Articles | Volume 40, issue 1
https://doi.org/10.5194/angeo-40-1-2022
© Author(s) 2022. 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-40-1-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Regular paper
| 
04 Jan 2022
Regular paper |
| 04 Jan 2022
| 04 Jan 2022
Types of pulsating aurora: comparison of model and EISCAT electron density observations
Arctic Geophysics department, The University Centre in Svalbard (UNIS), Longyearbyen 9170, Norway
Birkeland Centre for Space Science, University of Bergen, 5007 Bergen, Norway
Noora Partamies
Arctic Geophysics department, The University Centre in Svalbard (UNIS), Longyearbyen 9170, Norway
Birkeland Centre for Space Science, University of Bergen, 5007 Bergen, Norway
Daniel K. Whiter
School of Physics and Astronomy, University of Southampton, Southampton, UK
Yasunobu Ogawa
National Institute of Polar Research, 90-8518 Tokyo, Japan
Related authors
Jonas Suni, Minna Palmroth, Lucile Turc, Markus Battarbee, Giulia Cozzani, Maxime Dubart, Urs Ganse, Harriet George, Evgeny Gordeev, Konstantinos Papadakis, Yann Pfau-Kempf, Vertti Tarvus, Fasil Tesema, and Hongyang Zhou
Ann. Geophys., 41, 551–568, https://doi.org/10.5194/angeo-41-551-2023, https://doi.org/10.5194/angeo-41-551-2023, 2023
Short summary
Short summary
Magnetosheath jets are structures of enhanced plasma density and/or velocity in a region of near-Earth space known as the magnetosheath. When they propagate towards the Earth, these jets can disturb the Earth's magnetic field and cause hazards for satellites. In this study, we use a simulation called Vlasiator to model near-Earth space and investigate jets using case studies and statistical analysis. We find that jets that propagate towards the Earth are different from jets that do not.
Markku Alho, Giulia Cozzani, Ivan Zaitsev, Fasil Tesema Kebede, Urs Ganse, Markus Battarbee, Maarja Bussov, Maxime Dubart, Sanni Hoilijoki, Leo Kotipalo, Konstantinos Papadakis, Yann Pfau-Kempf, Jonas Suni, Vertti Tarvus, Abiyot Workayehu, Hongyang Zhou, and Minna Palmroth
EGUsphere, https://doi.org/10.5194/egusphere-2023-2300, https://doi.org/10.5194/egusphere-2023-2300, 2023
Short summary
Short summary
In detailed space plasma simulations, finding and characterizing magnetic reconnection sites and related geometries requires new tools to describe complex and dynamic geometries. This paper addresses the problem by determining suitable local coordinate systems and finding the geometrical signatures of relevant magnetic field features in these coordinates. We demonstrate the utility of the method on a state-of-the-art 3D simulation of Earth's magnetosphere, performed with the Vlasiator code.
Konstantinos Papadakis, Yann Pfau-Kempf, Urs Ganse, Markus Battarbee, Markku Alho, Maxime Grandin, Maxime Dubart, Lucile Turc, Hongyang Zhou, Konstantinos Horaites, Ivan Zaitsev, Giulia Cozzani, Maarja Bussov, Evgeny Gordeev, Fasil Tesema, Harriet George, Jonas Suni, Vertti Tarvus, and Minna Palmroth
Geosci. Model Dev., 15, 7903–7912, https://doi.org/10.5194/gmd-15-7903-2022, https://doi.org/10.5194/gmd-15-7903-2022, 2022
Short summary
Short summary
Vlasiator is a plasma simulation code that simulates the entire near-Earth space at a global scale. As 6D simulations require enormous amounts of computational resources, Vlasiator uses adaptive mesh refinement (AMR) to lighten the computational burden. However, due to Vlasiator’s grid topology, AMR simulations suffer from grid aliasing artifacts that affect the global results. In this work, we present and evaluate the performance of a mechanism for alleviating those artifacts.
Noora Partamies, Fasil Tesema, Emma Bland, Erkka Heino, Hilde Nesse Tyssøy, and Erlend Kallelid
Ann. Geophys., 39, 69–83, https://doi.org/10.5194/angeo-39-69-2021, https://doi.org/10.5194/angeo-39-69-2021, 2021
Short summary
Short summary
About 200 nights of substorm activity have been analysed for their magnetic disturbance magnitude and the level of cosmic radio noise absorption. We show that substorms with a single expansion phase have limited lifetimes and spatial extents. Starting from magnetically quiet conditions, the strongest absorption occurs after 1 to 2 nights of substorm activity. This prolonged activity is thus required to accelerate particles to energies, which may affect the atmospheric chemistry.
