Articles | Volume 43, issue 2
https://doi.org/10.5194/angeo-43-427-2025
© Author(s) 2025. 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-43-427-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
TIMED Doppler Interferometer measurements of neutral winds at the mesosphere and lower thermosphere and comparison to meteor radar winds
Arthur Gauthier
CORRESPONDING AUTHOR
Institute of Applied Physics, University of Bern, Bern, Switzerland
Oeschger Center for Climate Change Research, University of Bern, Bern, Switzerland
Institute for Solar-Terrestrial Physics, German Aerospace Center (DLR), Neustrelitz, Germany
Claudia Borries
Institute for Solar-Terrestrial Physics, German Aerospace Center (DLR), Neustrelitz, Germany
Alexander Kozlovsky
Sodankylä Geophysical Observatory, University of Oulu, Oulu, Finland
Diego Janches
ITM Physics Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD, USA
Peter Brown
Dept. of Physics and Astronomy, University of Western Ontario, London, Ontario, Canada
Western Institute for Earth and Space Exploration, University of Western Ontario, London, Ontario, Canada
Denis Vida
Dept. of Physics and Astronomy, University of Western Ontario, London, Ontario, Canada
Christoph Jacobi
Institute for Meteorology, Leipzig University, Leipzig, Germany
Damian Murphy
Australian Antarctic Division, Kingston, Tasmania, Australia
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
Institute for Space-Earth Environmental Research, Nagoya University, Nagoya, Japan
Mark Lester
University of Leicester, Leicester, UK
Johan Kero
Swedish Institute of Space Physics (IRF), Kiruna, Sweden
Nicholas Mitchell
British Antarctic Survey, Cambridge, CB3 0ET, UK
Department of Electronic and Electrical Engineering, University of Bath, Bath, UK
Tracy Moffat-Griffin
British Antarctic Survey, Cambridge, CB3 0ET, UK
Institute of Applied Physics, University of Bern, Bern, Switzerland
Oeschger Center for Climate Change Research, University of Bern, Bern, Switzerland
Related authors
No articles found.
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
Short summary
Short summary
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.
Sina Mehrdad, Sajedeh Marjani, Dörthe Handorf, and Christoph Jacobi
EGUsphere, https://doi.org/10.5194/egusphere-2025-3612, https://doi.org/10.5194/egusphere-2025-3612, 2025
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
We studied how strong wind disturbances caused by mountains can disturb the polar vortex, a large pool of cold air high above the North Pole. Using simulations, we boosted these wind disturbances over the Himalayas, North America, and East Asia. We found they can shift, weaken, and mix the vortex in different ways depending on the region. This helps explain how mountains influence the upper atmosphere and improve forecasts of extreme cold weather at the surface.
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
EGUsphere, https://doi.org/10.5194/egusphere-2025-2827, https://doi.org/10.5194/egusphere-2025-2827, 2025
This preprint is open for discussion and under review for Annales Geophysicae (ANGEO).
Short summary
Short summary
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.
Gabriel Augusto Giongo, Cristiano Max Wrasse, Pierre-Dominique Pautet, José Valentin Bageston, Prosper Kwamla Nyassor, Cosme Alexandre Oliveira Barros Figueiredo, Anderson Vestena Bilibio, Tracy Moffat-Griffin, Damian John Murphy, Toyese Tunde Ayorinde, Delano Gobbi, and Hisao Takahashi
EGUsphere, https://doi.org/10.5194/egusphere-2025-3114, https://doi.org/10.5194/egusphere-2025-3114, 2025
This preprint is open for discussion and under review for Atmospheric Chemistry and Physics (ACP).
Short summary
Short summary
This work analyzes the medium-scale atmospheric gravity waves observed by ground-based airglow imaging over the Antarctic continent. Medium-scale gravity waves refer to waves larger than 50 km of horizontal wavelength, and have not been analyzed in that region so far. Wave parameters and horizontal propagation characteristics were obtained by a recently improved methodology and are described thoroughly.
Kian Sartipzadeh, Andreas Kvammen, Björn Gustavsson, Njål Gulbrandsen, Magnar Gullikstad Johnsen, Devin Huyghebaert, and Juha Vierinen
EGUsphere, https://doi.org/10.5194/egusphere-2025-3070, https://doi.org/10.5194/egusphere-2025-3070, 2025
Short summary
Short summary
Knowing charged particle densities high above Earth is key for forecasting space weather effects on satellites and communications, but they are difficult to estimate at high latitudes because of auroras. We built an artificial intelligence model for northern Norway using radar observations, magnetic field measurements, geophysical indices and solar activity. It produces more accurate estimates than existing methods, even during auroral events, and can be adapted to other regions.
