MAGDAS Project: Research for Global Electromagnetic Coupling from Polar to Equatorial Ionosphere

MAGDAS project: Research for global electromagnetic coupling from polar to equatorial ionosphere

Current distribution from polar to equatorial ionosphere

auroral zone

dusk

- side terminator side dip equator

sideterminator

dawn

auroral zone

no-Hall divergence effect Cowling channel Hall polarization component

Akimasa Yoshikawa[1,2]

[1] International Center for Space Weather Science and Education, [2] Department of Earth and Planetary Sciences, Kyushu University, Japan

1 "International Center for Space Weather Science and Education, Kyushu University (ICSWSE:2012-)

The Space Environment Research Center (SERC: Director Prof. K Yumoto) of Kyushu University (2002-2012:March) was re-organized on 01 April 2012. On that date it became the “International Center for Space Weather Science and Education ”.

The purpose for this re-organization is to allow space weather research to continue on a more global basis, and to establish a permanent international center for space weather science and education.

This center was also specifically requested as a part of the International Space Weather Initiative (ISWI) in the "Abuja ISWI Resolution" which was unanimously approved by the participants of the “UN/Nigeria Workshop on ISWI” (Abuja, Nigeria, 2011).

the purpose of ICSWSE

・Expansion and promotion of Space Weather as a field of science ・Closer investigation of changes of climate/geospace/disasters ・Examination of the medical and biological aspects of man working in space ・Realizing international space weather research and education

2 MAGDAS/CPMN (MAGnetic Data Acquisition System/Circum-pan Pacific Magnetometer Network) project

The equatorial magnetometer network (EMN) started in 1985. The 210MM network started in 1990.

The EMN and 210 MM are combined as the CPMN started in 1996.

We started installing MAGDAS in 2005.

The present total number of observational sites about 150. Currently, over 80 magnetometers and 4 FM-CW (Frequency Modulated Continuous Wave) radars are in operation for space weather study 3 Why global network observations of Magnetically quiet day geomagnetic field disturbances?

・Visualization of Space weather map from global magnetic field data

×観測点

Start of magnetic storm

Magnetic field variations on the ground are generated by reflecting ・space environment monitoring by using space weather index

（１）「solar terrestrial coupling」 electromagnetic disturbances across the We can investigate magnetosphere and ionosphere

・influences to Earth system caused （２）「horizontal coupling 」 solar eruptions electromagnetic energy is distributed from polar to equatorial ionosphere ・relation between solar activity and and atmospheric energy is vice versa climate phenomena and/or climate change

（３）「atmospheric vertical coupling」・global circulation of energy and propagation of lower atmospheric material of upper atmosphere disturbances to upper atmosphere via gravity wave and tidal waves, … ・relations between seismic activity and solar activity?

これらを同時に且つ広域に調査できるデータは磁場変動データのみ

Super Multipoint Geomagnetic field Network Observation ：important tool for exploring of Frontier of Solar terrestrial coupling process Electromagnetic coupling from polar to equatorial ionosphere

magnetic dip-equator:

• final destination of solar wind-magnetosphere- ionosphere coupling Auroral Electrojet (AEJ) • Most active region of atmospheric dynamic by solar radiation • anomalously enhanced zonal conductance is aligned ? ? along the dip-equator by the Cowling effect ? • sensitive receiver of solar wind variation, storm and substorm distrbances and atmospheric dynamo • many observational results of electric field penetration Equatorial Electrojet (EEJ) from polar to equatorial region • electromagnetic channel from auroral to equatrial ionosphere is unknown • closure of equatrial electrojet (EEJ) is still unknown Search for Current Closure from Polar to Equatorial Ionosphere through formation of Cowling Channel (ionospheric current induced by R1-type FAC closure at polar region )

auroral zone

Auroral Electrojet: AEJ

dusk - dip equator terminator side

sideterminator Equatorial Electrojet: EEJ

dawn

AEJ

auroral zone

Yoshikawa et al., 2012

・equator ward meridional current flows along the dawn-side terminator line and connecting between AEJ and EEJ

・equator ward meridional current at morning side also runs into the equator, and enhances the EEJ

・EEJ gradually decreases through diversion to the poleward current at evening side Hall part Pedersen part

・at the dawn side terminator, Hall and Pedersen currents in the east-west direction are cancelled out each other, while equator- ward Hall and Pedersen currents flow in the same direction ・at the dip-equator, Hall and Pedersen currents in the north-south (downward and upward) direction are cancelled out each other, while eastward Hall and Pedersen currents flow in the same direction

・Hall current runs into the equator at the morning side, while the Pedersen current diverging to the poleward at the evening side

The EEJ is the Cowling current of which continuity is preserved by connection via Cowling current along the dawn-terminator, Hall current converging from polar to dip-equator, and Pedersen current diverging from dip-equator to polar region !! Example of empirical approach for global current system formation

Global equivalent current system of dayside Pi2 pulsations

as a result of R1-type current wedge system oscillation?

Chapter 4. Spatial Features and Equivalent Current Distribution of Dayside Pi2 Pi2 pulsation is well-know as manifestation of substorm onset. Pulsation 62 It is a global pulsations observed not only night side region but also Chapter 4.daysideSpatial Features region. and Equivalent Current Distribution of Dayside Pi2 Pulsation 54 current perturbation magnetic perturbation on the ground (a) (b) (c)

1.0 1.0 1.0 HON 0.8 0.5 0.5 0.6 0.0 0.0 [nT] 0.4 [nT] [nT] ASB A 0.2 ASB H -0.5 ASB D -0.5 MLT= 8.6h MLT= 8.6h MLT= 8.6h GMLat.=37.0 0.0 GMLat.=37.0 -1.0 GMLat.=37.0 -1.0 TUC 1.0 1.0 1.0 auroral region 0.8 0.5 0.5 0.6 0.0 0.0 [nT] [nT] [nT] 0.4 HON A 0.2 HON H -0.5 HON D -0.5 MLT=12.3h MLT=12.3h MLT=12.3h GMLat.=22.7 GMLat.=22.7 GMLat.=22.7 0.0 -1.0 -1.0 DAV 1.0 1.0 1.0 ASB 0.8 0.5 0.5 0.6 0.0 0.0 [nT] 0.4 [nT] [nT] TUC A 0.2 TUC H -0.5 TUC D -0.5 MLT=15.3h MLT=15.3h MLT=15.3h GMLat.=40.4 GMLat.=40.4 GMLat.=40.4 0.0 Tue Jan 12 14:31:02 2016 -1.0 Tue Jan 12 14:31:04 2016 -1.0 Tue Jan 12 14:31:07 2016 hhmm 2330 2340 hhmm 2330 2340 hhmm 2330 2340 2012 Mar 02 2012 Mar 02 2012 Mar 02

90 90 Dusk Dawn (d) (e) 60 60

30 30

0 0

-30 -30 GM Lat. [deg] GM Lat. [deg]

-60 1nT -60 1nT -90 2012-03-02/23:34:05 -90 2012-03-02/23:34:40 0 3 6 9 12 15 18 21 24 0 3 6 9 12 15 18 21 24 MLT [h] MLT [h]

90 90 (f) (g) 60 60

30 30

0 0

-30 -30 Oscillatory FACs GM Lat. [deg] GM Lat. [deg]

-60 1nT -60 1nT -90 2012-03-02/23:35:14 -90 2012-03-02/23:36:15 0 3 6 9 12 15 18 21 24 0 3 6 9 12 15 18 21 24 MLT [h] MLT [h]

Figure 4.9: Filtered magnetic data for 2052 2112 UT on 26 March 2012 and the distributions of equivalent currents at the four− successive times in the same format as Oscillatory current source Figure 4.8 Figure 4.16: Schematic illustration of the current system to explain equivalent current distributions of dayside Pi2. Green arrows indicate magnetic perturbations, and red Imajo et al., [JGR, 2018] stream lines indicate current closures. Magnetic perturbations produced by mainly FACs are represented by δBFAC, and magnetic perturbations on the ground produced by mainly ionospheric currents are represented by δBIC. analysis. The correlationdepict the function equivalent (R(τ)) is current calculated system in the intervalof dayside of Tmax region,150 swhich to can be − Tmax +150sas:interpreted by the global Cowling channel

Tmax+150 R(τ)= AHON(t)ASTN(t τ)dt (4.1) !Tmax−150 −

2 2 where ASTN(t)is√∆H + ∆D at STN and τ is a lag ( 90 τ 90 s). The delay − ≤ ≤ time is determined by τ when the R(τ)isamaximumpeak.Toavoidanalyticalerrors, the delay time was only used in the analysis when maximum R(τ)wasgreaterthan 0.75. About 78% and 86% of the events satisﬁed this threshold for ASB and TUC, respectively.

Figure 4.10 shows typical examples of the selected events. ∆TASB and ∆TTUC are time delays of AASB and ATUC from AHON,respectively.The∆TASB and ∆TTUC are small and positive. The waveforms show that ASB D is in nearly antiphase with TUC D. The amplitude of HON H is much larger than that of HON D.TheamplitudeofASB How ionospheric polarization effect deform the ionospheric convection ?

