Transcript Small satellite mission for science and Education

16:20-16:40 Nov.3 2008 Cheng Kung
Oyama et al, J.Geophys.Res.,2008
University,Taiwan
New Perspective of Ionosphere Research
- Lithosphere Atmosphere Ionosphere
coupling –
K.-I..Oyama1, and J.Y.Liu1
( Y.Kakinami 1, T.Kodama2, and H.Kamogawa3 )
1.Institute of Space Science,National Central University, Taiwan
2.Japan Aero Space Exploration Agency,Tukuba,Japan
3. Tokyo Gakuge Univ.,Tokyo,Japan
Great Hanshin-Awaji Earthquake M.7.3 Jan 17,1995 Death 6437 Unknown 3,Injured 43792,
10 chouen (80 chouenn)
This paper stresses that new academic field is being
opened regarding the effects of EQ on ionosphere
CONTENT
1. Past history of the study on the effects of
earthquake by means of satellite data
2. Results from Japanese Hinotori satellite
3. Role of electric field and its possible
generation
mechanism……………………………………
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3. Satellite proposal
Mini satellites and Small satellite,international collaboration
4. Need of international collaboration
The space projects where the ionospheric observation and the
earthquake precursors were studied
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Alouette - 1964
Cosmos-274 -1969
OGO-6 - 1969
OVI-17 - 1969
ISIS-2 – 1971
АЕ-С -1973
GEOS-1 and 2 - 1978
Intercosmos-19 – 1979
Aureol-3 –1981
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Intercosmos-Bulgaria 1300 – 1982
Salyut-7 - 1985
Meteor-3 - 1986
Cosmos 1809 -1987
ISIS-2 – 1971
Activny -(Intercosmos-24) -1989
TOPEX/Poseidon - 1996
GEOS-1 and 2 - 1978
MIR Space Station
DE-2
Quakesat
DEMETER
HINOTORI
Abnormal behavior of Ne, TEC, VLF, ion composition, particle
precipitation, and atmospheric glow have been reported ,which might
have been associated with earthquake.
Cloud ,Temperature rise :recent remote sensing satellites
Ionosphere
Neutral atmosphere is partly ionized by solar EUV in the
mid/low latitude regions .
The ionosphere thus formed is modified
by wind and electric field under the
geomagnetic field.
Mixture of electrons, ions
of various species such as
NO+ and O+,and neutral
particles
Temperatures are defined
for these three particles
such as Te,Ti and Tn
1/2m〈v2〉= 3/2kT
Te is most sensitive
Dynamics
Chemical
Reaction
How to find the earthquake effects on
ionosphere (for ex. ….. Te) ?
1 The instrument should be good enough to give
reliable values
2. Should understand as many features as
possible of the ionosphere , such as morning
overshoot, equator anomaly , plasma bubble,
season ,solar flux, longitude , latitude, local time
time variation 3. construct a model for quiet
condition ( longitude,latitude ,local
time,season,solar flux at single height)
4. study the deviation of Te from the model
( P.S.S., Ann.Geophys, J.G.R.)
This is the history how I was convinced the existence of the
effects of earthquake on ionosphere
Study of the effect of the
Earthquake M≥6.5
(USGS)
•(EQ1) 1981/11/22 15:05
N18.75 E120.84 24km
Ms6.7
•(EQ2) 1982/1/11 6:10
N13.75 E124.36 45km
Ms7.4
•(EQ3) 1982/1/24 6:08
N14.09 E124.35 37km
Ms6.6
２．Ｒｅｓｕｌｔｓ ｆｒｏｍ ＨＩＮＯＴＯＲＩ
satellite
Launched from KSC in
1981 February
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Inclination;31 degrees
Height;576-644 km
Electron Density & Temperature
1981/2/1-1982/6/30/
Electron Temperature
Probe(Te) Hirao, K. and
K.-
I.Oyama, J.Geomag
Geoelectr . ,22,239-402,1970.
Impedance Probe (Ne)
Oya,H.,T.Takahashi,and S.Watanabe,,
J.Geomag.Geoelectr.,38,111-124,1986.
Northern winter
Solar flux variation of Te
Su, Y. Z., K.-I. Oyama, G. J. Bailey, T. Takahashi and S. Watanabe, J. Geophys.
Res., 100, 14591, 1995.
.Oyama, K.-I., M. A. Abdu, N. Balan, G. J. Bailey, S. Watanabe, T. Takahashi, E. R. de Paula, I.
