 SHINE, GEM and
CEDAR Joint Campaign
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Event Selection
The purpose of this site is to provide a central location
for joint selection and data summaries of campaign events by the SHINE,
GEM, and CEDAR communities.
- GEM candidate events were selected at the GEM mini-workshop
just prior to the Fall 1998 AGU meeting on the basis that: (1) a relatively
simple CME or high-speed stream/interation region was observed, (2) a classic-looking
storm was triggered and (3) reasonable data sets exist for the event.
- SHINE candidate events were compiled by David Webb
using the criteria that: (1) a LASCO halo CME was observed that appeared
to be aimed Earthward, (2) a clear magnetic structure/cloud was detected
by the WIND and/or ACE spacecraft at L1 3-5 days later, (3) a moderate
or greater level (Dst>-50 nT) geomagnetic storm was triggered.
- CEDAR candidate events meet the requirement that ISR
world days occurred during crucial parts of the magnetic storm interval.
This does not mean that significant CEDAR participation is restricted to
World Days but that these days allow the fullest possible CEDAR collaboration.
Storms that occurred during ISR world days are listed in a table
below.
The best candidates
from the combined lists are given below. These candidate events are separated
into:
- S-N Magnetic Clouds
- N-S Magnetic Clouds
- High-Speed Stream/Interaction Regions
The immediate goal of this site is to select one or
more events that address one or both of the science
focus themes by the end of March so that work can begin on the campaign
prior to the Summer 99 GEM, CEDAR and SHINE meetings and the joint workshop
on Friday, June 18, 1999. The overarching science objective is to improve
our understanding of the geoeffectiveness of events which travel from the
Sun to the Earth using observations along this entire path and models of
CME initation, development, propagation and coupling with the geosphere.
Geoff Reeves has established a web
site to collect summary data and comments on specific events. Depending
on the results of this selection process, we can add events to that list
and begin assembling a more complete picture of the best events. If you
would like to post data or comments about data sets, please email Geoff
Reeves (reeves@lanl.gov)
Please send email with your comments about event selection
to any of the contacts listed below.
Please send data for posting or URL's with data displays
to:
SHINE-GEM-CEDAR Campaign
| Science Focus Candidates |
Science Focus 1 |
Geo-effectiveness of Interplanetary Magnetic Clouds versus
High Speed Stream Interaction Regions |
| Science Focus 2 |
Geo-effectiveness of coronal mass ejections (CMEs) and
their associated Interplanetary Shocks and Magnetic Clouds (IMCs) |
| Return to Top |
|
| Event Candidates |
Storms Triggered by S-N Magnetic
Clouds
| (1)24 Sept- 01 Oct 1998 (min Dst =-233 nT) |
| Solar Source |
Solar Wind Transient |
Magnetic Storm |
Summary/Comments |
- Probable CME assoc. with Flare
with onset at 0640UT on 23 Sept. Flare size was M7 in X-rays and
3B in H-alpha.
- X-ray flare duration >4 hours (an LDE). Location: N18 E09
- Probable assoc. disappearing filament.
- Unfortunately there are no SOHO solar data for this period.
|
- WIND
Plot (UCLA-Wind IMF;
UCLA-Wind Plasma
- IP shock on 24 Sept at 23UT
- Small solar energetic particle (SEP) event at WIND: onset 15 UT on
23 Sept
- IMC (interplanetary magnetic cloud) observed from 25 Sept, 05 - 26,
13 UT with a duration of 32 hours.
- IMC can be fit (but poorly) by a flux
rope model . The rope axis is inclined to the ecliptic plane. The IMF
is slightly northward in most of the IMC, then turns sharply S at the end.
|
- Dst(min)=-233 plot
reached on 25 Sept at 10 UT
- ISR world days on 21-25 Sep 98
- LANL
electron data for 1998 (courtesy of Geoff Reeves).