Fasil Tesema, Noora Partamies, Hilde Nesse Tyssøy, and Derek McKay
Ann. Geophys., 38, 1191–1202, https://doi.org/10.5194/angeo-38-1191-2020, https://doi.org/10.5194/angeo-38-1191-2020, 2020
Short summary
Short summary
In this study, we present the ionization level from EISCAT radar experiments and cosmic noise absorption level
from KAIRA riometer observations during pulsating auroras. We found thick layers of ionization that reach down
to 70 km (harder precipitation) and higher cosmic noise absorption during patchy pulsating aurora than
during amorphous pulsating and patchy auroras.
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
Short summary
Short summary
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.
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
Short summary
Short summary
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.
Jonas Suni, Minna Palmroth, Lucile Turc, Markus Battarbee, Giulia Cozzani, Maxime Dubart, Urs Ganse, Harriet George, Evgeny Gordeev, Konstantinos Papadakis, Yann Pfau-Kempf, Vertti Tarvus, Fasil Tesema, and Hongyang Zhou
Ann. Geophys., 41, 551–568, https://doi.org/10.5194/angeo-41-551-2023, https://doi.org/10.5194/angeo-41-551-2023, 2023
Short summary
Short summary
Magnetosheath jets are structures of enhanced plasma density and/or velocity in a region of near-Earth space known as the magnetosheath. When they propagate towards the Earth, these jets can disturb the Earth's magnetic field and cause hazards for satellites. In this study, we use a simulation called Vlasiator to model near-Earth space and investigate jets using case studies and statistical analysis. We find that jets that propagate towards the Earth are different from jets that do not.
Yoshimasa Tanaka, Yasunobu Ogawa, Akira Kadokura, Takehiko Aso, Björn Gustavsson, Urban Brändström, Tima Sergienko, Genta Ueno, and Satoko Saita
Ann. Geophys. Discuss., https://doi.org/10.5194/angeo-2023-35, https://doi.org/10.5194/angeo-2023-35, 2023
Revised manuscript accepted for ANGEO
Short summary
Short summary
We present by simulation how useful monochromatic images taken by a multi-point imager network are for auroral research in the EISCAT_3D project. We apply the generalized-aurora computed tomography (G-ACT) method to modelled multiple auroral images and ionospheric electron density data. It is demonstrated that the G-ACT provides better reconstruction results than the normal ACT and can interpolate ionospheric electron density at a much higher spatial resolution than observed by EISCAT_3D radar.
Mizuki Fukizawa, Yoshimasa Tanaka, Yasunobu Ogawa, Keisuke Hosokawa, Tero Raita, and Kirsti Kauristie
Ann. Geophys., 41, 511–528, https://doi.org/10.5194/angeo-41-511-2023, https://doi.org/10.5194/angeo-41-511-2023, 2023
Short summary
Short summary
We use computed tomography to reconstruct the three-dimensional distributions of the Hall and Pedersen conductivities of pulsating auroras, a key research target for understanding the magnetosphere–ionosphere coupling process. It is suggested that the high-energy electron precipitation associated with pulsating auroras may have a greater impact on the closure of field-aligned currents in the ionosphere than has been previously reported.
Liisa Juusola, Ari Viljanen, Noora Partamies, Heikki Vanhamäki, Mirjam Kellinsalmi, and Simon Walker
Ann. Geophys., 41, 483–510, https://doi.org/10.5194/angeo-41-483-2023, https://doi.org/10.5194/angeo-41-483-2023, 2023
Short summary
Short summary
At times when auroras erupt on the sky, the magnetic field surrounding the Earth undergoes rapid changes. On the ground, these changes can induce harmful electric currents in technological conductor networks, such as powerlines. We have used magnetic field observations from northern Europe during 28 such events and found consistent behavior that can help to understand, and thus predict, the processes that drive auroras and geomagnetically induced currents.
Markku Alho, Giulia Cozzani, Ivan Zaitsev, Fasil Tesema Kebede, Urs Ganse, Markus Battarbee, Maarja Bussov, Maxime Dubart, Sanni Hoilijoki, Leo Kotipalo, Konstantinos Papadakis, Yann Pfau-Kempf, Jonas Suni, Vertti Tarvus, Abiyot Workayehu, Hongyang Zhou, and Minna Palmroth
EGUsphere, https://doi.org/10.5194/egusphere-2023-2300, https://doi.org/10.5194/egusphere-2023-2300, 2023
Short summary
Short summary
In detailed space plasma simulations, finding and characterizing magnetic reconnection sites and related geometries requires new tools to describe complex and dynamic geometries. This paper addresses the problem by determining suitable local coordinate systems and finding the geometrical signatures of relevant magnetic field features in these coordinates. We demonstrate the utility of the method on a state-of-the-art 3D simulation of Earth's magnetosphere, performed with the Vlasiator code.
