Articles | Volume 36, issue 1
https://doi.org/10.5194/angeo-36-265-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Special issue:
https://doi.org/10.5194/angeo-36-265-2018
© Author(s) 2018. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Regular paper
| 
28 Feb 2018
Regular paper |
| 28 Feb 2018
| 28 Feb 2018
Intrinsic parameters of periodic waves observed in the OI6300 airglow layer over the Brazilian equatorial region
Universidade Federal de Campina Grande, Campina Grande, PB, Brazil
Joyrles F. Moraes
Universidade Federal de Campina Grande, Campina Grande, PB, Brazil
Gleuson L. Maranhão
Universidade Federal de Campina Grande, Campina Grande, PB, Brazil
Cristiano M. Wrasse
Instituto Nacional de Pesquisas Espaciais, São José dos Campos, SP, Brazil
Ricardo Arlen Buriti
Universidade Federal de Campina Grande, Campina Grande, PB, Brazil
Amauri F. Medeiros
Universidade Federal de Campina Grande, Campina Grande, PB, Brazil
Ana Roberta Paulino
Universidade Federal de Campina Grande, Campina Grande, PB, Brazil
Universidade Estadual da Paraíba, Campina Grande, PB, Brazil
Hisao Takahashi
Instituto Nacional de Pesquisas Espaciais, São José dos Campos, SP, Brazil
Jonathan J. Makela
University of Illinois, Urbana-Champaign, IL, USA
John W. Meriwether
Clemson University, Clemson, SC, USA
José André V. Campos
Universidade Federal de Campina Grande, Campina Grande, PB, Brazil
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Ana Roberta Paulino, Delis Otildes Rodrigues, Igo Paulino, Lourivaldo Mota Lima, Ricardo Arlen Buriti, Paulo Prado Batista, Aaron Ridley, and Chen Wu
Ann. Geophys. Discuss., https://doi.org/10.5194/angeo-2023-23, https://doi.org/10.5194/angeo-2023-23, 2023
Revised manuscript under review for ANGEO
Short summary
Short summary
Comparisons of wind measurements using two different techniques (ground based radar and satellite) in Brasil during 2006 were made in order to point out the advantage of each instrument for studies in the mesosphere and upper thermosphere. (i) For short period variations, the measurements of the satellite was more advantageous. (ii) The month climatology using the radar were more appropriate. (iii) If the long period (longer than few months), both instruments responded satisfactorily.
Hisao Takahashi, Cosme A. O. B. Figueiredo, Patrick Essien, Cristiano M. Wrasse, Diego Barros, Prosper K. Nyassor, Igo Paulino, Fabio Egito, Geangelo M. Rosa, and Antonio H. R. Sampaio
Ann. Geophys., 40, 665–672, https://doi.org/10.5194/angeo-40-665-2022, https://doi.org/10.5194/angeo-40-665-2022, 2022
Short summary
Short summary
We observed two different wave propagations in the earth’s upper atmosphere: a gravity wave in the mesosphere and the ionospheric disturbances. We investigated the wave propagations by using airglow imaging techniques. It is found that there was a gravity wave generation from the tropospheric convection spot, and it propagated upward in the ionosphere. This reports observational evidence of gravity wave propagation from the troposphere to ionosphere.
Prosper K. Nyassor, Cristiano M. Wrasse, Igo Paulino, Eliah F. M. T. São Sabbas, José V. Bageston, Kleber P. Naccarato, Delano Gobbi, Cosme A. O. B. Figueiredo, Toyese T. Ayorinde, Hisao Takahashi, and Diego Barros
Atmos. Chem. Phys., 22, 15153–15177, https://doi.org/10.5194/acp-22-15153-2022, https://doi.org/10.5194/acp-22-15153-2022, 2022
Short summary
Short summary
This work investigates the sources of concentric gravity waves (CGWs) excited by a moving system of clouds with several overshooting regions on 1–2 October 2019 at São Martinho da Serra. The parameters of these waves were estimated using 2D spectral analysis and their source locations identified using backward ray tracing. Furthermore, the sources of these waves were properly identified by tracking the individual overshooting regions in space and time since the system of clouds was moving.
