Statistical study of lightning activity:
Periodicity and possible link with
solar activity
東京工業大学 理工学研究科 基礎物理学専攻
寺澤研究室 修士2年 樋口千夏
Contents
• Introduction
・Solar activity
・Lightning activity
• Analysis and result
• discussion
• summary
1
Contents
• Introduction
・Solar activity
・Lightning activity
• Analysis and result
• discussion
• summary
Variation on solar related parameter
400
[ 10^-22W
/m^2Hz]
F10.7
300
F10.7：solar radio flux(10.7cm)
proxy of UV flux
200
100
0
TSI
[W/m^2]
1367
TSI：Total Solar Irradiance
1365
[count]
1363
GCR：Galactic Cosmic Ray
(Using neutron monitor data)
6000
5000
4000
GCR
1980
1990
2000
GCR
2010
year
11-year period
2
min
max
Variation on solar related parameter
15
x 10
4
F10.7
10
5
PSD[/Hz]
150
10
20
30
40
50
60
70
80
90
100
10
20
30
40
50
60
70
80
90
100
TSI
10
5
150
x 10
5
GCR
10
5
0
E
10
20
30
40
50
60
70
80
90
100
period[day]
27~30-day period
3
GCR
Contents
• Introduction
・Solar activity
・Lightning activity
• Analysis and result
• discussion
• summary
Spectral intensity
Schumann resonance(SR)
7.8
14
20
Freq[Hz]
5
(Sato,2003)
28-day periodicity of global lightning activity
＜observation＞
・at Syowa station in Antarctica (69.018S,39.506E)
・using search coil magnetometer
＜SR power spectrum＞
＜data＞
・2000/2~2003/1
・1~100Hz magnetic field data
(Sato,2003)
Power spectrum
・~5,~10-day periodicity
⇒Correlated with
planetary wave activity
in the tropical region
・~28-day periodicity
28-day
[day]
11
⇒Influence of
solar activity?
4～6
6
Cross-spectral analysis
between global lightning activity and solar parameters
(Sato,2003)
parameter
Period at the
power-spectral
peak[day]
Period at the
cross-spectral
peak[day]
Coherence
Phase(θSR-θpar)
[°]
(timelags[day])
F10.7
27.8
26.9
0.56
+20-90(2-7)
Cosmic Ray(CR)
30.7
30.5
0.47
-
Sun Spot
Number(SSN)
27.7
27.0
0.57
+20-90(2-7)
Kp
26.2
25.6
0.53
0(0)
Dst
27.2
25.3
0.53
0(0)
MeV electron
28.6
29.9
0.52
+110(8)
MeV ion
33.1
31.6
0.58
+20-90(2-7)
Tropical cloud
coverage(>8km)
-
24.0
0.65
±180(0)
※Kp/Dst：Geomagnetic disturbance index
7
Possible scenario of solar influence
on lightning activity
＜regional influence＞
Exp.
UV
---temperature/wind modulation
in stratosphere⇒vertical
circulation⇒convective activity in
troposphere
＜global influence＞
Exp.
GCR
---ionization⇒modulation of
conductivity in atmosphere
through global electric circuit
Indirect influence
GCR
---ionization⇒CCN⇒cloud
---ionization⇒electric breakdown
Direct influence
8
What is MJO?
Madden – Julian Oscillation
--intraseasonal(20-60days)
variability in the tropical
atmosphere
--eastward propagation at 4-8m/s
through the Indian and Pacific
ocean
--characterized by
pressure,cloud amount,rainfall
(Madden and Julian,1972)
9
Contents
• Introduction
・Solar activity
・Lightning activity
• Analysis and result
• discussion
• summary
1.Lightning activity in Japan (45 prefectures)
＜data＞
・ extract from the weather record in JMA
・1989/1～2010/12
・in Japan(except Hokkaido and Okinawa)
Time profile of lightning data in Japan
Monthly distribution
14
35
12
30
10
25
[%]
The number of prefectures
where lightning activity occurs
40
20
8
6
15
4
10
2
5
0
1990
1995
2000
year
2005
2010
10
0
1
2
3
4
5
6
7
month
8
9
10
11
12
※method of Histogram analysis
The number of prefecture
activity occur
where lightning
event count
2
⑥
1
④
⑤
①
②
③
0
1
2
3
4
day
day
5
6
7
1
2
3
4
5
6
power
1（④）
1（⑥）
2（①⑤）
1（②）
0
1（③）
power
個数［個］
period[day]
2
1
0
1
2
3
4
周期［日］
Period[day]
11
5
6
Histogram analysis of lightning activity in Japan(45)
(a)The number of prefectures
where lightning activity occurs：
more 1
2500
600
2000
500
(b)more 5
400
1500
(c)more 10
150
100
300
1000
200
500
0
100
20
40
60
80
100
20
40
60
80
100
0
20
(e)more 12
60
40
60
80
100
80
100
(f)more 13
60
80
40
40
40
20
20
20
20
40
60
80
100
0
0
20
40
60
80
(g)more 14
power
40
20
0
0
(d)more 11
100
0
50
― 3σ
― average
period[day]
20
40
60
80
100
12
100
20
40
60
There is a ~29-day
periodicity
in lightning which
occur in more 12 prf.
