Articles | Volume 41, issue 1
https://doi.org/10.5194/angeo-41-197-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/angeo-41-197-2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Regular paper
| 
18 Apr 2023
Regular paper |
| 18 Apr 2023
| 18 Apr 2023
Identifying gravity waves launched by the Hunga Tonga–Hunga Ha′apai volcanic eruption in mesosphere/lower-thermosphere winds derived from CONDOR and the Nordic Meteor Radar Cluster
Institute of Applied Physics & Oeschger Center for Climate Change Research, Microwave Physics, University of Bern, Bern, Switzerland
Center for Space and Atmospheric Research and Department of Physical Sciences, Embry-Riddle Aeronautical University, Daytona Beach, Florida, USA
Alexander Kozlovsky
Sodankylä Geophysical Observatory, University of Oulu, Oulu, Finland
Zishun Qiao
Center for Space and Atmospheric Research and Department of Physical Sciences, Embry-Riddle Aeronautical University, Daytona Beach, Florida, USA
Witali Krochin
Institute of Applied Physics & Oeschger Center for Climate Change Research, Microwave Physics, University of Bern, Bern, Switzerland
Guochun Shi
Institute of Applied Physics & Oeschger Center for Climate Change Research, Microwave Physics, University of Bern, Bern, Switzerland
Johan Kero
Swedish Institute of Space Physics (IRF), Kiruna, Sweden
Masaki Tsutsumi
National Institute of Polar Research, Tachikawa, Japan
The Graduate University for Advanced Studies (SOKENDAI), Tokyo, Japan
Njål Gulbrandsen
Tromsø Geophysical Observatory, UiT – The Arctic University of Norway, Tromsø, Norway
Satonori Nozawa
Ionospheric and Magnetospheric Research,
Institute for Space-Earth Environment Research, Nagoya University, Nagoya, Japan
Mark Lester
Department of Physics & Astronomy, University of Leicester, Leicester, UK
Kathrin Baumgarten
Smart Ocean Technologies, Fraunhofer Institute for Ceramic Technologies and Systems IKTS, Rostock, Germany
Evgenia Belova
Swedish Institute of Space Physics (IRF), Kiruna, Sweden
Nicholas Mitchell
British Antarctic Survey, Cambridge, UK
Department of Electronic & Electrical Engineering, University of Bath, Bath, UK
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Gunter Stober, Kathrin Baumgarten, John P. McCormack, Peter Brown, and Jerry Czarnecki
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Franziska Schranz, Jonas Hagen, Gunter Stober, Klemens Hocke, Axel Murk, and Niklaus Kämpfer
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Guochun Shi, Hanli Liu, Masaki Tsutsumi, Njål Gulbrandsen, Alexander Kozlovsky, Dimitry Pokhotelov, Mark Lester, Christoph Jacobi, Kun Wu, and Gunter Stober
Atmos. Chem. Phys., 25, 9403–9430, https://doi.org/10.5194/acp-25-9403-2025, https://doi.org/10.5194/acp-25-9403-2025, 2025
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Concerns about climate change are growing due to its widespread impacts, including rising temperatures, extreme weather events, and disruptions to ecosystems. To address these challenges, urgent global action is needed to monitor the distribution of trace gases and understand their effects on the atmosphere.
Ales Kuchar, Gunter Stober, Dimitry Pokhotelov, Huixin Liu, Han-Li Liu, Manfred Ern, Damian Murphy, Diego Janches, Tracy Moffat-Griffin, Nicholas Mitchell, and Christoph Jacobi
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We studied how the healing of the Antarctic ozone layer is affecting winds high above the South Pole. Using ground-based radar, satellite data, and computer models, we found that winds in the upper atmosphere have become stronger over the past two decades. These changes appear to be linked to shifts in the lower atmosphere caused by ozone recovery. Our results show that human efforts to repair the ozone layer are also influencing climate patterns far above Earth’s surface.
Arthur Gauthier, Claudia Borries, Alexander Kozlovsky, Diego Janches, Peter Brown, Denis Vida, Christoph Jacobi, Damian Murphy, Masaki Tsutsumi, Njål Gulbrandsen, Satonori Nozawa, Mark Lester, Johan Kero, Nicholas Mitchell, Tracy Moffat-Griffin, and Gunter Stober
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EGUsphere, https://doi.org/10.5194/egusphere-2025-3070, https://doi.org/10.5194/egusphere-2025-3070, 2025
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Florian Günzkofer, Gunter Stober, Johan Kero, David R. Themens, Anders Tjulin, Njål Gulbrandsen, Masaki Tsutsumi, and Claudia Borries
Ann. Geophys., 43, 331–348, https://doi.org/10.5194/angeo-43-331-2025, https://doi.org/10.5194/angeo-43-331-2025, 2025
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This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
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J. Federico Conte, Jorge L. Chau, Toralf Renkwitz, Ralph Latteck, Masaki Tsutsumi, Christoph Jacobi, Njål Gulbrandsen, and Satonori Nozawa
EGUsphere, https://doi.org/10.5194/egusphere-2025-1996, https://doi.org/10.5194/egusphere-2025-1996, 2025
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Pekka T. Verronen, Akira Mizuno, Yoshizumi Miyoshi, Sandeep Kumar, Taku Nakajima, Shin-Ichiro Oyama, Tomoo Nagahama, Satonori Nozawa, Monika E. Szelag, Tuomas Häkkilä, Niilo Kalakoski, Antti Kero, Esa Turunen, Satoshi Kasahara, Shoichiro Yokota, Kunihiro Keika, Tomoaki Hori, Takefumi Mitani, Takeshi Takashima, and Iku Shinohara
EGUsphere, https://doi.org/10.5194/egusphere-2025-1691, https://doi.org/10.5194/egusphere-2025-1691, 2025
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We use NO column density data from the Syowa station in Antarctica from 2012–2017. We compare these ground-based radiometer observations with results from a global atmosphere model to understand the year-to-year and day-to-day variability, shortcomings of current electron forcing, and how geomagnetic storms are driving the variability of NO. Our results demonstrate an underestimation in the magnitude of day-to-day variability in simulations, which calls for improved electron forcing in models.