Higher conductivity region JP Lower conductivity region JP Polarization effect by E0 B0 Pedersen current divergence -- - +++

2 + Σ ∇ S + ∇Σ ⋅ E − ∇S ! 0 + + - - - P 1 P ()0 1 Induces polarization charge density polarization E-field ⇅ expansion/compression of stream line ⇅ deceleration/acceleration of ionospheric convection

Cause of Cowling channel Polarization effect by - + Hall current divergence - + E0 J - + H + - 2 ˆ ' ΣP∇ S2 − ()n × ∇Σ H ⋅()E0 − ∇S1 ! 0 + - + - Induces polarization charge density ⇅ reflation of stream line Yoshikawa et al., [JGR 2013a,b] ⇅ Yoshikawa and Fujii, [AGU book 2018] Rotation/deformation of ionospheric convection Application: Formation of Harang reversal by Hall polarization field at auroral boundary region ?

Cause of twisting potential

Harang reversal of convection can be produced by Cowling effect??

Background potential Hall polarization potential Total potential

auroral oval

Hall current produced by -- - Cause of secondary potential symmetric +++ background potential across the auroral oval

Do they feed back to the magnetospheric system or not ? Development of Equatorial Electrojet observational network for space weather monitoring Geomagnetic disturbances at magnetic dip-equator Solar Wind Wind Solar IMF Bz Global

SC Magnetosphere Ring current !" Substorm Ionosphere Ionosphere

DP2 Local EEJ・CEJ

Sq Atmosphere Atmosphere SSC Chapman-Ferraro current

EEJ DP2

Polar Disturbance

dusk

- side terminator side dip equator CEJ Substorm

sideterminator

- Ring Current

dawn

auroral zone Visualization of Sq-Equivalent current 12

geomagnetically quiet days study of space climatology

・atmospheric dynamo (metrological phenomena) drives geomagnetic field disturbances

Coupling between solar activity and Atmospheric dynamics

study of space weather ・Strong disturbances in the magnetosphere

Space weather phenomena causes

・failures of satellite system

・irradiation of astronauts, crew of aircraft

・Ground induced current (GIC) Coupling between solar activity affects on the power line ,Magnetospheric dynamics and Ionospheric disturbances ・Serious GPS signal error by scintillation of electron density 13 Development of dense array of EEJ across dip equator after 2016 Peru region (newly installed after 2016) 10 Malaysia region Station GG lat GG lon GM lat GM lon Dip lat 5 LKW 6.3 99.78 -3.3 172.44 -1.07 JRS 0 LAN 5.95 116.68 -3.61 189.27 -1.02 -5 TPT Dip Equator TER 5.4 103.08 -4.26 175.71 -1.86 TMA -10 ANC HUA PER 3.72 101.53 -5.92 174.14 -3.59 -15 ICA BTG 2.78 101.51 -6.86 174.1 -4.53 -20 JOH 1.53 103.87 -8.14 176.46 -5.7 Station-25 GG lat GG lon GM lat GM lon Dip lat TMA -9.31 -76 0.36 -3.33 2.45

Geographic latitude [degree] -30

ANC -35 -11.77 -77.15 -2.11 -4.43 0.03

HUA -40 -12.02 -75.29 -2.34 -2.61 -0.31 ICA -14.09 -75.74 -4.42 -3.03 -2.35 -45 -90 -85 -80 -75 -70 -65 -60 -55 -50 -45 -40 -35 -30 2D EEJ structure reproduced from dense array data Geographic longitude [degree]

(Right) Noon time latitudinal variation of magnetic field change by ionospheric current (after Luhr et al., 2004). Red dots denote MAGDAS observatories in Peru.

・Average variation of EEJ, including current density and its structure, can be derived by satellite observation, but ground observations are necessary for monitoring EEJ activity every time. ・Dense array across EEJ enables real time monitoring of “breathing/ pulsing of EEJ”. that might be closely related to the scintillations caused by “Spread F” and /or “Plasma Bubble”. EEJ structures observed Peruvian dense magnetometer array

Example of EEJ current structure Example of EEJ curret structure during during quiet and normal EEJ storm time

Daily variation of H- and D-component.

Shifted EEJ peak Negative variation Double peak structure Equatorial enhancement of daily variation derived in the morning by subtracting of PIU, as the reference of Sq Previous maintenance Initial phase of magnetic storm main phase of magnetic storm recovery phase of magnetic storm variation. Matsushita, Ph.D. thesis, 2017 14 Real-time 24-hours Monitoring of Equatorial Electrojet variations

(Uozumi et al., [2008], Fujimoto et al., 2016) Method of EE-index (EWA) Observational sites around all over the dip-equator CEB ABU BCL EENH(DAV/MUT) = EUEL(DAV)－EUEL(MUL) CDO 200 Night time (LT=18-06) ICA 150 Equatorial Enhancement ANC, ICA 100 nT DAV EUS 50 EUS

disturbances ABJ 0 MUT ABJ EE-index in Storm-time -50 ILR, ABU ILR, ABU -100 2 4 6 8 10 12 14 16 18 20 22 AAB LT AAB Use as the dynamic reference base level for the daily variation global Representing magnetospheric TIR LKW, BCL CEB, DAV, CDO YAP (EWA) UT ・monitor the equatorial magnetic field variations changing EE=EUEL+ EDST from “moment to moment” local component Global component with the same ruler regardless of magnetospheric condition(quiet/disturbance) “EE=＋EUEL+EDst” calculated by MAGDAS EDst is defined as mean night time variation along Mag. Eq. EDst shows similar variation as Dst

EU/EL EDst

EDst represents global magnetic variation (almost same the Dst index)

EU/EL represents local magnetic variation (like AU/AU @ auroral zone) (but keep the variation form)

EDst can be utilized as the base level for the EEJ and CEJ This is one of the application research of EE-index.

Relationship between the occurrence of plasma bubble and EEJ/CEJ at South-Eastern Asia

Uemoto et al. (2010) integrated amplitude of EEJ CEJ

relationship EEJ and plasma bubble occurrence using resudual EEJ (EEJ-Sq value) （１）No-relation between amplitude of equatorial enhancement of component of “dayside” EEJ and plasma bubble occurrence

（２）Enhancement of pre-sunset CEJ strongly suppress bubble occurrence

→ how about total amplitude of EEJ including Sq field itself ?? 17 Relationship between the occurrence of plasma bubble and EEJ/CEJ There is no correlation between EEJ and bubble at southern Asia previous study.

@ Indonesia

EEJ only for equatorial enhancement part Uemoto et al. (2010)

South eastern Asia

Positive correlation between EEJ and LKW@ Malaysia bubble

Total EEJ amplitude including Backgrounfd Sq component

Bubble data (S4-index) is provided by ISEE Nagoya Univ

South America No correlation between EEJ and ICA and HUA@ Peru bubble

Total EEJ amplitude including Backgrounfd Sq component

Bubble data is provided by Lowell Digisonde International relationship EEJ strength using resudual EEJ (top panel), and integrated EUEL (middle and bottom panel) and plasma bubble occurrence rate. Akimoto Ms thesis 2019 18 Relationship between the occurrence of plasma bubble and EEJ/CEJ

Plasma bubble

No relation Relation No relation

Enhancement EEJ+Sq EEJ+Sq component of EEJ, (Asia) (south america) (removed Sq) Akimoto Ms thesis 2019 Akimoto Ms thesis 2019 (Asia) [Uemoto 2010]

Hamid [et al., 2014] report Sq-field is strong in Asian region but small in south American region

Dayside EEJ+Sq components at dayside region may strongly related to the plasma bubble occurrence at nightside region?

19 Space Weather Environment Index

Higher Freq. Variations of magnetic field monitor the space weather

Pc5 ULF waves DP2 disturbances The proxy of the Penetration of solar wind high energy energy electron (the Interplanetary acceleration in the Electric Field) into the radiation belt during equatorial ionosphere via magnetic storms the polar ionosphere

Counter Electrojet

Polar disturbance effects to Equatorial Electrojet 20 Space Climatological Environment Index

From day to day variation to Solar cycle variation Solar cycle →atmospheric cycle → EEJ variability atmospheric dynamics External Sq Current Intensity Solar cycle Variation Day-to-day variation

The dependence of the The atmospheric EEJ structure and the disturbances affecting atmospheric motion ionospheric dynamics related to EEJ on the solar activity/solar cycle [Fujimoto et al., 2016] Avg. EUEL@DAV

6.0 day?

The long-term variation of daily EEJ peak intensity has a trend similar to that of F10.7 (the solar activity). 21 Seismo-Eloctromagnetic Monitoring Network Indonesia-Japan MAGDAS Project for Litho-Space Weather

BMKG: Metrological ,Climatological and Geophysical Agency of Indonesia

ICSWSE, BMKG, Chiba U. Geomagnetic disturbances related with Seismic activity

Case 1: 26 Dec. 2004 (M=9.0) Case 2: 28 Mar. 2005 (M=8.7) Case 3: 12 Sep. 2007 (M=8.5) Case 1

Pc3 pulsations! Case 2 Case 3

Ground-based magnetic activities near the seismic focus were enhanced at few weeks before the earthquake occurred . 23 Geomagnetic activity related with Volcanic activity

In 2011, the activity of the Aso volcano started in April and ended in June as it reported by the Japanese Meteorological Agency (JMA). A small phreatic eruption occurred at Naka-dake’s crater lake in April 2011. On Friday 13 May, the Naka-dake vent of Aso produced small (phreatic) explosions with a 500 m tall steam-and-ash plume. The alert level for the volcano was raised to 2 by the JMA. Moreover, the JMA reported that during 7-9 June, plumes from Aso rose to altitudes of 1.5-1.8 km.

