From David.Webb@hanscom.af.mil Fri Mar 4 10:23:21 2005 Return-Path: Received: from fsmxrd02.hanscom.af.mil (thunderbird.hanscom.af.mil [129.53.219.254]) by sv01.scs.gmu.edu (8.13.1/8.12.8) with ESMTP id j24FNLYd008254 for ; Fri, 4 Mar 2005 10:23:21 -0500 Received: by fsmxrd02.hanscom.af.mil with Internet Mail Service (5.5.2657.72) id ; Fri, 4 Mar 2005 10:23:16 -0500 Message-ID: <010F73C38C145744BAE4599B97F020E302D5B2C6@ml66sc-mb-05.hanscom.af.mil> From: Webb David F Contr AFRL/VSBX To: "'Andrei Zhukov'" , Nariaki Nitta , Ian Richardson Cc: Alejandro Lara , Alexander Nindos , Angelos Vourlidas , Barbara Thompson , Chin-Chun Wu , Christophe Marque , Daniel Berdichevsky , Doug Biesecker , Cliver Edward W Civ AFRL/VSBXS , Emilia Huttunen , Georgoulis Manolis , Hong Xie , Jie Zhang , John Steinberg , Justin Kasper , Nat Gopalswamy , Robert MacDowall , Ryuho Kataoka , Seiji Yashiro , Vasyl Yurchyshyn , Volker Bothmer , Yang Liu Subject: RE: superstorms? Date: Fri, 4 Mar 2005 10:23:13 -0500 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2657.72) Status: O X-UID: 25185 Content-Length: 7038 X-Keywords: Content-Type: text/plain; charset=iso-8859-1 X-Evolution-Source: imap://jiez@mail.scs.gmu.edu/ X-Evolution: 00000002-0051 Jie, and all, This discussion of event 22, Oct 1999, raises a problem with me. We need to somehow archive these emails relating to specific events on the website so we can retrieve them at the workshop. Perhaps you can save all the general WG1 emails in a single dir. If so, I suggest archiving all of them from several weeks ago to the present, and up to the start of the workshop. Also, this will be useful after the workshop for followup work on these events. What does everyone else think about this? Regards, Dave -----Original Message----- From: Andrei Zhukov [mailto:Andrei.Zhukov@oma.be] Sent: Friday, March 04, 2005 8:42 AM To: Nariaki Nitta; Ian Richardson Cc: Webb David F Contr AFRL/VSBX; 'jukozyra@engin.umich.edu'; Alejandro Lara; Alexander Nindos; Angelos Vourlidas; Barbara Thompson; Chin-Chun Wu; Christophe Marque; Daniel Berdichevsky; Doug Biesecker; Cliver Edward W Civ AFRL/VSBXS; Emilia Huttunen; Georgoulis Manolis; Hong Xie; Jie Zhang; John Steinberg; Justin Kasper; Nat Gopalswamy; Robert MacDowall; Ryuho Kataoka; Seiji Yashiro; Vasyl Yurchyshyn; Volker Bothmer; Yang Liu Subject: Re: superstorms? I have also checked the event 22 (October 22, 1999). Interplanetary signature: I agree with Ian that it's an ICME interacting with the fast flow from a coronal hole. Note that this ICME has signatures of an over-expanding ICME: enhanced density and magnetic field at the front and at the end, with a possible fast reverse shock right after 6:00 on Oct. 22. But this may be due to the compression of the ICME's rear part by the following fast stream. I'm not sure if it is a magnetic cloud, but if so, it should be of the NWS type. Following coronal hole has N polarity. Solar source: I fully agree with Nariaki. A partial halo CME (not reported in any catalogue) is first barely seen above the LASCO C2 occulter at 23:50 on Oct. 17, above the SSE limb. At the same time another CME (narrow, 87 deg width, PA 40 according to Gopal's catalogue) appears above the NE limb. However, these are TWO different CMEs as can be seen in running difference images around 6:50 Oct. 18. A relatively narrow bright CME is above the NE limb, and a weak partial halo spans the solar limb from ENE to SSW. Above the ENE limb it overlaps with quasi-radial structures of the narrow CME. At 23:11 EIT shows two simultaneous eruptions: at