Alistair Bell, Axel Murk, and Gunter Stober
EGUsphere, https://doi.org/10.5194/egusphere-2025-1396, https://doi.org/10.5194/egusphere-2025-1396, 2025
Short summary
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Increases in middle atmospheric water vapour from the 2022 Hunga eruption have been measured worldwide. This study uses remote sensing measurements at two latitudes and accurate radiative transfer modeling to show significant long-wave heating effects. Though minimal at the surface, the water vapour enhancement can alter middle-atmospheric dynamics, potentially affecting ozone chemistry and weather patterns.
Zishun Qiao, Alan Z. Liu, Gunter Stober, Javier Fuentes, Fabio Vargas, Christian L. Adami, and Iain M. Reid
Atmos. Meas. Tech., 18, 1091–1104, https://doi.org/10.5194/amt-18-1091-2025, https://doi.org/10.5194/amt-18-1091-2025, 2025
Short summary
Short summary
This paper describes the installation of the Chilean Observation Network De Meteor Radars (CONDOR) and its initial results. The routine winds are point-to-point comparable to the co-located lidar winds. The retrievals of spatially resolved horizontal wind fields and vertical winds are also facilitated, benefiting from the extensive meteor detections. The successful deployment and maintenance of CONDOR provide 24/7 and state-of-the-art wind measurements to the research community.
Alistair Bell, Eric Sauvageat, Gunter Stober, Klemens Hocke, and Axel Murk
Atmos. Meas. Tech., 18, 555–567, https://doi.org/10.5194/amt-18-555-2025, https://doi.org/10.5194/amt-18-555-2025, 2025
Short summary
Short summary
Hardware and software developments have been made on a 22 GHz microwave radiometer for the measurement of middle-atmospheric water vapour near Bern, Switzerland. Previous measurements dating back to 2010 have been re-calibrated and an improved optimal estimation retrieval performed on these measurements, giving a 13-year dataset. Measurements made with new and improved instrumental hardware are used to correct previous measurements, which show better agreement than the non-corrected dataset.
Guochun Shi, Witali Krochin, Eric Sauvageat, and Gunter Stober
Atmos. Chem. Phys., 24, 10187–10207, https://doi.org/10.5194/acp-24-10187-2024, https://doi.org/10.5194/acp-24-10187-2024, 2024
Short summary
Short summary
Here we investigated ozone anomalies over polar regions during sudden stratospheric and final stratospheric warming with ground-based microwave radiometers at polar latitudes compared with reanalysis and satellite data. The underlying dynamical and chemical mechanisms are responsible for the observed ozone anomalies in both events. Our research sheds light on these processes, emphasizing the need for a deeper understanding of these processes for more accurate climate modeling and forecasting.
Witali Krochin, Axel Murk, and Gunter Stober
Atmos. Meas. Tech., 17, 5015–5028, https://doi.org/10.5194/amt-17-5015-2024, https://doi.org/10.5194/amt-17-5015-2024, 2024
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Atmospheric tides are global-scale oscillations with periods of a fraction of a day. Their observation in the middle atmosphere is challenging and rare, as it requires continuous measurements with a high temporal resolution. In this paper, temperature time series of a ground-based microwave radiometer were analyzed with a spectral filter to derive thermal tide amplitudes and phases in an altitude range of 25–50 km at the geographical locations of Payerne and Bern (Switzerland).
Tinna L. Gunnarsdottir, Ingrid Mann, Wuhu Feng, Devin R. Huyghebaert, Ingemar Haeggstroem, Yasunobu Ogawa, Norihito Saito, Satonori Nozawa, and Takuya D. Kawahara
Ann. Geophys., 42, 213–228, https://doi.org/10.5194/angeo-42-213-2024, https://doi.org/10.5194/angeo-42-213-2024, 2024
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Several tons of meteoric particles burn up in our atmosphere each day. This deposits a great deal of material that binds with other atmospheric particles and forms so-called meteoric smoke particles. These particles are assumed to influence radar measurements. Here, we have compared radar measurements with simulations of a radar spectrum with and without dust particles and found that dust influences the radar spectrum in the altitude range of 75–85 km.
