1.
CORONAL MASS EJECTIONS (CMEs)
2.
CME SPACE WEATHER EFFECTS
3.
MOTIVATION
4.
METHOD
5.
RESULTS

CORONAGRAPHIC OBSERVATION (direct observations): bright, white-light feature in the coronagraph field of view visible-light observations show the electron-scattered emission of photospheric light the intensity depends on the line-of-sight column density of the corona
Bright feature - mass moving trough corona e.g. Hudson et al. (2006)

SOLAR FLARES
(TYPE II) SOLAR RADIO BURSTS CORONAL (EIT) WAVES
(ERUPTIVE) PROMINENCES
At apparently every observable wavelength!
Low-coronal signatures

Warmuth (2007)
Loss of equilibrium coronal arcade containing prominence material slowly rises
Stretching & twisting of overlying mag. field lines
Magnetic reconnection below the rising arcade: additional mag. flux
Enhanced acceleration
+ thermal/nonthermal energy release (flare)
+
Arcade eruption (CME & eruptive prominence) coronal wave & shock

Animation: www.nasa.gov
Differential rotation + convective flows
Twisting & stretching of mag. field lines
Induced currents (feeding the free energy into the system)
+
Complex magnetic structure
Irreversible loss of equilibrium

1.
CORONAL MASS EJECTIONS (CMEs)
2.
CME SPACE WEATHER EFFECTS
3.
MOTIVATION
4.
METHOD
5.
RESULTS

SLOW
FAST e.g. Vršnak et al (2013)

SOLAR WIND
Constant radial flow of plasma from the solar corona
In situ measurements ACE
Equatorial slice
INTERPLANETARY
MAGNETIC FIELD
Solar mag. field stretches into the interplanetary space
Dipole axis slice

Zurbuchen & Richardson (2006)
Dumbović et al. (2012)

disturbances of the geomagnetic field seen in different indices of geomagnetic activity contribution from auroral currents and ring current
Currents induced by charged particles injected due to magnetic reconnection between ICME & geomagnetic field
ICME Bs and v crucial! (E=Bv)
Dungey (1961), Koskinen&Huttunen (2006), Verbanac et al (2013)
Bmag (nT)
4.00E+01
2.00E+01
0.00E+00
267.5
268.5
Vp (km/s)
9.00E+02
6.00E+02
3.00E+02
0.00E+00
267.5
2.00E+01
1.00E+01
0.00E+00
267.5
-1.00E+01
-2.00E+01
268.5
Bz (nT)
268.5
Dst
100
0
267.5
-100
-200
-300
268.5
In situ/ACE + Dst indeks/Kyoto
DAY
269.5
DAY
269.5
DAY
DAY
269.5
269.5
http://spidr.ngdc.noaa.gov
Animation: www.forskning.no (University of Oslo)

Dumbović et al (2012)
Short term decreases in galactic cosmic ray
(GCR) flux:
Typical duration-several days
Magnitude up to ~ 30 %
Due to interaction of GCRs with shock/sheath region and
CME/ejecta region (different mechanisms)
Increased B and v crucial!
Dumbović et al (2011), Richardson & Cane (2011),
Dumbović et al (2012), Belov et al (2014)
MAGNETIC CLOUDS:
Type of CME/ejecta
Typical “pot-shaped” symmetric FDs
Richardson & Cane (2011)
Heber et al (2015)

All extreme storms – Forbush decreases (Vennerstrom et al., 2015 & Lefevre et al., 2015 in preparation)
Forbush decreases not necessarily associated with intense storms (e.g. Maričić et al., 2014)

1.
CORONAL MASS EJECTIONS (CMEs)
2.
CME SPACE WEATHER EFFECTS
3.
MOTIVATION
4.
METHOD
5.
RESULTS

CME detection:
Initial conditions
Modeling of CME propagation & evolution
Prediction of ICME arrival and near-Earth properties
Modeling of geomagnetic storms and Forbush decreases
~ 1 day ~ 1 h

CME detection:
Initial conditions
Statistical relations
Empirical probabilistic model
Modeling of geomagnetic storms and Forbush decreases
~ 1 day

1.
CORONAL MASS EJECTIONS (CMEs)
2.
CME SPACE WEATHER EFFECTS
3.
MOTIVATION
4.
METHOD
5.
RESULTS

Make a sample of events
Select CMEs and their properties
Associate geomagnetic storms
Associate Forbush decreases
Statistical analysis
Select key CME properties
Find CME-GMS relations
Find CME-FD relations
Model
Employ the results of the statistical analysis