KUJ: Kuju in Japan

Emad et al., 2017 DAW: Darwin in Australia (conjugate point of KUJ)

24 Study on the global distribution characteristics of Pc 1-2 geomagnetic pulsation with the 10Hz data of the MAGDAS system 1: Graduate School of Sciences, Kyushu University 2: Department of Earth and Planetary Sciences, Kyushu University 3: International center for space weather science and education, Kyushu university �� 1, �� ℎ��2, �� Toward3 ,Ground �� monitoring �� of EMIC4, �ℎ�� excitation ��3 : Global Monitoring of Pc2 pulsation (periods: 5-10 4:seconds) Department of information technology, Kyushu Institute of Technology

EMIC wave excited during Storm especially stomtime substorm causes energization of heavy ion at the inner magnetosphere. 1. Introduction The frequency range of EMIC wave for O+ and He+ is in Pc2 pulsations (5-10 seconds). 4. Analysis The magnetic field observed on the ground is affected by the space 1. Pc2 observed from polar to equatorial region by MAGDAS 2. Initial analysis of typical event (09/13/2014) weather phenomena such as magnetic storms and auroral storms. The By using the 10Hz data of MAGDAS-9 magnetometers, Pc2 By using the 10Hz data of MAGDAS-9 magnetometers, a global Pc2 pulsation with two-band structure disturbance phenomenon of the ground magnetic field that has the pulsation observed almost simultaneously from high-latitude area can be identified almost simultaneously during about 06:30-08:00UT on 13 September 2014. frequency range of approximately several to 1,000 seconds is generally near polar region to middle-and-low latitude area near the equator called geomagnetic pulsation. can be identified.

Geomagnetic pulsation is excited as results of reflections of various GG Lat. [°] space weather phenomena in geo-space. Particularly, understanding Increase of the TIK: 71.59 dynamic pressure

the occurrence and propagation mechanism ] ZGN: 66.47 about Pc1 and Pc2 pulsation is one of Notation Period Range [s] nT the principal themes in solar terrestrial Pc1 0.2-5 ASB: 43.46 Dst index [nT] physics because it is strongly suggested Pc2 5-10 KUJ: 33.06 Pc Recovery phase Pc3 10-45 : wind 09/13/2014 dataSolar ACE that Pc1-2 pulsation is related to the Continuous MUT: 14.37 Pc4 45-150 LT distribution [06:30UT] UT [MM/DD] UT [hh] excitation of the EMIC waves in inner Pulsation BCL: 09.32 Pc5 150-600 magnetosphere(Morley et al. 2009). H comp. [ Filtered Pc6 600- LKW: 06.30 This global Pc2 pulsation is distributed not only over the latitude direction widely but also both dayside and nightside. As for the characteristics of space environment, the global Pc2 pulsation occurred during the recovery phase of magnetic storm(-88nT), and solar wind dynamic pressure increased significantly.

2. Purpose Kabasawa,[2019], BC thesis UT [hh:ss]

are identified. [s] Period pulsation on the ground with EMIC waves excitation is very important Two-band structure One-band structure Two-band structure for space weather applications to be able to monitor the energization processes of magnetospheric particles via EMIC excitation. As the initial step to accomplish the purpose, we investigated ASB UT [hh:ss] KUJ UT [hh:ss] MUT UT [hh:ss] occurrence distribution characteristics of Pc1-2 pulsation by using This observed Pc2 has two-band structure, with one band above the frequency of 10 seconds and the ] MAGDAS(MAGnetic Data Acquisition System) network which ] other below the frequency of 10 seconds. However, the two-band structure is not be confirmed depending nT ICSWSE operates. In this presentation, we will report the preliminary nT on observation points. results of observational analysis of Pc2 pulsation mainly. A typical case of EMIC emissions with both AE indexAE [ Dst[ index ��+ band and �+ band waves was observed by 3. Data Van Allen Probe A on 14 July 2014(Yu et al., 2018). This is the case that EMIC waves by heavy ions Occurrence time of identified coincident Pc2 Analysis Period : 01/01/2012-12/31/2012 were observed in the internal magnetosphere. Two-band structure Typical Event : 09/13/2014 UT [DD] Also, it has two-band structure, with one band + Data : 1. Magnetic field data by MAGDAS-9 magnetometer above ��+(= the local gyrofrequencies of � ) and (provided by ICSWSE, Kyushu Univ.) The figure shows that Dst index tends to decrease and AE the other below ��+. It is suggested that this 2. Dst and AE index index tends to increase when the coincident Pc2 has occurred. As global Pc2 pulsation on the ground is likely to (provided by the WDC for Geomagnetism, Kyoto) for AE index, there is a distinct correlation that 18 out of 23 have close relation to the wave particle coincident events have occurred with large-scale substorms of interaction phenomenon by the high-energy heavy Used observation points which AE index is more than 1,000nT. ions in the internal magnetosphere. Yu et al. [2018] KTN(Kotel’ nyy) TIK(Tixie) CHD(Chokurdakh) ZGN(Zhigansk) YAK(Yakutsk) ASB(Ashibetsu) KUJ(Kuju) HLN(Hualien) 5. Discussion and Conclusion 6. Future task MUT(Muntinlupa) EWA(Ewa beach)BCL(Bac Lieu) LKW(Langkawi) TIR(Tirunelveli) DAW(Darwin) SMA(Santa Maria) 1. Pc2 observed from polar to equatorial region by MAGDAS In order to clarify the generation and propagation MAGDAS is the only By using the 10Hz data of MAGDAS-9 magnetometers, Pc2 pulsation can be identified almost simultaneously from mechanism of Pc2 pulsation, more detailed analysis world’s largest real-time high-latitude area near polar region to middle-and-low latitude area near the equator . From the statistical analysis is necessary by focusing on the ionosphere geomagnetic observation result, it is suggested that generation of Pc2 pulsation from high-latitude to middle-and-low latitude region and further structure. network using fluxgate arrival of Pc2 pulsation to the dip-equator is identified when the substorm have occurred during a magnetic storm time. Furthermore, the final goal of this study is to understand global coupling process among inner magnetometers, which 2. Initial analysis of typical event (09/13/2014) acquire 250Hz sampling magnetosphere and high-middle-low latitude to the and 10Hz mean data. It By using the 10Hz data of MAGDAS-9 magnetometers, a typical Pc2 event with two-band structure can be identified equatorial region by using MAGDAS multipoint data, can analysis the wave form globally during about 06:30-08:00UT on 13 September 2014. Also, Yu et al. [2018] reports the typical case of EMIC FM-CW radar data, PWING induction magnetometer and amplitude of Pc1-2 waves with similar two-band structure. Providing that waves are conducted via the ionosphere, it is considered that the data, and the geo-space environment data from the pulsation. difference in band structures among observation points is attributed to the ionosphere structure. ERG satellite. Study on the global distribution characteristics of Pc 1-2 geomagnetic pulsation with the 10Hz data of the MAGDAS system 1: Graduate School of Sciences, Kyushu University 2: Department of Earth and Planetary Sciences, Kyushu University 1 2 3 4 3 3: International center for space weather science and education, Kyushu university �� , �� ℎ�� , �� , �� , �ℎ�� 4: Department of information technology, Kyushu Institute of Technology

1. Introduction 4. Analysis The magnetic field observed on the ground is affected by the space 1. Pc2 observed from polar to equatorial region by MAGDAS 2. Initial analysis of typical event (09/13/2014) weather phenomena such as magnetic storms and auroral storms. The By using the 10Hz data of MAGDAS-9 magnetometers, Pc2 By using the 10Hz data of MAGDAS-9 magnetometers, a global Pc2 pulsation with two-band structure disturbance phenomenon of the ground magnetic field that has the pulsation observed almost simultaneously from high-latitude area can be identified almost simultaneously during about 06:30-08:00UT on 13 September 2014. frequency range of approximately several to 1,000 seconds is generally near polar region to middle-and-low latitude area near the equator called geomagnetic pulsation. can be identified.

Geomagnetic pulsation is excited as results of reflections of various GG Lat. [°] space weather phenomena in geo-space. Particularly, understanding Increase of the TIK: 71.59 dynamic pressure

