorova, E. Rozanov, J. Gröbner, M. Hauser, and W. Schmutz
Atmos. Chem. Phys., 13, 3811–3823, https://doi.org/10.5194/acp-13-3811-2013, https://doi.org/10.5194/acp-13-3811-2013, 2013
Related subject area
Subject: Others (Wind, Precipitation, Temperature, etc.) | Technique: Remote Sensing | Topic: Validation and Intercomparisons
Solar background radiation temperature calibration of a pure rotational Raman lidar
Exploring commercial Global Navigation Satellite System (GNSS) radio occultation (RO) products for planetary boundary layer studies in the Arctic
Research on atmospheric temperature fine measurements from the near surface to 60 km altitude based on an integrated lidar system
Testing ground-based observations of wave activity in the (lower and upper) atmosphere as possible (complementary) indicators of streamer events
Quality assessment of YUNYAO radio occultation data in the neutral atmosphere
Turbulence kinetic energy dissipation rate estimated from a WindCube Doppler lidar and the LQ7 1.3 GHz radar wind profiler in the convective boundary layer
Comparison of temperature and wind profiles between ground-based remote sensing observations and numerical weather prediction model in complex Alpine topography: the Meiringen campaign
Cluster analysis of vertical polarimetric radio occultation profiles and corresponding liquid and ice water paths from Global Precipitation Measurement (GPM) microwave data
Enhanced quantitative precipitation estimation through the opportunistic use of Ku TV-SAT links via a dual-channel procedure
The added value and potential of long-term radio occultation data for climatological wind field monitoring
Exploring dual-lidar mean and turbulence measurements over Perdigão's complex terrain
Description and validation of the Japanese algorithm for radiative flux and heating rate products with all four EarthCARE instruments: pre-launch test with A-Train
Atmospheric stability from microwave radiometer observations for on/offshore wind energy applications
Improving the estimate of higher-order moments from lidar observations near the top of the convective boundary layer
Closing the gap in the tropics: the added value of radio-occultation data for wind field monitoring across the Equator
Verification of weather-radar-based hail metrics with crowdsourced observations from Switzerland
Observing atmospheric rivers using GNSS radio occultation data
Atmospheric motion vector (AMV) error characterization and bias correction by leveraging independent lidar data: a simulation using an observing system simulation experiment (OSSE) and optical flow AMVs
Rotary-wing drone-induced flow – comparison of simulations with lidar measurements
Application of Doppler sodar in short-term forecasting of PM10 concentration in the air in Krakow (Poland)
Radiative closure tests of collocated hyperspectral microwave and infrared radiometers
Effects of clouds and aerosols on downwelling surface solar irradiance nowcasting and short-term forecasting
Verification of parameterizations for clear sky downwelling longwave irradiance in the Arctic
Global evaluation of fast radiative transfer model coefficients for early meteorological satellite sensors
GPROF V7 and beyond: assessment of current and potential future versions of the GPROF passive microwave precipitation retrievals against ground radar measurements over the continental US and the Pacific Ocean
Assessing sampling and retrieval errors of GPROF precipitation estimates over the Netherlands
Comparisons and quality control of wind observations in a mountainous city using wind profile radar and the Aeolus satellite
On the use of routine airborne observations for evaluation and monitoring of satellite observations of thermodynamic profiles
Daily satellite-based sunshine duration estimates over Brazil: validation and intercomparison
Statistical assessment of a Doppler radar model of TKE dissipation rate for low Richardson numbers
Extended validation of Aeolus winds with wind-profiling radars in Antarctica and Arctic Sweden
The impact of Aeolus winds on near-surface wind forecasts over tropical ocean and high-latitude regions
Long-term validation of Aeolus L2B wind products at Punta Arenas, Chile, and Leipzig, Germany
Turbulence kinetic energy dissipation rate: assessment of radar models from comparisons between 1.3 GHz wind profiler radar (WPR) and DataHawk UAV measurements
The impacts of assimilating Aeolus horizontal line-of-sight winds on numerical predictions of Hurricane Ida (2021) and a mesoscale convective system over the Atlantic Ocean
Evaluation of tropospheric water vapour and temperature profiles retrieved from MetOp-A by the Infrared and Microwave Sounding scheme
Validation of the Aeolus L2B wind product with airborne wind lidar measurements in the polar North Atlantic region and in the tropics
An improved vertical correction method for the inter-comparison and inter-validation of integrated water vapour measurements
An assessment of reprocessed GPS/MET observations spanning 1995–1997
Turbulence parameters measured by the Beijing mesosphere–stratosphere–troposphere radar in the troposphere and lower stratosphere with three models: comparison and analyses
Comparison of planetary boundary layer height from ceilometer with ARM radiosonde data
Behavior and mechanisms of Doppler wind lidar error in varying stability regimes
Inter-comparison of atmospheric boundary layer (ABL) height estimates from different profiling sensors and models in the framework of HyMeX-SOP1
Evaluation of Aeolus L2B wind product with wind profiling radar measurements and numerical weather prediction model equivalents over Australia
Comparison of global UV spectral irradiance measurements between a BTS CCD-array and a Brewer spectroradiometer
Scan strategies for wind profiling with Doppler lidar – an large-eddy simulation (LES)-based evaluation
Exploiting Aeolus level-2b winds to better characterize atmospheric motion vector bias and uncertainty
Modelling the spectral shape of continuous-wave lidar measurements in a turbulent wind tunnel
Three-way calibration checks using ground-based, ship-based, and spaceborne radars
Rainfall retrieval algorithm for commercial microwave links: stochastic calibration
Vasura Jayaweera, Robert J. Sica, Giovanni Martucci, and Alexander Haefele
Atmos. Meas. Tech., 18, 1461–1469, https://doi.org/10.5194/amt-18-1461-2025, https://doi.org/10.5194/amt-18-1461-2025, 2025
Short summary
Short summary
Our study presents a new method, the solar background calibration method, which improves temperature determinations in rotational Raman lidar systems. By utilizing background solar radiation, this technique offers more continuous and reliable temperatures independent of external measuring instruments. This new method enhances our ability to monitor and understand atmospheric trends and their association with climate change with greater accuracy.
