Inter- and Transdisciplinary Sessions
Disciplinary sessions AS–GM
Disciplinary sessions GMPV–TS

Session programme


ST – Solar-Terrestrial Sciences

Programme group chair: Olga Malandraki

ST 2020 Hannes Alfvén Medal Lecture & 2021 Julius Bartels Medal Lecture & 2020 Division Outstanding ECS Award Lecture
Convener: Olga Malandraki
| Fri, 23 Apr, 15:00–17:00 (CEST)

Please feel free to access the presentation file.

Convener: Olga Malandraki
Fri, 23 Apr, 13:30–14:30 (CEST)
EGU 2020/2021 Jean Dominique Cassini Medal Lectures & PS/ST Arne Richter Award for Outstanding ECS Lectures
Conveners: Alberto Montanari, Helen Glaves
| Thu, 22 Apr, 11:00–15:00 (CEST)

ST1 – The Sun and Heliosphere

Programme group scientific officers: Manuela Temmer, Olga Malandraki


This session traditionally provides a forum for the discussion of all aspects of solar and heliospheric physics. Popular topics have included solar cycle dependencies of the Sun, solar wind and heliosphere, Coronal Mass Ejection research, studies of energetic particles throughout the heliosphere, and the outer boundaries of the heliosphere. We encourage contributions related to all ongoing and planned space missions, to ground-based experiments and to theoretical research. Papers presenting ideas for future space missions and experiments are very welcome in this session. The session will consist of both oral and poster presentations.

Convener: Manuela Temmer | Co-conveners: André Galli, Olga Malandraki
vPICO presentations
| Mon, 26 Apr, 11:00–12:30 (CEST), 13:30–15:00 (CEST)

The heliosphere is permeated with energetic particles of different compositions, energy spectra and origins. Two major populations of these particles are galactic cosmic rays (GCRs), which originate from outside of the heliosphere and are constantly detected at Earth, and solar energetic particles (SEPs) which are accelerated at/near the Sun during solar flares or by shock fronts associated with the transit of coronal mass ejections. Enhancements in energetic particle fluxes at Earth pose a hazard to humans and technology in space and at high altitudes. Within the magnetosphere, energetic particles are present in the radiation belts, and particle precipitation is responsible for the aurora and for hazards to satellites. Energetic particles have also been shown to cause changes is the chemistry of the middle and upper atmosphere, thermodynamic effects in the upper troposphere and lower stratosphere region, and can influence components of the global electric circuit. This session will aim to address the transport of energetic particles through the heliosphere, their detection at Earth and the effects they have on the terrestrial atmosphere when they arrive. It will bring together scientists from several fields of research in what is now very much an interdisciplinary area. The session will allow sharing of expertise amongst international researchers as well as showcase the recent advances being made in this field, which demonstrate the importance of the study of these energetic particle populations

Co-organized by AS4
Convener: Simon ThomasECSECS | Co-conveners: Nina Dresing, Graeme MarltonECSECS
vPICO presentations
| Mon, 26 Apr, 09:00–10:30 (CEST)

ESA/NASA's mission Solar Orbiter was launched in February 2020, and the in-situ instruments have started their science operations in June. The mission’s unique design will enable breakthrough science focusing on the linkage between the Sun and the heliosphere. By approaching as close as 0.28 AU from the Sun and orbiting the Sun in a plane up to 33 degrees heliographic latitude, Solar Orbiter will view the Sun and corona with remote imaging with high spatial resolution, and acquire in-situ measurements of the surrounding heliosphere. Solar Orbiter had its first perihelion near 0.51 AU in June 2020, its first Venus flyby in December and its second perihelion at 0.49 AU on 10 February 2021. Presentations covering instrument performance during commissioning and calibration, initial data and first scientific results from the first perihelia and the cruise phase (together with contextual ground and space-based observations), and theoretical predictions are solicited.

Convener: Yannis Zouganelis | Co-conveners: David Lario, Daniel Mueller, Teresa Nieves-Chinchilla
vPICO presentations
| Tue, 27 Apr, 11:00–15:00 (CEST)

The Sun’s corona is the birthplace of the solar wind, coronal mass ejections, associated shock waves and solar energetic particles which all are fundamental drivers of space weather. The key physical processes at the origin of these phenomena, i.e. the heating and acceleration of the coronal plasma and energetic particles, have not been clarified to date. During EGU 2021 Parker Solar Probe (PSP) will go through its eight´s perihelion of its 24 scheduled orbits around the Sun. During this perihelion the spacecraft will go as close to the Sun as 15.6 solar radii. PSP has already provided a treasure trove worth of in-situ and remote sensing data. The data from the previous orbits have revealed phenomena never seen before. Solar Orbiter (SO) was successfully launched on 10 February 2020. The in-situ instruments have become fully operational and the remote sensing instruments have also been switched on. Combining the PSP observations with data from SO, with remote sensing observations from SDO, STEREO and Proba2, with other in-situ data, e.g., from ACE and DSCOVR, with ground-based observations and with theoretical models is a challenging and exciting task. This session invites scientific contributions on all aspects of research addressed to the exploration of our near-Sun environment, with special focus on the new observations from PSP and SO and other complimenting observations and models.

