Displays

Rapid storm-time geomagnetic disturbances, typically at sub-auroral latitudes, have been recognized as one of the most detrimental space weather phenomena, potentially leading to damage to and outage of critical power infrastructure. We can show that sub-auroral magnetic spikes in storms (of the order of 1000 nT/min) do resemble in their appearance and spatio-temporal behavior small but intense and very short-lived substorms, including three-dimensional current wedge and electrojet-enhancement formation. Statistically these spikes do occur at all local times, but preferably pre-midnight and around 0600 MLT in the morning sector, which is only partially in agreement with the substorm analogy, and indicate that there may indeed be several mechanisms at work. We will present results from event and statistical studies to clarify the physical characteristics and potential drivers for these potentially most damaging geomagnetic disturbances in the SWx realm.

How to cite: Opgenoorth, H. J., Schilling, A., and Hamrin, M.: GIC drivers - the Characteristics of Storm-time Rapid Geomagnetic Variations , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-5667, https://doi.org/10.5194/egusphere-egu2020-5667, 2020.

On August 25, 2018 the interplanetary counterpart of the August 20, 2018 Coronal Mass Ejection (CME) hit the Earth, giving rise to a strong geomagnetic storm. We present a description of the whole sequence of events from the Sun to the ground as well as a detailed analysis of the onserved effects on the Earth's environment by using a multi instrumental approach.
We studied the ICME propagation in the interplanetary space up to the analysis of its effects in the magnetosphere, ionosphere and at ground. To accomplish this task, we used ground and space collected data, including data from CSES (China Seismo Electric Satellite), launched on February 11, 2018. We found a direct connection between the ICME impact point onto the magnetopause and the pattern of the Earth's polar electrojects. Using the Tsyganenko TS04 model prevision, we were able to correctly identify the principal magnetospheric current system activating during the different phases of the geomagnetic storm. Moreover, we analyzed the space-weather effects associated with the August 25, 2018 solar event in terms of evaluation geomagnetically induced currents (GIC) and identification of possible GPS loss of lock. We found that, despite the strong geomagnetic storm, no loss of lock has been detected. On the contrary, the GIC hazard was found to be potentially more dangerous than other past, more powerful solar events, such as the St. Patrick geomagnetic storm, especially at latitudes higher than $60^\circ$ in the European sector.

How to cite: Piersanti, M., De Michelis, P., Del Moro, D., Tozzi, R., Pezzopane, M., Consolini, G., Laurenza, M., Di Matteo, S., Pignalberi, A., Quattrociocchi, V., and Diego, P.: From the Sun to the Earth: August 25, 2018 geomagnetic storm effects, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1416, https://doi.org/10.5194/egusphere-egu2020-1416, 2020.

The interaction of the solar wind with the Earth’s magnetic field produces geomagnetic activity, which is critically dependent on the orientation of the interplanetary magnetic field (IMF). Most solar wind coupling functions quantify this dependence on the IMF orientation with the so-called IMF clock angle in a way, which is symmetric with respect to the sign of the By component. However, recent studies have shown that IMF By is an additional, independent driver of high-latitude geomagnetic activity, leading to higher (weaker) geomagnetic activity in Northern Hemisphere (NH) winter for By > 0 (By < 0). For NH summer the dependence on the By sign is reversed. We quantify the size of this explicit By-effect with respect to the solar wind coupling function, both for northern and southern high-latitude geomagnetic activity. We show that for a given value of solar wind coupling function, geomagnetic activity is about 40% stronger for By > 0 than for By < 0 in NH winter. The physical mechanism of the By-effect is not yet fully understood. Here we show that IMF By modulates the flux of energetic electrons precipitating into the ionosphere which likely modulates the ionospheric conductivity and, thus, geomagnetic activity. Our results highlight the importance of the IMF By-component for space weather and must be taken into account in future space weather modeling.

How to cite: Holappa, L., Asikainen, T., and Mursula, K.: Explicit IMF By-dependence in geomagnetic activity, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3367, https://doi.org/10.5194/egusphere-egu2020-3367, 2020.

Atomic hydrogen plays a key role for the plasmasphere, exosphere, and the nighttime ionosphere. It directly impacts the rate of plasmasphere refilling after strong magnetic storms as atomic hydrogen is the primary source of hydrogen ions. It is the source of the geocorona, which significantly affects ring current decay during the recovery phase of magnetic storms.

