Articles | Volume 37, issue 3
Ann. Geophys., 37, 273–288, 2019
https://doi.org/10.5194/angeo-37-273-2019
© Author(s) 2019. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue: Vertical coupling in the atmosphere–ionosphere system
Regular paper 06 May 2019
Regular paper | 06 May 2019
Quarterdiurnal signature in sporadic E occurrence rates and comparison with neutral wind shear
Christoph Jacobi et al.
Related authors
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.
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, and Johan Kero
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-142, https://doi.org/10.5194/acp-2021-142, 2021
Preprint under review for ACP
Rajesh Vaishnav, Christoph Jacobi, Jens Berdermann, Mihail Codrescu, and Erik Schmölter
Ann. Geophys. Discuss., https://doi.org/10.5194/angeo-2021-12, https://doi.org/10.5194/angeo-2021-12, 2021
Revised manuscript under review for ANGEO
Short summary
Short summary
We investigate the role of eddy diffusion on the delayed ionospheric response against solar flux changes at the solar rotation period using the CTIPe model. The study confirms that eddy diffusion is a primary factor that influences the delay of the total electron content. An increase in the eddy diffusion leads to faster transport processes and an increased loss rates resulting in a decrease of the ionospheric delay.
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
Revised manuscript under review for ACP
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.
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.
Christoph Geißler, Christoph Jacobi, and Friederike Lilienthal
Ann. Geophys., 38, 527–544, https://doi.org/10.5194/angeo-38-527-2020, https://doi.org/10.5194/angeo-38-527-2020, 2020
Short summary
Short summary
This is an extensive model study to analyze the migrating quarterdiurnal solar tide (QDT) and its forcing mechanisms in the middle atmosphere. We first show a climatology of the QDT amplitudes and examine the contribution of the different forcing mechanisms, including direct solar, nonlinear and gravity wave forcing, on the QDT amplitude. We then investigate the destructive interference between the individual forcing mechanisms.
Friederike Lilienthal, Erdal Yiğit, Nadja Samtleben, and Christoph Jacobi
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2019-339, https://doi.org/10.5194/gmd-2019-339, 2020
Preprint withdrawn
Short summary
Short summary
Gravity waves are a small-scale but prominent dynamical feature in the Earth's atmosphere. Here, we use a mechanistic nonlinear general circulation model and implement a modern whole atmosphere gravity wave parameterization. We study the response of the atmosphere on several phase speed spectra. We find a large influence of fast travelling waves on the background dynamics in the thermosphere and also a strong dependence of the amplitude of the terdiurnal solar tide, indicating wave interactions.
Erik Schmölter, Jens Berdermann, Norbert Jakowski, and Christoph Jacobi
Ann. Geophys., 38, 149–162, https://doi.org/10.5194/angeo-38-149-2020, https://doi.org/10.5194/angeo-38-149-2020, 2020
Short summary
Short summary
This study correlates ionospheric parameters with the integrated solar radiation for an analysis of the delayed ionospheric response in order to confirm previous studies on the delay and to further specify variations of the delay (seasonal and spatial). Results also indicate the dependence on the geomagnetic activity as well as on the 11-year solar cycle. The results are important for the understanding of ionospheric processes and could be used for the validation of ionospheric models.
Nadja Samtleben, Aleš Kuchař, Petr Šácha, Petr Pišoft, and Christoph Jacobi
Ann. Geophys., 38, 95–108, https://doi.org/10.5194/angeo-38-95-2020, https://doi.org/10.5194/angeo-38-95-2020, 2020
Short summary
Short summary
The additional transfer of momentum and energy induced by locally breaking gravity wave hotspots in the lower stratosphere may lead to a destabilization of the polar vortex, which is strongly dependent on the position of the hotspot. The simulations with a global circulation model show that hotspots located above Eurasia cause a total decrease in the stationary planetary wave (SPW) activity, while the impact of hotspots located in North America mostly increase the SPW activity.
Rajesh Vaishnav, Christoph Jacobi, and Jens Berdermann
Ann. Geophys., 37, 1141–1159, https://doi.org/10.5194/angeo-37-1141-2019, https://doi.org/10.5194/angeo-37-1141-2019, 2019
Short summary
Short summary
We investigate the ionospheric response to the temporal and spatial dynamics of the solar activity using total electron content (TEC) maps and multiple solar proxies. The maximum correlation at a 16–32-d timescale is observed between the He-II, Mg-II, and F30 with respect to global mean TEC, with an effective time delay of about 1 d. The most suitable proxy to represent the solar activity at the timescales of 16–32 d and 32–64 d is He-II.
Friederike Lilienthal and Christoph Jacobi
Ann. Geophys., 37, 943–953, https://doi.org/10.5194/angeo-37-943-2019, https://doi.org/10.5194/angeo-37-943-2019, 2019
Short summary
Short summary
We analyzed the forcing mechanisms of the migrating terdiurnal solar tide in the middle atmosphere, focusing the impact on the zonal mean circulation. We show that the primary solar forcing is the most dominant one but secondary wave–wave interactions also contribute in the lower thermosphere region. We further demonstrate that small-scale gravity waves can strongly and irregularly influence the amplitude of the terdiurnal tide as well as the background circulation in the thermosphere.
Christoph Jacobi and Christina Arras
Adv. Radio Sci., 17, 213–224, https://doi.org/10.5194/ars-17-213-2019, https://doi.org/10.5194/ars-17-213-2019, 2019
Short summary
Short summary
We analyze tidal phases and related wind shear in the mesosphere and
lower thermosphere as observed by a meteor radar. The wind shear phases are compared with those of sporadic E occurrence rates, which were derived from GPS radio occultation observations. We find good correspondence between radar derived wind shear and sporadic E phases for the semidiurnal, terdiurnal, and quarterdiurnal tidal components, but not for the diurnal tide.
Nadja Samtleben, Christoph Jacobi, Petr Pišoft, Petr Šácha, and Aleš Kuchař
Ann. Geophys., 37, 507–523, https://doi.org/10.5194/angeo-37-507-2019, https://doi.org/10.5194/angeo-37-507-2019, 2019
Short summary
Short summary
Simulations of locally breaking gravity wave hot spots in the stratosphere show a suppression of wave propagation at midlatitudes, which is partly compensated for by additional wave propagation through the polar region. This leads to a displacement of the polar vortex towards lower latitudes. The effect is highly dependent on the position of the artificial gravity wave forcing. It is strongest (weakest) for hot spots at lower to middle latitudes (higher latitudes).
