Articles | Volume 38, issue 4
https://doi.org/10.5194/angeo-38-931-2020
© Author(s) 2020. 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-38-931-2020
© Author(s) 2020. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Regular paper
| 
28 Aug 2020
Regular paper |
| 28 Aug 2020
| 28 Aug 2020
Outer Van Allen belt trapped and precipitating electron flux responses to two interplanetary magnetic clouds of opposite polarity
Harriet George
CORRESPONDING AUTHOR
Department of Physics, University of Helsinki, Helsinki, Finland
Emilia Kilpua
Department of Physics, University of Helsinki, Helsinki, Finland
Adnane Osmane
Department of Physics, University of Helsinki, Helsinki, Finland
Timo Asikainen
Department of Physics, University of Oulu, Oulu, Finland
Milla M. H. Kalliokoski
Department of Physics, University of Helsinki, Helsinki, Finland
Craig J. Rodger
Department of Physics, University of Otago, Dunedin, New Zealand
Stepan Dubyagin
Finnish Meteorological Institute, Helsinki, Finland
Minna Palmroth
Department of Physics, University of Helsinki, Helsinki, Finland
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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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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.
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Ann. Geophys. Discuss., https://doi.org/10.5194/angeo-2024-3, https://doi.org/10.5194/angeo-2024-3, 2024
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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.
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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.
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.
Ioannis A. Daglis, Loren C. Chang, Sergio Dasso, Nat Gopalswamy, Olga V. Khabarova, Emilia Kilpua, Ramon Lopez, Daniel Marsh, Katja Matthes, Dibyendu Nandy, Annika Seppälä, Kazuo Shiokawa, Rémi Thiéblemont, and Qiugang Zong
Ann. Geophys., 39, 1013–1035, https://doi.org/10.5194/angeo-39-1013-2021, https://doi.org/10.5194/angeo-39-1013-2021, 2021
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We present a detailed account of the science programme PRESTO (PREdictability of the variable Solar–Terrestrial cOupling), covering the period 2020 to 2024. PRESTO was defined by a dedicated committee established by SCOSTEP (Scientific Committee on Solar-Terrestrial Physics). We review the current state of the art and discuss future studies required for the most effective development of solar–terrestrial physics.
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, 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.
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.
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.
Matti M. Ala-Lahti, Emilia K. J. Kilpua, Andrew P. Dimmock, Adnane Osmane, Tuija Pulkkinen, and Jan Souček
Ann. Geophys., 36, 793–808, https://doi.org/10.5194/angeo-36-793-2018, https://doi.org/10.5194/angeo-36-793-2018, 2018
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We present a comprehensive statistical analysis of mirror mode waves and the properties of their plasma surroundings in sheath regions driven by interplanetary coronal mass ejection (ICME) to deepen our understanding of these geo-effective plasma environments. The results imply that mirror modes are common structures in ICME sheaths and occur almost exclusively as dip-like structures and in mirror stable stable plasma.
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.
Israel Silber, Colin Price, and Craig J. Rodger
Atmos. Chem. Phys., 16, 3279–3288, https://doi.org/10.5194/acp-16-3279-2016, https://doi.org/10.5194/acp-16-3279-2016, 2016
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We report for the first time that the semi-annual oscillation (SAO) is one of the dominant oscillations in the nighttime lower ionosphere, using ground-based measurements of VLF signals reflected off the lower part of the ionosphere. We conclude that the origins of this oscillation are oscillatory changes of the D region's electrical characteristics, driven by NOx transport from the lower thermosphere. This oscillation should be considered in lower ionospheric and VLF wave propagation models.
Erika Palmerio, Emilia K. J. Kilpua, and Neel P. Savani
Ann. Geophys., 34, 313–322, https://doi.org/10.5194/angeo-34-313-2016, https://doi.org/10.5194/angeo-34-313-2016, 2016
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Coronal Mass Ejections (CMEs) are giant clouds of plasma and magnetic field that erupt from the Sun and travel though the solar wind. They can cause interplanetary shocks in the vicinity of Earth. We show in our paper that the region that follows CME-driven shocks, known as sheath region, can obtain a planar configuration of the magnetic field lines (planar magnetic structure, PMS) due to the compression resulting from the shock itself or from the draping of the magnetic field ahead of the CME.
M. Myllys, E. Kilpua, and T. Pulkkinen
Ann. Geophys., 33, 845–855, https://doi.org/10.5194/angeo-33-845-2015, https://doi.org/10.5194/angeo-33-845-2015, 2015
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.