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
Short summary
Short summary
The Earth’s magnetic field is not closed at high latitudes. Electrically charged particles can penetrate the Earth’s atmosphere, deposit their energy, and heat the local atmosphere–ionosphere. This presumably causes an upwelling of the neutral atmosphere, which affects the atmosphere–ionosphere coupling. We apply a new analysis technique to infer the atmospheric density from incoherent scatter radar measurements. We identify signs of particle precipitation impact on the neutral atmosphere.
Sina Mehrdad, Sajedeh Marjani, Dörthe Handorf, and Christoph Jacobi
EGUsphere, https://doi.org/10.5194/egusphere-2025-3005, https://doi.org/10.5194/egusphere-2025-3005, 2025
Short summary
Short summary
Wind flowing over mountains creates wave-like patterns aloft that can influence the atmosphere higher up in the stratosphere and mesosphere. In this study, we intensified these waves over specific regions like the Himalayas and Rocky Mountains and examined the resulting climate effects. We found that this can shift global wind patterns and even impact extreme events near the poles, showing how small regional changes in stratospheric wind patterns can influence the broader climate system.
Devin Huyghebaert, Juha Vierinen, Björn Gustavsson, Ralph Latteck, Toralf Renkwitz, Marius Zecha, Claudia C. Stephan, J. Federico Conte, Daniel Kastinen, Johan Kero, and Jorge L. Chau
EGUsphere, https://doi.org/10.5194/egusphere-2025-2323, https://doi.org/10.5194/egusphere-2025-2323, 2025
This preprint is open for discussion and under review for Atmospheric Measurement Techniques (AMT).
Short summary
Short summary
The phenomena of meteors occurs at altitudes of 60–120 km and can be used to measure the neutral atmosphere. We use a large high power radar system in Norway (MAARSY) to determine changes to the atmospheric density between the years of 2016–2023 at altitudes of 85–115 km. The same day-of-year is compared, minimizing changes to the measurements due to factors other than the atmosphere. This presents a novel method by which to obtain atmospheric neutral density variations.
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
Short summary
Short summary
Analysis of 10 years of continuous measurements provided MMARIA/SIMONe Norway and MMARIA/SIMONe Germany reveals that the divergent and vortical motions in the mesosphere and lower thermosphere exchange the dominant role depending on the height and the time of the year. At summer mesopause altitudes over middle latitudes, the horizontal divergence and the relative vorticity contribute approximately the same, indicating an energetic balance between mesoscale divergent and vortical motions.
Christoph Jacobi, Khalil Karami, Ales Kuchar, Manfred Ern, Toralf Renkwitz, Ralph Latteck, and Jorge L. Chau
Adv. Radio Sci., 23, 21–31, https://doi.org/10.5194/ars-23-21-2025, https://doi.org/10.5194/ars-23-21-2025, 2025
Short summary
Short summary
Half-hourly mean winds have been obtained using ground-based low-frequency and very high frequency radio observations of the mesopause region at Collm, Germany, since 1984. Long-term changes of wind variances, which are proxies for short-period atmospheric gravity waves, have been analysed. Gravity wave amplitudes increase with time in winter, but mainly decrease in summer. The trends are consistent with mean wind changes according to wave theory.
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
Short summary
Short summary
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
Short summary
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.
Maria Gloria Tan Jun Rios, Claudia Borries, Huixin Liu, and Jens Mielich
Ann. Geophys., 43, 73–89, https://doi.org/10.5194/angeo-43-73-2025, https://doi.org/10.5194/angeo-43-73-2025, 2025
Short summary
Short summary
This study analyzes changes in the ionospheric response to solar flux over five complete solar cycles (1957 to 2023). We use Juliusruh hourly data of the peak electron density of the F2 layer, NmF2, and three solar extreme ultraviolet (EUV) radiation proxies. The response is better represented by a cubic regression, and F30 shows the highest correlation for describing NmF2 dependence over time. These results reveal a decrease in NmF2 influenced by the intensity of the solar activity index.
Natalie Kaifler, Bernd Kaifler, Markus Rapp, Guiping Liu, Diego Janches, Gerd Baumgarten, and Jose-Luis Hormaechea
Atmos. Chem. Phys., 24, 14029–14044, https://doi.org/10.5194/acp-24-14029-2024, https://doi.org/10.5194/acp-24-14029-2024, 2024
Short summary
Short summary
Noctilucent clouds (NLCs) are silvery clouds that can be viewed during twilight and indicate atmospheric conditions like temperature and water vapor in the upper mesosphere. High-resolution measurements from a remote sensing laser instrument provide NLC height, brightness, and occurrence rate since 2017. Most observations occur in the morning hours, likely caused by strong tidal winds, and NLC ice particles are thus transported from elsewhere to the observing location in the Southern Hemisphere.