Igo Paulino, Ana Roberta Paulino, Amauri F. Medeiros, Cristiano M. Wrasse, Ricardo Arlen Buriti, and Hisao Takahashi
Ann. Geophys., 39, 1005–1012, https://doi.org/10.5194/angeo-39-1005-2021, https://doi.org/10.5194/angeo-39-1005-2021, 2021
Short summary
Short summary
In the present work, the lunar semidiurnal tide (M2) was investigated in the equatorial plasma bubble (EPB) zonal drifts over Brazil from 2000 to 2007. On average, the M2 contributes 5.6 % to the variability of the EPB zonal drifts. A strong seasonal and solar cycle dependency was also observed, the amplitudes of the M2 being stronger during the summer and high solar activity periods.
Ana Roberta Paulino, Fabiano da Silva Araújo, Igo Paulino, Cristiano Max Wrasse, Lourivaldo Mota Lima, Paulo Prado Batista, and Inez Staciarini Batista
Ann. Geophys., 39, 151–164, https://doi.org/10.5194/angeo-39-151-2021, https://doi.org/10.5194/angeo-39-151-2021, 2021
Short summary
Short summary
Long- and short-period oscillations in the lunar semidiurnal tidal amplitudes in the ionosphere derived from the total electron content were investigated over Brazil from 2011 to 2014. The results showed annual, semiannual and triannual oscillations as the dominant components. Additionally, the most pronounced short-period oscillations were observed between 7 and 11 d, which suggest a possible coupling of the lunar tide and planetary waves.
Ricardo A. Buriti, Wayne Hocking, Paulo P. Batista, Igo Paulino, Ana R. Paulino, Marcial Garbanzo-Salas, Barclay Clemesha, and Amauri F. Medeiros
Ann. Geophys., 38, 1247–1256, https://doi.org/10.5194/angeo-38-1247-2020, https://doi.org/10.5194/angeo-38-1247-2020, 2020
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Solar atmospheric tides are natural oscillations of 24, 12, 8... hours that contribute to the circulation of the atmosphere from low to high altitudes. The Sun heats the atmosphere periodically because, mainly, water vapor and ozone absorb solar radiation between the ground and 50 km height during the day. Tides propagate upward and they can be observed in, for example, the wind field. This work presents diurnal tides observed by meteor radars which measure wind between 80 and 100 km height.
Joyrles Fernandes de Moraes, Igo Paulino, Lívia R. Alves, and Clezio Marcos Denardini
Ann. Geophys., 38, 881–888, https://doi.org/10.5194/angeo-38-881-2020, https://doi.org/10.5194/angeo-38-881-2020, 2020
Short summary
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Effects of space weather events in technological systems were studied in the tropical region of Brazil by investigating the Bolivia–Brazil pipeline during space weather events with different intensities. The results presented significant corrosion levels during the 17 March 2015 geomagnetic storm and showed that the effects of space weather must be accounted for, even in low latitudes, since the lifetime of the pipelines can be reduced.
Oluwakemi Dare-Idowu, Igo Paulino, Cosme A. O. B. Figueiredo, Amauri F. Medeiros, Ricardo A. Buriti, Ana Roberta Paulino, and Cristiano M. Wrasse
Ann. Geophys., 38, 507–516, https://doi.org/10.5194/angeo-38-507-2020, https://doi.org/10.5194/angeo-38-507-2020, 2020
Short summary
Short summary
Some strong gravity wave activity occurred and was observed on 8 April 2005. This work reports the spectral characteristics of these waves using OH airglow images captured by the all-sky imager installed at São João do Cariri (7.4° S, 36.5° W). A preferential propagation direction was observed due to the positioning of the source and also due to the wind filtering effect. Furthermore, the source of these waves was identified by performing reverse-ray tracing analysis.
Igo Paulino, Ana Roberta Paulino, Ricardo Y. C. Cueva, Ebenezer Agyei-Yeboah, Ricardo Arlen Buriti, Hisao Takahashi, Cristiano Max Wrasse, Ângela M. Santos, Amauri Fragoso de Medeiros, and Inez S. Batista
Ann. Geophys., 38, 437–443, https://doi.org/10.5194/angeo-38-437-2020, https://doi.org/10.5194/angeo-38-437-2020, 2020
Short summary
Short summary
In this paper, an extensive study has been done in order to investigate periodic oscillations in the start times of equatorial plasma bubbles observed over Brazil. Using OI6300 airglow images and ionograms, it was possible to detect semimonthly oscillations in the start times of equatorial plasma bubbles (EPBs) and equatorial Spread-F. This semimonthly oscillation is likely related to the lunar tide, which represents an important mechanism acting in the day-to-day variability of EPBs.