Our previous studies with the Kharkiv incoherent scatter radar (49.6 N, 36.3 E), Arase and DMSP satellite missions, and FLIP physical model showed that during magnetically quiet periods of 2016–2018 the hydrogen density was generally a factor of 2 higher than from the NRLMSIS00-E model (Kotov et al., 2018).

Even larger values of thermospheric hydrogen density were detected prior to the severe storm of September 8, 2017. With Kharkiv IS radar, AWDANet whistler receivers, Arase satellite, and TEC data we found that during the nights of September 5 to 6 and September 6 to 7, the thermospheric hydrogen density had to be at least a factor of 4 higher than the values from NRLMSIS00-E model i.e. ~100% higher than expected from our previous studies. We discuss the possible mechanisms that could lead to the increased hydrogen density.

Such high hydrogen densities may be the reason for very quick recovery of inner plasmasphere after the severe depletion by the storm of September 8, 2017 (Obana et al., 2019).

References:

1. Kotov, D. V., Richards, P. G., Truhlík, V., Bogomaz, O. V., Shulha, M. O., Maruyama, N., et al. ( 2018). Coincident observations by the Kharkiv IS radar and ionosonde, DMSP and Arase (ERG) satellites, and FLIP model simulations: Implications for the NRLMSISE‐00 hydrogen density, plasmasphere, and ionosphere. Geophysical Research Letters, 45, 8062– 8071. https://doi.org/10.1029/2018GL079206

2. Obana, Y., Maruyama, N., Shinbori, A., Hashimoto, K. K., Fedrizzi, M., Nosé, M., et al. (2019). Response of the ionosphere‐plasmasphere coupling to the September 2017 storm: What erodes the plasmasphere so severely? Space Weather, 17, 861–876. https://doi.org/10.1029/2019SW002168

How to cite: Kotov, D., Richards, P., Bogomaz, O., Shulha, M., Maruyama, N., Fedrizzi, M., Truhlík, V., Lichtenberger, J., Hernández-Pajares, M., Miyoshi, Y., Kasahara, Y., Kumamoto, A., Tsuchiya, F., Shoji, M., Matsuoka, A., Shinohara, I., Zhivolup, T., Emelyanov, L., Chepurnyy, Y., and Domnin, I.: Unusually high thermospheric hydrogen density prior to severe storm of September 8, 2017 and its impact on the storm manifestations, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-6925, https://doi.org/10.5194/egusphere-egu2020-6925, 2020.

Extreme space weather events are extremely rare, but pose a significant threat to our infrastructure. The one known event of such kind was the Carrington storm of 1859, but it was not well documented; in particular the solar wind and IMF conditions that caused it remain guesses. On the other hand, the STEREO-A observations of July 23, 2012 showed solar wind and IMF parameters that are most likely comparable to those of the Carrington event, and remind us that such extreme events are very well possible even during times of a quiet sun. Here, we use OpenGGCM simulations of such events to assess the effects of such solar wind and IMF on the magnetosphere. Precious work has shown that during the much more benign Halloween storm the nose of the magnetopause was as close as 4.9 RE, with an accordingly large polar cap. We will present simulations of a sequence of scaled-up storms with increasingly larger driving and demonstrate the further expansion of the polar cap, intensity of plasma injections, and the eventual saturation. In addition, we will show how the ionosphere potential penetrates to lower latitudes and affects the ionosphere and thermosphere at mid latitudes when the solar wind drivers become extreme.

How to cite: Raeder, J., Tulegenov, B., Cramer, W. D., Germaschewswski, K., Ferdousi, B., Maruyama, N., and Fuller-Rowell, T.: Severe Space Weather: Simulations of Scaled-Up Storms, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10026, https://doi.org/10.5194/egusphere-egu2020-10026, 2020.

FORMOSAT-7/COSMIC-2 (F7/C2), with the mission orbit of 550 km altitude, 24-deg inclination, and a period of 97 minutes, was launched on June 25, 2019.  Tri-GNSS Radio occultation (RO) receiver System (TGRS), Ion Velocity Meter (IVM), and RF Beacon (RFB) onboard F7/C2 six small satellites allow scientists to three-dimensionally observe the plasma structure and dynamics in the mid-latitude, low-latitude, and equatorial ionosphere.  Measurements of F7/C2 RO as well as the IVM ion density, ion temperature, and ion velocity have a better understanding on mechanisms of the plasma depletion bays, non-migrating tides, and scintillations.  Moreover, observations of ionospheric F7/C2 RO electron density profiles and the total electron content derived from global ground-based GNSS receivers are used to carry out ionospheric weather monitoring, nowcast, and forecast for positioning, navigation, and communication application.