Sina Mehrdad, Dörthe Handorf, Ines Höschel, Khalil Karami, Johannes Quaas, Sudhakar Dipu, and Christoph Jacobi
Weather Clim. Dynam., 5, 1223–1268, https://doi.org/10.5194/wcd-5-1223-2024, https://doi.org/10.5194/wcd-5-1223-2024, 2024
Short summary
Short summary
This study introduces a novel deep learning (DL) approach to analyze how regional radiative forcing in Europe impacts the Arctic climate. By integrating atmospheric poleward energy transport with DL-based clustering of atmospheric patterns and attributing anomalies to specific clusters, our method reveals crucial, nuanced interactions within the climate system, enhancing our understanding of intricate climate dynamics.
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
Short summary
Short summary
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).
Ales Kuchar, Maurice Öhlert, Roland Eichinger, and Christoph Jacobi
Weather Clim. Dynam., 5, 895–912, https://doi.org/10.5194/wcd-5-895-2024, https://doi.org/10.5194/wcd-5-895-2024, 2024
Short summary
Short summary
Exploring the polar vortex's impact on climate, the study evaluates model simulations against the ERA5 reanalysis data. Revelations about model discrepancies in simulating disruptive stratospheric warmings and vortex behavior highlight the need for refined model simulations of past climate. By enhancing our understanding of these dynamics, the research contributes to more reliable climate projections of the polar vortex with the impact on surface climate.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Ralph Latteck and Damian J. Murphy
Ann. Geophys., 42, 55–68, https://doi.org/10.5194/angeo-42-55-2024, https://doi.org/10.5194/angeo-42-55-2024, 2024
Short summary
Short summary
This paper gives an overview of continuous measurements of polar mesophere summer echoes (PMSE) by VHF radars at Andøya (69° N) and Davis (69° S). PMSE signal strengths are of the same order of magnitude; significantly fewer PMSE were observed in the Southern than the Northern Hemisphere. Compared to Andøya, the PMSE season over Davis starts ~7 d later and ends 9 d earlier; PMSE occur less frequently but with greater seasonal/diurnal occurrence variability, reaching higher peak altitudes.
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
Short summary
Short summary
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.
Christoph Jacobi, Ales Kuchar, Toralf Renkwitz, and Juliana Jaen
Adv. Radio Sci., 21, 111–121, https://doi.org/10.5194/ars-21-111-2023, https://doi.org/10.5194/ars-21-111-2023, 2023
Short summary
Short summary
Middle atmosphere long-term changes show the signature of climate change. We analyse 43 years of mesopause region horizontal winds obtained at two sites in Germany. We observe mainly positive trends of the zonal prevailing wind throughout the year, while the meridional winds tend to decrease in magnitude in both summer and winter. Furthermore, there is a change in long-term trends around the late 1990s, which is most clearly visible in summer winds.
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
Short summary
Short summary
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
Short summary
Short summary
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.
Olivia Linke, Johannes Quaas, Finja Baumer, Sebastian Becker, Jan Chylik, Sandro Dahlke, André Ehrlich, Dörthe Handorf, Christoph Jacobi, Heike Kalesse-Los, Luca Lelli, Sina Mehrdad, Roel A. J. Neggers, Johannes Riebold, Pablo Saavedra Garfias, Niklas Schnierstein, Matthew D. Shupe, Chris Smith, Gunnar Spreen, Baptiste Verneuil, Kameswara S. Vinjamuri, Marco Vountas, and Manfred Wendisch
Atmos. Chem. Phys., 23, 9963–9992, https://doi.org/10.5194/acp-23-9963-2023, https://doi.org/10.5194/acp-23-9963-2023, 2023
Short summary
Short summary
Lapse rate feedback (LRF) is a major driver of the Arctic amplification (AA) of climate change. It arises because the warming is stronger at the surface than aloft. Several processes can affect the LRF in the Arctic, such as the omnipresent temperature inversion. Here, we compare multimodel climate simulations to Arctic-based observations from a large research consortium to broaden our understanding of these processes, find synergy among them, and constrain the Arctic LRF and AA.
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
Short summary
Short summary
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
Short summary
Short summary
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.
Gunter Stober, Alan Liu, Alexander Kozlovsky, Zishun Qiao, Witali Krochin, Guochun Shi, Johan Kero, Masaki Tsutsumi, Njål Gulbrandsen, Satonori Nozawa, Mark Lester, Kathrin Baumgarten, Evgenia Belova, and Nicholas Mitchell
Ann. Geophys., 41, 197–208, https://doi.org/10.5194/angeo-41-197-2023, https://doi.org/10.5194/angeo-41-197-2023, 2023
Short summary
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).