Tinna Lif Gunnarsdottir, Ingrid Mann, Wuhu Feng, Devin R. Huyghebaert, Ingemar Haeggstroem, Yasunobu Ogawa, Norihito Saito, Satonori Nozawa, and Takuya D. Kawahara
Ann. Geophys. Discuss., https://doi.org/10.5194/angeo-2023-29, https://doi.org/10.5194/angeo-2023-29, 2023
Preprint under review for ANGEO
Short summary
Short summary
Several tons of meteoric particles burn up in our atmosphere each day. This deposits a great deal of material that bids 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.
Anton Goertz, Noora Partamies, Daniel Whiter, and Lisa Baddeley
Ann. Geophys., 41, 115–128, https://doi.org/10.5194/angeo-41-115-2023, https://doi.org/10.5194/angeo-41-115-2023, 2023
Short summary
Short summary
Poleward moving auroral forms (PMAFs) are specific types of aurora believed to be the signature of the connection of Earth's magnetic field to that of the sun. In this paper, we discuss the evolution of PMAFs with regard to their auroral morphology as observed in all-sky camera images. We interpret different aspects of this evolution in terms of the connection dynamics between the magnetic fields of Earth and the sun. This sheds more light on the magnetic interaction between the sun and Earth.
Daniel K. Whiter, Noora Partamies, Björn Gustavsson, and Kirsti Kauristie
Ann. Geophys., 41, 1–12, https://doi.org/10.5194/angeo-41-1-2023, https://doi.org/10.5194/angeo-41-1-2023, 2023
Short summary
Short summary
We measured the height of green and blue aurorae using thousands of camera images recorded over a 7-year period. Both colours are typically brightest at about 114 km altitude. When they peak at higher altitudes the blue aurora is usually higher than the green aurora. This information will help other studies which need an estimate of the auroral height. We used a computer model to explain our observations and to investigate how the green aurora is produced.
Konstantinos Papadakis, Yann Pfau-Kempf, Urs Ganse, Markus Battarbee, Markku Alho, Maxime Grandin, Maxime Dubart, Lucile Turc, Hongyang Zhou, Konstantinos Horaites, Ivan Zaitsev, Giulia Cozzani, Maarja Bussov, Evgeny Gordeev, Fasil Tesema, Harriet George, Jonas Suni, Vertti Tarvus, and Minna Palmroth
Geosci. Model Dev., 15, 7903–7912, https://doi.org/10.5194/gmd-15-7903-2022, https://doi.org/10.5194/gmd-15-7903-2022, 2022
Short summary
Short summary
Vlasiator is a plasma simulation code that simulates the entire near-Earth space at a global scale. As 6D simulations require enormous amounts of computational resources, Vlasiator uses adaptive mesh refinement (AMR) to lighten the computational burden. However, due to Vlasiator’s grid topology, AMR simulations suffer from grid aliasing artifacts that affect the global results. In this work, we present and evaluate the performance of a mechanism for alleviating those artifacts.
Noora Partamies, Daniel Whiter, Kirsti Kauristie, and Stefano Massetti
Ann. Geophys., 40, 605–618, https://doi.org/10.5194/angeo-40-605-2022, https://doi.org/10.5194/angeo-40-605-2022, 2022
Short summary
Short summary
We investigate the local time behaviour of auroral structures and emission height. Data are collected from the Fennoscandian Lapland and Svalbard latitutes from 7 identical auroral all-sky cameras over about 1 solar cycle. The typical peak emission height of the green aurora varies from 110 km on the nightside to about 118 km in the morning over Lapland but stays systematically higher over Svalbard. During fast solar wind, nightside emission heights are 5 km lower than during slow solar wind.
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.
Derek McKay, Juha Vierinen, Antti Kero, and Noora Partamies
Geosci. Instrum. Method. Data Syst., 11, 25–35, https://doi.org/10.5194/gi-11-25-2022, https://doi.org/10.5194/gi-11-25-2022, 2022
Short summary
Short summary
When radio waves from our galaxy enter the Earth's atmosphere, they are absorbed by electrons in the upper atmosphere. It was thought that by measuring the amount of absorption, it would allow the height of these electrons in the atmosphere to be determined. If so, this would have significance for future instrument design. However, this paper demonstrates that it is not possible to do this, but it does explain how multiple-frequency measurements can nevertheless be useful.