Daniel Mewes and Christoph Jacobi
Atmos. Chem. Phys., 19, 3927–3937, https://doi.org/10.5194/acp-19-3927-2019, https://doi.org/10.5194/acp-19-3927-2019, 2019
Short summary
Short summary
Horizontal moist static energy (MSE) transport patterns were extracted from reanalysis data using an artificial neuronal network for the winter months. The results show that during the last 30 years transport pathways that favour MSE transport through the North Atlantic are getting more frequent. This North Atlantic pathway is connected to positive temperature anomalies over the central Arctic, which implies a connection between Arctic amplification and the change in horizontal heat transport.
Sven Wilhelm, Gunter Stober, Vivien Matthias, Christoph Jacobi, and Damian J. Murphy
Ann. Geophys., 37, 1–14, https://doi.org/10.5194/angeo-37-1-2019, https://doi.org/10.5194/angeo-37-1-2019, 2019
Short summary
Short summary
This study shows that the mesospheric winds are affected by an expansion–shrinking of the mesosphere and lower thermosphere that takes place due to changes in the intensity of the solar radiation, which affects the density within the atmosphere. On seasonal timescales, an increase in the neutral density occurs together with a decrease in the eastward-directed zonal wind. Further, even after removing the seasonal and the 11-year solar cycle variations, we show a connection between them.
Friederike Lilienthal, Christoph Jacobi, and Christoph Geißler
Atmos. Chem. Phys., 18, 15725–15742, https://doi.org/10.5194/acp-18-15725-2018, https://doi.org/10.5194/acp-18-15725-2018, 2018
Short summary
Short summary
The terdiurnal solar tide is an atmospheric wave, owing to the daily variation of solar heating with a period of 8 h. Here, we present model simulations of this tide and investigate the relative importance of possible forcing mechanisms because they are still under debate. These are, besides direct solar heating, nonlinear interactions between other tides and gravity wave–tide interactions. As a result, solar heating is most important and nonlinear effects partly counteract this forcing.
Christoph Jacobi, Christoph Geißler, Friederike Lilienthal, and Amelie Krug
Adv. Radio Sci., 16, 141–147, https://doi.org/10.5194/ars-16-141-2018, https://doi.org/10.5194/ars-16-141-2018, 2018
Short summary
Short summary
The possible sources of the quarterdiurnal tide (QDT) in the middle atmosphere are still under discussion. Therefore, meteor radar winds were analyzed with respect to non-linear interaction, which probably plays a role in winter, but to a lesser degree in summer. Numerical model experiments lead to the conclusion that, although non-linear tidal interaction is indeed one source of the QDT, the major source is direct solar forcing of the 6-hr tidal components.
Erik Schmölter, Jens Berdermann, Norbert Jakowski, Christoph Jacobi, and Rajesh Vaishnav
Adv. Radio Sci., 16, 149–155, https://doi.org/10.5194/ars-16-149-2018, https://doi.org/10.5194/ars-16-149-2018, 2018
Short summary
Short summary
Physical and chemical processes in the ionosphere are driven by complex interactions with the solar radiation. The ionospheric plasma is in particular sensitive to solar variations with a time delay between one and two days.
Here we present preliminary results of the ionospheric delay based on a comprehensive and reliable database consisting of GNSS TEC Maps and EUV spectral flux data.
Rajesh Vaishnav, Christoph Jacobi, Jens Berdermann, Erik Schmölter, and Mihail Codrescu
Adv. Radio Sci., 16, 157–165, https://doi.org/10.5194/ars-16-157-2018, https://doi.org/10.5194/ars-16-157-2018, 2018
Short summary
Short summary
We investigate the ionospheric response to solar Extreme Ultraviolet (EUV) variations using different solar proxies and IGS TEC maps. An ionospheric delay in GTEC is observed at the 27 days solar rotation period with the time scale of about ~ 1–2 days. Here we present preliminary results from the CTIPe model simulations which qualitatively reproduce the observed ~1-2 days delay in GTEC, which is might be due to vertical transport processes.
Gunter Stober, Jorge L. Chau, Juha Vierinen, Christoph Jacobi, and Sven Wilhelm
Atmos. Meas. Tech., 11, 4891–4907, https://doi.org/10.5194/amt-11-4891-2018, https://doi.org/10.5194/amt-11-4891-2018, 2018
Sabine Wüst, Thomas Offenwanger, Carsten Schmidt, Michael Bittner, Christoph Jacobi, Gunter Stober, Jeng-Hwa Yee, Martin G. Mlynczak, and James M. Russell III
Atmos. Meas. Tech., 11, 2937–2947, https://doi.org/10.5194/amt-11-2937-2018, https://doi.org/10.5194/amt-11-2937-2018, 2018
Short summary
Short summary
OH*-spectrometer measurements allow the analysis of gravity wave ground-based periods, but spatial information cannot necessarily be deduced. We combine the approach of Wachter at al. (2015) in order to derive horizontal wavelengths (but based on only one OH* spectrometer) with additional information about wind and temperature and compute vertical wavelengths. Knowledge of these parameters is a precondition for the calculation of further information such as the wave group velocity.
Christoph Jacobi, Tatiana Ermakova, Daniel Mewes, and Alexander I. Pogoreltsev
Adv. Radio Sci., 15, 199–206, https://doi.org/10.5194/ars-15-199-2017, https://doi.org/10.5194/ars-15-199-2017, 2017
Short summary
Short summary
There is continuous interest in coupling processes between the lower and middle atmosphere. Here we analyse midlatitude winds measured by radar at 82–97 km and find that especially in February they are positively correlated with El Niño. The signal is strong for the upper altitudes accessible to the radar, but weakens below. The observations can be qualitatively reproduced by numerical experiments using a mechanistic global circulation model.
Friederike Lilienthal, Christoph Jacobi, Torsten Schmidt, Alejandro de la Torre, and Peter Alexander
Ann. Geophys., 35, 785–798, https://doi.org/10.5194/angeo-35-785-2017, https://doi.org/10.5194/angeo-35-785-2017, 2017
Short summary
Short summary
Gravity waves (GWs) are one of the most important dynamical features of the middle atmosphere that extends from the tropopause to the lower thermosphere. They originate from the troposphere and propagate upward. Here, we show the impact of the horizontal GW distribution in the lower atmosphere on the dynamics of the middle atmosphere using a global circulation model. As a result, we find that non-zonal GW structures can force additional stationary planetary waves.
Gunter Stober, Vivien Matthias, Christoph Jacobi, Sven Wilhelm, Josef Höffner, and Jorge L. Chau
Ann. Geophys., 35, 711–720, https://doi.org/10.5194/angeo-35-711-2017, https://doi.org/10.5194/angeo-35-711-2017, 2017
Petr Šácha, Friederike Lilienthal, Christoph Jacobi, and Petr Pišoft
Atmos. Chem. Phys., 16, 15755–15775, https://doi.org/10.5194/acp-16-15755-2016, https://doi.org/10.5194/acp-16-15755-2016, 2016
Short summary
Short summary
With a mechanistic model for the middle and upper atmosphere we performed sensitivity simulations to study a possible impact of a localized GW breaking hotspot in the eastern Asia–northern Pacific region and also the possible influence of the spatial distribution of gravity wave activity on the middle atmospheric circulation and transport. We show implications for polar vortex stability, in situ PW generation and longitudinal variability and strength of the Brewer–Dobson circulation.