Khalil Karami, Rolando Garcia, Christoph Jacobi, Jadwiga H. Richter, and Simone Tilmes
Atmos. Chem. Phys., 23, 3799–3818, https://doi.org/10.5194/acp-23-3799-2023, https://doi.org/10.5194/acp-23-3799-2023, 2023
Short summary
Short summary
Alongside mitigation and adaptation efforts, stratospheric aerosol intervention (SAI) is increasingly considered a third pillar to combat dangerous climate change. We investigate the teleconnection between the quasi-biennial oscillation in the equatorial stratosphere and the Arctic stratospheric polar vortex under a warmer climate and an SAI scenario. We show that the Holton–Tan relationship weakens under both scenarios and discuss the physical mechanisms responsible for such changes.
Christoph Jacobi, Kanykei Kandieva, and Christina Arras
Adv. Radio Sci., 20, 85–92, https://doi.org/10.5194/ars-20-85-2023, https://doi.org/10.5194/ars-20-85-2023, 2023
Short summary
Short summary
Sporadic E (Es) layers are thin regions of accumulated ions in the lower ionosphere. They can be observed by disturbances of GNSS links between low-Earth orbiting satellites and GNSS satellites. Es layers are influenced by neutral atmospheric tides and show the coupling between the neutral atmosphere and the ionosphere. Here we analyse migrating (sun-synchronous) and non-migrating tidal components in Es. The main signatures are migrating Es, but nonmigrating components are found as well.
Gerhard Georg Bruno Schmidtke, Raimund Brunner, and Christoph Jacobi
EGUsphere, https://doi.org/10.5194/egusphere-2023-139, https://doi.org/10.5194/egusphere-2023-139, 2023
Preprint withdrawn
Short summary
Short summary
The instrument records annual changes in Spectral Outgoing Radiation from 200–1100 nm, with 60 photomultiplier tubes simultaneously providing spectrometer and photometer data. Using Total Solar Irradiance data with a stability of 0.01 Wm-2 per year to recalibrate the established instruments, stable data of ~0.1 Wm-2 over a solar cycle period is expected. Determination of the changes in the global green Earth coverage and mapping will also assess the impact of climate engineering actions.
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
Short summary
Short summary
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
Short summary
Short summary
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.
Neil P. Hindley, Nicholas J. Mitchell, Neil Cobbett, Anne K. Smith, Dave C. Fritts, Diego Janches, Corwin J. Wright, and Tracy Moffat-Griffin
Atmos. Chem. Phys., 22, 9435–9459, https://doi.org/10.5194/acp-22-9435-2022, https://doi.org/10.5194/acp-22-9435-2022, 2022
Short summary
Short summary
We present observations of winds in the mesosphere and lower thermosphere (MLT) from a recently installed meteor radar on the remote island of South Georgia (54° S, 36° W). We characterise mean winds, tides, planetary waves, and gravity waves in the MLT at this location and compare our measured winds with a leading climate model. We find that the observed wintertime winds are unexpectedly reversed from model predictions, probably because of missing impacts of secondary gravity waves in the model.
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
Short summary
Short summary
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.
Ales Kuchar, Petr Sacha, Roland Eichinger, Christoph Jacobi, Petr Pisoft, and Harald Rieder
EGUsphere, https://doi.org/10.5194/egusphere-2022-474, https://doi.org/10.5194/egusphere-2022-474, 2022
Preprint archived
Short summary
Short summary
We focus on the impact of small-scale orographic gravity waves (OGWs) above the Himalayas. The interaction of GWs with the large-scale circulation in the stratosphere is not still well understood and can have implications on climate projections. We use a chemistry-climate model to show that these strong OGW events are associated with anomalously increased upward planetary-scale waves and in turn affect the circumpolar circulation and have the potential to alter ozone variability as well.
Jill Brouwer, Alexander D. Fraser, Damian J. Murphy, Pat Wongpan, Alberto Alberello, Alison Kohout, Christopher Horvat, Simon Wotherspoon, Robert A. Massom, Jessica Cartwright, and Guy D. Williams
The Cryosphere, 16, 2325–2353, https://doi.org/10.5194/tc-16-2325-2022, https://doi.org/10.5194/tc-16-2325-2022, 2022
Short summary
Short summary
The marginal ice zone is the region where ocean waves interact with sea ice. Although this important region influences many sea ice, ocean and biological processes, it has been difficult to accurately measure on a large scale from satellite instruments. We present new techniques for measuring wave attenuation using the NASA ICESat-2 laser altimeter. By measuring how waves attenuate within the sea ice, we show that the marginal ice zone may be far wider than previously realised.