K. Andréeová, L. Juusola, E. K. J. Kilpua, and H. E. J. Koskinen
Ann. Geophys., 32, 1293–1302, https://doi.org/10.5194/angeo-32-1293-2014, https://doi.org/10.5194/angeo-32-1293-2014, 2014
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
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
M. E. Andersson, P. T. Verronen, C. J. Rodger, M. A. Clilverd, and S. Wang
Atmos. Chem. Phys., 14, 1095–1105, https://doi.org/10.5194/acp-14-1095-2014, https://doi.org/10.5194/acp-14-1095-2014, 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
E. K. J. Kilpua, H. Hietala, H. E. J. Koskinen, D. Fontaine, and L. Turc
Ann. Geophys., 31, 1559–1567, https://doi.org/10.5194/angeo-31-1559-2013, https://doi.org/10.5194/angeo-31-1559-2013, 2013
E. K. J. Kilpua, A. Isavnin, A. Vourlidas, H. E. J. Koskinen, and L. Rodriguez
Ann. Geophys., 31, 1251–1265, https://doi.org/10.5194/angeo-31-1251-2013, https://doi.org/10.5194/angeo-31-1251-2013, 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
K. Andreeova, E. K. J. Kilpua, H. Hietala, H. E. J. Koskinen, A. Isavnin, and R. Vainio
Ann. Geophys., 31, 555–562, https://doi.org/10.5194/angeo-31-555-2013, https://doi.org/10.5194/angeo-31-555-2013, 2013
S. Dubyagin, N. Ganushkina, S. Apatenkov, M. Kubyshkina, H. Singer, and M. Liemohn
Ann. Geophys., 31, 395–408, https://doi.org/10.5194/angeo-31-395-2013, https://doi.org/10.5194/angeo-31-395-2013, 2013
Related subject area
Subject: Magnetosphere & space plasma physics | Keywords: Radiation belts
Comparison of radiation belt electron fluxes simultaneously measured with PROBA-V/EPT and RBSP/MagEIS instruments
Electron radiation belt safety indices based on the SafeSpace modelling pipeline and dedicated to the internal charging risk
The “SafeSpace” database of ULF power spectral density and radial diffusion coefficients: dependencies and application to simulations
Quantifying the non-linear dependence of energetic electron fluxes in the Earth's radiation belts with radial diffusion drivers
On the semi-annual variation of relativistic electrons in the outer radiation belt
Seasonal dependence of the Earth's radiation belt – new insights
Distribution of Earth's radiation belts' protons over the drift frequency of particles
Outer radiation belt and inner magnetospheric response to sheath regions of coronal mass ejections: a statistical analysis
Energetic electron enhancements under the radiation belt (L < 1.2) during a non-storm interval on 1 August 2008
GREEN: the new Global Radiation Earth ENvironment model (beta version)
Van Allen Probes observation of plasmaspheric hiss modulated by injected energetic electrons
Alexandre Winant, Viviane Pierrard, and Edith Botek
Ann. Geophys., 41, 313–325, https://doi.org/10.5194/angeo-41-313-2023, https://doi.org/10.5194/angeo-41-313-2023, 2023
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In this work, we analyzed and compared measurements of electron fluxes in the radiation belts from two instruments with different orbits. In the outer belt, where the altitude difference is the largest between the two instruments, we find that the observations are in good agreement, except during geomagnetic storms, during which fluxes at low altitudes are much lower than at high altitudes. In general, both at low and high altitudes, the correlation between the instruments was found to be good.
Nour Dahmen, Antoine Brunet, Sebastien Bourdarie, Christos Katsavrias, Guillerme Bernoux, Stefanos Doulfis, Afroditi Nasi, Ingmar Sandberg, Constantinos Papadimitriou, Jesus Oliveros Fernandez, and Ioannis Daglis
Ann. Geophys., 41, 301–312, https://doi.org/10.5194/angeo-41-301-2023, https://doi.org/10.5194/angeo-41-301-2023, 2023
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Earth’s space environment is populated with charged particles. The energetic ones are trapped around Earth in radiation belts. Orbiting spacecraft that cross their region can accumulate charges on their internal surfaces, leading to hazardous electrostatic discharges. This paper showcases the SafeSpace safety prototype, which aims to warn satellite operators of probable incoming hazardous events by simulating the dynamics of the electron radiation belts from their origin at the Sun.
Christos Katsavrias, Afroditi Nasi, Ioannis A. Daglis, Sigiava Aminalragia-Giamini, Nourallah Dahmen, Constantinos Papadimitriou, Marina Georgiou, Antoine Brunet, and Sebastien Bourdarie
Ann. Geophys., 40, 379–393, https://doi.org/10.5194/angeo-40-379-2022, https://doi.org/10.5194/angeo-40-379-2022, 2022
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The radial diffusion mechanism is of utmost importance to both the acceleration and loss of relativistic electrons in the outer radiation belt and, consequently, for physics-based models, which provide nowcasting and forecasting of the electron population. In the framework of the "SafeSpace" project, we have created a database of calculated radial diffusion coefficients, and, furthermore, we have exploited it to provide insights for future modelling efforts.
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.
Christos Katsavrias, Constantinos Papadimitriou, Sigiava Aminalragia-Giamini, Ioannis A. Daglis, Ingmar Sandberg, and Piers Jiggens
Ann. Geophys., 39, 413–425, https://doi.org/10.5194/angeo-39-413-2021, https://doi.org/10.5194/angeo-39-413-2021, 2021
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The nature of the semi-annual variation in the relativistic electron fluxes in the Earth's outer radiation belt has been a debate for over 30 years. Our work shows that it is primarily driven by the Russell–McPherron effect, which indicates that reconnection is responsible not only for the short-scale but also the seasonal variability of the electron belt as well. Moreover, it is more pronounced during the descending phase of the solar cycles and coexists with periods of fast solar wind speed.
Rajkumar Hajra
Ann. Geophys., 39, 181–187, https://doi.org/10.5194/angeo-39-181-2021, https://doi.org/10.5194/angeo-39-181-2021, 2021
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Geomagnetic activity is known to exhibit semi-annual variation with larger occurrences during equinoxes. A similar seasonal feature was reported for relativistic (∼ MeV) electrons throughout the entire outer zone radiation belt. Present work, for the first time reveals that electron fluxes increase with an ∼ 6-month periodicity in a limited L-shell only with large dependence in solar activity cycle. In addition, flux enhancements are not essentially equinoctial.
Alexander S. Kovtyukh
Ann. Geophys., 39, 171–179, https://doi.org/10.5194/angeo-39-171-2021, https://doi.org/10.5194/angeo-39-171-2021, 2021
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This is a continuation of work published in Annales Gephysicae between 2016 and 2020. In this paper, a new method for analyzing experimental data is proposed, calculations are carried out, and a new class of distributions of particles of radiation belts is constructed. As a result of this work, new, finer physical regularities of the structure of the Earth's proton radiation belt and its solar-cyclic variations have been obtained, which cannot be obtained by other methods.
