Articles | Volume 42, issue 1
https://doi.org/10.5194/angeo-42-145-2024
© Author(s) 2024. 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-42-145-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Regular paper
| 
16 May 2024
Regular paper |
| 16 May 2024
| 16 May 2024
Finding reconnection lines and flux rope axes via local coordinates in global ion-kinetic magnetospheric simulations
Department of Physics, University of Helsinki, Helsinki, Finland
Giulia Cozzani
Department of Physics, University of Helsinki, Helsinki, Finland
Ivan Zaitsev
Department of Physics, University of Helsinki, Helsinki, Finland
Fasil Tesema Kebede
Department of Physics, University of Helsinki, Helsinki, Finland
Urs Ganse
Department of Physics, University of Helsinki, Helsinki, Finland
Markus Battarbee
Department of Physics, University of Helsinki, Helsinki, Finland
Maarja Bussov
Department of Physics, University of Helsinki, Helsinki, Finland
Maxime Dubart
Department of Physics, University of Helsinki, Helsinki, Finland
Sanni Hoilijoki
Department of Physics, University of Helsinki, Helsinki, Finland
Leo Kotipalo
Department of Physics, University of Helsinki, Helsinki, Finland
Konstantinos Papadakis
Department of Physics, University of Helsinki, Helsinki, Finland
Yann Pfau-Kempf
Department of Physics, University of Helsinki, Helsinki, Finland
Jonas Suni
Department of Physics, University of Helsinki, Helsinki, Finland
Vertti Tarvus
Department of Physics, University of Helsinki, Helsinki, Finland
Abiyot Workayehu
Department of Physics, University of Helsinki, Helsinki, Finland
Hongyang Zhou
Department of Astronomy, Boston University, Boston, MA, USA
Minna Palmroth
Department of Physics, University of Helsinki, Helsinki, Finland
Finnish Meteorological Institute, Helsinki, Finland
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Yann Pfau-Kempf, Konstantinos Papadakis, Markku Alho, Markus Battarbee, Giulia Cozzani, Lauri Pänkäläinen, Urs Ganse, Fasil Kebede, Jonas Suni, Konstantinos Horaites, Maxime Grandin, and Minna Palmroth
Ann. Geophys., 43, 469–488, https://doi.org/10.5194/angeo-43-469-2025, https://doi.org/10.5194/angeo-43-469-2025, 2025
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Flux ropes are peculiar structures of twisted magnetic field occurring in many regions of space, near Earth and other planets, at the Sun, and in astrophysical objects. We developed a new way of detecting flux ropes in large supercomputer simulations of near-Earth space, and we use it to follow the evolution of flux ropes for long distances past the Earth in the flow direction. This will be useful in future studies as these flux ropes are involved in the transport of matter and energy in space.
Abiyot Bires Workayehu, Minna Palmroth, Maxime Grandin, Liisa Juusola, Markku Alho, Ivan Zaitsev, Venla Koikkalainen, Konstantinos Horaites, Yann Pfau-Kempf, Urs Ganse, Markus Battarbee, and Jonas Suni
EGUsphere, https://doi.org/10.5194/egusphere-2025-2282, https://doi.org/10.5194/egusphere-2025-2282, 2025
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We investigate the ionospheric signatures of BBFs in the magnetotail utilising a global 6D hybrid-Vlasov simulation coupled with an ionospheric model. We analyse changes in the magnitudes of ionospheric observables and use them as the ionospheric manifestations of bursty bulk flows. Our results reveal that reconnection-driven BBF induce vortices that generate FACs, which map to the ionosphere with distinct east-west alignment and exhibit a characteristic westward drift.
Venla Koikkalainen, Maxime Grandin, Emilia Kilpua, Abiyot Workayehu, Ivan Zaitsev, Liisa Juusola, Shi Tao, Markku Alho, Lauri Pänkäläinen, Giulia Cozzani, Konstantinos Horaites, Jonas Suni, Yann Pfau-Kempf, Urs Ganse, and Minna Palmroth
EGUsphere, https://doi.org/10.5194/egusphere-2025-2265, https://doi.org/10.5194/egusphere-2025-2265, 2025
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We use a numerical simulation to study phenomena that occur between the Earth’s dipolar magnetic field and the nightside of near-Earth space. We observe the formation of large-scale vortex flows with scales of several Earth radii. On the ionospheric grid of the simulation we find that the field-aligned currents formed in the simulation reflect the vortex flow in the transition region. The main finding is that the vortex flow is a result of a combination of flow dynamics and a plasma instability.
Shi Tao, Markku Alho, Ivan Zaitsev, Lucile Turc, Markus Battarbee, Urs Ganse, Yann Pfau-Kempf, and Minna Palmroth
EGUsphere, https://doi.org/10.5194/egusphere-2025-1340, https://doi.org/10.5194/egusphere-2025-1340, 2025
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Plasma convection is the movement of plasma that drags the magnetic field lines with it. Magnetic field in the solar wind interacts with the Earth's magnetic field and drags the dayside field lines of the Earth's magnetosphere toward nightside, causing the plasma inside the magnetosphere to circulate around the Earth in a process called the Dungey Cycle. Our simulation and methodology desribe this cycle in detail and find features in the convection that are not explained by fluid models.
Tuomas Häkkilä, Maxime Grandin, Markus Battarbee, Monika E. Szeląg, Markku Alho, Leo Kotipalo, Niilo Kalakoski, Pekka T. Verronen, and Minna Palmroth
Ann. Geophys., 43, 217–240, https://doi.org/10.5194/angeo-43-217-2025, https://doi.org/10.5194/angeo-43-217-2025, 2025
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Short summary
We study the atmospheric impact of auroral electron precipitation through the novel combination of both magnetospheric modelling and atmospheric modelling. We first simulate fluxes of auroral electrons and then use these fluxes to model their atmospheric impact. We find an increase of more than 200 % in thermospheric odd nitrogen and a corresponding decrease in stratospheric ozone of around 0.8 %. The produced auroral electron precipitation is realistic and shows potential for future studies.