Ch. Jacobi, N. Samtleben, and G. Stober
Adv. Radio Sci., 14, 169–174, https://doi.org/10.5194/ars-14-169-2016, https://doi.org/10.5194/ars-14-169-2016, 2016
Short summary
Short summary
VHF meteor radar observations of mesosphere/lower thermosphere daily temperatures have been performed at Collm, Germany. The data have been analyzed with respect to long-period oscillations at time scales of 2 to 30 days. The results reveal that oscillations with periods of up to 6 days are more frequently observed during summer, while those with longer periods have larger amplitudes during winter. The results are comparable with analyses from radar wind measurements.
Christoph Jacobi, Norbert Jakowski, Gerhard Schmidtke, and Thomas N. Woods
Adv. Radio Sci., 14, 175–180, https://doi.org/10.5194/ars-14-175-2016, https://doi.org/10.5194/ars-14-175-2016, 2016
Short summary
Short summary
The ionospheric response to solar extreme ultraviolet variability is shown by simple proxies based on Solar Dynamics Observatory/Extreme Ultraviolet Variability Experiment solar spectra. The daily proxies are compared with global mean total electron content. At time scales of the solar rotation up to about 40 days there is a time lag between EUV and TEC variability of about one day, with a tendency to increase for longer time scales.
P. Šácha, A. Kuchař, C. Jacobi, and P. Pišoft
Atmos. Chem. Phys., 15, 13097–13112, https://doi.org/10.5194/acp-15-13097-2015, https://doi.org/10.5194/acp-15-13097-2015, 2015
Short summary
Short summary
In this study, we present a discovery of an internal gravity wave activity and breaking hotspot collocated with an area of anomalously low annual cycle amplitude and specific dynamics in the stratosphere over the Northeastern Pacific/Eastern Asia coastal region. The reasons why this particular IGW activity hotspot was not discovered before nor the specific dynamics of this region pointed out are discussed together with possible consequences on the middle atmospheric dynamics and transport.
F. Lilienthal and Ch. Jacobi
Atmos. Chem. Phys., 15, 9917–9927, https://doi.org/10.5194/acp-15-9917-2015, https://doi.org/10.5194/acp-15-9917-2015, 2015
Short summary
Short summary
The quasi 2-day wave (QTDW), one of the most striking features in the mesosphere/lower thermosphere, is analyzed using meteor radar measurements at Collm (51°N, 13°E) during 2004-2014. The QTDW has periods lasting between 43 and 52h during strong summer bursts, and weaker enhancements are found during winter. A correlation between QTDW amplitudes and wind shear suggests baroclinic instability to be a likely forcing mechanism.
G. Schmidtke, Ch. Jacobi, B. Nikutowski, and Ch. Erhardt
Adv. Radio Sci., 12, 251–260, https://doi.org/10.5194/ars-12-251-2014, https://doi.org/10.5194/ars-12-251-2014, 2014
Ch. Jacobi
Adv. Radio Sci., 12, 161–165, https://doi.org/10.5194/ars-12-161-2014, https://doi.org/10.5194/ars-12-161-2014, 2014
F. Lilienthal and Ch. Jacobi
Adv. Radio Sci., 12, 205–210, https://doi.org/10.5194/ars-12-205-2014, https://doi.org/10.5194/ars-12-205-2014, 2014
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.
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, and Johan Kero
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2021-142, https://doi.org/10.5194/acp-2021-142, 2021
Preprint under review for ACP
Rajesh Vaishnav, Christoph Jacobi, Jens Berdermann, Mihail Codrescu, and Erik Schmölter
Ann. Geophys. Discuss., https://doi.org/10.5194/angeo-2021-12, https://doi.org/10.5194/angeo-2021-12, 2021
Revised manuscript under review for ANGEO
Short summary
Short summary
We investigate the role of eddy diffusion on the delayed ionospheric response against solar flux changes at the solar rotation period using the CTIPe model. The study confirms that eddy diffusion is a primary factor that influences the delay of the total electron content. An increase in the eddy diffusion leads to faster transport processes and an increased loss rates resulting in a decrease of the ionospheric delay.
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
Revised manuscript under review for ACP
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.
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.
Ankur Kepkar, Christina Arras, Jens Wickert, Harald Schuh, Mahdi Alizadeh, and Lung-Chih Tsai
Ann. Geophys., 38, 611–623, https://doi.org/10.5194/angeo-38-611-2020, https://doi.org/10.5194/angeo-38-611-2020, 2020
Short summary
Short summary
The paper focuses on the analyses of the global occurrence of equatorial plasma bubble events using S4 data that were calculated from GPS radio occultation measurements of the FormoSat-3/COSMIC mission. The advantage in using radio occultation data is that we get information not only on the occurrence and intensity of the equatorial bubble events, but also on the altitude distribution. We analyzed a 10.5-year time series of COSMIC data and demonstrated a strong dependence on the solar cycle.
Christoph Geißler, Christoph Jacobi, and Friederike Lilienthal
Ann. Geophys., 38, 527–544, https://doi.org/10.5194/angeo-38-527-2020, https://doi.org/10.5194/angeo-38-527-2020, 2020
Short summary
Short summary
This is an extensive model study to analyze the migrating quarterdiurnal solar tide (QDT) and its forcing mechanisms in the middle atmosphere. We first show a climatology of the QDT amplitudes and examine the contribution of the different forcing mechanisms, including direct solar, nonlinear and gravity wave forcing, on the QDT amplitude. We then investigate the destructive interference between the individual forcing mechanisms.
Friederike Lilienthal, Erdal Yiğit, Nadja Samtleben, and Christoph Jacobi
Geosci. Model Dev. Discuss., https://doi.org/10.5194/gmd-2019-339, https://doi.org/10.5194/gmd-2019-339, 2020
Preprint withdrawn
Short summary
Short summary
Gravity waves are a small-scale but prominent dynamical feature in the Earth's atmosphere. Here, we use a mechanistic nonlinear general circulation model and implement a modern whole atmosphere gravity wave parameterization. We study the response of the atmosphere on several phase speed spectra. We find a large influence of fast travelling waves on the background dynamics in the thermosphere and also a strong dependence of the amplitude of the terdiurnal solar tide, indicating wave interactions.
