A self-consistent simulation of proton acceleration and transport near a high-speed solar wind stream

Solar wind stream interaction regions (SIRs)&#160; are often characterised by energetic ion enhancements. The mechanisms accelerating these particles as well as the locations where the acceleration occurs, remains debated. Here, we report the findings of a simulation of a SIR-event observed by Parker Solar Probe at 0.56 au and the Solar Terrestrial Relations Observatory-Ahead at 0.96 au in September 2019 when both spacecraft were approximately radially aligned with the Sun. The simulation reproduces the solar wind configuration and the energetic particle enhancements observed by both spacecraft. Our results show that the energetic particles are produced at the compression waves associated with the SIR and that the suprathermal tail of the solar wind is a good candidate to provide the seed population for particle acceleration. The simulation confirms that the acceleration process does not require shock waves and can already commence within Earth's orbit, with an energy dependence on the precise location where particles are accelerated. The three-dimensional configuration&#160; of the solar wind streams strongly modulates the energetic particle distributions, illustrating the necessity of advanced models to understand&#160; these particle events.This research has received funding from the European Union&#8217;s Horizon 2020 research and innovation programme under grant agreement No 870405 (EUHFORIA 2.0).&#160;

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Coordinated observations of relativistic electron enhancements following an HSS period

10.5194/egusphere-egu21-11753 ◽

2021 ◽

Author(s):

Afroditi Nasi ◽

Ioannis A. Daglis ◽

Christos Katsavrias ◽

Ingmar Sandberg ◽

Wen Li ◽

...

Keyword(s):

Solar Wind ◽

Relativistic Electron ◽

High Speed ◽

Geomagnetic Storms ◽

Wind Pressure ◽

The European Union ◽

Horizon 2020 ◽

Research And Innovation ◽

Wave Measurements ◽

Substorm Activity

During the second half of 2019, a sequence of solar wind high-speed streams (VSW &#8805; 600 km/s)&#160; impacted the magnetosphere, resulting in a series of recurrent, relatively weak, geomagnetic storms (Dstmin &#8805; - 80 nT). During one of these storms, a longer-lasting solar wind pressure pulse and intense substorm activity were also recorded (AL &#8804; - 1600 nT on August 31 and September 1).We use particle measurements from the Van Allen Probes, Arase and Galileo 207, 215 satellites, to investigate this event; all spacecraft observed a significant enhancement of relativistic electron fluxes. We also use ULF and chorus wave measurements, as well as interplanetary parameters, for a detailed investigation of this event and of the acceleration mechanisms involved.This work has received funding from the European Union&#8217;s Horizon 2020 research and innovation programme under grant agreement No 870437 for the SafeSpace project.

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The three-dimensional extent of a high speed solar wind stream

Space Science Reviews ◽

10.1007/bf00768767 ◽

1995 ◽

Vol 72 (1-2) ◽

pp. 125-128 ◽

Cited By ~ 3

Author(s):

R. J. Macdowall ◽

M. D. Desch ◽

M. L. Kaiser ◽

R. G. Stone ◽

R. A. Hess ◽

...

Keyword(s):

Solar Wind ◽

High Speed ◽

Three Dimensional ◽

Solar Wind Stream ◽

Speed Solar Wind ◽

High Speed Solar Wind

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The Three-Dimensional Extent of a High Speed Solar Wind Stream

The High Latitude Heliosphere ◽

10.1007/978-94-011-0167-7_22 ◽

1995 ◽

pp. 125-128

Author(s):

R. J. Macdowall ◽

M. D. Desch ◽

M. L. Kaiser ◽

R. G. Stone ◽

R. A. Hess ◽

...

Keyword(s):

Solar Wind ◽

High Speed ◽

Three Dimensional ◽

Solar Wind Stream ◽

Speed Solar Wind ◽

High Speed Solar Wind

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Improving CME evolution and arrival predictions with AMR and grid stretching in EUHFORIA

10.5194/egusphere-egu21-9193 ◽

2021 ◽

Author(s):

Tinatin Baratashvili ◽

Christine Verbeke ◽

Nicolas Wijsen ◽

Emmanuel Chané ◽

Stefaan Poedts

Keyword(s):