Gunter Stober, Sharon L. Vadas, Erich Becker, Alan Liu, Alexander Kozlovsky, Diego Janches, Zishun Qiao, Witali Krochin, Guochun Shi, Wen Yi, Jie Zeng, Peter Brown, Denis Vida, Neil Hindley, Christoph Jacobi, Damian Murphy, Ricardo Buriti, Vania Andrioli, Paulo Batista, John Marino, Scott Palo, Denise Thorsen, Masaki Tsutsumi, Njål Gulbrandsen, Satonori Nozawa, Mark Lester, Kathrin Baumgarten, Johan Kero, Evgenia Belova, Nicholas Mitchell, Tracy Moffat-Griffin, and Na Li
Atmos. Chem. Phys., 24, 4851–4873, https://doi.org/10.5194/acp-24-4851-2024, https://doi.org/10.5194/acp-24-4851-2024, 2024
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On 15 January 2022, the Hunga Tonga-Hunga Ha‘apai volcano exploded in a vigorous eruption, causing many atmospheric phenomena reaching from the surface up to space. In this study, we investigate how the mesospheric winds were affected by the volcanogenic gravity waves and estimated their propagation direction and speed. The interplay between model and observations permits us to gain new insights into the vertical coupling through atmospheric gravity waves.
Peter Dalin, Urban Brändström, Johan Kero, Peter Voelger, Takanori Nishiyama, Trond Trondsen, Devin Wyatt, Craig Unick, Vladimir Perminov, Nikolay Pertsev, and Jonas Hedin
Atmos. Meas. Tech., 17, 1561–1576, https://doi.org/10.5194/amt-17-1561-2024, https://doi.org/10.5194/amt-17-1561-2024, 2024
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A novel infrared imaging instrument (OH imager) was put into operation in November 2022 at the Swedish Institute of Space Physics in Kiruna (Sweden). The OH imager is dedicated to the study of nightglow emissions coming from the hydroxyl (OH) and molecular oxygen (O2) layers in the mesopause (80–100 km). Based on a brightness ratio of two OH emission lines, the neutral temperature is estimated at around 87 km. The average daily winter temperature for the period January–April 2023 is 203±10 K.
Florian Günzkofer, Gunter Stober, Dimitry Pokhotelov, Yasunobu Miyoshi, and Claudia Borries
Atmos. Meas. Tech., 16, 5897–5907, https://doi.org/10.5194/amt-16-5897-2023, https://doi.org/10.5194/amt-16-5897-2023, 2023
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Electric currents in the ionosphere can impact both satellite and ground-based infrastructure. These currents depend strongly on the collisions of ions and neutral particles. Measuring ion–neutral collisions is often only possible via certain assumptions. The direct measurement of ion–neutral collision frequencies is possible with multifrequency incoherent scatter radar measurements. This paper presents one analysis method of such measurements and discusses its advantages and disadvantages.
Juliana Jaen, Toralf Renkwitz, Huixin Liu, Christoph Jacobi, Robin Wing, Aleš Kuchař, Masaki Tsutsumi, Njål Gulbrandsen, and Jorge L. Chau
Atmos. Chem. Phys., 23, 14871–14887, https://doi.org/10.5194/acp-23-14871-2023, https://doi.org/10.5194/acp-23-14871-2023, 2023
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Investigation of winds is important to understand atmospheric dynamics. In the summer mesosphere and lower thermosphere, there are three main wind flows: the mesospheric westward, the mesopause southward (equatorward), and the lower-thermospheric eastward wind. Combining almost 2 decades of measurements from different radars, we study the trend, their interannual oscillations, and the effects of the geomagnetic activity over these wind maxima.
Florian Günzkofer, Dimitry Pokhotelov, Gunter Stober, Ingrid Mann, Sharon L. Vadas, Erich Becker, Anders Tjulin, Alexander Kozlovsky, Masaki Tsutsumi, Njål Gulbrandsen, Satonori Nozawa, Mark Lester, Evgenia Belova, Johan Kero, Nicholas J. Mitchell, and Claudia Borries
Ann. Geophys., 41, 409–428, https://doi.org/10.5194/angeo-41-409-2023, https://doi.org/10.5194/angeo-41-409-2023, 2023
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Gravity waves (GWs) are waves in Earth's atmosphere and can be observed as cloud ripples. Under certain conditions, these waves can propagate up into the ionosphere. Here, they can cause ripples in the ionosphere plasma, observable as oscillations of the plasma density. Therefore, GWs contribute to the ionospheric variability, making them relevant for space weather prediction. Additionally, the behavior of these waves allows us to draw conclusions about the atmosphere at these altitudes.
Guochun Shi, Witali Krochin, Eric Sauvageat, and Gunter Stober
Atmos. Chem. Phys., 23, 9137–9159, https://doi.org/10.5194/acp-23-9137-2023, https://doi.org/10.5194/acp-23-9137-2023, 2023
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We present the interannual and climatological behavior of ozone and water vapor from microwave radiometers in the Arctic.
By defining a virtual conjugate latitude station in the Southern Hemisphere, we investigate altitude-dependent interhemispheric differences and estimate the ascent and descent rates of water vapor in both hemispheres. Ozone and water vapor measurements will create a deeper understanding of the evolution of middle atmospheric ozone and water vapor.