Erik Schmölter, Jens Berdermann, Norbert Jakowski, and Christoph Jacobi
Ann. Geophys., 38, 149–162, https://doi.org/10.5194/angeo-38-149-2020, https://doi.org/10.5194/angeo-38-149-2020, 2020
Short summary
Short summary
This study correlates ionospheric parameters with the integrated solar radiation for an analysis of the delayed ionospheric response in order to confirm previous studies on the delay and to further specify variations of the delay (seasonal and spatial). Results also indicate the dependence on the geomagnetic activity as well as on the 11-year solar cycle. The results are important for the understanding of ionospheric processes and could be used for the validation of ionospheric models.
Nadja Samtleben, Aleš Kuchař, Petr Šácha, Petr Pišoft, and Christoph Jacobi
Ann. Geophys., 38, 95–108, https://doi.org/10.5194/angeo-38-95-2020, https://doi.org/10.5194/angeo-38-95-2020, 2020
Short summary
Short summary
The additional transfer of momentum and energy induced by locally breaking gravity wave hotspots in the lower stratosphere may lead to a destabilization of the polar vortex, which is strongly dependent on the position of the hotspot. The simulations with a global circulation model show that hotspots located above Eurasia cause a total decrease in the stationary planetary wave (SPW) activity, while the impact of hotspots located in North America mostly increase the SPW activity.
Rajesh Vaishnav, Christoph Jacobi, and Jens Berdermann
Ann. Geophys., 37, 1141–1159, https://doi.org/10.5194/angeo-37-1141-2019, https://doi.org/10.5194/angeo-37-1141-2019, 2019
Short summary
Short summary
We investigate the ionospheric response to the temporal and spatial dynamics of the solar activity using total electron content (TEC) maps and multiple solar proxies. The maximum correlation at a 16–32-d timescale is observed between the He-II, Mg-II, and F30 with respect to global mean TEC, with an effective time delay of about 1 d. The most suitable proxy to represent the solar activity at the timescales of 16–32 d and 32–64 d is He-II.
Friederike Lilienthal and Christoph Jacobi
Ann. Geophys., 37, 943–953, https://doi.org/10.5194/angeo-37-943-2019, https://doi.org/10.5194/angeo-37-943-2019, 2019
Short summary
Short summary
We analyzed the forcing mechanisms of the migrating terdiurnal solar tide in the middle atmosphere, focusing the impact on the zonal mean circulation. We show that the primary solar forcing is the most dominant one but secondary wave–wave interactions also contribute in the lower thermosphere region. We further demonstrate that small-scale gravity waves can strongly and irregularly influence the amplitude of the terdiurnal tide as well as the background circulation in the thermosphere.
Christoph Jacobi and Christina Arras
Adv. Radio Sci., 17, 213–224, https://doi.org/10.5194/ars-17-213-2019, https://doi.org/10.5194/ars-17-213-2019, 2019
Short summary
Short summary
We analyze tidal phases and related wind shear in the mesosphere and
lower thermosphere as observed by a meteor radar. The wind shear phases are compared with those of sporadic E occurrence rates, which were derived from GPS radio occultation observations. We find good correspondence between radar derived wind shear and sporadic E phases for the semidiurnal, terdiurnal, and quarterdiurnal tidal components, but not for the diurnal tide.
Nadja Samtleben, Christoph Jacobi, Petr Pišoft, Petr Šácha, and Aleš Kuchař
Ann. Geophys., 37, 507–523, https://doi.org/10.5194/angeo-37-507-2019, https://doi.org/10.5194/angeo-37-507-2019, 2019
Short summary
Short summary
Simulations of locally breaking gravity wave hot spots in the stratosphere show a suppression of wave propagation at midlatitudes, which is partly compensated for by additional wave propagation through the polar region. This leads to a displacement of the polar vortex towards lower latitudes. The effect is highly dependent on the position of the artificial gravity wave forcing. It is strongest (weakest) for hot spots at lower to middle latitudes (higher latitudes).
Daniel Mewes and Christoph Jacobi
Atmos. Chem. Phys., 19, 3927–3937, https://doi.org/10.5194/acp-19-3927-2019, https://doi.org/10.5194/acp-19-3927-2019, 2019
Short summary
Short summary
Horizontal moist static energy (MSE) transport patterns were extracted from reanalysis data using an artificial neuronal network for the winter months. The results show that during the last 30 years transport pathways that favour MSE transport through the North Atlantic are getting more frequent. This North Atlantic pathway is connected to positive temperature anomalies over the central Arctic, which implies a connection between Arctic amplification and the change in horizontal heat transport.
Sven Wilhelm, Gunter Stober, Vivien Matthias, Christoph Jacobi, and Damian J. Murphy
Ann. Geophys., 37, 1–14, https://doi.org/10.5194/angeo-37-1-2019, https://doi.org/10.5194/angeo-37-1-2019, 2019
Short summary
Short summary
This study shows that the mesospheric winds are affected by an expansion–shrinking of the mesosphere and lower thermosphere that takes place due to changes in the intensity of the solar radiation, which affects the density within the atmosphere. On seasonal timescales, an increase in the neutral density occurs together with a decrease in the eastward-directed zonal wind. Further, even after removing the seasonal and the 11-year solar cycle variations, we show a connection between them.
Friederike Lilienthal, Christoph Jacobi, and Christoph Geißler
Atmos. Chem. Phys., 18, 15725–15742, https://doi.org/10.5194/acp-18-15725-2018, https://doi.org/10.5194/acp-18-15725-2018, 2018
Short summary
Short summary
The terdiurnal solar tide is an atmospheric wave, owing to the daily variation of solar heating with a period of 8 h. Here, we present model simulations of this tide and investigate the relative importance of possible forcing mechanisms because they are still under debate. These are, besides direct solar heating, nonlinear interactions between other tides and gravity wave–tide interactions. As a result, solar heating is most important and nonlinear effects partly counteract this forcing.
Christoph Jacobi, Christoph Geißler, Friederike Lilienthal, and Amelie Krug
Adv. Radio Sci., 16, 141–147, https://doi.org/10.5194/ars-16-141-2018, https://doi.org/10.5194/ars-16-141-2018, 2018
Short summary
Short summary
The possible sources of the quarterdiurnal tide (QDT) in the middle atmosphere are still under discussion. Therefore, meteor radar winds were analyzed with respect to non-linear interaction, which probably plays a role in winter, but to a lesser degree in summer. Numerical model experiments lead to the conclusion that, although non-linear tidal interaction is indeed one source of the QDT, the major source is direct solar forcing of the 6-hr tidal components.
Erik Schmölter, Jens Berdermann, Norbert Jakowski, Christoph Jacobi, and Rajesh Vaishnav
Adv. Radio Sci., 16, 149–155, https://doi.org/10.5194/ars-16-149-2018, https://doi.org/10.5194/ars-16-149-2018, 2018
Short summary
Short summary
Physical and chemical processes in the ionosphere are driven by complex interactions with the solar radiation. The ionospheric plasma is in particular sensitive to solar variations with a time delay between one and two days.