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.
Alla V. Suvorova, Alexei V. Dmitriev, and Vladimir A. Parkhomov
Ann. Geophys., 37, 1223–1241, https://doi.org/10.5194/angeo-37-1223-2019, https://doi.org/10.5194/angeo-37-1223-2019, 2019
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The Earth's radiation belts control the space environment, often affecting the GPS signal propagation and satellite operations. Intense fluxes of energetic particles can penetrate even below the inner belt near the Equator. We analysed electron penetrations under geomagnetic quiet conditions and found in the solar wind an external driver cause. Satellite observations prove that disturbance of the inner belt was associated with impact of plasma jets formed in the solar wind nearby the Earth.
Angélica Sicard, Daniel Boscher, Sébastien Bourdarie, Didier Lazaro, Denis Standarovski, and Robert Ecoffet
Ann. Geophys., 36, 953–967, https://doi.org/10.5194/angeo-36-953-2018, https://doi.org/10.5194/angeo-36-953-2018, 2018
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GREEN (Global Radiation Earth ENvironment) is a new model providing particle fluxes at any location in the radiation belts, for energy between 1 keV
and 10 MeV for electrons and between 1 keV and 800 MeV for protons. This model is composed of global models (AE8 and AP8, and SPM) and
local models (SLOT model, OZONE and IGE-2006 for electrons; OPAL and IGP for protons).
Run Shi, Wen Li, Qianli Ma, Seth G. Claudepierre, Craig A. Kletzing, William S. Kurth, George B. Hospodarsky, Harlan E. Spence, Geoff D. Reeves, Joseph F. Fennell, J. Bernard Blake, Scott A. Thaller, and John R. Wygant
Ann. Geophys., 36, 781–791, https://doi.org/10.5194/angeo-36-781-2018, https://doi.org/10.5194/angeo-36-781-2018, 2018
Cited articles
Agapitov, O., Artemyev, A., Krasnoselskikh, V., Khotyaintsev, Y. V., Mourenas,
D., Breuillard, H., Balikhin, M., and Rolland, G.: Statistics of whistler
mode waves in the outer radiation belt: Cluster STAFF-SA measurements,
J. Geophys. Res.-Space, 118, 3407–3420,
https://doi.org/10.1002/jgra.50312,
2013. a
Asikainen, T.: Calibrated and corrected POES/MEPED energetic particle
observations, in: The ESPAS e-infrastructure: Access to data in near-Earth
space, edited by: Belehaki, A., Hapgood, M., and Watermann, J., EDP Sciences,
57–69, EDP Open, London, UK, https://doi.org/10.1051/978-2-7598-1949-2, 2017. a
Asikainen, T.: New Homogeneous Composite Of Energetic Electron Fluxes From
POES: 2. Intercalibration of SEM-1 and SEM-2, J. Geophys.
Res.-Space, 124, 5761–5782, https://doi.org/10.1029/2019JA026699,
2019. a
Asikainen, T. and Mursula, K.: Recalibration of NOAA/MEPED energetic proton
measurements, J. Atmos. Sol.-Terr. Phy., 73, 335–347,
https://doi.org/10.1016/j.jastp.2009.12.011, 2011. a
Asikainen, T. and Mursula, K.: Correcting the NOAA/MEPED energetic electron
fluxes for detector efficiency and proton contamination, J. Geophys. Res.,
118, 6500–6510, https://doi.org/10.1002/jgra.50584, 2013. a, b
Asikainen, T., Mursula, K., and Maliniemi, V.: Correction of detector noise
and recalibration of NOAA/MEPED energetic proton fluxes, J. Geophys. Res.,
117, A09204, https://doi.org/10.1029/2012JA017593, 2012. a
Baker, D., Kanekal, S., Hoxie, V., Batiste, S., Bolton, M., Li, X., Elkington,
S., Monk, S., Reukauf, R., Steg, S., Westfall, J., Belting, C., Bolton, B.,
Braun, D., Cervelli, B., Hubbell, K., Kien, M., Knappmiller, S., Wade, S.,
and Friedel, R.: The Relativistic Electron-Proton Telescope (REPT) Instrument
on Board the Radiation Belt Storm Probes (RBSP) Spacecraft: Characterization
of Earth's Radiation Belt High-Energy Particle Populations, Space Sci.
Rev., 179, 337–381, https://doi.org/10.1007/s11214-012-9950-9, 2012. a
Baker, D. N., Erickson, P. J., Fennell, J. F., Foster, J. C., Jaynes,
A. N., and Verronen, P. T.: Space Weather Effects in the Earth's Radiation
Belts, Space Sci. Rev., 214, 17, https://doi.org/10.1007/s11214-017-0452-7, 2018. a, b
Bingham, S. T., Mouikis, C. G., Kistler, L. M., Paulson, K. W., Farrugia,
C. J., Huang, C. L., Spence, H. E., Reeves, G. D., and Kletzing, C.: The
Storm Time Development of Source Electrons and Chorus Wave Activity During
CME- and CIR-Driven Storms, J. Geophys. Res.-Space,
124, 6438–6452, https://doi.org/10.1029/2019JA026689,
2019. a, b, c, d, e, f
Blake, J., Carranza, P., Claudepierre, S., Clemmons, J., Jr, W., Dotan, Y.,
Fennell, J., Fuentes, F., Galvan, R., George, J., Henderson, M., Lalic, M.,
Lin, A., Looper, M., Mabry, D., Mazur, J., Mccarthy, B., Nguyen, C.,
O'Brien, T., and Zakrzewski, M.: The Magnetic Electron Ion Spectrometer
(MagEIS) instruments aboard the Radiation Belt Storm Probe (RBSP) spacecraft,
Space Sci. Rev., 179, 383–421, https://doi.org/10.1007/s11214-013-9991-8, 2013. a
Blum, L. W., Artemyev, A., Agapitov, O., Mourenas, D., Boardsen, S.,
and Schiller, Q.: EMIC Wave-Driven Bounce Resonance Scattering of
Energetic Electrons in the Inner Magnetosphere, J. Geophys.
