Session - Monitoring, Modelling and Predicting Space Radio Weather

M. Messerotti, V. Pierrard, S. Pohjolainen

Space radio weather refers to the physical state of the Heliosphere, i.e. the Sun, the Interplanetary Medium, the planetary magnetospheres and atmospheres, as observed in the radio domain of the electromagnetic spectrum. Radio emissions from plasmas are originated by a large variety of nonlinear processes that operate at different physical conditions and involve particle and wave interactions. Furthermore, magnetic fields play a significant role in both the generation and the propagation of radio waves. Hence, monitoring and modelling the radio signatures of plasma processes constitute powerful diagnostic means to identify the triggering phenomenon and the plasma state at the source as well as the plasma characteristics along the propagation path. A complex zoo of radio emissions has been observed in the different environments, e.g. electron beams are accelerated in solar flares and their radio signatures are solar type III radio bursts, propagating hydrodynamic shocks in the solar corona can originate solar type II radio bursts, and electron beams accelerated by CME shock fronts are associated with interplanetary type III radio bursts. Radio emissions also characterise processes occurring in planetary magnetospheres and ionospheres. Furthermore, solar radio emissions can impact on radio communications as increased background noise can severely affect GNSS localisation in the whole sunlit hemisphere. Hence, monitoring, modelling and predicting radio emissions are key operational components for any consolidated Space Weather workflow.

Authors are invited to submit abstracts dealing with one or more of the following topics focussed on Space Weather applications:

- Monitoring techniques and instruments for radio signatures;
- Models of radio emission processes and propagation effects;
- Prediction techniques using radio emission.

Talks
Thursday November 26, 11:00 - 13:00, Leopold

Poster Viewing
Thursday November 26, 10:00 - 11:00, Poster area

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Talks : Time schedule

Thursday November 26, 11:00 - 13:00, Leopold

11:00	Status and Prospects for Solar Radio Burst Monitoring	Gallagher, P et al.	Invited Oral
	Peter T Gallagher
	Trinity College Dublin, Dublin 2, Ireland
	Solar radio bursts can have adverse effects on a variety of ground- and space-based systems used in communications and navigation systems. At microwave frequencies, radio bursts can cause increases in dropped-call rates on mobile phone networks and decrease the performance of GNSS/GPS systems, while VHF and HF communication systems can be interrupted as a result of solar variability at low frequencies. It is therefore necessary to monitor the radio Sun across the frequencies used in these technological systems. There are a number of space-weather dedicated solar radio burst monitoring systems operated by the US, Korean and Australia for example. In addition, there are radio instruments at locations in the US, European and Asia that monitor solar radio bursts for scientific purposes. Despite the availability of these instruments, no single system offers users uninterrupted solar radio burst monitoring across a wide range of frequencies relevant to technological systems. Here, I will review our solar radio monitoring capabilities and discuss prospects for the development of radio instruments and networks to monitor solar radio bursts and associated space weather effects.