S28E11 and N05E37 (coordinates only to guide the eye, both regions are quite extended). Both have very clear dimmings (see running difference movie at ftp://omaftp.oma.be/pub/astro/andreiz/CDAW/EIT195_19991017-18.gif), the southern one has also a post-eruption arcade and the heated erupting filament matter. This unambiguously demonstrates the occurrence of a CME. The simultaneity of two eruptions (as far as we can determine with the limited EIT temporal cadence) makes me think that they represent signatures of one large-scale eruption which is visible as a partial halo CME by C2. SXT and EIT 284 data suggest that these two regions are magnetically connected. I don't think that these two eruption centers correspond to two CMEs seen by LASCO. LASCO shows the erupted matter predominantly above the NE limb and the partial halo is very weak. On the contrary, EIT data suggests that the most of the plasma was erupted from the southern source region. It seems that the narrow CME above the NE limb is a backside one - EIT shows no more eruptive signatures around this time. This event demonstrates that sometimes EIT can show more obvious CME signatures than LASCO. A space weather forecaster could miss such a weak partial halo CME, and such a severe storm may be unpredicted! Additionally, it suggests that it may be not correct to talk about a single localized CME source region. Andrei. On Friday 04 March 2005 06:31, Nariaki Nitta wrote: > Hello Ian, > > Thank you for the message, which clarified lots of things, together with > the informative plots of ACE data (with Dst). > > Indeed I see in SXT data > (http://www.lmsal.com/nitta/movies/sxt_almg_19991017_09/SXT_AlMg_19991017_0 >9.html) a global coronal restructuring between 17-Oct-1999 22 UT and > 18-Oct-1999 03 UT (between a long data gap). The EIT daily MPEG movie at > NRL > (http://lasco-www.nrl.navy.mil/daily_mpg/1999_10/991017_195.mpg) also > shows corresponding large-scale changes and an eruption from a southern > region at 23:11 (see also > http://www.lmsal.com/nitta/movies/eit_19971017_18/EIT195_19991017_18.html). > Note that these locations are far from the active region (AR 8731) > responsible for the 20-Oct-1999 filament eruption and the perhaps > associated slow CME. It is just west of the coronal hole that provided > the high speed stream as you wrote. Note that Jie's latest list > (http://cdaw.gsfc.nasa.gov/geomag_cdaw/data/cdaw1/Zhang_source/Data_Sun_Sou >rce_Zhang.html) mentions a CME at "1998/10/18 01:26 PA: 135; C2; C3 (not in > catalog)." I presume it is 1999/10/18. It would be beneficial if someone > produces a LASCO movie around this time. > > This particular event indicates the need for collaborations of experts > of various distances from the solar surface just to identify the origin > of some of the storms. > > Good night, > > Nariaki > > Ian Richardson wrote on 03.03.2005 20:35: > > Hi Nariaki, > > > > Oh yes, that event! My take is that this is a high-speed stream that is > > interacting with an ICME. The interface betweeh the two structures may > > be at ~6 UT on Oct 22, although ICME-like plasma composition (e.g., > > enhanced O7/O6, Fe charge states) does appear to persist to ~12 UT. The > > exceptionally strong storm presumably arises from the strong southward > > field in the structured) ICME, possibly enhanced by compression of the > > ICME magnetic field by the interaction with the high-speed stream. > > > > Anyone else have an opinion? > > > > The slow CME can probably be ruled out as the source of the ICME refered > > to above. The ICME has arrived