IPY 20072008 Expression of Intent

1
IPY 2007-2008 Expression of Intent 422
Interhemispheric Study on Conjugacy and
Non-conjugacy of Auroral and Polar Ionospheric
Disturbances using Ground-based Observation
NetworkInterhemispheric Study on Auroral
Phenomena Akira Kadokura1, Natsuo Sato1, Hisao
Yamagishi1,Hiroshi Miyaoka1, Makoto Taguchi1,
Akira S. Yukimatu1, Yusuke Ebihara1, and many
other collaborators 1National Institute of Polar
Research, Japan
2
Concise outline of proposed activity ? To
maintain and intensify the pre-existing conjugate
auroral latitude observations between Syowa
Station in Antarctica and observatories in
Iceland. We have carried out the conjugate
ground-based observations continuously since
1984, using the 3-axis fluxgate magnetometer,
3-component induction magnetometer, riometer, and
VLF receiver. We have also carried out auroral
optical observation in the whole season at Syowa
and mainly during the equinox period at Iceland.
So far, many studies concerning the
interhemispheric comparison of various auroral
latitude phenomena have been done using the
observed data. Such a long-term observation is
very valuable to monitor the long-term variation
of the geospace environment surrounding the earth
and can contribute to the Space Weather study.
During the IPY 2007-2008 period, we would like to
renew the data acquisition system to transfer the
data to Japan in near real time and the data
archiving system to make the data accessible for
the community more quickly and more easily. We
would like to also introduce a well-calibrated
automatic optical observation system in Iceland,
which enables us the auroral observation in the
whole season.
3
Concise outline of proposed activity ? To
develop the network of the unmanned magnetometer
system in the Antarctic. We have already
introduced 6 sets of the unmanned magnetometer
system. Four of them were supplied from British
Antarctic Survey (BAS) and two were developed in
National Institute of Polar Research (NIPR). The
data from our system can be obtained via Iridium
satellite system in near real time. We will
further develop and sophisticate our own system,
and would like to increase the number of the
observation points during the IPY 2007-2008
period, collaborating with pre-existing and
planning manned and unmanned magnetometers by
other countries.
4
Concise outline of proposed activity ? To
maintain other ground-based facilities at Syowa
Station, including the Super Dual Auroral Radar
Network (SuperDARN) Syowa South and Syowa East
HF-radars and the imaging riometer. Both are
operated in the framework of the international
collaboration for global network observation. We
will make the data archiving system of these
observations more easily accessible for the
community.
5
Mapping of Northern/Southern hemispheres with
geomagnetic coordinate
6
Conjugate point of Syowa Station (IGRF model)
Comparison of geomagnetic parameters (Epoch
232000 UT, 26 Sep, 2003)
7
Instruments at conjugate stations
8
Unmanned sites in the southern hemisphere
9
Unmanned magnetometers in JARE
JARE-44 (2003) BAS-LPM ? Skallen -6940'24?,
3924'07?E 2003.1/15 2003.10/14 ? Cape
Omega -6834'39.4?, 4104'54.1?E 2003.1/31
2004 1/28 ? H100 6917'44"S, 4119'15"E
2003.1/2 2003.10/22 ? Dome Fuji 7719'01"S,
3942'12"E 2003.2/6 2003.5/29,
2003.12/11-2004.6/9
Syowa
H100
Mizuho
Yamato Mt.
BelgianNew Station
Dome Fuji
10
Comparison of BAS and NIPR type LPMs
11
Development of NIPR model LPM

• Power consumption 0.16 W (winter-time, 1sec
  sampling)
• Magnetometer ON time 100ms at each sampling
• Resolution 0.2 nT, LPF cutoff 15 Hz
• Data recovery By Iridium, once/day
• Telecommunication Data acquisition Command
  sending

Iridium satellite
Transmit time about 20 min for 1 day data (1
sec sampling)
12
BAS-LPM sites in JARE-44 (2003-2004) (3
sites around Syowa, Dome Fuji)
Omega
SYOWA
80km
-
,
H100
Skallen

13
LPMs in JARE-44 in 2003-2004
Cape Omega
Skallen
H100
Dome Fuji
14
Magnetic variation during 20-24 UT on 28 March,
2003
?
?
?
Syowa
Skallen
Omega
H100
Dome
15
Equivalent current variation associated with WTS
passage
16
Field test of NIPR model in JARE-46 in 2005
17
HF-radar network in the both hemisphere(SuperDARN
)
18
Web page of WDC for Aurora
http//polaris.nipr.ac.jp/aurora/