Daniel K. Whiter, Hanna Sundberg, Betty S. Lanchester, Joshua Dreyer, Noora Partamies, Nickolay Ivchenko, Marco Zaccaria Di Fraia, Rosie Oliver, Amanda Serpell-Stevens, Tiffany Shaw-Diaz, and Thomas Braunersreuther
Ann. Geophys., 39, 975–989, https://doi.org/10.5194/angeo-39-975-2021, https://doi.org/10.5194/angeo-39-975-2021, 2021
Short summary
Short summary
This paper presents an analysis of high-resolution optical and radar observations of a phenomenon called fragmented aurora-like emissions (FAEs) observed close to aurora in the high Arctic. The observations suggest that FAEs are not caused by high-energy electrons or protons entering the atmosphere along Earth's magnetic field and are, therefore, not aurora. The speeds of the FAEs and their internal dynamics were measured and used to evaluate theories for how the FAEs are produced.
Florine Enengl, Noora Partamies, Nickolay Ivchenko, and Lisa Baddeley
Ann. Geophys., 39, 795–809, https://doi.org/10.5194/angeo-39-795-2021, https://doi.org/10.5194/angeo-39-795-2021, 2021
Short summary
Short summary
Energetic particle precipitation has the potential to change the neutral atmospheric temperature at the bottom of the ionosphere. We have searched for events and investigated a possible correlation between lower-ionosphere electron density enhancements and simultaneous neutral temperature changes. Six of the 10 analysed events are associated with a temperature decrease of 10–20K. The events change the chemical composition in the mesosphere, and the temperatures are probed at lower altitudes.
Joshua Dreyer, Noora Partamies, Daniel Whiter, Pål G. Ellingsen, Lisa Baddeley, and Stephan C. Buchert
Ann. Geophys., 39, 277–288, https://doi.org/10.5194/angeo-39-277-2021, https://doi.org/10.5194/angeo-39-277-2021, 2021
Short summary
Short summary
Small-scale auroral features are still being discovered and are not well understood. Where aurorae are caused by particle precipitation, the newly reported fragmented aurora-like emissions (FAEs) seem to be locally generated in the ionosphere (hence,
aurora-like). We analyse data from multiple instruments located near Longyearbyen to derive their main characteristics. They seem to occur as two types in a narrow altitude region (individually or in regularly spaced groups).
Noora Partamies, Fasil Tesema, Emma Bland, Erkka Heino, Hilde Nesse Tyssøy, and Erlend Kallelid
Ann. Geophys., 39, 69–83, https://doi.org/10.5194/angeo-39-69-2021, https://doi.org/10.5194/angeo-39-69-2021, 2021
Short summary
Short summary
About 200 nights of substorm activity have been analysed for their magnetic disturbance magnitude and the level of cosmic radio noise absorption. We show that substorms with a single expansion phase have limited lifetimes and spatial extents. Starting from magnetically quiet conditions, the strongest absorption occurs after 1 to 2 nights of substorm activity. This prolonged activity is thus required to accelerate particles to energies, which may affect the atmospheric chemistry.
Fasil Tesema, Noora Partamies, Hilde Nesse Tyssøy, and Derek McKay
Ann. Geophys., 38, 1191–1202, https://doi.org/10.5194/angeo-38-1191-2020, https://doi.org/10.5194/angeo-38-1191-2020, 2020
Short summary
Short summary
In this study, we present the ionization level from EISCAT radar experiments and cosmic noise absorption level
from KAIRA riometer observations during pulsating auroras. We found thick layers of ionization that reach down
to 70 km (harder precipitation) and higher cosmic noise absorption during patchy pulsating aurora than
during amorphous pulsating and patchy auroras.
Sam Tuttle, Betty Lanchester, Björn Gustavsson, Daniel Whiter, Nickolay Ivchenko, Robert Fear, and Mark Lester
Ann. Geophys., 38, 845–859, https://doi.org/10.5194/angeo-38-845-2020, https://doi.org/10.5194/angeo-38-845-2020, 2020
Short summary
Short summary
Electric fields in the atmosphere near dynamic aurora are important in the physics of the electric circuit within the Earth's magnetic field. Oxygen ions emit light as they move under the influence of these electric fields; the flow of this emission is used to find the electric field at high temporal resolution. The solution needs two other simultaneous measurements of auroral emissions to give key parameters such as the auroral energy. The electric fields increase with brightness of the aurora.
Joshua M. Chadney and Daniel K. Whiter
Geosci. Instrum. Method. Data Syst., 7, 317–329, https://doi.org/10.5194/gi-7-317-2018, https://doi.org/10.5194/gi-7-317-2018, 2018
Short summary
Short summary
We measure spectra of upper atmospheric emissions in optical wavelengths using the High Throughput Imaging Echelle Spectrograph (HiTIES) located on Svalbard. These spectra contain superposed emissions originating from different altitudes. In this paper, we describe a fitting method which allows us to separate the measured emissions, thus allowing us to measure neutral temperatures at different altitudes and the density of water vapour in the atmosphere above the instrument.
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
Short summary
Short summary
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.