Res.-Space, 124, 2484–2496, https://doi.org/10.1029/2018JA026427, 2019. a
Bortnik, J., Thorne, R. M., O'Brien, T. P., Green, J. C., Strangeway, R. J.,
Shprits, Y. Y., and Baker, D. N.: Observation of two distinct, rapid loss
mechanisms during the 20 November 2003 radiation belt dropout event, J. Geophys. Res.-Space, 111, A12216, https://doi.org/10.1029/2006JA011802,
2006. a, b
Bothmer, V. and Schwenn, R.: The structure and origin of magnetic clouds in the solar wind, Ann. Geophys., 16, 1–24, https://doi.org/10.1007/s00585-997-0001-x, 1998. a
Bounds, S.: Data Index, available at: https://emfisis.physics.uiowa.edu/data/index, last access: 27 August 2020. a
Boyd, A. J., Spence, H. E., Huang, C.-L., Reeves, G. D., Baker, D. N., Turner,
D. L., Claudepierre, S. G., Fennell, J. F., Blake, J. B., and Shprits, Y. Y.:
Statistical properties of the radiation belt seed population, J.
Geophys. Res.-Space, 121, 7636–7646,
https://doi.org/10.1002/2016JA022652,
2016. a, b
Burlaga, L., Sittler, E., Mariani, F., and Schwenn, R.: Magnetic loop
behind an interplanetary shock: Voyager, Helios, and IMP 8 observations, J.
Geophys. Res., 86, 6673–6684, https://doi.org/10.1029/JA086iA08p06673, 1981. a
Burtis, W. J. and Helliwell, R. A.: Banded chorus – A new type
of VLF radiation observed in the magnetosphere by OGO 1 and OGO 3, J.
Geophys. Res., 74, 3002, https://doi.org/10.1029/JA074i011p03002, 1969. a
Cattell, C. A., Breneman, A. W., Thaller, S. A., Wygant, J. R.,
Kletzing, C. A., and Kurth, W. S.: Van Allen Probes observations of
unusually low frequency whistler mode waves observed in association with
moderate magnetic storms: Statistical study, Geophys. Res. Lett., 42,
7273–7281, https://doi.org/10.1002/2015GL065565, 2015. a
Clilverd, M. A., Rodger, C. J., and Ulich, T.: The importance of atmospheric
precipitation in storm-time relativistic electron flux drop outs, Geophys.
Res. Lett., 33, L01102, https://doi.org/10.1029/2005GL024661,
2006. a
Clilverd, M. A., Rodger, C. J., Millan, R. M., Sample, J. G., Kokorowski, M.,
McCarthy, M. P., Ulich, T., Raita, T., Kavanagh, A. J., and Spanswick, E.:
Energetic particle precipitation into the middle atmosphere triggered by a
coronal mass ejection, J. Geophys. Res.-Space, 112, A12206,
https://doi.org/10.1029/2007JA012395,
2007. a, b
Douma, E., Rodger, C., Blum, L., and Clilverd, M.: Occurrence characteristics
of relativistic electron microbursts from SAMPEX observations: Occurrence of
relativistic microbursts, J. Geophys. Res.-Space,
122, 8096–8107, https://doi.org/10.1002/2017JA024067, 2017. a
Fenrich, F. R. and Luhmann, J. G.: Geomagnetic response to magnetic clouds
of different polarity, Geophys. Res. Lett., 25, 2999–3002,
https://doi.org/10.1029/98GL51180, 1998. a
Gokani, S. A., Kosch, M., Clilverd, M., Rodger, C. J., and Sinha, A. K.: What
Fraction of the Outer Radiation Belt Relativistic Electron Flux at L = 3–4.5
Was Lost to the Atmosphere During the Dropout Event of the St. Patrick's Day
Storm of 2015?, J. Geophys. Res.-Space, 124,
9537–9551, https://doi.org/10.1029/2018JA026278,
2019. a, b
Grandin, M., Kero, A., Partamies, N., McKay, D., Whiter, D.,
Kozlovsky, A., and Miyoshi, Y.: Observation of pulsating aurora
signatures in cosmic noise absorption data, Geophys. Res. Lett., 44,
5292–5300, https://doi.org/10.1002/2017GL073901, 2017. a
Hargreaves, J. K., Birch, M. J., and Evans, D. S.: On the fine structure of medium energy electron fluxes in the auroral zone and related effects in the ionospheric D-region, Ann. Geophys., 28, 1107–1120, https://doi.org/10.5194/angeo-28-1107-2010, 2010. a
Hartley, D. P., Kletzing, C. A., Santolík, O., Chen, L., and
Horne, R. B.: Statistical Properties of Plasmaspheric Hiss From Van Allen
Probes Observations, J. Geophys. Res.-Space, 123,
2605–2619, https://doi.org/10.1002/2017JA024593, 2018. a
Hendry, A., Rodger, C., and Clilverd, M.: Evidence of sub-MeV EMIC-driven
electron precipitation: SUB-MEV EMIC PRECIPITATION, Geophys. Res.