How to cite: Chang, F.-Y., Liu, J.-Y., Lin, C.-Y., Chen, S.-P., and Lin, C.: Ionospheric Weather Observations of FORMOSAT-7/COSMIC-2, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-21810, https://doi.org/10.5194/egusphere-egu2020-21810, 2020.

The International GNSS Service (IGS) has accepted for official release a new ionospheric product for specification of ionospheric irregularities occurrence and intensity over the Northern Hemisphere as derived from multi-site ground-based GPS observations. Initially, we focused on the Northern Hemisphere auroral and midlatitude regions because of the highest concentration of the GNSS users and user supporting permanent networks located within the American, European, and Asian sectors. The IGS ROTI maps product is routinely generated by multi-step processing of carrier phase delays in dual-frequency GPS signals and transferred to the IGS CDDIS database. Now, ROTI maps allow regular monitoring of ionospheric irregularities over the Northern Hemisphere and provide information about past events when strong ionospheric irregularities developed here.

Obviously, the plasma irregularities that occur at high, middle, and low latitudes have different physical mechanisms of their origin and development. For study of the climatological features of ionospheric irregularities occurrence, investigation of the ionospheric responses for Space Weather drivers, processes derived from below, this actual ROTI Map product is required to cover low latitudes and the Southern hemisphere polar and midlatitudes.

During last decade, numerous ground-based permanent receivers were deployed within the global and regional networks and these observations are publicly available. These data can support our activity toward extending the current IGS ROTI maps product for a global coverage. In this paper, we present initial results of ROTI maps product performance to characterize ionospheric irregularities exited by different types of geophysical processes and space weather events. The next generation of the IGS ROTI maps product can be a valuable tool for global ionospheric irregularities monitoring and retrospective analysis of plasma irregularities impact on the GNSS positioning in the “worst case scenario” domain.

The research is supported by the National Science Centre, Poland, through grants 2017/25/B/ST10/00479 and 2017/27/B/ST10/02190 and the National Centre for Research and Development, Poland, through grant DWM/PL-CHN/97/2019

Keywords: GPS, ionosphere, ionospheric irregularities, ROTI, IGS

How to cite: Krankowski, A., Cherniak, I., Zakharenkova, I., Fron, A., and Kotulak, K.: The next generation of IGS ROTI Maps: an extension toward global coverage, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-17905, https://doi.org/10.5194/egusphere-egu2020-17905, 2020.

In this study, we assess the hourly variations of the three-dimensional proton flux distribution inside the South Atlantic Anomaly (SAA) during a geomagnetic storm. We have developed a relativistic three-dimensional guiding center test particle simulation code in order to compute the proton trajectories in a time-varying magnetic field background provided by Tsyganenko model TS05 and the corresponding time-varying inductive electric field. The Dst index is the main input parameter to the simulation model, while the maximum proton flux, the area of the SAA calculated below a selected threshold, and the penetration depth of the protons are the main output variables investigated in this study were. Since the LEO spacecraft and human-related activities are already affected by space weather conditions, the South Atlantic Anomaly (SAA) is also believed to create an additional source of risk. As the radiation environment depends essentially on the particle flux, the objective of this study is to estimate quantitatively the proton flux variations inside the South Atlantic Anomaly (SAA) in quiet and in storm conditions. So far, it was found that after several drift periods, the protons in the South Atlantic Anomaly (SAA) could penetrate to lower altitudes during geomagnetic storm event, and that, the SAA maximum flux value and the corresponding area, varied differently with respect to altitudes. Numerical results were compared with observations by NOAA 17 and RD3R2 instrument mounted on International Space Station (ISS).

How to cite: Girgis, K., Hada, T., and Matsukiyo, S.: Space Weather Effects on Proton Flux Variations in the South Atlantic Anomaly: A Numerical Study performed by Test Particle Simulations, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1551, https://doi.org/10.5194/egusphere-egu2020-1551, 2020.

The LOFAR (Low Frequency Array) is one of the world’s leading radio telescopes, operating across the frequency band 10-250 MHz. As radio waves from astronomical sources pass through the ionosphere, they can undergo refraction and/or diffraction. The variations in the intensity of the received signal are caused by irregularities with a spatial scale size ranging from the Fresnel dimension to an order of magnitude below this value. The received signal can therefore be used to infer information on plasma structures in the ionosphere. As the frequencies used are significantly lower than the 1.4 GHz typically associated with Global Navigation Satellite Systems (GNSS), the plasma structures that affect the signals received by LOFAR are significantly larger, typically of the order of kilometres.