Urs Ganse, Yann Pfau-Kempf, Hongyang Zhou, Liisa Juusola, Abiyot Workayehu, Fasil Kebede, Konstantinos Papadakis, Maxime Grandin, Markku Alho, Markus Battarbee, Maxime Dubart, Leo Kotipalo, Arnaud Lalagüe, Jonas Suni, Konstantinos Horaites, and Minna Palmroth
Geosci. Model Dev., 18, 511–527, https://doi.org/10.5194/gmd-18-511-2025, https://doi.org/10.5194/gmd-18-511-2025, 2025
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Vlasiator is a kinetic space plasma model that simulates the behavior of plasma, solar wind and magnetic fields in near-Earth space. So far, these simulations have been run without any interaction with the ionosphere, the uppermost layer of Earth's atmosphere. In this paper, we present the new methods that add an ionospheric electrodynamics model to Vlasiator, coupling it with the existing methods and presenting new simulation results of how space plasma and Earth's ionosphere interact.
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.
Vertti Tarvus, Lucile Turc, Markus Battarbee, Jonas Suni, Xóchitl Blanco-Cano, Urs Ganse, Yann Pfau-Kempf, Markku Alho, Maxime Dubart, Maxime Grandin, Andreas Johlander, Konstantinos Papadakis, and Minna Palmroth
Ann. Geophys., 39, 911–928, https://doi.org/10.5194/angeo-39-911-2021, https://doi.org/10.5194/angeo-39-911-2021, 2021
Short summary
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We use simulations of Earth's magnetosphere and study the formation of transient wave structures in the region where the solar wind first interacts with the magnetosphere. These transients move earthward and play a part in the solar wind–magnetosphere interaction. We show that the transients are a common feature and their properties are altered as they move earthward, including an increase in temperature, decrease in solar wind speed and an alteration in their propagation properties.
Markus Battarbee, Thiago Brito, Markku Alho, Yann Pfau-Kempf, Maxime Grandin, Urs Ganse, Konstantinos Papadakis, Andreas Johlander, Lucile Turc, Maxime Dubart, and Minna Palmroth
Ann. Geophys., 39, 85–103, https://doi.org/10.5194/angeo-39-85-2021, https://doi.org/10.5194/angeo-39-85-2021, 2021
Short summary
Short summary
We investigate local acceleration dynamics of electrons with a new numerical simulation method, which is an extension of a world-leading kinetic plasma simulation. We describe how large supercomputer simulations can be used to initialize the electron simulations and show numerical stability for the electron method. We show that features of our simulated electrons match observations from Earth's magnetic tail region.
Markus Battarbee, Xóchitl Blanco-Cano, Lucile Turc, Primož Kajdič, Andreas Johlander, Vertti Tarvus, Stephen Fuselier, Karlheinz Trattner, Markku Alho, Thiago Brito, Urs Ganse, Yann Pfau-Kempf, Mojtaba Akhavan-Tafti, Tomas Karlsson, Savvas Raptis, Maxime Dubart, Maxime Grandin, Jonas Suni, and Minna Palmroth
Ann. Geophys., 38, 1081–1099, https://doi.org/10.5194/angeo-38-1081-2020, https://doi.org/10.5194/angeo-38-1081-2020, 2020
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We investigate the dynamics of helium in the foreshock, a part of near-Earth space found upstream of the Earth's bow shock. We show how the second most common ion in interplanetary space reacts strongly to plasma waves found in the foreshock. Spacecraft observations and supercomputer simulations both give us a new understanding of the foreshock edge and how to interpret future observations.
Yann Pfau-Kempf, Konstantinos Papadakis, Markku Alho, Markus Battarbee, Giulia Cozzani, Lauri Pänkäläinen, Urs Ganse, Fasil Kebede, Jonas Suni, Konstantinos Horaites, Maxime Grandin, and Minna Palmroth
Ann. Geophys., 43, 469–488, https://doi.org/10.5194/angeo-43-469-2025, https://doi.org/10.5194/angeo-43-469-2025, 2025
Short summary
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Flux ropes are peculiar structures of twisted magnetic field occurring in many regions of space, near Earth and other planets, at the Sun, and in astrophysical objects. We developed a new way of detecting flux ropes in large supercomputer simulations of near-Earth space, and we use it to follow the evolution of flux ropes for long distances past the Earth in the flow direction. This will be useful in future studies as these flux ropes are involved in the transport of matter and energy in space.
Abiyot Bires Workayehu, Minna Palmroth, Maxime Grandin, Liisa Juusola, Markku Alho, Ivan Zaitsev, Venla Koikkalainen, Konstantinos Horaites, Yann Pfau-Kempf, Urs Ganse, Markus Battarbee, and Jonas Suni
EGUsphere, https://doi.org/10.5194/egusphere-2025-2282, https://doi.org/10.5194/egusphere-2025-2282, 2025
Short summary
Short summary
We investigate the ionospheric signatures of BBFs in the magnetotail utilising a global 6D hybrid-Vlasov simulation coupled with an ionospheric model. We analyse changes in the magnitudes of ionospheric observables and use them as the ionospheric manifestations of bursty bulk flows. Our results reveal that reconnection-driven BBF induce vortices that generate FACs, which map to the ionosphere with distinct east-west alignment and exhibit a characteristic westward drift.
