Conveners
SWR3 – Inner Magnetospheric Dynamics and Coupling Processes: orals - part 1
- Alexander Lozinski (UCLA)
- Ravindra Desai (University of Warwick)
- Sarah Glauert (British Antarctic Survey)
SWR3 – Inner Magnetospheric Dynamics and Coupling Processes: Orals - part 2
- Ravindra Desai (University of Warwick)
- Sarah Glauert (British Antarctic Survey)
- Alexander Lozinski (UCLA)
SWR3 – Inner Magnetospheric Dynamics and Coupling Processes: Orals - part 3
- Alexander Lozinski (UCLA)
- Sarah Glauert (British Antarctic Survey)
- Ravindra Desai (University of Warwick)
SWR3 – Inner Magnetospheric Dynamics and Coupling Processes: Orals - part 4
- Alexander Lozinski (UCLA)
- Ravindra Desai (University of Warwick)
- Sarah Glauert (British Antarctic Survey)
Description
The inner magnetosphere hosts a dynamic range of plasma populations including the relativistic radiation belts, the ring current and cold plasmaspheric ions. These populations are tightly coupled via a range of micro-, meso- and macro-scale processes, driving a complex interplay of acceleration, transport and loss. For example, chorus waves are generated by injected plasma sheet electrons and then accelerate 100’s keV electrons to relativistic energies to form the radiation belts, with this acceleration being most efficient in regions of low plasma density. In turn, precipitation of radiation belt particles into the atmosphere balances ionospheric outflows of cold plasma into the inner magnetosphere. Further research into these and other cross-scale couplings is essential to develop the capability to reliably forecast inner magnetospheric dynamics and associated space weather risks and impacts. This session calls for observational, modelling and theoretical studies related to the inner magnetospheres, as well as review papers and mission concepts as well as comparative studies with other magnetospheres. We invite observational contributions from current missions such as Arase, Themis, MMS and GPS, from ground-based facilities such as EISCAT, SuperDARN and VLF receivers, and from historical datasets such as from the Van Allen Probes, Cluster and climatological studies involving even earlier solar cycles. We invite numerical contributions spanning Fokker Planck simulations, kinetic simulations of wave-particle interactions, and of the global magnetosphere and its couplings to the ionosphere and solar wind, as well as novel machine learning approaches and solutions.
Inner magnetospheric dynamics and coupling processes are highly dynamic, in part due to the interaction of electrons with a variety of electromagnetic waves. Here we present a novel combination of observations made in Fennoscandia that reveal energetic electron precipitation into the D-region ionosphere due to these coupling processes. We identify various magnetospheric phenomena, including...
Particle precipitation is a significant energy input into the Earth’s ionosphere and plays an important role in magnetosphere-ionosphere coupling. Previous studies employed test particle simulations to investigate wave-particle interaction and associated precipitation, in which the wave evolution is presumed and the particle feedback to waves is neglected. In this study, we employ a...
In this study, we investigate the temporal responses of trapped relativistic electron fluxes in the heart of the outer radiation belt during three geomagnetic storm periods. We relate satellite observations of relativistic electron fluxes to the variations in electron precipitation made using VLF subionospheric propagation techniques, which are sensitive to D-region ionisation levels. Such...
Radial diffusion, driven by ultra-low frequency (ULF) waves, is a key process contributing to the acceleration and loss of electrons in the outer radiation belt by contributing to their inner or outer transport. Ground magnetometers give us continuous observations of such ULF waves but their usefulness is limited by the models used to transform ground measurements into their progenitor fields...
Electromagnetic ion cyclotron (EMIC) waves are generated in the equatorial regions of the inner magnetosphere. These waves propagate to the middle or low latitudes in the ionosphere through the ionospheric duct, detected as Pc1 waves by ground-based magnetometers. To figure out how the Pc1 wave power attenuates during propagation in space and on the ground, we investigated a magnetically...
Paulikas and Blake first approached the relationship between relativistic electron flux and solar wind speed in late 1979 and found a linear correlation when considering averages of solar wind speed and geosynchronous relativistic outer radiation belts electron flux for three different time intervals (1 day, 27 days, and 180 days). Many years later, Reeves et al., 2011 expanded the analyses...
Motivated by the need for improved radiation environment modeling, this study investigates the drivers behind sub-relativistic electron flux variations in the inner magnetosphere. We utilize electron flux measurements between 1 to 500 keV from the Hope and MagEIS instruments on board the RBSP satellites and the FEEPS instruments on board the MMS spacecraft. along with solar wind parameters and...
We investigate operational anomalies on GOES spacecraft that are attributed to shallow internal charging driven by enhanced flux of 100 - 300 keV electrons. This population is not traditionally associated with either surface charging (dominated by electrons with energies 10s of keV) or deep dielectric charging (typically linked to MeV-range electrons). Using data from 2017-2021 during the...
Fifty years after the Burton equation proposal for the coupling between solar wind and magnetosphere, as quantified by the Dst index, this work proposes a missing term for the injection of energy from the solar wind into the ring current. This term is associated with Alfvén waves and allows us to explain the linear trend observed in the recovery phase of Dst or SYM-H indices during the passage...