Manisha Ganeshan, Dong L. Wu, Joseph A. Santanello, Jie Gong, Chi Ao, Panagiotis Vergados, and Kevin J. Nelson
Atmos. Meas. Tech., 18, 1389–1403, https://doi.org/10.5194/amt-18-1389-2025, https://doi.org/10.5194/amt-18-1389-2025, 2025
Short summary
Short summary
This study explores the potential of two newly launched commercial Global Navigation Satellite System (GNSS) radio occultation (RO) satellite missions for advancing Arctic lower-atmospheric studies. The products have a good sampling of the lower Arctic atmosphere and are useful to derive the planetary boundary layer (PBL) height during winter months. This research is a step towards closing the observation gap in polar regions due to the decomissioning of Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC-1) GNSS RO mission and the lack of high-latitude coverage by its successor (COSMIC-2).
Zhangjun Wang, Tiantian Guo, Xianxin Li, Chao Chen, Dong Liu, Luoyuan Qu, Hui Li, and Xiufen Wang
Atmos. Meas. Tech., 18, 1405–1414, https://doi.org/10.5194/amt-18-1405-2025, https://doi.org/10.5194/amt-18-1405-2025, 2025
Short summary
Short summary
A dual-field, integrated lidar system has been developed to detect atmospheric temperatures from the near surface to 60 km over Qingdao, China. Temperature profiles from the near surface to 60 km are derived by pure rotational Raman and Rayleigh scattering techniques using a single integrated lidar system. The results prove the system can make fine measurements of the atmospheric temperature profiles from the near surface to 60 km.
Michal Kozubek, Lisa Kuchelbacher, Jaroslav Chum, Tereza Sindelarova, Franziska Trinkl, and Katerina Podolska
Atmos. Meas. Tech., 18, 1373–1388, https://doi.org/10.5194/amt-18-1373-2025, https://doi.org/10.5194/amt-18-1373-2025, 2025
Short summary
Short summary
Waves are important as main drivers of different stratispheric patterns (streamers). We analyse changes in waves and infrasound characteristics related to streamers using continuous Doppler soundings and arrays of microbarometers in Czechia. Ground measurements using infrasound arrays showed that gravity wave propagation azimuths were more random during streamers than during calm conditions. Measurements in the ionosphere during streamers did not differ from those expected for the given time.
Xiaoze Xu, Wei Han, Jincheng Wang, Zhiqiu Gao, Fenghui Li, Yan Cheng, and Naifeng Fu
Atmos. Meas. Tech., 18, 1339–1353, https://doi.org/10.5194/amt-18-1339-2025, https://doi.org/10.5194/amt-18-1339-2025, 2025
Short summary
Short summary
Commercial Global Navigation Satellite System (GNSS) radio occultation (RO) satellites are generally cheap and can generate a large volume of globally distributed observations in a short period of time. To evaluate the practical application value of these data, we must assess their quality. We evaluate the quality of YUNYAO RO data. By using the “three-cornered hat” method and comparing with data from Metop-C and COSMIC-2, it was found that the YUNYAO GNSS-RO data are of high quality.
Hubert Luce and Masanori Yabuki
Atmos. Meas. Tech., 18, 1193–1208, https://doi.org/10.5194/amt-18-1193-2025, https://doi.org/10.5194/amt-18-1193-2025, 2025
Short summary
Short summary
Over a 3-week period, simultaneous measurements were conducted using a Doppler lidar and a 1.3 GHz radar wind profiler in Japan. Although the instruments had no range overlap, turbulence kinetic energy dissipation rates were estimated through various methods in convective boundary layers. Hourly averaged estimates showed good agreement, within a factor of approximately 2, suggesting that both instruments and methods provide consistent dissipation rate values.
Alexandre Bugnard, Martine Collaud Coen, Maxime Hervo, Daniel Leuenberger, Marco Arpagaus, and Samuel Monhart
Atmos. Meas. Tech., 18, 1039–1061, https://doi.org/10.5194/amt-18-1039-2025, https://doi.org/10.5194/amt-18-1039-2025, 2025
Short summary
Short summary
Temperature (T) and wind profiles were measured by a Doppler wind lidar and a microwave radiometer in Meiringen in a medium-sized Alpine valley. Ground-based T inversions and thermal winds were studied during the 10 months of the campaign. The comparison between the observations and the COSMO-1E model provides good model performance for monthly climatologies. T inversions are however frequently missed, and important differences for particular cases are found, especially for foehn events.
Jonas E. Katona, Manuel de la Torre Juárez, Terence L. Kubar, F. Joseph Turk, Kuo-Nung Wang, and Ramon Padullés
Atmos. Meas. Tech., 18, 953–970, https://doi.org/10.5194/amt-18-953-2025, https://doi.org/10.5194/amt-18-953-2025, 2025
Short summary
Short summary
Polarimetric radio occultations (PROs) use polarized radio signals from satellites to detect moisture and precipitation in Earth's atmosphere. By applying nonlinear regression and k-means cluster analysis to over 2 years of PRO and non-PRO data, this study shows how deviations from a refractivity model relate to vertical profiles of water vapor pressure (moisture) and that differences between components of PRO signals correlate directly with vertical profiles of water path (precipitation).
Louise Gelbart, Laurent Barthès, François Mercier-Tigrine, Aymeric Chazottes, and Cécile Mallet
Atmos. Meas. Tech., 18, 351–370, https://doi.org/10.5194/amt-18-351-2025, https://doi.org/10.5194/amt-18-351-2025, 2025
Short summary
Short summary
In this paper, we present and evaluate a new method for the quantitative estimation of precipitation from a low-cost sensor. Based on previous work measuring the attenuation of an electromagnetic signal from a broadcast television satellite, we make this approach more accurate so it can be easily deployed and used operationally in areas where rainfall measurements are critical for applications like flood monitoring. In this article, the method is validated in France and applied in Côte d'Ivoire.