In this research, the final purpose is to establish a theoretical Such Pc2 pulsation has similar waveforms among different model based on the global coupling process among inner observation points. Also, the amplitude in high latitude points is magnetosphere and ionosphere and Pc1-2 pulsation observed on the bigger than in middle-and-low points. In this analysis ground. Also, the elucidation of occurrence characteristics of Pc1-2 period(01/01/2012-12/31/2012), 23 such coincident Pc2 pulsation are identified. [s] Period pulsation on the ground with EMIC waves excitation is very important Two-band structure One-band structure Two-band structure for space weather applications to be able to monitor the energization processes of magnetospheric particles via EMIC excitation. As the initial step to accomplish the purpose, we investigated ASB UT [hh:ss] KUJ UT [hh:ss] MUT UT [hh:ss] occurrence distribution characteristics of Pc1-2 pulsation by using ThisTwo observed band Pc2 structure has two-band of EMIC structure, emission with one observedband above theby frequencyVan Allen of 10Probe seconds and the ] MAGDAS(MAGnetic Data Acquisition System) network which ] other below the frequency of 10 seconds. However, the two-band structure is not be confirmed depending nT ICSWSE operates. In this presentation, we will report the preliminary nT on observation points. results of observational analysis of Pc2 pulsation mainly. A typical case of EMIC emissions with both AE indexAE [ Dst[ index ��+ band and �+ band waves was observed by 3. Data Van Allen Probe A on 14 July 2014(Yu et al., 2018). This is the case that EMIC waves by heavy ions Occurrence time of identified coincident Pc2 Analysis Period : 01/01/2012-12/31/2012 were observed in the internal magnetosphere. Two-band structure Typical Event : 09/13/2014 UT [DD] Also, it has two-band structure, with one band + Data : 1. Magnetic field data by MAGDAS-9 magnetometer above ��+(= the local gyrofrequencies of � ) and (provided by ICSWSE, Kyushu Univ.) The figure shows that Dst index tends to decrease and AE the other below ��+. It is suggested that this 2. Dst and AE index index tends to increase when the coincident Pc2 has occurred. As global Pc2 pulsation on the ground is likely to (provided by the WDC for Geomagnetism, Kyoto) for AE index, there is a distinct correlation that 18 out of 23 have close relation to the wave particle coincident events have occurred with large-scale substorms of interaction phenomenon by the high-energy heavy Used observation points which AE index is more than 1,000nT. ions in the internal magnetosphere. Yu et al. [2018] KTN(Kotel’ nyy) TIK(Tixie) CHD(Chokurdakh) ZGN(Zhigansk) YAK(Yakutsk) ASB(Ashibetsu) KUJ(Kuju) HLN(Hualien) 5. Discussion and Conclusion 6. Future task MUT(Muntinlupa) EWA(Ewa beach)BCL(Bac Lieu) LKW(Langkawi) TIR(Tirunelveli) DAW(Darwin) SMA(Santa Maria) 1. Pc2 observed from polar to equatorial region by MAGDAS In order to clarify the generation and propagation Frequency range is in Pc2 pulsations (5~10 sec) MAGDAS is the only By using the 10Hz data of MAGDAS-9 magnetometers, Pc2 pulsation can be identified almost simultaneously from mechanism of Pc2 pulsation, more detailed analysis world’s largest real-time high-latitude area near polar region to middle-and-low latitude area near the equator . From the statistical analysis is necessary by focusing on the ionosphere geomagnetic observation result, it is suggested that generation of Pc2 pulsation from high-latitude to middle-and-low latitude region and further structure. network using fluxgate arrival of Pc2 pulsation to the dip-equator is identified when the substorm have occurred during a magnetic storm time. Furthermore, the final goal of this study is to understand global coupling process among inner magnetometers, which 2. Initial analysis of typical event (09/13/2014) acquire 250Hz sampling magnetosphere and high-middle-low latitude to the and 10Hz mean data. It By using the 10Hz data of MAGDAS-9 magnetometers, a typical Pc2 event with two-band structure can be identified equatorial region by using MAGDAS multipoint data, can analysis the wave form globally during about 06:30-08:00UT on 13 September 2014. Also, Yu et al. [2018] reports the typical case of EMIC FM-CW radar data, PWING induction magnetometer and amplitude of Pc1-2 waves with similar two-band structure. Providing that waves are conducted via the ionosphere, it is considered that the data, and the geo-space environment data from the pulsation. difference in band structures among observation points is attributed to the ionosphere structure. ERG satellite. Study on the global distribution characteristics of Pc 1-2 geomagnetic pulsation Study on the global withdistribution the 10Hz characteristics data of the MAGDAS of Pc 1-2 system geomagnetic pulsation 1: Graduate School of Sciences, Kyushu University 2: Department of Earth and Planetary Sciences, Kyushu University 1 2 3 4 3 3: International center for space weather science and education, Kyushu university �� , �� ℎ�� , ��with �� the, ��10Hz �� data, �ℎ�� of �� the4: Department MAGDAS of information technology,system Kyushu Institute of Technology 1: Graduate School of Sciences, Kyushu University 2: Department of Earth and Planetary Sciences, Kyushu University 11. Introduction 2 3 4 3 3: International center for space4. weather Analysis science and education, Kyushu university �� , �� ℎ�� , �� , �� , �ℎ�� 4: Department of information technology, Kyushu Institute of Technology The magnetic field observed on the ground is affected by the space 1. Pc2 observed from polar to equatorial region by MAGDAS 2. Initial analysis of typical event (09/13/2014) weather phenomena such1. asIntroduction magnetic storms and auroral storms. The By using the 10Hz data of MAGDAS-9 magnetometers, Pc2 TwoBy using band4. theAnalysis structure10Hz data of MAGDAS-9of Pc2 pulsation magnetometers, also a global observed Pc2 pulsation on thewith two-bandground structure disturbance phenomenon of the ground magnetic field that has the pulsation observed almost simultaneously from high-latitude area can be identified almost simultaneously during about 06:30-08:00UT on 13 September 2014. frequencyThe magnetic range field of approximatelyobserved on the several ground to 1,000is affected seconds by theis generally space 1.near Pc2 polar observed region from to middle-and-low polar to equatorial latitude region area nearby MAGDAS the equator 2. Initial analysis of typical event (09/13/2014) called geomagnetic pulsation. weather phenomena such as magnetic storms and auroral storms. The canBy beusing identified. the 10Hz data of MAGDAS-9 magnetometers, Pc2 By using the 10Hz data of MAGDAS-9 magnetometers, a global Pc2 pulsation with two-band structure disturbance phenomenon of the ground magnetic field that has the Geomagnetic pulsation is excited as results of reflections of various pulsation observed almost simultaneously from high-latitude area can be identified almost simultaneously during about 06:30-08:00UT on 13 September 2014. frequency range of approximately several to 1,000 seconds is generally GG Lat. [°] space weather phenomena in geo-space. Particularly, understanding near polar region to middle-and-low latitude area near the equator Increase of the called geomagnetic pulsation. TIK: 71.59 dynamic pressure the occurrence and propagation mechanism can] be identified. ZGN: 66.47 about Pc1 and Pc2 pulsation is one of Notation Period Range [s] nT

Geomagnetic pulsation is excited as results of reflections of various GGASB: Lat. [ 43.46°] Dst index [nT] spacethe principalweather phenomenathemes in solar in geo-space. terrestrial Particularly, understandingPc1 0.2-5 Increase of the physics because it is strongly suggested Pc2 5-10 TIK:KUJ: 71.59 33.06 dynamic pressure the occurrence and propagation mechanism Pc ] Recovery phase Pc3 10-45 ZGN:MUT: 66.47 14.37 : wind 09/13/2014 dataSolar ACE aboutthat Pc1 Pc1-2 and pulsation Pc2 pulsation is related is one to theof Continuous nT NotationPc4 Period Range45-150 [s] LT distribution [06:30UT] UT [MM/DD] UT [hh] excitation of the EMIC waves in inner Pulsation ASB:BCL: 43.46 09.32 Dst index [nT] the principal themes in solar terrestrial Pc1Pc5 0.2-5150-600 magnetosphere(Morley et al. 2009). H comp. [ Filtered physics because it is strongly suggested Pc2Pc6 5-10600- KUJ:LKW: 33.06 06.30 This global Pc2 pulsation is distributed not only over the latitude direction widely but also both dayside Pc Recovery phase Pc3 10-45 : wind 09/13/2014 dataSolar ACE that Pc1-2 pulsation is related to the Continuous MUT: 14.37 and nightside. As for the characteristics of space environment, the global Pc2 pulsation occurred during Pc4 45-150 LT distribution [06:30UT] UT [MM/DD] UT [hh] excitation of the EMIC waves in inner Pulsation BCL: 09.32 the recovery phase of magnetic storm(-88nT), and solar wind dynamic pressure increased significantly. Pc5 150-600 UT [hh:ss] magnetosphere(Morley et al. 2009).2. Purpose H comp. [ Filtered Pc6 600- LKW: 06.30 This global Pc2 pulsation is distributed not only over the latitude direction widely but also both dayside In this research, the final purpose is to establish a theoretical Such Pc2 pulsation has similar waveforms among different and nightside. As for the characteristics of space environment, the global Pc2 pulsation occurred during model based on the global coupling process among inner observation points. Also, the amplitude in high latitude points is the recovery phase of magnetic storm(-88nT), and solar wind dynamic pressure increased significantly. 2. Purpose UT [hh:ss] magnetosphere and ionosphere and Pc1-2 pulsation observed on the bigger than in middle-and-low points. In this analysis period(01/01/2012-12/31/2012), 23 such coincident Pc2 pulsation ground.In this research, Also, the theelucidation final purpose of occurrence is to establish characteristics a theoretical of Pc1- 2 Such Pc2 pulsation has similar waveforms among different are identified. [s] Period modelpulsation based on on the the ground global withcoupling EMIC process waves excitationamong inner is very important observation points. Also, the amplitude in high latitude points is Two-band structure One-band structure Two-band structure magnetospherefor space weather and ionosphereapplications and to bePc1-2 able pulsation to monitor observed the energization on the bigger than in middle-and-low points. In this analysis ground.processes Also, ofthe magnetospheric elucidation of occurrence particles via characteristics EMIC excitation. of Pc1-2 period(01/01/2012-12/31/2012), 23 such coincident Pc2 pulsation ASB UT [hh:ss] As the initial step to accomplish the purpose, we investigated are identified. [s] Period KUJ UT [hh:ss] MUT UT [hh:ss] pulsation on the ground with EMIC waves excitation is very important Two-band structure One-band structure Two-band structure foroccurrence space weather distribution applications characteristics to be able of to Pc1-2 monitor pulsation the energization by using This observed Pc2 has two-band structure, with one band above the frequency of 10 seconds and the ] MAGDAS(MAGnetic Data Acquisition System) network which ] other below the frequency of 10 seconds. However, the two-band structure is not be confirmed depending processes of magnetospheric particles via EMIC excitation. nT ICSWSE operates. In this presentation, we will report the preliminary nT As the initial step to accomplish the purpose, we investigated on observationASB points. UT [hh:ss] KUJ UT [hh:ss] MUT UT [hh:ss] results of observational analysis of Pc2 pulsation mainly. occurrence distribution characteristics of Pc1-2 pulsation by using This observed Pc2 has two-band structure, with one bandA abovetypical the case frequency of EMIC ofemissions 10 seconds with and both the ] AE indexAE [ ] MAGDAS(MAGnetic Data Acquisition System) network which Dst[ index other below the frequency of 10 seconds. However, the two-band��+ band structure and �+ band is not waves be confirmed was observed depending by nT nT ICSWSE operates. In this presentation,3. Data we will report the preliminary on observation points. Van Allen Probe A on 14 July 2014(Yu et al., 2018). results of observational analysis of Pc2 pulsation mainly. This is the case that EMIC waves by heavy ions Occurrence time of identified coincident Pc2 A typical case of EMIC emissions with both