Lett., 44, 1210–1218, https://doi.org/10.1002/2016GL071807, 2017. a
Huttunen, K. E. J., Schwenn, R., Bothmer, V., and Koskinen, H. E. J.: Properties and geoeffectiveness of magnetic clouds in the rising, maximum and early declining phases of solar cycle 23, Ann. Geophys., 23, 625–641, https://doi.org/10.5194/angeo-23-625-2005, 2005. a
Jaynes, A. N., Baker, D. N., Singer, H. J., Rodriguez, J. V., Loto'aniu, T. M.,
Ali, A. F., Elkington, S. R., Li, X., Kanekal, S. G., Claudepierre, S. G.,
Fennell, J. F., Li, W., Thorne, R. M., Kletzing, C. A., Spence, H. E., and
Reeves, G. D.: Source and seed populations for relativistic electrons: Their
roles in radiation belt changes, J. Geophys. Res.-Space, 120, 7240–7254, https://doi.org/10.1002/2015JA021234,
2015. a, b, c, d
Jaynes, A. N., Ali, A. F., Elkington, S. R., Malaspina, D. M., Baker,
D. N., Li, X., Kanekal, S. G., Henderson, M. G., Kletzing, C. A., and
Wygant, J. R.: Fast Diffusion of Ultrarelativistic Electrons in the Outer
Radiation Belt: 17 March 2015 Storm Event, Geophys. Res. Lett., 45,
10874–10882, https://doi.org/10.1029/2018GL079786, 2018. a, b, c
Kalliokoski, M. M. H., Kilpua, E. K. J., Osmane, A., Turner, D. L., Jaynes, A. N., Turc, L., George, H., and Palmroth, M.: Outer radiation belt and inner magnetospheric response to sheath regions of coronal mass ejections: a statistical analysis, Ann. Geophys., 38, 683–701, https://doi.org/10.5194/angeo-38-683-2020, 2020. a
Kanekal, S. G., Baker, D. N., Blake, J. B., Klecker, B., Mewaldt,
R. A., and Mason, G. M.: Magnetospheric response to magnetic cloud
(coronal mass ejection) events: Relativistic electron observations from
SAMPEX and Polar, J. Geophys. Res., 104, 24885–24894,
https://doi.org/10.1029/1999JA900239, 1999. a
Kavanagh, A. J., Cobbett, N., and Kirsch, P.: Radiation Belt Slot Region
Filling Events: Sustained Energetic Precipitation Into the Mesosphere,
J. Geophys. Res.-Space, 123, 7999–8020,
https://doi.org/10.1029/2018JA025890, 2018. a
Kilpua, E., Koskinen, H. E. J., and Pulkkinen, T. I.: Coronal mass
ejections and their sheath regions in interplanetary space, Living Rev.
Sol. Phys., 14, 5, https://doi.org/10.1007/s41116-017-0009-6, 2017. a
Kilpua, E. K. J., Li, Y., Luhmann, J. G., Jian, L. K., and Russell, C. T.: On the relationship between magnetic cloud field polarity and geoeffectiveness, Ann. Geophys., 30, 1037–1050, https://doi.org/10.5194/angeo-30-1037-2012, 2012. a
Kilpua, E. K. J., Hietala, H., Turner, D. L., Koskinen, H. E. J.,
Pulkkinen, T. I., Rodriguez, J. V., Reeves, G. D., Claudepierre,
S. G., and Spence, H. E.: Unraveling the drivers of the storm time
radiation belt response, Geophys. Res. Lett., 42, 3076–3084,
https://doi.org/10.1002/2015GL063542, 2015a. a
Kilpua, E. K. J., Lumme, E., Andreeova, K., Isavnin, A., and
Koskinen, H. E. J.: Properties and drivers of fast interplanetary shocks
near the orbit of the Earth (1995–2013), J. Geophys. Res.-Space, 120, 4112–4125, https://doi.org/10.1002/2015JA021138,
2015b. a
Kim, H.-J. and Chan, A. A.: Fully adiabatic changes in storm time
relativistic electron fluxes, J. Gepohys. Res., 102, 22107–22116,
https://doi.org/10.1029/97JA01814, 1997. a
Kletzing, C. A., Kurth, W. S., Acuna, M., MacDowall, R. J., Torbert,
R. B., Averkamp, T., Bodet, D., Bounds, S. R., Chutter, M.,
Connerney, J., Crawford, D., Dolan, J. S., Dvorsky, R.,
Hospodarsky, G. B., Howard, J., Jordanova, V., Johnson, R. A.,
Kirchner, D. L., Mokrzycki, B., Needell, G., Odom, J., Mark, D.,
Pfaff, R., Phillips, J. R., Piker, C. W., Remington, S. L.,
Rowland, D., Santolik, O., Schnurr, R., Sheppard, D., Smith, C. W.,
Thorne, R. M., and Tyler, J.: The Electric and Magnetic Field Instrument
Suite and Integrated Science (EMFISIS) on RBSP, Space Sci. Rev., 179,
127–181, https://doi.org/10.1007/s11214-013-9993-6, 2013. a
Koons, H. C. and Roeder, J. L.: A survey of equatorial magnetospheric wave
activity between 5 and 8 RE, Planet. Space Sci., 38, 1335–1341,
https://doi.org/10.1016/0032-0633(90)90136-E, 1990. a
Kovalick, T.: Public data from current and past space physics missions, available at: https://cdaweb.gsfc.nasa.gov/index.html/, last access: 25 August 2020. a
Korth, H., Thomsen, M. F., Borovsky, J. E., and McComas, D. J.: Plasma sheet
access to geosynchronous orbit, J. Geophys. Res.-Space, 104, 25047–25061, https://doi.org/10.1029/1999JA900292,
1999. a, b
Lam, M. M., Horne, R. B., Meredith, N. P., Glauert, S. A.,
Moffat-Griffin, T., and Green, J. C.: Origin of energetic electron
precipitation >30 keV into the atmosphere, J. Geophys. Res.-Space, 115, A00F08, https://doi.org/10.1029/2009JA014619, 2010. a, b
Li, H., Yuan, Z., Yu, X., Huang, S., Wang, D., Wang, Z., Qiao,
Z., and Wygant, J. R.: The enhancement of cosmic radio noise absorption
due to hiss-driven energetic electron precipitation during substorms,
J. Geophys. Res.-Space, 120, 5393–5407,
https://doi.org/10.1002/2015JA021113, 2015. a
Li, W., Thorne, R. M., Angelopoulos, V., Bortnik, J., Cully, C. M., Ni, B.,
LeContel, O., Roux, A., Auster, U., and Magnes, W.: Global distribution of
whistler-mode chorus waves observed on the THEMIS spacecraft, Geophys.