CME-SOLAR FLARE ASSOCIATION (more parameters!):
M9 flare
N19W36 CME v
0
=1315.1km/s
CME-GEOMAGNETIC STORM ASSOCIATION (or no storm!):
HALO
Easy to find
Forbush decrease
(if present!)
Dumbović et al (2015)

guided by previous studies:
Zhang et al. (2003), Srivastava & Venkatakrishnan (2004), Srivastava (2005), Gopalswamy et al. (2007),
Zhang et al. (2007), Richardson & Cane (2011), Kim et al. (2012)
M9 flare
N19W36 CME v
0
=1315.1km/s
Associated flare X-ray flux peak and source position
CME speed
HALO
CME apparent width
CME-CME interaction parameter (likeliness of CME-CME interaction)
Kinematical criterion
+
Timing criterion
+
Source position/width criterion
Dumbović et al (2015)
4 levels of interaction:
No interaction
Not likely
Likely
Very likely

500
400
300
200
100
0
0 y = 0,04x + 10,84
R² = 0,10
500 1000 1500 2000 2500 3000 3500 4000

500
400
300
200
100
0
0 y = 0,04x + 10,84
R² = 0,10
500 1000 1500 2000 2500 3000 3500 4000

V=400-600 km/s V=800-1000 km/s V=1200-1700 km/s
Dumbović et al (2015)

Dumbović et al (in preparation)

1.
CORONAL MASS EJECTIONS (CMEs)
2.
CME SPACE WEATHER EFFECTS
3.
MOTIVATION
4.
METHOD
5.
RESULTS

The change of the Dst distribution mean with
CME/flare parameters:
CME speed, v
CME apparent width, w
CME-CME interaction parameter, i
CME/flare source position, r
Flare X-ray class, f
STRONGER STORMS
ARE CAUSED BY: faster CMEs wider CMEs interacting CMEs central CME/flares stronger flares
Dumbović et al (2015)

http:// oh.geof.unizg.hr/ CGEFT/cgeft.php

The change of the FD distribution mean with
CME/flare parameters:
CME speed, v
CME apparent width, w
CME-CME interaction parameter, i
CME/flare source position, r
Flare X-ray peak intensity, I
DEEPER FDs ARE
CAUSED BY: faster CMEs wider CMEs interacting CMEs central CME/flares stronger flares
Dumbović et al (in preparation)

http:// oh.geof.unizg.hr
/FDFT/fdft.php

EVALUATION MEASURE – HEIDKE SKILL SCORE (meteorology!):
∞<HSS<1
HSS=0 as good as a random guess
HSS<0 worse than a random guess
HSS>0 better than a random guess
HSS=1 perfect forecast
REFERENCE – human forecast (SIDC*) whether or not there will be storm, HSS=0.34
Devos et al (2014)
Solar Influences Data Center (at ROB, BEL) storm no effect 0.19
medium 0.22
strong 0.08
intense 0.28
FD
0.24
0.08
0.16
0.31
no intense effect no strong or intense effect storm
0.28
0.10
there will be an effect (SIDC) 0.19
Devos et al (in preparation),
Dumbović et al (in preparation)
FD
0.31
0.50
0.24

 The presented research is based on:
Dumbović et al. (2015), Sol.Phys.
Dumbović et al (2015) in preparation
Devos et al (2015) in preparation
 The presented research is partly based on:
Dumbović et al (2011), A&A
Dumbović et al (2012), A&A
Dumbović et al (2012), CEAB
Maričić et al (2014), Sol.Phys.
Heber et al (2015) submitted to CEAB
Lefevre et al (2015) in preparation
Vennerstrom et al (2015) in preparation
The work leading to this research was (partly) funded by:
EU FP7 project COMESEP (Coronal Mass Ejections and Solar Energetic Particles)
HRZZ project SOLSTEL (Solar and Stelar variability)
EU FP7 project SOTERIA (SOlar-TERrestrial Investigations and Archives)
HEP (national) project “Predviđanje učinaka Sunčevih koroninih izbačaja na Zemljino magnetsko polje”
Research grant at the Royal Observatory of Belgium “Testing and improvement of the CME Geomagnetic Forecast Tool (CGFT)”
Bilateral MZOŠ/DAAD project CORAMOD ( Cosmic ray modulation by solar coronal mass ejections)