Nickolay Ivchenko, Nicola M. Schlatter, Hanna Dahlgren, Yasunobu Ogawa, Yuka Sato, and Ingemar Häggström
Ann. Geophys., 35, 1143–1149, https://doi.org/10.5194/angeo-35-1143-2017, https://doi.org/10.5194/angeo-35-1143-2017, 2017
Short summary
Short summary
Photo-electrons and secondary electrons from particle precipitation enhance the incoherent scatter plasma line to levels sufficient for detection. A plasma line gives an accurate measure of the electron density and can be used to estimate electron temperature. The occurrence of plasma line enhancements in the EISCAT Svalbard Radar data was investigated. During summer daytime hours the plasma line is detectable in up to 90 % of the data. In winter time the occurrence is a few percent.
Hanna Dahlgren, Betty S. Lanchester, Nickolay Ivchenko, and Daniel K. Whiter
Ann. Geophys., 35, 493–503, https://doi.org/10.5194/angeo-35-493-2017, https://doi.org/10.5194/angeo-35-493-2017, 2017
Short summary
Short summary
Pulsating aurora are ubiquitous events that constitute a large amount of energy transfer to the ionosphere. Still there are unsolved issues regarding their formation. Using high-resolution optical and radar data, we find that it is the flux of high-energy electrons that get reduced during the OFF period of the pulsations. We also report on dips in brightness at the transition between ON and OFF, and asymmetric rise and fall times, which may have implications for understanding the pulsations.
Joshua M. Chadney, Daniel K. Whiter, and Betty S. Lanchester
Ann. Geophys., 35, 481–491, https://doi.org/10.5194/angeo-35-481-2017, https://doi.org/10.5194/angeo-35-481-2017, 2017
Short summary
Short summary
A layer of excited OH molecules in the upper atmosphere produces strong airglow emission from which it is possible to obtain the temperature of the layer. To obtain accurate temperatures values, one must take into account the absorption of OH emission by water vapour in the lower atmosphere before this emission is measured by instruments on the ground. This paper provides the amount of absorption suffered by each OH line due to water vapour and presents a method to estimate water concentrations.
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
Short summary
Short summary
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.
Tuomas Savolainen, Daniel Keith Whiter, and Noora Partamies
Geosci. Instrum. Method. Data Syst., 5, 305–314, https://doi.org/10.5194/gi-5-305-2016, https://doi.org/10.5194/gi-5-305-2016, 2016
Short summary
Short summary
In this paper we describe a new method for recognition of digits in seven-segment displays. The method is used for adding date and time information to a dataset consisting of about 7 million auroral all-sky images taken during the time period of 1973–1997 at camera stations centred around Sodankylä observatory in Northern Finland. In each image there is a clock display for the date and time together with the reflection of the whole night sky through a spherical mirror.
T. Takahashi, S. Nozawa, T. T. Tsuda, Y. Ogawa, N. Saito, T. Hidemori, T. D. Kawahara, C. Hall, H. Fujiwara, N. Matuura, A. Brekke, M. Tsutsumi, S. Wada, T. Kawabata, S. Oyama, and R. Fujii
Ann. Geophys., 33, 941–953, https://doi.org/10.5194/angeo-33-941-2015, https://doi.org/10.5194/angeo-33-941-2015, 2015
N. M. Schlatter, V. Belyey, B. Gustavsson, N. Ivchenko, D. Whiter, H. Dahlgren, S. Tuttle, and T. Grydeland
Ann. Geophys., 33, 837–844, https://doi.org/10.5194/angeo-33-837-2015, https://doi.org/10.5194/angeo-33-837-2015, 2015
Short summary
Short summary
The high-latitude ionosphere is a dynamic region where particle precipitation leads to various phenomena including wave instability and turbulence. Anomalous echoes related to aurora are observed in ground-based radar observations of the ionosphere. These echoes indicate enhanced ion acoustic fluctuations. In this article, we show that the origin of the echo is located in or close to the region of particle precipitation and that the echo region itself is limited to hundreds of meters.
T. Ishida, Y. Ogawa, A. Kadokura, K. Hosokawa, and Y. Otsuka
Ann. Geophys., 33, 525–530, https://doi.org/10.5194/angeo-33-525-2015, https://doi.org/10.5194/angeo-33-525-2015, 2015
Short summary
Short summary
We studied the localized plasma density enhancements called blobs, which are often produced in the high-latitude ionosphere by the transportation process of plasma or particle precipitations. This subject is important because such structures affect radio wave propagation and can cause scintillation of GNSS signals in the deformation process. This paper is the first report of direct observations of blob deformation during a substorm.