Irena Nimac, Julia Danzer, and Gottfried Kirchengast
Atmos. Meas. Tech., 18, 265–286, https://doi.org/10.5194/amt-18-265-2025, https://doi.org/10.5194/amt-18-265-2025, 2025
Short summary
Short summary
Due to the shortcomings of available observations, having accurate global 3D wind fields remains a challenge. A promising option is radio occultation (RO) satellite data, which enable the derivation of winds based on wind approximations. We test how well RO winds describe the ERA5 winds. We separate the total wind difference into the approximation bias and the systematic difference between the two datasets. The results show the utility of RO winds for climate monitoring and analyses.
Isadora L. Coimbra, Jakob Mann, José M. L. M. Palma, and Vasco T. P. Batista
Atmos. Meas. Tech., 18, 287–303, https://doi.org/10.5194/amt-18-287-2025, https://doi.org/10.5194/amt-18-287-2025, 2025
Short summary
Short summary
Dual-lidar measurements are explored here as a cost-effective alternative for measuring the wind at great heights. From measurements at a mountainous site, we showed that this methodology can accurately capture mean wind speeds and turbulence under different flow conditions, and we recommended optimal lidar placement and sampling rates. This methodology allows the construction of vertical wind profiles up to 430 m, surpassing traditional meteorological mast heights and single-lidar capabilities.
Akira Yamauchi, Kentaroh Suzuki, Eiji Oikawa, Miho Sekiguchi, Takashi M. Nagao, and Haruma Ishida
Atmos. Meas. Tech., 17, 6751–6767, https://doi.org/10.5194/amt-17-6751-2024, https://doi.org/10.5194/amt-17-6751-2024, 2024
Short summary
Short summary
A Japanese team developed the Level 2 atmospheric radiation flux and heating rate product for EarthCARE, which offers vertical profiles of longwave and shortwave radiative fluxes and heating rates. This study outlines the algorithm for the radiative product and its comparative validation against satellite and ground-based observations. It also analyzes errors in radiative fluxes at various scales and their dependence on cloud type, with ice-containing clouds identified as a primary error source.
Domenico Cimini, Rémi Gandoin, Stephanie Fiedler, Claudia Acquistapace, Andrea Balotti, Sabrina Gentile, Edoardo Geraldi, Christine Knist, Pauline Martinet, Saverio T. Nilo, Giandomenico Pace, Bernhard Pospichal, and Filomena Romano
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-186, https://doi.org/10.5194/amt-2024-186, 2024
Revised manuscript accepted for AMT
Short summary
Short summary
Atmospheric stability indicates whether air vertical motion is dumped or amplified. This is important for wind energy applications as it affects wind turbine wakes and thus the yield of wind parks. The paper provides an assessment of stability metrics measured by ground-based microwave radiometers in different climatological conditions and with instrument types, on- and offshore. Results indicate that special precaution may be required offshore to achieve typical onshore performances.
Tessa E. Rosenberger, David D. Turner, Thijs Heus, Girish N. Raghunathan, Timothy J. Wagner, and Julia Simonson
Atmos. Meas. Tech., 17, 6595–6602, https://doi.org/10.5194/amt-17-6595-2024, https://doi.org/10.5194/amt-17-6595-2024, 2024
Short summary
Short summary
This work used model output to show that considering the changes in boundary layer depth over time in the calculations of variables such as fluxes and variance yields more accurate results than cases where calculations were done at a constant height. This work was done to improve future observations of these variables at the top of the boundary layer.
Julia Danzer, Magdalena Pieler, and Gottfried Kirchengast
Atmos. Meas. Tech., 17, 4979–4995, https://doi.org/10.5194/amt-17-4979-2024, https://doi.org/10.5194/amt-17-4979-2024, 2024
Short summary
Short summary
We investigated the potential of radio occultation (RO) data for climate-oriented wind field monitoring, focusing on the equatorial band within ±5° latitude. In this region, the geostrophic balance breaks down, and the equatorial balance approximation takes over. The study encourages the use of RO wind fields for mesoscale climate monitoring for the equatorial region, showing a small improvement in the troposphere when including the meridional wind in the zonal-mean total wind speed.
Jérôme Kopp, Alessandro Hering, Urs Germann, and Olivia Martius
Atmos. Meas. Tech., 17, 4529–4552, https://doi.org/10.5194/amt-17-4529-2024, https://doi.org/10.5194/amt-17-4529-2024, 2024
Short summary
Short summary
We present a verification of two products based on weather radars to detect the presence of hail and estimate its size. Radar products are remote detection of hail, so they must be verified against ground-based observations. We use reports from users of the Swiss Weather Services phone app to do the verification. We found that the product estimating the presence of hail provides fair results but that it should be recalibrated and that estimating the hail size with radar is more challenging.
Bahareh Rahimi and Ulrich Foelsche
Atmos. Meas. Tech. Discuss., https://doi.org/10.5194/amt-2024-81, https://doi.org/10.5194/amt-2024-81, 2024
Revised manuscript accepted for AMT
Short summary
Short summary
This study explores the use of GNSS-RO data to improve understanding of the vertical structure of humidity in Atmospheric Rivers (ARs). Specific humidity profiles and IWV values from GNSS-RO are evaluated to assess if this method offers additional insights into ARs' vertical characteristics. The results suggest that combining GNSS-RO data, with its high vertical resolution, with SSMI/S data, known for high horizontal resolution, provides a more complete view of the 3D structure of ARs.
Hai Nguyen, Derek Posselt, Igor Yanovsky, Longtao Wu, and Svetla Hristova-Veleva
Atmos. Meas. Tech., 17, 3103–3119, https://doi.org/10.5194/amt-17-3103-2024, https://doi.org/10.5194/amt-17-3103-2024, 2024
Short summary
Short summary
Accurate global wind estimation is crucial for weather prediction and environmental modeling. Our study investigates a method to refine atmospheric motion vectors (AMVs) by comparing them with high-precision active-sensor winds. Leveraging supervised learning, we discovered that using high-precision active-sensor data can significantly reduce biases in passive-sensor winds in addition to providing estimates of the wind errors, thereby improving their reliability.