Nobuo Matuura, Ryoichi Fujii, and Satonori Nozawa
Hist. Geo Space. Sci., 14, 61–69, https://doi.org/10.5194/hgss-14-61-2023, https://doi.org/10.5194/hgss-14-61-2023, 2023
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This paper describes the details of the Japan's participation in the EISCAT Radar Scientific Association as the 7th associate country approved in 1995, emphasizing strong collaboration with Norwegian scientists and the EISCAT Radar Scientific Association towards the realization of the Svalbard second antenna. Also described is a brief summary of Japanese EISCAT-related scientific achievement, comprehensive scientific collaborations so far between Japan and Europe, and hopes for EISCAT_3D.
Yuan Xia, Jing Jiao, Satonori Nozawa, Xuewu Cheng, Jihong Wang, Chunhua Shi, Lifang Du, Yajuan Li, Haoran Zheng, Faquan Li, and Guotao Yang
Atmos. Chem. Phys., 22, 13817–13831, https://doi.org/10.5194/acp-22-13817-2022, https://doi.org/10.5194/acp-22-13817-2022, 2022
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The layer of sodium atoms is generally located above 80 km. This study reports the significant enhancements of the sodium layer below 75 km where sodium atoms are short-lived. The neutral chemical reactions were suggested as making a critical contribution. The reported results provide clear observational evidence for the role of planetary waves in the variation of metal layers, and have implications for the response of the metal layers to perturbations in the lower atmosphere.
Gunter Stober, Alan Liu, Alexander Kozlovsky, Zishun Qiao, Ales Kuchar, Christoph Jacobi, Chris Meek, Diego Janches, Guiping Liu, Masaki Tsutsumi, Njål Gulbrandsen, Satonori Nozawa, Mark Lester, Evgenia Belova, Johan Kero, and Nicholas Mitchell
Atmos. Meas. Tech., 15, 5769–5792, https://doi.org/10.5194/amt-15-5769-2022, https://doi.org/10.5194/amt-15-5769-2022, 2022
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Precise and accurate measurements of vertical winds at the mesosphere and lower thermosphere are rare. Although meteor radars have been used for decades to observe horizontal winds, their ability to derive reliable vertical wind measurements was always questioned. In this article, we provide mathematical concepts to retrieve mathematically and physically consistent solutions, which are compared to the state-of-the-art non-hydrostatic model UA-ICON.
Li Dong, Hairu Ding, Guochun Shi, and Stephen J. Colucci
EGUsphere, https://doi.org/10.5194/egusphere-2022-1038, https://doi.org/10.5194/egusphere-2022-1038, 2022
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This paper investigated the spatial and temporal variations of static stability prior to blocking onsets. It quantified the relative contributions of static stability versus absolute vorticity in that processes. Based on the budget analysis, the decreasing static stability is found to be taken into account by the roles of horizontal advection, vertical advection, stretching effect and diabatic heating. In particular, the indirect effect of diabatic heating assumes an important role.
Mizuki Fukizawa, Takeshi Sakanoi, Yoshimasa Tanaka, Yasunobu Ogawa, Keisuke Hosokawa, Björn Gustavsson, Kirsti Kauristie, Alexander Kozlovsky, Tero Raita, Urban Brändström, and Tima Sergienko
Ann. Geophys., 40, 475–484, https://doi.org/10.5194/angeo-40-475-2022, https://doi.org/10.5194/angeo-40-475-2022, 2022
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The pulsating auroral generation mechanism has been investigated by observing precipitating electrons using rockets or satellites. However, it is difficult for such observations to distinguish temporal changes from spatial ones. In this study, we reconstructed the horizontal 2-D distribution of precipitating electrons using only auroral images. The 3-D aurora structure was also reconstructed. We found that there were both spatial and temporal changes in the precipitating electron energy.
Matthew J. Griffith and Nicholas J. Mitchell
Ann. Geophys., 40, 327–358, https://doi.org/10.5194/angeo-40-327-2022, https://doi.org/10.5194/angeo-40-327-2022, 2022
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There is great scientific interest in extending atmospheric models, such as the Met Office’s Unified Model, upwards to include the upper atmosphere. Atmospheric tides are an important driver of circulation at these greater heights. This study provides a first in-depth analysis of the migrating and non-migrating components of these tides, examining important tidal properties. Our results show that the ExUM produces a rich spectrum of spatial components, with significant non-migrating components.
Phoebe Noble, Neil Hindley, Corwin Wright, Chihoko Cullens, Scott England, Nicholas Pedatella, Nicholas Mitchell, and Tracy Moffat-Griffin
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2022-150, https://doi.org/10.5194/acp-2022-150, 2022
Revised manuscript not accepted
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We use long term radar data and the WACCM-X model to study the impact of dynamical phenomena, including the 11-year solar cycle, ENSO, QBO and SAM, on Antarctic mesospheric winds. We find that in summer, the zonal wind (both observationally and in the model) is strongly correlated with the solar cycle. We also see important differences in the results from the other processes. In addition we find important and large biases in the winter model zonal winds relative to the observations.