- Travel time between CME onset and magnetic storm peak is fast: only
51 hours.
|
16 UT on 21 Sept to 16 UT on 25 Sept were ISR World
Days. Good magnetospheric data available. Produced the largest storm
(-233nT) and an inclined flux rope /magnetic cloud. The solar source is
well determined, but there is no SOHO data. This is an ISTP
Sun-Earth Connection event. |
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| 15-18 May 1997
(min Dst =-115 nT) |
| Solar Source |
Solar Wind Transient |
Magnetic Storm |
Summary/Comments |
- Halo
CME first obs. by LASCO at 0630 UT on 12 May. CME spanned 360 deg.
- Assoc flare
onset at 0450 UT on 12 May. Flare size is C1 in X-rays and 1N in H-alpha.
- Duration of disk activity was 14 hours, location at N21W08.
- Event consisted of a small flare and disappearing filament in an active
region followed by a long-lived coronal arcade.
- Twin coronal
dimming regions and an EUV
wave were associated with the CME and surface activity. Refer
to: Thompson et al., GRL, 25, 2465, 1998 & Plunkett et al.,
GRL, 25, 2477, 1998.
|
- Shock observed at Wind at 01 UT on 15 May.
- Small solar energetic particle (SEP) event with onset at 10 UT on 12
May.
- Interplanetary magnetic cloud (IMC) fit to a flux
rope model from 15 May at 09UT to 16, 01UT with a S-N field rotation
in the cloud and a >29 hours duration. (UCLA-Wind
IMF; UCLA-Wind
Plasma
|
- Dst (minimum)~-115 plot
at 13 UT on 15 May during IMC.
- Transit time from onset of CME to magnetic storm peak was 79 hours.
- Data suggest wave acceleration of radiation belt electrons on time
scales of tens of minutes at L=3-4 {Baker et al.,GRL, 2975, 1998.}. SAMPEX
plots
- Case where an active magnetosphere suddenly shuts down, convection
is reduced, the hot plasma fades out, plasmasphere builds up. Should extend
study to May 24 to view magnetosphere as it shuts down (Borovsky, private
communication, 1998)
- AMIE ionospheric electric potential patterns have already been constructed
for this event (per Gang Lu, 12/98).
|
Extremely interesting case which shows radiation belt electron acceleration
at low L value and a very rapid early recovery of the ring current. Well
covered by SOHO: well observed surface assoc. indicating CME aimed at Earth.
Good WIND observations of a clean shock and S-N magnetic cloud. Though not
an ISR World Days interval, the AMIE model has already been run for this
case. |
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(3) 19-31 Oct 1998 (min
Dst =-139 nT) |
| Solar Source |
Solar Wind Transient |
Magnetic Storm |
Summary/Comments |
- Halo
CME onset 1004 UT on 15 Oct. spanning 360 deg.
- Disappearing filament early on 15 Oct. No obvious flare.
- Location of filament activity at N25W25.
- Note activity in region NW of disk center in EIT
195 A movie.
|
- Shock observed at WIND on 18 Oct. at 21 UT
- No SEP seen at WIND.
- IMC on 19 Oct. at 04 UT with S to N magnetic field rotation and duration
of 26 hours.
- Data in interval is messy and does not permit a flux rope fit.
- Solar wind plots (UCLA-Wind IMF;
UCLA-Wind Plasma )
|
- Dst plot
- Very long recovery phase.
- Minimum Dst =-139 nT on 19 Oct. at 13 UT, during IMC passage.
- Transit time from CME onset to peak of magnetic storm was long: 99
hours.
|
16 UT on 19 Oct through 16 UT on 21 Oct are ISR World
Days. A dis. filament/halo CME event. SOHO misses the earliest phase. |
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6-9
Jan 1998(minima in Dst at -83 nT ) |
| Solar Source |
Solar Wind Transient |
Magnetic Storm |
Summary/Comments |
- CME onset at 2328 UT on 2 Jan spanning 360 deg with brightest
region to the W
- B6 Xray flare observed by GOES at 2200 UT on 2 Jan
- Duration of activity > 7 hours
- Disappearing filament observed
- Location of active region in the NW
|
- Shock observed on 6 Jan at 1330 UT
- Possible solar energetic particle (SEP) event at 07 UT on 3 Jan
- 2 IMCs with flux rope structure on 7-8 Jan with durations of 31hrs
and 8 hrs
- Transit times from CME onset to peaks in magnetic storm were 105 hrs
and 116 hrs.