Venla Koikkalainen, Maxime Grandin, Emilia Kilpua, Abiyot Workayehu, Ivan Zaitsev, Liisa Juusola, Shi Tao, Markku Alho, Lauri Pänkäläinen, Giulia Cozzani, Konstantinos Horaites, Jonas Suni, Yann Pfau-Kempf, Urs Ganse, and Minna Palmroth
EGUsphere, https://doi.org/10.5194/egusphere-2025-2265, https://doi.org/10.5194/egusphere-2025-2265, 2025
Short summary
Short summary
We use a numerical simulation to study phenomena that occur between the Earth’s dipolar magnetic field and the nightside of near-Earth space. We observe the formation of large-scale vortex flows with scales of several Earth radii. On the ionospheric grid of the simulation we find that the field-aligned currents formed in the simulation reflect the vortex flow in the transition region. The main finding is that the vortex flow is a result of a combination of flow dynamics and a plasma instability.
Liisa Juusola, Ilkka Virtanen, Spencer Mark Hatch, Heikki Vanhamäki, Maxime Grandin, Noora Partamies, Urs Ganse, Ilja Honkonen, Abiyot Workayehu, Antti Kero, and Minna Palmroth
EGUsphere, https://doi.org/10.5194/egusphere-2025-2394, https://doi.org/10.5194/egusphere-2025-2394, 2025
Short summary
Short summary
Key properties of the ionospheric electrodynamics are electric fields, currents, and conductances. They provide a window to the vast and distant near-Earth space, cause Joule heating that affect satellite orbits, and drive geomagnetically induced currents (GICs) in technological conductor networks. We have developed a new method for solving the key properties of ionospheric electrodynamics from ground-based magnetic field observations.
Shi Tao, Markku Alho, Ivan Zaitsev, Lucile Turc, Markus Battarbee, Urs Ganse, Yann Pfau-Kempf, and Minna Palmroth
EGUsphere, https://doi.org/10.5194/egusphere-2025-1340, https://doi.org/10.5194/egusphere-2025-1340, 2025
Short summary
Short summary
Plasma convection is the movement of plasma that drags the magnetic field lines with it. Magnetic field in the solar wind interacts with the Earth's magnetic field and drags the dayside field lines of the Earth's magnetosphere toward nightside, causing the plasma inside the magnetosphere to circulate around the Earth in a process called the Dungey Cycle. Our simulation and methodology desribe this cycle in detail and find features in the convection that are not explained by fluid models.
Tuomas Häkkilä, Maxime Grandin, Markus Battarbee, Monika E. Szeląg, Markku Alho, Leo Kotipalo, Niilo Kalakoski, Pekka T. Verronen, and Minna Palmroth
Ann. Geophys., 43, 217–240, https://doi.org/10.5194/angeo-43-217-2025, https://doi.org/10.5194/angeo-43-217-2025, 2025
Short summary
Short summary
We study the atmospheric impact of auroral electron precipitation through the novel combination of both magnetospheric modelling and atmospheric modelling. We first simulate fluxes of auroral electrons and then use these fluxes to model their atmospheric impact. We find an increase of more than 200 % in thermospheric odd nitrogen and a corresponding decrease in stratospheric ozone of around 0.8 %. The produced auroral electron precipitation is realistic and shows potential for future studies.
Anton Fetzer, Mikko Savola, Adnane Osmane, Vili-Arttu Ketola, Philipp Oleynik, and Minna Palmroth
EGUsphere, https://doi.org/10.5194/egusphere-2025-1279, https://doi.org/10.5194/egusphere-2025-1279, 2025
Short summary
Short summary
Extreme events can pose serious risks to satellites, potentially disrupting communication, navigation, and power systems. Our study estimates the worst-case radiation levels during such an event and assesses their impact on electronics and solar panels.
Urs Ganse, Yann Pfau-Kempf, Hongyang Zhou, Liisa Juusola, Abiyot Workayehu, Fasil Kebede, Konstantinos Papadakis, Maxime Grandin, Markku Alho, Markus Battarbee, Maxime Dubart, Leo Kotipalo, Arnaud Lalagüe, Jonas Suni, Konstantinos Horaites, and Minna Palmroth
Geosci. Model Dev., 18, 511–527, https://doi.org/10.5194/gmd-18-511-2025, https://doi.org/10.5194/gmd-18-511-2025, 2025
Short summary
Short summary
Vlasiator is a kinetic space plasma model that simulates the behavior of plasma, solar wind and magnetic fields in near-Earth space. So far, these simulations have been run without any interaction with the ionosphere, the uppermost layer of Earth's atmosphere. In this paper, we present the new methods that add an ionospheric electrodynamics model to Vlasiator, coupling it with the existing methods and presenting new simulation results of how space plasma and Earth's ionosphere interact.
Leo Kotipalo, Markus Battarbee, Yann Pfau-Kempf, and Minna Palmroth
Geosci. Model Dev., 17, 6401–6413, https://doi.org/10.5194/gmd-17-6401-2024, https://doi.org/10.5194/gmd-17-6401-2024, 2024
Short summary
Short summary
This paper examines a method called adaptive mesh refinement in optimization of the space plasma simulation model Vlasiator. The method locally adjusts resolution in regions which are most relevant to modelling, based on the properties of the plasma. The runs testing this method show that adaptive refinement manages to highlight the desired regions with manageable performance overhead. Performance in larger-scale production runs and mitigation of overhead are avenues of further research.
Sanni Hoilijoki, Emilia Kilpua, Adnane Osmane, Lucile Turc, Mikko Savola, Veera Lipsanen, Harriet George, and Milla Kalliokoski
Ann. Geophys. Discuss., https://doi.org/10.5194/angeo-2024-3, https://doi.org/10.5194/angeo-2024-3, 2024
Revised manuscript under review for ANGEO
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Structures originating from the Sun, such as coronal mass ejections and high-speed streams, may impact the Earth's magnetosphere differently. The occurrence rate of these structures depends on the phase solar cycle. We use mutual information to study the change in the statistical dependence between solar wind and inner magnetosphere. We find that the non-linearity between solar wind and inner magnetosphere varies over the solar cycle and during different solar wind drivers.
