Japan-Indonesia collaborative study of equatorial atmosphere~ 20 years of the Equatorial Atmosphere Radar and beyond ~Research Institute for Sustainable Humanosphere (RISH),
Kyoto University, Japan
Research Organization of Aeronautics and Space (LAPAN),
National Research and Innovation Agency (BRIN), Indonesia

Contents

1. Introduction .............................................................................................................. 1
2. Equatorial Atmosphere Radar (EAR) ..................................................................... 2
3. Research Project “Study of Coupling Processes in the Solar-Terrestrial System” ... 5
4. Equatorial Fountain .................................................................................................. 7
5. The Equatorial Middle and Upper Atmosphere (EMU) Radar................................. 8
6. Global Observation Network and the EMU Radar................................................... 11
7. Data Exchange System ............................................................................................. 12
8. Capacity Building ..................................................................................................... 13
9. Summary and Conclusion ........................................................................................ 13
References .................................................................................................................... 14

1. Introduction
The western Pacific region called the Indonesian Archipelago is the center of the intense atmosphericmotions and global atmospheric changes. However, the mechanisms of the atmospheric changes andfluctuations were not clear due to the sparseness of observation data in that region. Research Institute for
Sustainable Humanosphere (RISH), Kyoto University, Japan and Research Organization of Aeronautics andSpace (LAPAN), National Research and Innovation Agency (BRIN), Indonesia started scientific collaborationin the middle 1980 to overcome this problem. Table 1 shows list of historical events during 35 years of thiscollaboration. The first contact from RISH (the institute name at the time was “Radio Atmospheric Science
Center (RASC)”) was a plan of “Equatorial Radar” that was the gigantic radar planned right over the
Table 1: History of scientific collaboration between RISH and LAPAN
1986 First visit to LAPAN observatories in Pontianak (west Kalimantan) and Biak (Irian Jaya)
1987 Intensive site survey for “Equatorial Radar” project (Pontianak and west Sumatra)
1990 Campaign observations with balloon-borne radiosondes at the LAPAN observatory in Watukosek, east
Jawa
1992 Establishment of a radar observatory in PUSPIPTEK, Serpong, west Jawa (Meteor Wind Radar andBoundary Layer Radar)
1992- Radiosonde campaigns in LAPAN observatories (Bandung, PUSPIPTEK, Pontianak, etc.)
1995 Establishment of an MF radar observatory in Pontianak
2001 Establishment of the Equatorial Atmosphere Radar (EAR) in Kototabang, West Sumatra
FY2001-2006 Grant-in-Aid for Scientific Research on Priority Areas “Coupling Processes in the Equatorial
Atmosphere (CPEA)” led by Prof. S. Fukao
FY2008-2010 JSPS Asia-Africa Science Platform Program “Elucidation of ground-based atmosphereobservation network in equatorial Asia” led by Prof. T. Tsuda
FY2010-2012 Strategic Fund for Promotion of Science and Technology “Research enhancement and systemdevelopment for space weather in Indonesia” led by Prof. M. Yamamoto2011 10th anniversary of the EAR at RISTEK, Jakarta
2013 Research project “Study of coupling processes in the solar-terrestrial system” (leader: Prof. T. Tsuda)
was proposed to Japan Science Council, and was approved as one of important projects in Master Plan
2014.
2014 The project included as one of 11 new projects in Roadmap 2014 of Japanese Minister of Education,
Culture, Sports, Science, and Technology (MEXT).
2014 RISH and LAPAN signed Letter of Intent for the new project of the Equatorial MU (EMU) radar that isincluded in the big project.
2016 15th anniversary of the EAR at Sari Pan Pacific Hotel, Jakarta
FY2016-2021 RISH “Humanosphere Asia Research Node”
2017 Research project was approved as an important project in Master Plan 2017.
2017 15th International Workshop on Technical and Scientific Aspects of MST Radar at Tokyo
2018 International Conference on Tropical Meteorology and Atmospheric Sciences (ICTMAS) at Bandung2019 International School on Equatorial Atmosphere (ISQUAR) at Bandung2020 Research project was approved as an important project in Master Plan 2020.
2021 20th anniversary of the EAR (online)1