Analysis Period : 01/01/2012-12/31/2012 indexAE [ were observed in the internal magnetosphere. Dst[ index + + Two-band structure �� band and � band waves was observed by Typical Event : 09/13/2014 UT [DD] Also, it has two-band structure, with one band Data : 1. Magnetic3. Datafield data by MAGDAS-9 magnetometer Vanabove Allen � (=Probe the Alocal on 14gyrofrequencies July 2014(Yu et of al.,�+ )2018). and This is the�+ case that EMIC waves by heavy ions (provided by ICSWSE, Kyushu Univ.) The figure showsOccurrence that time Dst ofindex identified tends coincident to decrease Pc2 and AE the other below ��+. It is suggested that this Analysis Period : 01/01/2012-12/31/20122. Dst and AE index index tends to increase when the coincident Pc2 has occurred. As wereglobal observed Pc2 pulsation in the oninternal the ground magnetosphere. is likely to Two-band structure Typical Event : 09/13/2014 UT [DD] Also, it has two-band structure, with one band (provided by the WDC for Geomagnetism, Kyoto) for AE index, there is a distinct correlation that 18 out of 23 have close relation to the wave particle + Data : 1. Magnetic field data by MAGDAS-9 magnetometer coincident events have occurred with large-scale substorms of aboveinteraction ��+(= phenomenon the local gyrofrequencies by the high-energy of � )heavy and Used observation (providedpoints by ICSWSE, Kyushu Univ.) whichThe figure AE index shows is more that thanDst index 1,000nT. tends to decrease and AE theions other in the below internal ��+ .magnetosphere. It is suggested that this Yu et al. [2018] KTN(Kotel’ nyy)2. TIK(Tixie) Dst and AE index CHD(Chokurdakh) ZGN(Zhigansk) index tends to increase when the coincident Pc2 has occurred. As global Pc2 pulsation on the ground is likely to (provided by the WDC for Geomagnetism, Kyoto) for AE index, there is a distinct correlation that 18 out of 23 have close relation to the wave particle YAK(Yakutsk) ASB(Ashibetsu) KUJ(Kuju) HLN(Hualien) 5. Discussion and Conclusion 6. Future task MUT(Muntinlupa) EWA(Ewa beach)BCL(Bac Lieu) LKW(Langkawi) coincident events have occurred with large-scale substorms of interaction phenomenon by the high-energy heavy Used observation points which AE index is more than 1,000nT. ions in the internal magnetosphere. TIR(Tirunelveli) DAW(Darwin) SMA(Santa Maria) Yu et al. [2018] KTN(Kotel’ nyy) TIK(Tixie) CHD(Chokurdakh) ZGN(Zhigansk) 1. Pc2 observed from polar to equatorial region by MAGDAS In order to clarify the generation and propagation mechanism of Pc2 pulsation, more detailed analysis YAK(Yakutsk) ASB(Ashibetsu) KUJ(Kuju)MAGDAS HLN(Hualien) is the only By using the 10Hz data of MAGDAS-95. Discussion magnetometers, and Pc2 pulsation Conclusion can be identified almost simultaneously from 6. Future task MUT(Muntinlupa) EWA(Ewa beach)BCL(Bac Lieu)world’s largest LKW(Langkawi) real-time high-latitude area near polar region to middle-and-low latitude area near the equator . From the statistical analysis is necessary by focusing on the ionosphere structure. TIR(Tirunelveli) DAW(Darwin) SMA(Santageomagnetic Maria) observation 1.result, Pc2 observed it is suggested from polarthat generation to equatorial of Pc2 region pulsation by MAGDAS from high-latitude to middle-and-low latitude region and further In order to clarify the generation and propagation network using fluxgate arrival of Pc2 pulsation to the dip-equator is identified when the substorm have occurred during a magnetic storm time. Furthermore, the final goal of this study is to MAGDAS is the only By using the 10Hz data of MAGDAS-9 magnetometers, Pc2 pulsation can be identified almost simultaneously from mechanismunderstand ofglobal Pc2 couplingpulsation, process more detailed among inneranalysis magnetometers, which 2. Initial analysis of typical event (09/13/2014) is necessary by focusing on the ionosphere world’sacquire largest 250Hz real sampling-time high-latitude area near polar region to middle-and-low latitude area near the equator . From the statistical analysis magnetosphere and high-middle-low latitude to the structure. geomagneticand 10Hz mean observation data. It result,By it using is suggested the 10Hz that data generation of MAGDAS-9 of Pc2 magnetometers, pulsation from ahigh-latitude typical Pc2 eventto middle-and-low with two-band latitude structure region can andbe identified further equatorial region by using MAGDAS multipoint data, Furthermore, the final goal of this study is to networkcan analysis using fluxgatethe wave form arrivalglobally of Pc2during pulsation about 06:30-08:00UTto the dip-equator on 13 is Septemberidentified when 2014. the Also, substorm Yu et al. have [2018] occurred reports during the typical a magnetic case of storm EMIC time. FM-CW radar data, PWING induction magnetometer understand global coupling process among inner magnetometers,and amplitude whichof Pc1- 2 2.waves Initial withanalysis similar of two-bandtypical event structure. (09/13/2014) Providing that waves are conducted via the ionosphere, it is considered that the data, and the geo-space environment data from the acquirepulsation. 250Hz sampling difference in band structures among observation points is attributed to the ionosphere structure. magnetosphereERG satellite. and high-middle-low latitude to the and 10Hz mean data. It By using the 10Hz data of MAGDAS-9 magnetometers, a typical Pc2 event with two-band structure can be identified equatorial region by using MAGDAS multipoint data, can analysis the wave form globally during about 06:30-08:00UT on 13 September 2014. Also, Yu et al. [2018] reports the typical case of EMIC FM-CW radar data, PWING induction magnetometer and amplitude of Pc1-2 waves with similar two-band structure. Providing that waves are conducted via the ionosphere, it is considered that the data, and the geo-space environment data from the pulsation. difference in band structures among observation points is attributed to the ionosphere structure. ERG satellite. 28 Data distribution

・The realtime quick-look plot (ordinary and time derivative) are available at http://data.icswse.kyushu-u.ac.jp/.

・ All MAGDAS data are available on request. We are developing web-based data sharing system, and will be opened in near future.

・A part of MAGDAS data have been opened through the ERG Science Center (for more details, http://ergsc.isee.nagoya- u.ac.jp/) as CDF format.

・Metadata of MAGDAS data have been opened through the IUGONET. 29

Capacity Building activity (2015-2018)

・MAGDAS training@ Malaysia and Peru (5x @ Malaysia, 2x @Peru) ・UN/JAPAN WS for the ISWI (2015) ・SCOSTEP School@Peru(2015), @ India(2016) ・COSPAR School@Russia(2016) ・JSPS Core to Core School@ Nigeria(2017), Indonesia(2018) (PI: Prof. Shiokawa-san) ・MAGDA-WS＠ Malaysia(2017、2018) ・UN/USA WS for the ISWI (2017)

・1Master student from Korea (2017-) How to handle the data.. How to install… ・Ph.D students from Malaysia (2017-), from Sri-Lanka ・Visiting Researcher from Egypt (2016-2017) ・Employment of Foreign Associate Prof. How to do science... 2015-2016 from Russia 2016-2017 from Philippine 2017-2018 from Finland 2019/Mar/25 AGS 2019@Cairo, Egypt

Education & Capacity Building Japan-Malaysia Joint Seminar on Space Weather and Electromagnetism and Intensive Course on Space Magnetohydrodynamics,2018/March/22-2018/March/29 at ICSWSE

What’s the fluxgate?