Res. Lett., 36, L09104, https://doi.org/10.1029/2009GL037595,
2009. a
Li, X., Baker, D. N., Temerin, M., Cayton, T. E., Reeves, E. G. D.,
Christensen, R. A., Blake, J. B., Looper, M. D., Nakamura, R., and
Kanekal, S. G.: Multisatellite observations of the outer zone electron
variation during the November 3–4, 1993, magnetic storm, J. Geophys. Res.,
102, 14123–14140, https://doi.org/10.1029/97JA01101, 1997. a, b
Ma, Q., Li, W., Bortnik, J., Thorne, R. M., Chu, X., Ozeke, L. G.,
Reeves, G. D., Kletzing, C. A., Kurth, W. S., Hospodarsky, G. B.,
Engebretson, M. J., Spence, H. E., Baker, D. N., Blake, J. B.,
Fennell, J. F., and Claudepierre, S. G.: Quantitative Evaluation of
Radial Diffusion and Local Acceleration Processes During GEM Challenge
Events, J. Geophys. Res.-Space, 123, 1938–1952,
https://doi.org/10.1002/2017JA025114, 2018. a
Maliniemi, V., Asikainen, T., Mursula, K., and Seppälä, A.:
QBO-dependent relation between electron precipitation and wintertime surface
temperature, J. Geophys. Res., 118, 6302–6310, https://doi.org/10.1002/jgrd.50518, 2013. a
Mann, I. R., Lee, E. A., Claudepierre, S. G., Fennell, J. F.,
Degeling, A., Rae, I. J., Baker, D. N., Reeves, G. D., Spence,
H. E., Ozeke, L. G., Rankin, R., Milling, D. K., Kale, A., Friedel,
R. H. W., and Honary, F.: Discovery of the action of a geophysical
synchrotron in the Earth's Van Allen radiation belts, Nat.
Commun., 4, 2795, https://doi.org/10.1038/ncomms3795, 2013. a
Mann, I. R., Ozeke, L. G., Murphy, K. R., Claudepierre, S. G.,
Turner, D. L., Baker, D. N., Rae, I. J., Kale, A., Milling, D. K.,
Boyd, A. J., Spence, H. E., Reeves, G. D., Singer, H. J.,
Dimitrakoudis, S., Daglis, I. A., and Honary, F.: Explaining the
dynamics of the ultra-relativistic third Van Allen radiation belt, Nat.
Phys., 12, 978–983, https://doi.org/10.1038/nphys3799, 2016. a
Mathie, R. A. and Mann, I. R.: On the solar wind control of Pc5 ULF
pulsation power at mid-latitudes: Implications for MeV electron acceleration
in the outer radiation belt, J. Geophys. Res., 106, 29783–29796,
https://doi.org/10.1029/2001JA000002, 2001. a
Meredith, N. P., Thorne, R. M., Horne, R. B., Summers, D., Fraser,
B. J., and Anderson, R. R.: Statistical analysis of relativistic electron
energies for cyclotron resonance with EMIC waves observed on CRRES, J. Geophys. Res.-Space, 108, 1250,
https://doi.org/10.1029/2002JA009700, 2003. a
Meredith, N. P., Horne, R. B., Glauert, S. A., Thorne, R. M.,
Summers, D., Albert, J. M., and Anderson, R. R.: Energetic outer zone
electron loss timescales during low geomagnetic activity, J. Geophys. Res.-Space, 111, A05212,
https://doi.org/10.1029/2005JA011516, 2006. a
Meredith, N. P., Horne, R. B., Sicard-Piet, A., Boscher, D., Yearby, K. H., Li,
W., and Thorne, R. M.: Global model of lower band and upper band chorus from
multiple satellite observations, J. Geophys. Res.-Space, 117, A10225, https://doi.org/10.1029/2012JA017978,
2012. a, b, c, d
NOAA: GOES Space Environment Monitor, available at: https://www.ngdc.noaa.gov/stp/satellite/goes/index.html, last access: 25 August 2020. a
O'Brien, T. P. and Moldwin, M. B.: Empirical plasmapause models from magnetic
indices, Geophys. Res. Lett., 30, 1152, https://doi.org/10.1029/2002GL016007,
2003. a
Osmane, A., Wilson III, L. B., Blum, L., and Pulkkinen, T. I.: On the
Connection between Microbursts and Nonlinear Electronic Structures in
Planetary Radiation Belts, Astrophys. J., 816, 51,
https://doi.org/10.3847/0004-637X/816/2/51, 2016. a
Partamies, N., Whiter, D., Kadokura, A., Kauristie, K., Nesse
Tyssøy, H., Massetti, S., Stauning, P., and Raita, T.: Occurrence
and average behavior of pulsating aurora, J. Geophys. Res.-Space, 122, 5606–5618, https://doi.org/10.1002/2017JA024039, 2017. a
Rae, I. J., Murphy, K. R., Watt, C. E. J., Sand hu, J. K., Georgiou,
M., Degeling, A. W., Forsyth, C., Bentley, S. N., Staples, F. A., and
Shi, Q.: How Do Ultra-Low Frequency Waves Access the Inner Magnetosphere
During Geomagnetic Storms?, Geophys. Res. Lett., 46, 10699–10709,
https://doi.org/10.1029/2019GL082395, 2019. a
Reeves, G.: Index of /data_pub, available at: https://www.rbsp-ect.lanl.gov/data_pub, last access: 25 August 2020. a
Reeves, G. D., McAdams, K. L., Friedel, R. H. W., and O'Brien, T. P.:
Acceleration and loss of relativistic electrons during geomagnetic storms,
Geophys. Res. Lett., 30, 1529, https://doi.org/10.1029/2002GL016513, 2003. a
Reeves, G. D., Spence, H. E., Henderson, M. G., Morley, S. K., Friedel, R.
