Articles | Volume 39, issue 2
https://doi.org/10.5194/angeo-39-289-2021
© Author(s) 2021. 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-39-289-2021
© Author(s) 2021. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Regular paper
| 
12 Mar 2021
Regular paper |
| 12 Mar 2021
| 12 Mar 2021
Magnetosheath jet evolution as a function of lifetime: global hybrid-Vlasov simulations compared to MMS observations
Minna Palmroth
CORRESPONDING AUTHOR
Department of Physics, University of Helsinki, Helsinki, Finland
Space and Earth Observation Centre, Finnish Meteorological Institute, Helsinki, Finland
Savvas Raptis
KTH Royal Institute of Technology, Stockholm, Sweden
Jonas Suni
Department of Physics, University of Helsinki, Helsinki, Finland
Tomas Karlsson
KTH Royal Institute of Technology, Stockholm, Sweden
Lucile Turc
Department of Physics, University of Helsinki, Helsinki, Finland
Andreas Johlander
Department of Physics, University of Helsinki, Helsinki, Finland
Urs Ganse
Department of Physics, University of Helsinki, Helsinki, Finland
Yann Pfau-Kempf
Department of Physics, University of Helsinki, Helsinki, Finland
Xochitl Blanco-Cano
Instituto de Geofisica, Universidad Nacional Autonoma de Mexico, Mexico City, Mexico
Mojtaba Akhavan-Tafti
Climate and Space Science and Engineering, University of Michigan, Ann Arbor, USA
Markus Battarbee
Department of Physics, University of Helsinki, Helsinki, Finland
Maxime Dubart
Department of Physics, University of Helsinki, Helsinki, Finland
Maxime Grandin
Department of Physics, University of Helsinki, Helsinki, Finland
Vertti Tarvus
Department of Physics, University of Helsinki, Helsinki, Finland
Adnane Osmane
Department of Physics, University of Helsinki, Helsinki, Finland
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Leo Kotipalo, Markus Battarbee, Yann Pfau-Kempf, and Minna Palmroth
EGUsphere, https://doi.org/10.5194/egusphere-2024-301, https://doi.org/10.5194/egusphere-2024-301, 2024
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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 model, 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.
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.
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
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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
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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
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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.
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, 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.
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.
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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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
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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.
Milla M. H. Kalliokoski, Emilia K. J. Kilpua, Adnane Osmane, Drew L. Turner, Allison N. Jaynes, Lucile Turc, Harriet George, and Minna Palmroth
Ann. Geophys., 38, 683–701, https://doi.org/10.5194/angeo-38-683-2020, https://doi.org/10.5194/angeo-38-683-2020, 2020
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We present a comprehensive statistical study of the response of the Earth's space environment in sheath regions prior to interplanetary coronal mass ejections. The inner magnetospheric wave activity is enhanced in sheath regions, and the sheaths cause significant changes to the outer radiation belt electron fluxes over short timescales. We also show that non-geoeffective sheaths can result in a significant response.
Markus Battarbee, Urs Ganse, Yann Pfau-Kempf, Lucile Turc, Thiago Brito, Maxime Grandin, Tuomas Koskela, and Minna Palmroth
Ann. Geophys., 38, 625–643, https://doi.org/10.5194/angeo-38-625-2020, https://doi.org/10.5194/angeo-38-625-2020, 2020
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The structure and medium-scale dynamics of Earth's bow shock and how charged solar wind particles are reflected by it are studied in order to better understand space weather effects. We use advanced supercomputer simulations to model the shock and reflected ions. We find that the thickness of the shock depends on solar wind conditions but also has small-scale variations. Charged particle reflection is shown to be non-localized. Magnetic fields are important for ion reflection.
Theodoros E. Sarris, Elsayed R. Talaat, Minna Palmroth, Iannis Dandouras, Errico Armandillo, Guram Kervalishvili, Stephan Buchert, Stylianos Tourgaidis, David M. Malaspina, Allison N. Jaynes, Nikolaos Paschalidis, John Sample, Jasper Halekas, Eelco Doornbos, Vaios Lappas, Therese Moretto Jørgensen, Claudia Stolle, Mark Clilverd, Qian Wu, Ingmar Sandberg, Panagiotis Pirnaris, and Anita Aikio
Geosci. Instrum. Method. Data Syst., 9, 153–191, https://doi.org/10.5194/gi-9-153-2020, https://doi.org/10.5194/gi-9-153-2020, 2020
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Daedalus aims to measure the largely unexplored area between Eart's atmosphere and space, the Earth's
ignorosphere. Here, intriguing and complex processes govern the deposition and transport of energy. The aim is to quantify this energy by measuring effects caused by electrodynamic processes in this region. The concept is based on a mother satellite that carries a suite of instruments, along with smaller satellites carrying a subset of instruments that are released into the atmosphere.
Emilia Kilpua, Liisa Juusola, Maxime Grandin, Antti Kero, Stepan Dubyagin, Noora Partamies, Adnane Osmane, Harriet George, Milla Kalliokoski, Tero Raita, Timo Asikainen, and Minna Palmroth
Ann. Geophys., 38, 557–574, https://doi.org/10.5194/angeo-38-557-2020, https://doi.org/10.5194/angeo-38-557-2020, 2020
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Coronal mass ejection sheaths and ejecta are key drivers of significant space weather storms, and they cause dramatic changes in radiation belt electron fluxes. Differences in precipitation of high-energy electrons from the belts to the upper atmosphere are thus expected. We investigate here differences in sheath- and ejecta-induced precipitation using the Finnish riometer (relative ionospheric opacity meter) chain.
Maxime Grandin, Markus Battarbee, Adnane Osmane, Urs Ganse, Yann Pfau-Kempf, Lucile Turc, Thiago Brito, Tuomas Koskela, Maxime Dubart, and Minna Palmroth
Ann. Geophys., 37, 791–806, https://doi.org/10.5194/angeo-37-791-2019, https://doi.org/10.5194/angeo-37-791-2019, 2019
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When the terrestrial magnetic field is disturbed, particles from the near-Earth space can precipitate into the upper atmosphere. This work presents, for the first time, numerical simulations of proton precipitation in the energy range associated with the production of aurora (∼1–30 keV) using a global kinetic model of the near-Earth space: Vlasiator. We find that nightside proton precipitation can be regulated by the transition region between stretched and dipolar geomagnetic field lines.
Antti Lakka, Tuija I. Pulkkinen, Andrew P. Dimmock, Emilia Kilpua, Matti Ala-Lahti, Ilja Honkonen, Minna Palmroth, and Osku Raukunen
Ann. Geophys., 37, 561–579, https://doi.org/10.5194/angeo-37-561-2019, https://doi.org/10.5194/angeo-37-561-2019, 2019
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We study how the Earth's space environment responds to two different amplitude interplanetary coronal mass ejection (ICME) events that occurred in 2012 and 2014 by using the GUMICS-4 global MHD model. We examine local and large-scale dynamics of the Earth's space environment and compare simulation results to in situ data. It is shown that during moderate driving simulation agrees well with the measurements; however, GMHD results should be interpreted cautiously during strong driving.
Liisa Juusola, Sanni Hoilijoki, Yann Pfau-Kempf, Urs Ganse, Riku Jarvinen, Markus Battarbee, Emilia Kilpua, Lucile Turc, and Minna Palmroth
Ann. Geophys., 36, 1183–1199, https://doi.org/10.5194/angeo-36-1183-2018, https://doi.org/10.5194/angeo-36-1183-2018, 2018
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The solar wind interacts with the Earth’s magnetic field, forming a magnetosphere. On the night side solar wind stretches the magnetosphere into a long tail. A process called magnetic reconnection opens the magnetic field lines and reconnects them, accelerating particles to high energies. We study this in the magnetotail using a numerical simulation model of the Earth’s magnetosphere. We study the motion of the points where field lines reconnect and the fast flows driven by this process.