MHD seminar by Dr. Yoshikawa

IUGONET Hands on

30 2019/Mar/25 AGS 2019@Cairo, Egypt 31

Education & Capacity Building

Sensor hut Ø Dispatch graduate student to field work 65m main body Ø Space weather summary report room Ø Since October 2002, daily reports on

space weather have been issued by Setting the Main Body students. Ø Outreach activities on space weather

Ø Over 50 public lectures on Space 65 m Cabling weather science for children and general citizens in Japan. Ø Foreign students from Asian/African nations Ø 5 Ph D. holder from 4 nations Ø (Egypt, Sudan, Philippines, 2 from Malaysia)

Ø Over 80 MAGDAS paper were published after 2013 Over 80 MAGDAS paper were published after 2013-

1. M Abbas, ZZ Abidin, MH Jusoh, OS Bolaji, A Yoshikawa, Features of horizontal magnetic field intensity over northern island of Malaysia, Indian Journal of Physics, 1-112019. 2. Yoshikawa A., and R. Fujii (2018), Earth’s Ionosphere: Theory and Phenomenology of Cowling Channels, in Electric Currents in Geospace and Beyond (eds A. Keiling, O. Marghitu, and M. Wheatland), John Wiley & Sons, Inc, Hoboken, N.J., doi: 10.1002/9781119324522.ch25 3. R Shi, B Ni, D Summers, H Liu, A Yoshikawa, B Zhang, Generation of electron acoustic waves in the topside ionosphere from coupling with kinetic Alfven waves: a new electron energization mechanism, Geophysical Research Letters 45 (11), 5299-5304、doi: 10.1029/2018GL077898 4. Ohtani, S., Motoba, T., Gjerloev, J. W., Ruohoniemi, J. M., Donovan, E. F., & Yoshikawa, A (2018). Longitudinal development of poleward boundary intensifications (PBIs) of auroral emission. Journal of Geophysical Research: Space Physics, 123. https://doi.org/10.1029/2017JA024375 5. Seki, K., Miyoshi, Y., Ebihara, Y., Katoh Y., Amano T., Saito S., Shoji M., Nakamizo A., Keika K., Hori T., Nakano S., Watanabe S., Kamiya K., Takahashi N., Omura Y., Nose ., Mei-Ching Fok., Tanaka T., Ieda A., and Yoshikawa A (2018), Earth Planets Space (2018) 70: 17. https://doi.org/10.1186/s40623-018-0785-9 6. EM Takla, A Khashaba, MA Zaher, A Yoshikawa, T Uozumi (2018), Anomalous ultra low frequency signals possibly linked with seismic activities in Sumatra, Indonesia, NRIAG Journal of Astronomy and Geophysics doi: 10.1016/j.nrjag.2018.04.004 7. NSA Hamid, VA Wen, NIM Rosli, A Yoshikawa, Changes in Ionospheric Currents System at Southeast Asia Region during Geomagnetic Storm in Solar‘s Minimum Phase SAINS MALAYSIANA 47 (8), 1923-1929, 2018 8. R Umar, SF Natasha, SSN Aminah, KN Juhari, MH Jusoh, NSA Hamid, MH Hashim, ZM Radzi, AN Ishak, SN Hazmin, WZAW Mokhtar, MKA Kamarudin, H Juahir, A Yoshikawa (2018), Magnetic Data Acquisition System (MAGDAS) Malaysia: installation and preliminary data analysis at ESERI, UNISZA, Indian Journal of Physics, 1 9. Takahashi, N., Seki, K., Teramoto, M., Fok, M.‐C., Zheng, Y., Matsuoka, A., Nana Higashio, Kazuo Shiokawa, Dmitry Baishev, Akimasa Yoshikawa, Tsutomu Nagatsuma (2018). Global distribution of ULF waves during magnetic storms: Comparison of Arase, ground observations, and BATSRUS + CRCM simulation. Geophysical Research https://doi.org/10.1029/2018GL078857 10. NMN Annadurai, NSA Hamid, Y Yamazaki, A Yoshikawa，Investigation of Unusual Solar Flare Effect on the Global Ionospheric Current System, Journal of Geophysical Research: Space Physics, https://doi.org/10.1029/2018JA025601 11. NMN Annadurai, NSA Hamid, A Yoshikawa, Observation of Ionospheric Current during Strong Solar Flare Using Ground Based Magnetometer, SAINS MALAYSIANA 47 (3), 595-601 12. ZZ Abidin, MH Jusoh, M Abbas, A Yoshikawa (2018), Application of solar quiet (Sq) current in determining mantle conductivity-depth structure in Malaysia, Journal of Atmospheric and Solar-Terrestrial Physics, https://doi.org/10.1016/j.jastp.2018.01.019. 13. ZZ Abidin, MH Jusoh, M Abbas, OS Bolaji., and A. Yoshikawa (2018), Features of the inter-hemispheric field-aligned current system over Malaysia ionosphere, Journal of Atmospheric and Solar-Terrestrial Physics, https://doi.org/10.1016/j.jastp.2018.01.012. 14. Kasran F.A.M., Jusoh M.H., Yoshikawa A., Radzi Z.M., MAGDAS/CPMN Group (2018), The Time Derivative of the Horizontal Geomagnetic Field for the Low Latitude MAGDAS Langkawi Station for the Estimation of Geomagnetically Induced Current. In: Suparta W., Abdullah M., Ismail M. (eds) Space Science and Communication for Sustainability. Springer https://doi.org/10.1007/978-981-10-6574-3_6 15. Yagova, N.V., Heilig, B., Pilipenko, V.A, Yoshikawa A., Nosikova N.S., Yumoto K., and Reda J. (2017), Earth Planets Space 69: 61, https://doi.org/10.1186/s40623-017-0647-x 16. Imajo, S., A. Yoshikawa, T. Uozumi, S. Ohtani, A. Nakamizo, and P. J. Chi (2017), Application of a global magnetospheric‐ionospheric current model for dayside and terminator Pi2 pulsations, J. Geophys. Res. Space Physics, 122, 8589–8603, doi:10.1002/2017JA024246. 17. S.A. Bello, M. Abdullah, N.S.A. Hamid, A. Yoshikawa, A.O. Olawepo (2017), Variations of B0 and B1 with the solar quiet Sq-current system and comparison with IRI-2012 model at Ilorin, Advances in Space Research, Volume 60, Issue 2, 2017, Pages 307-316, ISSN 0273-1177, https://doi.org/10.1016/j.asr.2017.02.003 18. R. A. Marshall, A Kelly, T Van Der Walt, A Honecker, C Ong, D Mikkelsen, A Spierings, G Ivanovich, A Yoshikawa (2017), “Modeling geomagnetic induced currents in Australian power networks,” in Space Weather, vol. 15, no. 7, pp. 895-916, July 2017. doi: 10.1002/2017SW001613 19. D. Baishev, S. Samsonov, A. Moiseev, R. Boroev, A. Stepanov, V.K. Vladi, A. Korsakov, A. Toropov, A. Yoshikawa, K. Yumoto (2017), Monitoring and investigating space weather effects with meridional chain of instruments in Yakutia: a brief overview, Solnechno-Zemnaya Fizika, 3, (2), 27-35. 20. A Moiseev, D Baishev, V Mishin, T Uozumi, A Yoshikawa, A Du (2017), Features of formation of small-scale wave disturbances during a sudden magnetospheric compression, Solnechno-Zemnaya Fizika 3 (2), 36-4421. Hui, D., D. Chakrabarty, R. Sekar, G. D. Reeves, A. Yoshikawa, and K. Shiokawa (2017), Contribution of storm time substorms to the prompt electric field disturbances equatorial ionosphere, J. Geophys. Res. Space Physics, 122, 5568–5578, doi:10.1002/2016JA023754 22. SA Bello, M Abdullah, NSA Hamid, A Yoshikawa, AO Olawepo, Variations of B0 and B1 with the (solar quiet Sq-current system and comparison with IRI-2012 model at Ilorin, Advances in Space Research, 2017, accepted 23. Wang, G. Q., M. Volwerk, T. L. Zhang, D. Schmid, and A. Yoshikawa (2017), High-latitude Pi2 pulsations associated with kink-like neutral sheet oscillations, J. Geophys. Res. Space Physics, 122, 2889–2899, doi:10.1002/2016JA023370. 24. Nurul Shazana Abdul Hamid, Wan Nur Izzaty Ismail and Akimasa Yoshikawa, Latitudinal Variation of Ionospheric Currents in Southeast Asian Sector, Advanced Science Letters 23(3):1444-1447 · February 2017, DOI: 10.1166/asl.2017.8358. 25. Nurul Shazana Abdul Hamid, Wan Nur Izzaty Ismail and Akimasa Yoshikawa , Longitudinal Profile of the Equatorial Electrojet Current and Its Dependence on Solar Activity, Advanced Science Letters 23(2):1357–1360 · February 2017, DOI: 10.1166/asl.2017.8372. 26. MO XiaoHua, ZHANG, DongHe, Larisa GONCHARENKO, ZHANG ShunRong, HAO YongQiang, XIAO Zuo, PE JiaZheng, Akimasa YOSHIKAWA, and CHAU HaDuyen, Meridional movement of northern and southern equatorial ionization anomaly crests in the East-Asian sector during 2002–2003 SSW, Science China Earth Science · February 2017, DOI: 10.1007/s11430 27. Yi Zhang, Z. Zeng, L. Yao, Y. Yokota, Y. Kawazoe, and A. Yoshikawa (2017), Skin Effect of Rotating Magnetic Fields in Liquid Bridge, Journal of Magnetics 22(2):333-343, DOI10.4283/JMAG.2017.22.2.333. 28. Rabiu, A. B., Folarin, O. O., Uozumi, T. and Yoshikawa, A. (2016) Simultaneity and Asymmetry in the Occurrence of Counterequatorial Electrojet along African Longitudes, in Ionospheric Space Weather: Longitude and Hemispheric Dependences and Lower Atmosphere Forcing (eds T. Fuller-Rowell, E. Yizengaw, P. H. Doherty and S. Basu), John Wiley & Sons, Inc., Hoboken, NJ, USA. doi: 10.1002/9781118929216.ch2 29. Ohtani, S., and A. Yoshikawa (2016), The initiation of the poleward boundary intensification of auroral emission by fast polar cap flows: A new interpretation based on ionospheric polarization, J. Geophys. Res. Space Physics, 121, doi:10.1002/2016JA023143. (Selected as Editor’s Highlight) 30. Takahashi, K., M. D. Hartinger, D. M. Malaspina, C. W. Smith, K. Koga, H. J. Singer, D. Frühauff, D. G. Baishev, A. V. Moiseev, and A. Yoshikawa (2016), Propagation of ULF waves from the upstream region to the midnight sector of the inner magnetosphere, J. Geophys. Res. Space Physics, 121, 8428–8447, doi:10.1002 31. Imajo S., A. Yoshikawa, T.Uozumi; S. Ohtani, A. N.Sodnomsambuu Demberel, B. M. Shevtsov (2016), Solar terminator effects on middle-to-low latitude Pi2 pulsations, Earth, Planets and Space, 68 (1), 13768 (1), 137. 32. Uozumi, T., A. Yoshikawa, S. Ohtani, S. Imajo, D. G. Baishev, A. V. Moiseev, and K. Yumoto, (2016), Initial deflection of middle-latitude Pi2 pulsations in the premidnight sector: Remote detection of oscillatory upward field-aligned current at substorm onset, J. Geophys. Res. Space Physics, 121, doi:10.1002/2015JA021698 33. Nishimura N., T.Kikuchi; Y.Ebihara, A.Yoshikawa, S.Imajo; W. Li, H. Utada, Evolution of the current system during solar wind pressure pulses based on aurora and magnetometer observations, , Earth, Planets and Space, 68 (1), 144, (2016). 34. Bisoi,OS. K., D. Chakrabarty, P. Janardhan, R. G. Rastogi, A. Yoshikawa, K. Fujiki, M. Tokumaru, and Y. Yan (2016), The prolonged southward IMF-Bz event of 2?4 May 1998: Solar, interplanetary causes and geomagnetic consequences, J. Geophys. Res. Space Physics, 121, 3882-3904, doi:10.1002/2015JA022185. 35. Bolaji, O. S., E. O. Oyeyemi, O. P. Owolabi, Y. Yamazaki, A. B. Rabiu, D. Okoh, A. Fujimoto, C. Amory-Mazaudier, G. K. Seemala, A. Yoshikawa, and O. K. Onanuga, Solar Quiet Current Response in the African Sector Due to a 2009 Sudden Stratospheric Warming Event, J. Geophys. Res. Space Physics, 2016 August 6,doi:10.1002/2016ja022857 36. Tsuda, T., M. Yamamoto, H. Hashiguchi, K. Shiokawa, Y. Ogawa, S. Nozawa, H. Miyaoka, and A. Yoshikawa, A proposal on the study of solar-terrestrial coupling processes with atmospheric radars and ground-based observation network, Radio Sci., 51, doi: 10.1002/2016RS006035, 2016.“ 37. Fujimoto, A., T. Uozumi, S. Abe, H. Matsushita, S. Imajo, J. K.Ishitsuka, and A. Yoshikawa, Long-term EEJ Variations by Using the Improved EE-index, Sun and Geosphere, Vol.11, Issue 1, 2016 38. Moiseev, A.V., D. G. Baishev, V. A. Mullayarov, S. N. Samsonov, T. Uozumi, A. Yoshikawa, K. Koga, and H. Matsumoto (2016), The Development of Compression Long-Period Pulsations on the Recovery Phase of the Magnetic Storm on May 23, 2007, Cosmic Research, 2016, Vol. 54, No. 1, pp. 31-39. 