geographic equator. We pursued the plan with intensive site survey for the facility. Meanwhile in 1990, we
conducted the first observation campaign of the equatorial atmosphere by using radiosondes. Then we started
installation of two compact radars in 1992 at PUSPIPTEK, and a Middle-Frequency (MF) radar in 1995 at
Pontianak. During the course of these research efforts, we reached the construction of the Equatorial
Atmosphere Radar (EAR). Collaborative study between RISH and LAPAN was very much enhanced by the
EAR together with timely research project “Coupling Processes in the Equatorial Atmosphere” (2001-2007
led by Prof. S. Fukao). The EAR was successfully operated under this collaboration. We conducted the 10thand 15th anniversary of the EAR in 2011 and 2016, respectively, in Jakarta. This document summarizes thislong-time scientific collaboration between Japan and Indonesia. We also discuss future direction centeredaround the new facility Equatorial Middle and Upper atmosphere (EMU) radar.
2. Equatorial Atmosphere Radar (EAR)
The mechanisms which cause atmospheric variability in the western Pacific region are considered to havehierarchical and multiple structures, which require us to observe the atmosphere with various scales. As a key
facility for these studies, we built the EAR at the Equatorial Atmosphere Observatory, Kototabang, West
Sumatra, Indonesia (0.20°S, 100.32°E) in 2001 [Fukao et al., 2003]. Figure 1 shows the antenna field of the
EAR and its location. The operation of the EAR is based upon the memorandum of understanding (MOU)
between RISH and LAPAN.
The EAR is an atmospheric radar operated at 47-MHz center frequency. Table 2 lists the specifications of
the EAR. A peak output power is 100 kW. The EAR has a circular active phased antenna which consists of
560 three-element Yagi antennas. As shown in Figure 1, each Yagi antenna is driven by a solid-state

Figure 1: Overview of EAR (top) with configuration of each Yagi antenna (bottom right) and location of theEAR site (bottom left).
2

transmitter/receiver module with a peak output power of 180 W. Owing to the active phased array antenna, theEAR can electronically change beam directions with a rate up to 5,000 times per second. The EAR is designed
to measure vertical and horizontal wind velocities and turbulence in the troposphere and the lower
stratosphere (up to 20 km altitude) with high time and height resolutions (less than 1 minute and 150 m,
respectively). The EAR is also able to observe ionospheric irregularities such as plasma bubbles above
approximately 90 km altitude. The EAR started the continuous observations of the equatorial atmosphere inJune 2001. As shown in Figure 2, it provides us with valuable database for the Earth’s environmental research.
Since the establishment of the EAR, many instruments have been installed in the radar site throughcollaborations with other research institutes as shown in Figure 3, such as Rayleigh and sodium lidars,
FM-CM ionosonde, VHF radar, meteor radar, X-band meteorological radar, all-sky imager, Fabry-Perot
interferometer, micro-rain radar, ceilometer, disdrometer, optical rain gauge, radiometer, and GPS receivers.
The EAR can observe gravity wave behaviors, turbulence generation, and wind motions in the troposphereand the lower stratosphere. One of the major achievements from the EAR is finding of Kelvin-wave
modulation of the tropopause region [Fujiwara et al., 2003], which provided direct evidence that mixing ofstratospheric air and tropospheric air occurred by the Kelvin wave breaking. Also, high-resolution wind andturbulence measurements by the EAR greatly contributed to clarify the generation mechanisms of deep
cumulus convection that further excites atmospheric gravity waves [e.g., Ratnam et al., 2006]. From theionosphere observations, the pulse-to-pulse antenna beam-scan measurement by the EAR revealed the spatial
evolution of equatorial plasma bubbles, which propagate and affect electromagnetic phenomena in theequatorial thermosphere [e.g., Fukao et al., 2004].
Table 2: Specifications of the EAR
Location

0.20°S, 100.32°E

Frequency

47.0 MHz

Output power

100 kW (Peak envelope)

Antenna system

Quasi-circular active phased array(110 m diameter, 560 three-element Yagis)

Beam width

3.4° (half-power, one-way)

Beam direction

Anywhere (within 30° zenith angle)

3

Figure 2: Operation period of the EAR since June 2001. Gray rectangles are the period of the troposphere andlower stratosphere measurements (hereafter ST measurement). Black rectangles are the periods that
ionosphere and ST measurements were carried out simultaneously.