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
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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.
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.
Fasil Tesema, Noora Partamies, Daniel K. Whiter, and Yasunobu Ogawa
Ann. Geophys., 40, 1–10, https://doi.org/10.5194/angeo-40-1-2022, https://doi.org/10.5194/angeo-40-1-2022, 2022
Short summary
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.
Vertti Tarvus, Lucile Turc, Markus Battarbee, Jonas Suni, Xóchitl Blanco-Cano, Urs Ganse, Yann Pfau-Kempf, Markku Alho, Maxime Dubart, Maxime Grandin, Andreas Johlander, Konstantinos Papadakis, and Minna Palmroth
Ann. Geophys., 39, 911–928, https://doi.org/10.5194/angeo-39-911-2021, https://doi.org/10.5194/angeo-39-911-2021, 2021
Short summary
Short summary
We use simulations of Earth's magnetosphere and study the formation of transient wave structures in the region where the solar wind first interacts with the magnetosphere. These transients move earthward and play a part in the solar wind–magnetosphere interaction. We show that the transients are a common feature and their properties are altered as they move earthward, including an increase in temperature, decrease in solar wind speed and an alteration in their propagation properties.
Andrei Runov, Maxime Grandin, Minna Palmroth, Markus Battarbee, Urs Ganse, Heli Hietala, Sanni Hoilijoki, Emilia Kilpua, Yann Pfau-Kempf, Sergio Toledo-Redondo, Lucile Turc, and Drew Turner
Ann. Geophys., 39, 599–612, https://doi.org/10.5194/angeo-39-599-2021, https://doi.org/10.5194/angeo-39-599-2021, 2021
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In collisionless systems like space plasma, particle velocity distributions contain fingerprints of ongoing physical processes. However, it is challenging to decode this information from observations. We used hybrid-Vlasov simulations to obtain ion velocity distribution functions at different locations and at different stages of the Earth's magnetosphere dynamics. The obtained distributions provide valuable examples that may be directly compared with observations by satellites in space.
Minna Palmroth, Savvas Raptis, Jonas Suni, Tomas Karlsson, Lucile Turc, Andreas Johlander, Urs Ganse, Yann Pfau-Kempf, Xochitl Blanco-Cano, Mojtaba Akhavan-Tafti, Markus Battarbee, Maxime Dubart, Maxime Grandin, Vertti Tarvus, and Adnane Osmane
Ann. Geophys., 39, 289–308, https://doi.org/10.5194/angeo-39-289-2021, https://doi.org/10.5194/angeo-39-289-2021, 2021
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Magnetosheath jets are high-velocity features within the Earth's turbulent magnetosheath, separating the Earth's magnetic domain from the solar wind. The characteristics of the jets are difficult to assess statistically as a function of their lifetime because normally spacecraft observe them only at one position within the magnetosheath. This study first confirms the accuracy of the model used, Vlasiator, by comparing it to MMS spacecraft, and then carries out the first jet lifetime statistics.
Minna Palmroth, Maxime Grandin, Theodoros Sarris, Eelco Doornbos, Stelios Tourgaidis, Anita Aikio, Stephan Buchert, Mark A. Clilverd, Iannis Dandouras, Roderick Heelis, Alex Hoffmann, Nickolay Ivchenko, Guram Kervalishvili, David J. Knudsen, Anna Kotova, Han-Li Liu, David M. Malaspina, Günther March, Aurélie Marchaudon, Octav Marghitu, Tomoko Matsuo, Wojciech J. Miloch, Therese Moretto-Jørgensen, Dimitris Mpaloukidis, Nils Olsen, Konstantinos Papadakis, Robert Pfaff, Panagiotis Pirnaris, Christian Siemes, Claudia Stolle, Jonas Suni, Jose van den IJssel, Pekka T. Verronen, Pieter Visser, and Masatoshi Yamauchi
Ann. Geophys., 39, 189–237, https://doi.org/10.5194/angeo-39-189-2021, https://doi.org/10.5194/angeo-39-189-2021, 2021
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This is a review paper that summarises the current understanding of the lower thermosphere–ionosphere (LTI) in terms of measurements and modelling. The LTI is the transition region between space and the atmosphere and as such of tremendous importance to both the domains of space and atmosphere. The paper also serves as the background for European Space Agency Earth Explorer 10 candidate mission Daedalus.
Markus Battarbee, Thiago Brito, Markku Alho, Yann Pfau-Kempf, Maxime Grandin, Urs Ganse, Konstantinos Papadakis, Andreas Johlander, Lucile Turc, Maxime Dubart, and Minna Palmroth
Ann. Geophys., 39, 85–103, https://doi.org/10.5194/angeo-39-85-2021, https://doi.org/10.5194/angeo-39-85-2021, 2021
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We investigate local acceleration dynamics of electrons with a new numerical simulation method, which is an extension of a world-leading kinetic plasma simulation. We describe how large supercomputer simulations can be used to initialize the electron simulations and show numerical stability for the electron method. We show that features of our simulated electrons match observations from Earth's magnetic tail region.
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
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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.
Maxime Dubart, Urs Ganse, Adnane Osmane, Andreas Johlander, Markus Battarbee, Maxime Grandin, Yann Pfau-Kempf, Lucile Turc, and Minna Palmroth
Ann. Geophys., 38, 1283–1298, https://doi.org/10.5194/angeo-38-1283-2020, https://doi.org/10.5194/angeo-38-1283-2020, 2020
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Plasma waves are ubiquitous in the Earth's magnetosphere. They are responsible for many energetic processes happening in Earth's atmosphere, such as auroras. In order to understand these processes, thorough investigations of these waves are needed. We use a state-of-the-art numerical model to do so. Here we investigate the impact of different spatial resolutions in the model on these waves in order to improve in the future the model without wasting computational resources.