at Earth by ~8 UT on October 21. This > > is only 26 hours after the CME, implying a high transit speed of ~1625 > > km/s. This seems incompatible with the slow (327 km/s) CME at the Sun > > and the modest (<~500 km/s) in-situ speed of the ICME. (Furthermore, the > > associated ICME-driven shock arrived even (~6 hours) earlier!) In > > addition, my impression is that the EIT activity associated with this > > CME was towards the west limb, (so the "E15" location is surprising) and > > that the CME rises above the west limb. I suspect that this CME was > > probably not directed towards the Earth. > > > > I would imagine that the true source of the ICME would be reasonably > > close to central meridian ~3-4 days prior to October 21, i.e. around > > October 17-18, perhaps in the same AR as that producing the October 20 > > CME. > > > > EIT 284 A observations do show a small near-equatorial coronal hole at ~ > > central meridian on October 21 that presumably could be the source of > > the high-speed stream. > > > > Regards, > > > > Ian From nitta@lmsal.com Thu Mar 3 19:26:41 2005 Return-Path: Received: from lmsal.com (mail.lmsal.com [198.116.7.6]) by sv01.scs.gmu.edu (8.13.1/8.12.8) with ESMTP id j240Qfnp023116 for ; Thu, 3 Mar 2005 19:26:41 -0500 Received: from [198.116.7.1] (account nitta HELO [198.62.143.100]) by lmsal.com (CommuniGate Pro SMTP 4.2.9) with ESMTP-TLS id 3021731; Thu, 03 Mar 2005 16:26:34 -0800 Message-ID: <4227AB39.4020702@lmsal.com> Date: Thu, 03 Mar 2005 16:26:33 -0800 From: Nariaki Nitta User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.2) Gecko/20040804 Netscape/7.2 (ax) X-Accept-Language: en, pdf, ja MIME-Version: 1.0 To: Ian Richardson CC: Webb David F Contr AFRL/VSBX , "'jukozyra@engin.umich.edu'" , Alejandro Lara , Alexander Nindos , Andrei Zhukov , Angelos Vourlidas , Barbara Thompson , Chin-Chun Wu , Christophe Marque , Daniel Berdichevsky , Doug Biesecker , Ed Cliver , Emilia Huttunen , Georgoulis Manolis , Hong Xie , Jie Zhang , John Steinberg , Justin Kasper , Nat Gopalswamy , Robert MacDowall , Ryuho Kataoka , Seiji Yashiro , Vasyl Yurchyshyn , Volker Bothmer , Yang Liu Subject: Re: superstorms? References: <010F73C38C145744BAE4599B97F020E302D5B2BC@ml66sc-mb-05.hanscom.af.mil> <6.1.2.0.0.20050303175210.01b46008@lheapop.gsfc.nasa.gov> In-Reply-To: <6.1.2.0.0.20050303175210.01b46008@lheapop.gsfc.nasa.gov> Content-Transfer-Encoding: 7bit Status: RO X-UID: 25150 Content-Length: 3224 X-Keywords: Content-Type: text/plain; charset=us-ascii; format=flowed X-Evolution-Source: imap://jiez@mail.scs.gmu.edu/ X-Evolution: 00000004-0010 And No. 22 is a difficult case, isn't it? Jie's list shows a CIR (can it be the source of a superstorm?), and Nat's list shows a slow CME (20-Oct-1999 06 UT) perhaps associated with a minor filament eruption. TRACE data (e.g., http://www.lmsal.com/nitta/movies/19991020_05/trace195/TRACE195_991020_05.html) indicate a reluctant filament eruption.... Regards Nariaki Ian Richardson wrote on 03.03.2005 15:00: > No events before no. 22 - presumably consistent with the the previously > reported tendency for particularly energetic events (SEPs, GLEs, Forbush > decreases, fast CMEs/ICMEs, etc) generally to occur more frequently > following, rather than before, solar maximum. > > > At 04:17 PM 3/3/2005, Webb David F Contr AFRL/VSBX wrote: > >> Jie, >> I suggest you label these particular storms in our list. They are >> numbers 22, 25, 27, 37, 38, 47, 68, 69, 70, 7-10 Nov. 2004 (yet to be >> added and a big reason to add it!). Apparently there are none before >> No. 22 in