11:20	Plasmaspheric electron densities and plasmasphere models for space weather investigations	Lichtenberger, J et al.	Oral
	János Lichtenberger[1,2], Anders Jorgensen[3], David Koronczay[1,2], Lilla Juhász[1], Csaba Ferencz[1], Dániel Hamar[1], Péter Steinbach[4], Mark Clilverd[5], Craig Rodger[6],   Dmitry Sannikov[7] and Nina Cherneva[7]
	[1] Department of Geophysics and Space Sciences, Eötvös University, Budapest, Hungary; [2] Geodetic and Geophysical Institute, RCAES, Sopron, Hungary; [3] Research Group for Geology, Geophysics and Space Sciences, HAS, Budapest, Hungary; [4] Electrical Engineering Department, New Mexico Institute of Mining and Technology, Socorro, USA; [5] British Antarctic Survey, Cambridge, United Kingdom; [6] Department of Physics, University of Otago, Dunedin, New Zealand; [7] Institute of Cosmophysical Research and Radio Wave Propagation, Paratunka, Russia
	The Automatic Whistler Detector and Analyzer Network (AWDANet, Lichtenberger et al., J. Geophys. Res., 113, 2008, A12201, doi:10.1029/2008JA013467) is able to detect and analyze whistlers in quasi-realtime and can provide equatorial electron density data. The plasmaspheric electron densities are key parameters for plasmasphere models in Space Weather related investigations, particularly in modeling charged particle accelerations and losses in Radiation Belts. The global AWDANet detects millions of whistlers in a year. The network operates since eraly 2002 with automatic whistler detector capability and it has been recently completed with automatic analyzer capability in PLASMON (http://plasmon.elte.hu, Lichtenberger et al., Space Weather Space Clim. 3 2013, A23 DOI: 10.1051/swsc/2013045.) Eu FP7-Space project. It is based on a recently developed whistler inversion model (Lichtenberger, J. J. Geophys. Res., 114, 2009, A07222, doi:10.1029/2008JA013799), that opened the way for an automated process of whistler analysis, not only for single whistler events but for complex analysis of multiple-path propagation whistler groups. The network operates in quasi real-time mode since mid-2014, fifteen stations provide equatorial electron densities that are used as inputs for a data assimilative plasmasphere model but they can also be used directly in space weather research and models. We have started to process the archive data collected by AWDANet stations since 2002 and in this paper we present the results of quasi-real-time and off-line runs processing whistlers from quiet and disturb periods. The equatorial electron densities obtained by whistler inversion are fed into the assimilative model of the plasmasphere providing a global view of the region for processed the periods.
11:30	BRAMS : a radio network using forward scatter to monitor meteoroid activity	Lamy, H et al.	Invited Oral
	Hervé Lamy[1], Sylvain Ranvier[1], Stijn Calders[1], Emmanuel Gamby[1], Michel Anciaux[1], Antonio Martinez Picar[2], Cédric Tétard[1], J. De Keyser[1]
	[1] Belgian Institute for Space Aeronomy; [2] Royal Observatory of Belgium
	BRAMS (Belgian RAdio Meteor Stations) is a Belgian network of radio receiving stations using forward scattering of radio waves on meteor ionization trails to detect and characterize the meteoroids falling in Earth’s atmosphere above Belgium. The network comprises one dedicated transmitter located in Dourbes and around 30 receiving stations spread all over the Belgian territory. The BRAMS network will be described in detail including calibration aspects. Since each BRAMS station typically records between 1500 and 2000 meteor echoes per day, an automatic detection algorithm is mandatory. Several techniques will be presented as well as their evaluation (number of false positives/negatives) using a set of data for which manual counts are available. Finally, preliminary results from the METRO project to retrieve trajectories from multi-stations observations and to study ionization in different points of the meteor trail will be briefly discussed. METRO (MEteoroids TRajectories and Origins) is is a BRAIN-be networking project funded by the Belgian Scientific Policy.
11:50	Correction’s method of the electron density model in ionosphere by ray tracing techniques	Settimi, A et al.	Oral
	Alessandro Settimi[1], Michael Pezzopane[1], Marco Pietrella[1], Carlo Scotto[1], Silvio Bianchi[2], James A. Baskaradas[3]
	[1] Istituto Nazionale di Geofisica e Vulcanologia (INGV), Sezione di Geomagnetismo, Aeronomia e Geofisica Ambientale (ROMA 2), Via di Vigna Murata 605, I-00143 Rome, Italy; [2] Università Sapienza, Dipartimento di Fisica, p.le Aldo Moro 2, I-00185 Rome, Italy; [3] School of Electrical & Electronics Engineering, Shanmugha Arts, Science, Technology & Research Academy (SASTRA) University, Tirumalaisamudram, Thanjavur, 613 401 Tamilnadu, India
	When applying the ray tracing in ionospheric propagation, the electron density modelling is the main input of the algorithm, since phase refractive index strongly depends on it. Also the magnetic field and frequency collision modelling have their importance, the former as responsible for the azimuth angle deviation of the vertical plane containing the radio wave, the latter for the evaluation of the absorption of the wave. Anyway, the electron density distribution is strongly dominant when one wants to evaluate the group delay time characterizing the ionospheric propagation. From the group delay time, azimuth and elevation angles it is possible to determine the point of arrival of the radio wave when it reaches the Earth surface. Moreover, the procedure to establish the target (T) position is one of the essential steps in the Over The Horizon Radar (OTHR) techniques which require the correct knowledge of the electron density distribution. The group delay time generally gives rough information of the ground range, which depends on the exact path of the radio wave in the ionosphere. This paper focuses on the lead role that is played by the variation of the electron density grid into the ray tracing algorithm, which is correlated to the change of the electron content along the ionospheric ray path, for obtaining a ray tracing as much reliable as possible. In many cases of practical interest, the group delay time depends on the geometric length and the electron content of the ray path. The issue is faced theoretically, and a simple analytical relation, between the variation of the electron content along the path and the difference in time between the group delays, calculated and measured, both in the ionosphere and in the vacuum, is obtained and discussed. An example of how an oblique radio link can be improved by varying the electron density grid is also shown and discussed.