On 14^th July 2018 the Dutch stations of LOFAR observed the strong natural radio sources Cassiopeia A and Cygnus A between 17:00 UT and 18:05 UT at a frequency range of 20-80 MHz. During the observation, the signal intensity received by many of the stations underwent a substantial reduction across all frequencies, lasting approximately 10 minutes. Immediately before and after this, periodic enhancements in the signal strength were observed. These enhancements showed a noticeable frequency dependence, with longer period oscillations at lower frequencies. The feature was not observed simultaneously by the stations and evolved during the observations. Such a feature is most likely to be the result of a large-scale density structure in the ionosphere, which appears to move west and north over the northern Netherlands.

The deep fading of the received signal may be due to the presence of sporadic-E, which is a consequence of variations in the neutral wind speed with altitude in the presence of the geomagnetic field, resulting in plasma accumulating in a thin layer. This can cause incident radio waves to be strongly refracted, affecting the strength of the received signal. The wave-like structure immediately before and after the deep fade is a likely consequence of scattering of the observed signal.

How to cite: Wood, A., Dorrian, G., and Fallows, R.: An unusual observation of a plasma structure in the mid-latitude ionosphere, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-1562, https://doi.org/10.5194/egusphere-egu2020-1562, 2020.

Telluric currents are the natural phenomena especially pronounced in the high latitude areas (above 60 degrees). These currents, as any stray current, are able to interfere with pipeline cathodic protection systems, and came into wide consideration with construction of pipelines in northern areas, where the geomagnetic variations are more severe and last for prolonged times.

The paper will explain the approach developed for estimation of pipeline corrosion rates due to telluric activity, and results of its applications.

Statistical evaluation of the occurrence rates for the pipe-to-soil potential difference values based on modelling of the pipeline response to the geomagnetic activity in two different locations (high latitude and mid-latitude) will be combined with the method developed for calculation of corrosion rate (metal loss). The presented approach and results of its application to different types of pipelines located at different latitudes can be used as a practical guidance for the assessments of the space weather impacts on pipeline operations.

How to cite: Trichtchenko, L.: Evaluation of pipeline corrosion rates due to enhanced telluric activity associated with space weather , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-3747, https://doi.org/10.5194/egusphere-egu2020-3747, 2020.

During the solar activity cycle 24, which started at the end of 2008, Sun was behaving silently and there were not many spectacular geoeffective events. Here we analyze the geomagnetic storm which happened on July 15 of 2012 in the 602 anniversary of the famous Polish Battle of Grunwald. According to the NOAA scale, it was G3 geomagnetic storm with Bz heliospheric magnetic field component dropping up to -20 nT, Dst index below -130 nT, AE index greater than 1300 nT and ap index being above 130 nT. It was proceeded by the solar flare of X1.4 class on 12 of July. This geomagnetic storm was accompanied by the fast halo coronal mass ejection 16:48:05 on 12 of July-the first C2 appearance, with the apparent speed 885 km/s and space speed 1405 km/s. This geomagnetic storm was classified as the fourth of the strongest geomagnetic storms from SC 24. Around that time in Polish electric transmission lines infrastructure, there was observed a significant growth of the number of failures that might be of solar origin.

Acknowledgments: the Polish National Science Centre, grant number 2016/22/E/HS5/00406.

How to cite: Gil, A., Modzelewska, R., Moskwa, S., Siluszyk, A., Siluszyk, M., and Wawrzynczak, A.: Geoeffectiveness of the ‘Battle of Grunwald day’ in 2012, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-8326, https://doi.org/10.5194/egusphere-egu2020-8326, 2020.

How to cite: Matyjasiak, B., Przepiórka, D., and Rothkaehl, H.: Influence of seasonal changes on the mid-latitude trough properties, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-8427, https://doi.org/10.5194/egusphere-egu2020-8427, 2020.

Electron density in ionospheric plasma exhibits fluctuations and irregularities in time and space, at several scales. Plasma, being ionized gas, is subject to a turbulent behaviour similar to that observed in fluid dynamics, with two main distinctions: a) its dynamics are coupled with electromagnetic fields; b) collisions of particles are rare. These unique properties characterize the inertial range of ionospheric plasma turbulence, which represents the energy cascade from large-scale structures (e.g. travelling ionospheric disturbances) to small-scale ones (eddies) until energy dissipation occurs. 