Liqin Jin, Mauro Ghirardelli, Jakob Mann, Mikael Sjöholm, Stephan Thomas Kral, and Joachim Reuder
Atmos. Meas. Tech., 17, 2721–2737, https://doi.org/10.5194/amt-17-2721-2024, https://doi.org/10.5194/amt-17-2721-2024, 2024
Short summary
Short summary
Three-dimensional wind fields can be accurately measured by sonic anemometers. However, the traditional mast-mounted sonic anemometers are not flexible in various applications, which can be potentially overcome by drones. Therefore, we conducted a proof-of-concept study by applying three continuous-wave Doppler lidars to characterize the complex flow around a drone to validate the results obtained by CFD simulations. Both methods show good agreement, with a velocity difference of 0.1 m s-1.
Ewa Agnieszka Krajny, Leszek Ośródka, and Marek Jan Wojtylak
Atmos. Meas. Tech., 17, 2451–2464, https://doi.org/10.5194/amt-17-2451-2024, https://doi.org/10.5194/amt-17-2451-2024, 2024
Short summary
Short summary
The use of sodar data to support an air quality forecasting system is encouraging.
The sodar model is a complement to forecasting methods because it is useful due to its simplicity and speed of calculations. It does not require emission data, for which it is difficult to quickly verify temporal and spatial variability.
The use of simple formulas of regression models in forecasting, while maintaining their multivariate nature, facilitates the optimisation of the prediction process.
Lei Liu, Natalia Bliankinshtein, Yi Huang, John R. Gyakum, Philip M. Gabriel, Shiqi Xu, and Mengistu Wolde
Atmos. Meas. Tech., 17, 2219–2233, https://doi.org/10.5194/amt-17-2219-2024, https://doi.org/10.5194/amt-17-2219-2024, 2024
Short summary
Short summary
We conducted a radiance closure experiment using a unique combination of two hyperspectral radiometers, one operating in the microwave and the other in the infrared. By comparing the measurements of the two hyperspectrometers to synthetic radiance simulated from collocated atmospheric profiles, we affirmed the proper performance of the two instruments and quantified their radiometric uncertainty for atmospheric sounding applications.
Kyriakoula Papachristopoulou, Ilias Fountoulakis, Alkiviadis F. Bais, Basil E. Psiloglou, Nikolaos Papadimitriou, Ioannis-Panagiotis Raptis, Andreas Kazantzidis, Charalampos Kontoes, Maria Hatzaki, and Stelios Kazadzis
Atmos. Meas. Tech., 17, 1851–1877, https://doi.org/10.5194/amt-17-1851-2024, https://doi.org/10.5194/amt-17-1851-2024, 2024
Short summary
Short summary
The upgraded systems SENSE2 and NextSENSE2 focus on improving the quality of solar nowcasting and forecasting. SENSE2 provides real-time estimates of solar irradiance across a wide region every 15 min. NextSENSE2 offers short-term forecasts of irradiance up to 3 h ahead. Evaluation with actual data showed that the instantaneous comparison yields the most discrepancies due to the uncertainties of cloud-related information and satellite versus ground-based spatial representativeness limitations.
Giandomenico Pace, Alcide di Sarra, Filippo Cali Quaglia, Virginia Ciardini, Tatiana Di Iorio, Antonio Iaccarino, Daniela Meloni, Giovanni Muscari, and Claudio Scarchilli
Atmos. Meas. Tech., 17, 1617–1632, https://doi.org/10.5194/amt-17-1617-2024, https://doi.org/10.5194/amt-17-1617-2024, 2024
Short summary
Short summary
This study investigates the performances of 17 formulas to determine the clear sky longwave downward irradiance in the Arctic environment. The formulas need to be tuned to the environmental conditions of the studied region and, to date, few of them have been developed and/or tested in the Arctic. The best formulas provide biases and root mean squared errors respectively smaller than 1 and 5 W m-2. We intend to use these results to estimate the longwave cloud radiative perturbation.
Bruna Barbosa Silveira, Emma Catherine Turner, and Jérôme Vidot
Atmos. Meas. Tech., 17, 1279–1296, https://doi.org/10.5194/amt-17-1279-2024, https://doi.org/10.5194/amt-17-1279-2024, 2024
Short summary
Short summary
A fast radiative transfer model, used to speed up the full spectral simulation of meteorological satellite channels in weather forecast models, is tested using 25 000 modelled atmospheres. The differences between calculations from the fast and the high-resolution reference models are examined for nine historic weather satellite instruments. The study confirms that a reduced set of 83 atmospheric profiles is robust enough to estimate the scale of the differences obtained from the larger sample.
Simon Pfreundschuh, Clément Guilloteau, Paula J. Brown, Christian D. Kummerow, and Patrick Eriksson
Atmos. Meas. Tech., 17, 515–538, https://doi.org/10.5194/amt-17-515-2024, https://doi.org/10.5194/amt-17-515-2024, 2024
Short summary
Short summary
The latest version of the GPROF retrieval algorithm that produces global precipitation estimates using observations from the Global Precipitation Measurement mission is validated against ground-based radars. The validation shows that the algorithm accurately estimates precipitation on scales ranging from continental to regional. In addition, we validate candidates for the next version of the algorithm and identify principal challenges for further improving space-borne rain measurements.
Linda Bogerd, Hidde Leijnse, Aart Overeem, and Remko Uijlenhoet
Atmos. Meas. Tech., 17, 247–259, https://doi.org/10.5194/amt-17-247-2024, https://doi.org/10.5194/amt-17-247-2024, 2024
Short summary
Short summary
Algorithms merge satellite radiometer data from various frequency channels, each tied to a different footprint size. We studied the uncertainty associated with sampling (over the Netherlands using 4 years of data) as precipitation is highly variable in space and time by simulating ground-based data as satellite footprints. Though sampling affects precipitation estimates, it doesn’t explain all discrepancies. Overall, uncertainties in the algorithm seem more influential than how data is sampled.