Minna Palmroth, Heli Hietala, Ferdinand Plaschke, Martin Archer, Tomas Karlsson, Xóchitl Blanco-Cano, David Sibeck, Primož Kajdič, Urs Ganse, Yann Pfau-Kempf, Markus Battarbee, and Lucile Turc
Ann. Geophys., 36, 1171–1182, https://doi.org/10.5194/angeo-36-1171-2018, https://doi.org/10.5194/angeo-36-1171-2018, 2018
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Magnetosheath jets are high-velocity plasma structures that are commonly observed within the Earth's magnetosheath. Previously, they have mainly been investigated with spacecraft observations, which do not allow us to infer their spatial sizes, temporal evolution, or origin. This paper shows for the first time their dimensions, evolution, and origins within a simulation whose dimensions are directly comparable to the Earth's magnetosphere. The results are compared to previous observations.
Xochitl Blanco-Cano, Markus Battarbee, Lucile Turc, Andrew P. Dimmock, Emilia K. J. Kilpua, Sanni Hoilijoki, Urs Ganse, David G. Sibeck, Paul A. Cassak, Robert C. Fear, Riku Jarvinen, Liisa Juusola, Yann Pfau-Kempf, Rami Vainio, and Minna Palmroth
Ann. Geophys., 36, 1081–1097, https://doi.org/10.5194/angeo-36-1081-2018, https://doi.org/10.5194/angeo-36-1081-2018, 2018
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We use the Vlasiator code to study the characteristics of transient structures that exist in the Earth's foreshock, i.e. upstream of the bow shock. The structures are cavitons and spontaneous hot flow anomalies (SHFAs). These transients can interact with the bow shock. We study the changes the shock suffers via this interaction. We also investigate ion distributions associated with the cavitons and SHFAs. A very important result is that the arrival of multiple SHFAs results in shock erosion.
Liisa Juusola, Yann Pfau-Kempf, Urs Ganse, Markus Battarbee, Thiago Brito, Maxime Grandin, Lucile Turc, and Minna Palmroth
Ann. Geophys., 36, 1027–1035, https://doi.org/10.5194/angeo-36-1027-2018, https://doi.org/10.5194/angeo-36-1027-2018, 2018
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The Earth's magnetic field is shaped by the solar wind. On the dayside the field is compressed and on the nightside it is stretched as a long tail. The tail has been observed to occasionally undergo flapping motions, but the origin of these motions is not understood. We study the flapping using a numerical simulation of the near-Earth space. We present a possible explanation for how the flapping could be initiated by a passing disturbance and then maintained as a standing wave.
Minna Palmroth, Sanni Hoilijoki, Liisa Juusola, Tuija I. Pulkkinen, Heli Hietala, Yann Pfau-Kempf, Urs Ganse, Sebastian von Alfthan, Rami Vainio, and Michael Hesse
Ann. Geophys., 35, 1269–1274, https://doi.org/10.5194/angeo-35-1269-2017, https://doi.org/10.5194/angeo-35-1269-2017, 2017
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Much like solar flares, substorms occurring within the Earth's magnetic domain are explosive events that cause vivid auroral displays. A decades-long debate exists to explain the substorm onset. We devise a simulation encompassing the entire near-Earth space and demonstrate that detailed modelling of magnetic reconnection explains the central substorm observations. Our results help to understand the unpredictable substorm process, which will significantly improve space weather forecasts.
Antti Lakka, Tuija I. Pulkkinen, Andrew P. Dimmock, Adnane Osmane, Ilja Honkonen, Minna Palmroth, and Pekka Janhunen
Ann. Geophys., 35, 907–922, https://doi.org/10.5194/angeo-35-907-2017, https://doi.org/10.5194/angeo-35-907-2017, 2017
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We studied the impact on global MHD simulations from different simulation initialisation methods. While the global MHD code used is GUMICS-4 we conclude that the results might be generalisable to other codes as well. It is found that different initialisation methods affect the dynamics of the Earth's space environment by creating differences in momentum transport several hours afterwards. These differences may even grow as a response to rapid solar wind condition changes.
Yann Pfau-Kempf, Heli Hietala, Steve E. Milan, Liisa Juusola, Sanni Hoilijoki, Urs Ganse, Sebastian von Alfthan, and Minna Palmroth
Ann. Geophys., 34, 943–959, https://doi.org/10.5194/angeo-34-943-2016, https://doi.org/10.5194/angeo-34-943-2016, 2016
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We have simulated the interaction of the solar wind – the charged particles and magnetic fields emitted by the Sun into space – with the magnetic field of the Earth. The solar wind flows supersonically and creates a shock when it encounters the obstacle formed by the geomagnetic field. We have identified a new chain of events which causes phenomena in the downstream region to eventually cause perturbations at the shock and even upstream. This is confirmed by ground and satellite observations.
P. T. Verronen, M. E. Andersson, A. Kero, C.-F. Enell, J. M. Wissing, E. R. Talaat, K. Kauristie, M. Palmroth, T. E. Sarris, and E. Armandillo
Ann. Geophys., 33, 381–394, https://doi.org/10.5194/angeo-33-381-2015, https://doi.org/10.5194/angeo-33-381-2015, 2015
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Electron concentrations observed by EISCAT radars can be reasonable well represented using AIMOS v1.2 satellite-data-based ionization model and SIC D-region ion chemistry model. SIC-EISCAT difference varies from event to event, probably because the statistical nature of AIMOS ionization is not capturing all the spatio-temporal fine structure of electron precipitation. Below 90km, AIMOS overestimates electron ionization because of proton contamination of the satellite electron detectors.
D. Pokhotelov, S. von Alfthan, Y. Kempf, R. Vainio, H. E. J. Koskinen, and M. Palmroth
Ann. Geophys., 31, 2207–2212, https://doi.org/10.5194/angeo-31-2207-2013, https://doi.org/10.5194/angeo-31-2207-2013, 2013
A. T. Aikio, T. Pitkänen, I. Honkonen, M. Palmroth, and O. Amm
Ann. Geophys., 31, 1021–1034, https://doi.org/10.5194/angeo-31-1021-2013, https://doi.org/10.5194/angeo-31-1021-2013, 2013
Tomas Karlsson, Ferdinand Plaschke, Austin N. Glass, and Jim M. Raines
Ann. Geophys., 42, 117–130, https://doi.org/10.5194/angeo-42-117-2024, https://doi.org/10.5194/angeo-42-117-2024, 2024
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The solar wind interacts with the planets in the solar system and creates a supersonic shock in front of them. The upstream region of this shock contains many complicated phenomena. One such phenomenon is small-scale structures of strong magnetic fields (SLAMS). These SLAMS have been observed at Earth and are important in determining the properties of space around the planet. Until now, SLAMS have not been observed at Mercury, but we show for the first time that SLAMS also exist there.
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
Preprint 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.
Maxime Grandin, Noora Partamies, and Ilkka I. Virtanen
EGUsphere, https://doi.org/10.5194/egusphere-2024-483, https://doi.org/10.5194/egusphere-2024-483, 2024
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Auroral displays typically take place at high latitudes, but the exact latitude where the auroral breakup occurs can vary. In this study, we compare the characteristics of the fluxes of precipitating electrons from space during auroral breakups occurring above Tromsø (central part of the auroral zone) and above Svalbard (poleward boundary of the auroral zone). We find that electrons responsible for the aurora above Tromsø carry more energy than those precipitating above Svalbard.
Leo Kotipalo, Markus Battarbee, Yann Pfau-Kempf, and Minna Palmroth
EGUsphere, https://doi.org/10.5194/egusphere-2024-301, https://doi.org/10.5194/egusphere-2024-301, 2024
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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 model, 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.
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.