Patrick Essien, Igo Paulino, Cristiano Max Wrasse, Jose Andre V. Campos, Ana Roberta Paulino, Amauri F. Medeiros, Ricardo Arlen Buriti, Hisao Takahashi, Ebenezer Agyei-Yeboah, and Aline N. Lins
Ann. Geophys., 36, 899–914, https://doi.org/10.5194/angeo-36-899-2018, https://doi.org/10.5194/angeo-36-899-2018, 2018
Short summary
Short summary
Present work reports seasonal characteristics of small- and medium-scale gravity waves in the mesosphere and lower thermosphere region. All-sky images of the hydroxyl airglow emission layer over São João do Cariri (7.4° S, 36.5° W) were observed from September 2000 to December 2010, during a total of 1496 nights and obtained 2343 SSGW and 537 MSGW events. The horizontal propagation directions of SSGWs and MSGWs showed clear seasonal variations based on the influence of the wind filtering process.
Prosper K. Nyassor, Ricardo Arlen Buriti, Igo Paulino, Amauri F. Medeiros, Hisao Takahashi, Cristiano M. Wrasse, and Delano Gobbi
Ann. Geophys., 36, 705–715, https://doi.org/10.5194/angeo-36-705-2018, https://doi.org/10.5194/angeo-36-705-2018, 2018
Amauri Fragoso Medeiros, Igo Paulino, Cristiano Max Wrasse, Joaquim Fechine, Hisao Takahashi, José Valentin Bageston, Ana Roberta Paulino, and Ricardo Arlen Buriti
Ann. Geophys., 36, 311–319, https://doi.org/10.5194/angeo-36-311-2018, https://doi.org/10.5194/angeo-36-311-2018, 2018
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On 3 October 2005, a mesospheric front was observed over São João do Cariri (7.4° S, 36.5° W) propagating to the northeast in the OH airglow images. One and a half hours later, it disappeared completely and ripples were observed in the eastern part of the images. After studying the background atmosphere, the main conclusion of this work was that the instability in the airglow layer did not allow the propagation of the front to the other side of the local zenith.
Gabriel Augusto Giongo, José Valentin Bageston, Paulo Prado Batista, Cristiano Max Wrasse, Gabriela Dornelles Bittencourt, Igo Paulino, Neusa Maria Paes Leme, David C. Fritts, Diego Janches, Wayne Hocking, and Nelson Jorge Schuch
Ann. Geophys., 36, 253–264, https://doi.org/10.5194/angeo-36-253-2018, https://doi.org/10.5194/angeo-36-253-2018, 2018
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This work presents four events of mesosphere fronts observed on King George Island, Antarctic Peninsula, in the year 2011. The atmospheric background environment was analyzed to investigate the propagation conditions for all cases. To investigate the sources for such cases, satellite images were used. In two cases, we found that strong tropospheric instabilities were potential sources, and in the other two cases, it was not possible to associate them with tropospheric sources.
Cosme Alexandre O. B. Figueiredo, Ricardo A. Buriti, Igo Paulino, John W. Meriwether, Jonathan J. Makela, Inez S. Batista, Diego Barros, and Amauri F. Medeiros
Ann. Geophys., 35, 953–963, https://doi.org/10.5194/angeo-35-953-2017, https://doi.org/10.5194/angeo-35-953-2017, 2017
I. Paulino, A. F. Medeiros, S. L. Vadas, C. M. Wrasse, H. Takahashi, R. A. Buriti, D. Leite, S. Filgueira, J. V. Bageston, J. H. A. Sobral, and D. Gobbi
Ann. Geophys., 34, 293–301, https://doi.org/10.5194/angeo-34-293-2016, https://doi.org/10.5194/angeo-34-293-2016, 2016
Short summary
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Periodic waves have been observed over São João do Cariri during almost one solar cycle. Similarities between the characteristics of these events with observations at other places around the world were noted, primarily the spectral parameters. Most observed waves have appeared during magnetically quiet nights, and the occurrence of those waves followed the solar activity. Due to their characteristics, most of them must have had different generation mechanisms from the Perkins instability.