12:00	Low Frequency Type II Radio Bursts as a Space Weather Tool	Gopalswamy, N et al.	Invited Oral
	Nat Gopalswamy
	NASA Goddard Space Flight Center
	Radio bursts type II are produced by nonthermal electrons energized by CME-driven shocks in the corona and interplanetary medium. Type II bursts at frequencies below the ionospheric cutoff are indicative of powerful shocks that travel far into the interplanetary medium as space weather events. The same shocks that produce the type II bursts also accelerate ions that constitute an important source of particle radiation with wide ranging implications to space technology, Earth’s radiation belt, ionosphere, and atmospheric ozone. The shocks are also recognized as sudden impulses delivered to Earth’s magnetosphere as leading indicators of impending geomagnetic storms. The simple fact that type II radio bursts are electromagnetic waves that travel in about 8 minutes from the Sun provide advanced warning of space weather events from minutes (particle radiation) to days ahead of their arrival at Earth. For example, an intense type II radio burst associated with a CME originating close to the disk center is a good indicator of an energetic storm particle event occurring at Earth in the next day to a couple of days. The purpose of this paper is to show that the observed properties of type II radio bursts such as the frequency drift rate in the radio dynamic spectrum can be used to predict the arrival time of CME-driven shocks with reasonable accuracy. In addition, potential deviations from the simple behavior of shock propagation that affect forecasting capability will be discussed. Illustrative examples will be shown that combine radio dynamic spectra from the WAVES experiment on board the Wind spacecraft and the coronal imagery from the Solar and Heliospheric Observatory (SOHO).
12:20	Radio triangulation of the radio signatures of a CME-CME interaction	Magdalenic, J et al.	Oral
	Jasmina Magdalenic[1], Manuela Temmer[2], Vratislav Krupar[3], Christophe Marque[1], Astrid Veronig[2], Bojan Vrsnak[4]
	[1] Royal Observatory of Belgium, Brussels, Belgium; [2] IGAM, Institute of Physics, Graz, Austria; [3] Institute of Atmospheric Physics ASCR, Prague, Czech Republic; [4] Faculty of Geodesy, Hvar Observatory, Zagreb, Croatia
	We present a study of the radio emission associated with the complex interaction of two coronal mass ejections (CMEs), successively launched from the same active region (NOAA AR 11158), on February 14 and February 15, 2011. Although this CME-CME interaction event was widely studied (e.g. Temmer et al., 2014, Maricic et al., 2014, Mishra & Srivastava, 2014) none of the analyses determined the origin of the associated continuum-like radio emission observed in the decameter-to-hectometer frequency range. The continuum-like emission patch has a particular morphology and might be considered either as a continuation of the decametric type II radio emission associated with the second CME, either as a continuation of the type III radio bursts associated with a flare from NOAA AR 11158. This ambiguity additionally complicates the question on the possible origin of the continuum-like emission. The association of this type of continuum-like radio emission and the CME-CME interaction was up to now established only by their temporal coincidence (Gopalswamy et al., 2001), which is not applicable in this event due to a complex and long-lasting interaction of the CMEs. In this work, we make us of a radio triangulation technique presented by Magdalenic et al., (2014) to obtain the 3D source positions of the continuum-like emission. Comparing the location of this radio emission, with the positions of the structures of the interacting CMEs, brings important information on the possible origin of the continuum-like emission. The first results indicate that the continuum-like radio emission might be a consequence of the interaction between the shock driven by the second CME and the streamer-like, post-eruption current sheet formed behind the first CME, as suggested by Temmer et al., (2014).