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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
Short summary
Short summary
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.
Dimitry Pokhotelov, Isabel Fernandez-Gomez, and Claudia Borries
Ann. Geophys., 39, 833–847, https://doi.org/10.5194/angeo-39-833-2021, https://doi.org/10.5194/angeo-39-833-2021, 2021
Short summary
Short summary
During geomagnetic storms, enhanced solar wind and changes in the interplanetary magnetic field lead to ionisation anomalies across the polar regions. The superstorm of 20 November 2003 was one of the largest events in recent history. Numerical simulations of ionospheric dynamics during the storm are compared with plasma observations to understand the mechanisms forming the polar plasma anomalies. The results are important for understanding and forecasting space weather in polar regions.
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
Short summary
Short summary
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
Short summary
Short summary
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.
Rajesh Vaishnav, Christoph Jacobi, Jens Berdermann, Mihail Codrescu, and Erik Schmölter
Ann. Geophys., 39, 641–655, https://doi.org/10.5194/angeo-39-641-2021, https://doi.org/10.5194/angeo-39-641-2021, 2021
Short summary
Short summary
We investigate the role of eddy diffusion in the delayed ionospheric response against solar flux changes in the solar rotation period using the CTIPe model. The study confirms that eddy diffusion is an important factor affecting the delay of the total electron content. An increase in eddy diffusion leads to faster transport processes and an increased loss rate, resulting in a decrease in the ionospheric delay.
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
Short summary
Short summary
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?
Matthew J. Griffith, Shaun M. Dempsey, David R. Jackson, Tracy Moffat-Griffin, and Nicholas J. Mitchell
Ann. Geophys., 39, 487–514, https://doi.org/10.5194/angeo-39-487-2021, https://doi.org/10.5194/angeo-39-487-2021, 2021
Short summary
Short summary
There is great scientific interest in extending atmospheric models upwards to include the upper atmosphere. The Met Office’s Unified Model has recently been successfully extended to include this region. Atmospheric tides are an important driver of atmospheric motion at these greater heights. This paper provides a first comparison of winds and tides produced by the new extended model with meteor radar observations, comparing key tidal properties and discussing their similarities and differences.
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
Short summary
Short summary
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.
Neil P. Hindley, Corwin J. Wright, Alan M. Gadian, Lars Hoffmann, John K. Hughes, David R. Jackson, John C. King, Nicholas J. Mitchell, Tracy Moffat-Griffin, Andrew C. Moss, Simon B. Vosper, and Andrew N. Ross
Atmos. Chem. Phys., 21, 7695–7722, https://doi.org/10.5194/acp-21-7695-2021, https://doi.org/10.5194/acp-21-7695-2021, 2021
Short summary
Short summary
One limitation of numerical atmospheric models is spatial resolution. For atmospheric gravity waves (GWs) generated over small mountainous islands, the driving effect of these waves on atmospheric circulations can be underestimated. Here we use a specialised high-resolution model over South Georgia island to compare simulated stratospheric GWs to colocated 3-D satellite observations. We find reasonable model agreement with observations, with some GW amplitudes much larger than expected.
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
Short summary
Short summary
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.
Rajesh Vaishnav, Erik Schmölter, Christoph Jacobi, Jens Berdermann, and Mihail Codrescu
Ann. Geophys., 39, 341–355, https://doi.org/10.5194/angeo-39-341-2021, https://doi.org/10.5194/angeo-39-341-2021, 2021
Short summary
Short summary
We investigate the delayed ionospheric response using the observed and CTIPe-model-simulated TEC against the solar EUV flux. The ionospheric delay estimated using model-simulated TEC is in good agreement with the delay estimated for observed TEC. The study confirms the model's capabilities to reproduce the delayed ionospheric response against the solar EUV flux. Results also indicate that the average delay is higher in the Northern Hemisphere as compared to the Southern Hemisphere.
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
Short summary
Short summary
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
Short summary
Short summary
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.
Andrew Orr, J. Scott Hosking, Aymeric Delon, Lars Hoffmann, Reinhold Spang, Tracy Moffat-Griffin, James Keeble, Nathan Luke Abraham, and Peter Braesicke
Atmos. Chem. Phys., 20, 12483–12497, https://doi.org/10.5194/acp-20-12483-2020, https://doi.org/10.5194/acp-20-12483-2020, 2020
Short summary
Short summary
Polar stratospheric clouds (PSCs) are clouds found in the Antarctic winter stratosphere and are implicated in the formation of the ozone hole. These clouds can sometimes be formed or enhanced by mountain waves, formed as air passes over hills or mountains. However, this important mechanism is missing in coarse-resolution climate models, limiting our ability to simulate ozone. This study examines an attempt to include the effects of mountain waves and their impact on PSCs and ozone.