Emilia Katja Johanna Kilpua, Simon Good, Matti Ala-Lahti, Adnane Osmane, and Venla Koikkalainen
EGUsphere, https://doi.org/10.5194/egusphere-2023-2352, https://doi.org/10.5194/egusphere-2023-2352, 2023
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The solar wind is organised to slow and fast streams, interaction regions and transient structures originating from solar eruptions. Their internal characteristics are not well understood. The more comprehensive understanding of such features can give insight on physical processes governing their formation and evolution. Using tools from information theory we find that the solar wind shows universal turbulent properties on smaller scales while on larger-scale clear differences arise.
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
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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.
Adrian Pöppelwerth, Georg Glebe, Johannes Z. D. Mieth, Florian Koller, Tomas Karlsson, Zoltan Vörös, and Ferdinand Plaschke
Ann. Geophys. Discuss., https://doi.org/10.5194/angeo-2023-31, https://doi.org/10.5194/angeo-2023-31, 2023
Revised manuscript under review for ANGEO
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In the magnetosheath, a near-Earth region of space, we observe increases in plasma velocity and density called jets. As they propagate, the jets disturb the ambient plasma. We study this interaction with three spacecraft simultaneously. Using the plasma motion, we reconstruct the propagation axis and calculate a simple model of the jet shape. We find that the cross section perpendicular to the propagation and the dynamic pressure decrease from the center of the jet to the rear.
Henriette Trollvik, Tomas Karlsson, and Savvas Raptis
Ann. Geophys., 41, 327–337, https://doi.org/10.5194/angeo-41-327-2023, https://doi.org/10.5194/angeo-41-327-2023, 2023
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The solar wind is in a plasma state and can exhibit a range of phenomena like waves and instabilities. One observed phenomenon in the solar wind is magnetic holes (MHs). They are localized depressions in the magnetic field. We studied the motion of MHs using the multispacecraft ESA Cluster mission. We derived their velocities in the solar wind frame and found that both linear and rotational MHs are convected with the solar wind.
Tomas Karlsson, Henriette Trollvik, Savvas Raptis, Hans Nilsson, and Hadi Madanian
Ann. Geophys., 40, 687–699, https://doi.org/10.5194/angeo-40-687-2022, https://doi.org/10.5194/angeo-40-687-2022, 2022
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Magnetic holes are curious localized dropouts of magnetic field strength in the solar wind (the flow of ionized gas continuously streaming out from the sun). In this paper we show that these magnetic holes can cross the bow shock (where the solar wind brake down to subsonic velocity) and enter the region close to Earth’s magnetosphere. These structures may therefore represent a new type of non-uniform solar wind–magnetosphere interaction.
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
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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.
Adnane Osmane, Mikko Savola, Emilia Kilpua, Hannu Koskinen, Joseph E. Borovsky, and Milla Kalliokoski
Ann. Geophys., 40, 37–53, https://doi.org/10.5194/angeo-40-37-2022, https://doi.org/10.5194/angeo-40-37-2022, 2022
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It has long been known that particles get accelerated close to the speed of light in the near-Earth space environment. Research in the last decades has also clarified what processes and waves are responsible for the acceleration of particles. However, it is difficult to quantify the scale of the impact of various processes competing with one another. In this study we present a methodology to quantify the impact waves can have on energetic particles.
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
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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.
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.
Martin Volwerk, David Mautner, Cyril Simon Wedlund, Charlotte Goetz, Ferdinand Plaschke, Tomas Karlsson, Daniel Schmid, Diana Rojas-Castillo, Owen W. Roberts, and Ali Varsani
Ann. Geophys., 39, 239–253, https://doi.org/10.5194/angeo-39-239-2021, https://doi.org/10.5194/angeo-39-239-2021, 2021
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The magnetic field in the solar wind is not constant but varies in direction and strength. One of these variations shows a strong local reduction of the magnetic field strength and is called a magnetic hole. These holes are usually an indication that there is, or has been, a temperature difference in the plasma of the solar wind, with the temperature along the magnetic field lower than perpendicular. The MMS spacecraft data have been used to study the characteristics of these holes near Earth.
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.
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.
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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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.
Emilia K. J. Kilpua, Dominique Fontaine, Simon W. Good, Matti Ala-Lahti, Adnane Osmane, Erika Palmerio, Emiliya Yordanova, Clement Moissard, Lina Z. Hadid, and Miho Janvier
Ann. Geophys., 38, 999–1017, https://doi.org/10.5194/angeo-38-999-2020, https://doi.org/10.5194/angeo-38-999-2020, 2020
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This paper studies magnetic field fluctuations in three turbulent sheath regions ahead of interplanetary coronal mass ejections (ICMEs) in the near-Earth solar wind. Our results show that fluctuation properties vary significantly in different parts of the sheath when compared to solar wind ahead. Turbulence in sheaths resembles that of the slow solar wind in the terrestrial magnetosheath, e.g. regarding compressibility and intermittency, and it often lacks Kolmogorov's spectral indices.
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
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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.
Milla M. H. Kalliokoski, Emilia K. J. Kilpua, Adnane Osmane, Drew L. Turner, Allison N. Jaynes, Lucile Turc, Harriet George, and Minna Palmroth
Ann. Geophys., 38, 683–701, https://doi.org/10.5194/angeo-38-683-2020, https://doi.org/10.5194/angeo-38-683-2020, 2020
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We present a comprehensive statistical study of the response of the Earth's space environment in sheath regions prior to interplanetary coronal mass ejections. The inner magnetospheric wave activity is enhanced in sheath regions, and the sheaths cause significant changes to the outer radiation belt electron fluxes over short timescales. We also show that non-geoeffective sheaths can result in a significant response.
Markus Battarbee, Urs Ganse, Yann Pfau-Kempf, Lucile Turc, Thiago Brito, Maxime Grandin, Tuomas Koskela, and Minna Palmroth
Ann. Geophys., 38, 625–643, https://doi.org/10.5194/angeo-38-625-2020, https://doi.org/10.5194/angeo-38-625-2020, 2020
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The structure and medium-scale dynamics of Earth's bow shock and how charged solar wind particles are reflected by it are studied in order to better understand space weather effects. We use advanced supercomputer simulations to model the shock and reflected ions. We find that the thickness of the shock depends on solar wind conditions but also has small-scale variations. Charged particle reflection is shown to be non-localized. Magnetic fields are important for ion reflection.
Theodoros E. Sarris, Elsayed R. Talaat, Minna Palmroth, Iannis Dandouras, Errico Armandillo, Guram Kervalishvili, Stephan Buchert, Stylianos Tourgaidis, David M. Malaspina, Allison N. Jaynes, Nikolaos Paschalidis, John Sample, Jasper Halekas, Eelco Doornbos, Vaios Lappas, Therese Moretto Jørgensen, Claudia Stolle, Mark Clilverd, Qian Wu, Ingmar Sandberg, Panagiotis Pirnaris, and Anita Aikio
Geosci. Instrum. Method. Data Syst., 9, 153–191, https://doi.org/10.5194/gi-9-153-2020, https://doi.org/10.5194/gi-9-153-2020, 2020
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Daedalus aims to measure the largely unexplored area between Eart's atmosphere and space, the Earth's
ignorosphere. Here, intriguing and complex processes govern the deposition and transport of energy. The aim is to quantify this energy by measuring effects caused by electrodynamic processes in this region. The concept is based on a mother satellite that carries a suite of instruments, along with smaller satellites carrying a subset of instruments that are released into the atmosphere.