our list that qualify. >> >> Regards, >> Dave >> >> -----Original Message----- >> From: jukozyra@engin.umich.edu [mailto:jukozyra@engin.umich.edu] >> Sent: Thursday, March 03, 2005 4:03 PM >> To: Webb David F Contr AFRL/VSBX >> Subject: Re: superstorms? >> >> >> Hi Dave, >> >> I won't be at the CDAW, Mike Liemohn is representing our group there. >> >> The question of "what is a superstorm?" is a good one. We are looking >> at this >> more carefully now for a presentation in Toulouse this summer. >> However, in the >> past I have been using Dst<-240 nT from Mac-Mahon et al., JGR 102, >> 14199, 1997. >> Another paper, which Susan Gussenhoven participated in, uses 4 different >> magnetic indices (ap, Kp, AE and Dst) to pick out the top 2% of severe >> magnetic storms [Bell et al.,JGR, 14189, 1997]. >> >> My list of superstorms since 1999 based on Dst* (ring current strength) >> includes: >> >> 22-23 Oct 1999 >> 6-7 April 2000 >> 15-16 July 2000 >> 31 March - 1 April 2001 (double-peaked) >> 11-12 April 2001 >> 6-7 Nov 2001 >> 29-31 Oct 2003 (double-peaked) >> 20-21 Nov 2003 >> 7-10 Nov 2004 (double-peaked) >> >> If I can be of any other help, let me know. >> >> Regards, >> Janet >> >> >> >> >> This is actually from a paper by >> >> Quoting Webb David F Contr AFRL/VSBX : >> >> > Janet, >> > I don't know if you are going to the Storm CDAW in 2 weeks, but we are >> > studying the 77 storms with Dst < -100 nT. We have discussed >> analyzing the >> > solar inputs for superstorms and this is a good opportunity. Can you >> provide >> > me with a dsfinition of a superstorm, eg, is it just the Dst level or >> > sonething more, and a sublist of superstorms from the CDAW list ?: >> > http://cdaw.gsfc.nasa.gov/geomag_cdaw/Data.html >> > >> > Thanks, >> > Regards, >> > Dave >> > >> > >> > David F. Webb >> > AFRL/VSBXS & ISR; Boston College >> > 29 Randolph Road >> > Hanscom AFB, MA 01731-3010 >> > Tel.: 781-377-3086 Fax: 781-377-3160 >> > E-mail: david.webb@hanscom.af.mil >> > URL(updated 2003): http://www2.bc.edu/~webbd >> > > > > -- > Ian Richardson > Code 661, GSFC, Greenbelt, MD 20771 (Building 2, Rm 25) > Tel: 301-286-3079; Fax: 301-286-1682; From David.Webb@hanscom.af.mil Fri Mar 4 11:06:09 2005 Return-Path: Received: from FSMXRD01.hanscom.af.mil (thunderbird.hanscom.af.mil [129.53.219.254]) by sv01.scs.gmu.edu (8.13.1/8.12.8) with ESMTP id j24G69g4008639 for ; Fri, 4 Mar 2005 11:06:09 -0500 Received: by fsmxrd01.hanscom.af.mil with Internet Mail Service (5.5.2657.72) id ; Fri, 4 Mar 2005 11:06:04 -0500 Message-ID: <010F73C38C145744BAE4599B97F020E302D5B2C9@ml66sc-mb-05.hanscom.af.mil> From: Webb David F Contr AFRL/VSBX To: "'jiez@scs.gmu.edu'" Subject: RE: superstorms? Date: Fri, 4 Mar 2005 11:06:03 -0500 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2657.72) Status: O X-UID: 25195 Content-Length: 8358 X-Keywords: Content-Type: text/plain; charset=iso-8859-1 X-Evolution-Source: imap://jiez@mail.scs.gmu.edu/ X-Evolution: 00000006-0111 Jie, It is worth doing after the workshop but its real usefulness will be if the emails are available to us AT the workshop. Otherwise people have to bring paper copies or reconstruct what they said. Perhaps I can find out how to copy those I have and bring them with me. Dave -----Original Message----- From: Jie Zhang [mailto:jiez@scs.gmu.edu] Sent: Friday, March 04, 2005 10:57 AM To: Webb David F Contr AFRL/VSBX Cc: 'Andrei Zhukov'; Nariaki Nitta; Ian Richardson; Alejandro Lara; Alexander Nindos; Angelos Vourlidas; Barbara Thompson; Chin-Chun Wu; Christophe Marque; Daniel Berdichevsky; Doug