12:30	F10.7 and Space Weather	Tapping, K et al.	Invited Oral
	Kenneth Tapping
	National Research Council
	Space weather is like terrestrial weather; it comprises phenomena varying widely in amplitude and time-scale, and with a wide range of different characteristics. Since space weather is driven by the Sun, we need comprehensive programmes of solar monitoring to detect the origins of space weather events. Some monitoring programmes are essentially “event spotters”; others provide longer-term, consistent records of solar behaviour. The 10.7cm solar radio flux (F10.7) is one such index. In this presentation we will discuss the F10.7 index, its advantages and limitations, and some of its space weather applications. We will also discuss the Next Generation Solar Flux Monitor, and why we need one.
12:50	Narrow-band Bursts of Decameter Radio Emission From the Solar Corona	Voitenko, Y et al.	Oral
	Yuriy Voitenko[1], Valentin Melnik[2], Viviane Pierrard[1], Anatoly Brazhenko[3], Anatoly Frantsuzenko[3]
	[1] Belgian Institute for Space Aeronomy, Brussels, Belgium; [2] Institute of Radio Astronomy of NASU, Kharkiv, Ukraine; [3] Gravimetrical Observatory of NASU, Poltava, Ukraine
	We discuss a new kind of radio bursts at 15-33 MHz observed by UTR-2 (Kharkiv, Ukraine) and URAN-2 (Poltava, Ukraine), the world-largest radio telescopes in this frequency range. We call them type 3/2 bursts because they usually appear between type III and type II bursts. The type 3/2 bursts are narrow-band and their frequency drifts vary in the range between 50 and 170 kHz/s. Such drift rates imply emission sources propagating with velocities close to the local Alfven velocities. Our analysis suggest that the type 3/2 bursts are regulated by kinetic Alfven waves (KAWs). Parallel electric fields and plasma density fluctuations are two basic properties of KAWs coupling them with these bursts. The wave and plasma characteristics deduced from observed burst parameters are compatible with those deduced from other coronal observations. We conclude that observations and analysis of the type 3/2 bursts provide a promising tool for studying coronal processes and remote coronal diagnostics.

Posters

Thursday November 26, 10:00 - 11:00, Poster area

1	The Saint Patrick geomagnetic storm monitored by the ERICA project	Alfonsi, L et al.	e-Poster
	Gabriella Povero[1], Prayitno Abadi[2], Lucilla Alfonsi[3], Domenico Di Mauro[3], Fabio Dovis[4], Vin La The[5], Minh Le Huy[6], Marco Pini[1], Rodrigo Romero[4], Luca Spogli[3], Nicolas Floury[7]
	[1] Istituto Superiore Mario Boella (Italy); [2] LAPAN (Indonesia); [3] Istituto Nazionale di Geofisica e Vulcanologia (Italy); [4] Politecnico di Torino (Italy); [5] HUST (Vietnam); [6] IGP-VAST (Vietnam), [7] ESA
	ERICA (EquatoRial Ionosphere Characterization in Asia) is a project funded by ESA within the Alcantara Study Programme, aiming to monitor the ionosphere in the Southeast Asian region to characterize the local features of the Equatorial Ionospheric Anomaly (EIA). The characterization is based on ad hoc campaign of geomagnetic and ionospheric measurements carried out through the use of ground based professional GNSS receivers, ionosondes and magnetometers, operated by the Indonesian National Institute of Aeronautics and Space, LAPAN, the Vietnam Academy of Science and Technology, VAST and Hanoi University of Science Technology, HUST. The campaign also includes the co-location of a software receiver to provide additional information not usually accessible from professional receivers. Such further input will support a complementary reliable analysis and study of the regional ionosphere. The campaign started on March, 2015 and will finish on September 2015. The expertise of Istituto Superiore Mario Boella (ISMB, ERICA coordinator) and of Politecnico di Torino in GNSS signal processing and algorithms, together with the competences on ionospheric and geomagnetic monitoring and study, owned by Istituto Nazionale di Geofisica e Vulcanologia (INGV), are enabling a regional assessment of the ionospheric corruption on the GNSS signals propagation over South Eastern Asia. Preliminary results obtained from the analysis of the data acquired along the first month of the campaign, with particular reference to the severe geomagnetic storm occurred on March, the 17th, show clear signatures of suppression and enhancement of post-sunset scintillation during the main and the recovery phases of the storm. The network of instruments included in the ERICA campaign allowed monitoring and studying the scintillation inhibition over both the crests of EIA and of the dip equator. The results are presented and discussed in the frame of the efforts addressed to understand the ionospheric threats to GNSS-based operations in the equatorial regions.