Emilia Kilpua, Liisa Juusola, Maxime Grandin, Antti Kero, Stepan Dubyagin, Noora Partamies, Adnane Osmane, Harriet George, Milla Kalliokoski, Tero Raita, Timo Asikainen, and Minna Palmroth
Ann. Geophys., 38, 557–574, https://doi.org/10.5194/angeo-38-557-2020, https://doi.org/10.5194/angeo-38-557-2020, 2020
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Coronal mass ejection sheaths and ejecta are key drivers of significant space weather storms, and they cause dramatic changes in radiation belt electron fluxes. Differences in precipitation of high-energy electrons from the belts to the upper atmosphere are thus expected. We investigate here differences in sheath- and ejecta-induced precipitation using the Finnish riometer (relative ionospheric opacity meter) chain.
Martin Volwerk, Charlotte Goetz, Ferdinand Plaschke, Tomas Karlsson, Daniel Heyner, and Brian Anderson
Ann. Geophys., 38, 51–60, https://doi.org/10.5194/angeo-38-51-2020, https://doi.org/10.5194/angeo-38-51-2020, 2020
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The magnetic field that is carried by the solar wind slowly decreases in strength as it moves further from the Sun. However, there are sometimes localized decreases in the magnetic field strength, called magnetic holes. These are small structures where the magnetic field strength decreases to less than 50 % of the surroundings and the plasma density increases. This paper presents a statistical study of the behaviour of these holes between Mercury and Venus using MESSENGER data.
Maxime Grandin, Markus Battarbee, Adnane Osmane, Urs Ganse, Yann Pfau-Kempf, Lucile Turc, Thiago Brito, Tuomas Koskela, Maxime Dubart, and Minna Palmroth
Ann. Geophys., 37, 791–806, https://doi.org/10.5194/angeo-37-791-2019, https://doi.org/10.5194/angeo-37-791-2019, 2019
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When the terrestrial magnetic field is disturbed, particles from the near-Earth space can precipitate into the upper atmosphere. This work presents, for the first time, numerical simulations of proton precipitation in the energy range associated with the production of aurora (∼1–30 keV) using a global kinetic model of the near-Earth space: Vlasiator. We find that nightside proton precipitation can be regulated by the transition region between stretched and dipolar geomagnetic field lines.
Antti Lakka, Tuija I. Pulkkinen, Andrew P. Dimmock, Emilia Kilpua, Matti Ala-Lahti, Ilja Honkonen, Minna Palmroth, and Osku Raukunen
Ann. Geophys., 37, 561–579, https://doi.org/10.5194/angeo-37-561-2019, https://doi.org/10.5194/angeo-37-561-2019, 2019
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We study how the Earth's space environment responds to two different amplitude interplanetary coronal mass ejection (ICME) events that occurred in 2012 and 2014 by using the GUMICS-4 global MHD model. We examine local and large-scale dynamics of the Earth's space environment and compare simulation results to in situ data. It is shown that during moderate driving simulation agrees well with the measurements; however, GMHD results should be interpreted cautiously during strong driving.
Liisa Juusola, Sanni Hoilijoki, Yann Pfau-Kempf, Urs Ganse, Riku Jarvinen, Markus Battarbee, Emilia Kilpua, Lucile Turc, and Minna Palmroth
Ann. Geophys., 36, 1183–1199, https://doi.org/10.5194/angeo-36-1183-2018, https://doi.org/10.5194/angeo-36-1183-2018, 2018
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The solar wind interacts with the Earth’s magnetic field, forming a magnetosphere. On the night side solar wind stretches the magnetosphere into a long tail. A process called magnetic reconnection opens the magnetic field lines and reconnects them, accelerating particles to high energies. We study this in the magnetotail using a numerical simulation model of the Earth’s magnetosphere. We study the motion of the points where field lines reconnect and the fast flows driven by this process.
Minna Palmroth, Heli Hietala, Ferdinand Plaschke, Martin Archer, Tomas Karlsson, Xóchitl Blanco-Cano, David Sibeck, Primož Kajdič, Urs Ganse, Yann Pfau-Kempf, Markus Battarbee, and Lucile Turc
Ann. Geophys., 36, 1171–1182, https://doi.org/10.5194/angeo-36-1171-2018, https://doi.org/10.5194/angeo-36-1171-2018, 2018
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Magnetosheath jets are high-velocity plasma structures that are commonly observed within the Earth's magnetosheath. Previously, they have mainly been investigated with spacecraft observations, which do not allow us to infer their spatial sizes, temporal evolution, or origin. This paper shows for the first time their dimensions, evolution, and origins within a simulation whose dimensions are directly comparable to the Earth's magnetosphere. The results are compared to previous observations.
Xochitl Blanco-Cano, Markus Battarbee, Lucile Turc, Andrew P. Dimmock, Emilia K. J. Kilpua, Sanni Hoilijoki, Urs Ganse, David G. Sibeck, Paul A. Cassak, Robert C. Fear, Riku Jarvinen, Liisa Juusola, Yann Pfau-Kempf, Rami Vainio, and Minna Palmroth
Ann. Geophys., 36, 1081–1097, https://doi.org/10.5194/angeo-36-1081-2018, https://doi.org/10.5194/angeo-36-1081-2018, 2018
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We use the Vlasiator code to study the characteristics of transient structures that exist in the Earth's foreshock, i.e. upstream of the bow shock. The structures are cavitons and spontaneous hot flow anomalies (SHFAs). These transients can interact with the bow shock. We study the changes the shock suffers via this interaction. We also investigate ion distributions associated with the cavitons and SHFAs. A very important result is that the arrival of multiple SHFAs results in shock erosion.
Liisa Juusola, Yann Pfau-Kempf, Urs Ganse, Markus Battarbee, Thiago Brito, Maxime Grandin, Lucile Turc, and Minna Palmroth
Ann. Geophys., 36, 1027–1035, https://doi.org/10.5194/angeo-36-1027-2018, https://doi.org/10.5194/angeo-36-1027-2018, 2018
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The Earth's magnetic field is shaped by the solar wind. On the dayside the field is compressed and on the nightside it is stretched as a long tail. The tail has been observed to occasionally undergo flapping motions, but the origin of these motions is not understood. We study the flapping using a numerical simulation of the near-Earth space. We present a possible explanation for how the flapping could be initiated by a passing disturbance and then maintained as a standing wave.
Tomas Karlsson, Ferdinand Plaschke, Heli Hietala, Martin Archer, Xóchitl Blanco-Cano, Primož Kajdič, Per-Arne Lindqvist, Göran Marklund, and Daniel J. Gershman
Ann. Geophys., 36, 655–677, https://doi.org/10.5194/angeo-36-655-2018, https://doi.org/10.5194/angeo-36-655-2018, 2018
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We have studied fast plasma jets outside of Earth’s magnetic environment. Such jets are small-scale structures with a limited lifetime, which may be important in determining the properties of the near-Earth space environment, due to their concentrated kinetic energy. We have used data from the NASA Magnetospheric MultiScale (MMS) satellites to study their properties in detail, to understand how these jets are formed. We have found evidence that there are at least two different types of jets.
Minna Palmroth, Sanni Hoilijoki, Liisa Juusola, Tuija I. Pulkkinen, Heli Hietala, Yann Pfau-Kempf, Urs Ganse, Sebastian von Alfthan, Rami Vainio, and Michael Hesse
Ann. Geophys., 35, 1269–1274, https://doi.org/10.5194/angeo-35-1269-2017, https://doi.org/10.5194/angeo-35-1269-2017, 2017
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Much like solar flares, substorms occurring within the Earth's magnetic domain are explosive events that cause vivid auroral displays. A decades-long debate exists to explain the substorm onset. We devise a simulation encompassing the entire near-Earth space and demonstrate that detailed modelling of magnetic reconnection explains the central substorm observations. Our results help to understand the unpredictable substorm process, which will significantly improve space weather forecasts.