39. Imajo, S., A. Yoshikawa, T. Uozumi, S. Ohtani, A. Nakamizo, R. Marshall, B. M. Shevtsov, V. A. Akulichev, U. Sukhbaatar, A. Liedloff and K. Yumoto (2015), Pi2 pulsations observed around the dawn terminator, J. Geophys. Res. Space Physics, 120, doi:10.1002/2013JA019691. 40. Hori, T., Y. Miyashita, Y. Miyoshi, K. Seki, T. Segawa, Y.-M. Tanaka, K. Keika, M. Shoji, I. Shinohara, K. Shiokawa, Y. Otsuka, S. Abe, A. Yoshikawa, K. Yumoto, Y. Obana, N. Nishitani, A. S. Yukimatu, T. Nagatsuma, M. Kunitake, K. Hosokawa, Y. Ogawa, K. T. Murata, M. Nose, H. Kawano, and T. Sakanoi, CDF data archive and integrated data analysis platform for ERG developed by ERG Science Center (ERG-SC), J. Space Sci. Info. Jpn., vol. 4, JAXA-RR-14-009 (ISSN 1349-1113), 75-89, 2015. 41. Baishev D.G., Moiseyev A.V., Boroyev R.N., Kobyakova S.E., Stepanov A.E., Mandrikova O.V., Solovev I.S., Khomutov S.Yu., Polozov Yu.A., Yoshikawa A., Yumoto K.,Magnetic and ionospheric observations in the Far Eastern region of Russia during the magnetic storm of 5 April 2010, Sun and Geosphere., 2015. - Vol.10, N2 42. BR Kalita, PK Bhuyan, A Yoshikawa, NmF2 and hmF2 measurements at 95° E and 127° E around the EIA northern crest during 2010–2014, Earth, Planets and Space 67 (1), 1-22, 2015 43. Yoshimasa Tanaka, Yasunobu Ogawa, Akira Kadokura, Noora Partamies, Daniel Whiter, Carl-Fredrik Enell, Urban Brändström, Tima Sergienko, Björn Gustavsson, Alexander Kozlovsky, Hiroshi Miyaoka, Akimasa Yoshikawa, Eastward-expanding auroral surges observed in the post-midnight sector during a multiple-onset substorm, Earth, Planets and Space 67 (1), 1 44. Nurul Shazana Abdul Hamid, Huixin Liu, Teiji Uozumi and Akimasa Yoshikawa (2015), Empirical model of equatorial electrojet based on ground-based magnetometer data during solar minimum in fall, Earth, Planets and Space (2015) 67:205 DOI 10.1186/s40623-015-0373-1 45. Ieda, A., S. Oyama, H. Vanhamaki, R.Fujii, A. Nakamizo, O. Amm, T. Hori, M. Takeda, G. Ueno, A. Yoshikawa, R. J. Redmon, W. F. Denig, Y. Kamide and N. Nishitan (2015), Approximate forms of daytime ionospheric conductance, J. Geophys. Res. Space Physics, 119, 10,397–10,415. doi:10.1002/2014JA020665. 46. Wang, G. Q., M. Volwerk, R. Nakamura, P. Boakes, T. L. Zhang, A. Yoshikawa, and D. G. Baishev (2015), Flapping current sheet with superposed waves seen in space and on the ground, J. Geophys. Res. Space Physics, 119, 0,078–10,091. doi:10.1002/2014JA020526. 47. O.S. Bolaji, A.B. Rabiu, O.R. Bello, A. Yoshikawa, K. Yumoto, O.O. Odeyemi and O. Ogunmodimu (2015), Spatial Variability of Solar Quiet Fields Along 960 Magnetic Meridian in Africa: Results from Magdas, J. Geophys. Res. Space Physics, Accepted manuscript online: 26 MAR 2015, DOI: 10.1002/2014JA020728 48. Takla, E. M., H. Odah, E. M. Abd Elaal, A. Yoshikawa, H. Kawano, T. Uozumi, (2015), The 2011 Eruption of Aso Volcano in Japan and its Signature on the Geomagnetic Field Measurements, Arabian Journal of Geosciences, DOI 10.1007/s12517-015-1858-8. 49. OS Bolaji, EO Oyeyemi, PR Fagundes, AJ de Abreu, R de Jesus, and A. Yoshikawa (2015), Counter Electrojet Events using Ilorin Observations during a Low Solar Activity Period, 2015, The African Review of Physics 9. 50. Liu, J., L. Liu, T. Nakamura, B. Zhao, B. Ning, and A. Yoshikawa (2014), A case study of ionospheric storm effects during long-lasting southward IMF Bz-driven geomagnetic storm, J. Geophys. Res. Space Physics, 119, 7716–7731, doi:10.1002/2014JA020273. 51. Teramoto, M., N. Nishitani, V. Pilipenko, T. Ogawa, K. Shiokawa, T. Nagatsuma, A. Yoshikawa, D. Baishev, and K. T. Murata (2014), Pi2 pulsation simultaneously observed in the E and F region ionosphere with the SuperDARN Hokkaido radar, J. Geophys. Res. Space Physics, 119, 3444–3462, doi:10.1002/2012JA018585 52. F Cuturrufo, V Pilipenko, B Heilig, M Stepanova, H Lühr, P Vega and A. Yoshikawa (2014), Near-equatorial Pi2 and Pc3 waves observed by CHAMP and on SAMBA/MAGDAS stations, Advances in Space Research 11/2014; DOI:10.1016/j.asr.2014.11.010 53. Yamazaki, Y., A. D. Richmond, A. Maute, Q. Wu, D. A. Ortland, A. Yoshikawa, I. A. Adimula, B. Rabiu, M. Kunitake, and T. Tsugawa (2014), Ground magnetic effects of the equatorial electrojet simulated by the TIE-GCM driven by TIMED satellite data, J. Geophys. Res. Space Physics, 119, 3150–3161, doi:10.1002/2013JA019487 54. Takla, E.M., A. Yoshikawa, H. Kawano, T. Uozumi, S. Abe (2014) Anomalous Geomagnetic Variations Associated with the Volcanic Activity of the Mayon Volcano, Philippines during 2009-2010, NRIAG Journal of Astronomy and Geophysics, DOI 10.1016/j.nrjag.2014.09.001. 55. Cardinal, M. G., A. Yoshikawa, H. Kawano, H. Liu, M. Watanabe, S. Abe, T. Uozumi, G. Maeda, T. Hada, and K. Yumoto (2014), Capacity Building: A Tool for Advancing Space Weather Science, Space Weather, 12, 571–576, doi:10.1002/2014SW001110. 56. Imajo S., K.Yumoto, T.Uozumi, H.Kawano, S.Abe, A.Ikeda, K.Koga, H. Matsumoto, T.Obara, R.Marshall, V.A. Akulichev, A. Mahrous, .Liedloff, and A.Yoshikawa (2014), Analysis of propagation delays of compressional Pi 2 waves between geosynchronous altitude and low latitudes, Earth, Planets and Space, 66:20 (24 April 2014 57. Nurul Shazana Abdul Hamid, Huixin Liu, Teiji Uozumi, Kiyohumi Yumoto, Bhaskara Veenadhari, Akimasa Yoshikawa, Jairo Avendaño Sanchez (2014), Relationship between the Equatorial Electrojet and Global Sq Currents at the Dip Equator Region, Earth, Planets and Space 2014, 66:146, doi:10.1186/s40623-014-0146 58. Yoshikawa A., M.G. Cardinal, T. Hada and K. Yumoto (2013), MAGDAS Capacity Building Activities for Space Weather Research at ICSWSE, Research Note, Space Research Today, Volume 188, December 2013, Pages 18-20, ISSN 1752-9298, http://dx.doi.org/10.1016/j.srt.2013.11.007 59. Yoshikawa, A., O. Amm, H. Vanhamäki, A. Nakamizo, and R. Fujii (2013), Theory of Cowling channel formation by reflection of shear Alfven waves from the auroral ionosphere, J. Geophys. Res. Space Physics, 118, doi:10.1002/jgra.50514. 60. Yoshikawa, A., O. Amm, H. Vanhamäki, and R. Fujii (2013), Illustration of Cowling channel coupling to the shear Alfven wave, J. Geophys. Res. Space Physics, 118, doi:10.1002/jgra.50513. 61. Shi, R., H. Liu, A. Yoshikawa, B. Zhang, and B. Ni (2013), Coupling of electrons and inertial Alfven waves in the topside ionosphere, J. Geophys. Res. Space Physics, 118, 2903–2910, doi:10.1002/jgra.50355. 62. Ohtani, S., T. Uozumi, H. Kawano, A. Yoshikawa, H. Utada, T. Nagatsuma, and K. Yumoto (2013), The response of the dayside equatorial electrojet to step-like changes of IMF BZ, J. Geophys. Res. Space Physics, 118, 3637–3646, doi:10.1002/jgra.50318. 63. Amm, O., R. Fujii, H. Vanhamäki, A. Yoshikawa, and A. Ieda (2013), General solution for calculating polarization electric fields in the auroral ionosphere and application examples, J. Geophys. Res. Space Physics, 118, 2428–2437, doi:10.1002/jgra.50254. 64. A Fujimoto, A Yoshikawa, A Ikeda (2018), Global response of Magnetic field and Ionosonde observations to intense solar flares on 6 and 10 September 2017 - E3S Web of Conferences, 2018 65. A Ikeda, T Uozumi, A Yoshikawa, A Fujimoto, S Abe (2018), Schumann resonance parameters at Kuju station during solar flares- E3S Web of Conferences, 2018 66. M Nakahara, A Yoshikawa, T Uozumi, A Fujimoto, Electromagnetic induction responses to geomagnetic disturbances at low-and-mid-latitudes,Journal of Physics: Conference Series 1152 (1), 0120352019. 67. T Akiyama, A Yoshikawa, A Fujimoto, T Uozumi, Relationship between plasma bubble and ionospheric current, equatorial electrojet, and equatorial counter electrojet, Journal of Physics: Conference Series 1152 (1), 0120222019. 68. ZIA Latiff, MH Jusoh, FAM Kasran, SAE Ab Rahim, M Onn, A Zainuddin, and A. Yoshikawa, The first solar-powered Magdas-9 installation and possible geomagnetically induced currents study at Johor, Malaysia, Journal of Physics: Conference Series 1152 (1), 0120302019. 69. SN Ibrahim, MH Jusoh, AA Sulaiman, A Yoshikawa, ZM Radzi, Characteristic of the Disturbed Days Ionospheric Current System in the 180-Degree Magnetic Meridian, Journal of Physics: Conference Series 1152 (1), 0120292019. 70. NM Anuar, FAM Kasran, M Abbas, MH Jusoh, SAE Ab Rahim, N Abdul Hadi, A Yoshikawa, Z Mohd Radzi，Assessment of the Geomagnetically Induced Current (GIC) at Low Latitude Region based on MAGDAS Data, Journal of Physics: Conference Series 1152 (1), 0120282019. 71. N.N. Anuar, FAM Kasran, ZIA Latif, SAE Ab Rahim, A Manut, MH Jusoh, N. A. Hadi, A. Yoshikawa, Estimation of Time Derivative of Horizontal Geomagnetic Component for GIC Assessment in Malaysia during Quiet Period, 2018 IEEE 8th International Conference on System Engineering and Technology (ICSET),118 72. K Terada, C Tao, N Terada, Y Kasaba, H Kita, A Nakamizo, A Yoshikawa, Study of the Solar Wind Influence on the Jovian Inner Magnetosphere Using an Ionospheric Potential Solver, Lunar and Planetary Science Conference 49, 2018. 73. Yoshikawa A., A Fujimoto, A Ikeda, T Uozumi, S Abe (2017), Monitoring of Space and Earth electromagnetic environment by MAGDAS project: Collaboration with IKIR-Introduction to ICSWSE/MAGDAS project, E3S Web of Conferences 20, 01013 (2017), DOI: 10.1051/e3sconf/20172001013, Solar-Terrestrial Relation 74. Akihiro Ikeda, Teiji Uozumi, Akimasa Yoshikawa, Akiko Fujimoto, Shuji Abe, Hiromasa Nozawa, Manabu Shinohara、Akihiro Ikeda, Teiji Uozumi, Akimasa Yoshikawa, Akiko Fujimoto, Shuji Abe, Hiromasa Nozawa, Manabu Shinohara, Characteristics of Schumann Resonance Parameters at Kuju Station, E3S Web of Conferences 20, 01004 (2017), DOI: 10.10 Terrestrial Relations and Physics of Earthquake Precursor 75. W N I Ismail , N S A Hamid, M Abdullah, A Yoshikawa and T Uozumi (2017), Longitudinal Variation of EEJ Current during Different Phases of Solar Cycle, J. Phys.: Conf. Ser. 852 012019 76. N S A Hamid, H Liu, T Uozumi3, A Yoshikawa and N M N Annadurai (2017) Peak time of equatorial electrojet from different longitude sectors during fall solar minimum , J. Phys.: Conf. Ser. 852 012015 77. Nurul Shazana Abdul Hamid, Huixin Liu, Hanifa Ab Hadin, Teiji Uozumi, Geri Kibe Gopir and, Akimasa Yoshikawa, (2015) Longitudinal and Solar Activity Dependence of Equatorial electrojet at Southeast Asian sector, accepted to proceedings of 2015 IEEE International Conference on Space Science & Communication (IconSpace2015 78. NSA Hamid, MH Jusoh, FAM Kasran, M Abdullah, B Veenadhari, T Uozumi, S Abe, A Yoshikawa, MG Cardinal, Variations of ULF and VLF during moderate geomagnetic storm at equatorial region, IEEE, IconSpace, 256-261, 201 79. NSA Hamid, H Liu, T Uozumi, GK Gopir, HA Hadin, A Yoshikawa, Longitudinal and solar activity dependence of equatorial electrojet at Southeast Asian sector, IEEE, IconSpace,262-266, 2015 80. Sit Niir Aisyah Ahmad, Mohamad Huzaimy Jusoh, Mohd Shariff, Khairul Khaizi, Mardina Abdullah, Mhd Fairos Asillam, B Veenadhari, T Uozumi, S Abe, A Yoshikawa, MG Cardinal (2014), Data Processing Method to classify Pc5 ULF Pulsations due to Solar Wind Perturbations at Equatorial region, ISSN ⁄ E-ISSN: 1790 2019/Mar/25 AGS 2019@Cairo, Egypt