1.Lightning activity in Japan (32 prefectures)
＜data＞
・extract from the weather record in JMA
・1989/1～2010/12
・In Japan(except Hokkaido and Okinawa)
・except the area along the sea of Japan
Time profile of lightning data in Japan
18
25
16
14
20
12
[%]
The number of prefectures
where lightning activity occur
Monthly distribution
20
30
15
10
8
10
6
4
5
2
0
0
1990
1995
2000
year
2005
2010
13
1
2
3
4
5
6
7
month
8
9
10
11
12
Histogram analysis of lightning activity in Japan(32)
140
1600
1400
2500
70
80
1400
120
1200
60
28-29-day
power
2000
1200
100
1000
50
60
1000
1500
80
800
40
＜data＞
・extract from the weather record in JMA
・1989/1～2010/12
・in Japan
・except the area along the sea of
Japan
― 3σ data1
平均値
― average
3σ
51-day
・March-October
・the number of prefectures where
lightning activity occurs: more 7
9
8
800
40
60
600
30
1000
600
28-29,51-day periodicity
40
400
20
400
20
500
20
200
10
200
000
⇒influence of
solar activity?
MJO?
10
10
10
20
20
20
30
30
30
40
40
40
50
50
50
60
60
60
period[day]
70
70
70
80
80
80
90
90
90
14
100
100
100
※method of corrrelation analysis
34day
parameter
34
34
34
peak
・・・・
lightning
parameter
・・・・=
・・・・
Ｃ=
＋
lightning
15
Ｃ
Correlation between Ｆ10.7/GCR-lightning(J)
5
10
F10.7
F10.7
F10.7
F10.7
1989-2010
5-10 p20-80
(1989-2010,Mar-Oct)
1989-2010 5-10 p20-80
20
0
-10
-20
-5
-30
-20
-10
0
10
20
30
GCR
GCR
0
-20
-10
0
10
20
30
-30
-20
-10
0
10
20
30
-30
-20
-10
0
10
20
30
0
-10
-50
-30
-20
-10
0
10
20
30
Lightning(J)
-20
Lightning(J)
-30
50
10
lightning(34,more9)
GCR
GCR
20
lightning(34,more9)
0
0.2
0
-0.2
-30
-20
-10
0
10
20
30
time lag[day]
16
0.2
0
-0.2
― 3σ
― 2σ
time lag[day]
Correlation between F10.7-lightning
(2000-2004/9,Mar-Oct)
F10.7
20
0
Lightning
In Africa
-20
-30
-20
-10
0
10
20
30
-30
-20
-10
0
10
20
30
0.04
0.02
0
-0.02
Lightning(J)
-0.04
0.5
0
-0.5
between F10.7 and
・lightning in Africa:
positive correlation
(time lag:0day)
・lightning in Japan
positive correlation
(time lag:20day)
negative correlation
(time lag:7day)
― 3σ
― 2σ
-30
-20
-10
0
10
20
18
30
time lag[day]
Possible scenario of solar influence
on lightning activity
＜regional influence＞
＜global influence＞
Exp.
GCR
---ionization⇒modulation of
conductivity in atmosphere
through global electric circuit
Exp.
UV
---temperature/wind modulation
in stratosphere⇒vertical
circulation⇒convective activity in
troposphere
Indirect influence
GCR
---ionization⇒CCN⇒cloud
---ionization⇒electric breakdown
?
Direct influence
19
Contents
• Introduction
・Solar activity
・Lightning activity
• Analysis and result
• discussion
• summary
Similarity between spectrum of
lightning and OLR in WPWP
(Takahashi,2010)
OLR in WPWP
Lightning
in Japan
雷(34,more9)
70
min
― max max
― min
60
PSD
40
PSD
PSD
50
30
20
10
0
0
10
20
30
40
50
60
period[day]
70
80
90
100
20
Possible scenario for F10.7-MJO-lightning
MJO
F10.7
~27-day
~28-day
?
~40-60-day
MJO
~6m/s
~20day
~28-day
pressure
low
low
Africa
low
low
~12000km
21
low
Japan
low
Contents
• Introduction
・Solar activity
・Lightning activity
• Analysis and result
• discussion
• summary
summary
＜periodicity of lightning in Japan＞
・There are ~28,51-day periodicity for 3 sigma significance
in lightning which occur in more 9 prefectures except
along the sea of Japan .
⇒influence of solar activity or MJO ??
＜correlation between solar activity and lightning＞
・There is a good correlation between lightning in Japan
and F10.7/GCR for 3 sigma significance.
The response is indirect influence of F10.7/GCR on
lightning since there are response time lags.
・There is a good correlation with no time lag between
lightning in Africa and F10.7 for ~3 sigma significance.
⇒possible link between F10.7, MJO and lightning
22