2	Short-term Coronal Mass Ejections’ Prediction Technique Using Solar Radio Emission	Sheyner, O et al.	e-Poster
	Olga Sheyner, Vladimir Fridman
	Radiophysical Research Institute
	It is generally accepted the concept of general approach to solar Coronal Mass Ejections (CMEs): they are global phenomenon of solar activity caused by the global magnetohydrodynamic processes. These processes occur in different ranges of emission, primarily in the optical and the microwave emission being generated near the surface of the sun from a total of several thousand kilometers. The usage of radio-astronomical data for CMEs prediction is convenient and prospectively. It is so, because, the majority of the proceeding processes, as a rule, is reflected in the radio emission; spectral measurements cover all heights of solar atmosphere, sensitivity and accuracy of measurements make it possible to record even small energy changes. Registration of the radio emission is provided by virtually all-weather ground-based observations, and there is the relative cheapness to obtain the corresponding information due to a developed system of monitoring observations. On large statistical material there are established regularities of the existence of sporadic radio emission at the initial stage of CMEs’ formation and propagation in the lower layers of the solar atmosphere during the time interval from 2-3 days to 2 hours before CMEs registration on coronagraph. In this report we present the prediction algorithm and scheme of short-term forecasting developed on the base of “isolated” solar coronal mass ejections observed in 1998, 2003, 2009–2013, and statistical regularities of solar radio emission data.
3	Solar microwave bursts as disturbances of GNSS communications	Klein, K et al.	p-Poster
	Meriem Imache, Karl-Ludwig Klein
	Observatoire de Paris
	Radio bursts were occasionally strong enough to affect the signal-to-noise ratio of GPS signals. We present a study of the radio spectra of these events, using single-frequency observations including 1.4 GHz, which is close to the primary GPS transmission frequencies near 1.6 and 1.2 GHz. Many radio bursts have characteristic minima in their spectra in the low-GHz range, with adjacent increases both towards lower frequencies (coherent dm-metre-wave emission) and towards higher frequencies (incoherent gyro-synchrotron emission). The bursts that created disturbances of GPS transmission were exceptional in that they displayed particularly intense coherent emissions at 1.4 GHz. We report results of a systematic search for such features.
4	Remote monitoring of solar wind perturbations using MEXART at 140 MHz	Mejia-ambriz, J et al.	p-Poster
	J. C. Mejia-Ambriz[1], J. Gonzalez-Esparza[1], O. Chang-Martinez[2], V. De la Luz V[1], P.  Corona-Romero[1], L. X. Gonzalez[1], E. Aguilar-Rodriguez[3]
	[1] SCiESMEX, Instituto de Geofisica, Unidad Michoacan, Universidad Nacional Autonoma de Mexico, Morelia, Mexico; [2] Posgrado en Ciencias de la Tierra, Universidad Nacional Autonoma de Mexico; [3] Instituto de Geofísica, Unidad Michoacán, Universidad Nacional Autonoma de Mexico
	We show the scope of the Mexican Array Radio Telescope (MEXART) to monitor the solar wind in the inner heliosphere by using the interplanetary scintillation (IPS) technique at 140 MHz. Radio signals from astronomical sources are scattered by solar wind irregularities producing a moving diffraction pattern at Earth, which is observed by radio telescopes as fluctuations in the intensity of the sources and is known as IPS. IPS technique is used to remote sensing solar wind speed and densities, also with the use of several radio sources per day it is possible to reconstruct the 3-D dynamics of the solar wind including predictions. The longitude location of MEXART allows to track solar solar wind during night time side of the other existing IPS radio systems. Here we show the capabilities of MEXART to complement these other IPS observatories and produce its own products. MEXART is part of the network of instruments of the Mexican Space Weather Service (SCiESMEX).