H. Fujiwara, S. Nozawa, Y. Ogawa, R. Kataoka, Y. Miyoshi, H. Jin, and H. Shinagawa
Ann. Geophys., 32, 831–839, https://doi.org/10.5194/angeo-32-831-2014, https://doi.org/10.5194/angeo-32-831-2014, 2014
D. K. Whiter, B. Gustavsson, N. Partamies, and L. Sangalli
Geosci. Instrum. Method. Data Syst., 2, 131–144, https://doi.org/10.5194/gi-2-131-2013, https://doi.org/10.5194/gi-2-131-2013, 2013
Related subject area
Subject: Earth's ionosphere & aeronomy | Keywords: Particle precipitation
On the relationship of energetic particle precipitation and mesopause temperature
D-region impact area of energetic electron precipitation during pulsating aurora
Electron precipitation characteristics during isolated, compound, and multi-night substorm events
Florine Enengl, Noora Partamies, Nickolay Ivchenko, and Lisa Baddeley
Ann. Geophys., 39, 795–809, https://doi.org/10.5194/angeo-39-795-2021, https://doi.org/10.5194/angeo-39-795-2021, 2021
Short summary
Short summary
Energetic particle precipitation has the potential to change the neutral atmospheric temperature at the bottom of the ionosphere. We have searched for events and investigated a possible correlation between lower-ionosphere electron density enhancements and simultaneous neutral temperature changes. Six of the 10 analysed events are associated with a temperature decrease of 10–20K. The events change the chemical composition in the mesosphere, and the temperatures are probed at lower altitudes.
Emma Bland, Fasil Tesema, and Noora Partamies
Ann. Geophys., 39, 135–149, https://doi.org/10.5194/angeo-39-135-2021, https://doi.org/10.5194/angeo-39-135-2021, 2021
Short summary
Short summary
A total of 10 Super Dual Auroral Radar Network radars were used to estimate the horizontal area over which energetic electrons impact the atmosphere at 70–100 km altitude during pulsating aurorae (PsAs). The impact area varies significantly from event to event. Approximately one-third extend over 12° of magnetic latitude, while others are highly localised. Our results could be used to improve the forcing used in atmospheric/climate models to properly capture the energy contribution from PsAs.
Noora Partamies, Fasil Tesema, Emma Bland, Erkka Heino, Hilde Nesse Tyssøy, and Erlend Kallelid
Ann. Geophys., 39, 69–83, https://doi.org/10.5194/angeo-39-69-2021, https://doi.org/10.5194/angeo-39-69-2021, 2021
Short summary
Short summary
About 200 nights of substorm activity have been analysed for their magnetic disturbance magnitude and the level of cosmic radio noise absorption. We show that substorms with a single expansion phase have limited lifetimes and spatial extents. Starting from magnetically quiet conditions, the strongest absorption occurs after 1 to 2 nights of substorm activity. This prolonged activity is thus required to accelerate particles to energies, which may affect the atmospheric chemistry.
Cited articles
Berkey, F.: Observations of pulsating aurora in the day sector auroral zone,
Planet. Space Sci., 26, 635–650,
https://doi.org/10.1016/0032-0633(78)90097-1, 1978. a
Bland, E. C., Partamies, N., Heino, E., Yukimatu, A. S., and Miyaoka, H.:
Energetic Electron Precipitation Occurrence Rates Determined Using the Syowa
East SuperDARN Radar, J. Geophys. Res.-Space, 124,
6253–6265, https://doi.org/10.1029/2018ja026437, 2019. a, b
Fukizawa, M., Sakanoi, T., Miyoshi, Y., Hosokawa, K., Shiokawa, K., Katoh, Y.,
Kazama, Y., Kumamoto, A., Tsuchiya, F., Miyashita, Y., Tanaka, Y. Â.,
Kasahara, Y., Ozaki, M., Matsuoka, A., Matsuda, S., Hikishima, M., Oyama, S.,
Ogawa, Y., Kurita, S., and Fujii, R.: Electrostatic Electron Cyclotron
Harmonic Waves as a Candidate to Cause Pulsating Auroras, Geophys.
Res. Lett., 45, 661–12, https://doi.org/10.1029/2018GL080145, 2018. a
Grono, E. and Donovan, E.: Differentiating diffuse auroras based on phenomenology, Ann. Geophys., 36, 891–898, https://doi.org/10.5194/angeo-36-891-2018, 2018. a, b, c
Grono, E., Donovan, E., and Murphy, K. R.: Tracking patchy pulsating aurora
through all-sky images, Ann. Geophys., 35, 777–784,
https://doi.org/10.5194/angeo-35-777-2017, 2017. a
Hosokawa, K. and Ogawa, P.: Ionospheric
variation during pulsating aurora, J. Geophys. Res.-Space, 120, 5943–5957,
https://doi.org/10.1002/2015JA021401, 2015. a, b
Jones, S. L., Lessard, M. R., Fernandes, P. A., Lummerzheim, D., Semeter,
J. L., Heinselman, C. J., Lynch, K. A., Michell, R. G., Kintner, P. M.,
Stenbaek-Nielsen, H. C., and Asamura, K.: PFISR and ROPA observations of
pulsating aurora, J. Atmos. Sol.-Terr. Phys., 71,
708–716, https://doi.org/10.1016/j.jastp.2008.10.004, 2009. a
Jones, S. L., Lessard, M. R., Rychert, K., Spanswick, E., and Donovan, E.:
Large-scale aspects and temporal evolution of pulsating aurora, J.