Convener: Volker Bothmer | Co-conveners: Olga Malandraki, Nour E. Raouafi, Alexis Rouillard, Manuela Temmer
vPICO presentations
| Tue, 27 Apr, 15:30–17:00 (CEST)

The majority of space plasmas are in a turbulent state, displaying fluctuations and non-linear behaviour at a broad range of scales. As well as being of fundamental interest, this turbulence may have important effects, such as heating of the solar wind and corona, acceleration of energetic particles, and interaction with magnetic reconnection and shocks. Measurements also suggest the presence of plasma instabilities which may generate quasi-linear waves, such as, e.g., Alfven-Ion-Cyclotron waves at ion scales and whistler waves at electron scales. Many aspects of the turbulence and instabilities are not well understood, in particular, the energy injection mechanism to the cascade, the non-linear turbulent cascade and dissipation mechanisms, non-linear instability saturation mechanisms, and the interaction between instabilities and turbulence. This session will address these questions though discussion of observational, theoretical, numerical, and laboratory work to understand these processes. This session is relevant to many currently operating missions (e.g., Wind, Cluster, MMS, STEREO, THEMIS, Van Allen Probes, DSCOVR) and in particular for Solar Orbiter and Solar Probe Plus.

Convener: Olga Alexandrova | Co-conveners: Petr Hellinger, Luca Sorriso-Valvo, Julia StawarzECSECS, Daniel Verscharen
vPICO presentations
| Wed, 28 Apr, 11:00–14:15 (CEST)

Current sheets and 2D magnetic islands or 3D blobs, flux ropes, and plasmoids observed in the solar wind at various scales play a significant role in local particle acceleration to keV-MeV energies. The resulting energetic particle enhancements as well as plasma/magnetic field variations constitute a potentially hazardous condition in the interplanetary and near-Earth space. Current sheets are self-organized structures that are formed ubiquitously in cosmic and laboratory plasmas owing to a change in the magnetic field direction, at strong discontinuities, and as a result of turbulence. Not surprisingly, dynamic processes occurring at current sheets and in their vicinity have a striking similarity in different plasmas. Current sheets experience magnetic reconnection that in turn leads to many subsequent nonlinear effects, triggering the development of a turbulent cascade, the formation of magnetic islands/flux ropes/plasmoids/blobs, and local acceleration of charged particles. These processes are observed from the corona to the outer heliosphere and may often be described by the same equations. They also can be linked physically as some of the structures originating from the corona survive and evolve further in the solar wind. These processes have been studied by different scientific teams in independent ways, but currently there is a tendency to analyze them employing a unified approach.
This interdisciplinary session will bring together specialists from different plasma physics communities, bridging gaps in the understanding of the origin of coherent structures and the development of dynamical processes associated with current sheets. We invite researchers to share recent results of their theoretical studies, modelling and observations. Contributions that discuss and compare different mechanisms of local particle energization that occur in laboratory plasmas, the solar corona, magnetospheres of planets and the heliosphere are especially welcome.

Public information:

Dear colleagues,

Welcome to session ST1.6. "Dynamical processes and particle acceleration associated with current sheets, magnetic islands and turbulence-borne structures in space plasmas"!
Here you can find YouTube recordings of the full version of talks presented by ST1.6 speakers at the Zoom meeting on 29 April 2021 :

Session I: https://youtu.be/urFWlu2LjOE (Speakers: Timofey Sagitov, Valentina Zharkova, Sophie Musset, Philippa Browning, Patricio A. Munoz, Roman Kislov, and Alexander Khokhlachev)

Session II: https://youtu.be/09K4q5nVZuM (Speakers: Zdeněk Němeček, Helmi Malova, Olga Khabarova, Laxman Adhikari, Xiaozhou Zhao, Mitsuo Oka, Harald Kucharek, Rui Pinto, and Mikhail Fridman

The meeting program: https://drive.google.com/file/d/1y9H4iqOMjU6A35JGElajm7MHZv3lDgpu/view

Convener: Olga Khabarova | Co-conveners: Spiro Antiochos, Roman KislovECSECS, Jakobus le Roux, Olga Malandraki
vPICO presentations
| Wed, 28 Apr, 09:00–10:30 (CEST)

The “Theory and Simulation of Solar System Plasmas” session solicits presentations of the latest results from theoretical investigations and numerical simulations in space plasma-physics from microscopic to global scales, in comparison with experiments and observations in the heliosphere: at the Sun, in the solar corona, in interplanetary space and in planetary magnetospheres. There are challenging questions in fundamental solar system plasma physics which require the analyses of huge amounts of data, in particular of the particle kinetics. Machine learning techniques have to be used. We further encourage presentations of theory and simulation results relevant to current, forthcoming and proposed space missions. Each year a topic of special interest is chosen as a focus of the session. For 2021 this focus will be on synergies between observations in the solar wind made by Solar Orbiter and Parker Solar Probe with theory and simulation.

Convener: Giovanni Lapenta | Co-conveners: Philippa Browning, Jörg Büchner, Shangbin Yang
vPICO presentations
| Mon, 26 Apr, 11:00–12:30 (CEST), 13:30–15:00 (CEST)

The solar wind is an uninterrupted flow of highly ionised plasma that fills the heliosphere and is crossed by strong transient perturbations such as coronal mass ejections (CMEs) and (corotating) stream interaction regions (SIRs). These phenomena are capable of driving large disturbances at Earth as well as at the other planets. Remote-sensing observations from multiple vantage points, in-situ measurements from multiple well-separated locations, and novel modelling efforts have been employed systematically to study the properties of the solar wind plasma and of solar transients in general, from their formation to their arrival at different in-situ locations. However, despite the number of past and current spacecraft missions distributed throughout the heliosphere, it is still difficult to fully understand the properties of these phenomena, including their 3D structure (both global and local) and their evolution with heliocentric distance.