Hua Lu, Min Xie, Wei Zhao, Bojun Liu, Tijian Wang, and Bingliang Zhuang
Atmos. Meas. Tech., 17, 167–179, https://doi.org/10.5194/amt-17-167-2024, https://doi.org/10.5194/amt-17-167-2024, 2024
Short summary
Short summary
Observations of vertical wind in regions with complex terrain are essential, but they are always sparse and have poor representation. Data verification and quality control are conducted on the wind profile radar and Aeolus wind products in this study, trying to compensate for the limitations of wind field observations. The results shed light on the comprehensive applications of multi-source wind profile data in complicated terrain regions with sparse ground-based wind observations.
Timothy J. Wagner, Thomas August, Tim Hultberg, and Ralph A. Petersen
Atmos. Meas. Tech., 17, 1–14, https://doi.org/10.5194/amt-17-1-2024, https://doi.org/10.5194/amt-17-1-2024, 2024
Short summary
Short summary
Commercial passenger and freight aircraft need to know the temperature and pressure of the environments they fly through in order to safely operate. In this paper, we investigate how these observations can be used to evaluate and monitor the performance of satellite observations. Normally weather balloons are used for this, but in places like the United States there are many more airplane flights than weather balloon launches. This makes it much easier to compare them to satellites.
Maria Lívia L. M. Gava, Simone M. S. Costa, and Anthony C. S. Porfírio
Atmos. Meas. Tech., 16, 5429–5441, https://doi.org/10.5194/amt-16-5429-2023, https://doi.org/10.5194/amt-16-5429-2023, 2023
Short summary
Short summary
This study assesses the effectiveness of two geostationary satellite-based sunshine duration datasets over Brazil. Statistical parameters were used to evaluate the performance of the products. The results showed generally good agreement between satellite and ground observations, with some regional discrepancies. Overall, both satellite products offer reliable data for various applications, which benefit from their high spatial resolution and low time latency.
Hubert Luce, Lakshmi Kantha, and Hiroyuki Hashiguchi
Atmos. Meas. Tech., 16, 5091–5101, https://doi.org/10.5194/amt-16-5091-2023, https://doi.org/10.5194/amt-16-5091-2023, 2023
Short summary
Short summary
The potential ability of clear air radars to measure turbulence kinetic energy (TKE) dissipation rate ε in the atmosphere is a major asset of these instruments because of their continuous measurements. In the present work, we successfully tested the relevance of a model relating ε to the width of the Doppler spectrum peak and wind shear for shear-generated turbulence and we provide a physical interpretation of an empirical model in this context.
Sheila Kirkwood, Evgenia Belova, Peter Voelger, Sourav Chatterjee, and Karathazhiyath Satheesan
Atmos. Meas. Tech., 16, 4215–4227, https://doi.org/10.5194/amt-16-4215-2023, https://doi.org/10.5194/amt-16-4215-2023, 2023
Short summary
Short summary
We compared 2 years of wind measurements by the Aeolus satellite with winds from two wind-profiler radars in Arctic Sweden and coastal Antarctica. Biases are similar in magnitude to results from other locations. They are smaller than in earlier studies due to more comparison points and improved criteria for data rejection. On the other hand, the standard deviation is somewhat higher because of degradation of the Aeolus lidar.
Haichen Zuo and Charlotte Bay Hasager
Atmos. Meas. Tech., 16, 3901–3913, https://doi.org/10.5194/amt-16-3901-2023, https://doi.org/10.5194/amt-16-3901-2023, 2023
Short summary
Short summary
Aeolus is a satellite equipped with a Doppler wind lidar to detect global wind profiles. This study evaluates the impact of Aeolus winds on surface wind forecasts over tropical oceans and high-latitude regions based on the ECMWF observing system experiments. We find that Aeolus can slightly improve surface wind forecasts for the region > 60° N, especially from day 5 onwards. For other study regions, the impact of Aeolus is nearly neutral or limited, which requires further investigation.
Holger Baars, Joshua Walchester, Elizaveta Basharova, Henriette Gebauer, Martin Radenz, Johannes Bühl, Boris Barja, Ulla Wandinger, and Patric Seifert
Atmos. Meas. Tech., 16, 3809–3834, https://doi.org/10.5194/amt-16-3809-2023, https://doi.org/10.5194/amt-16-3809-2023, 2023
Short summary
Short summary
In 2018, the Aeolus satellite of the European Space Agency (ESA) was launched to improve weather forecasts through global measurements of wind profiles. Given the novel lidar technique onboard, extensive validation efforts have been needed to verify the observations. For this reason, we performed long-term validation measurements in Germany and Chile. We found significant improvement in the data products due to a new algorithm version and can confirm the general validity of Aeolus observations.
Hubert Luce, Lakshmi Kantha, Hiroyuki Hashiguchi, Dale Lawrence, Abhiram Doddi, Tyler Mixa, and Masanori Yabuki
Atmos. Meas. Tech., 16, 3561–3580, https://doi.org/10.5194/amt-16-3561-2023, https://doi.org/10.5194/amt-16-3561-2023, 2023
Short summary
Short summary
Doppler radars can be used to estimate turbulence kinetic energy dissipation rates in the atmosphere. The performance of various models is evaluated from comparisons between UHF wind profiler and in situ measurements with UAVs. For the first time, we assess a model supposed to be valid for weak stratification or strong shear conditions. This model provides better agreements with in situ measurements than the classical model based on the hypothesis of a stable stratification.
Chengfeng Feng and Zhaoxia Pu
Atmos. Meas. Tech., 16, 2691–2708, https://doi.org/10.5194/amt-16-2691-2023, https://doi.org/10.5194/amt-16-2691-2023, 2023
Short summary
Short summary
This study demonstrates the positive impacts of assimilating Aeolus Mie-cloudy and Rayleigh-clear near-real-time horizontal line-of-sight winds on the analysis and forecasts of Hurricane Ida (2021) and a mesoscale convective system associated with an African easterly wave using the mesoscale community Weather Research and Forecasting model and the NCEP Gridpoint Statistical Interpolation-based three-dimensional ensemble-variational hybrid data assimilation system.