Geophys. Res.-Space, 116, 1–7, https://doi.org/10.1029/2010JA015840,
2011. a
Kasahara, S., Miyoshi, Y., Yokota, S., Mitani, T., Kasahara, Y., Matsuda, S.,
Kumamoto, A., Matsuoka, A., Kazama, Y., Frey, H. U., Angelopoulos, V.,
Kurita, S., Keika, K., Seki, K., and Shinohara, I.: Pulsating aurora from
electron scattering by chorus waves, Nature, 554, 337–340,
https://doi.org/10.1038/nature25505, 2018. a
Lanchester, B. S., Rees, M. H., Lummerzheim, D., Otto, A.,
Sedgemore-Schulthess, K. J. F., Zhu, H., and McCrea, I. W.: Ohmic heating as
evidence for strong field-aligned currents in filamentary aurora, J.
Geophys. Res., 106, 1785, https://doi.org/10.1029/1999JA000292, 2001. a
Lessard, M. R.: A Review of Pulsating Aurora, Geophys. Monogr. Ser., 197, 55–68,
https://doi.org/10.1029/2011GM001187, 2012. a
Lummerzheim, D. and Lilensten, J.: Electron transport and energy degradation in the ionosphere: evaluation of the numerical solution, comparison with laboratory experiments and auroral observations, Ann. Geophys., 12, 1039–1051, https://doi.org/10.1007/s00585-994-1039-7, 1994. a
McEwen, D. J., Yee, E., Whalen, B. A., and Yau, A. W.: Electron energy
measurements in pulsating auroras, Can. J. Phys., 59,
1106–1115, https://doi.org/10.1139/p81-146, 1981. a, b
McKay, D., Partamies, N., and Vierinen, J.: Pulsating aurora and cosmic noise
absorption associated with growth-phase arcs, Ann. Geophys., 36,
59–69, https://doi.org/10.5194/angeo-36-59-2018, 2018. a
Miyoshi, Y., Katoh, Y., Nishiyama, T., Sakanoi, T., Asamura, K., and Hirahara,
M.: Time of flight analysis of pulsating aurora electrons, considering
wave-particle interactions with propagating whistler mode waves, J.
Geophys. Res.-Space, 115, 1–7, https://doi.org/10.1029/2009JA015127,
2010. a
Miyoshi, Y., Oyama, S., Saito, S., Kurita, S., Fujiwara, H., Kataoka, R.,
Ebihara, Y., Kletzing, C., Reeves, G., Santolik, O., Clilverd, M., Rodger,
C. J., Turunen, E., and Tsuchiya, F.: Energetic electron precipitation
associated with pulsating aurora: EISCAT and Van Allen Probe observations,
J. Geophys. Res.-Space, 120, 2754–2766,
https://doi.org/10.1002/2014JA020690, 2015. a, b
Miyoshi, Y., Saito, S., Kurita, S., Asamura, K., Hosokawa, K., Sakanoi, T.,
Mitani, T., Ogawa, Y., Oyama, S., Tsuchiya, F., Jones, S. L., Jaynes, A. N.,
and Blake, J. B.: Relativistic Electron Microbursts as High Energy Tail of
Pulsating Aurora Electrons, Geophys. Res. Lett., 47, e2020GL090360,
https://doi.org/10.1029/2020gl090360, 2020. a, b
Nesse Tyssøy, H., Sandanger, M. I., Ødegaard, L.-K. G., Stadsnes, J.,
Aasnes, A., and Zawedde, A. E.: Energetic electron precipitation into the
middle atmosphere-Constructing the loss cone fluxes from MEPED POES, J. Geophys. Res.-Space, 121, 5693–5707,
https://doi.org/10.1002/2016JA022752, 2016. a
Nishimura, Y., Bortnik, J., Li, W., Thorne, R. M., Lyons, L. R., Angelopoulos,
V., Mende, S. B., Bonnell, J. W., Le Contel, O., Cully, C., Ergun, R., and
Auster, U.: Identifying the driver of pulsating aurora, Science,
330, 81–84, https://doi.org/10.1126/science.1193186, 2010. a, b
Nishimura, Y., Lessard, M. R., Katoh, Y., Miyoshi, Y., Grono, E., Partamies,
N., Sivadas, N., Hosokawa, K., Fukizawa, M., Samara, M., Michell, R. G.,
Kataoka, R., Sakanoi, T., Whiter, D. K., Oyama, S. i., Ogawa, Y., Kurita, S.,
ichiro Oyama, S., Ogawa, Y., and Kurita, S.: Diffuse and Pulsating Aurora, Space Sci. Rev., 216, 4,