Solar Wind ◽

Adaptive Mesh Refinement ◽

Adaptive Mesh ◽

Mhd Equations ◽

Efficiency Gain ◽

The European Union ◽

Interplanetary Shocks ◽

Horizon 2020 ◽

Research And Innovation ◽

Speed Up

Coronal Mass Ejections (CMEs) are the main drivers of interplanetary shocks and space weather disturbances. Strong CMEs directed towards Earth can cause severe damage to our planet. Predicting the arrival time and impact of such CMEs can enable to mitigate the damage on various technological systems on Earth.&#160;We model the inner heliospheric solar wind and the CME propagation and evolution within a new heliospheric model based on the MPI-AMRVAC code. It is crucial for such a numerical tool to be highly optimized and efficient, in order to produce timely forecasts. Our model solves the ideal MHD equations to obtain a steady state solar wind configuration in a reference frame corotating with the Sun. In addition, CMEs can be modelled by injecting a cone CME from the inner boundary (0.1 AU).Advanced techniques, such as grid stretching and Adaptive Mesh Refinement (AMR) are employed in the simulation. Such methods allow for high(er) spatial resolution in the numerical domain, but only where necessary or wanted. As a result, we can obtain a detailed, highly resolved image at the (propagating) shock areas, without refining the whole domain.These techniques guarantee more efficient simulations, resulting in optimised computer memory usage and a significant speed-up. The obtained speed-up, compared to the original approach with a high-resolution grid everywhere, varies between a factor of 45 - 100 depending on the domain configuration. Such efficiency gain is momentous for the mitigation of the possible damage and allows for multiple simulations with different input parameters configurations to account for the uncertainties in the measurements to determine them. The goal of the project is to reproduce the observed results, therefore, the observable variables, such as speed, density, etc., are compared to the same type of results produced by the existing (non-stretched, single grid) EUropean Heliospheric FORecasting Information Asset (EUHFORIA) model and observational data for a particular event on 12th of July, 2012. The shock features are analyzed and the results produced with the new heliospheric model are in agreement with the existing model and observations, but with a significantly better performance.&#160;&#160;This research has received funding from the European Union&#8217;s Horizon 2020 research and innovation programme under grant agreement No 870405 (EUHFORIA 2.0).

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Predicting geo-effectiveness of CMEs using a novel 3D CME model FRi3D integrated into EUHFORIA

10.5194/egusphere-egu21-11605 ◽

2021 ◽

Author(s):

Stefaan Poedts ◽

Anwesha Maharana ◽

Camilla Scolini ◽

Alexey Isavnin

Keyword(s):

Magnetic Field ◽

Solar Wind ◽

Field Strength ◽

Magnetic Field Strength ◽

Three Dimensional ◽

Flux Rope ◽

Future Perspective ◽

The European Union ◽

Horizon 2020 ◽

The Magnetic Field

Previous studies of Coronal Mass Ejections (CMEs) have shown the importance of understanding their geometrical structure and internal magnetic field configuration for improving forecasting at Earth. The precise prediction of the CME shock and the magnetic cloud arrival time, their magnetic field strength and the orientation upon impact at Earth is still challenging and relies on solar wind and CME evolution models and precise input parameters. In order to understand the propagation of CMEs in the interplanetary medium, we need to understand their interaction with the complex features in the magnetized background solar wind which deforms, deflects and erodes the CMEs and determines their geo-effectiveness. Hence, it is important to model the internal magnetic flux-rope structure in the CMEs as they interact with CIRs/SIRs, other CMEs and solar transients in the heliosphere. The spheromak model (Verbeke et al. 2019) in the heliospheric wind and CME evolution simulation EUHFORIA (Pomoell and Poedts, 2018), fits well with the data near the CME nose close to its axis but fails to predict the magnetic field in CME legs when these impact Earth (Scolini et al. 2019). Therefore, we implemented the FRi3D stretched flux-rope CME model (Isavnin, 2016) in EUHFORIA to model a more realistic CME geometry. Fri3D captures the three-dimensional magnetic field structure with parameters like skewing, pancaking and flattening that quantify deformations experienced by an interplanetary CME. We perform test runs of real CME events and validate the ability of FRi3D coupled with EUHFORIA in predicting the CME geo-effectiveness. We have modeled two real events with FRi3D. First, a CME event on 12 July 2012 which was a head-on encounter at Earth. Second, the flank CME encounter of 14 June 2012 which did not leave any magnetic field signature at Earth when modeled with Spheromak. We compare our results with the results from non-magnetized cone simulations and magnetized simulations employing the spheromak flux-rope model. We further discuss how constraining observational parameters using the stretched flux rope CME geometry in FRi3D affects the prediction of the magnetic field strength in our simulations, highlighting improvements and discussing future perspective.This research has received funding from the European Union&#8217;s Horizon 2020 research and innovation programme under grant agreement No 870405 (EUHFORIA 2.0)

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Modeling the Sun – Earth propagation of solar disturbances for the H2020 SafeSpace project

10.5194/egusphere-egu21-10796 ◽

2021 ◽

Author(s):

Benoit Lavraud ◽

Rui Pinto ◽

Rungployphan Kieokaew ◽

Evangelia Samara ◽

Stefaan Poedts ◽

...