Figure 3: Equipment installed at the Equatorial Atmosphere Observatory. (1: FM-CW ionosonde, 2: VHF
radar, 3: Meteor radar, 4: X-band meteorological radar, 5: RASS speakers, 6: All-sky imager, 7: Fabry-Perot
interferometer, 8: Micro-rain radar, 9: Ceilometer, 10: Disdrometer, 11: Optical rain gauge, 12: Radiometer,
13: GPS receiver, 14: Lidar)
43. Research Project “Study of Coupling Processes in the Solar-Terrestrial System”
The solar energy can mainly be divided into two categories; the solar radiation, and the solar wind. The
former maximizes at the equator, generating various disturbances over a wide height range, causing vertical
coupling processes of the atmosphere between the troposphere and middle and upper atmospheres by upward
propagating atmospheric waves. The energy and material flows that occur in all height regions of theequatorial atmosphere are named as “Equatorial Fountain”. These processes from the bottom also cause
various space weather effects, such as satellite communication and GNSS positioning. While, theelectro-magnetic energy and high-energy plasma particles in the solar wind converge into the polar region
through geomagnetic fields. These energy/particle inflow results in auroral Joule heating and ion drag of theatmosphere particularly during geomagnetic storms and substorms.
The study of these coupling processes in the solar-terrestrial physics (STP) has been internationallyorganized by the Scientific Committee on Solar-Terrestrial Physics (SCOSTEP) under the International
Science Council (ISC; former International Council for Science (ICSU)). Since the International GeophysicalYear (IGY) in 1957, many international research programs of about five year long have been continuously
conducted. Recently, Climate and Weather of the Sun-Earth System (CAWSES) was conducted during
2004-2013 [Tsuda et al., 2015]. Variability of the Sun and Its Terrestrial Impact (VarSITI) was conductedduring 2014-2018 (http://www.varsiti.org/). Now the new project Predictability of the Variable
Solar-Terrestrial Coupling (PRESTO) is running in 2019-2024 by SCOSTEP (https://scostep.org/presto/).
We propose the research project “Study of coupling processes in the solar-terrestrial system” to clarify theseoverall coupling processes in the solar-terrestrial system from the bottom and from above through highresolution observations at key latitudes in the equator and in the polar region. In this project we will establish
a large radar with active phased array antenna, called the Equatorial Middle and Upper atmosphere (EMU)
radar, in west Sumatra, Indonesia. We will participate in construction of the EISCAT_3D radar in northern
Scandinavia, too. These radars will enhance the existing international radar network. We also develop a global
observation network of compact radio and optical remote-sensing equipment from the equator to polar region.
Our proposal is widely supported by national and international scientific communities. Table 3 lists
scientific communities and institutions that are related to our proposal. The development of the EMU radar
has gained full support from the Indonesian Government, similar to the EISCAT_3D project that progressedwith international discussions with European countries and China. In Japan, this project is formally supported.
It has been selected as one of important projects in the Master Plan 2014/2017/2020 that was endorsed by theJapan Science Council (http://www.scj.go.jp/ja/info/kohyo/pdf/kohyo-24-t286-1.pdf).