Kolmogorov power law would predict a spectrum of 8/3 and equivalently a structure function with a power law of 5/3 for a phase signal crossing a 3D turbulent medium. However, the previous investigation of spatial structure characteristic of the ionosphere using LOFAR array observed a power law of around 1.9 in the spatial domain. In this study, we investigate the spatio-temporal and temporal structure of the ionosphere using structure function of GNSS phase geometry free signals from both medium earth orbit satellites and geostationary ones. We found two regimes, one compatible the 5/3 Kolmogorov theory and one obeying a 2 power law. We propose an interpretation for the two regimes, the first being a 3D turbulent flow driven by local instabilities, and the second one being driven by solar radiation-induced ionization and successive recombination. The second spectrum obeys a power law of 2, that is the power spectrum of a sinusoidal function like the local sun elevation. By using receivers at almost constant solar irradiance located in polar regions, we further observe the turbulent regimes also in spatio-temporal structure function.

How to cite: Tagliaferro, G., Gatti, A., and Realini, E.: Sensing Ionospheric Turbulence Using GNSS, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-8604, https://doi.org/10.5194/egusphere-egu2020-8604, 2020.

The Board Telescope of Neutrons (BTN) is a neutron spectrometer which was installed outside of the Russian “Zvezda” module of the International Space Station (ISS) in November 2006. The main goals of this experiment include measurement of neutron flux in broad energy band from low epithermal neutrons (>0.4 eV) up to fast neutrons (<15 MeV); investigation of its spatial variations at low and high geomagnetic latitudes above the South Atlantic anomaly (SAA) and at different orbital altitudes; observations of  GCR variations on different time scales from orbital fluctuations to variations affected by the 11-year solar cycle; estimation of the neutron component of radiation background outside ISS during various flight conditions in near-Earth orbit.

In this study we present measurements of neutron-flux spectral density in the vicinity of the International Space Station (ISS) based on BTN-Neutron space experimental data for the period 2007-2019. Neutron flux shows space and time variations. It varies by several orders of magnitude between equatorial latitudes and flybys across South Atlantic anomaly region. The time profile of neutron flux also demonstrates long-periodic variations produced by variations of GCRs and modulated by 11 year solar cycle. The observed amplitude of such variations is about two times. We have compared it with other space neutron monitors installed on Moon (NASA/LRO), Mars (NASA/Odyssey, ESA/ExoMars)and Mercury (ESA/BepiColombo) missions.   

We also used neutron measurements to evaluate biological impact contributed by neutrons and expressed in neutron equivalent dose rate.  

How to cite: Litvak, M., Golovin, D., Kozyrev, A., Mitrofanov, I., and Sanin, A.: Long-term monitoring of neutron component of radiation background onboard International Space Station., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-9763, https://doi.org/10.5194/egusphere-egu2020-9763, 2020.

A lot of information has been accumulated recently demonstrating impacts of solar activity on the Earth’s seismicity. We observe the transition from correlation-driven papers to the more physical based works. The effects of solar influence could be separated by agents of energy transfer which could be electromagnetic emission of the Sun, particle fluxes of solar wind, solar proton events, modification of radiation belts and indirect impacts through the intermediate agent, such as atmosphere disturbances and modification of atmosphere circulation as effect of solar activity. Effects of the galactic cosmic rays should be taken into account including the Forbush decreases, which are result of geomagnetic storms. MHD electromagnetic sounding stimulating the earthquake activity could be considered as a physical model of the geomagnetic storms effect on the seismic activity.

The most intriguing effects discovered recently is the inducing the strong M>7 earthquakes by the precipitation from additional radiation belt at L-shell 1.5-1.8 formed after the strong geomagnetic storm. Precipitation of relativistic particles from this shell induces the strong earthquakes with delay nearly 2 months.

One very importing agent of geosphere coupling including the energy transfer int the lithosphere is the Global Electric Circuite.

It is difficult to explain the observed phenomena by simple transformation of solar energy into mechanical deformation, it seems that more plausible explanation is the pumping of energy into the Earth’s crust volume being in a metastable state.

This work was supported by the Ministry of Education and Science of the Russian Federation in accordance with Subsidy Agreement No. 05.585.21.0008. The unique identifier is RFMEFI58519X0008

How to cite: Pulinets, S. and Khachikyan, G.: Solar induced earthquakes – review and new results, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-10821, https://doi.org/10.5194/egusphere-egu2020-10821, 2020.