https://doi.org/10.1007/s11214-019-0629-3, 2020. a, b, c, d
Ogawa, Y., Tanaka, Y., Kadokura, A., Hosokawa, K., Ebihara, Y., Motoba, T.,
Gustavsson, B., Brändström, U., Sato, Y., Oyama, S., Ozaki, M.,
Raita, T., Sigernes, F., Nozawa, S., Shiokawa, K., Kosch, M., Kauristie, K.,
Hall, C., Suzuki, S., Miyoshi, Y., Gerrard, A., Miyaoka, H., and Fujii, R.:
Development of low-cost multi-wavelength imager system for studies of aurora
and airglow, Polar Sci., 23, 100501, https://doi.org/10.1016/j.polar.2019.100501,
2020. a
Oguti, T., Kokubun, S., Hayashi, K., Tsuruda, K., Machida, S., Kitamura, T.,
Saka, O., and Watanabe, T.: Statistics of pulsating auroras on the basis of
all-sky TV data from five stations. I. Occurrence frequency, Can.
J. Phys., 59, 1150–1157, https://doi.org/10.1139/p81-152, 1981. a, b, c
Palmer, J.: Plasma density variations in the aurora, PhD thesis, University of Southampton, Southampton,
UK, 1995. a
Partamies, N., Whiter, D., Kadokura, A., Kauristie, K., Nesse Tyssøy, H.,
Massetti, S., Stauning, P., and Raita, T.: Occurrence and average behavior
of pulsating aurora, J. Geophys. Res.-Space, 122,
5606–5618, https://doi.org/10.1002/2017JA024039, 2017.
a, b
Partamies, N., Bolmgren, K., Heino, E., Ivchenko, N., Borovsky, J. E., and
Sundberg, H.: Patch Size Evolution During Pulsating Aurora, J.
Geophys. Res.-Space, 124, 4725–4738,
https://doi.org/10.1029/2018JA026423, 2019. a
Royrvik, O. and Davis, T. N.: Pulsating aurora: Local and global morphology,
J. Geophys. Res., 82, 4720–4740,
https://doi.org/10.1029/ja082i029p04720, 1977. a
Tesema, F., Partamies, N., Tyssøy, H. N., and McKay, D.: Observations of
precipitation energies during different types of pulsating aurora, Ann.
Geophys., 38, 1191–1202, https://doi.org/10.5194/angeo-38-1191-2020,
2020b. a, b, c, d
Turunen, E., Verronen, P. T., Seppälä, A., Rodger, C. J., Clilverd,
M. A., Tamminen, J., Enell, C. F., and Ulich, T.: Impact of different
energies of precipitating particles on NOx generation in the middle and upper
atmosphere during geomagnetic storms, J. Atmos.
Sol.-Terr. Phys., 71, 1176–1189, https://doi.org/10.1016/j.jastp.2008.07.005,
2009. a, b
Turunen, E., Kero, A., Verronen, P. T., Miyoshi, Y., Oyama, S. I., and Saito,
S.: Mesospheric ozone destruction by high-energy electron precipitation
associated with pulsating aurora, J. Geophys. Res., 121,
11852–11861, https://doi.org/10.1002/2016JD025015, 2016. a
Yamamoto, T.: On the temporal fluctuations of pulsating auroral luminosity,
J. Geophys. Res., 93, 897–911, https://doi.org/10.1029/JA093iA02p00897, 1988. a
Yang, B., Spanswick, E., Liang, J., Grono, E., and Donovan, E.: Responses of
Different Types of Pulsating Aurora in Cosmic Noise Absorption, Geophys.
Res. Lett., 46, 5717–5724, https://doi.org/10.1029/2019GL083289, 2019. a
Short summary
In this study, we present the comparison between an auroral model and EISCAT radar electron densities during pulsating aurorae. We test whether an overpassing satellite measurement of the average energy spectrum is a reasonable estimate for pulsating aurora electron precipitation. When patchy pulsating aurora is dominant in the morning sector, the overpass-averaged spectrum is found to be a reasonable estimate – but not when there is a mix of pulsating aurora types in the post-midnight sector.
In this study, we present the comparison between an auroral model and EISCAT radar electron...