5	The geomagnetic control of the ionospheric long-term trends has stopped in the 21 century?	Perrone, L et al.	p-Poster
	A. Mikhailov[1] and L. Perrone[2]
	[1] Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation (IZMIRAN), Troitsk, Moscow 142190, Russia ; [2] Istituto Nazionale di Geofisica e Vulcanologia (INGV), Via di Vigna Murata 605,  Roma 00143, Italia
	The greenhouse hypothesis of the ionospheric long-term trends is still very popular despite obvious and well-known contradictions with the observations. It fails to explain the observed foF2 and foF1 long-term trends at middle latitudes. On the other hand, earlier proposed the geomagnetic control concept of ionospheric trends relates the trends with long-term variations of geomagnetic activity, i.e. the ionospheric trends have a natural origin rather than an anthropogenic one. Recent ionosonde foF2 and foF1 observations over European stations were analyzed to check the validity of the geomagnetic control concept. A pronounced decrease of Ap132 (11-year running mean Ap index) after 1990 was followed by a positive trend in foF2 and foF1 for daytime hours in accordance with the geomagnetic control concept but only until 2000-2003. Since then negative foF2 and foF1 trends took place until at least 2009 (the last available point provided by the applied method of analysis). Therefore one may speak about the end of the geomagnetic control in the 21century. Synchronous foF2 and foF1 trends may be only explained by the thermosphere neutral composition (mainly atomic oxygen) variations. Possible mechanisms of the neutral composition variations are discussed.
6	Investigation of the Earth's inner magnetosphere with an electric field sounder onboard the Cluster satellites and a VLF antenna installed in Belgium	Darrouzet, F et al.	p-Poster
	Fabien Darrouzet[1], Viviane Pierrard[1], Johan De Keyser[1], Sylvain Ranvier[1], Pierrette Décréau[2], Janos Lichtenberger[3]
	[1] Belgian Institute for Space Aeronomy (IASB-BIRA) 3 Avenue Circulaire 1180 Brussels BELGIUM; [2] Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E) Orléans FRANCE; [3] Department of Geophysics and Space Sciences Eötvös University Budapest HUNGARY
	The four Cluster satellites have been launched in Summer 2000 to study the Earth's magnetosphere. The mission celebrates its 15th anniversary this year !! Onboard each spacecraft, the WHISPER (Waves of HIgh frequency and Sounder for Probing of Electron density by Relaxation) instrument measures the electric field in the frequency range 2–80 kHz, with a frequency resolution of 0.163 kHz and a time resolution of 2.1 s in normal mode. It can unambiguously identify the electron plasma frequency $F_{pe}$, which is related to the electron density $N_e$ that is an important parameter to analyze the Earth's magnetosphere. In active mode, the sounder analyses the pattern of resonances triggered in the medium by a radio pulse, thus allowing the identification of $F_{pe}$. In passive mode, the receiver monitors the natural plasma emissions and an independent estimation of $F_{pe}$ can be deduced from local wave cut-off properties. The Cluster spacecraft cross the inner magnetosphere around perigee, and in particular the plasmasphere. The variations of their perigee altitude during the entire mission(from 4 to 2 $R_E$) allow different types of crossings and different types of studies. During the plasmaspheric crossings with higher perigee (around 4 $R_E$), plasmaspheric plumes are frequently observed. Some statistical analysis of plumes based on several years of Cluster data will be presented. We also examine small-scale density structures insides plumes and EMIC (ElectroMagnetic Ion Cyclotron) waves related to plumes. With the lower perigee (around 2 $R_E$),the radiation belts are also crossed by the Cluster satellites. This offers an exceptional opportunity to analyze the position of the plasmapause and the position of the radiation belts boundaries with identical spacecraft. We present a statistical analysis of the locations of those boundaries based on 2 years of Cluster data. Density measurements obtained from the Cluster satellites can also be compared with ground-based determination of the density from whistlers waves, which are VLF emissions initiated by lightning, propagating along magnetic field lines. A VLF antenna has been installed in early 2011 in Belgium. It is made of two perpendicular magnetic loops, oriented North-South and East-West, and with an area of approximately 50 $m^2$ each. This antenna is part of AWDAnet, the Automatic Whistler Detector and Analyzer system's network. This network covers low, mid and high magnetic latitudes, including conjugate locations. We use the AWDA system to automatically retrieve electron density profiles from whistler measurements made in Belgium. We present results of whistler occurrence obtained from the antenna device, as well as some comparison with density measurements made with Cluster.