Tim Trent, Richard Siddans, Brian Kerridge, Marc Schröder, Noëlle A. Scott, and John Remedios
Atmos. Meas. Tech., 16, 1503–1526, https://doi.org/10.5194/amt-16-1503-2023, https://doi.org/10.5194/amt-16-1503-2023, 2023
Short summary
Short summary
Modern weather satellites provide essential information on our lower atmosphere's moisture content and temperature structure. This measurement record will span over 40 years, making it a valuable resource for climate studies. This study characterizes atmospheric temperature and humidity profiles from a European Space Agency climate project. Using weather balloon measurements, we demonstrated the performance of this dataset was within the tolerances required for future climate studies.
Benjamin Witschas, Christian Lemmerz, Alexander Geiß, Oliver Lux, Uwe Marksteiner, Stephan Rahm, Oliver Reitebuch, Andreas Schäfler, and Fabian Weiler
Atmos. Meas. Tech., 15, 7049–7070, https://doi.org/10.5194/amt-15-7049-2022, https://doi.org/10.5194/amt-15-7049-2022, 2022
Short summary
Short summary
In August 2018, the first wind lidar Aeolus was launched into space and has since then been providing data of the global wind field. The primary goal of Aeolus was the improvement of numerical weather prediction. To verify the quality of Aeolus wind data, DLR performed four airborne validation campaigns with two wind lidar systems. In this paper, we report on results from the two later campaigns, performed in Iceland and the tropics.
Olivier Bock, Pierre Bosser, and Carl Mears
Atmos. Meas. Tech., 15, 5643–5665, https://doi.org/10.5194/amt-15-5643-2022, https://doi.org/10.5194/amt-15-5643-2022, 2022
Short summary
Short summary
Integrated water vapour measurements are often compared for the calibration and validation of instruments or techniques. Measurements made at different altitudes must be corrected to account for the vertical variation of water vapour. This paper shows that the widely used empirical correction model has severe limitations that are overcome using the proposed model. The method is applied to the inter-comparison of GPS and satellite microwave radiometer data in a tropical mountainous area.
Anthony J. Mannucci, Chi O. Ao, Byron A. Iijima, Thomas K. Meehan, Panagiotis Vergados, E. Robert Kursinski, and William S. Schreiner
Atmos. Meas. Tech., 15, 4971–4987, https://doi.org/10.5194/amt-15-4971-2022, https://doi.org/10.5194/amt-15-4971-2022, 2022
Short summary
Short summary
The Global Positioning System (GPS) radio occultation (RO) technique is a satellite-based method for producing highly accurate vertical profiles of atmospheric temperature and pressure. RO profiles are used to monitor global climate trends, particularly in that region of the atmosphere that includes the lower stratosphere. Two data sets spanning 1995–1997 that were produced from the first RO satellite are highly accurate and can be used to assess global atmospheric models.
Ze Chen, Yufang Tian, Yinan Wang, Yongheng Bi, Xue Wu, Juan Huo, Linjun Pan, Yong Wang, and Daren Lü
Atmos. Meas. Tech., 15, 4785–4800, https://doi.org/10.5194/amt-15-4785-2022, https://doi.org/10.5194/amt-15-4785-2022, 2022
Short summary
Short summary
Small-scale turbulence plays a vital role in the vertical exchange of heat, momentum and mass in the atmosphere. There are currently three models that can use spectrum width data of MST radar to calculate turbulence parameters. However, few studies have explored the applicability of the three calculation models. We compared and analysed the turbulence parameters calculated by three models. These results can provide a reference for the selection of models for calculating turbulence parameters.
Damao Zhang, Jennifer Comstock, and Victor Morris
Atmos. Meas. Tech., 15, 4735–4749, https://doi.org/10.5194/amt-15-4735-2022, https://doi.org/10.5194/amt-15-4735-2022, 2022
Short summary
Short summary
The planetary boundary layer is the lowest part of the atmosphere. Its structure and depth (PBLHT) significantly impact air quality, global climate, land–atmosphere interactions, and a wide range of atmospheric processes. To test the robustness of the ceilometer-estimated PBLHT under different atmospheric conditions, we compared ceilometer- and radiosonde-estimated PBLHTs using multiple years of U.S. DOE ARM measurements at various ARM observatories located around the world.
Rachel Robey and Julie K. Lundquist
Atmos. Meas. Tech., 15, 4585–4622, https://doi.org/10.5194/amt-15-4585-2022, https://doi.org/10.5194/amt-15-4585-2022, 2022
Short summary
Short summary
Our work investigates the behavior of errors in remote-sensing wind lidar measurements due to turbulence. Using a virtual instrument, we measured winds in simulated atmospheric flows and decomposed the resulting error. Dominant error mechanisms, particularly vertical velocity variations and interactions with shear, were identified in ensemble data over three test cases. By analyzing the underlying mechanisms, the response of the error behavior to further varying flow conditions may be projected.
Donato Summa, Fabio Madonna, Noemi Franco, Benedetto De Rosa, and Paolo Di Girolamo
Atmos. Meas. Tech., 15, 4153–4170, https://doi.org/10.5194/amt-15-4153-2022, https://doi.org/10.5194/amt-15-4153-2022, 2022
Short summary
Short summary
The evolution of the atmospheric boundary layer height (ABLH) has an important impact on meteorology. However, the complexity of the phenomena occurring within the ABL and the influence of advection and local accumulation processes often prevent an unambiguous determination of the ABLH. The paper reports results from an inter-comparison effort involving different sensors and techniques to measure the ABLH. Correlations between the ABLH and other atmospheric variables are also assessed.
