Difference between revisions of "05/31/2013 15:30:00 UTC"
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| − | * M. Temmer | + | * M. Temmer >> question: is a CME needed for this or is this a CIR that caused the intense geomagnetic storm of -125 nT? |
| − | + | Jie Zhang: I believe that the slow/gradual May 27 CME is the cause of the intense geomagnetic storm. The CME in LASCO is not even close to a typical halo CME (JAVA movie in SEEDS: http://spaceweather.gmu.edu/seeds/dailymkmovie_ql.php?cme=20130527 ). The extremely faint arm across the equator at a later time indicates a partial halo nature. But as pointed out by Nariaki, it would have been regarded as a backside event, due to the lack of surface signature. | |
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| − | Jie Zhang: I | ||
Dave Webb: I agree this looks like a great candidate for ISEST study. One reason for the lack of consensus may be that the CME/ICME would have passed mostly north of the ecliptic as evidenced by the COR movies. Note that the ACE data show only brief, but intense southward field after the weak shock. Bernie’s IPS and the HI data should help nail this down. Remember also the slow June 2008 event which was deemed a “stealth” or problem CME even with the STEREO obs. (it hit ST-B, not L1). | Dave Webb: I agree this looks like a great candidate for ISEST study. One reason for the lack of consensus may be that the CME/ICME would have passed mostly north of the ecliptic as evidenced by the COR movies. Note that the ACE data show only brief, but intense southward field after the weak shock. Bernie’s IPS and the HI data should help nail this down. Remember also the slow June 2008 event which was deemed a “stealth” or problem CME even with the STEREO obs. (it hit ST-B, not L1). | ||
Manuela Temmer: There was a big CH on May 29, 2013 from which a solar wind flow at 1AU of 750km/s was estimated (see [http://www.uni-graz.at/~temmerma/download/varsiti/2013May31_CH.png] and [http://www.uni-graz.at/~temmerma/download/varsiti/2013May31_SW.png]). The high-speed stream from the CH might have increased the geo-effectiveness of the CME. | Manuela Temmer: There was a big CH on May 29, 2013 from which a solar wind flow at 1AU of 750km/s was estimated (see [http://www.uni-graz.at/~temmerma/download/varsiti/2013May31_CH.png] and [http://www.uni-graz.at/~temmerma/download/varsiti/2013May31_SW.png]). The high-speed stream from the CH might have increased the geo-effectiveness of the CME. | ||
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| + | Bothmer Volker: I have been reluctant to comment on this earlier, but the in-situ data Show a classic CIR with sector boundary. No Need for cme search. Textbook CIR storm. Forward Shocks from HSS at 1Au are not so frequent but they occur. | ||
=Image Data= | =Image Data= | ||
Revision as of 12:54, 23 June 2014
Comment Section
- This is a varSITI campaign event
- M. Temmer >> question: is a CME needed for this or is this a CIR that caused the intense geomagnetic storm of -125 nT?
Jie Zhang: I believe that the slow/gradual May 27 CME is the cause of the intense geomagnetic storm. The CME in LASCO is not even close to a typical halo CME (JAVA movie in SEEDS: http://spaceweather.gmu.edu/seeds/dailymkmovie_ql.php?cme=20130527 ). The extremely faint arm across the equator at a later time indicates a partial halo nature. But as pointed out by Nariaki, it would have been regarded as a backside event, due to the lack of surface signature.
Dave Webb: I agree this looks like a great candidate for ISEST study. One reason for the lack of consensus may be that the CME/ICME would have passed mostly north of the ecliptic as evidenced by the COR movies. Note that the ACE data show only brief, but intense southward field after the weak shock. Bernie’s IPS and the HI data should help nail this down. Remember also the slow June 2008 event which was deemed a “stealth” or problem CME even with the STEREO obs. (it hit ST-B, not L1).
Manuela Temmer: There was a big CH on May 29, 2013 from which a solar wind flow at 1AU of 750km/s was estimated (see [1] and [2]). The high-speed stream from the CH might have increased the geo-effectiveness of the CME.
Bothmer Volker: I have been reluctant to comment on this earlier, but the in-situ data Show a classic CIR with sector boundary. No Need for cme search. Textbook CIR storm. Forward Shocks from HSS at 1Au are not so frequent but they occur.
Image Data
In-Situ Data
A combination of SWEPAM and MAG data from the ACE Satellite:
The blue lines are an approximation of the CME cloud and the red line denotes the shock.
![[1]](http://www.uni-graz.at/~temmerma/download/varsiti/2013May31_CH.png){kind=link}
![[2]](http://www.uni-graz.at/~temmerma/download/varsiti/2013May31_SW.png){kind=link}