H. W., Funsten, H. O., Baker, D. N., Kanekal, S. G., Blake, J. B., Fennell,
J. F., Claudepierre, S. G., Thorne, R. M., Turner, D. L., Kletzing, C. A.,
Kurth, W. S., Larsen, B. A., and Niehof, J. T.: Electron Acceleration in the
Heart of the Van Allen Radiation Belts, Science, 341, 991–994,
https://doi.org/10.1126/science.1237743, 2013. a
Richardson, I. G. and Cane, H. V.: Near-Earth Interplanetary Coronal
Mass Ejections During Solar Cycle 23 (1996–2009): Catalog and Summary of
Properties, Solar Phys., 264, 189–237, https://doi.org/10.1007/s11207-010-9568-6,
2010. a
Richardson, I. and Cane, H.: Near-Earth Interplanetary Coronal Mass Ejections Since January 1996, available at: http://www.srl.caltech.edu/ACE/ASC/DATA/level3/icmetable2.htm, last access: 25 August 2020. a
Rodger, C. J., Clilverd, M. A., Thomson, N. R., Gamble, R. J., Seppälä, A.,
Turunen, E., Meredith, N. P., Parrot, M., Sauvaud, J.-A., and Berthelier,
J.-J.: Radiation belt electron precipitation into the atmosphere: Recovery
from a geomagnetic storm, J. Geophys. Res.-Space,
112, A11307, https://doi.org/10.1029/2007JA012383,
2007. a
Rodger, C. J., Carson, B. R., Cummer, S. A., Gamble, R. J., Clilverd, M. A.,
Green, J. C., Sauvaud, J.-A., Parrot, M., and Berthelier, J.-J.: Contrasting
the efficiency of radiation belt losses caused by ducted and nonducted
whistler-mode waves from ground-based transmitters, J. Geophys.
Res.-Space, 115, A12208, https://doi.org/10.1029/2010JA015880,
2010a. a, b
Rodger, C. J., Clilverd, M. A., Green, J. C., and Lam, M. M.: Use of POES SEM-2
observations to examine radiation belt dynamics and energetic electron
precipitation into the atmosphere, J. Geophys. Res.-Space, 115, A04202, https://doi.org/10.1029/2008JA014023,
2010b. a, b
Rodger, C. J., Clilverd, M. A., SeppäLä, A., Thomson, N. R.,
Gamble, R. J., Parrot, M., Sauvaud, J.-A., and Ulich, T.: Radiation
belt electron precipitation due to geomagnetic storms: Significance to middle
atmosphere ozone chemistry, J. Geophys. Res.-Space,
115, A11320, https://doi.org/10.1029/2010JA015599, 2010. a
Rodger, C. J., Kavanagh, A. J., Clilverd, M. A., and Marple, S. R.: Comparison
between POES energetic electron precipitation observations and riometer
absorptions: Implications for determining true precipitation fluxes, J. Geophys. Res.-Space, 118, 7810–7821,
https://doi.org/10.1002/2013JA019439,
2013. a, b
Rodger, C. J., Cresswell-Moorcock, K., and Clilverd, M. A.: Nature's Grand
Experiment: Linkage between magnetospheric convection and the radiation
belts, J. Geophys. Res.-Space, 121, 171–189,
https://doi.org/10.1002/2015JA021537,
2016. a
Rodger, C. J., Turner, D. L., Clilverd, M. A., and Hendry, A. T.: Magnetic
Local Time-Resolved Examination of Radiation Belt Dynamics during High-Speed
Solar Wind Speed-Triggered Substorm Clusters, Geophys. Res. Lett.,
46, 10219–10229, https://doi.org/10.1029/2019GL083712,
2019. a
Salminen, A., Asikainen, T., Maliniemi, V., and Mursula, K.: Effect of
Energetic Electron Precipitation on the Northern Polar Vortex: Explaining the
QBO Modulation via Control of Meridional Circulation, J. Geophys.