A. F. Medeiros, I. Paulino, M. J. Taylor, J. Fechine, H. Takahashi, R. A. Buriti, L. M. Lima, and C. M. Wrasse
Ann. Geophys., 34, 91–96, https://doi.org/10.5194/angeo-34-91-2016, https://doi.org/10.5194/angeo-34-91-2016, 2016
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This paper reports two consecutive mesospheric bores observed in the airglow emissions (OH and OI5577). Both bores propagated to the east and showed similar spectral characteristics. However, the first one exhibited a dark leading front with several trailing waves behind and progressed into a brighter airglow region. However, the second bore, observed in the OH layer, was comprised of several bright waves propagating into a darker airglow region.
M. Sivakandan, I. Paulino, A. Taori, and K. Niranjan
Atmos. Meas. Tech., 9, 93–102, https://doi.org/10.5194/amt-9-93-2016, https://doi.org/10.5194/amt-9-93-2016, 2016
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The small-scale gravity waves are the least understood processes in the middle-atmospheric variability. Using airglow imaging, we provide new measurements of gravity wave propagation over equatorial latitudes in India. We find that propagation of waves is often in the opposite direction to the tropospheric convective regions. These waves are found to have horizontal wavelengths ranging from 12 to 42 km, with the phase velocities in the 20 to 90 km range.
Cristiano M. Wrasse, Prosper K. Nyassor, Ligia A. da Silva, Cosme O. A. B. Figueiredo, José V. Bageston, Kleber P. Naccarato, Diego Barros, Hisao Takahashi, and Delano Gobbi
EGUsphere, https://doi.org/10.5194/egusphere-2023-1825, https://doi.org/10.5194/egusphere-2023-1825, 2023
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This present work investigates the propagation dynamics and the sources-source mechanisms of quasi-monochromatic gravity waves (QMGWs) observed between April, 2017 and April, 2022 at São Martinho da Serra. The QMGW parameters were estimated using a 2D spectral analysis, and their source locations were identified using a backward ray tracing model. Furthermore, the propagation conditions, sources, and source mechanisms of the QMGWs were extensively studied.
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, and Na Li
EGUsphere, https://doi.org/10.5194/egusphere-2023-1714, https://doi.org/10.5194/egusphere-2023-1714, 2023
Short summary
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On 15th 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 volcanic-caused 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.
Ana Roberta Paulino, Delis Otildes Rodrigues, Igo Paulino, Lourivaldo Mota Lima, Ricardo Arlen Buriti, Paulo Prado Batista, Aaron Ridley, and Chen Wu
Ann. Geophys. Discuss., https://doi.org/10.5194/angeo-2023-23, https://doi.org/10.5194/angeo-2023-23, 2023
Revised manuscript under review for ANGEO
Short summary
Short summary
Comparisons of wind measurements using two different techniques (ground based radar and satellite) in Brasil during 2006 were made in order to point out the advantage of each instrument for studies in the mesosphere and upper thermosphere. (i) For short period variations, the measurements of the satellite was more advantageous. (ii) The month climatology using the radar were more appropriate. (iii) If the long period (longer than few months), both instruments responded satisfactorily.
Hisao Takahashi, Cosme A. O. B. Figueiredo, Patrick Essien, Cristiano M. Wrasse, Diego Barros, Prosper K. Nyassor, Igo Paulino, Fabio Egito, Geangelo M. Rosa, and Antonio H. R. Sampaio
Ann. Geophys., 40, 665–672, https://doi.org/10.5194/angeo-40-665-2022, https://doi.org/10.5194/angeo-40-665-2022, 2022
Short summary
Short summary
We observed two different wave propagations in the earth’s upper atmosphere: a gravity wave in the mesosphere and the ionospheric disturbances. We investigated the wave propagations by using airglow imaging techniques. It is found that there was a gravity wave generation from the tropospheric convection spot, and it propagated upward in the ionosphere. This reports observational evidence of gravity wave propagation from the troposphere to ionosphere.
Prosper K. Nyassor, Cristiano M. Wrasse, Igo Paulino, Eliah F. M. T. São Sabbas, José V. Bageston, Kleber P. Naccarato, Delano Gobbi, Cosme A. O. B. Figueiredo, Toyese T. Ayorinde, Hisao Takahashi, and Diego Barros
Atmos. Chem. Phys., 22, 15153–15177, https://doi.org/10.5194/acp-22-15153-2022, https://doi.org/10.5194/acp-22-15153-2022, 2022
Short summary
Short summary
This work investigates the sources of concentric gravity waves (CGWs) excited by a moving system of clouds with several overshooting regions on 1–2 October 2019 at São Martinho da Serra. The parameters of these waves were estimated using 2D spectral analysis and their source locations identified using backward ray tracing. Furthermore, the sources of these waves were properly identified by tracking the individual overshooting regions in space and time since the system of clouds was moving.