During 10-19 May 2024, the largest storm in the past 20 years took place, characterized with minimum Dst index of -412 nT. In the storm main phase, dropouts of >700 keV relativistic electrons are observed by Arase and NOAA 18 satellites throughout the outer radiation belts. During the storm recovery phase, the fluxes of relativistic electrons locally increase by about more than two orders of...
The radiation-belt electron flux exhibits dramatic variations across a range of spatial and temporal scales, including global‐scale radial transport, mesoscale injections, and local‐scale wave‐particle interactions. Long-term variability has been successfully captured by solving the Fokker Planck diffusion equation (e.g., BAS-RBM), incorporating radial, pitch-angle and energy diffusion and...
Understanding the dynamics of energetic electron populations in the Earth's outer radiation belt presents unique opportunities to grapple with the fundamental physics of relativistic charged particle trapping, loss, and acceleration in our own 'back-yard'.
On the one hand our understanding of radiation belt dynamics has evolved a great deal in the 60+ years since their discovery. However...
This study investigates chorus wave activity and relativistic electron dynamics in the radiation belts during the High-Speed Stream (HSS) event that occurred between October 12 and 16, 2016. Electron flux measurements from the REPT instrument and magnetic field data from EMFISIS aboard the Van Allen Probes were analyzed, along with solar wind and interplanetary magnetic field (IMF) parameters...
Chorus waves play a significant role in the dynamic evolution of energetic electrons in the inner magnetosphere. Thus, understanding the spatial and temporal dynamics of these electrons requires global distributions of chorus waves, which are not usually possible to obtain from a single satellite mission. In this study, we use 11 years of data from both the Van Allen Probes mission and the...
Whistler-mode waves are commonly observed in magnetized plasma environments, such as Earth’s inner magnetosphere, where wave-particle interactions play a significant role in radiation belt electron dynamics during geomagnetically active periods. Several mechanisms have been proposed for the generation of whistler-mode waves within the dense plasmasphere and plasmaspheric plumes, including...
We report an observation of long-lasting echo trains of lightning-generated whistlers recorded by the WBD instruments on the Cluster spacecraft near the plasmapause on 23 April 2002 during an interval of quasiperiodic emissions. The whistler traces exhibit spectral discontinuities, which split each of them into two branches around 3.6 kHz, with lower-frequency components being stronger and...
The Radiation Belt Forecasting Model and Framework (RBFMF) provides real-time forecasts and hindcasts of the radiation environment, which are used as inputs for the Satellite Charging Assessment Tool (Sat-CAT). Sat-Cat is used by satellite operators to model both long term and real-time effects of internal charging on satellite components. We will present the validation results of the RBFMF,...
Given the critical impact of accurate radiation belt modeling on space radiation environment restitution and forecasting, data assimilation has been employed to enhance physical models estimations since their earliest days. The method, allows the correction of the theoretical description of a given model, thanks to the ingestion of in-situ observations. Precisely, the widely adopted approach...
Quasilinear diffusion coefficients can be used to characterise the statistical response of charged particles to perturbations by plasma waves, via resonant wave-particle interactions. The calculation of these coefficients is sufficiently complicated and arduous to render it prohibitive to many potential users, because of the expense in time spent developing the code. We present and describe...
The Earth’s magnetosphere evolves dynamically under the influence of solar activity. The solar wind is a persistent stream of plasma carrying the interplanetary magnetic field and continuously interacts with the magnetosphere, governing its structure and behavior. Transient solar phenomena, such as Coronal Mass Ejections (CMEs) and High-Speed Solar Wind Streams (HSSs), further modulate this...
The physical mechanisms shaping the electron flux patterns in the inner boundary of the Earth’s outer radiation belt under the influence of different solar wind structures are well established in the literature. These processes are closely linked to the source and seed population injections, as well as wave-particle interactions that efficiently accelerate electrons crossing L-shells. The...
Energetic particle precipitation (EPP) into the atmosphere can influence the chemical composition from the upper stratosphere to the lower thermosphere. The impact of precipitated relativistic electrons from the radiation belt on atmospheric chemistry and dynamics remain unresolved. In this study, we use the VERB-4D code to simulate radiation belt electron dynamics during geomagnetic storms,...
The current state of the art in relativistic electron radiation belt models for operational needs come in two flavours – a “nowcast” based on data assimilation of relevant and timely measurements into a physics based model, and limited “forecasts'' based on statistical forecasts of indices or solar wind parameters that govern the dynamics in physical models. The FARBES (Forecast of Actionable...
Auroral Kilometric Radiation (AKR) is a strong Earth-based radio emission generated by the acceleration of electrons along auroral latitude magnetic field lines. AKR is closely linked to auroral ionospheric activity, with greater irradiance correlating with stronger auroral electrojets and enhanced particle precipitation. AKR provides a means to remotely sense ionosphere-magnetosphere...
High-speed streams (HSSs) and interplanetary coronal mass ejections (ICMEs) are two primary solar wind structures responsible for driving geomagnetic storms. These structures originate from distinct solar sources and differ in terms of plasma composition and dynamics. One important consequence of their interaction with the Earth's magnetosphere is the generation of plasma waves, including...