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
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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.
Markus Battarbee, Xóchitl Blanco-Cano, Lucile Turc, Primož Kajdič, Andreas Johlander, Vertti Tarvus, Stephen Fuselier, Karlheinz Trattner, Markku Alho, Thiago Brito, Urs Ganse, Yann Pfau-Kempf, Mojtaba Akhavan-Tafti, Tomas Karlsson, Savvas Raptis, Maxime Dubart, Maxime Grandin, Jonas Suni, and Minna Palmroth
Ann. Geophys., 38, 1081–1099, https://doi.org/10.5194/angeo-38-1081-2020, https://doi.org/10.5194/angeo-38-1081-2020, 2020
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We investigate the dynamics of helium in the foreshock, a part of near-Earth space found upstream of the Earth's bow shock. We show how the second most common ion in interplanetary space reacts strongly to plasma waves found in the foreshock. Spacecraft observations and supercomputer simulations both give us a new understanding of the foreshock edge and how to interpret future observations.
Lucile Turc, Vertti Tarvus, Andrew P. Dimmock, Markus Battarbee, Urs Ganse, Andreas Johlander, Maxime Grandin, Yann Pfau-Kempf, Maxime Dubart, and Minna Palmroth
Ann. Geophys., 38, 1045–1062, https://doi.org/10.5194/angeo-38-1045-2020, https://doi.org/10.5194/angeo-38-1045-2020, 2020
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Short summary
Using global computer simulations, we study properties of the magnetosheath, the region of near-Earth space where the stream of particles originating from the Sun, the solar wind, is slowed down and deflected around the Earth's magnetic field. One of our main findings is that even for idealised solar wind conditions as used in our model, the magnetosheath density shows large-scale spatial and temporal variation in the so-called quasi-parallel magnetosheath, causing varying levels of asymmetry.
Harriet George, Emilia Kilpua, Adnane Osmane, Timo Asikainen, Milla M. H. Kalliokoski, Craig J. Rodger, Stepan Dubyagin, and Minna Palmroth
Ann. Geophys., 38, 931–951, https://doi.org/10.5194/angeo-38-931-2020, https://doi.org/10.5194/angeo-38-931-2020, 2020
Short summary
Short summary
We compared trapped outer radiation belt electron fluxes to high-latitude precipitating electron fluxes during two interplanetary coronal mass ejections (ICMEs) with opposite magnetic cloud rotation. The electron response had many similarities and differences between the two events, indicating that different acceleration mechanisms acted. Van Allen Probe data were used for trapped electron flux measurements, and Polar Operational Environmental Satellites were used for precipitating flux data.
Cited articles
Battarbee, M., Hannuksela, O. A., Pfau-Kempf, Y., Alfthan, S. V., Ganse, U., Jarvinen, R., Leo, Suni, J., Alho, M., Turc., L., Honkonen, I., Brito, T., and Grandin, M.: Fmihpc/Analysator: V0.9, Zenodo [code], https://doi.org/10.5281/zenodo.4462514, 2021. a
Bouri, I., Franssila, F., Alho, M., Cozzani, G., Zaitsev, I., Palmroth, M., and Roos, T.: Graph Representation of the Magnetic Field Topology in High-Fidelity Plasma Simulations for Machine Learning Applications, ICML 2023 Workshop on Machine Learning for Astrophysics, Honolulu, Hawaii, USA, https://doi.org/10.48550/arXiv.2307.09469, 2023. a
Bujack, R., Tsai, K., Morley, S. K., and Bresciani, E.: Open Source Vector Field Topology, SoftwareX, 15, 100787, https://doi.org/10.1016/j.softx.2021.100787, 2021. a
Bussov, M. and Nättilä, J.: Segmentation of Turbulent Computational Fluid Dynamics Simulations with Unsupervised Ensemble Learning, Signal Processing: Image Communication, 99, 116450, https://doi.org/10.1016/j.image.2021.116450, 2021. a
Childs, H., Brugger, E., Whitlock, B., Meredith, J., Ahern, S., Pugmire, D., Biagas, K., Miller, M., Harrison, C., Weber, G. H., Krishnan, H., Fogal, T., Sanderson, A., Garth, C., Bethel, E. W., Camp, D., Rübel, O., Durant, M., Favre, J. M., and Navrátil, P.: VisIt: An End-User Tool For Visualizing and Analyzing Very Large Data, in: High Performance Visualization–Enabling Extreme-Scale Scientific Insight, Chapman and Hall/CRC, New York, https://doi.org/10.1201/b12985, pp. 357–372, 2012. a, b
Crameri, F.: Scientific Colour Maps, Zenodo, https://doi.org/10.5281/ZENODO.1243862, 2021. a
Denton, R. E., Sonnerup, B. U. Ö., Birn, J., Teh, W.-L., Drake, J. F., Swisdak, M., Hesse, M., and Baumjohann, W.: Test of Methods to Infer the Magnetic Reconnection Geometry from Spacecraft Data, J. Geophys. Res.-Space, 115, A10242, https://doi.org/10.1029/2010JA015420, 2010. a, b