Daniel D. Billett, Kathryn A. McWilliams, Robert B. Kerr, Jonathan J. Makela, Alex T. Chartier, J. Michael Ruohoniemi, Sudha Kapali, Mike A. Migliozzi, and Juanita Riccobono
Ann. Geophys., 40, 571–583, https://doi.org/10.5194/angeo-40-571-2022, https://doi.org/10.5194/angeo-40-571-2022, 2022
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Sub-auroral polarisation streams (SAPSs) are very fast plasma flows that occur at mid-latitudes, which can affect the atmosphere. In this paper, we use four ground-based radars to obtain a wide coverage of SAPSs that occurred over the USA, along with interferometer cameras in Virginia and Massachusetts to measure winds. The winds are strongly affected but in different ways, implying that the balance forces on the atmosphere is strongly dependent on proximity to the disturbance.
Igo Paulino, Ana Roberta Paulino, Amauri F. Medeiros, Cristiano M. Wrasse, Ricardo Arlen Buriti, and Hisao Takahashi
Ann. Geophys., 39, 1005–1012, https://doi.org/10.5194/angeo-39-1005-2021, https://doi.org/10.5194/angeo-39-1005-2021, 2021
Short summary
Short summary
In the present work, the lunar semidiurnal tide (M2) was investigated in the equatorial plasma bubble (EPB) zonal drifts over Brazil from 2000 to 2007. On average, the M2 contributes 5.6 % to the variability of the EPB zonal drifts. A strong seasonal and solar cycle dependency was also observed, the amplitudes of the M2 being stronger during the summer and high solar activity periods.
Ana Roberta Paulino, Fabiano da Silva Araújo, Igo Paulino, Cristiano Max Wrasse, Lourivaldo Mota Lima, Paulo Prado Batista, and Inez Staciarini Batista
Ann. Geophys., 39, 151–164, https://doi.org/10.5194/angeo-39-151-2021, https://doi.org/10.5194/angeo-39-151-2021, 2021
Short summary
Short summary
Long- and short-period oscillations in the lunar semidiurnal tidal amplitudes in the ionosphere derived from the total electron content were investigated over Brazil from 2011 to 2014. The results showed annual, semiannual and triannual oscillations as the dominant components. Additionally, the most pronounced short-period oscillations were observed between 7 and 11 d, which suggest a possible coupling of the lunar tide and planetary waves.
Ricardo A. Buriti, Wayne Hocking, Paulo P. Batista, Igo Paulino, Ana R. Paulino, Marcial Garbanzo-Salas, Barclay Clemesha, and Amauri F. Medeiros
Ann. Geophys., 38, 1247–1256, https://doi.org/10.5194/angeo-38-1247-2020, https://doi.org/10.5194/angeo-38-1247-2020, 2020
Short summary
Short summary
Solar atmospheric tides are natural oscillations of 24, 12, 8... hours that contribute to the circulation of the atmosphere from low to high altitudes. The Sun heats the atmosphere periodically because, mainly, water vapor and ozone absorb solar radiation between the ground and 50 km height during the day. Tides propagate upward and they can be observed in, for example, the wind field. This work presents diurnal tides observed by meteor radars which measure wind between 80 and 100 km height.
Joyrles Fernandes de Moraes, Igo Paulino, Lívia R. Alves, and Clezio Marcos Denardini
Ann. Geophys., 38, 881–888, https://doi.org/10.5194/angeo-38-881-2020, https://doi.org/10.5194/angeo-38-881-2020, 2020
Short summary
Short summary
Effects of space weather events in technological systems were studied in the tropical region of Brazil by investigating the Bolivia–Brazil pipeline during space weather events with different intensities. The results presented significant corrosion levels during the 17 March 2015 geomagnetic storm and showed that the effects of space weather must be accounted for, even in low latitudes, since the lifetime of the pipelines can be reduced.