Witali Krochin, Francisco Navas-Guzmán, David Kuhl, Axel Murk, and Gunter Stober
Atmos. Meas. Tech., 15, 2231–2249, https://doi.org/10.5194/amt-15-2231-2022, https://doi.org/10.5194/amt-15-2231-2022, 2022
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This study leverages atmospheric temperature measurements performed with a ground-based radiometer making use of data that was collected during a 4-year observational campaign applying a new retrieval algorithm that improves the maximal altitude range from 45 to 55 km. The measurements are validated against two independent data sets, MERRA2 reanalysis data and the meteorological analysis of NAVGEM-HA.
Sumanta Sarkhel, Gunter Stober, Jorge L. Chau, Steven M. Smith, Christoph Jacobi, Subarna Mondal, Martin G. Mlynczak, and James M. Russell III
Ann. Geophys., 40, 179–190, https://doi.org/10.5194/angeo-40-179-2022, https://doi.org/10.5194/angeo-40-179-2022, 2022
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A rare gravity wave event was observed on the night of 25 April 2017 over northern Germany. An all-sky airglow imager recorded an upward-propagating wave at different altitudes in mesosphere with a prominent wave front above 91 km and faintly observed below. Based on wind and satellite-borne temperature profiles close to the event location, we have found the presence of a leaky thermal duct layer in 85–91 km. The appearance of this duct layer caused the wave amplitudes to diminish below 91 km.
Juliana Jaen, Toralf Renkwitz, Jorge L. Chau, Maosheng He, Peter Hoffmann, Yosuke Yamazaki, Christoph Jacobi, Masaki Tsutsumi, Vivien Matthias, and Chris Hall
Ann. Geophys., 40, 23–35, https://doi.org/10.5194/angeo-40-23-2022, https://doi.org/10.5194/angeo-40-23-2022, 2022
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To study long-term trends in the mesosphere and lower thermosphere (70–100 km), we established two summer length definitions and analyzed the variability over the years (2004–2020). After the analysis, we found significant trends in the summer beginning of one definition. Furthermore, we were able to extend one of the time series up to 31 years and obtained evidence of non-uniform trends and periodicities similar to those known for the quasi-biennial oscillation and El Niño–Southern Oscillation.
Christoph Jacobi, Friederike Lilienthal, Dmitry Korotyshkin, Evgeny Merzlyakov, and Gunter Stober
Adv. Radio Sci., 19, 185–193, https://doi.org/10.5194/ars-19-185-2021, https://doi.org/10.5194/ars-19-185-2021, 2021
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We compare winds and tidal amplitudes in the upper mesosphere/lower thermosphere region for cases with disturbed and undisturbed geomagnetic conditions. The zonal winds in both the mesosphere and lower thermosphere tend to be weaker during disturbed conditions. The summer equatorward meridional wind jet is weaker for disturbed geomagnetic conditions. The effect of geomagnetic variability on tidal amplitudes, except for the semidiurnal tide, is relatively small.
Gunter Stober, Alexander Kozlovsky, Alan Liu, Zishun Qiao, Masaki Tsutsumi, Chris Hall, Satonori Nozawa, Mark Lester, Evgenia Belova, Johan Kero, Patrick J. Espy, Robert E. Hibbins, and Nicholas Mitchell
Atmos. Meas. Tech., 14, 6509–6532, https://doi.org/10.5194/amt-14-6509-2021, https://doi.org/10.5194/amt-14-6509-2021, 2021
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Wind observations at the edge to space, 70–110 km altitude, are challenging. Meteor radars have become a widely used instrument to obtain mean wind profiles above an instrument for these heights. We describe an advanced mathematical concept and present a tomographic analysis using several meteor radars located in Finland, Sweden and Norway, as well as Chile, to derive the three-dimensional flow field. We show an example of a gravity wave decelerating the mean flow.
Gunter Stober, Ales Kuchar, Dimitry Pokhotelov, Huixin Liu, Han-Li Liu, Hauke Schmidt, Christoph Jacobi, Kathrin Baumgarten, Peter Brown, Diego Janches, Damian Murphy, Alexander Kozlovsky, Mark Lester, Evgenia Belova, Johan Kero, and Nicholas Mitchell
Atmos. Chem. Phys., 21, 13855–13902, https://doi.org/10.5194/acp-21-13855-2021, https://doi.org/10.5194/acp-21-13855-2021, 2021
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Little is known about the climate change of wind systems in the mesosphere and lower thermosphere at the edge of space at altitudes from 70–110 km. Meteor radars represent a well-accepted remote sensing technique to measure winds at these altitudes. Here we present a state-of-the-art climatological interhemispheric comparison using continuous and long-lasting observations from worldwide distributed meteor radars from the Arctic to the Antarctic and sophisticated general circulation models.
Joel P. Younger, Iain M. Reid, Chris L. Adami, Chris M. Hall, and Masaki Tsutsumi
Atmos. Meas. Tech., 14, 5015–5027, https://doi.org/10.5194/amt-14-5015-2021, https://doi.org/10.5194/amt-14-5015-2021, 2021
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A radar in Svalbard usually used to study meteor trails was used to observe a thin icy layer in the upper atmosphere. New methods used the layer to measure wind speed over short periods of time and found that the layer is most reflective within 6.8 ± 3.3° of vertical. Analysis of meteor trail radar echo durations found that the layer may shorten meteor trail echoes, but more data are needed. This study shows new uses for data collected by meteor radars for other purposes.