Antti Lakka, Tuija I. Pulkkinen, Andrew P. Dimmock, Adnane Osmane, Ilja Honkonen, Minna Palmroth, and Pekka Janhunen
Ann. Geophys., 35, 907–922, https://doi.org/10.5194/angeo-35-907-2017, https://doi.org/10.5194/angeo-35-907-2017, 2017
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We studied the impact on global MHD simulations from different simulation initialisation methods. While the global MHD code used is GUMICS-4 we conclude that the results might be generalisable to other codes as well. It is found that different initialisation methods affect the dynamics of the Earth's space environment by creating differences in momentum transport several hours afterwards. These differences may even grow as a response to rapid solar wind condition changes.
Elisabet Liljeblad and Tomas Karlsson
Ann. Geophys., 35, 879–884, https://doi.org/10.5194/angeo-35-879-2017, https://doi.org/10.5194/angeo-35-879-2017, 2017
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MESSENGER magnetic field data from the magnetosphere of Mercury have been investigated to identify ultra-low-frequency (ULF) waves. ULF waves in the Kelvin–Helmholtz (KH) wave frequency range are frequently observed in the magnetosphere. These ULF waves often have similar characteristics to previously identified, likely KH-driven ULF waves, indicating that ULF waves in a specific frequency band can be used as a detection tool for KH waves on Mercury.
Rikard Slapak, Maria Hamrin, Timo Pitkänen, Masatoshi Yamauchi, Hans Nilsson, Tomas Karlsson, and Audrey Schillings
Ann. Geophys., 35, 869–877, https://doi.org/10.5194/angeo-35-869-2017, https://doi.org/10.5194/angeo-35-869-2017, 2017
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The ion total transports in the near-Earth plasma sheet have been investigated and quantified. Specifically, the net O+ transport is about 1024 s−1 in the earthward direction, which is 1 order of magnitude smaller than the typical O+ ionospheric outflows, strongly indicating that most outflow will eventually escape, leading to significant atmospheric loss. The study also shows that low-velocity flows (< 100 km s−1) dominate the mass transport in the near-Earth plasma sheet.
Yann Pfau-Kempf, Heli Hietala, Steve E. Milan, Liisa Juusola, Sanni Hoilijoki, Urs Ganse, Sebastian von Alfthan, and Minna Palmroth
Ann. Geophys., 34, 943–959, https://doi.org/10.5194/angeo-34-943-2016, https://doi.org/10.5194/angeo-34-943-2016, 2016
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We have simulated the interaction of the solar wind – the charged particles and magnetic fields emitted by the Sun into space – with the magnetic field of the Earth. The solar wind flows supersonically and creates a shock when it encounters the obstacle formed by the geomagnetic field. We have identified a new chain of events which causes phenomena in the downstream region to eventually cause perturbations at the shock and even upstream. This is confirmed by ground and satellite observations.
P. T. Verronen, M. E. Andersson, A. Kero, C.-F. Enell, J. M. Wissing, E. R. Talaat, K. Kauristie, M. Palmroth, T. E. Sarris, and E. Armandillo
Ann. Geophys., 33, 381–394, https://doi.org/10.5194/angeo-33-381-2015, https://doi.org/10.5194/angeo-33-381-2015, 2015
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Electron concentrations observed by EISCAT radars can be reasonable well represented using AIMOS v1.2 satellite-data-based ionization model and SIC D-region ion chemistry model. SIC-EISCAT difference varies from event to event, probably because the statistical nature of AIMOS ionization is not capturing all the spatio-temporal fine structure of electron precipitation. Below 90km, AIMOS overestimates electron ionization because of proton contamination of the satellite electron detectors.
L. Turc, D. Fontaine, P. Savoini, and E. K. J. Kilpua
Ann. Geophys., 32, 1247–1261, https://doi.org/10.5194/angeo-32-1247-2014, https://doi.org/10.5194/angeo-32-1247-2014, 2014
H. Gunell, G. Stenberg Wieser, M. Mella, R. Maggiolo, H. Nilsson, F. Darrouzet, M. Hamrin, T. Karlsson, N. Brenning, J. De Keyser, M. André, and I. Dandouras
Ann. Geophys., 32, 991–1009, https://doi.org/10.5194/angeo-32-991-2014, https://doi.org/10.5194/angeo-32-991-2014, 2014
L. Turc, D. Fontaine, P. Savoini, and E. K. J. Kilpua
Ann. Geophys., 32, 157–173, https://doi.org/10.5194/angeo-32-157-2014, https://doi.org/10.5194/angeo-32-157-2014, 2014
D. Pokhotelov, S. von Alfthan, Y. Kempf, R. Vainio, H. E. J. Koskinen, and M. Palmroth
Ann. Geophys., 31, 2207–2212, https://doi.org/10.5194/angeo-31-2207-2013, https://doi.org/10.5194/angeo-31-2207-2013, 2013
P. Kajdič, X. Blanco-Cano, N. Omidi, K. Meziane, C. T. Russell, J.-A. Sauvaud, I. Dandouras, and B. Lavraud
Ann. Geophys., 31, 2163–2178, https://doi.org/10.5194/angeo-31-2163-2013, https://doi.org/10.5194/angeo-31-2163-2013, 2013
A. T. Aikio, T. Pitkänen, I. Honkonen, M. Palmroth, and O. Amm
Ann. Geophys., 31, 1021–1034, https://doi.org/10.5194/angeo-31-1021-2013, https://doi.org/10.5194/angeo-31-1021-2013, 2013
L. Turc, D. Fontaine, P. Savoini, H. Hietala, and E. K. J. Kilpua
Ann. Geophys., 31, 1011–1019, https://doi.org/10.5194/angeo-31-1011-2013, https://doi.org/10.5194/angeo-31-1011-2013, 2013
Related subject area
Subject: Magnetosphere & space plasma physics | Keywords: Magnetosheath
Scalar-potential mapping of the steady-state magnetosheath model
Local bow shock environment during magnetosheath jet formation: results from a hybrid-Vlasov simulation
Statistical distribution of mirror-mode-like structures in the magnetosheaths of unmagnetized planets – Part 2: Venus as observed by the Venus Express spacecraft
Magnetosheath plasma flow model around Mercury
Asymmetries in the Earth's dayside magnetosheath: results from global hybrid-Vlasov simulations
On the alignment of velocity and magnetic fields within magnetosheath jets
Jets in the magnetosheath: IMF control of where they occur
Magnetosheath jet properties and evolution as determined by a global hybrid-Vlasov simulation
Yasuhito Narita, Daniel Schmid, and Simon Toepfer
Ann. Geophys., 42, 79–89, https://doi.org/10.5194/angeo-42-79-2024, https://doi.org/10.5194/angeo-42-79-2024, 2024
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The magnetosheath is a transition layer surrounding the planetary magnetosphere. We develop an algorithm to compute the plasma flow velocity and magnetic field for a more general shape of magnetosheath using the concept of potential field and suitable coordinate transformation. Application to the empirical Earth magnetosheath region is shown in the paper. The developed algorithm is useful when interpreting the spacecraft data or simulation of the planetary magnetosheath region.
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.
Martin Volwerk, Cyril Simon Wedlund, David Mautner, Sebastián Rojas Mata, Gabriella Stenberg Wieser, Yoshifumi Futaana, Christian Mazelle, Diana Rojas-Castillo, César Bertucci, and Magda Delva
Ann. Geophys., 41, 389–408, https://doi.org/10.5194/angeo-41-389-2023, https://doi.org/10.5194/angeo-41-389-2023, 2023
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Freshly created ions in solar wind start gyrating around the interplanetary magnetic field. When they cross the bow shock, they get an extra kick, and this increases the plasma pressure against the magnetic pressure. This leads to the creation of so-called mirror modes, regions where the magnetic field decreases in strength and the plasma density increases. These structures help in exploring how energy is transferred from the ions to the magnetic field and where around Venus this is happening.