Here we present preliminary results of the ionospheric delay based on a comprehensive and reliable database consisting of GNSS TEC Maps and EUV spectral flux data.
Rajesh Vaishnav, Christoph Jacobi, Jens Berdermann, Erik Schmölter, and Mihail Codrescu
Adv. Radio Sci., 16, 157–165, https://doi.org/10.5194/ars-16-157-2018, https://doi.org/10.5194/ars-16-157-2018, 2018
Short summary
Short summary
We investigate the ionospheric response to solar Extreme Ultraviolet (EUV) variations using different solar proxies and IGS TEC maps. An ionospheric delay in GTEC is observed at the 27 days solar rotation period with the time scale of about ~ 1–2 days. Here we present preliminary results from the CTIPe model simulations which qualitatively reproduce the observed ~1-2 days delay in GTEC, which is might be due to vertical transport processes.
Gunter Stober, Jorge L. Chau, Juha Vierinen, Christoph Jacobi, and Sven Wilhelm
Atmos. Meas. Tech., 11, 4891–4907, https://doi.org/10.5194/amt-11-4891-2018, https://doi.org/10.5194/amt-11-4891-2018, 2018
Sabine Wüst, Thomas Offenwanger, Carsten Schmidt, Michael Bittner, Christoph Jacobi, Gunter Stober, Jeng-Hwa Yee, Martin G. Mlynczak, and James M. Russell III
Atmos. Meas. Tech., 11, 2937–2947, https://doi.org/10.5194/amt-11-2937-2018, https://doi.org/10.5194/amt-11-2937-2018, 2018
Short summary
Short summary
OH*-spectrometer measurements allow the analysis of gravity wave ground-based periods, but spatial information cannot necessarily be deduced. We combine the approach of Wachter at al. (2015) in order to derive horizontal wavelengths (but based on only one OH* spectrometer) with additional information about wind and temperature and compute vertical wavelengths. Knowledge of these parameters is a precondition for the calculation of further information such as the wave group velocity.
Laysa C. A. Resende, Christina Arras, Inez S. Batista, Clezio M. Denardini, Thainá O. Bertollotto, and Juliano Moro
Ann. Geophys., 36, 587–593, https://doi.org/10.5194/angeo-36-587-2018, https://doi.org/10.5194/angeo-36-587-2018, 2018
Short summary
Short summary
We present new results on the behavior of sporadic E layers (Es layers) using GPS (global positioning system) radio occultation (RO) measurements obtained from the FORMOSAT-3/COSMIC satellites and digisonde data over Cachoeira Paulista, a low-latitude station in Brazil.
Christoph Jacobi, Tatiana Ermakova, Daniel Mewes, and Alexander I. Pogoreltsev
Adv. Radio Sci., 15, 199–206, https://doi.org/10.5194/ars-15-199-2017, https://doi.org/10.5194/ars-15-199-2017, 2017
Short summary
Short summary
There is continuous interest in coupling processes between the lower and middle atmosphere. Here we analyse midlatitude winds measured by radar at 82–97 km and find that especially in February they are positively correlated with El Niño. The signal is strong for the upper altitudes accessible to the radar, but weakens below. The observations can be qualitatively reproduced by numerical experiments using a mechanistic global circulation model.
Friederike Lilienthal, Christoph Jacobi, Torsten Schmidt, Alejandro de la Torre, and Peter Alexander
Ann. Geophys., 35, 785–798, https://doi.org/10.5194/angeo-35-785-2017, https://doi.org/10.5194/angeo-35-785-2017, 2017
Short summary
Short summary
Gravity waves (GWs) are one of the most important dynamical features of the middle atmosphere that extends from the tropopause to the lower thermosphere. They originate from the troposphere and propagate upward. Here, we show the impact of the horizontal GW distribution in the lower atmosphere on the dynamics of the middle atmosphere using a global circulation model. As a result, we find that non-zonal GW structures can force additional stationary planetary waves.
Gunter Stober, Vivien Matthias, Christoph Jacobi, Sven Wilhelm, Josef Höffner, and Jorge L. Chau
Ann. Geophys., 35, 711–720, https://doi.org/10.5194/angeo-35-711-2017, https://doi.org/10.5194/angeo-35-711-2017, 2017
Petr Šácha, Friederike Lilienthal, Christoph Jacobi, and Petr Pišoft
Atmos. Chem. Phys., 16, 15755–15775, https://doi.org/10.5194/acp-16-15755-2016, https://doi.org/10.5194/acp-16-15755-2016, 2016
Short summary
Short summary
With a mechanistic model for the middle and upper atmosphere we performed sensitivity simulations to study a possible impact of a localized GW breaking hotspot in the eastern Asia–northern Pacific region and also the possible influence of the spatial distribution of gravity wave activity on the middle atmospheric circulation and transport. We show implications for polar vortex stability, in situ PW generation and longitudinal variability and strength of the Brewer–Dobson circulation.
Ch. Jacobi, N. Samtleben, and G. Stober
Adv. Radio Sci., 14, 169–174, https://doi.org/10.5194/ars-14-169-2016, https://doi.org/10.5194/ars-14-169-2016, 2016
Short summary
Short summary
VHF meteor radar observations of mesosphere/lower thermosphere daily temperatures have been performed at Collm, Germany. The data have been analyzed with respect to long-period oscillations at time scales of 2 to 30 days. The results reveal that oscillations with periods of up to 6 days are more frequently observed during summer, while those with longer periods have larger amplitudes during winter. The results are comparable with analyses from radar wind measurements.
Christoph Jacobi, Norbert Jakowski, Gerhard Schmidtke, and Thomas N. Woods
Adv. Radio Sci., 14, 175–180, https://doi.org/10.5194/ars-14-175-2016, https://doi.org/10.5194/ars-14-175-2016, 2016
Short summary
Short summary
The ionospheric response to solar extreme ultraviolet variability is shown by simple proxies based on Solar Dynamics Observatory/Extreme Ultraviolet Variability Experiment solar spectra. The daily proxies are compared with global mean total electron content. At time scales of the solar rotation up to about 40 days there is a time lag between EUV and TEC variability of about one day, with a tendency to increase for longer time scales.
P. Šácha, A. Kuchař, C. Jacobi, and P. Pišoft
Atmos. Chem. Phys., 15, 13097–13112, https://doi.org/10.5194/acp-15-13097-2015, https://doi.org/10.5194/acp-15-13097-2015, 2015
Short summary
Short summary
In this study, we present a discovery of an internal gravity wave activity and breaking hotspot collocated with an area of anomalously low annual cycle amplitude and specific dynamics in the stratosphere over the Northeastern Pacific/Eastern Asia coastal region. The reasons why this particular IGW activity hotspot was not discovered before nor the specific dynamics of this region pointed out are discussed together with possible consequences on the middle atmospheric dynamics and transport.
