IPY 2007-2008 Expression of Intent #422

Interhemispheric Study on Conjugacy and Non-conjugacy of Auroral and Polar Ionospheric Disturbances using Grou

nd-based Observation Network

Interhemispheric 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

Concise outline of proposed activity

① 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.

Concise outline of proposed activity

② 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.

Concise outline of proposed activity

③ 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.

Mapping of Northern/Southern hemispheres with geomagnetic coordinate

Conjugate point of Syowa Station (IGRF model)

Station

Glat (deg)

Glon (deg)

Inv.lat

(deg)

Mlon (deg

)

MLT (hr)

at 0.0 UT

L valu

e

D (deg)

I (deg)

B (nT)

Tjornes

66.20 -17.12 66.41 71.26 23.46 6.25 -16.21 76.57 52321

Syowa -69.00 39.58 66.27 71.75 23.49 6.17 -48.68 -63.61 43178

Comparison of geomagnetic parameters (Epoch: 23:20:00 UT, 26 Sep, 2003)

SYOWA IcelandFluxgate magnetometer ○

Induction magnetometer ○

Riometer ○

VLF receiver ○

Imaging Riometer ○

All-sky TV camera ○ (only equinox)

All-sky monochromatic Imager ○ (from 2005)

Meridian Scanning Photometer

Fabry-Perot ImagerSuperDARN radar ○

MF-radar

Ionosonde

Multi-beam VHF Doppler radar

Instruments at conjugate stations

Unmanned sites in the southern hemisphere

Unmanned magnetometers in JARE

80 S30 E 40 E 50 E20 E

0 500 km

2000m

3000m

70 S

75 S

Map area

0 90 E

18090 W

昭和基地 S16

みずほ基地

3800m

H260

H15

MD120

MD240

MD364

MD500

MD620

ドームふじ 観測拠点

やまと山脈

MD

（中継拠点）

調査ルート

雪氷基本観測点

45次内陸調査ルート

Dome Fuji

Syowa

JARE-44 (2003) BAS-LPM

① Skallen [-69°40′24″, 39°24′07″E]

2003.1/15 ~ 2003.10/14

② Cape Omega [-68°34′39.4″, 41°04′54.1″E]

2003.1/31 ~ 2004 1/28

③ H100 [69°17'44"S, 41°19'15"E]

2003.1/2 ~ 2003.10/22

④ Dome Fuji [77°19'01"S, 39°42'12"E]

2003.2/6 ~ 2003.5/29, 2003.12/11-2004.6/9Yamato Mt.

H100

BelgianNew Station

Mizuho

１

２

３

４

JARE-45 (2004) BAS-LPM

① H100 [69°17'44"S, 41°19'15"E]

2004.8/18 ~10/20, 10/20~

② Mizuho [70°42‘7.7"S, 44°17‘4.1"E]

2004.10/18 ~

③ Middle Point [74°00’37.0"S, 42°59’30.4"E]

2004.10/29 ~

④ Dome Fuji [77°19'01.6"S, 39°42’31.7"E] 2004.12/22 -

1

2

3

4

JARE-46 (2005) NIPR-LPM

① S122 [70°01'16"S, 43°07'39"E]

② MD120 [71°49'38"S, 44°16'27"E]

JARE-45 BAS-LPMs are continued.

1

2

Comparison of BAS and NIPR type LPMs

BAS-LPM NIPR-LPMMagnetometer MAG-03MC MAG-03MC

Resolution 16 bit 16 bit

Noise level 1 nT 0.2 nTLow Pass Filter 100 Hz 15 Hz

Power consumption(1 sec sampling)

0.42 W 0.16 W

Data acquisitionFlash memory

card

Iridium satelliteFlash memory

card

Command sending × ○

Development of NIPR model LPMPower 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)

- ,

Omega

H100

SYOWA

Skallen

BAS-LPM sites in JARE-44 (2003-

2004)

（ 3 sites around Syowa,

Dome Fuji ）

SITE Lat (deg) Lon (deg) Alt （m）

Start day

End day Days

H100 -69°17′44″ 41°19′15″E 1,317 2003.01.02

2003.10.22

２９３

Skallen -69°40′24″ 39°24′07″E 16 2003.01.15

2003.10.14

２７２

Cape Omega

-68°34′39″ 41°04′54″E 161 2003.01.31

2004.01.28

３６２

Dome Fuji -77°19′01″ 39°42′12″E 3,810 2003.02.06

2003.05.29

１１２

８０ｋｍ

Cape Omega

Skallen

H100

Dome Fuji

LPMs in JARE-44 in 2003-2004

Magnetic variation during 20-24 UT on 28 March, 2003

Skallen

Syowa

Omega

H100

Dome

① ②③

Equivalent current variation associated with WTS passage

Field test of NIPR model in JARE-46 in 2005

HF-radar network in the both hemisphere（ SuperDARN ）

Web page of WDC for Aurora

http://polaris.nipr.ac.jp/~aurora/