Daniel Schmid, Yasuhito Narita, Ferdinand Plaschke, Martin Volwerk, Rumi Nakamura, and Wolfgang Baumjohann
Ann. Geophys., 39, 563–570, https://doi.org/10.5194/angeo-39-563-2021, https://doi.org/10.5194/angeo-39-563-2021, 2021
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In this work we present the first analytical magnetosheath plasma flow model for the space environment around Mercury. The proposed model is relatively simple to implement and provides the possibility to trace the flow lines inside the Hermean magnetosheath. It can help to determine the the local plasma conditions of a spacecraft in the magnetosheath exclusively on the basis of the upstream solar wind parameters.
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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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.
Ferdinand Plaschke, Maria Jernej, Heli Hietala, and Laura Vuorinen
Ann. Geophys., 38, 287–296, https://doi.org/10.5194/angeo-38-287-2020, https://doi.org/10.5194/angeo-38-287-2020, 2020
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Jets of solar-wind plasma commonly hit the Earth's magnetosphere. Using data from the four Magnetospheric Multiscale (MMS) spacecraft, we show statistically that within jets the magnetic field is more aligned with the plasma flow direction than outside of these jets. Our study confirms prior simulation results, but it also shows that the average effect is moderate. The jets' magnetic field is important with respect to their impact on space weather.
Laura Vuorinen, Heli Hietala, and Ferdinand Plaschke
Ann. Geophys., 37, 689–697, https://doi.org/10.5194/angeo-37-689-2019, https://doi.org/10.5194/angeo-37-689-2019, 2019
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Before the solar wind encounters the Earth's magnetic field, it is first slowed down and deflected by the Earth's bow shock. We find that downstream of the bow shock regions where the shock normal and the solar wind magnetic field are almost parallel and the shock is more rippled, plasma jets with high earthward velocities are observed significantly more often than elsewhere downstream of the shock. Our results help us forecast the occurrence of these jets and their effects on Earth.
Minna Palmroth, Heli Hietala, Ferdinand Plaschke, Martin Archer, Tomas Karlsson, Xóchitl Blanco-Cano, David Sibeck, Primož Kajdič, Urs Ganse, Yann Pfau-Kempf, Markus Battarbee, and Lucile Turc
Ann. Geophys., 36, 1171–1182, https://doi.org/10.5194/angeo-36-1171-2018, https://doi.org/10.5194/angeo-36-1171-2018, 2018
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Magnetosheath jets are high-velocity plasma structures that are commonly observed within the Earth's magnetosheath. Previously, they have mainly been investigated with spacecraft observations, which do not allow us to infer their spatial sizes, temporal evolution, or origin. This paper shows for the first time their dimensions, evolution, and origins within a simulation whose dimensions are directly comparable to the Earth's magnetosphere. The results are compared to previous observations.
Cited articles
Archer, M. O., Horbury, T. S., and Eastwood, J. P.: Magnetosheath pressure pulses: Generation downstream of the bow shock from solar wind discontinuities, J. Geophys. Res.-Space, 117, A05228, https://doi.org/10.1029/2011JA017468, 2012. a
Archer, M. O., Hietala, H., Hartinger, M. D., Plaschke, F., and Angelopoulos, V.: Direct observations of a surface eigenmode of the dayside magnetopause, Nat. Commun., 10, 615, https://doi.org/10.1038/s41467-018-08134-5, 2019. a
Battarbee, M. and the Vlasiator team: Analysator: python analysis toolkit, Zenodo, https://doi.org/10.5281/zenodo.4462515, 2020. a
Battarbee, M., Ganse, U., Pfau-Kempf, Y., Turc, L., Brito, T., Grandin, M., Koskela, T., and Palmroth, M.: Non-locality of Earth's quasi-parallel bow shock: injection of thermal protons in a hybrid-Vlasov simulation, Ann. Geophys., 38, 625–643, https://doi.org/10.5194/angeo-38-625-2020, 2020. a, b
Battarbee, M., Brito, T., Alho, M., Pfau-Kempf, Y., Grandin, M., Ganse, U.,
Papadakis, K., Johlander, A., Turc, L., Dubart, M., and Palmroth, M.: Vlasov
simulation of electrons in the context of hybrid global models: an eVlasiator
approach, Ann. Geophys., 39, 85–103, https://doi.org/10.5194/angeo-39-85-2021, 2021. a
Blanco-Cano, X., Omidi, N., and Russell, C. T.: Macrostructure of collisionless bow shocks: 2. ULF waves in the foreshock and magnetosheath, J. Geophys. Res.-Space, 111, A10205, https://doi.org/10.1029/2005JA011421, 2006. a
Burch, J. L., Moore, T. E., Torbert, R. B., and Giles, B. L.: Magnetospheric Multiscale Overview and Science Objectives, Space Sci. Rev., 199, 5–21, https://doi.org/10.1007/s11214-015-0164-9, 2016. a, b
Burgess, D.: Foreshock-shock interaction at collisionless quasi-parallel shocks, Proceedings of the D2.1 Symposium of COSPAR Scientific Commission D, Adv. Space Res., 15, 159–169, https://doi.org/10.1016/0273-1177(94)00098-L, 1995. a
Dimmock, A. P. and Nykyri, K.: The statistical mapping of magnetosheath plasma properties based on THEMIS measurements in the magnetosheath interplanetary medium reference frame, J. Geophys. Res.-Space, 118, 4963–4976, https://doi.org/10.1002/jgra.50465, 2013. a
Dimmock, A. P., Nykyri, K., and Pulkkinen, T. I.: A statistical study of magnetic field fluctuations in the dayside magnetosheath and their dependence on upstream solar wind conditions, J. Geophys. Res.-Space, 119, 6231–6248, https://doi.org/10.1002/2014JA020009, 2014. a
Dimmock, A. P., Osmane, A., Pulkkinen, T. I., and Nykyri, K.: A statistical study of the dawn-dusk asymmetry of ion temperature anisotropy and mirror mode occurrence in the terrestrial dayside magnetosheath using THEMIS data, J. Geophys. Res.-Space, 120, 5489–5503, https://doi.org/10.1002/2015JA021192, 2015. a
Dimmock, A. P., Osmane, A., Pulkkinen, T. I., Nykyri, K., and Kilpua, E.: Temperature variations in the dayside magnetosheath and their dependence on ion-scale magnetic structures: THEMIS statistics and measurements by MMS, J. Geophys. Res.-Space, 122, 6165–6184, https://doi.org/10.1002/2016JA023729, 2017. a
Dubart, M., Ganse, U., Osmane, A., Johlander, A., Battarbee, M., Grandin, M., Pfau-Kempf, Y., Turc, L., and Palmroth, M.: Resolution dependence of magnetosheath waves in global hybrid-Vlasov simulations, Ann. Geophys., 38, 1283–1298, https://doi.org/10.5194/angeo-38-1283-2020, 2020. a, b