Studies of the ambient solar wind and its transient phenomena from their origin (the Sun) through their interplanetary journey are possible thanks to remote-sensing and in-situ observational data and models. From an observational perspective, for example, the recently launched Parker Solar Probe, BepiColombo, and Solar Orbiter have significantly increased the amount of available spacecraft in the inner heliosphere. From a modelling perspective, the recent years have seen an increase in both coronal and heliospheric models that operate in different regimes and dimensions. All these aspects will provide us with the perfect opportunity to test, validate, and refine the current knowledge of the solar wind and its transient phenomena and their interactions at different heliocentric distances. Accordingly, the aim of this session is to showcase the latest observational and modelling efforts regarding the origin and evolution of the solar wind, CMEs, and SIRs during their propagation throughout the heliosphere as seen from multiple vantage points, and to foresee future developments.

Convener: Erika PalmerioECSECS | Co-conveners: David BarnesECSECS, Rui Pinto
vPICO presentations
| Mon, 26 Apr, 15:30–17:00 (CEST)

Space, laboratory, and astrophysical plasmas are seemingly different environments, which however host very similar processes: among them, turbulence, magnetic reconnection, and shocks, which all result in particle acceleration. These processes are highly non-linear, and closely interlinked. On the one hand, the turbulence cascade favors the onset of magnetic reconnection between magnetic islands and, on the other hand, magnetic reconnection can trigger turbulence in the reconnection outflows and separatrices. Similarly, shocks may form in collisional and collisionless reconnection processes and can be responsible for turbulence formation, as for instance in the turbulent magnetosheath.

We are now in a fortunate time when the investigation of these processes based on simulations and observations are converging: simulations can deliver output which is approaching, in temporal and spatial scales, and in the coexistence of several scales, the complexity of an increasing number of the processes of interest. On the observation side, high cadence measurements of particles and fields, high resolution 3D measurements of particle distribution functions and multipoint measurements make it easier to reconstruct the 3D space surrounding the spacecrafts. The ever growing amount of data that both simulations and observations produce can be then combed through and organized with Artificial Intelligence and Machine Learning methods.

This session welcomes simulations, observational, and theoretical works relevant for the study of the above mentioned plasma processes. Particularly welcome this year will be works focusing on the common aspects of turbulence, reconnection, and shocks in space, laboratory, and astrophysical plasmas. We also encourage papers proposing new methods, especially those rooted in Artificial Intelligence and Machine Learning, to extract new knowledge from these big observational and simulated data sets.

Co-organized by ST1
Convener: Maria Elena Innocenti | Co-conveners: Jacob Bortnik, Jasper Halekas, Giovanni Lapenta, Francesco Pucci
vPICO presentations
| Tue, 27 Apr, 13:30–17:00 (CEST)

The session solicits contributions that report on nonthermal solar and planetary radio emissions. Coordinated multi-point observations from ground radio telescopes (e.g., LOFAR, LOIS, LWA1, URAN-2, UTR-2) and spacecraft plasma/wave experiments (e.g., Cassini, Cluster, Demeter, Galileo, Juno, Stereo, Ulysses and Wind) are especially encouraged. Presentations should focus on radiophysics techniques used and developed to investigate the remote magnetic field and the electron density in solar system regions, like the solar corona, the interplanetary medium and the magnetized auroral regions. Interest also extends to laboratory and experimental studies devoted to the comprehension of the generation mechanisms (e.g., cyclotron maser instability) and the acceleration processes (e.g., Alfven waves). Further preparations, evaluations, investigations, analyses of forthcoming space missions (like BepiColombo, Juice, Solar Orbiter, Solar Probe, SunRISE, Taranis) are also welcome.

Co-organized by ST1
Convener: Patrick Galopeau | Co-convener: Mohammed Y. Boudjada
vPICO presentations
| Tue, 27 Apr, 09:00–10:30 (CEST)
ITS4.2/PS4.4 EDI

The increasing amount of data from an increasing number of spacecraft in our solar system shouts out for new data analysis strategies. There is a need for frameworks that can rapidly and intelligently extract information from these data sets in a manner useful for scientific analysis. The community is starting to respond to this need. Machine learning, with all of its different facets, provides a viable playground for tackling a wide range of research questions. Algorithms to automatically detect and classify special features in time series data of the solar wind or in 2D images of planetary surfaces are examples of where machine learning approaches can support and improve existing models. Further, modern learning methods can encode properties of interest in lower dimensional space, and thus making them more searchable.

We encourage submissions dealing with machine learning approaches of all levels in planetary sciences and heliophysics. The aim of this session is to provide an overview of the current efforts to integrate machine learning technologies into data driven space research, to highlight state-of-the art developments and to generate a wider discussion on further possible applications of machine learning.

Co-organized by ESSI1/ST1
Convener: Mario D'Amore | Co-conveners: Ute Amerstorfer, Sahib JulkaECSECS, Angelo Pio Rossi
vPICO presentations
| Fri, 30 Apr, 09:00–10:30 (CEST)

ST2 – Magnetosphere

Programme group scientific officer: Yulia Bogdanova


This open session traditionally invites presentations on all aspects of the Earth’s magnetospheric physics, including the magnetosphere and its boundary layers, magnetosheath, bow shock and foreshock as well as solar wind-magnetosphere-ionosphere coupling. We welcome contributions on various aspects of magnetospheric observations, remote sensing of the magnetosphere’s processes, modelling and theoretical research. The presentations related to the current and planned space missions and to the value-added data services are also encouraged. This session is suitable for any contribution which does not fit more naturally into one of the specialised sessions and for contributions of wide community interest.