Nadezda Yagova, Alexander Kozlovsky, Evgeny Fedorov, and Olga Kozyreva
Ann. Geophys., 39, 549–562, https://doi.org/10.5194/angeo-39-549-2021, https://doi.org/10.5194/angeo-39-549-2021, 2021
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We present a study of ultralow-frequency waves in the ionosphere and on the ground. These waves are very slow (their periods are about several minutes). They are registered on the ground as geomagnetic pulsations. No simple dependence exists between geomagnetic and ionospheric pulsations. Here we study not only selected pulsations with very high amplitudes but also usual pulsations and try to answer the question, which pulsation parameters are favorable for modulation of the ionosphere?
Emranul Sarkar, Alexander Kozlovsky, Thomas Ulich, Ilkka Virtanen, Mark Lester, and Bernd Kaifler
Atmos. Meas. Tech., 14, 4157–4169, https://doi.org/10.5194/amt-14-4157-2021, https://doi.org/10.5194/amt-14-4157-2021, 2021
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The biasing effect in meteor radar temperature has been a pressing issue for the last 2 decades. This paper has addressed the underlying reasons for such a biasing effect on both theoretical and experimental grounds. An improved statistical method has been developed which allows atmospheric temperatures at around 90 km to be measured with meteor radar in an independent way such that any subsequent bias correction or calibration is no longer required.
Daniel Kastinen, Johan Kero, Alexander Kozlovsky, and Mark Lester
Atmos. Meas. Tech., 14, 3583–3596, https://doi.org/10.5194/amt-14-3583-2021, https://doi.org/10.5194/amt-14-3583-2021, 2021
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When a meteor enters the atmosphere, it causes a trail of diffusing plasma that moves with the neutral wind. An interferometric radar system can measure such trails and determine its location. However, there is a chance of determining the wrong position due to noise. We simulate this behaviour and use the simulations to successfully determine the true location of ambiguous events. We also successfully test two simple temporal integration methods for avoiding such erroneous determinations.
Viswanathan Lakshmi Narayanan, Satonori Nozawa, Shin-Ichiro Oyama, Ingrid Mann, Kazuo Shiokawa, Yuichi Otsuka, Norihito Saito, Satoshi Wada, Takuya D. Kawahara, and Toru Takahashi
Atmos. Chem. Phys., 21, 2343–2361, https://doi.org/10.5194/acp-21-2343-2021, https://doi.org/10.5194/acp-21-2343-2021, 2021
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In the past, additional sodium peaks occurring above the main sodium layer of the upper mesosphere were discussed. Here, formation of an additional sodium peak below the main sodium layer peak is discussed in detail. The event coincided with passage of multiple mesospheric bores, which are step-like disturbances occurring in the upper mesosphere. Hence, this work highlights the importance of such mesospheric bores in causing significant changes to the minor species concentration in a short time.
Gunter Stober, Diego Janches, Vivien Matthias, Dave Fritts, John Marino, Tracy Moffat-Griffin, Kathrin Baumgarten, Wonseok Lee, Damian Murphy, Yong Ha Kim, Nicholas Mitchell, and Scott Palo
Ann. Geophys., 39, 1–29, https://doi.org/10.5194/angeo-39-1-2021, https://doi.org/10.5194/angeo-39-1-2021, 2021
Daniel Kastinen and Johan Kero
Atmos. Meas. Tech., 13, 6813–6835, https://doi.org/10.5194/amt-13-6813-2020, https://doi.org/10.5194/amt-13-6813-2020, 2020
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The behaviour of position determination with interferometric radar systems and possible ambiguities therein depends on the spatial configuration of the radar-receiving antennas and their individual characteristics. We have simulated the position determination performance of five different radar systems. These simulations showed that ambiguities are dynamic and need to be examined on a case-by-case basis. However, the simulations can be used to analyse and understand previously ambiguous data.
Gunter Stober, Kathrin Baumgarten, John P. McCormack, Peter Brown, and Jerry Czarnecki
Atmos. Chem. Phys., 20, 11979–12010, https://doi.org/10.5194/acp-20-11979-2020, https://doi.org/10.5194/acp-20-11979-2020, 2020
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This paper presents a first cross-comparison of meteor ground-based observations and a meteorological analysis (NAVGEM-HA) to compare a seasonal climatology of winds and temperatures at the mesosphere/lower thermosphere. The validation is insofar unique as we not only compare the mean state but also provide a detailed comparison of the short time variability of atmospheric tidal waves. Our analysis questions previous results claiming the importance of lunar tides.
Leonie Bernet, Elmar Brockmann, Thomas von Clarmann, Niklaus Kämpfer, Emmanuel Mahieu, Christian Mätzler, Gunter Stober, and Klemens Hocke
Atmos. Chem. Phys., 20, 11223–11244, https://doi.org/10.5194/acp-20-11223-2020, https://doi.org/10.5194/acp-20-11223-2020, 2020
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With global warming, water vapour increases in the atmosphere. Water vapour is an important gas because it is a natural greenhouse gas and affects the formation of clouds, rain and snow. How much water vapour increases can vary in different regions of the world. To verify if it increases as expected on a regional scale, we analysed water vapour measurements in Switzerland. We found that water vapour generally increases as expected from temperature changes, except in winter.