|
- min Dst=-83 nT at 9UT on 7 Jan and -44 nT at 19 UT on 8 Jan
|
Detailed studies of multiple solar flux rope eruptions and WIND obs.
of 2 magnetic clouds with flux rope structure |
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| (4)2-16 May 1998(minima in Dst at -100 nT, -216 nT
and -138 nT) |
| Solar Source |
Solar Wind Transient |
Magnetic Storm |
Summary/Comments |
| min Dst=-100 nT storm interval (plot) |
Not an ISR World Day, but a series of 4 large flare/halo events produced
at least 2 IMCs with lots of interesting interplanetary data at WIND and
ACE. The triggered magnetic activity was triple-peaked and included one
of the largest storms in the present solar cycle on 4 May. |
Activity on 29 April and 01 May contributed to the -100 nT magnetic storm:
- 29 April Activity: CME onset at 1658 UT spanning 360 deg in width.
Flare seen by GOES at 1615 UT with intensity M7 in xrays and 3B in H alpha.
Duration of activity >9 hours. Disappearing filament/LPS likely at >1700
UT. Location of active region S16E22
- Activity on 01 May: CME onset at <2340 UT spanning 360 deg in width.
Flare seen by GOES at2236 UT with intensity M1 in xrays and sF in H alpha.
Duration of activity ~1 hour. Location of active region N25E35
|
- solar wind plots (UCLA-Wind
IMF; UCLA-Wind
Plasma)
- Solar activity on 29 April produced an interplanetary shock (IS) at
Wind on 1 May at 21 UT and a solar energetic particle (SEP) event at 00UT
on 30 April
- Solar activity on 01 May produced an IS at Wind on 3(?)May at 17 UT
and an SEP on 1 May at 12UT
- IMC with flux rope structure observed on 2May at 12 UT with 29 hours
duration
- Transit time from onset of CME to peak of magnetic storm was 73 hours
|
|
| min Dst=-216 nT & -138 nT storm intervals (plot) |
(Two CMEs contributed to the IMC responsible for these storm intervals):
- CME onset at 0531 UT spanning 360 deg with brightest region to the
SW. Flare observed by GOES at 0445UT with intensity C5 in xrays and 1N
in H alpha. Active region located at S20W10. Duration of activity was 1.5
hours.
- CME onset at 1406 UT spanning 360 deg with brightest region to the
NW. Flare observed by GOES at 1331 UT with intensity X1 in xrays and 3B
in H alpha. Active region located at S15W15. Duration of activity was 4.5
hours. Wave structure observed during CME event.
|
- solar wind plots (UCLA-Wind
IMF; UCLA-Wind
Plasma)
- IMC observed on 4 May
- Shock observed at 02 UT on 4 May
- SEP at 16 UT on 2 May associated with 1406 UT CME
- Large He+ event (indicates cold solar material).
- Following IMC on 4May is a recurrent high speed stream with velocity
spikes.
- Transit time from onset of CME to peak of magnetic storm was 49 hours
for -216 nT and 63 hours for -138 nT storm intervals
|
- IMC produced a -216 nT minimum Dst at 06 UT on 4 May and a -138
nT minimum Dst at 05 UT on 5 May
- ISTP
event study
- Very asymmetric ring current -- Polar saw no increase in ring current
flux in a noon- midnight cut near minimum Dst (Joe Fennel, private comm.,
1998
- LANL
electron data for 1998 (courtesy of Geoff Reeves)
|
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Storms Triggered by N-S Magnetic
Clouds
25-27 June 1998
(min Dst=-111 nT)
|
| Solar Source |
Solar Wind Transient |
Magnetic Storm |
Summary/Comments |
- Halo
CME first obs. by LASCO at 18:20 UT on 20 June, spanning 360
deg in width with brightest portion to the SE. Prominence material is seen
in the coronagraph field off the NW limb.