Dorelli, J. C. and Bhattacharjee, A.: On the Generation and Topology of Flux Transfer Events, J. Geophys. Res.-Space, 114, A06213, https://doi.org/10.1029/2008JA013410, 2009. a
Eggington, J. W. B., Desai, R. T., Mejnertsen, L., Chittenden, J. P., and Eastwood, J. P.: Time-Varying Magnetopause Reconnection During Sudden Commencement: Global MHD Simulations, J. Geophys. Res.-Space, 127, e2021JA030006, https://doi.org/10.1029/2021JA030006, 2022. a
Fu, H. S., Vaivads, A., Khotyaintsev, Y. V., Olshevsky, V., André, M., Cao, J. B., Huang, S. Y., Retinò, A., and Lapenta, G.: How to Find Magnetic Nulls and Reconstruct Field Topology with MMS Data?, J. Geophys. Res.-Space, 120, 3758–3782, https://doi.org/10.1002/2015JA021082, 2015. a
Ganse, U., Koskela, T., Battarbee, M., Pfau-Kempf, Y., Papadakis, K., Alho, M., Bussov, M., Cozzani, G., Dubart, M., George, H., Gordeev, E., Grandin, M., Horaites, K., Suni, J., Tarvus, V., Kebede, F. T., Turc, L., Zhou, H., and Palmroth, M.: Enabling Technology for Global 3D + 3V Hybrid-Vlasov Simulations of near-Earth Space, Phys. Plasmas, 30, 042902, https://doi.org/10.1063/5.0134387, 2023. a
Genestreti, K. J., Nakamura, T. K. M., Nakamura, R., Denton, R. E., Torbert, R. B., Burch, J. L., Plaschke, F., Fuselier, S. A., Ergun, R. E., Giles, B. L., and Russell, C. T.: How Accurately Can We Measure the Reconnection Rate EM for the MMS Diffusion Region Event of 11 July 2017?, J. Geophys. Res.-Space, 123, 9130–9149, https://doi.org/10.1029/2018JA025711, 2018. a, b
Glocer, A., Dorelli, J., Toth, G., Komar, C. M., and Cassak, P. A.: Separator Reconnection at the Magnetopause for Predominantly Northward and Southward IMF: Techniques and Results, J. Geophys. Res.-Space, 121, 140–156, https://doi.org/10.1002/2015JA021417, 2016. a
Gosling, J. T. and Phan, T. D.: MAGNETIC RECONNECTION IN THE SOLAR WIND AT CURRENT SHEETS ASSOCIATED WITH EXTREMELY SMALL FIELD SHEAR ANGLES, Astrophys. J., 763, L39, https://doi.org/10.1088/2041-8205/763/2/L39, 2013. a
Grandin, M., Luttikhuis, T., Battarbee, M., Cozzani, G., Zhou, H., Turc, L., Pfau-Kempf, Y., George, H., Horaites, K., Gordeev, E., Ganse, U., Papadakis, K., Alho, M., Tesema, F., Suni, J., Dubart, M., Tarvus, V., and Palmroth, M.: First 3D Hybrid-Vlasov Global Simulation of Auroral Proton Precipitation and Comparison with Satellite Observations, J. Space Weather Spac., 13, 20, https://doi.org/10.1051/swsc/2023017, 2023. a
Greene, J. M.: Geometrical Properties of Three-Dimensional Reconnecting Magnetic Fields with Nulls, J. Geophys. Res., 93, 8583, https://doi.org/10.1029/JA093iA08p08583, 1988. a
Harris, E. G.: On a Plasma Sheath Separating Regions of Oppositely Directed Magnetic Field, Nuovo Cimento (1955–1965), 23, 115–121, https://doi.org/10.1007/BF02733547, 1962. a
Haynes, A. L. and Parnell, C. E.: A Trilinear Method for Finding Null Points in a Three-Dimensional Vector Space, Phys. Plasmas, 14, 082107, https://doi.org/10.1063/1.2756751, 2007. a
Haynes, A. L. and Parnell, C. E.: A Method for Finding Three-Dimensional Magnetic Skeletons, Phys. Plasmas, 17, 092903, https://doi.org/10.1063/1.3467499, 2010. a, b, c
Hietala, H., Phan, T. D., Angelopoulos, V., Oieroset, M., Archer, M. O., Karlsson, T., and Plaschke, F.: In Situ Observations of a Magnetosheath High-Speed Jet Triggering Magnetopause Reconnection, Geophys. Res. Lett., 45, 1732–1740, https://doi.org/10.1002/2017GL076525, 2018. a
Hoilijoki, S., Ganse, U., Pfau-Kempf, Y., Cassak, P. A., Walsh, B. M., Hietala, H., von Alfthan, S., and Palmroth, M.: Reconnection Rates and X Line Motion at the Magnetopause: Global 2D-3V Hybrid-Vlasov Simulation Results, J. Geophys. Res.-Space, 122, 2877–2888, https://doi.org/10.1002/2016ja023709, 2017. a, b
Hoilijoki, S., Ganse, U., Sibeck, D. G., Cassak, P. A., Turc, L., Battarbee, M., Fear, R. C., Blanco-Cano, X., Dimmock, A. P., Kilpua, E. K. J., Jarvinen, R., Juusola, L., Pfau-Kempf, Y., and Palmroth, M.: Properties of Magnetic Reconnection and FTEs on the Dayside Magnetopause With and Without Positive IMF Bx Component During Southward IMF, J. Geophys. Res.-Space, 124, 4037–4048, https://doi.org/10.1029/2019JA026821, 2019. a