Oluwakemi Dare-Idowu, Igo Paulino, Cosme A. O. B. Figueiredo, Amauri F. Medeiros, Ricardo A. Buriti, Ana Roberta Paulino, and Cristiano M. Wrasse
Ann. Geophys., 38, 507–516, https://doi.org/10.5194/angeo-38-507-2020, https://doi.org/10.5194/angeo-38-507-2020, 2020
Short summary
Short summary
Some strong gravity wave activity occurred and was observed on 8 April 2005. This work reports the spectral characteristics of these waves using OH airglow images captured by the all-sky imager installed at São João do Cariri (7.4° S, 36.5° W). A preferential propagation direction was observed due to the positioning of the source and also due to the wind filtering effect. Furthermore, the source of these waves was identified by performing reverse-ray tracing analysis.
Igo Paulino, Ana Roberta Paulino, Ricardo Y. C. Cueva, Ebenezer Agyei-Yeboah, Ricardo Arlen Buriti, Hisao Takahashi, Cristiano Max Wrasse, Ângela M. Santos, Amauri Fragoso de Medeiros, and Inez S. Batista
Ann. Geophys., 38, 437–443, https://doi.org/10.5194/angeo-38-437-2020, https://doi.org/10.5194/angeo-38-437-2020, 2020
Short summary
Short summary
In this paper, an extensive study has been done in order to investigate periodic oscillations in the start times of equatorial plasma bubbles observed over Brazil. Using OI6300 airglow images and ionograms, it was possible to detect semimonthly oscillations in the start times of equatorial plasma bubbles (EPBs) and equatorial Spread-F. This semimonthly oscillation is likely related to the lunar tide, which represents an important mechanism acting in the day-to-day variability of EPBs.
Claudia M. N. Candido, Jiankui Shi, Inez S. Batista, Fabio Becker-Guedes, Emília Correia, Mangalathayil A. Abdu, Jonathan Makela, Nanan Balan, Narayan Chapagain, Chi Wang, and Zhengkuan Liu
Ann. Geophys., 37, 657–672, https://doi.org/10.5194/angeo-37-657-2019, https://doi.org/10.5194/angeo-37-657-2019, 2019
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This study concerns postmidnight ionospheric irregularities observed during low solar activity conditions. We analyze data from digisondes and optical imaging systems located in an equatorial region over Brazil. The results show that they occur under unfavorable and unexpected conditions. This work can be useful for space weather forecasting during low solar activity.
Jean C. Santos and Cristiano M. Wrasse
Ann. Geophys., 37, 603–612, https://doi.org/10.5194/angeo-37-603-2019, https://doi.org/10.5194/angeo-37-603-2019, 2019
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We describe a technique used to locate and classify critical points in 2-D flow fields at the solar photosphere obtained from the evolution of the line-of-sight magnetic field in a region close to the magnetic polarity inversion line of a fully emerged active region. We apply this technique to locate a particular kind of critical point associated to vortex flows, which are considered important, since they can twist and interweave the foot points of flux tubes and generate magnetic reconnection.
Khalifa Malki, Aziza Bounhir, Zouhair Benkhaldoun, Jonathan J. Makela, Nicole Vilmer, Daniel J. Fisher, Mohamed Kaab, Khaoula Elbouyahyaoui, Brian J. Harding, Amine Laghriyeb, Ahmed Daassou, and Mohamed Lazrek
Ann. Geophys., 36, 987–998, https://doi.org/10.5194/angeo-36-987-2018, https://doi.org/10.5194/angeo-36-987-2018, 2018
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The novelty of this paper lies in the fact that it addresses the thermosphere–ionosphere coupling in a midlatitude site in north Africa. We have used Fabry–Perot measurements of thermospheric winds and wide-angle camera detection of ionospheric structures at an altitude of about 250 km. We have also used GPS data to extract the TEC over the studied area. We have focused our study on the 27 February geomagnetic storm.
Patrick Essien, Igo Paulino, Cristiano Max Wrasse, Jose Andre V. Campos, Ana Roberta Paulino, Amauri F. Medeiros, Ricardo Arlen Buriti, Hisao Takahashi, Ebenezer Agyei-Yeboah, and Aline N. Lins
Ann. Geophys., 36, 899–914, https://doi.org/10.5194/angeo-36-899-2018, https://doi.org/10.5194/angeo-36-899-2018, 2018
Short summary
Short summary
Present work reports seasonal characteristics of small- and medium-scale gravity waves in the mesosphere and lower thermosphere region. All-sky images of the hydroxyl airglow emission layer over São João do Cariri (7.4° S, 36.5° W) were observed from September 2000 to December 2010, during a total of 1496 nights and obtained 2343 SSGW and 537 MSGW events. The horizontal propagation directions of SSGWs and MSGWs showed clear seasonal variations based on the influence of the wind filtering process.