5

Table 3: List of related scientific community and research organizations
Japan:JpGU (Japan Geoscience Union) Section for Space and Planetary Sciences,
SGEPSS (Society of Geomagnetism, Earth, Planetary and Space Sciences),
Meteorological Society of Japan,
IEICE (The Institute of Electronics, Information and Communication Engineers),
International:
ISC/SCOSTEP (Scientific Committee on Solar-Terrestrial Physics)
ISC/URSI (International Radio Science Union),
ISC/IUGG (International Union on Geodesy and Geophysics),
Science steering group (SSG) for the MST radar workshop,
ISWI (International Space Weather Initiative)
IEEE Milestone for the MU radar (May, 2015)
Indonesia:

BRIN (National Research and Innovation Agency)
BAPPENAS (National Development Planning/National Development Planning Agency)
BMKG (Indonesian Agency for Meteorology, Climatology and Geophysics),
ITB (Bandung Institute of Technology), etc.
EISCAT scientific association
Established in 1975 by FRG (Federal Republic of Germany), UK, France, Norway, Sweden, andFinland.
Japan and China joined in 1996 and 2007, respectively.

6

4. Equatorial Fountain
Cumulonimbus convection is active in the equatorial atmosphere. It generates various types of atmosphericwaves that propagate upward to transport energy and momentum into the upper atmosphere including theionosphere [e.g., Tsuda, 2014]. Also, different kinds of materials (atmospheric minor constituents) originating
at low- and mid-latitude regions and converging into the equatorial region are blown upward through thetropopause. They eventually reach the middle atmosphere and spread to the whole globe. In the upper
atmosphere, there are plasma disturbances, and the equatorial ionization anomaly (EIA) is generated aroundthe geomagnetic equator [e.g., Appleton, 1946; Balan and Bailey, 1995; Rishbeth, 2000; Lin et al., 2007]. Theenergy and material flows that occur in all height regions of the equatorial atmosphere are named as“Equatorial Fountain”. Figure 4 shows the conceptual diagram of the Equatorial Fountain. In our new research
project “Study of Coupling Processes in the Solar-Terrestrial System”, we propose to develop EMU radar
which is a new radar with transmitting power 10 times larger than the existing EAR. The high sensitivity of
the EMU radar will enable the measurement of winds in the troposphere, middle atmosphere andthermosphere/ionosphere. Using the EMU radar we will discover and clarify unknown phenomena of theEquatorial Fountain in wide range of altitudes, focusing on the following three major scientific subjects:
Material fountain: Different kinds of materials in the atmosphere are emitted from land- and sea-surface inthe equatorial region. They contribute to the generation of cumulus and/or cirrus clouds while circulatingin the troposphere. The materials flow into the stratosphere through the tropopause like a fountain, andreach widely to the middle and high latitude regions.
Energy fountain: Atmospheric waves
originatingintransfer

their

the

troposphereenergyandmomentum like a fountain up to
the middle atmosphere, where
peculiarlong-term

waves

and

irregularities are induced.
Plasma fountain: The ionosphericplasma around the geomagnetic
equator is blown upward by the
dynamo electric field induced by
the background neutral winds,
which is known as plasma fountain.
A variety of energy exchange andplasma-density