F. Lilienthal and Ch. Jacobi
Atmos. Chem. Phys., 15, 9917–9927, https://doi.org/10.5194/acp-15-9917-2015, https://doi.org/10.5194/acp-15-9917-2015, 2015
Short summary
Short summary
The quasi 2-day wave (QTDW), one of the most striking features in the mesosphere/lower thermosphere, is analyzed using meteor radar measurements at Collm (51°N, 13°E) during 2004-2014. The QTDW has periods lasting between 43 and 52h during strong summer bursts, and weaker enhancements are found during winter. A correlation between QTDW amplitudes and wind shear suggests baroclinic instability to be a likely forcing mechanism.
G. Schmidtke, Ch. Jacobi, B. Nikutowski, and Ch. Erhardt
Adv. Radio Sci., 12, 251–260, https://doi.org/10.5194/ars-12-251-2014, https://doi.org/10.5194/ars-12-251-2014, 2014
Ch. Jacobi
Adv. Radio Sci., 12, 161–165, https://doi.org/10.5194/ars-12-161-2014, https://doi.org/10.5194/ars-12-161-2014, 2014
F. Lilienthal and Ch. Jacobi
Adv. Radio Sci., 12, 205–210, https://doi.org/10.5194/ars-12-205-2014, https://doi.org/10.5194/ars-12-205-2014, 2014
Related subject area
Subject: Earth's ionosphere & aeronomy | Keywords: Ionosphere–atmosphere interactions
Entangled dynamos and Joule heating in the Earth's ionosphere
Evidence of vertical coupling: meteorological storm Fabienne on 23 September 2018 and its related effects observed up to the ionosphere
Quasi-10 d wave modulation of an equatorial ionization anomaly during the Southern Hemisphere stratospheric warming of 2002
Stephan C. Buchert
Ann. Geophys., 38, 1019–1030, https://doi.org/10.5194/angeo-38-1019-2020, https://doi.org/10.5194/angeo-38-1019-2020, 2020
Short summary
Short summary
Winds in the Earth's upper atmosphere cause magnetic and electric variations both at the ground and in space all over the Earth. According to the model of entangled dynamos the true cause is wind differences between regions in the Northern and Southern Hemispheres that are connected by the Earth's dipole-like magnetic field. The power produced in the southern dynamo heats the northern upper atmosphere and vice versa. The dynamos exist owing to this entanglement, an analogy to quantum mechanics.
Petra Koucká Knížová, Kateřina Podolská, Kateřina Potužníková, Daniel Kouba, Zbyšek Mošna, Josef Boška, and Michal Kozubek
Ann. Geophys., 38, 73–93, https://doi.org/10.5194/angeo-38-73-2020, https://doi.org/10.5194/angeo-38-73-2020, 2020
Short summary
Short summary
Severe meteorological storm Fabienne passing above central Europe was observed. Significant variations of atmospheric and ionospheric parameters were detected. Above Europe, stratospheric temperature and wind significantly changed in coincidence with frontal transition. Within ionospheric parameters, we have detected significant wave-like activity shortly after the cold front crossed the observational point. During the storm event, we have observed strong horizontal plasma flow shears.
Xiaohua Mo and Donghe Zhang
Ann. Geophys., 38, 9–16, https://doi.org/10.5194/angeo-38-9-2020, https://doi.org/10.5194/angeo-38-9-2020, 2020
Cited articles
Anthes, R. A., Bernhardt, P. A., Chen, Y., Cucurull, L., Dymond, K. F., Ector,
D., Healy, S. B., Ho, S.-P., Hunt, D. C., Kuo, Y.-H., Liu, H., Manning, K.,
McCormick, C., Meehan, T. K., Randel, W. J., Rocken, C., Schreiner, W. S.,
Sokolovskiy, S. V., Syndergaard, S., Thompson, D. C., Trenberth, K. E., Wee,
T.-K., Yen, N. L., and Zeng, Z.: The COSMIC/FORMOSAT-3 Mission: Early
Results, B. Am. Meteorol. Soc., 89, 313–334,
https://doi.org/10.1175/BAMS-89-3-313, 2008. a
Arras, C. and Wickert, J.: Estimation of ionospheric sporadic E intensities
from GPS radio occultation measurements, J. Atmos. Sol.-Terr. Phys., 171, 60–63, https://doi.org/10.1016/j.jastp.2017.08.006, 2018. a, b, c, d
Arras, C., Wickert, J., Beyerle, G., Heise, S., Schmidt, T., and Jacobi, C.: A
global climatology of ionospheric irregularities derived from GPS radio
occultation, Geophys. Res. Lett., 35, L14809, https://doi.org/10.1029/2008GL034158,
2008. a, b, c, d
Arras, C., Jacobi, C., Wickert, J., Heise, S., and Schmidt, T.: Sporadic E
signatures revealed from multi-satellite radio occultation measurements, Adv.
Radio Sci., 8, 225–230, https://doi.org/10.5194/ars-8-225-2010, 2010. a
Azeem, I., Walterscheid, R. L., Crowley, G., Bishop, R. L., and Christensen,
A. B.: Observations of the migrating semidiurnal and quaddiurnal tides from
the RAIDS/NIRS instrument, J. Geophys. Res.-Space, 121, 4626–4637,
https://doi.org/10.1002/2015JA022240, 2016. a, b
Bishop, R. L. and Earle, G. D.: Metallic ion transport associated with
midlatitude intermediate layer development, J. Geophys. Res.-Space,
108, SIA 3-1–SIA 3-8, https://doi.org/10.1029/2002JA009411, 2003. a
Chu, Y. H., Wang, C. Y., Wu, K. H., Chen, K. T., Tzeng, K. J., Su, C. L., Feng,
W., and Plane, J. M. C.: Morphology of sporadic E layer retrieved from COSMIC
GPS radio occultation measurements: Wind shear theory examination, J.
Geophys. Res.-Space, 119, 2117–2136, https://doi.org/10.1002/2013JA019437,
2014. a, b
Ermakova, T. S., Statnaya, I. A., Fedulina, I. N., Suvorova, E. V., and
Pogoreltsev, A. I.: Three-dimensional semi-empirical climate model of water
vapor distribution and its implementation to the radiation module of the
middle and upper atmosphere model, Russ. Meteorol. Hydrol., 42, 594–600,
https://doi.org/10.3103/S1068373917090060, 2017. a
Fröhlich, K., Pogoreltsev, A., and Jacobi, C.: Numerical simulation of
tides, Rossby and Kelvin waves with the COMMA-LIM model, Adv. Space Res.,
32, 863–868, https://doi.org/10.1016/S0273-1177(03)00416-2, 2003b. a, b
Fytterer, T., Arras, C., and Jacobi, C.: Terdiurnal signatures in sporadic E
layers at midlatitudes, Adv. Radio Sci., 11, 333–339,
https://doi.org/10.5194/ars-11-333-2013, 2013. a, b, c, d
Guharay, A., Batista, P. P., Buriti, R. A., and Schuch, N. J.: On the
variability of the quarter-diurnal tide in the MLT over Brazilian
low-latitude stations, Earth Planets Space, 70, 140,
https://doi.org/10.1186/s40623-018-0910-9, 2018. a
Hajj, G., Kursinski, E., Romans, L., Bertiger, W., and Leroy, S.: A technical
description of atmospheric sounding by GPS occultation, J. Atmos. Sol.-Terr.