Haichen Zuo, Charlotte Bay Hasager, Ioanna Karagali, Ad Stoffelen, Gert-Jan Marseille, and Jos de Kloe
Atmos. Meas. Tech., 15, 4107–4124, https://doi.org/10.5194/amt-15-4107-2022, https://doi.org/10.5194/amt-15-4107-2022, 2022
Short summary
Short summary
The Aeolus satellite was launched in 2018 for global wind profile measurement. After successful operation, the error characteristics of Aeolus wind products have not yet been studied over Australia. To complement earlier validation studies, we evaluated the Aeolus Level-2B11 wind product over Australia with ground-based wind profiling radar measurements and numerical weather prediction model equivalents. The results show that the Aeolus can detect winds with sufficient accuracy over Australia.
Carmen González, José M. Vilaplana, José A. Bogeat, and Antonio Serrano
Atmos. Meas. Tech., 15, 4125–4133, https://doi.org/10.5194/amt-15-4125-2022, https://doi.org/10.5194/amt-15-4125-2022, 2022
Short summary
Short summary
Monitoring ultraviolet (UV) radiation is important since it can have harmful effects on the biosphere. Array spectroradiometers are increasingly used to measure UV as they are more versatile than scanning spectroradiometers. In this study, the long-term performance of the BTS-2048-UV-S-WP array spectroradiometer was assessed. The results show that the BTS can reliably measure both the UV index and UV radiation in the 300–360 nm range. Moreover, the BTS was stable and showed no seasonal behavior.
Charlotte Rahlves, Frank Beyrich, and Siegfried Raasch
Atmos. Meas. Tech., 15, 2839–2856, https://doi.org/10.5194/amt-15-2839-2022, https://doi.org/10.5194/amt-15-2839-2022, 2022
Short summary
Short summary
Lidars can measure the wind profile in the lower part of the atmosphere, provided that the wind field is horizontally uniform and does not change during the time of the measurement. These requirements are mostly not fulfilled in reality, and the lidar wind measurement will thus hold a certain error. We investigate different strategies for lidar wind profiling using a lidar simulator implemented in a numerical simulation of the wind field. Our findings can help to improve wind measurements.
Katherine E. Lukens, Kayo Ide, Kevin Garrett, Hui Liu, David Santek, Brett Hoover, and Ross N. Hoffman
Atmos. Meas. Tech., 15, 2719–2743, https://doi.org/10.5194/amt-15-2719-2022, https://doi.org/10.5194/amt-15-2719-2022, 2022
Short summary
Short summary
Winds that are crucial to weather forecasting derived from two different techniques – tracking satellite images (AMVs) and direct measurement of molecular and aerosol motions by Doppler lidar (Aeolus satellite winds) – are compared. We find that AMVs and Aeolus winds are highly correlated. Aeolus Mie-cloudy winds have great potential value as a comparison standard for AMVs. Larger differences are found in the Southern Hemisphere related to higher wind speed and higher vertical variation in wind.
Marijn Floris van Dooren, Anantha Padmanabhan Kidambi Sekar, Lars Neuhaus, Torben Mikkelsen, Michael Hölling, and Martin Kühn
Atmos. Meas. Tech., 15, 1355–1372, https://doi.org/10.5194/amt-15-1355-2022, https://doi.org/10.5194/amt-15-1355-2022, 2022
Short summary
Short summary
The remote sensing technique lidar is widely used for wind speed measurements for both industrial and academic applications. Lidars can measure wind statistics accurately but cannot fully capture turbulent fluctuations in the high-frequency range, since they are partly filtered out. This paper therefore investigates the turbulence spectrum measured by a continuous-wave lidar and analytically models the lidar's measured spectrum with a Lorentzian filter function and a white noise term.
Alain Protat, Valentin Louf, Joshua Soderholm, Jordan Brook, and William Ponsonby
Atmos. Meas. Tech., 15, 915–926, https://doi.org/10.5194/amt-15-915-2022, https://doi.org/10.5194/amt-15-915-2022, 2022
Short summary
Short summary
This study uses collocated ship-based, ground-based, and spaceborne radar observations to validate the concept of using the GPM spaceborne radar observations to calibrate national weather radar networks to the accuracy required for operational severe weather applications such as rainfall and hail nowcasting.
Wagner Wolff, Aart Overeem, Hidde Leijnse, and Remko Uijlenhoet
Atmos. Meas. Tech., 15, 485–502, https://doi.org/10.5194/amt-15-485-2022, https://doi.org/10.5194/amt-15-485-2022, 2022
Short summary
Short summary
The existing infrastructure for cellular communication is promising for ground-based rainfall remote sensing. Rain-induced signal attenuation is used in dedicated algorithms for retrieving rainfall depth along commercial microwave links (CMLs) between cell phone towers. This processing is a source of many uncertainties about input data, algorithm structures, parameters, CML network, and local climate. Application of a stochastic optimization method leads to improved CML rainfall estimates.
Cited articles
Ångström, A.: Apparent solar constant variations and their relation to the variability of atmospheric transmission, Tellus, XXII, 205–218, 1970.
Bais, A. F.: Absolute spectral measurements of direct solar ultraviolet irradiance with a Brewer spectrophotometer, Appl. Optics, 36, 5199–5204, 1997.
Bolsée, D., Pereira, N., Decuyper, W., Gillotay, D., Yu, H., Sperfeld, P., Pape, S., Cuevas, E., Redondas, A., Hernandéz, Y., and Weber, M.: Accurate determination of the TOA Solar Spectral NIR irradiance using a primary standard source and the Bouguer-Langley technique, Sol. Phys., 289, 2433–2457, https://doi.org/10.1007/s11207-014-0474-1, 2014.
Bolsée, D., Pereira, N., Gillotay, D., Pandey, P., Cessateur, G., Foujols, T., Bekki, S., Hauchecorne, A., Meftah, M., Damé, L., Hersé, M., Michel, A., Jacobs, C., and Sela, A.: SOLAR/SOLSPEC mission on ISS: in-flight performance for SSI measurements in the UV, Astron. Astrophys., 600, A21, https://doi.org/10.1051/0004-6361/201628234, 2017.