Convener: Yulia Bogdanova | Co-convener: C.-Philippe Escoubet
vPICO presentations
| Tue, 27 Apr, 09:00–10:30 (CEST)

The first part of the combined session is dedicated to the global magnetospheric dynamics. The state of the magnetosphere is controlled mainly by solar wind conditions. The interplanetary magnetic field (IMF) as well as solar wind plasma parameters regulate the energy input into the magnetosphere. While the IMF’s direction plays an important role in the coupling between the solar wind and magnetosphere, the questions remain on the effectiveness of the different plasma penetration mechanisms, their distribution at the magnetopause, and consequent global magnetospheric dynamics. Furthermore, the solar wind plasma parameters, such as density and velocity, may also change the magnetospheric state, but links between types of the solar wind structures and different magnetospheric modes need further investigation. The other open questions on the global magnetospheric dynamics include how the pre-conditioning of the magnetosphere changes its response to the solar wind impact and what are the roles of the ionosphere and ionosphere-magnetosphere coupling in the transition between magnetospheric modes. Global magnetospheric dynamics can be studied employing numerical simulations (MHD or kinetic), using empirical and semi-empirical models, and with the help of multipoint spacecraft observations. Besides, some past and future space missions can make global magnetospheric imaging providing information about positions and dynamics of the magnetospheric boundaries and global distribution of the ionospheric currents. We welcome any work presenting results on the global dynamics of the Earth’s magnetosphere as well as other planets’ magnetospheres.

The second part of the combined sessions is dedicated to the question how the Earth’s magnetosphere is affected by transient solar wind features. During the interaction between the solar wind transients and the Geospace system, important energy transfer and transport occur. Solar energy in various forms can propagate into the magnetosphere and ionosphere. In the meanwhile, charged particle energy can be transformed to electromagnetic energy, and vice versa. In-depth understanding of how the magnetosphere responds to transient solar wind features will enhance our knowledge on the solar wind-magnetosphere-ionosphere coupling. This special session will address the processes by which solar wind mass, momentum, and energy enter the magnetosphere. Regions of interest include the foreshock, bow shock, magnetosheath, magnetopause, cusps, the dayside magnetosphere, and the dayside ionosphere. This special session will provide a forum for the latest results from in-situ spacecraft observations, ground-based observations, and global simulations. Coordinated multi-point observations are especially encouraged. Planetary dayside Magnetospheric Interaction studies are also welcome.

Convener: C.-Philippe Escoubet | Co-conveners: Andrey Samsonov, Quanqi Shi, Yulia Bogdanova, Jie RenECSECS, David Sibeck, Hui Zhang, Qiugang Zong
vPICO presentations
| Tue, 27 Apr, 11:00–17:00 (CEST)

The first part of this combined session is dedicated to wave-particle interactions in the Earth's inner magnetosphere, radiation belt dynamics, and coupling. Wave-particle interactions represent a unique mechanism of an energy transfer in the nearly collisionless plasma environment of the Earth's inner magnetosphere. The resulting particle acceleration, transport, and loss, is crucial for understanding the dynamics of the Van Allen radiation belts. The forecasting of the radiation belts is further dependent on understanding the coupling with external regions (e.g. solar wind, foreshock, magnetosheath), and the processes that dictate their global dynamics. Additionally, precipitating magnetospheric particles cause changes in the ionospheric conductivity and may affect the upper atmospheric chemistry. The aim is to discuss the dynamics of the radiation belts, wave-particle interactions in the Earth's inner magnetosphere, as well as generation mechanisms and properties of involved electromagnetic emissions (EMIC, chorus, hiss, fast magnetosonic waves, etc.) in various frequency ranges. Theoretical and model contributions, as well as observational studies using data from older and recent satellite missions and ground-based instruments are encouraged.

The second part of the combined session is dedicated to the ionospheric sources of plasma and effects on the plasmasphere and magnetosphere. The Earth’s ionosphere is composed of cold plasma that includes protons and heavy ions. This plasma can escape to the magnetosphere following the Earth's magnetic field lines in the polar regions, and form the plasmasphere in the low- and mid-latitude regions. Therefore, the ionosphere is an important source that provides plasma to the magnetosphere and profoundly impacts its global dynamics. Depending on the path of these ions in the magnetosphere, they can end up forming cold and warm ionospheric outflows, plasmaspheric plumes, or the warm plasma cloak, and also feed the plasma sheet and ring current. Recent simulations and observations from numerous missions have sought to identify the origin, transport, and loss of plasma originating in the ionosphere and transported into the magnetosphere. These ions modify the plasma properties, and have an impact on key plasma dynamics such as wave generation and transport, particle acceleration or magnetic reconnection. This session welcomes presentations on all aspects related to ionospheric plasma in the magnetosphere.

Convener: Frantisek Nemec | Co-conveners: Sergio Toledo-RedondoECSECS, Richard Boynton, Fabien Darrouzet, Andrew Dimmock, Stephen Fuselier, Elena KronbergECSECS, Sarah VinesECSECS
vPICO presentations
| Fri, 30 Apr, 09:00–12:30 (CEST)

The Earth's inner magnetosphere contains different charged particle populations, such as the Van Allen radiation belts, ring current particles, and plasmaspheric particles. Their energy range varies from eV to several MeV, and the interplay among the charged particles provide feedback mechanisms which couple all those populations together. Ring current particles can generate various waves, for example, EMIC waves and chorus waves, which play important roles in the dynamic evolution of the radiation belts through wave-particle interactions. Ring current electrons can be accelerated to relativistic radiation belt electrons. Plasmaspheric medium can also affect these processes. In addition, precipitation of ring current and radiation belt particles will influence the ionosphere, while up-flows of ionospheric particles can affect dynamics in the inner magnetosphere. Understanding these coupling processes is crucial.