Harikrishnan Charuvil Asokan, Jorge L. Chau, Raffaele Marino, Juha Vierinen, Fabio Vargas, Juan Miguel Urco, Matthias Clahsen, and Christoph Jacobi
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-974, https://doi.org/10.5194/acp-2020-974, 2020
Preprint withdrawn
Short summary
Short summary
This paper explores the dynamics of gravity waves and turbulence present in the mesosphere and lower thermosphere (MLT) region. We utilized two different techniques on meteor radar observations and simulations to obtain power spectra at different horizontal scales. The techniques are applied to a special campaign conducted in northern Germany in November 2018. The study revealed the dominance of large-scale structures with horizontal scales larger than 500 km during the campaign period.
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
Short summary
Short summary
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
Short summary
Short summary
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.
Ales Kuchar, Petr Sacha, Roland Eichinger, Christoph Jacobi, Petr Pisoft, and Harald E. Rieder
Weather Clim. Dynam., 1, 481–495, https://doi.org/10.5194/wcd-1-481-2020, https://doi.org/10.5194/wcd-1-481-2020, 2020
Short summary
Short summary
Our study focuses on the impact of topographic structures such as the Himalayas and Rocky Mountains, so-called orographic gravity-wave hotspots. These hotspots play an important role in the dynamics of the middle atmosphere, in particular in the lower stratosphere. We study intermittency and zonally asymmetric character of these hotspots and their effects on the upper stratosphere and mesosphere using a new detection method in various modeling and observational datasets.
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
Short summary
Short summary
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
Amante, C. and Eakins, B.: ETOPO1 1 Arc-Minute Global Relief Model: Procedures, Data Sources and Analysis, NOAA Technical Memorandum NESDIS NGDC-24, National Geophysical Data Center, NOAA, https://doi.org/10.7289/V5C8276M, 2009. a
Baumgarten, K. and Stober, G.: On the evaluation of the phase relation between temperature and wind tides based on ground-based measurements and reanalysis data in the middle atmosphere, Ann. Geophys., 37, 581–602, https://doi.org/10.5194/angeo-37-581-2019, 2019. a
Becker, E.: Dynamical Control of the Middle Atmosphere, Space Sci. Rev., 168, 283–314, https://doi.org/10.1007/s11214-011-9841-5, 2012. a
Becker, E.: Mean-Flow Effects of Thermal Tides in the Mesosphere and Lower Thermosphere, J. Atmos. Sci., 74, 2043–2063, https://doi.org/10.1175/JAS-D-16-0194.1, 2017. a
Brown, P., Wong, D., Weryk, R., and Wiegert, P.: A meteoroid stream survey using the Canadian Meteor Orbit Radar: II: Identification of minor showers using a 3D wavelet transform, Icarus, 207, 66–81, https://doi.org/10.1016/j.icarus.2009.11.015, 2010. a
Dhadly, M., Jones Jr., M., Emmert, J., Drob, D., Budzien, S., Zawdie, K., and McCormack, J.: Short-Term to Inter-Annual Variability of the Non-Migrating Tide DE3 From MIGHTI, SABER, and TIDI: Potential Tropospheric Sources and Ionospheric Impacts, J. Geophys. Res.-Space Phys., 129, e2024JA032849, https://doi.org/10.1029/2024JA032849, 2024. a
Dhadly, M. S., Englert, C. R., Drob, D. P., Emmert, J. T., Niciejewski, R., and Zawdie, K. A.: Comparison of ICON/MIGHTI and TIMED/TIDI neutral wind measurements in the lower thermosphere, J. Geophys. Res.-Space Phys., 126, e2021JA029904, https://doi.org/10.1029/2021JA029904, 2021. a, b, c
Fritts, D. C., Janches, D., Iimura, H., Hocking, W. K., Mitchell, N. J., Stockwell, R. G., Fuller, B., Vandepeer, B., Hormaechea, J., Brunini, C., and Levato, H.: Southern Argentina Agile Meteor Radar: System design and initial measurements of large-scale winds and tides, J. Geophys. Res.-Atmos., 115, D18112, https://doi.org/10.1029/2010JD013850, 2010. 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