Keyword(s):

Solar Wind ◽

Interplanetary Space ◽

Coronal Magnetic Field ◽

Physical Parameters ◽

The European Union ◽

Horizon 2020 ◽

Research And Innovation ◽

Reconstruction Methods ◽

Solar Disturbances ◽

Magnetic Field Computation

We present the solar wind forecast pipeline that is being implemented as part of the H2020 SafeSpace project. The Goal of this project is to use several tools in a modular fashion to address the physics of Sun &#8211; interplanetary space &#8211; Earth&#8217;s magnetosphere. This presentation focuses on the part of the pipeline that is dedicated to the forecasting &#8211; from solar measurements &#8211; of the solar wind properties at the Lagrangian L1 point. The modeling pipeline puts together different mature research models: determination of the background coronal magnetic field, computation of solar wind acceleration profiles (1 to 90 solar radii), propagation across the heliosphere (for regular solar wind, CIRs and CMEs), and comparison to spacecraft measurements. Different magnetogram sources (WSO, SOLIS, GONG, ADAPT) can be combined, as well as coronal field reconstruction methods (PFSS, NLFFF), wind (MULTI-VP) and heliospheric propagation models (CDPP 1D MHD, EUHFORIA). We aim at providing a web-based service that continuously supplies a full set of bulk physical parameters of the solar wind at 1 AU several days in advance, at a time cadence compatible with space weather applications. This work has received funding from the European Union&#8217;s Horizon 2020 research and innovation programme under grant agreement No 870437.

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The Dynamic Time Warping as a means to assess modeled solar wind time series

10.5194/egusphere-egu21-12459 ◽

2021 ◽

Author(s):

Evangelia Samara ◽

Emmanuel Chane ◽

Brecht Laperre ◽

Christine Verbeke ◽

Manuela Temmer ◽

...

Keyword(s):

Time Series ◽

Solar Wind ◽

Dynamic Time Warping ◽

Optimal Alignment ◽

The European Union ◽

Time Warping ◽

Horizon 2020 ◽

Research And Innovation ◽

Single Number ◽

Dynamic Time

In this work, the Dynamic Time Warping (DTW) technique is presented as an alternative method to assess the performance of modeled solar wind time series at Earth (or at any other point in the heliosphere). This method can quantify how similar two time series are by providing a temporal alignment between them, in an optimal way and under certain restrictions. It eventually estimates the optimal alignment between an observed and a modeled series, which we call the warping path, by providing a single number, the so-called DTW cost. A description on the reasons why DTW should be applied as a metric for the assessment of solar wind time series, is presented. Furthermore, examples on how exactly the technique is applied to our modeled solar wind datasets with EUHFORIA, are shown and discussed.This project has received funding from the European Union&#8217;s Horizon 2020 research and innovation programme under grant agreement No 870437 (SafeSpace).

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Mercury’s exospheric model for SPIDER

10.5194/egusphere-egu21-7583 ◽

2021 ◽

Author(s):

Martina Moroni ◽

Alessandro Mura ◽

Anna Milillo ◽

Andrè Nicolas

Keyword(s):

Solar Wind ◽

Solar System ◽

Three Dimensional ◽

Numerical Data ◽

Release Mechanism ◽

Three Dimensional Model ◽

Horizon 2020 ◽

Research And Innovation ◽

Area Of Interest ◽

Loss Mechanisms

<div> The propagation of Solar events and the response of planetary environment is a fundamental area of interest in the study of the solar system, object of several models and tools for data analysis. In the framework of the starting Europlanet-2024 program, the Virtual Activity (VA) SPIDER (Sun-Planet Interactions Digital Environment on Request) aims a publicly available and sophisticated services, in order to model planetary environments and solar wind interactions. One of these services is focused on the prototype for the model of the Mercury exosphere, in particular to study its exospheric density and the solar wind precipitation to the surface. Mercury is a unique case in the solar system: absence of an atmosphere and the weakness of the intrinsic magnetic field. The Hermean exosphere is continuously eroded and refilled by interactions with plasma and surface, so the environment is considered as a single, unified system &#8211; surface- exosphere-magnetosphere. &#160;The study of the generation mechanisms, the compositions and the configuration of the Hermean exosphere will provide crucial insight in the planet status and evolution. </div><div> The MESSENGER/NASA mission visited Mercury in the period 2008-2015, adding a consistent amount of data but a global description of planet&#8217;s exosphere is still not available; the ESA BepiColombo mission will study Mercury orbiting around the planet from 2025. For this reason, it is important to have a modelling tool ready for interpreting observational data and testing different hypothesis on release mechanism.&#160; Considering different generation and loss mechanisms, we present a Monte Carlo three-dimensional model of the Hermean exosphere, that considers all the major sources and loss mechanisms. In fact, this numerical model includes among the processes responsible of the formation of such an exosphere the ion sputtering (IS), the thermal desorption (TD), the photon-stimulated desorption (PSD) and micro-meteoroids impact vaporization (MMIV) from the planetary surface. The model calculates the trajectories of ejected particles from which we obtain the spatial and energy distributions of atmospheric particles. Furthermore, an analytical model is obtained by fitting the numerical data with parametric functions. In this way, it is possible to model the exosphere of Mercury for each source separately and we can investigate the role of each physical source independently of the others. &#160; </div><div> Here we present the web-based interface of the model and the functionalities of this infrastructure that is being implemented in SPIDER. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 871149. </div>