Phys., 64, 451–469, https://doi.org/10.1016/S1364-6826(01)00114-6, 2002. a, b
Haldoupis, C.: Midlatitude Sporadic E. A Typical Paradigm of
Atmosphere-Ionosphere Coupling, Space Sci. Rev., 168, 441–461,
https://doi.org/10.1007/s11214-011-9786-8, 2012. a, b
Haldoupis, C., Meek, C., Christakis, N., Pancheva, D., and Bourdillon, A.:
Ionogram height-time-intensity observations of descending sporadic E
layers at mid-latitude, J. Atmos. Sol.-Terr. Phys., 68, 539–557,
https://doi.org/10.1016/j.jastp.2005.03.020, 2006. a
Haldoupis, C., Pancheva, D., Singer, W., Meek, C., and MacDougall, J.: An
explanation for the seasonal dependence of midlatitude sporadic E layers, J.
Geophys. Res.-Space, 112, A06315, https://doi.org/10.1029/2007JA012322,
2007. a, b
Hocking, W., Fuller, B., and Vandepeer, B.: Real-time determination of
meteor-related parameters utilizing modern digital technology, J. Atmos.
Sol.-Terr. Phys., 63, 155–169, https://doi.org/10.1016/S1364-6826(00)00138-3, 2001. a
Hupe, P., Ceranna, L., and Pilger, C.: Using barometric time series of the
IMS infrasound network for a global analysis of thermally induced atmospheric
tides, Atmos. Meas. Tech., 11, 2027–2040,
https://doi.org/10.5194/amt-11-2027-2018, 2018. a
Jacobi, C.: 6 year mean prevailing winds and tides measured by VHF meteor
radar over Collm (51.3∘ N, 13.0∘ E), J. Atmos. Sol.-Terr. Phys., 78–79,
8–18, https://doi.org/10.1016/j.jastp.2011.04.010, 2012. a, b
Jacobi, C., Fröhlich, K., and Pogoreltsev, A.: Quasi two-day-wave
modulation of gravity wave flux and consequences for the planetary wave
propagation in a simple circulation model, J. Atmos. Sol.-Terr. Phys., 68,
283–292, https://doi.org/10.1016/j.jastp.2005.01.017, 2006. a, b
Jacobi, C., Geißler, C., Lilienthal, F., and Krug, A.: Forcing mechanisms
of the 6 h tide in the mesosphere/lower thermosphere, Adv. Radio Sci., 16,
141–147, https://doi.org/10.5194/ars-16-141-2018, 2018. a, b
Jakobs, H. J., Bischof, M., Ebel, A., and Speth, P.: Simulation of gravity
wave effects under solstice conditions using a 3-D circulation model of the
middle atmosphere, J. Atmos. Sol.-Terr. Phys., 48, 1203–1223,
https://doi.org/10.1016/0021-9169(86)90040-1, 1986. a
Kursinski, E. R., Hajj, G. A., Schofield, J. T., Linfield, R. P., and Hardy,
K. R.: Observing Earth's atmosphere with radio occultation measurements using
the Global Positioning System, J. Geophys. Res.-Atmos., 102,
23429–23465, https://doi.org/10.1029/97JD01569, 1997. a
Lilienthal, F. and Jacobi, C.: Meteor radar quasi 2-day wave observations over
10 years at Collm (51.3∘ N, 13.0∘ E), Atmos. Chem. Phys., 15, 9917–9927,
https://doi.org/10.5194/acp-15-9917-2015, 2015. a
Lilienthal, F., Jacobi, C., Schmidt, T., de la Torre, A., and Alexander, P.:
On the influence of zonal gravity wave distributions on the Southern
Hemisphere winter circulation, Ann. Geophys., 35, 785–798,
https://doi.org/10.5194/angeo-35-785-2017, 2017. a
Lilienthal, F., Jacobi, C., and Geißler, C.: Forcing mechanisms of the
terdiurnal tide, Atmos. Chem. Phys., 18, 15725–15742,
https://doi.org/10.5194/acp-18-15725-2018, 2018. a, b
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
Liu, M., Xu, J., Yue, J., and Jiang, G.: Global structure and seasonal
variations of the migrating 6-h tide observed by SABER/TIMED, Sci. China
Earth Sci., 58, 1216–1227, https://doi.org/10.1007/s11430-014-5046-6, 2015. a, b, c, d
Liu, R., Lu, D., Yi, F., and Hu, X.: Quadratic nonlinear interactions between
atmospheric tides in the mid-latitude winter lower thermosphere, J. Atmos.
Sol.-Terr. Phys., 68, 1245–1259, https://doi.org/10.1016/j.jastp.2006.03.004, 2006. a
Liu, Y., Zhou, C., Tang, Q., Li, Z., Song, Y., Qing, H., Ni, B., and Zhao, Z.:
The seasonal distribution of sporadic E layers observed from radio
occultation measurements and its relation with wind shear measured by
TIMED/TIDI, Adv. Space Res., 62, 426–439, https://doi.org/10.1016/j.asr.2018.04.026,
2018. a
Mathews, J.: Sporadic E: current views and recent progress, J. Atmos.
Sol.-Terr. Phys., 60, 413–435, https://doi.org/10.1016/S1364-6826(97)00043-6, 1998. a
Morton, Y. T., Mathews, J., and Zhou, Q.: Further evidence for a 6-h tide above
Arecibo, J. Atmos. Terr. Phys., 55, 459–465,
https://doi.org/10.1016/0021-9169(93)90081-9, 1993. a
NOAA ESRL Global Monitoring Division: Atmospheric Carbon Dioxide Dry Air
Mole Fractions from quasi-continuous measurements at Mauna Loa, Hawaii,
National Oceanic and Atmospheric Administration (NOAA), Earth System Research
Laboratory (ESRL), Global Monitoring Division (GMD): Boulder, Colorado, USA,
compiled by: Thoning, K. W., Kitzis, D. R., and Crotwell, A., Version 2015-12,
updated annually, 2018. a
Oikonomou, C., Haralambous, H., Haldoupis, C., and Meek, C.: Sporadic E tidal
variabilities and characteristics observed with the Cyprus Digisonde, J.