Hagen, J., Murk, A., Rüfenacht, R., Khaykin, S., Hauchecorne, A., and Kämpfer, N.: WIRA-C: a compact 142-GHz-radiometer for continuous middle-atmospheric wind measurements, Atmos. Meas. Tech., 11, 5007–5024, https://doi.org/10.5194/amt-11-5007-2018, 2018. a
Hall, C. M. and Tsutsumi, M.: Changes in mesospheric dynamics at 78°N, 16°E and 70° N, 19° E: 2001–2012, J. Geophys. Res.-Atmos., 118, 2689–2701, 2013. a
Hindley, N. P., Mitchell, N. J., Cobbett, N., Smith, A. K., Fritts, D. C., Janches, D., Wright, C. J., and Moffat-Griffin, T.: Radar observations of winds, waves and tides in the mesosphere and lower thermosphere over South Georgia island (54° S, 36° W) and comparison with WACCM simulations, Atmos. Chem. Phys., 22, 9435–9459, https://doi.org/10.5194/acp-22-9435-2022, 2022. a, b
Hocking, W., Fuller, B., and Vandepeer, B.: Real-time determination of meteor-related parameters utilizing modern digital technology, J. Atmos. Sol.-Terr. Phy., 63, 155–169, https://doi.org/10.1016/S1364-6826(00)00138-3, 2001. a
Holdsworth, D. A., Reid, I. M., and Cervera, M. A.: Buckland Park all-sky interferometric meteor radar, Radio Sci., 39, rS5009, https://doi.org/10.1029/2003RS003014, 2004. a
Holdsworth, D. A., Murphy, D. J., Reid, I. M., and Morris, R. J.: Antarctic meteor observations using the Davis MST and meteor radars, Adv. Space Res., 42, 143–154, 2008. a
Jacobi, C., Fröhlich, K., Viehweg, C., Stober, G., and Kürschner, D.: Midlatitude mesosphere/lower thermosphere meridional winds and temperatures measured with meteor radar, Adv. Space Res., 39, 1278–1283, https://doi.org/10.1016/j.asr.2007.01.003, 2007. a
Lindzen, R. S.: Atmospheric Tides, Annu. Rev. Earth Planet. Sc., 7, 199–225, https://doi.org/10.1146/annurev.ea.07.050179.001215, 1979. a
Lindzen, R. S.: Turbulence and stress owing to gravity wave and tidal breakdown, J. Geophys. Res.-Oceans, 86, 9707–9714, https://doi.org/10.1029/JC086iC10p09707, 1981. a
Lindzen, R. S. and Chapman, S.: Atmospheric Tides, Space Sci. Rev., 10, 3–188, 1969. a
Liu, G., Janches, D., Ma, J., Lieberman, R. S., Stober, G., Moffat-Griffin, T., Mitchell, N. J., Kim, J.-H., Lee, C., and Murphy, D. J.: Mesosphere and Lower Thermosphere Winds and Tidal Variations During the 2019 Antarctic Sudden Stratospheric Warming, J. Geophys. Res.-Space Phys., 127, e2021JA030177, https://doi.org/10.1029/2021JA030177, 2022. a, b
Liu, H.-L.: Variability and predictability of the space environment as related to lower atmosphere forcing, Space Weather, 14, 634–658, https://doi.org/10.1002/2016SW001450, 2016. a
Matthias, V., Stober, G., Kozlovsky, A., Lester, M., Belova, E., and Kero, J.: Vertical Structure of the Arctic Spring Transition in the Middle Atmosphere, J. Geophys. Res.-Atmos., 126, e2020JD034353, https://doi.org/10.1029/2020JD034353, 2021. a
McCormack, J., Hoppel, K., Kuhl, D., de Wit, R., Stober, G., Espy, P., Baker, N., Brown, P., Fritts, D., Jacobi, C., Janches, D., Mitchell, N., Ruston, B., Swadley, S., Viner, K., Whitcomb, T., and Hibbins, R.: Comparison of mesospheric winds from a high-altitude meteorological analysis system and meteor radar observations during the boreal winters of 2009-2010 and 2012-2013, J. Atmos. Sol.-Terr. Phy., 154, 132–166, https://doi.org/10.1016/j.jastp.2016.12.007, 2017. a, b, c
Michigan Engineering: TIDI: Timed Doppler Interferometer, http://tidi.engin.umich.edu (last access: April 2024), 2025. a
Oberheide, J., Wu, Q., Ortland, D., Killeen, T., Hagan, M., Roble, R., Niciejewski, R., and Skinner, W.: Non-migrating diurnal tides as measured by the TIMED Doppler interferometer: Preliminary results, Adv. Space Res., 35, 1911–1917, https://doi.org/10.1016/j.asr.2005.01.063, 2005. a