S. Batista, H. Oya and F. Isoda, J. Geophys.Res.,102,417, 1997.
(a) Total disappearance
(b) Partial disappearance
Examples of the deviation of Te and Ne from the model for EQ1 in
the afternoon overshoot for EQ1. 2 days before EQ1 (a)(satellite
pass, 4065), and 1 day after (b)(satellite pass 4110). Ne is shown
for each panel at the lower panels. Black and blue dots show the
model and observation respectively
(a)
Total disappearance
Partial disappearance(b)
Examples of the deviation of Te and Ne from the model for EQ1 in the
afternoon overshoot for EQ2. 2 days before EQ2 (a)(satellite pass, 4815),
and 1 day after (b)(satellite pass 4856). Ne is shown for each panel at
the lower panels. Black and blue dots show the model and observation
What can we find in Ionogram ( ground based ionosonde data) ?
How can we explain Te reduction observed with
satellite(Ne behavior) , together with ionogram
features?
Key word: Westward electric field ?
1.Ionogam data at Manila suggests the contribution of
westward Electric Field(EF). Reduction of h’F and night time
reduction of foF2
2.Satellite data shows that longitudinal distribution of
Te reduction is symmetric with epicenter,
which suggests that Electric field is directing one direction in these
three cases.
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Radial electric field ,which have been suggested so far produces plasma which rotates around
epicenter. If we dare to explain as due to EF,there should be narrow +/- separation region
near epicenter. This narrow charge separation region will be realized only in the low
altitude region. In high altitude region ,this will not be seen.
Possible mechanism for Te reduction
Earthquake origin
Dynamo Electric field is
reduced
Westward Electric
Field
1.Depression of EIA and at the
same time h’F reduces
Ne reduces and the
peak moves toward
Plasma
Equator
fountain
Ratcliffe [1972]
magnetic
field line
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Eastward electric field by Natural wind
2.Plasma is
pushed down
and this action
supplies Ne ,and
helps Ne to
sustain late in
the afternoon
Cartoon showing the mechanism of Te reduction and one evidence
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EQ1
2
EQ2
3
EQ3
Speculation !!!
Plausible mechanism for Electric field generation
1.Large scale(more than 1000 km) wave is generated by latent
hear flux at troposphere; Hagen and Forbes J.G.R.,2002 .
Latent heat release ( Pulinets,cloud formation due to hydro
cluster ions, quantitative study is needed)
2. Modification of E region dynamo electric field;
England et al.,2006,G.R.L
3. Projection of the electric field to topside ionosphere
along magnetic field line； Immel et al.,G.R.L.,2006
Concluding Remarks
Our study shows that precursor of large earthquake seems
to appear in the ionosphere. Although more work should be
done by using existing resources with maximum efforts to
confirm the effect , effort should be made to propose
satellites which are purely dedicated to conduct the
systematic earthquake study among disaster suffering
countries. Micro/Mini satellites can contribute to study the
effect of the earthquake on the ionosphere.Taiwan can play
important role.
The study on EQ effects might open new field in the
ionospheric research which has a long history of about
80 years since the discovery of ionosphere in 1920 ‘s
(Lithosphere-Atmosphere-Ionosphere coupling).
Thank you !
Reduction of Te in afternoon overshoot is found prior to
and after earthquake in low/mid latitude region.
1. Deviation of Te starts about 5 days prior to the earthquake and
recovers to the original value after about 5 days. Deviation of Te
seems to start earlier and recovery is slower as the magnitude of
the earthquake increases.
2.The deviation ranges from 40-60 degrees to the west and 40-60
degrees to the east in longitude from the epicenter . There is a
tendency that larger earthquake shows larger disturbed area.
3.The range of deviation extends from north to south with steep
reduction in high latitude.
4. Ne does not change or shows small increase at the beginning of Te
reduction, but later Ne reduces.
Satellite data
Te:Afternoon overshoot disappears and/or Te merges to
afternoon overshoot in late afternoon
Ne:no clear change or slight reduction (see next summary)
Ionograms
Manila station: h’F reduces in all local times. Especially
afternoon to night ,the height reduces from 400km to about
300 km.
Increase of NmF2 in the late afternoon(result of C oompression of plasma).
Reduction of NmF2 at night . The minimum around 4 LT also reduces(direct effect of westward
electric field).
Taipei station : When NmF2 increases at Manila,NmF2 at
Taipei reduces.