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Using machine learning to identify magnetic reconnection in two-dimensional simulations

10.5194/egusphere-egu2020-12160 ◽

2020 ◽

Author(s):

Andong Hu ◽

Jannis Teunissen ◽

Manuela Sisti ◽

Francesco Califano ◽

Jérémy Dargent ◽

...

Keyword(s):

Machine Learning ◽

Solar Wind ◽

Magnetic Reconnection ◽

Solar Wind Plasma ◽

Space Physics ◽

Electron Velocity ◽

Two Dimensional ◽

The European Union ◽

Horizon 2020 ◽

Research And Innovation

<div>The understanding of fundamental processes at play in a collisionless plasmas such as the solar wind, is a frontier problem in space physics. We investigate here the occurrence of magnetic reconnection in a plasma with parameters corresponding to solar wind plasma and its interplay with a fully-developed turbulent state. Ongoing magnetic reconnection can, at the moment, be accurately identified only by humans. Therefore, as a first step, the goal of this study is to present a new method to automatically recognise reconnection events in the output of two-dimensional HVM (Hybrid Vlasov Maxwell)&#160;simulations&#160;where ions evolve by solving the Vlasov equation and the electrons are treated as a fluid with mass. A large dataset with labelled reconnection events was prepared, including parameters such as the magnetic field, the electron velocity field and the current density. We consider two types of machine learning models: classical approaches using on physics-based features, and convolutional neural networks (CNNs). We will investigate which approach performs better, and which input variables are most relevant. In addition, we will try to categorize magnetic reconnection regions (current sheets). This work has received funding from the European Union&#8217;s Horizon 2020 research and innovation programme under grant agreement No 776262 (AIDA, www.aida-space.eu).</div>

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Monitoring and assessment of an oil spill event with very high resolution tools.

10.5194/egusphere-egu21-13528 ◽

2021 ◽

Author(s):

Ana M. Mancho ◽

Guillermo García-Sánchez ◽

Antonio G. Ramos ◽

Josep Coca ◽

Begoña Pérez-Gómez ◽

...

Keyword(s):

High Resolution ◽

Oil Spill ◽

In Situ Observation ◽

The European Union ◽

Horizon 2020 ◽

Research And Innovation ◽

Port Authorities ◽

Different Sources ◽

Very High

This presentation discusses a downstream application from Copernicus Services, developed in the framework of the IMPRESSIVE project, for the monitoring of &#160;the oil spill produced after the crash of the ferry &#8220;Volcan de Tamasite&#8221; in waters of the Canary Islands on the 21st of April 2017. The presentation summarizes the findings of [1] that describe a complete monitoring of the diesel fuel spill, well-documented by port authorities. Complementary information supplied by different sources enhances the description of the event. We discuss the performance of very high resolution hydrodynamic models in the area of the Port of Gran Canaria and their ability for describing the evolution of this event. Dynamical systems ideas support the comparison of different models performance. Very high resolution remote sensing products and in situ observation validate the description.Authors acknowledge support from IMPRESSIVE a project funded by the European Union&#8217;s Horizon 2020 research and innovation programme under grant agreement No 821922. SW acknowledges the support of ONR Grant No. N00014-01-1-0769References[1] G.Garc&#237;a-S&#225;nchez, A. M. Mancho, A. G. Ramos, J. Coca, B. P&#233;rez-G&#243;mez, E. &#193;lvarez-Fanjul, M. G. Sotillo, M. Garc&#237;a-Le&#243;n, V. J. Garc&#237;a-Garrido, S. Wiggins. Very High Resolution Tools for the Monitoring and Assessment of Environmental Hazards in Coastal Areas. &#160;Front. Mar. Sci. (2021) doi: 10.3389/fmars.2020.605804.

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