The global electric circuit (GEC) links the electric field and current flowing in the lower atmosphere, ionosphere and magnetosphere forming a giant spherical condenser, which is charged by the thunderstorms to a potential of several hundred thousand volts (Roble and Tzur, 1986) and drives vertical current through the atmosphere’s columnar resistance. Monitoring and researching the global electric circuit (GEC) are crucially important due to its links with climate change. Those two phenomena are connected by lightning activity, which itself is a measure of the GEC. It is known that space weather affects the Earth’s lightning activity, therefore the GEC might prove to be a critical tool in examining changing climate in terms of solar and lightning activity.

The possible relation between solar activity and lightning activity has been studied for a long period of time. The relation between sunspot number and lightning activity has been investigated, although the results still remain inconclusive across regions and time. At some regions a positive correlation is found, at others a negative one. Thus, it is important to explore other solar-geomagnetic variables possibly influencing lightning activity, such as geomagnetic index or fast solar wind streams, which were found to correlate well with lightning activity (Scott et al, 2014). Another increasingly important question is whether or not aerosols will contribute significantly to the Earth’s radiation budget, whether it be cooling or warming the climate. In a warming climate aerosol loading could alter and increase lightning activity, which in turn can lead to a positive feedback due to generation of NOx and thus O3 in the troposphere, a potent greenhouse gas.

In this project we will look at the connection between solar activity, aerosol loading, and thunderstorm activity in different types of regions such as coastal, boreal forest and urban area first in Finland and later on globally.

1. Aniol, R., 1952. Schwankungen der Gewitterha

How to cite: Khansari, M., Tanskanen, E., and Nikbakhsh, S.: The effects of solar activity on the Global Atmospheric Electrical Circuit , EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12964, https://doi.org/10.5194/egusphere-egu2020-12964, 2020.

The world relies increasingly on capabilities that are enabled or delivered by space-based systems, and there exists a need to continually refine our vulnerability assessment models and understanding of natural versus artificial threats. One area of growing global focus is monitoring and mitigating hazards for space-based systems that are highly dependent on the space atmospheric environment. For example, in 2018 the United States defined benchmarks for five space weather phenomena critical to vulnerability assessment for national infrastructure and services, and for stakeholder mitigation planning. We were invited to lead the next-phase national working group in benchmarking of ionospheric disturbances to capture physical properties of the medium and response to solar drivers; key parameters include ionospheric electron content, turbulence, and absorption that characterize the medium for radio propagation. All such values translate readily into impacts on existing and emerging technologies for users/operators.

In this context we present new methods of ionospheric characterization and parameterization to gain insight into the impact on ground- and space-based RF systems. Our approach exploits the University of Calgary Transition Region Explorer (TREx) network for geospace sensing – a federal investment in over 40 sophisticated optical, magnetic and radio instruments across Canada. Combined with our modeling tools, this is one of the world’s foremost high latitude facilities for remote sensing of the near-earth space environment. On track to be fully operational in 2020, our ground-based infrastructure includes new technologies in auroral cameras and imaging riometers. At distributed key locations within the target region, multi-constellation Global Navigation Satellite System (GNSS) total electron content (TEC)/scintillation receivers and commercial grade systems also provide multi-scale scientific observations.

We present space weather monitoring for ground-based and space-based RF systems. Our ionosphere modeling capabilities include a data driven approach to estimate the three-dimensional temporally evolving electron density distributions over regional spatial scales. Input observations can include integrated TEC for multi-constellation GNSS signals from ground-based receivers, topside over-satellite TEC from space-borne GNSS receivers (e.g. Swarm), and GNSS occulting link TEC from low-earth orbiters. We also exploit small-scale Swarm in situ plasma density observations to estimate ionospheric turbulence. We focus on two recent studies:

1) The assimilation of imaging riometer observations to provide D-region specification and estimation of key space weather parameters for HF applications.

2) Ionospheric scintillation modeling based on turbulence key parameters for transionospheric RF signal propagation and related applications such as GNSS.

Outcomes include new approaches in space situational awareness and monitoring of space environmental conditions with improved anomaly resolution (distinguishing artificial from natural hazards) and informed mitigation.

How to cite: Skone, S., Najmafshar, M., and Bust, G.: Characterizing Ionospheric Disturbances for Space Weather Hazard Mitigation, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-12999, https://doi.org/10.5194/egusphere-egu2020-12999, 2020.