fluctuations

inducedthroughthebetweenthedynamics

arecoupling
andelectromagnetics.
Figure 4: Phenomena in the equatorial atmosphere.
75. The Equatorial Middle and Upper Atmosphere (EMU) Radar
We developed the MU radar in Japan, which is the first application of active phased array antenna toatmospheric radars, and extended it to similar radar systems in oversea facilities. This technical innovation has
been adopted by foreign research groups for the development of other radars. The MU radar was selected asIEEE Milestone which honors significant technical achievements in all areas associated with IEEE (TheInstitute of Electrical and Electronics Engineers). Based on this heritage, the state-of-the-art techniques
established by the MU radar will be used for the EMU radar.
The EMU radar, a large-aperture Doppler radar operating at 47 MHz, will be installed at the north side of
the EAR at Kototabang in West Sumatra, Indonesia. The specifications of the radar are given in Table 4. The
antenna system and the system block diagram of the EMU radar is shown in Figures 5 and 6, respectively. The
antenna is an active phased array consisting of 1045 three-element crossed Yagi antennas. Each of the 1045
antennas is equipped with a solid-state transmitter-receiver (TR) module with 500 W (peak envelope power;
PEP) output, so the total output power is about 500 kW (PEP). The antenna beam can be steered electricallyon a pulse-to-pulse basis by controlling phase shifters in the TR modules. The large antenna array of 160-m
diameter and 500 kW (PEP) output enables the EMU radar to have 10-times higher sensitivity than the EAR
and comparable sensitivity to that of the MU radar. The transmitted pulse length is variable but has aminimum length of 0.5 μs, corresponding to a height resolution of 75 m. In order to increase sensitivity, binary
phase codes, such as Barker and complementary codes [e.g., Schmidt et al., 1979], are utilized for pulse
compression techniques. Spano codes [Spano and Ghebrebrhan, 1996], which are an extension ofcomplementary codes, are also applicable.
The Yagi antennas are located on grids of equilateral triangles with a side that is 4.5 m (approximately 0.7
wavelength) long as shown in Figure 5. For this element spacing, no grating lobe is formed at beam positions
within 30 deg. around the zenith. For radar imaging measurements [Palmer et al., 1998], the 1045 Yagi
elements can be divided into 55 sub-arrays, each of which is composed of 19 Yagi elements and an identicalnumber of TR modules. In-house equipment consists of a multi-channel signal processer system with a digitalmodulator/demodulator unit and a host computer which is a Linux-based personal computer. A maximum of
five frequencies can be chosen between 46.5 MHz and 47.5 MHz in steps of 1 kHz for range imaging
measurements [Luce et al., 2001]. The EMU radar will be operated under close collaboration with LAPAN
following the success of the EAR experiment since 2001.
In the radar site there are many other measurement instruments as shown in Figure 3. Various observation
techniques from these instruments are very useful to obtain various atmospheric parameters, complementing
the results with EMU. The coordinated observations using the EMU radar and these collocated instruments are
expected to clarify dynamics, photo-chemistry and electro-dynamics occurring in the equatorial atmosphere.
In particular, Radio Acoustic Sounding System (RASS) [Tsuda et al., 1994] was adopted to EAR for obtaining
atmospheric temperature in the troposphere up to about 10 km [Alexander et al., 2006; Ina et al., 2018]. By
applying RASS to the EMU radar, having 10 times more sensitive compared to EAR, we will be able to raise
the maximum altitude of temperature profiles as high as 23 km [Matuura et al., 1986; Sarma et al, 2008]. Then,8we can continuously observe temperature variations in the upper troposphere and lower stratosphere (UTLS)
region, including the tropical tropopause. For the study of the middle and upper atmosphere, we have beensuccessful on EAR observations of ionospheric irregularities like plasma bubble. The EAR’s pulse-to-pulse
beam steering capability enabled us to reveal separately the time-spatial structures of plasma bubbles [e.g.,
Fukao et al, 2004; Fukao et al, 2006]. The new EMU radar system will add three more capabilities; 1)
mesosphere experiment with turbulent echoes at the height region of 60-90 km, 2) incoherent scatter (IS)experiment, and 3) radar imaging experiment. 1) and 2) is possible from higher sensitivity and circularpolarization of the EMU radar. 3) is based on the spatial interferometry with 55-channel receiver system. The
IS experiment should be first over the Asian sector with the active phased-array radar, and we can obtain
information of the background ionosphere. The radar imaging, on the other hand, will give us more detailed
information of the ionospheric irregularities while larger structures are observed by the multi-beamexperiment.
The use of the EMU radar will be open to the international community through international collaborative
research programs. The EMU radar will also be utilized for education of young scientists from all over theworld.
Table 4: Specifications of the Equatorial MU (EMU) radar system
EMU System Parameter

Value

Antenna Specifications
Antenna type

Crossed Yagi antennas

Configuration

Quasi-circular array of diameter 160 m

Aperture

About 16,000 m2

Full antenna beam width

2.4 deg. (one-way half-power full width)

Function

Electronic beam steering pulse to pulse

Beam directions

Arbitrary direction within a zenith angle of 30 deg.