Horaites, K., Rintamäki, E., Zaitsev, I., Turc, L., Grandin, M., Cozzani, G., Zhou, H., Alho, M., Suni, J., Kebede, F., Gordeev, E., George, H., Battarbee, M., Bussov, M., Dubart, M., Ganse, U., Papadakis, K., Pfau-Kempf, Y., Tarvus, V., and Palmroth, M.: Magnetospheric Response to a Pressure Pulse in a Three-Dimensional Hybrid-Vlasov Simulation, J. Geophys. Res.-Space, 128, e2023JA031374, https://doi.org/10.1029/2023JA031374, 2023. a, b
Hu, Y. Q., Peng, Z., Wang, C., and Kan, J. R.: Magnetic Merging Line and Reconnection Voltage versus IMF Clock Angle: Results from Global MHD Simulations, J. Geophys. Res.-Space, 114, A08220, https://doi.org/10.1029/2009JA014118, 2009. a, b
Keinert, B., Schäfer, H., Korndörfer, J., Ganse, U., and Stamminger, M.: Improved Ray Casting of Procedural Distance Bounds, Journal of Graphics Tools, 17, 127–138, https://doi.org/10.1080/2165347X.2015.1033069, 2013. a
Korndörfer, J. and Keinert, B., Ganse, U., Sänger, M., Ley, S., Burkhardt, K., Spuler, M., and Heusipp, J.: HG_SDF: A glsl library for building signed distance functions, Mercury Demogroup, https://mercury.sexy/hg_sdf (last access: 25 April 2023), 2015. a
Laitinen, T. V., Janhunen, P., Pulkkinen, T. I., Palmroth, M., and Koskinen, H. E. J.: On the characterization of magnetic reconnection in global MHD simulations, Ann. Geophys., 24, 3059–3069, https://doi.org/10.5194/angeo-24-3059-2006, 2006. a, b, c
Lapenta, G.: Detecting Reconnection Sites Using the Lorentz Transformations for Electromagnetic Fields, Astrophys. J., 911, 147, https://doi.org/10.3847/1538-4357/abeb74, 2021. a
Lau, Y.-T. and Finn, J. M.: Three-Dimensional Kinematic Reconnection in the Presence of Field Nulls and Closed Field Lines, Astrophys. J., 350, 672, https://doi.org/10.1086/168419, 1990. a
Olshevsky, V., Divin, A., Eriksson, E., Markidis, S., and Lapenta, G.: ENERGY DISSIPATION IN MAGNETIC NULL POINTS AT KINETIC SCALES, Astrophys. J., 807, 155, https://doi.org/10.1088/0004-637X/807/2/155, 2015. a
Olshevsky, V., Deca, J., Divin, A., Peng, I. B., Markidis, S., Innocenti, M. E., Cazzola, E., and Lapenta, G.: MAGNETIC NULL POINTS IN KINETIC SIMULATIONS OF SPACE PLASMAS, Astrophys. J., 819, 52, https://doi.org/10.3847/0004-637X/819/1/52, 2016. a, b
Palmroth, M.: Vlasiator 6D 'EGI' Tail Current Sheet Data Series, University of Helsinki [data set], https://doi.org/10.23729/72EFF3EF-C84B-43B8-94D1-0A8B49C7C56D, 2023. a, b
Palmroth, M., Hoilijoki, S., Juusola, L., Pulkkinen, T. I., Hietala, H., Pfau-Kempf, Y., Ganse, U., von Alfthan, S., Vainio, R., and Hesse, M.: Tail reconnection in the global magnetospheric context: Vlasiator first results, Ann. Geophys., 35, 1269–1274, https://doi.org/10.5194/angeo-35-1269-2017, 2017. a, b
Palmroth, M., Ganse, U., Pfau-Kempf, Y., Battarbee, M., Turc, L., Brito, T., Grandin, M., Hoilijoki, S., Sandroos, A., and von Alfthan, S.: Vlasov Methods in Space Physics and Astrophysics, Living Reviews in Computational Astrophysics, 4, 1, https://doi.org/10.1007/s41115-018-0003-2, 2018. a
Palmroth, M., Pulkkinen, T. I., Ganse, U., Pfau-Kempf, Y., Koskela, T., Zaitsev, I., Alho, M., Cozzani, G., Turc, L., Battarbee, M., Dubart, M., George, H., Gordeev, E., Grandin, M., Horaites, K., Osmane, A., Papadakis, K., Suni, J., Tarvus, V., Zhou, H., and Nakamura, R.: Magnetotail Plasma Eruptions Driven by Magnetic Reconnection and Kinetic Instabilities, Nat. Geosci., 16, 570–576, https://doi.org/10.1038/s41561-023-01206-2, 2023. a, b, c, d, e, f, g, h, i, j
Parker, E. N.: Sweet's Mechanism for Merging Magnetic Fields in Conducting Fluids, J. Geophys. Res. (1896–1977), 62, 509–520, https://doi.org/10.1029/JZ062i004p00509, 1957. a
Parnell, C. E., Smith, J. M., Neukirch, T., and Priest, E. R.: The Structure of Three-dimensional Magnetic Neutral Points, Phys. Plasmas, 3, 759–770, https://doi.org/10.1063/1.871810, 1996. a
Parnell, C. E., Haynes, A. L., and Galsgaard, K.: Structure of Magnetic Separators and Separator Reconnection, J. Geophys. Res.-Space, 115, A02102, https://doi.org/10.1029/2009JA014557, 2010. a
Paschmann, G. and Daly, P. W.: Analysis Methods for Multi-Spacecraft Data, no. SR-001 in ISSI Scientific Report, ESA Publications Division, ESA Publications Division Keplerlaan 1, 2200 AG Noordwijk, the Netherlands, 1998. a
Pathak, N., Ergun, R. E., Qi, Y., Schwartz, S. J., Vo, T., Usanova, M. E., Hesse, M., Phan, T. D., Drake, J. F., Eriksson, S., Ahmadi, N., Chasapis, A., Wilder, F. D., Stawarz, J. E., Burch, J. L., Genestreti, K. J., Torbert, R. B., and Nakamura, R.: Evidence of a Nonorthogonal X-line in Guide-field Magnetic Reconnection, Astrophys. J. Letters, 941, L34, https://doi.org/10.3847/2041-8213/aca679, 2022. a