The Low Frequency Array (LOFAR) is an advanced phased-array radio-telescope system based across Europe.  It is capable of observing over a wide radio bandwidth of ~10-250 MHz at both high spatial and temporal resolutions.  LOFAR has capabilities that enable studies of many aspects of what we class as space weather (from the Sun to the Earth and afar) to be progressed beyond today’s state-of-the-art.   However, with the present setup and organisation behind the operations of the telescope, it can only be used for space-weather campaign studies with limited triggering availability.  This severely limits our ability to effectively use LOFAR to contribute to space-weather monitoring/forecast beyond its core strength of enabling world-leading scientific research.  LOFAR itself is made up of a dense core of 24 stations near Exloo in The Netherlands with an additional 14 stations spread across the northeast Netherlands.  In addition to those, there are a further 13 stations based internationally across Europe.  These international stations are, currently, six in Germany, three in northern Poland, and one each in France, Ireland, Latvia, Sweden, and the UK.  Further sites are under preparations (for example, in Italy).

We are undertaking a Horizon 2020 (H2020) INFRADEV design study to undertake investigations into upgrading LOFAR to allow for regular space-weather science/monitoring observations in parallel with normal radio-astronomy/scientific operations.  This project is called the LOFAR For Space Weather (LOFAR4SW) project (see: http://lofar4sw.eu/).  Our work involves all aspects of scientific and engineering work along with end-user and political engagements with various stakeholders.  This is with the full recognition that space weather is a worldwide threat with varying local, regional, continent-wide impacts, and also global impacts – and hence is a global concern.

Here, we summarise the most-recent key aspects of the LOFAR4SW progress including outputs/progress following the Detailed Design Review (DDR) that took place at ASTRON, The Netherlands, in March 2020, as well as the implementation of recommendations from the earlier Preliminary Design Review (PDR) with an outlook to the LOFAR4SW User Workshop the week following EGU 2020.  We also aim to briefly summarise a key set of the longer-term goals envisaged for LOFAR to become one of Europe’s most-comprehensive space-weather observing systems capable of shedding new light on several aspects of the space-weather system, from the Sun to the solar wind to Jupiter and Earth’s ionosphere.

How to cite: Bisi, M. M., Ruiter, M., Fallows, R. A., Vermeulen, R., Robertson, S. C., Vilmer, N., Rothkaehl, H., Matyjasiak, B., Verbiest, J., Gallagher, P. T., Olberg, M., Carozzi, T., Lindqvist, M., Carley, E., Krüger, P., Mevius, M., Baldovin, C., and Barnes, D.: LOFAR4SpaceWeather (LOFAR4SW) – Increasing European Space-Weather Capability with Europe’s Largest Radio Telescope: Beyond the Detailed Design Review (DDR), EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-14948, https://doi.org/10.5194/egusphere-egu2020-14948, 2020.

How to cite: Przepiórka, D., Matyjasiak, B., and Rothkaehl, H.: Solar activity and its impact on the mid-latitude trough during geomagnetic storms, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18228, https://doi.org/10.5194/egusphere-egu2020-18228, 2020.

How to cite: Pożoga, M., Grzesiak, M., Matyjasiak, B., Rothkaehl, H., Wronowski, R., Budzińska, K., and Tomasik, Ł.: Ionospheric scintillation indexes for LOFAR single station observation mode, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18287, https://doi.org/10.5194/egusphere-egu2020-18287, 2020.

The Earth’s auroral region and its close neighbourhood is the origin of strong radio emissions caused by complex physical plasma processes. Among them we can list auroral hiss, auroral roar, auroral medium frequency (MF) burst, and auroral kilometric radiation (AKR).  Analysis of such emissions can provide information about magnetospheric structure and dynamics. 

In this work we present selected cases of Earth’s AKR-like radio emissions observed by RELEC  and mission at the top side ionosphere leyers. The emissions are seen at frequencies of the order of hundreds of kHz in the ionosphere, just below the auroral oval and  can be observed not only in disturbed geomagnetic conditions, but also during quiet periods. The maximum occurrence is at ∼ 75 ◦ invariant latitude and can have extent up to ∼ 11 ◦ in invariant latitude.

How to cite: Rothkaehl, H., Matyjasiak, B., Chuchra, A., Schreiber, R., Marek, M., and Przepiórka, D.: High frequency radio emissions as a manifestation of physical processes in the auroral plasma, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18465, https://doi.org/10.5194/egusphere-egu2020-18465, 2020.

How to cite: Atamaniuk, B., Krasheninnikov, I. V., Popov, A., and Matyjasiak, B.: Problem ot the energy transfer for radio paths near single-hop limiting distance for low solar activity, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18481, https://doi.org/10.5194/egusphere-egu2020-18481, 2020.

How to cite: Budzińska, K., Mevius, M., Grzesiak, M., Pożoga, M., Matyjasiak, B., and Rothkaehl, H.: Direction of ionospheric structures in LOFAR calibration data, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18597, https://doi.org/10.5194/egusphere-egu2020-18597, 2020.