Polarization

Circular polarization

Transmit System
Configuration

1045 solid-state TR modules

Maximum peak output power

500 kW

Maximum duty ratio

10%

Operating center frequency

47.0 MHz

Pulse resolution

75 m (min.)Receive System
Allocated bandwidth

6 MHz

Receiver channels

55+9 channels of synchronous quadratic detection

Pulse compression

Barker, complementary, and Spano codes9Figure 5: The EMU radar antenna array. Each cross represents the location of a three-element Yagi antenna
and TR module.

Figure 6: Schematic diagram of the EMU radar.

106. Global Observation Network and the EMU Radar
Figure 7 shows global distribution of IS and MST radars. The IS radar has a long history of more than 50
years [Robinson et al., 2009; Altschuler and Salter, 2013]. Arecibo and Jicamarca radars were constructed as
constant facility for the IS experiment in early 1960s. Then development of the MST radar followed[VanZandt, 2000]. The EISCAT radar started multi-static IS observations in 1981 [Schlegel and Moorcroft,1989]. The MU radar was the first MST radar with the active phased-array which most recent radars are using[IEEE Milestone for the MU radar, 2015]. It is very clear that the current solar-terrestrial physics is developed,
on many aspects, based on countless results from their observations [e.g., Kelley, 2009; Fukao and Hamazu,2013]. The EMU and the EISCAT_3D
radars that we propose from our project
should help expansion of the science.
These two radars will further promoteinternational collaboration of the IS
and MST radars complementing theexisting facilities, such as Resolute
Bay (74.7N, 94.9W), Sondrestrom(67.0N, 50.9W), Poker Flat (65.1N,
147.5W),

Millstone

Hill(42.6N,

71.5W), the MU radar (34.9N, 136.1E),
Arecibo (18.3N, 66.8W),

Gadanki

MST radar (13.5N, 79.2E), Jicamarca(12.0S, 76.9W) and PANSY (69.0S,
39.6E).

Figure 7: Map of the possible sites for the global observation network.

The EMU radar should work with this global observation network of the IS and MST radars. In particularwith the MU radar (in Japan, mid-latitude region), PANSY [Sato et al., 2014] and EISCAT_3D radar (in polar
region) are important, and contribute to the study of the coupling processes in the solar-terrestrial system.
Help from the regional network observations is also important for our studies. In the southeast Asian region,
we already have observation network of ionosondes, meteor and MF radars, airglow imagers, magnetometers,
etc. EAR was already successful on collaboration with Indian MST radar or Sanya radar in China [e.g., Patra
et al, 2008; Li et al., 2013]. Observation network in the Asian sector is now rapidly growing. For example, IS
experiment recently started at Quijing, China (25.6N, 103.8E, [Ding et al., 2014]), which research activity
seems limited but close to the geomagnetic conjugate to our EMU/EAR site. We can anticipate fruitful studies
between the EMU radar and these regional and global network of instruments.
During the planned period of this project, several scientific satellite missions are launched, such as
Exploration energization and Radiation in Geospace (ERG) (http://ergsc.stelab.nagoya-u.ac.jp/index.shtml.en)[Miyoshi et al., 2012], Ionosphere Connection Explorer (ICON) (http://dev.icon.ssl.berkeley.edu/) [Rider et al.,2015],

andConstellation

Observing

Systemfor

Meteorology,(FORMOSAT-7/COSMIC-2) (http://www.cosmic.ucar.edu/cosmic2).
11

IonosphereandClimate2

7. Data Exchange System
Effective database construction is also an essential part to make such a comprehensive network observation
available. Our group has constructed ground-based observation database under the project “Inter-university
Upper atmosphere Global Observation NETwork (IUGONET)” since 2009 [Hayashi et al., 2013]. The conceptof the IUGONET is illustrated in Figure 8. The IUGONET project has archived metadata of various
ground-based observation instruments operated by five Japanese institutions, i.e., Tohoku University, National
Institute of Polar Research, Nagoya University, Kyoto University, and Kyushu University. Under the
IUGONET project, huge amount of various dataset obtained by these institutions are recorded into the
database, and their metadata (catalogue information) can be searched on the web. Comprehensive data
analysis using different types of data becomes possible by using this database [Abe et al., 2014]. A unified
data analysis tool, called IUGONET data analysis software (UDAS) [Tanaka et al., 2013], was also developed
to make plots of the real data in the database. Such a construction of metadata database with unified data
analysis tool is essential for the proposed mission of global network observations, in order to make use of theadvantage of the network observation and to expand the scientific use of the data. The unified data analysis
tool also encourages the data analysis for scientists at developing countries and students who are not familiar
to the different types of data handling [Hayashi et al., 2013].
RISH accumulates various data from our studies, and form them as Humanosphere database. The data arebasically open to the research community. We now plan to make a backup site in Indonesia to hold the copy ofall data in safe. The copy database system will be open to the Indonesian research community, and will be
helpful for future expansion of science in Indonesia.