Cebula, R. P., Thuillet, G. O., VanHoosier, M. E., Hilsenrath, E., Herse, M., Brueckner, G. E., and Simon, P. C.: Observations of the solar irradiance in the 200–350 nm interval during the ATLAS-1 mission: a comparison among three sets of measurements SSBUV, SOLSPEC, and SUSIM, Geophys. Res. Lett., 23, 2289–2292, 1996.
Chance, K. and Kurucz, R. L.: An improved high-resolution solar reference spectrum for earth's atmosphere measurements in the ultraviolet, visible and near infrared, J. Quant. Spectrosc. Ra., 111, 1289–1295, 2010.
Egli, L., Gröbner, J., and Shapiro, A.: Development of a New High Resolution Extraterrestrial Spectrum, in Annual report PMOD/WRC 2012, available at: http://www.pmodwrc.ch/annual_report/2012_PMODWRC_Annual_Report.pdf (last access: September 2017), 2012.
Fontenla, J. M., Avrett, E., Thuillier, G., and Harder, J.: Semiempirical models of the solar atmosphere. I. The quiet- and active sun photosphere at moderate resolution, Astrophys. J., 639, 441–458, 2006.
Gröbner, J. and Kerr, J.: Ground-based determination of the spectral ultraviolet extraterrestrial solar irradiance: Providing a link between space-based and ground-based solar UV measurements, J. Geophys. Res., 106, 7211–7217, 2001.
Gröbner, J., Schreder, J., Kazadzis, S., Bais, A. F., Blumthaler, M., Görts, P., Tax, R., Koskela, T., Seckmeyer, G., Webb, A. R., and Rembges, D.: Traveling reference spectroradiometer for routine quality assurance of spectral solar ultraviolet irradiance measurements, Appl. Optics, 44, 5321–5331, 2005.
Gueymard, C. A.: The sun's total and spectral irradiance for solar energy applications and solar radiation models, Sol. Energy, 76, 423–453, 2003.
Harder, J. W., Fontenla, J. M., Pilewskie, P., Richard, E. C., and Woods, T. N.: Trends in solar spectral irradiance variability in the visible and infrared, Geophys. Res. Lett., 36, L07801, https://doi.org/10.1029/2008GL036797, 2009.
Harder, J. W., Thuillier, G., Richard, E. C., Brown, S. W., Lykke, K. R., Snow, M., McClintock, W. E., Fontenla, J. M., Woods, T. N., and Pilewskie, P.: The SORCE SIM solar spectrum: comparison with recent observations, Sol. Phys., 263, 3–24, https://doi.org/10.1007/s11207-010-9555-y, 2010.
Hilbig, T., Weber, M., Bramstadt, K., Noël, S., Burrows, J. P., Krijger, J. M., Snel, R., Meftah, M., Damé, L., Bekki, S., Bolsée, D., Pereira, N., and Sluse, D.: The new SCIAMACHY reference solar spectral irradiance and its validation, Sol. Phys., submitted, 2017.
Hülsen, G., Gröbner, J., Nevas, S., Sperfeld, P., Egli, L., Porrovecchio, G., and Smid, M.: Traceability of solar UV measurements using the QASUME reference spectroradiometer, Appl. Optics, 55, 26, 7265–7275, 2016.
Kurucz, R. L., Furenlid, I., Brault, J., and Testerman, L.: Solar Flux Atlas from 296 nm to 1300 nm, National Solar Observatory, Sunspot, New Mexico, 1984.
Mayer, B. and Kylling, A.: Technical note: The libRadtran software package for radiative transfer calculations – description and examples of use, Atmos. Chem. Phys., 5, 1855–1877, https://doi.org/10.5194/acp-5-1855-2005, 2005.
Meftah, M., Bolsée, D., Damé, K., Hauchecorne, A., Pereira, N., Irbah, A., Bekki, S., Cessateur, G., Foujols, T., and Thiéblemont, R.: Solar Irradiance from 165 to 400 nm in 2008 and UV Variations in Three Spectral Bands During Solar Cycle 24, Sol. Phys., 291, 3527–3547, https://doi.org/10.1007/s11207-016-0997-8, 2016.
Schmid, B. and Wehrli, C.: Comparison of Sun photometer calibration by use of the Langley technique and the standard lamp, Appl. Optics, 34, 4500–4512, 1995.
Schöll, M., Dudok de Wit, T., Kretzschmar, M., and Haberreiter, M.: Making of a solar spectral irradiance dataset I: Observations, uncertainties, and methods, J. Space Weather Spac., 6, A14, https://doi.org/10.1051/swsc/2016007, 2016.
Shapiro, A. I., Schmutz, W., Schoell, M., Haberreiter, M., and Rozanov, E.: NLTE solar irradiance modelling with the COSI code, Astron. Astrophys., 517, A48, https://doi.org/10.1051/0004-6361/200913987, 2010.
Shaw, G. E.: Sun photometry, B. Am. Meteorol. Soc., 64, 4–10, 1983.
Thuiller, G., Herse, M., Simon, P. C., Labs, D., Mandel, H., and Gillotay, D.: Observation of the UV solar spectral irradiance between 200 and 350 nm during the ATLAS I mission by the SOLSPEC spectrometer, Sol. Phys., 171, 283–302, 1997.
Thuillier, G., Hersé, M., Labs, D., Foujols, T., Peetermans, W., Gillotay, D., Simon, P. C., and Mandel, H.: The Solar Spectral Irradiance from 200 to 2400 nm as Measured by the SOLSPEC Spectrometer from the Atlas and Eureca Missions, Sol. Phys., 214, 1–22, 2003.
Short summary
We have produced a benchmark high-resolution solar extraterrestrial spectrum from ground-based measurements of direct solar irradiance in the wavelength range 300 to 500 nm. This spectrum can be used for model calculations and for validating solar spectra measured in space. The metrological traceability of this solar spectrum to the International System of Units (SI) is assured by an unbroken chain of calibrations traceable to the primary spectral irradiance standard of PTB.
We have produced a benchmark high-resolution solar extraterrestrial spectrum from ground-based...