MAGDAS database and data http://search.iugont.org/

MAGDAS information and plot via us (http://data.icswse.kyushu-u.ac.jp/) IUGONET Type-A (see right). MAGDAS data via us, SPEDAS (Space Physics Environment Data Analysis System, http://spedas.org/wiki/index.php), ERG-SC (https://ergsc.isee.nagoya-u.ac.jp/data_info/ground.shtml.en), and SuperMAG (http://supermag.jhuapl.edu/) in near future.

Realtime data is not registered. If you want to use them, please contact us

33 2019/Mar/25 AGS 2019@Cairo, Egypt

Inter-university About IUGONET Upper atmosphere Global Observation NETwork

http://www.iugonet.org/index.jsp?lang=en

Ø Develop a metadata database ground-based upper atmosphere observation data. Ø Promote effective use of the observational data spread across the institutes/universities. Ø Investigate mechanism of long-term variation in the upper atmosphere.

34 Summary

・Introduce MAGDAS project and related science

・Research for coupling between atmospheric dynamics and plasma dynamics, and its lithospheric electromagnetic responses will break ground a new area of science

・We strongly hope realization of Equatorial ionospheric HF radar network presented by Dr. R. Todd Parris, and development of SuperDARN covering much more lower and equatorial region

Thank you for your attention!!