While the dynamics of outer planets’ magnetospheres are driven by a unique combination of internal coupling processes, these systems have a number of fascinating similarities which make comparative studies particularly interesting. We invite a broad range of theoretical, modelling, and observational studies focusing on the dynamics of the inner magnetosphere of the Earth and outer planets, including the coupling of the inner magnetosphere and ionosphere and coupling between the solar wind disturbances and various magnetospheric processes. Contributions from all relevant fields, including theoretical studies, numerical modelling, observations from satellite and ground-based missions are welcome. In particular, we encourage presentations using data from MMS, THEMIS, Van Allen Probes, Arase (ERG), Cluster, cube-sat missions, Juno, SuperDARN, magnetometer, optical imagers, IS-radars and ground-based VLF measurements.

Convener: Dedong WangECSECS | Co-conveners: Hayley AllisonECSECS, Ondrej Santolik, Chao YueECSECS, Qiugang Zong
vPICO presentations
| Thu, 29 Apr, 09:00–11:45 (CEST)

This interdisciplinary session welcomes contributions on novel conceptual and/or methodological approaches and methods for the analysis and statistical-dynamical modeling of observational as well as model time series from all geoscientific disciplines.
Methods to be discussed include, but are not limited to linear and nonlinear methods of time series analysis. time-frequency methods, statistical inference for nonlinear time series, including empirical inference of causal linkages from multivariate data, nonlinear statistical decomposition and related techniques for multivariate and spatio-temporal data, nonlinear correlation analysis and synchronisation, surrogate data techniques, filtering approaches and nonlinear methods of noise reduction, artificial intelligence and machine learning based analysis and prediction for univariate and multivariate time series.
Contributions on methodological developments and applications to problems across all geoscientific disciplines are equally encouraged. We particularly aim at fostering a transfer of new methodological data analysis and modeling concepts among different fields of the geosciences.


Sub-Session "Mathematical Climatology and Space-time Data Analysis" (Abdel Hannachi, Amro Elfeki, Christian Franzke, Muhammad Latif, Carlos Pires)

The recent progress in mathematical methods to solve various problems in weather & climate nonlinear dynamics and data analysis calls for the need to develop a new session that focus on those methods. Novel and powerful mathematical methods have been developed and used in different subjects of climate. Because those methods are used within specific contexts they go unnoticed most of the time by climate researchers. The proposed new session will provide the opportunity to climate scientists and researchers working on developing mathematical methods for climate to come together and present their findings in a transparent way. This will also be easily accessible to other climate scientists who look for, and are interested in specific methods to solve their problems.
Contributions are encouraged from researchers working on mathematical methods and their application to weather and climate. We particularly welcome contributions on optimization, dimension reduction and data mining, space-time patterns identification, machine learning, statistical prediction modelling, nonlinear methods , Bayesian statistics, and Monte-Carlo Markov Chain (MCMC) methods in stochastic modelling.

Co-organized by BG2/CL5.2/ESSI1/GI2/HS3/SM3/ST2
Convener: Reik Donner | Co-conveners: Tommaso Alberti, Giorgia Di Capua, Federica GugoleECSECS, Andrea Toreti
vPICO presentations
| Thu, 29 Apr, 09:00–10:30 (CEST)

Most often observations and measurements of geophysical systems and dynamical phenomena are obtained as time series whose dynamics usually manifests a nonlinear behavior. During the past decades, nonlinear approaches in geosciences have rapidly developed to gain novel insights on fluid dynamics, greatly improving weather forecasting, on turbulence and stochastic behaviors, on the development of chaos in dynamical systems, and on concepts of networks, nowadays frequently employed in climate research.

In this short course, we will offer a broad overview of the development and application of nonlinear concepts across the geosciences in terms of recent successful applications from various fields, ranging from climate to solar-terrestrial relations. The focus will be on a comparison between different methods to investigate various aspects of both known and unknown physical processes, moving from past accomplishments to future challenges.

Public information:
Speakers and topics

Peter Ditlevsen: "The climate history as a time series: How do we dissect it?"
Tommaso Alberti: "A voyage through scales: the myth of turbulence"
Reik Donner: "Internal versus forced variability: Complexity and causality perspectives on space weather"
Co-organized by CL6/EMRP2/NH11/ST2
Convener: Tommaso Alberti | Co-conveners: Peter Ditlevsen, Reik Donner
Wed, 28 Apr, 10:00–11:00 (CEST)

This session primarily focuses on the neutral atmospheres of terrestrial bodies other than the Earth. This includes not only Venus and Mars, but also exoplanets with comparable envelopes and satellites carrying dense atmospheres such as Titan or exospheres such as Ganymede. We welcome contributions dealing with processes affecting the atmospheres of these bodies, from the surface to the exosphere. We invite abstracts concerning observations, both from Earth or from space, modeling and theoretical studies, or laboratory work. Comparative planetology abstracts will be particularly appreciated.

Co-organized by AS4/ST2
Convener: Arnaud BethECSECS | Co-conveners: Arianna Piccialli, Jan Vatant d'OlloneECSECS
vPICO presentations
| Thu, 29 Apr, 09:00–11:45 (CEST)

Various space agencies around the world, the scientific community, and industrial partners are currently making advancements with a number of anticipated missions to the Moon, Mars, and other Solar System bodies. Each mission has a unique set of goals that calls for strategically selected instruments accommodating a diverse set of platforms, such as but not limited to, rovers, orbiters, and human explorers. This session invites presentations on a broad topic of future planetary missions and instruments, including those already in development. Our aim is to share latest progress, discuss preflight scientific results, and increase awareness for potential cooperation.