Figure 8: Schematic view of the virtual information center of the IUGONET project. A metadata database isdistributed at the IUGONET institutes, as shown with boxes labeled “XML”, and connected to other metadata
databases through the Internet in order to share all the metadata. In addition, data analysis software to handle
various kinds of solar-terrestrial environment observation data is developed (Modified from Hayashi et al[2013]).
12

8. Capacity Building
Collaboration between RISH and LAPAN has been very successful in terms of education and capacity
building. All Ph.D. degrees obtained based on the EAR-related studies is 20, which includes 7 Ph.D. degrees
obtained by 6 Indonesian and 1 Vietnam students. Number of master degrees is 49 that include 6 Indonesianand 1 Malaysian students.
Efforts for capacity building have been continuously conducted. Kyoto University obtained the 21st century
Center of Excellence (COE) program KAGI21 1 in FY2003-FY2007, and hold KAGI21 International Summer
School for four times at ITB in Bandung. Indonesian researchers participated in the school for learning recent
research topics of geosciences. RISH has been awarded other funds for the capacity building. Examples are
Asia-Africa Science Platform Program by Japan Society for Promoting Science (JSPS) “Elucidation ofground-based atmosphere observation network in equatorial Asia” (FY2008-FY2010), JSPS Exchange
Program for East Asian Young Researchers “Fostering Program of Leading Young Scientists toward theEstablishment of Humanosphere Science in East Asia” (FY2009-FY2010), and JSPS-LIPI Joint Research
Project “Japan-Indonesia collaborative study of vertical coupling of the equatorial atmosphere with large
atmospheric radars” (FY2014-FY2016). All these funds were used for the capacity building by lectures inIndonesia, cooperative observations/studies, invitation of Indonesian researchers to scientific meetings inJapan, etc. RISH and LAPAN hold International School on Equatorial Atmosphere (ISQUAR) at Bandung inMarch 18-22, 2019. RISH holds Humanosphere Science School (HSS) in Indonesia in the yearly basis, which
also helps to enhance the science of the humanosphere.
9. Summary and Conclusion
Japan and Indonesia scientific collaboration on the study of the equatorial atmosphere started in the middle
1980s. RISH and LAPAN were the primary institutions for the collaboration. In Indonesia, other institutions
like BPPT, BMKG, and ITB joined the research as well. In 2001 the EAR started operation under thiscollaboration, and was successful for long-term continuous observations until today. RISH is now promoting alarge research project “Study of the coupling processes in the solar-terrestrial system”. One dominant processof the solar energy is the solar radiation that is maximum in the equatorial region. We will study responses tothe solar energy input in the magnetosphere, ionosphere, middle atmosphere and troposphere. RISH and
LAPAN are planning to install the Equatorial MU (EMU) radar, aiming to study and capture the energy andmaterial flow occurring in all height ranges of the equatorial atmosphere — a phenomenon known as theequatorial fountain. We will expand international collaboration on ground-based observation network of
IS/MST radars and other instruments. The observed results will be archived in a database, which will be
widely opened to international community by utilizing a metadata exchange system – IUGONET. We also
pursue capacity building of the younger researcher under our collaboration. RISH and LAPAN will continue
this successful scientific collaboration for long, and will benefit from our research contributing the Earth’s
environmental studies.
KAGI21 is an abbreviation of Kyoto University Active Geosphere Investigation for the 21stCentury COE program.
13
1

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