- Possible assoc. Flare:
onset 14:12 UT on 20 June. Size was C4 in X-rays and 1N in H-alpha.
Flare was >1 hr in duration.
- Possible assoc. EPL. Also several disappearing filaments on disk. Possible
location: N13W23.
|
- Probably no shock seen at WIND.
- No SEP seen at WIND.
- Magnetic cloud (IMC) with a flux
rope structure observed from 24 June at 14UT to 25, 16UT. Duration
of 26 hours.
- During this interval the IMF polar direction turns from in the ecliptic
plane to northward, then back to the ecliptic. This fits a rope with its
axis aligned north-south and its leading and trailing fields lying
in the ecliptic plane.
|
- Dst reached its minimum value of -111 nT on 26 Jun at 05 UT (plot)
- LANL
electron data for 1998 (courtesy of Geoff Reeves)
- Transit time from CME onset to magnetic storm peak was ~131 hours.
- The main IMC was mostly northward and was followed by southward
field, possible in a second IMC/flux rope. This later southward field was
likely assoc. with the main storm. The second rope may have been assoc.
with a 150 deg. wide CME first obs. at 05:35UT on 21 June. There is also
a ~C3 flare about this time.
|
A halo and disappearing filaments on June 20, followed by a highly
inclined flux rope which is mostly +Bz on the 24th and 25th, and the storm
when B turns southward on the 26th. |
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Storms Triggered by High
Speed Stream/Interaction Regions
10-20 Mar 1998
(min Dst =-109 nT)
|
| Solar Source |
Solar Wind Transient |
Magnetic Storm |
Summary/Comments |
- Compare with conditions at Sun 2-4 days earlier, or about 7-17 March.
- Solar data was sparse due to bad weather starting about 13 Mar.
- GOES X-ray plots ( 1
, 2
and 3
) show that the Sun was very quiet until 15 Mar. From this time most surface
activity arose from NOAA region 8179 at ~S23 central meridan.
- There were 3 partial halo CMEs on 15-16
, 17
and 18 Mar. It is unclear if the first two were aimed Earthward. The last
CME was assoc. with an EL EPL and not likely geoeffective.
- WSO
source surface magnetic field synoptic map for Carr. rotation 1933.
- Opposite-polarity coronal holes surrounded each pole during this period,
but no obvious, large holes existed equatorward of ~60 deg. latitude. See
Yohkoh X-ray
synoptic map . The region of interest here extends from 0-140 deg.
in longitude.
|
- classic-looking interaction region driven by a recurrent high speed
stream
- ACE & Wind available
- solar wind information Wind-kplot,
UCLA-IMP8,
UCLA-Wind1,
UCLA-Wind2,
Omniweb
- The solar wind polarity (WIND) during the entire period is predominately
toward the Sun, or negative. There are apparent sector boundary crossings
on 10 and 21 Mar.
- Negative pol. agrees with that extrapolated from the WSO source surface
map in the ecliptic from 7-14 Mar. After 14 Mar. the polarity should have
switched to positive (away), the dominant pol. of the Northern hemisphere.
|
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Coincident ISR World Days and Magnetic Storms in 1997-1998
| Magnetic Storm Interval |
ISR World Days |
Comments |
| 10-11 Jan 97 |
6-10 Jan 97 |
|
| 10-12 Apr 97 |
8-10 Apr 97 (some radars stayed on longer) |
|
24 Sept- 01 Oct 1998
|
21-25 Sep 98 |
- SOHO instruments not fully functional yet
- IMC (interplanetary magnetic cloud)
- Dst(min)=-233 plot
- Wind-kplot
|
| 19-27 Oct 98 |
19-21 Oct 98 |
- all but 1 SOHO instrument back on by 15 Oct
- BzS, IMC, multiple ejecta
- Wind-kplot
- Dst(min)=-132 plot
|
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