In January 2019 the new Super Dual Auroral Radar Network (SuperDARN) radar installed at the Concordia Station in Antarctica and denominated Dome C North (DCN) saw the first light. SuperDARN is an international network of HF radars that observe the effects produced in the ionosphere by the chain of phenomena taking place in the Earth's space environment. DCN and its companion radar Dome C East (DCE) are positioned nearby the southern geomagnetic pole with their Field of View extending towards the auroral latitudes. Here we present the analysis of the first year of observations as a function of the interplanetary conditions.

How to cite: Marcucci, M. F., Coco, I., Massetti, S., Longo, S., Biondi, D., Simeoli, E., Cirioni, A., Satta, A., De Simone, A., and Marchaudon, A.: Dome C North radar, a new radar of the SuperDARN network: the first year of observations., EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-18662, https://doi.org/10.5194/egusphere-egu2020-18662, 2020.

The strongest event of geomagnetically induced currents (GIC) detected by the North-West Russian GIC network occurred during the main phase of the magnetic storm on June 28-29, 2013. Extremely high values, 120 A, were recorded in the 330 kV transformers on Kola Peninsula in the 04--07 magnetic local time (MLT) sector. The Defense Meteorological Satellite Program (DMSP) spacecraft took a sequence of ultraviolet (UV) auroral images in the southern hemisphere and observed multiple omega bands. The ionospheric equivalent electric currents based on the International Monitor for Auroral Geomagnetic Effects (IMAGE) magnetometer network reveal a sequence of current vortex pairs moving eastward with the speed of 0.5-2.5 km/s, that fits to the electrodynamics scheme of omega bands. Although the temporal variations of the associated current system are slow, the omega bands can be responsible for strong magnetic variations and GIC due to fast propagations of currents in the azimuthal direction.  The first steps towards the statistica study of the highest GIC recorded at Vykhodnoy transformer show that about 50% of events have properties similar to the comprehensively studied 29 June 2013 case.

How to cite: Apatenkov, S., Pilipenko, V., Gordeev, E., Viljanen, A., Juusola, L., Belakhovsky, V., Sakharov, Y., and Selivanov, V.: Auroral omega bands are a significant cause of large geomagnetically induced currents, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-19755, https://doi.org/10.5194/egusphere-egu2020-19755, 2020.

For the UK, the potential impacts from severe space weather (and everyday space weather) are considered of a high importance and hence the UK Government has included “Severe Space Weather” on its National Risk Register of Civil Emergencies since 2011.  This is not just considering direct impacts on UK infrastructures, but also impacts to key partner/trading/neighbouring nations.  This has led to a long series of national and international engagements and strategic developments both between UK agencies/entities and with international agencies/organisations (such as ESA, NOAA, NASA, COSPAR, ISES, ICAO, WMO, and UN COPUOS).  On top of this, the UK has undertaken a series of wide-ranging investigations to mitigate space-weather impacts at the national level including the ongoing development of a national Space Weather Strategy – where the UK looks to experts across all sectors to feed into its development.

An essential aspect of trying to mitigate space-weather impacts on the UK is the need for independent UK space-weather forecast capability in collaboration with the other 24/7 space-weather forecasting institutes around the World.  This UK capability allows for direct advice to government on all things space weather, particularly on what to do when an impending event is expected and throughout its duration and recovery.  Hence, he setting up of a UK staffed 24/7 space-weather forecasting centre at the Met Office alongside the formation of the Space Environment Impacts Expert Group (SEIEG) of experts were undertaken to provide the necessary advice to government.

The UK is currently committing a large amount of money both to dedicated UK-based and ESA-based space weather programmes as well as through traditional science research funding channels.  This includes the UKRI Strategic Priorities Fund (SPF) Space Weather Instrumentation, Measurement, Modelling and Risk (SWIMMR) programme and the ESA Space Safety Programme.  The UK has also taken a lead on several other space-/ground-based space-weather endeavours that are proving highly complementary to current UK and global capabilities.

In this presentation, we will provide an overview of the above along with any outline of the UK Space Weather Strategy open to the public at the time of the EGU 2020 Meeting.

How to cite: Bisi, M. M., Gibbs, M., Hapgood, M. A., Willis, M., Harrison, R. A., Machin, S., and McCrea, I. W.: Space Weather in the UK: Updates on the UK Strategy, Investment, and International Engagements, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-22231, https://doi.org/10.5194/egusphere-egu2020-22231, 2020.