Paulino, A. R., Rodrigues, D. O., Paulino, I., Lima, L. M., Buriti, R. A., Batista, P. P., Ridley, A., and Wu, C.: Comparison of meteor radar and satellite winds in the Brazilian equatorial region, Ann. Geophys., 43, 183–191, https://doi.org/10.5194/angeo-43-183-2025, 2025. a
Pokhotelov, D., Becker, E., Stober, G., and Chau, J. L.: Seasonal variability of atmospheric tides in the mesosphere and lower thermosphere: meteor radar data and simulations, Ann. Geophys., 36, 825–830, https://doi.org/10.5194/angeo-36-825-2018, 2018. a
Smith, A. K.: Global Dynamics of the MLT, Surv. Geophys., 33, 1177–1230, https://doi.org/10.1007/s10712-012-9196-9, 2012. a
Stober, G., Chau, J. L., Vierinen, J., Jacobi, C., and Wilhelm, S.: Retrieving horizontally resolved wind fields using multi-static meteor radar observations, Atmos. Meas. Tech., 11, 4891–4907, https://doi.org/10.5194/amt-11-4891-2018, 2018. a
Stober, G., Baumgarten, K., McCormack, J. P., Brown, P., and Czarnecki, J.: Comparative study between ground-based observations and NAVGEM-HA analysis data in the mesosphere and lower thermosphere region, Atmos. Chem. Phys., 20, 11979–12010, https://doi.org/10.5194/acp-20-11979-2020, 2020. a, b, c, d
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, 2021a. a, b
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, b, c, d
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
Stober, G., Vadas, S. L., Becker, E., Liu, A., Kozlovsky, A., Janches, D., Qiao, Z., Krochin, W., Shi, G., Yi, W., Zeng, J., Brown, P., Vida, D., Hindley, N., Jacobi, C., Murphy, D., Buriti, R., Andrioli, V., Batista, P., Marino, J., Palo, S., Thorsen, D., Tsutsumi, M., Gulbrandsen, N., Nozawa, S., Lester, M., Baumgarten, K., Kero, J., Belova, E., Mitchell, N., Moffat-Griffin, T., and Li, N.: Gravity waves generated by the Hunga Tonga–Hunga Ha′apai volcanic eruption and their global propagation in the mesosphere/lower thermosphere observed by meteor radars and modeled with the High-Altitude general Mechanistic Circulation Model, Atmos. Chem. Phys., 24, 4851–4873, https://doi.org/10.5194/acp-24-4851-2024, 2024. a
van Caspel, W. E., Espy, P., Hibbins, R., Stober, G., Brown, P., Jacobi, C., and Kero, J.: A Case Study of the Solar and Lunar Semidiurnal Tide Response to the 2013 Sudden Stratospheric Warming, J. Geophys. Res.-Space Phys., 128, e2023JA031680, https://doi.org/10.1029/2023JA031680, 2023. a
Webster, A. R., Brown, P. G., Jones, J., Ellis, K. J., and Campbell-Brown, M.: Canadian Meteor Orbit Radar (CMOR), Atmos. Chem. Phys., 4, 679–684, https://doi.org/10.5194/acp-4-679-2004, 2004. a
Wilhelm, S., Stober, G., and Chau, J. L.: A comparison of 11-year mesospheric and lower thermospheric winds determined by meteor and MF radar at 69° N, Ann. Geophys., 35, 893–906, https://doi.org/10.5194/angeo-35-893-2017, 2017. a
Wu, C. and Ridley, A. J.: Comparison of TIDI Line of Sight Winds With ICON-MIGHTI Measurements, J. Geophys. Res.-Space Phys., 128, e2022JA030910, https://doi.org/10.1029/2022JA030910, 2023. a
Wu, Q., Killeen, T., Ortland, D., Solomon, S., Gablehouse, R., Johnson, R., Skinner, W., Niciejewski, R., and Franke, S.: TIMED Doppler interferometer (TIDI) observations of migrating diurnal and semidiurnal tides, J. Atmos. Sol.-Terr. Phy., 68, 408–417, https://doi.org/10.1016/j.jastp.2005.02.031, 2006. a
Short summary
This study focuses on a TIMED Doppler Interferometer (TIDI)–meteor radar (MR) comparison of zonal and meridional winds and their dependence on local time and latitude. The correlation calculation between TIDI wind measurements and MR winds shows good agreement. A TIDI–MR seasonal comparison and analysis of the altitude–latitude dependence for winds are performed. TIDI reproduces the mean circulation well when compared with MRs and may be a useful lower boundary for general circulation models.
This study focuses on a TIMED Doppler Interferometer (TIDI)–meteor radar (MR) comparison of...