Co-organized by GI3/ST2
Convener: Gen ItoECSECS | Co-conveners: Casey HonniballECSECS, Susanne Schröder, Elliot Sefton-Nash
vPICO presentations
| Wed, 28 Apr, 09:00–10:30 (CEST)

ST3 – Ionosphere and Thermosphere

Programme group scientific officer: Dalia Buresova


The Earth's ionosphere embedded in the thermosphere is a coupled system influenced by solar and magnetospheric processes from above, as well as by upward propagating disturbances from below. This open session is suitable for contributions on all aspects of ionospheric and thermospheric physics. The session invites (multi)instrumental ground-based and satellite observations, simulations and modelling studies that address the dynamics of the ionosphere, concerning transient events, plasma waves and irregularities, as well as large-scale dynamics and long-term variations. Contributions dealing with magnetospheric forcing are sought in the areas of ionospheric disturbances caused by CME- and CIR/CH HSS-related magnetic storms and substorms. New results that focus on investigation of latitudinal, seasonal and hemispherical effects of the storms and substorms on ionosphere are especially appreciated. Also results of investigation of the effects of other sources on ionospheric variability, such as solar terminator, solar eclipse, seismic activity, are welcome. As for atmospheric forcing, contributions are sought that focus on atmospheric waves, wave-wave and wave-mean flow interactions, atmospheric electricity and electrodynamical coupling processes. New results on MLT feeding (wave penetration and secondary wave generation) of ionospheric disturbances and the solar effect on the vertical propagation conditions of the atmospheric waves are welcome.

Convener: Dalia Buresova | Co-conveners: David Altadill, Chao Xiong, Veronika Barta
vPICO presentations
| Wed, 28 Apr, 14:15–17:00 (CEST)

Earth’s atmosphere-ionosphere system is a stratified and vertically structured mix of gases that comprise different layers, i.e., the troposphere, stratosphere, mesosphere, and thermosphere, and its ionized part, the ionosphere. These layers are characterized by different combinations of dynamics, e.g., fluid-dynamic, chemical, and electrodynamical processes. The processes are coupled through various mechanisms, e.g., atmospheric circulations, disturbances, and various waves. The current session emphasizes the recent investigations of processes driving or reflecting vertical coupling within the atmosphere-ionosphere system in a broad range of spatial and temporal scales, such as atmospheric and ionospheric response to various waves (planetary waves, tides, gravity waves, etc.), transient phenomena (sudden stratospheric warming, seasonal transition), recurring patterns like QBO and ENSO, long-term trends in the middle and upper atmosphere and their drivers, and the relative importance of atmospheric and solar/magnetospheric forcing in the upper and middle atmosphere. This session invites contributions that discuss relevant methodologies, theory, modeling, experiment, and observations of different aspects of atmosphere-ionosphere coupling.

Public information:
Presenting authors and participants can assess the live session page through a button of "Enter live session" at https://meetingorganizer.copernicus.org/EGU21/session/40163 when the session is active, after about 13:00—13:15 Central European Time (GMT+2) on Friday. On the live session page, a Zoom session will be active. The Zoom session comprises two parts: the authors' talks and the interactions between authors and participants. For the talks, a conference assistant will show pre-uploaded and pre-recorded slides/presentations, while authors are supposed to give their talks using the slides under the control of the conference assistant. There will be no questions between different talks. The interactions are based on the "Breakout rooms" function in the Zoom Meeting (e.g., https://www.youtube.com/watch?v=3UB7j2JDWyw). We strongly recommend that you download the Zoom client (version 5.3.0 or higher). If you join Zoom through a browser, you must ask the assistant in the Zoom Meeting to assign you to breakout rooms by, e.g., writing to the assistant through chat in the meeting.

We are looking forward to meeting you in the Zoom session.

Maosheng He, Yosuke Yamazaki, Larisa Goncharenko
Convener: Maosheng He | Co-conveners: Yosuke Yamazaki, Larisa Goncharenko
vPICO presentations
| Fri, 30 Apr, 13:30–15:00 (CEST)

Plasma density irregularities can occur at all latitudes in the Earth’s ionosphere. However, the onset and evolution of these irregularities as well as their influence on the radio wave signals continue to be unsolved scientific questions. The various proposed generation mechanisms, including instability growth rates and seeding processes, are strongly coupled to the neutral atmosphere and magnetospheric dynamics, making the forecasting of ionospheric irregularities much more challenging. Recent observations from ground- and space-based measurements, as well as new innovative data analysis and modeling techniques, e.g., data assimilation and machine learning, have the potential to advance our understanding of the ionospheric irregularities. Studies that focus on the observation, modeling and prediction of plasma irregularities of different scales are welcome at this session. The mitigation of negative effects and recent developments to forecast scintillation effects on Global Navigation Satellite or other communication systems are also of high interest.