Prosper K. Nyassor, Ricardo Arlen Buriti, Igo Paulino, Amauri F. Medeiros, Hisao Takahashi, Cristiano M. Wrasse, and Delano Gobbi
Ann. Geophys., 36, 705–715, https://doi.org/10.5194/angeo-36-705-2018, https://doi.org/10.5194/angeo-36-705-2018, 2018
Rafael L. A. Mesquita, John W. Meriwether, Jonathan J. Makela, Daniel J. Fisher, Brian J. Harding, Samuel C. Sanders, Fasil Tesema, and Aaron J. Ridley
Ann. Geophys., 36, 541–553, https://doi.org/10.5194/angeo-36-541-2018, https://doi.org/10.5194/angeo-36-541-2018, 2018
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The midnight temperature maximum (MTM) is a phenomenon resulting from the constructive interference of the atmospheric tides. This paper brings the analysis of a long data set (846 nights) from the NATION network along with new analysis techniques (harmonic background removal and 2-D temperature interpolation) to detect the MTM in the mid-latitude range.
Amauri Fragoso Medeiros, Igo Paulino, Cristiano Max Wrasse, Joaquim Fechine, Hisao Takahashi, José Valentin Bageston, Ana Roberta Paulino, and Ricardo Arlen Buriti
Ann. Geophys., 36, 311–319, https://doi.org/10.5194/angeo-36-311-2018, https://doi.org/10.5194/angeo-36-311-2018, 2018
Short summary
Short summary
On 3 October 2005, a mesospheric front was observed over São João do Cariri (7.4° S, 36.5° W) propagating to the northeast in the OH airglow images. One and a half hours later, it disappeared completely and ripples were observed in the eastern part of the images. After studying the background atmosphere, the main conclusion of this work was that the instability in the airglow layer did not allow the propagation of the front to the other side of the local zenith.
Gabriel Augusto Giongo, José Valentin Bageston, Paulo Prado Batista, Cristiano Max Wrasse, Gabriela Dornelles Bittencourt, Igo Paulino, Neusa Maria Paes Leme, David C. Fritts, Diego Janches, Wayne Hocking, and Nelson Jorge Schuch
Ann. Geophys., 36, 253–264, https://doi.org/10.5194/angeo-36-253-2018, https://doi.org/10.5194/angeo-36-253-2018, 2018
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This work presents four events of mesosphere fronts observed on King George Island, Antarctic Peninsula, in the year 2011. The atmospheric background environment was analyzed to investigate the propagation conditions for all cases. To investigate the sources for such cases, satellite images were used. In two cases, we found that strong tropospheric instabilities were potential sources, and in the other two cases, it was not possible to associate them with tropospheric sources.
Fabio Egito, Ricardo Arlen Buriti, Amauri Fragoso Medeiros, and Hisao Takahashi
Ann. Geophys., 36, 231–241, https://doi.org/10.5194/angeo-36-231-2018, https://doi.org/10.5194/angeo-36-231-2018, 2018
Diego Barros, Hisao Takahashi, Cristiano M. Wrasse, and Cosme Alexandre O. B. Figueiredo
Ann. Geophys., 36, 91–100, https://doi.org/10.5194/angeo-36-91-2018, https://doi.org/10.5194/angeo-36-91-2018, 2018
Fabio Egito, Hisao Takahashi, and Yasunobu Miyoshi
Ann. Geophys., 35, 1023–1032, https://doi.org/10.5194/angeo-35-1023-2017, https://doi.org/10.5194/angeo-35-1023-2017, 2017
Cosme Alexandre O. B. Figueiredo, Ricardo A. Buriti, Igo Paulino, John W. Meriwether, Jonathan J. Makela, Inez S. Batista, Diego Barros, and Amauri F. Medeiros
Ann. Geophys., 35, 953–963, https://doi.org/10.5194/angeo-35-953-2017, https://doi.org/10.5194/angeo-35-953-2017, 2017
Fasil Tesema, Rafael Mesquita, John Meriwether, Baylie Damtie, Melessew Nigussie, Jonathan Makela, Daniel Fisher, Brian Harding, Endawoke Yizengaw, and Samuel Sanders
Ann. Geophys., 35, 333–344, https://doi.org/10.5194/angeo-35-333-2017, https://doi.org/10.5194/angeo-35-333-2017, 2017
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Measurements of equatorial thermospheric winds obtained from an optical instrument called a Fabry–Perot interferometer in Ethiopia show a significance difference as compared with other longitudinal sectors. The zonal wind in this sector is small and shows a gradual decrease through out the night. Application of climatological wind and temperature models shows good agreement with the observations over Ethiopia.