Atmos. Sol.-Terr. Phys., 119, 173–183, https://doi.org/10.1016/j.jastp.2014.07.014,
2014. a, b
Pogoreltsev, A. I.: Generation of normal atmospheric modes by stratospheric
vacillations, Izv. Atmos. Ocean. Phys., 43, 423–435,
https://doi.org/10.1134/S0001433807040044, 2007. a
Pogoreltsev, A. I., Vlasov, A. A., Fröhlich, K., and Jacobi, C.: Planetary
waves in coupling the lower and upper atmosphere, J. Atmos. Sol.-Terr.
Phys., 69, 2083–2101, https://doi.org/10.1016/j.jastp.2007.05.014, 2007. 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
Randel, W. J. and Wu, F.: A stratospheric ozone profile data set for
1979–2005: Variability, trends, and comparisons with column ozone data, J.
Geophys. Res.-Atmos., 112, D06313, https://doi.org/10.1029/2006JD007339, 2007. a
Resende, L. C. A., Arras, C., Batista, I. S., Denardini, C. M., Bertollotto,
T. O., and Moro, J.: Study of sporadic E layers based on GPS radio
occultation measurements and digisonde data over the Brazilian region, Ann.
Geophys., 36, 587–593, https://doi.org/10.5194/angeo-36-587-2018, 2018a. a
Resende, L. C. A., Batista, I. S., Denardini, C. M., Batista, P. P., Carrasco,
A. J., Andrioli, V. F., and Moro, J.: The influence of tidal winds in the
formation of blanketing sporadic e-layer over equatorial Brazilian region, J.
Atmos. Sol.-Terr. Phys., 171, 64–71,
https://doi.org/10.1016/j.jastp.2017.06.009, 2018b. a
Riese, M., Offermann, D., and Brasseur, G.: Energy released by recombination
of atomic oxygen and related species at mesopause heights, J. Geophys. Res.-Atmos., 99, 14585–14593, https://doi.org/10.1029/94JD00356, 1994. a
Shinagawa, H., Miyoshi, Y., Jin, H., and Fujiwara, H.: Global distribution of
neutral wind shear associated with sporadic E layers derived from GAIA, J.
Geophys. Res.-Space, 122, 4450–4465, https://doi.org/10.1002/2016JA023778,
2017. 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., Jacobi, C., Fröhlich, K., and Oberheide, J.: Meteor radar
temperatures over Collm (51.3∘ N, 13∘ E), Adv. Space Res., 42, 1253–1258,
https://doi.org/10.1016/j.asr.2007.10.018, 2008. a
Stober, G., Jacobi, C., Matthias, V., Hoffmann, P., and Gerding, M.: Neutral
air density variations during strong planetary wave activity in the mesopause
region derived from meteor radar observations, J. Atmos. Sol.-Terr. Phys.,
74, 55–63, https://doi.org/10.1016/j.jastp.2011.10.007, 2012. a
Stober, G., Matthias, V., Jacobi, C., Wilhelm, S., Höffner, J., and Chau,
J. L.: Exceptionally strong summer-like zonal wind reversal in the upper
mesosphere during winter 2015/16, Ann. Geophys., 35, 711–720,
https://doi.org/10.5194/angeo-35-711-2017, 2017. a
Strobel, D. F.: Parameterization of the atmospheric heating rate from 15 to
120 km due to O2 and O3 absorption of solar radiation, J. Geophys. Res.-Oceans, 83, 6225–6230, https://doi.org/10.1029/JC083iC12p06225, 1978. a
Suvorova, E. V. and Pogoreltsev, A. I.: Modeling of nonmigrating tides in the
middle atmosphere, Geomagn. Aeronomy, 51, 105–115,
https://doi.org/10.1134/S0016793210061039, 2011. a
Tong, Y., Mathews, J. D., and Ying, W. P.: An upper E region quarterdiurnal
tide at Arecibo?, J. Geophys. Res.-Space, 93, 10047–10051,
https://doi.org/10.1029/JA093iA09p10047, 1988. a
UCAR: http://cdaac-www.cosmic.ucar.edu/cdaac/products.html, last access: 26 September 2018. a
Warburton, R. J. and Goodkind, J. M.: The influence of barometric-pressure
variations on gravity, Geophys. J. Int., 48, 281–292,
https://doi.org/10.1111/j.1365-246X.1977.tb03672.x, 1977. a
Whitehead, J.: The formation of the sporadic-E layer in the temperate zones, J.
Atmos. Terr. Phys., 20, 49–58, https://doi.org/10.1016/0021-9169(61)90097-6, 1961.
a
Xu, J., Smith, A. K., Jiang, G., Yuan, W., and Gao, H.: Features of the
seasonal variation of the semidiurnal, terdiurnal and 6-h components of ozone
heating evaluated from Aura/MLS observations, Ann. Geophys., 30, 259–281,
https://doi.org/10.5194/angeo-30-259-2012, 2012. a
Xu, J., Smith, A. K., Liu, M., Liu, X., Gao, H., Jiang, G., and Yuan, W.:
Evidence for nonmigrating tides produced by the interaction between tides and
stationary planetary waves in the stratosphere and lower mesosphere, J.
Geophys. Res.-Atmos., 119, 471–489, https://doi.org/10.1002/2013JD020150, 2014. a
Yiǧit, E. and Medvedev, A. S.: Internal wave coupling processes in
Earth's atmosphere, Adv. Space Res., 55, 983–1003,
https://doi.org/10.1016/j.asr.2014.11.020, 2015. a
Yiǧit, E., Aylward, A., and Medvedev, A.: Parameterization of the effects
of vertically propagating gravity waves for thermosphere general circulation
models: Sensitivity study, J. Geophys. Res.-Atmos., 113, D19106,
https://doi.org/10.1029/2008JD010135, 2008. a
Yiǧit, E., Medvedev, A. S., Aylward, A. D., Hartogh, P., and Harris, M. J.:
Modeling the effects of gravity wave momentum deposition on the general
circulation above the turbopause, J. Geophys. Res.-Atmos., 114,
D07101, https://doi.org/10.1029/2008JD011132, 2009. a
Special issue
Short summary
Sporadic E (Es) layers in the Earth's ionosphere are produced by ion convergence due to vertical wind shear in the presence of a horizontal component of the Earth's magnetic field. We present analyses of the 6 h tidal signatures in ES occurrence rates derived from GPS radio observations. Times of maxima in ES agree well with those of negative wind shear obtained from radar observation. The global distribution of ES amplitudes agrees with wind shear amplitudes from numerical modeling.
Sporadic E (Es) layers in the Earth's ionosphere are produced by ion convergence due to vertical...