Convener: Chao Xiong | Co-conveners: Lucilla Alfonsi, Jens Berdermann, Yaqi Jin, Jeffrey Klenzing
vPICO presentations
| Fri, 30 Apr, 15:30–17:00 (CEST)

This session is devoted to the analysis of very low/low frequency (VLF/LF) techniques applied to investigate ionospheric disturbances related to natural and technological hazards. Such disturbances lasting from several milliseconds to several days can be used to study natural disasters occurring before, during and after the main event. The capability of the VLF/LF radio waves (3 kHz – 300 kHz) leads the remote sensing of the ionosphere due to the relatively low path attenuation of such frequencies allowing propagation over long distances. The purpose of this session is to provide a forum for discussion among researchers involved in studies of natural hazards like earthquakes, volcano activity, tropical cyclones and lightning, as well as in studies of technological hazards induced by high-energy solar radiation by means of VLF/LF detection system. We encourage contributions on the studies of ionospheric disturbances detected by ground-based networks like International Network for Frontier Research on Earthquake Precursors (INFREP) in Europe, South America VLF NETwork (SAVNET) in South America, World Wide Lightning Location Network (WWLLN) and others. We welcome new methods and techniques applied for the detections and the processing of the VLF/LF signals. Particular attention is given to the comprehension of the physical mechanisms at the origin of precursor signals observed before the natural hazards occurrence.

Co-organized by AS5/ST3
Convener: Giovanni Nico | Co-conveners: Pier Francesco Biagi, Mohammed Y. Boudjada, Aleksandra NinaECSECS
vPICO presentations
| Thu, 29 Apr, 09:45–10:30 (CEST)

The scope of this session covers all aspects of dwarf planets and small solar system objects, including comets, asteroids, meteoroids, and dust. Topics are not limited to but include dynamics, evolution, physical properties, and interactions. The presenters are invited to highlight results obtained from space missions, observations, laboratory studies, theory, and numerical simulations. This session also provides a forum for presenting future space instrumentation. We encourage presenting the research results taking into account the multi-disciplinarity of the field.

Co-organized by ST3
Convener: Jiri Pavlu | Co-conveners: Maria Gritsevich, Ingrid Mann
vPICO presentations
| Thu, 29 Apr, 14:15–17:00 (CEST)

Rocky planets are complex systems. Their evolution is dependent on a wide array of different mechanisms and how they interact together. Interactions between the interior and atmosphere of rocky planets are modulated by the planets’ bulk composition, which in turn is linked to the chemical properties of their host stars. The coupling between different layers of terrestrial planets and feedback processes are important to understand the interdependent evolution of bulk, interiors, surfaces, and atmospheres. How diverse is the physical and chemical parameter space of rocky planets within and beyond our Solar System? What constraints can be placed on the range of possible compositions of terrestrial exoplanets? How do surface-interior interactions shape atmospheric properties of rocky planets in general? How do changes in surface temperature affect surface alteration processes as well as volatile exchanges?

We welcome contributions focused on a single terrestrial body as well as from comparative planetology. Both exoplanets and solar system bodies are covered. This session will bring together scientists from a wide range of domains – geodynamics, geochemistry, cosmochemistry, as well as astrophysics – to examine physical and chemical links between stars and planets and between interiors and atmospheres, as well as their interdependent evolution and implications for exoplanet biosignatures.

Co-organized by GD9/ST3
Convener: Haiyang Wang | Co-conveners: Gregor Golabek, Caroline Dorn, Cedric Gillmann, Dan Bower, Alison Hunt
vPICO presentations
| Mon, 26 Apr, 15:30–17:00 (CEST)

This joint session invites papers that are related to the mesosphere and lower thermosphere. It addresses the topical fields of the PRESTO (Predictability of the Solar-Terrestrial Coupling) program initiated by SCOSTEP, focusing on the role of the sun and the middle atmosphere/thermosphere/ionosphere in climate and space weather. Contributions studying radiation, chemistry, energy balance, atmospheric tides, planetary waves, gravity waves, neutral-ion coupling, and the interaction of the various processes involved are welcome. This includes work on model data as well as measurements from satellites and ground based platforms such as ALOMAR.

Co-organized by ST3
Convener: Martin Kaufmann | Co-conveners: Franz-Josef Lübken, Peter Preusse
vPICO presentations
| Thu, 29 Apr, 09:00–11:45 (CEST)

ST4 – Space Weather and Space Climate

Programme group scientific officer: Olga Malandraki


Solar Irradiance is the key energy input to Earth. A positive Earth Energy Imbalance (EEI) is the energy, which is continuously stored by the Earth and will ultimately be released to the atmosphere, causing global warming. In order to determine its exact value both the Total Solar Irradiance (TSI) and the Top of the Atmosphere (ToA) Outgoing Radiation (TOR) need to be measured with unprecedented accuracy and precision. However, so far, the EEI could not be determined as the measurements were not sufficiently accurate. This calls for improved instrument technologies as well as a traceable calibration chain of the space instrumentation. In this session we invite contributions on the both the measurement of solar irradiance as well as the Earth outgoing radiation which ultimately aim to pave the way to determine EEI from space.

Co-organized by CL5.1
Convener: Margit Haberreiter | Co-conveners: W. H. Swartz, Ping Zhu
vPICO presentations
| Thu, 29 Apr, 11:45–12:30 (CEST)

Space weather and space climate are collective terms that describe the Sun-Earth system interactions on timescales varying between minutes and decades and include processes at the Sun, in the heliosphere, magnetosphere, ionosphere, thermosphere and at the lower atmosphere. Being able to predict (forecast and nowcast) the extreme events and develop the strategy for mitigation are vital as the space assets and critical infrastructures, such as communication and navigation systems, power grids, and aviation, are all extremely sensitive to the external environment. Post-event analysis is crucially important for the development and maintenance of numerical models, which can predict extreme space weather events in order to avoid failure of the critical infrastructures.