7	Long Term Trend of the ionospheric parameters at Rome station: Checking the geomagnetic control concept	Perrone, L et al.	p-Poster
	L. Perrone[1], L.  Alfonsi[1], C. Cesaroni[1], A. De Santis[1], M. Pezzopane[1], C. Scotto[1],  and A. Mikhailov[2]
	[1] Istituto Nazionale di Geofisica e Vulcanologia (INGV), Via di Vigna Murata 605,  Roma 00143, Italia; [2] Pushkov Institute of Terrestrial Magnetism, Ionosphere and Radio Wave Propagation (IZMIRAN), Troitsk, Moscow 142190, Russia
	For explaining the ionospheric long-term trends, the geomagnetic control concept is the only alternative to the greenhouse hypothesis which is widely spread and popular. However, it should be stressed that there are no direct confirmations (except the ones given by the model simulations) that ionospheric long-term trends are related to the CO2 increase. Moreover, the observed foF2 long-term trends are generally much larger than model predicted and their morphology cannot be reconciled with the greenhouse hypothesis. To study in depth this conundrum, long-term ionospheric trends have been calculated for Rome using all available ionosonde observations from 1958 to the present. An obvious dependence of foF2 and foF1 daytime trends on the long-term variations of geomagnetic activity (Ap132) has been confirmed until  2002. However, despite a continuous decrease in geomagnetic activity a pronounced negative foF2 and foF1 trends take place after 2002 indicating a break down of the geomagnetic control. This implies that some new processes have been likely involved which strongly control the ionospheric parameter long-term variations. An interpretation of the more recent strong negative trend is proposed using thermospheric parameters retrieved form Ne(h) ionosonde observations.
8	Ionospheric critical frequency prediction service based on digisonde measurements at Dourbes	Sapundjiev, D et al.	p-Poster
	D. Sapundjiev, S. Stankov
	Royal Meteorological Institute (RMI), Ringlaan 3, B-1180 Brussels, Belgium
	Presented is an operational service for high-resolution monitoring and prediction of the ionospheric F-layer critical frequency, foF2. The service is based on the recently developed monthly median model of foF2 using the extensive database of the RMI Geophysical Centre in Dourbes (50.1°N, 4.6°E). The model utilizes data from several solar cycles and uses the solar radio flux index (F10.7) as a solar activity measure. Provided is a preliminary evaluation of the service, including the advantages, uncertainties and shortcomings. Future applications and possible model improvements are also discussed.
9	Space weather observations to study the dynamics of the plasmapause and of the inner magnetosphere	Pierrard, V et al.	p-Poster
	Pierrard V., Darrouzet F.
	Belgian Institute for Space Aeronomy
	The dynamics of the plasmapause position and of the electron outer belt boundaries is studied with satellite observations and then compared with physics-based dynamical simulations. The plasmapause position is determined using the instrument WHISPER (Waves of HIgh frequency and Sounder for Probing of Electron density by Relaxation) onboard the CLUSTER satellites. The relationship between plasmapause positions, solar wind parameters and geomagnetic indices is analyzed at highest correlation time-lag. The results show a short time delay in the post-midnight MLT sector, but a time delay increasing with the MLT sector, in good agreement with the simulations of plasmapause formation based on the quasi-interchange mechanism. These plasmapause positions are also compared with the boundaries of the outer electron belt, as determined by CIS and RAPID instruments on CLUSTER. The dynamics of the radiation belts is also analyzed with the observations of the Energetic Particle Telescope (EPT) instrument, a new compact and modular ionizing particle spectrometer that was launched in May 2013 on board the PROBA-V satellite to a LEO polar orbit at an altitude of 820 km. The different plasma populations of the inner magnetosphere are found to be closely related, especially during storm events when the plasmapause and the inner edge of the outer belts move simultaneously closer to the Earth. The plasmapause is nevertheless more dynamic and comes back rapidly to larger radial distances after the storms while the inner edge of the outer belt remains closer the Earth during several days.