Eastwood, J. P., Lucek, E. A., Mazelle, C., Meziane, K., Narita, Y., Pickett, J., and Treumann, R. A.: The Foreshock, Space Sci. Rev., 118, 41–94, https://doi.org/10.1007/s11214-005-3824-3, 2005. a
Génot, V., Budnik, E., Hellinger, P., Passot, T., Belmont, G., Trávníček, P. M., Sulem, P.-L., Lucek, E., and Dandouras, I.: Mirror structures above and below the linear instability threshold: Cluster observations, fluid model and hybrid simulations, Ann. Geophys., 27, 601–615, https://doi.org/10.5194/angeo-27-601-2009, 2009. a
Hietala, H., Laitinen, T. V., Andréeová, K., Vainio, R., Vaivads, A., Palmroth, M., Pulkkinen, T. I., Koskinen, H. E. J., Lucek, E. A., and Rème, H.: Supermagnetosonic Jets behind a Collisionless Quasiparallel Shock, Phys. Rev. Lett., 103, 245001, https://doi.org/10.1103/PhysRevLett.103.245001, 2009. a
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., Palmroth, M., Walsh, B. M., Pfau-Kempf, Y., von Alfthan, S., Ganse, U., Hannuksela, O., and Vainio, R.: Mirror modes in the Earth's magnetosheath: Results from a global hybrid-Vlasov simulation, J. Geophys. Res.-Space, 121, 4191–4204, https://doi.org/10.1002/2015JA022026, 2016. a
Jarvinen, R., Vainio, R., Palmroth, M., Juusola, L., Hoilijoki, S., Pfau-Kempf, Y., Ganse, U., Turc, L., and von Alfthan, S.: Ion Acceleration by Flux Transfer Events in the Terrestrial Magnetosheath, Geophys. Res. Lett., 45, 1723–1731, https://doi.org/10.1002/2017GL076192, 2018. a
Karimabadi, H., Roytershteyn, V., Vu, H. X., Omelchenko, Y. A., Scudder, J., Daughton, W., Dimmock, A., Nykyri, K., Wan, M., Sibeck, D., Tatineni, M., Majumdar, A., Loring, B., and Geveci, B.: The link between shocks, turbulence, and magnetic reconnection in collisionless plasmas, Phys. Plasmas, 21, 062308, https://doi.org/10.1063/1.4882875, 2014. a
Karlsson, T., Kullen, A., Liljeblad, E., Brenning, N., Nilsson, H., Gunell, H., and Hamrin, M.: On the origin of magnetosheath plasmoids and their relation to magnetosheath jets, J. Geophys. Res.-Space, 120, 7390–7403, https://doi.org/10.1002/2015JA021487, 2015. a, b, c
Kempf, Y., Pokhotelov, D., Gutynska, O., Wilson III, L. B., Walsh, B. M., Alfthan, S. v., Hannuksela, O., Sibeck, D. G., and Palmroth, M.: Ion distributions in the Earth's foreshock: Hybrid-Vlasov simulation and THEMIS observations, J. Geophys. Res.-Space, 120, 3684–3701, https://doi.org/10.1002/2014JA020519, 2015. a
King, J. H. and Papitashvili, N. E.: Solar wind spatial scales in and comparisons of hourly Wind and ACE plasma and magnetic field data, J. Geophys. Res.-Space, 110, A02104, https://doi.org/10.1029/2004JA010649, 2005. a
Lucek, E. A., Horbury, T. S., Dunlop, M. W., Cargill, P. J., Schwartz, S. J., Balogh, A., Brown, P., Carr, C., Fornacon, K.-H., and Georgescu, E.: Cluster magnetic field observations at a quasi-parallel bow shock, Ann. Geophys., 20, 1699–1710, https://doi.org/10.5194/angeo-20-1699-2002, 2002. a
Lucek, E. A., Constantinescu, D., Goldstein, M. L., Pickett, J., Pinçon, J. L., Sahraoui, F., Treumann, R. A., and Walker, S. N.: The Magnetosheath, Space Sci. Rev., 118, 95–152, https://doi.org/10.1007/s11214-005-3825-2, 2005. a
Merka, J., Szabo, A., Slavin, J. A., and Peredo, M.: Three-dimensional position and shape of the bow shock and their variation with upstream Mach numbers and interplanetary magnetic field orientation, J. Geophys. Res.-Space, 110, A04202, https://doi.org/10.1029/2004JA010944, 2005. a
NASA: OMNIweb, available at: https://omniweb.gsfc.nasa.gov, last access: 9 March 2021. a
Němeček, Z., Šafránková, J., Přech, L., Sibeck, D. G., Kokubun, S., and Mukai, T.: Transient flux enhancements in the magnetosheath, Geophys. Res. Lett., 25, 1273–1276, https://doi.org/10.1029/98GL50873, 1998. a
Němeček, Z., Šafránková, J., Zastenker, G. N., Pišoft, P., and Jelínek, K.: Low-frequency variations of the ion flux in the magnetosheath, Planet. Space Sci., 50, 567–575, https://doi.org/10.1016/S0032-0633(02)00036-3, 2002. a
Omidi, N., Berchem, J., Sibeck, D., and Zhang, H.: Impacts of spontaneous hot flow anomalies on the magnetosheath and magnetopause, J. Geophys. Res.-Space, 121, 3155–3169, https://doi.org/10.1002/2015JA022170, 2016. a
Palmroth, M.: Vlasiator, available at: http://www.physics.helsinki.fi/vlasiator/, last access: 9 March 2021. a
Palmroth, M. and the Vlasiator team: Vlasiator: hybrid-Vlasov simulation code, Github repository, https://doi.org/10.5281/zenodo.3640593, version 5.0, 2020. a
Palmroth, M., Honkonen, I., Sandroos, A., Kempf, Y., von Alfthan, S., and Pokhotelov, D.: Preliminary testing of global hybrid-Vlasov simulation: Magnetosheath and cusps under northward interplanetary magnetic field, J. Atmos. Sol.-Terr. Phy., 99, 41–46, https://doi.org/10.1016/j.jastp.2012.09.013, 2013. a
Palmroth, M., Archer, M., Vainio, R., Hietala, H., Pfau-Kempf, Y., Hoilijoki, S., Hannuksela, O., Ganse, U., Sandroos, A., Alfthan, S. v., and Eastwood, J. P.: ULF foreshock under radial IMF: THEMIS observations and global kinetic simulation Vlasiator results compared, J. Geophys. Res.-Space, 120, 8782–8798, https://doi.org/10.1002/2015JA021526, 2015. a
Palmroth, M., Hietala, H., Plaschke, F., Archer, M., Karlsson, T., Blanco-Cano, X., Sibeck, D., Kajdič, P., Ganse, U., Pfau-Kempf, Y., Battarbee, M., and Turc, L.: Magnetosheath jet properties and evolution as determined by a global hybrid-Vlasov simulation, Ann. Geophys., 36, 1171–1182, https://doi.org/10.5194/angeo-36-1171-2018, 2018a. a, b, c, d, e, f, g, h, i
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, 2018b. a
Petrinec, S. M.: On the magnetic field configuration of the magnetosheath, Terr. Atmos. Ocean. Sci., 24, 265–272, https://doi.org/10.3319/TAO.2012.10.17.02(SEC), 2013. a
Pfau-Kempf, Y., Battarbee, M., Ganse, U., Hoilijoki, S., Turc, L., von Alfthan, S., Vainio, R., and Palmroth, M.: On the Importance of Spatial and Velocity Resolution in the Hybrid-Vlasov Modeling of Collisionless Shocks, Front. Phys., 6, 44, https://doi.org/10.3389/fphy.2018.00044, 2018. a
Plaschke, F., Hietala, H., Angelopoulos, V., and Nakamura, R.: Geoeffective jets impacting the magnetopause are very common, J. Geophys. Res.-Space, 121, 3240–3253, https://doi.org/10.1002/2016JA022534, 2016. a, b
Plaschke, F., Hietala, H., Archer, M., Blanco-Cano, X., Kajdič, P., Karlsson, T., Lee, S. H., Omidi, N., Palmroth, M., Roytershteyn, V., Schmid, D., Sergeev, V., and Sibeck, D.: Jets Downstream of Collisionless Shocks, Space Sci. Rev., 214, 81, https://doi.org/10.1007/s11214-018-0516-3, 2018. a, b