This session aims to address both the current state of the art of space weather products and new ideas and developments that can enhance the understanding of space weather and space climate and its impact on critical infrastructure. We invite presentations on various space weather and space climate-related activities in the Sun-Earth system: forecast and nowcast products and services; satellite observations; model development, validation, and verification; data assimilation; development and production of geomagnetic and ionospheric indices. Talks on space weather effects on applications (e.g. on airlines, pipelines and power grids, space flights, auroral tourism, etc.) in the Earth’s environment are also welcomed.

Convener: Guram Kervalishvili | Co-conveners: Yulia Bogdanova, Claudia Borries, Therese Moretto Jorgensen, Alan Thomson
vPICO presentations
| Thu, 29 Apr, 13:30–17:00 (CEST)

Coronal mass ejections (CMEs), interplanetary shocks, corotating interaction regions (CIRs) and solar energetic particles (SEPs) drive heliospheric variability, causing various interplanetary as well as planetary disturbances. Therefore, the prediction of their arrival and impact is extremely important for the modern space-exploration and electronics-dependent society. Significant efforts have been made in the past decade to develop and improve the prediction capabilities, through both state-of-the art observations and modelling. Although significant progress has been made, many new challenges have been revealed. We are limited in obtaining reliable observation-based input for the models, tracking solar wind transients throughout the heliosphere and reliably evaluating prediction models. These challenges can be tackled by exploiting and improving our existing capabilities, as well as using the out-of-the-box thinking and break from the traditional methods.

This session is devoted to provide the overview of the current state of the space weather prediction of the arrival time and impact of various solar wind transients and to introduce new and promising observational and modelling capabilities. We solicit abstracts on observational and modelling efforts, as well as space weather prediction evaluation. With the overview of our current capabilities and possible future prospects we aim to highlight guidelines to the general direction of the future scientific efforts, as well as space-mission planning.

Convener: Mateja DumbovicECSECS | Co-conveners: Tanja AmerstorferECSECS, Dario Del Moro, Evangelos Paouris
vPICO presentations
| Wed, 28 Apr, 15:30–17:00 (CEST)

Originally the term ‘space weather’ referred to the way in which “the variable conditions on the Sun can influence, throughout space and in the Earth’s magnetic field and upper atmosphere, the performance of space-borne and ground-based technological systems and endanger human life or health”(1). In the last years it has been extended to all the objects of the Solar Systems, becoming “Planetary Space Weather”.
The different aspects of the interactions induced by the Sun with the many objects of the Solar System should be studied in comparison with the Earth case, to help understanding the processes involved. In fact, possible comparative studies have already proven to be a powerful tool in understanding the different effects and interactions of space weather occurring around all the bodies of the Solar System.
In the present session, we welcome abstracts from all planets’ upstream solar wind activities and their relation to planetary space weather, including especially magnetized bodies (like Mercury, the Earth, Saturn and Jupiter) as well as comparisons with unmagnetized bodies (Mars and Venus).
Since in these years many operative missions have among their science goals the planetary space weather, such as BepiColombo that will have soon two Venus Flybys and then six Mercury flybys, or Solar Orbiter that will have diverse Venus flybys as well, special focus of this session will be on Venus and Mercury and on the possible studies related to multi spacecraft observations.
In this frame, we welcome studies on:
• magnetosphere-ionosphere coupling dynamics (and auroras where present);
• the solar wind interaction with planets and moons
• inter-comparisons of planetary environments;
• observations of space weather effects from space probes and Earth-based instrumentation;
• theoretical modeling and simulations, especially in view of measurement analysis and interpretation;
• potential impacts of space weathering on technological space systems.

Co-organized by ST4
Convener: Philippe Garnier | Co-conveners: Markus Fränz, Anna Milillo, Zhonghua Yao
vPICO presentations
| Thu, 29 Apr, 13:30–14:15 (CEST)

The ionospheres and (induced) magnetospheres of unmagnetized and weakly magnetized bodies with substantial atmospheres (e.g. Mars, Venus, Titan, Pluto and comets) are subject to disturbances due to solar activity, interplanetary conditions (e.g. solar flares, coronal mass ejections and solar energetic particles) or for moons parent magnetospheric activity. They interact similarly as their magnetized counterparts but with scientifically important differences.
As an integral part of planetary atmospheres, ionospheres are tightly coupled with the neutral atmosphere, exosphere and surrounding plasma environment, possessing rich compositional, density, and temperature structures. The interaction among neutral and charged components affects atmospheric loss, neutral winds, photochemistry, and energy balance within ionospheres.
This session invites abstracts concerning remote and in-situ data analysis, modelling studies, comparative studies, instrumentation and mission concepts for unmagnetized and weakly magnetized solar system bodies.

Co-organized by ST4
Convener: Martin Volwerk | Co-conveners: Charlotte Götz, Pierre Henri
vPICO presentations
| Thu, 29 Apr, 11:45–12:30 (CEST)

The Earth’s magnetic field is continuously monitored by a large number of geomagnetic observatories and satellites in low Earth orbit. The use of these measurements can play a significant role in the space weather era. They can be used to monitor space weather events, such as magnetic storms, substorms and geomagnetically induced currents, and furthermore they facilitate studies of dynamic solar-terrestrial events and of their interactions. These measurements can also be used to model the magnetic field of external origin which poses presently the largest problem for progress in geomagnetic field modeling.
The aim of this session is to collect new ideas and results on how magnetic field measurements (from geomagnetic observatories and satellites such as CHAMP, Swarm, CSES, ePOP and so on) can improve our knowledge in the space weather domain.

Co-organized by ST4
Convener: Paola De Michelis | Co-conveners: Ioannis A. Daglis, Mioara Mandea
vPICO presentations
| Tue, 27 Apr, 11:00–12:30 (CEST)