10	Towards a physics-based model for meteor interaction with Earth atmosphere	Dias, B et al.	p-Poster
	Bruno Dias[1], Alessandro Turchi[1], Thierry Magin[1], Johan De Keyser[2], Hervé Lamy[2]
	[1] von Karman Institute for Fluid Dynamics, Belgium; [2] Belgian Institute for Space Aeronomy, Belgium
	More than 50 tonnes of meteoritic material is estimated to be released into the Earth’s atmosphere every day. Meteors are small and fast, which makes them hard to detect in situ with space-borne instruments or with remote sensing techniques. Recent efforts have been made by the Belgian Institute for Space Aeronomy (BIRA-IASB) in order to predict velocity, trajectory and composition by means of an innovative technique based on radio waves. The Belgian Radio Meteor Stations (BRAMS) experiment, consists in a series of receivers spread all over Belgium to collect and standardize the meteor observations. One of the main objective of this experiment is the computation of the meteoroid flux densities. However, this quantity is hardly quantifiable from the lone radar observation, and it is necessary to rely on comparison with numerical models to have an estimate of it. In this scenario, the necessity of having the capability to numerically reproduce the meteor entry find its room. Similarly to hypersonic entries of spacecraft, when meteors interact with the atmosphere, their surface temperature can reach more than 2000 kelvins leading to their degradation by ablation. Afterwards, the ablation products are driven to the wake. Most of today’s simulation tools for meteor atmospheric entries rely on a simplistic zero dimensional approach, based mostly on ad hoc correlations for the physico-chemical models, describing for instance ablation and radiation. Therefore, it exist a necessity to develep more accurate tools to allow for “physics-based” simulations of the meteor phenomenon, as opposed to the “correlation-based” conventional simulations. By developing state-of-the-art ablation and radiation models, apply them to study meteor entries by means of CFD tools, it will be possible to compute the meteor characteristics (speed, composition and size population) from their signature in the BRAMS database. More specifically, the envisioned numerical models will allow us to predict the free electron concentration in the wake of meteors (important for the interpretation of radio observations), as well as the deposition of the ablation products into the atmosphere. As a first step, the present work is focused on low entry-velocity meteors, at altitudes lower than 70 km, to study their ablation. It is applied a strategy based on an aerospace-engineering-derived approach (i.e., steady-state CFD with surface ablation model). A boundary condition to describe the interaction between the atmosphere and objects with a complex elemental composition is developed. This interaction is modeled by solving an open-system multi-phase chemical equilibrium problem (i.e., gas-solid) by means of a solver able to handle materials composed by multiple compounds. This tool, fully coupled with the CFD solver allows for the computation of the gas composition at the gas-solid interface. Stagnation-line simulations for meteors of different sizes and compositions are performed, showing significantly different behaviors although all the computed mass blowing rates result rather small.
11	Modelling of Atmosphere Ionization by Energetic Electron Precipitation Based on Canada VLF Receivers Network Response	Kouznetsov, A et al.	p-Poster
	Alexei Kouznetsov, Christopher Cully, Laura Mazzino, Eric Davis
	University of Calgary, Alberta, Canada
	Energetic electron precipitations cause atmospheric ionization - a complicated process which depends on many parameters. The primary source of energetic electrons, the Van Allen radiation belts, occupy a vast region of space and accumulate an immense amount of energy. In the Northern hemisphere, they map to a broad ring crossing Canada. Under certain conditions, trapped electrons can penetrate even deeper into the atmosphere causing modulations of free electron densities of D-Layer affecting VLF propagation. Therefore, we are working towards developing an Energetic Electron Precipitation Model. The proposed energetic particles precipitation model consists of three main parts: • Energetic electron sources description; • Coupled electron/photon transport in the earth atmosphere; • Very Low Frequency (VLF) receivers response to energetic electron precipitations. The model is based on the coupled electron/photon transport implemented in the 6-th release of MCNP general transport code. The calculated electron density altitudinal profiles are used to construct and validate a realistic transport model that maps energetic electron fluxes incident on the upper atmosphere to the responses of VLF receivers instruments.