Plaschke, F., Hietala, H., and Vörös, Z.: Scale Sizes of Magnetosheath Jets, J. Geophys. Res.-Space, 125, e2020JA027962, https://doi.org/10.1029/2020JA027962, 2020. a
Pollock, C., Moore, T., Jacques, A., Burch, J., Gliese, U., Saito, Y., Omoto, T., Avanov, L., Barrie, A., Coffey, V., Dorelli, J., Gershman, D., Giles, B., Rosnack, T., Salo, C., Yokota, S., Adrian, M., Aoustin, C., Auletti, C., Aung, S., Bigio, V., Cao, N., Chandler, M., Chornay, D., Christian, K., Clark, G., Collinson, G., Corris, T., De Los Santos, A., Devlin, R., Diaz, T., Dickerson, T., Dickson, C., Diekmann, A., Diggs, F., Duncan, C., Figueroa-Vinas, A., Firman, C., Freeman, M., Galassi, N., Garcia, K., Goodhart, G., Guererro, D., Hageman, J., Hanley, J., Hemminger, E., Holland, M., Hutchins, M., James, T., Jones, W., Kreisler, S., Kujawski, J., Lavu, V., Lobell, J., LeCompte, E., Lukemire, A., MacDonald, E., Mariano, A., Mukai, T., Narayanan, K., Nguyan, Q., Onizuka, M., Paterson, W., Persyn, S., Piepgrass, B., Cheney, F., Rager, A., Raghuram, T., Ramil, A., Reichenthal, L., Rodriguez, H., Rouzaud, J., Rucker, A., Saito, Y., Samara, M., Sauvaud, J.-A., Schuster, D., Shappirio, M., Shelton, K., Sher, D., Smith, D., Smith, K., Smith, S., Steinfeld, D., Szymkiewicz, R., Tanimoto, K., Taylor, J., Tucker, C., Tull, K., Uhl, A., Vloet, J., Walpole, P., Weidner, S., White, D., Winkert, G., Yeh, P.-S., and Zeuch, M.: Fast Plasma Investigation for Magnetospheric Multiscale, Space Sci. Rev., 199, 331–406, https://doi.org/10.1007/s11214-016-0245-4, 2016. a
Raptis, S., Karlsson, T., Plaschke, F., Kullen, A., and Lindqvist, P.-A.:
Classifying Magnetosheath Jets using MMS – Statistical Properties,
J. Geophys. Res.-Space, 125, e2019JA027754, https://doi.org/10.1029/2019JA027754,
2020. a, b
Russell, C. T., Anderson, B. J., Baumjohann, W., Bromund, K. R., Dearborn, D., Fischer, D., Le, G., Leinweber, H. K., Leneman, D., Magnes, W., Means, J. D., Moldwin, M. B., Nakamura, R., Pierce, D., Plaschke, F., Rowe, K. M., Slavin, J. A., Strangeway, R. J., Torbert, R., Hagen, C., Jernej, I., Valavanoglou, A., and Richter, I.: The Magnetospheric Multiscale Magnetometers, Space Sci. Rev., 199, 189–256, https://doi.org/10.1007/s11214-014-0057-3, 2016. a
Sandroos, A.: VLSV: file format and tools, Github repository, available at: https://github.com/fmihpc/vlsv/ (last access: 9 March 2021), 2019. a
Schwartz, S. J., Thomsen, M. F., and Gosling, J. T.: Ions upstream of the Earth's bow shock: A theoretical comparison of alternative source populations, J. Geophys. Res.-Space, 88, 2039–2047, https://doi.org/10.1029/JA088iA03p02039, 1983. a
Schwartz, S. J., Burgess, D., and Moses, J. J.: Low-frequency waves in the Earth's magnetosheath: present status, Ann. Geophys., 14, 1134–1150, https://doi.org/10.1007/s00585-996-1134-z, 1996. a
Shevyrev, N. N., Zastenker, G. N., and Du, J.: Statistics of low-frequency variations in solar wind, foreshock and magnetosheath: INTERBALL-1 and CLUSTER data, Planet. Space Sci., 55, 2330–2335, https://doi.org/10.1016/j.pss.2007.05.014, 2007. a
Shue, J. H., Song, P., Russell, C. T., Steinberg, J. T., Chao, J. K., Zastenker, G., Vaisberg, O. L., Kokubun, S., Singer, H. J., Detman, T. R., and Kawano, H.: Magnetopause location under extreme solar wind conditions, J. Geophys. Res., 103, 17691–17700, https://doi.org/10.1029/98JA01103, 1998. a
Soucek, J., Escoubet, C. P., and Grison, B.: Magnetosheath plasma stability and ULF wave occurrence as a function of location in the magnetosheath and upstream bow shock parameters, J. Geophys. Res.-Space, 120, 2838–2850, https://doi.org/10.1002/2015JA021087, 2015. a
Stahara, S. S.: Adventures in the magnetosheath: two decades of modeling and planetary applications of the Spreiter magnetosheath model, Planet. Space Sci., 50, 421–442, https://doi.org/10.1016/S0032-0633(02)00023-5, 2002. a
Turc, L., Fontaine, D., Escoubet, C. P., Kilpua, E. K. J., and Dimmock, A. P.: Statistical study of the alteration of the magnetic structure of magnetic clouds in the Earth's magnetosheath, J. Geophys. Res.-Space, 122, 2956–2972, https://doi.org/10.1002/2016JA023654, 2017. a
Turc, L., Ganse, U., Pfau-Kempf, Y., Hoilijoki, S., Battarbee, M., Juusola, L., Jarvinen, R., Brito, T., Grandin, M., and Palmroth, M.: Foreshock Properties at Typical and Enhanced Interplanetary Magnetic Field Strengths: Results From Hybrid-Vlasov Simulations, J. Geophys. Res.-Space, 123, 5476–5493, https://doi.org/10.1029/2018JA025466, 2018.
a
Turc, L., Roberts, O. W., Archer, M. O., Palmroth, M., Battarbee, M., Brito, T., Ganse, U., Grandin, M., Pfau-Kempf, Y., Escoubet, C. P., and Dandouras, I.: First Observations of the Disruption of the Earth's Foreshock Wave Field During Magnetic Clouds, Geophys. Res. Lett., 46, 12644–12653, https://doi.org/10.1029/2019GL084437, 2019. a, b
Voitcu, G. and Echim, M.: Transport and entry of plasma clouds/jets across transverse magnetic discontinuities: Three-dimensional electromagnetic particle-in-cell simulations, J. Geophys. Res.-Space, 121, 4343–4361, https://doi.org/10.1002/2015JA021973, 2016. a
Voitcu, G. and Echim, M.: Crescent-shaped electron velocity distribution functions formed at the edges of plasma jets interacting with a tangential discontinuity, Ann. Geophys., 36, 1521–1535, https://doi.org/10.5194/angeo-36-1521-2018, 2018. 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
Vuorinen, L., Hietala, H., and Plaschke, F.: Jets in the magnetosheath: IMF control of where they occur, Ann. Geophys., 37, 689–697, https://doi.org/10.5194/angeo-37-689-2019, 2019. a
Walsh, B. M., Sibeck, D. G., Wang, Y., and Fairfield, D. H.: Dawn-dusk asymmetries in the Earth's magnetosheath, J. Geophys. Res.-Space, 117, A12211, https://doi.org/10.1029/2012JA018240, 2012. a
Winterhalter, D. and Kivelson, M. G.: Observations of the Earth's bow shock under high Mach number/high plasma beta solar wind conditions, Geophys. Res. Lett., 15, 1161–1164, https://doi.org/10.1029/GL015i010p01161, 1988. a
Zastenker, G. N., Nozdrachev, M. N., Němeček, Z., Šafránková, J., Paularena, K. I., Richardson, J. D., Lepping, R. P., and Mukai, T.: Multispacecraft measurements of plasma and magnetic field variations in the magnetosheath: Comparison with Spreiter models and motion of the structures, Planet. Space Sci., 50, 601–612, https://doi.org/10.1016/S0032-0633(02)00039-9, 2002. a
Short summary
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.
Magnetosheath jets are high-velocity features within the Earth's turbulent magnetosheath,...