Res.-Atmos., 124, 5807–5821, https://doi.org/10.1029/2018JD029296,
2019. a
Selesnick, R. S., Blake, J. B., and Mewaldt, R. A.: Atmospheric losses
of radiation belt electrons, J. Geophys. Res.-Space, 108, 1468, https://doi.org/10.1029/2003JA010160, 2003. a
Seppälä, A., Matthes, K., Randall, C. E., and Mironova, I. A.:
What is the solar influence on climate? Overview of activities during
CAWSES-II, Progress in Earth and Planetary Science, 1, 24,
https://doi.org/10.1186/s40645-014-0024-3, 2014. 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, b, c
Singer, H., Matheson, L., Grubb, R., Newman, A., and Bouwer, D.:
Monitoring space weather with the GOES magnetometers, in: GOES-8 and
Beyond, edited by: Washwell, E. R., Vol. 2812 of Society of
Photo-Optical Instrumentation Engineers (SPIE) Conference Series, Denver, CO, United States,
299–308, https://doi.org/10.1117/12.254077, 1996. a
Sivadas, N., Semeter, J., Nishimura, Y., and Kero, A.: Simultaneous
Measurements of Substorm-Related Electron Energization in the Ionosphere and
the Plasma Sheet, J. Geophys. Res.-Space, 122, 10528–10547,
https://doi.org/10.1002/2017ja023995, 2017. a
Summers, D., Ni, B., Meredith, N. P., Horne, R. B., Thorne, R. M.,
Moldwin, M. B., and Anderson, R. R.: Electron scattering by
whistler-mode ELF hiss in plasmaspheric plumes, J. Geophys. Res.-Space, 113, A04219, https://doi.org/10.1029/2007JA012678, 2008. a
Toh, H.: Final Dst index, available at: http://wdc.kugi.kyoto-u.ac.jp/dst_final/index.html, last access: 25 August 2020. a
Tsyganenko, N. A. and Sitnov, M. I.: Modeling the dynamics of the inner
magnetosphere during strong geomagnetic storms, J. Geophys. Res.-Space, 110, A03208, https://doi.org/10.1029/2004JA010798, 2005. a
Tu, W. and Li, X.: Adiabatic effects on radiation belt electrons at low
altitude, J. Geophys. Res.-Space, 116, A09201,
https://doi.org/10.1029/2011JA016468,
2011. a
Turner, D. L., Angelopoulos, V., Li, W., Hartinger, M. D., Usanova,
M., Mann, I. R., Bortnik, J., and Shprits, Y.: On the storm-time
evolution of relativistic electron phase space density in Earth's outer
radiation belt, J. Geophys. Res.-Space, 118,
2196–2212, https://doi.org/10.1002/jgra.50151, 2013. a
Turner, D. L., Angelopoulos, V., Morley, S. K., Henderson, M. G., Reeves,
G. D., Li, W., Baker, D. N., Huang, C.-L., Boyd, A., Spence, H. E.,
Claudepierre, S. G., Blake, J. B., and Rodriguez, J. V.: On the cause and
extent of outer radiation belt losses during the 30 September 2012 dropout
event, J. Geophys. Res.-Space, 119, 1530–1540,
https://doi.org/10.1002/2013JA019446,
2014. a, b, c
Turner, D. L., Kilpua, E. K. J., Hietala, H., Claudepierre, S. G.,
O'Brien, T. P., Fennell, J. F., Blake, J. B., Jaynes, A. N.,
Kanekal, S., Baker, D. N., Spence, H. E., Ripoll, J.-F., and
Reeves, G. D.: The Response of Earth's Electron Radiation Belts to
Geomagnetic Storms: Statistics From the Van Allen Probes Era Including
Effects From Different Storm Drivers, J. Geophys. Res.-Space, 124, 1013–1034, https://doi.org/10.1029/2018JA026066, 2019.
a, b, c
Tyssoy, H. N., Haderlein, A., Sandanger, M. I., and Stadsnes, J.:
Intercomparison of the POES/MEPED Loss Cone Electron Fluxes With the CMIP6
Parametrization, J. Geophys. Res.-Space, 124,
628–642, https://doi.org/10.1029/2018JA025745, 2019. a
Usanova, M. E., Drozdov, A., Orlova, K., Mann, I. R., Shprits, Y.,
Robertson, M. T., Turner, D. L., Milling, D. K., Kale, A., Baker,
D. N., Thaller, S. A., Reeves, G. D., Spence, H. E., Kletzing, C.,
and Wygant, J.: Effect of EMIC waves on relativistic and ultrarelativistic
electron populations: Ground-based and Van Allen Probes observations,
Geophys. Res. Lett., 41, 1375–1381, https://doi.org/10.1002/2013GL059024, 2014. a
Van Allen, J. A.: Observations of high intensity radiation by satellites
1958 Alpha and 1958 Gamma, in: Space Science Comes of Age: Perspectives in
the History of the Space Sciences, edited by: Hanle, P. A., Chamberlain,
V. D., and Brush, S. G., National Air and Space Museum, Smithsonian Institution, Smithsonian Institution Press, 1981, 58–73, 1981. a
Verronen, P. T., Rodger, C. J., Clilverd, M. A., and Wang, S.: First
evidence of mesospheric hydroxyl response to electron precipitation from the
radiation belts, J. Geophys. Res.-Atmos., 116, D07307,
https://doi.org/10.1029/2010JD014965, 2011. a
Xiao, F., Liu, S., Tao, X., Su, Z., Zhou, Q., Yang, C., He, Z.,
He, Y., Gao, Z., Baker, D. N., Spence, H. E., Reeves, G. D.,
Funsten, H. O., and Blake, J. B.: Generation of extremely low frequency
chorus in Van Allen radiation belts, J. Geophys. Res.-Space, 122, 3201–3211, https://doi.org/10.1002/2016JA023561, 2017. a
Yuan, Z., Li, M., Xiong, Y., Li, H., Zhou, M., Wang, D., Huang, S., Deng, X.,
and Wang, J.: Simultaneous observations of precipitating radiation belt
electrons and ring current ions associated with the plasmaspheric plume,
J. Geophys. Res.-Space, 118, 4391–4399,
https://doi.org/10.1002/jgra.50432,
2013. a
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.
We compared trapped outer radiation belt electron fluxes to high-latitude precipitating electron...