Mohamed Kaab, Zouhair Benkhaldoun, Daniel J. Fisher, Brian Harding, Aziza Bounhir, Jonathan J. Makela, Amine Laghriyeb, Khalifa Malki, Ahmed Daassou, and Mohamed Lazrek
Ann. Geophys., 35, 161–170, https://doi.org/10.5194/angeo-35-161-2017, https://doi.org/10.5194/angeo-35-161-2017, 2017
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we present the first multi-year results of the climatology of horizontal winds obtained during a period of 26 months. We compare the observed climatologies of neutral winds to that provided by the recently updated Horizontal Wind Model (HWM14) in order to validate that model's predictions of the thermospheric wind patterns over the eastern portion of Africa. HWM14 generally compares well with the horizontal winds, but significant magnitude and phase differences remain in certain seasons.
I. Paulino, A. F. Medeiros, S. L. Vadas, C. M. Wrasse, H. Takahashi, R. A. Buriti, D. Leite, S. Filgueira, J. V. Bageston, J. H. A. Sobral, and D. Gobbi
Ann. Geophys., 34, 293–301, https://doi.org/10.5194/angeo-34-293-2016, https://doi.org/10.5194/angeo-34-293-2016, 2016
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Periodic waves have been observed over São João do Cariri during almost one solar cycle. Similarities between the characteristics of these events with observations at other places around the world were noted, primarily the spectral parameters. Most observed waves have appeared during magnetically quiet nights, and the occurrence of those waves followed the solar activity. Due to their characteristics, most of them must have had different generation mechanisms from the Perkins instability.
A. F. Medeiros, I. Paulino, M. J. Taylor, J. Fechine, H. Takahashi, R. A. Buriti, L. M. Lima, and C. M. Wrasse
Ann. Geophys., 34, 91–96, https://doi.org/10.5194/angeo-34-91-2016, https://doi.org/10.5194/angeo-34-91-2016, 2016
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This paper reports two consecutive mesospheric bores observed in the airglow emissions (OH and OI5577). Both bores propagated to the east and showed similar spectral characteristics. However, the first one exhibited a dark leading front with several trailing waves behind and progressed into a brighter airglow region. However, the second bore, observed in the OH layer, was comprised of several bright waves propagating into a darker airglow region.
M. Sivakandan, I. Paulino, A. Taori, and K. Niranjan
Atmos. Meas. Tech., 9, 93–102, https://doi.org/10.5194/amt-9-93-2016, https://doi.org/10.5194/amt-9-93-2016, 2016
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The small-scale gravity waves are the least understood processes in the middle-atmospheric variability. Using airglow imaging, we provide new measurements of gravity wave propagation over equatorial latitudes in India. We find that propagation of waves is often in the opposite direction to the tropospheric convective regions. These waves are found to have horizontal wavelengths ranging from 12 to 42 km, with the phase velocities in the 20 to 90 km range.
E. S. Miller, H. Kil, J. J. Makela, R. A. Heelis, E. R. Talaat, and A. Gross
Ann. Geophys., 32, 959–965, https://doi.org/10.5194/angeo-32-959-2014, https://doi.org/10.5194/angeo-32-959-2014, 2014
T. M. Duly, N. P. Chapagain, and J. J. Makela
Ann. Geophys., 31, 2229–2237, https://doi.org/10.5194/angeo-31-2229-2013, https://doi.org/10.5194/angeo-31-2229-2013, 2013
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This article presents characteristics of periodic waves observed in the thermosphere from airglow images collected in the Northeast of Brazil. Using simultaneous measurements of the background wind in the airglow emission altitudes, it was possible to estimate the intrinsic parameters and the role of the wind in the propagation of the waves into the thermosphere. An anisotropy in the propagation direction of the waves was observed and it could be explained by the wind filtering process.
This article presents characteristics of periodic waves observed in the thermosphere from...
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