Franziska Schranz, Jonas Hagen, Gunter Stober, Klemens Hocke, Axel Murk, and Niklaus Kämpfer
Atmos. Chem. Phys., 20, 10791–10806, https://doi.org/10.5194/acp-20-10791-2020, https://doi.org/10.5194/acp-20-10791-2020, 2020
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We measured middle-atmospheric ozone, water vapour and zonal and meridional wind with two ground-based microwave radiometers which are located at Ny-Alesund, Svalbard, in the Arctic. In this article we present measurements of the small-scale horizontal ozone gradients during winter 2018/2019. We found a distinct seasonal variation of the ozone gradients which is linked to the planetary wave activity. We further present the signatures of the SSW in the ozone, water vapour and wind measurements.
Cited articles
Becker, E. and Vadas, S. L.: Secondary Gravity Waves in the Winter Mesosphere:
Results From a High-Resolution Global Circulation Model, J.
Geophys. Res.-Atmos., 123, 2605–2627,
https://doi.org/10.1002/2017JD027460, 2018. a
Carr, J. L., Horváth, A., Wu, D. L., and Friberg, M. D.: Stereo Plume
Height and Motion Retrievals for the Record-Setting Hunga Tonga-Hunga Ha'apai
Eruption of 15 January 2022, Geophys. Res. Lett., 49,
e2022GL098131, https://doi.org/10.1029/2022GL098131, 2022. a
Gudadze, N., Stober, G., and Chau, J. L.: Can VHF radars at polar latitudes measure mean vertical winds in the presence of PMSE?, Atmos. Chem. Phys., 19, 4485–4497, https://doi.org/10.5194/acp-19-4485-2019, 2019. a
Heale, C. J., Inchin, P. A., and Snively, J. B.: Primary Versus Secondary
Gravity Wave Responses at F-Region Heights Generated by a Convective Source,
J. Geophys. Res.: Space Physics, 127, e2021JA029947,
https://doi.org/10.1029/2021JA029947, 2022. a
Heki, K.: Ionospheric signatures of repeated passages of atmospheric waves by the 2022 Jan. 15 Hunga Tonga-Hunga Ha’apai eruption detected by QZSS-TEC observations in Japan, Earth Planet. Space, 74, 112, https://doi.org/10.1186/s40623-022-01674-7, 2022. a, b
Klein, A.: Tongan volcano erupts, New Scientist, 253, 7,
https://doi.org/10.1016/S0262-4079(22)00074-4, 2022. a
Matoza, R. S., Fee, D., Assink, J. D., Iezzi, A. M., Green, D. N., Kim, K.,
Toney, L., Lecocq, T., Krishnamoorthy, S., Lalande, J.-M., Nishida, K., Gee,
K. L., Haney, M. M., Ortiz, H. D., Brissaud, Q., Martire, L., Rolland, L.,
Vergados, P., Nippress, A., Park, J., Shani-Kadmiel, S., Witsil, A.,
Arrowsmith, S., Caudron, C., Watada, S., Perttu, A. B., Taisne, B., Mialle,
P., Pichon, A. L., Vergoz, J., Hupe, P., Blom, P. S., Waxler, R., Angelis,
S. D., Snively, J. B., Ringler, A. T., Anthony, R. E., Jolly, A. D., Kilgour,
G., Averbuch, G., Ripepe, M., Ichihara, M., Arciniega-Ceballos, A.,
Astafyeva, E., Ceranna, L., Cevuard, S., Che, I.-Y., Negri, R. D., Ebeling,
C. W., Evers, L. G., Franco-Marin, L. E., Gabrielson, T. B., Hafner, K.,
Harrison, R. G., Komjathy, A., Lacanna, G., Lyons, J., Macpherson, K. A.,
Marchetti, E., McKee, K. F., Mellors, R. J., Mendo-Pérez, G., Mikesell,
T. D., Munaibari, E., Oyola-Merced, M., Park, I., Pilger, C., Ramos, C.,
Ruiz, M. C., Sabatini, R., Schwaiger, H. F., Tailpied, D., Talmadge, C.,
Vidot, J., Webster, J., and Wilson, D. C.: Atmospheric waves and global
seismoacoustic observations of the January 2022 Hunga eruption, Tonga,
Science, 377, 95–100, https://doi.org/10.1126/science.abo7063, 2022. a, b, c, d, e, f, g
Otsuka, S.: Visualizing Lamb Waves From a Volcanic Eruption Using
Meteorological Satellite Himawari-8, Geophys. Res. Lett., 49,
e2022GL098324, https://doi.org/10.1029/2022GL098324, 2022. a, b
Sarkhel, S., Stober, G., Chau, J. L., Smith, S. M., Jacobi, C., Mondal, S., Mlynczak, M. G., and Russell III, J. M.: A case study of a ducted gravity wave event over northern Germany using simultaneous airglow imaging and wind-field observations, Ann. Geophys., 40, 179–190, https://doi.org/10.5194/angeo-40-179-2022, 2022. a
Shannon, C. E.: A Mathematical Theory of Communication, Bell Syst. Tech.