Pfau-Kempf, Y., Palmroth, M., Johlander, A., Turc, L., Alho, M., Battarbee, M., Dubart, M., Grandin, M., and Ganse, U.: Hybrid-Vlasov Modeling of Three-Dimensional Dayside Magnetopause Reconnection, Phys. Plasmas, 27, 092903, https://doi.org/10.1063/5.0020685, 2020. a, b
Pfau-Kempf, Y., von Alfthan, S., Ganse, U., Sandroos, A., Battarbee, M., Koskela, T., Otto, Ilja, Papadakis, K., Kotipalo, L., Zhou, H., Grandin, M., Pokhotelov, D., and Alho, M.: Fmihpc/Vlasiator: Vlasiator, Zenodo [code], https://doi.org/10.5281/zenodo.3640593, 2022. a
Priest, E. R. and Titov, V. S.: Magnetic Reconnection at Three-Dimensional Null Points, Philos. T. Roy. Soc. A, 354, 2951–2992, https://doi.org/10.1098/rsta.1996.0136, 1996. a
Rezeau, L., Belmont, G., Manuzzo, R., Aunai, N., and Dargent, J.: Analyzing the Magnetopause Internal Structure: New Possibilities Offered by MMS Tested in a Case Study, J. Geophys. Res.-Space, 123, 227–241, https://doi.org/10.1002/2017JA024526, 2018. a, b
Servidio, S., Matthaeus, W. H., Shay, M. A., Cassak, P. A., and Dmitruk, P.: Magnetic Reconnection in Two-Dimensional Magnetohydrodynamic Turbulence, Phys. Rev. Lett., 102, 115003, https://doi.org/10.1103/PhysRevLett.102.115003, 2009. a
Shen, C., Rong, Z. J., Li, X., Dunlop, M., Liu, Z. X., Malova, H. V., Lucek, E., and Carr, C.: Magnetic configurations of the tilted current sheets in magnetotail, Ann. Geophys., 26, 3525–3543, https://doi.org/10.5194/angeo-26-3525-2008, 2008. a
Shi, Q. Q., Tian, A. M., Bai, S. C., Hasegawa, H., Degeling, A. W., Pu, Z. Y., Dunlop, M., Guo, R. L., Yao, S. T., Zong, Q.-G., Wei, Y., Zhou, X.-Z., Fu, S. Y., and Liu, Z. Q.: Dimensionality, Coordinate System and Reference Frame for Analysis of In-Situ Space Plasma and Field Data, Space Sci. Rev., 215, 35, https://doi.org/10.1007/s11214-019-0601-2, 2019. a, b, c, d, e, f
Sonnerup, B. and Scheible, M.: Minimum and Maximum Variance Analysis, in: Analysis Methods for Multi-Spacecraft Data, vol. 001 of ISSI Scientific Report, International Space Science Institute, Bern, Switzerland, pp. 185–220, 1998. a
Sonnerup, B. U. Ö.: Magnetic-Field Re-Connexion in a Highly Conducting Incompressible Fluid, J. Plasma Phys., 4, 161–174, https://doi.org/10.1017/S0022377800004888, 1970. a
Sonnerup, B. U. Ö.: Magnetopause Reconnection Rate, J. Geophys. Res. (1896–1977), 79, 1546–1549, https://doi.org/10.1029/JA079i010p01546, 1974. a
Titov, V. S., Forbes, T. G., Priest, E. R., Mikić, Z., and Linker, J. A.: SLIP-SQUASHING FACTORS AS A MEASURE OF THREE-DIMENSIONAL MAGNETIC RECONNECTION, Astrophys. J., 693, 1029, https://doi.org/10.1088/0004-637X/693/1/1029, 2009. a
von Alfthan, S., Pokhotelov, D., Kempf, Y., Hoilijoki, S., Honkonen, I., Sandroos, A., and Palmroth, M.: Vlasiator: First Global Hybrid-Vlasov Simulations of Earth's Foreshock and Magnetosheath, J. Atmos. Sol.-Terr. Phy, 120, 24–35, https://doi.org/10.1016/j.jastp.2014.08.012, 2014. a
Xu, S., Liemohn, M. W., Dong, C., Mitchell, D. L., Bougher, S. W., and Ma, Y.: Pressure and Ion Composition Boundaries at Mars, J. Geophys. Res.-Space, 121, 6417–6429, https://doi.org/10.1002/2016JA022644, 2016. a
Yeates, A. R. and Hornig, G.: A Generalized Flux Function for Three-Dimensional Magnetic Reconnection, Phys. Plasmas, 18, 102118, https://doi.org/10.1063/1.3657424, 2011. a
Yeh, T.: Reconnection of Magnetic Field Lines in Viscous Conducting Fluids, J. Geophys. Res. (1896-1977), 81, 4524–4530, https://doi.org/10.1029/JA081i025p04524, 1976. a
Zeiler, A., Biskamp, D., Drake, J. F., Rogers, B. N., Shay, M. A., and Scholer, M.: Three-Dimensional Particle Simulations of Collisionless Magnetic Reconnection, J. Geophys. Res.-Space, 107, SMP 6-1–SMP 6-9, https://doi.org/10.1029/2001JA000287, 2002. a
Short summary
Magnetic reconnection is one of the main processes for energy conversion and plasma transport in space plasma physics, associated with plasma entry into the magnetosphere of Earth and Earth’s substorm cycle. Global modelling of these plasma processes enables us to understand the magnetospheric system in detail. However, finding sites of active reconnection from large simulation datasets can be challenging, and this paper develops tools to find magnetic topologies related to reconnection.
Magnetic reconnection is one of the main processes for energy conversion and plasma transport in...