J., 27, 379–423,
https://doi.org/10.1002/j.1538-7305.1948.tb01338.x, 1948. a
Smith, S. M., Stober, G., Jacobi, C., Chau, J. L., Gerding, M., Mlynczak,
M. G., Russell, J. M., Baumgardner, J. L., Mendillo, M., Lazzarin, M., and
Umbriaco, G.: Characterization of a Double Mesospheric Bore Over Europe,
J. Geophys. Res.-Space Phys., 122, 9738–9750,
https://doi.org/10.1002/2017JA024225, 2017. a
Stober, G., Kozlovsky, A., Liu, A., Qiao, Z., Tsutsumi, M., Hall, C., Nozawa, S., Lester, M., Belova, E., Kero, J., Espy, P. J., Hibbins, R. E., and Mitchell, N.: Atmospheric tomography using the Nordic Meteor Radar Cluster and Chilean Observation Network De Meteor Radars: network details and 3D-Var retrieval, Atmos. Meas. Tech., 14, 6509–6532, https://doi.org/10.5194/amt-14-6509-2021, 2021. a. a, b, c
Stober, G., Kuchar, A., Pokhotelov, D., Liu, H., Liu, H.-L., Schmidt, H., Jacobi, C., Baumgarten, K., Brown, P., Janches, D., Murphy, D., Kozlovsky, A., Lester, M., Belova, E., Kero, J., and Mitchell, N.: Interhemispheric differences of mesosphere–lower thermosphere winds and tides investigated from three whole-atmosphere models and meteor radar observations, Atmos. Chem. Phys., 21, 13855–13902, https://doi.org/10.5194/acp-21-13855-2021, 2021b. a
Stober, G., Liu, A., Kozlovsky, A., Qiao, Z., Kuchar, A., Jacobi, C., Meek, C., Janches, D., Liu, G., Tsutsumi, M., Gulbrandsen, N., Nozawa, S., Lester, M., Belova, E., Kero, J., and Mitchell, N.: Meteor radar vertical wind observation biases and mathematical debiasing strategies including the 3DVAR+DIV algorithm, Atmos. Meas. Tech., 15, 5769–5792, https://doi.org/10.5194/amt-15-5769-2022, 2022. a, b, c, d, e
Themens, D. R., Watson, C., Žagar, N., Vasylkevych, S., Elvidge, S.,
McCaffrey, A., Prikryl, P., Reid, B., Wood, A., and Jayachandran, P. T.:
Global Propagation of Ionospheric Disturbances Associated With the 2022 Tonga
Volcanic Eruption, Geophys. Res. Lett., 49, e2022GL098158,
https://doi.org/10.1029/2022GL098158, 2022. a, b
Vadas, S. L. and Becker, E.: Numerical Modeling of the Excitation, Propagation,
and Dissipation of Primary and Secondary Gravity Waves during Wintertime at
McMurdo Station in the Antarctic, J. Geophys. Res.-Atmos., 123, 9326–9369, https://doi.org/10.1029/2017JD027974, 2018.
a
Vadas, S. L., Zhao, J., Chu, X., and Becker, E.: The Excitation of Secondary
Gravity Waves From Local Body Forces: Theory and Observation, J.
Geophys. Res.-Atmos., 123, 9296–9325,
https://doi.org/10.1029/2017JD027970, 2018. a
Wilhelm, S., Stober, G., and Brown, P.: Climatologies and long-term changes in mesospheric wind and wave measurements based on radar observations at high and mid latitudes, Ann. Geophys., 37, 851–875, https://doi.org/10.5194/angeo-37-851-2019, 2019. a
Wright, C. J., Hindley, N. P., Alexander, M. J., Barlow, M., Hoffmann, L.,
Mitchell, C. N., Prata, F., Bouillon, M.and Carstens, J., Clerbaux, C.,
Osprey, S. M., Powell, N., Randall, C. E., and Yue, J.: Surface-to-space
atmospheric waves from Hunga Tonga-Hunga Ha’apai eruption, Nature, 609,
741–746, https://doi.org/10.1038/s41586-022-05012-5, 2022. a, b, c, d, e, f, g, h, i, j, k
Yamada, M., Ho, T.-C., Mori, J., Nishikawa, Y., and Yamamoto, M.-Y.: Tsunami
Triggered by the Lamb Wave From the 2022 Tonga Volcanic Eruption and
Transition in the Offshore Japan Region, Geophys. Res. Lett., 49,
e2022GL098752, https://doi.org/10.1029/2022GL098752, 2022. a, b, c
Zhang, S.-R., Vierinen, J., Aa, E., Goncharenko, L. P., Erickson, P. J.,
Rideout, W., Coster, A. J., and Spicher, A.: 2022 Tonga volcanic eruption
induced global propagation of ionospheric disturbances via Lamb waves, Front. Astron. Space Sci., 9, 871275,
https://doi.org/10.3389/fspas.2022.871275, 2022. a, b
Short summary
The Hunga Tonga–Hunga Ha‘apai volcanic eruption was one of the most vigorous volcanic explosions in the last centuries. The eruption launched many atmospheric waves traveling around the Earth. In this study, we identify these volcanic waves at the edge of space in the mesosphere/lower-thermosphere, leveraging wind observations conducted with multi-static meteor radars in northern Europe and with the Chilean Observation Network De Meteor Radars (CONDOR).
The Hunga Tonga–Hunga Ha‘apai volcanic eruption was one of the most vigorous volcanic...