Biesecker; Cliver Edward W Civ AFRL/VSBXS; Emilia Huttunen; Georgoulis Manolis; Hong Xie; John Steinberg; Justin Kasper; Nat Gopalswamy; Robert MacDowall; Ryuho Kataoka; Seiji Yashiro; Vasyl Yurchyshyn; Volker Bothmer; Yang Liu Subject: RE: superstorms? Dave, this is a good idea. This can be done for a few controversial events. But I may have to do it after the workshop. -Jie On Fri, 2005-03-04 at 10:23, Webb David F Contr AFRL/VSBX wrote: > Jie, and all, > This discussion of event 22, Oct 1999, raises a problem with me. We need to somehow archive these emails relating to specific events on the website so we can retrieve them at the workshop. Perhaps you can save all the general WG1 emails in a single dir. If so, I suggest archiving all of them from several weeks ago to the present, and up to the start of the workshop. Also, this will be useful after the workshop for followup work on these events. > > What does everyone else think about this? > > Regards, > Dave > > -----Original Message----- > From: Andrei Zhukov [mailto:Andrei.Zhukov@oma.be] > Sent: Friday, March 04, 2005 8:42 AM > To: Nariaki Nitta; Ian Richardson > Cc: Webb David F Contr AFRL/VSBX; 'jukozyra@engin.umich.edu'; Alejandro > Lara; Alexander Nindos; Angelos Vourlidas; Barbara Thompson; Chin-Chun > Wu; Christophe Marque; Daniel Berdichevsky; Doug Biesecker; Cliver > Edward W Civ AFRL/VSBXS; Emilia Huttunen; Georgoulis Manolis; Hong Xie; > Jie Zhang; John Steinberg; Justin Kasper; Nat Gopalswamy; Robert > MacDowall; Ryuho Kataoka; Seiji Yashiro; Vasyl Yurchyshyn; Volker > Bothmer; Yang Liu > Subject: Re: superstorms? > > > I have also checked the event 22 (October 22, 1999). > > Interplanetary signature: I agree with Ian that it's an ICME interacting with > the fast flow from a coronal hole. Note that this ICME has signatures of an > over-expanding ICME: enhanced density and magnetic field at the front and at > the end, with a possible fast reverse shock right after 6:00 on Oct. 22. But > this may be due to the compression of the ICME's rear part by the following > fast stream. I'm not sure if it is a magnetic cloud, but if so, it should be > of the NWS type. Following coronal hole has N polarity. > > Solar source: I fully agree with Nariaki. A partial halo CME (not reported in > any catalogue) is first barely seen above the LASCO C2 occulter at 23:50 on > Oct. 17, above the SSE limb. At the same time another CME (narrow, 87 deg > width, PA 40 according to Gopal's catalogue) appears above the NE limb. > However, these are TWO different CMEs as can be seen in running difference > images around 6:50 Oct. 18. A relatively narrow bright CME is above the NE > limb, and a weak partial halo spans the solar limb from ENE to SSW. Above the > ENE limb it overlaps with quasi-radial structures of the narrow CME. > > At 23:11 EIT shows two simultaneous eruptions: at S28E11 and N05E37 > (coordinates only to guide the eye, both regions are quite extended). Both > have very clear dimmings (see running difference movie at > ftp://omaftp.oma.be/pub/astro/andreiz/CDAW/EIT195_19991017-18.gif), the > southern one has also a post-eruption arcade and the heated erupting filament > matter. This unambiguously demonstrates the occurrence of a CME. The > simultaneity of two eruptions (as far as we can determine with the limited > EIT temporal cadence) makes me think that they represent signatures of one > large-scale eruption which is visible as a partial halo CME by C2. SXT and > EIT 284 data suggest that these two regions are magnetically connected. > > I don't think that these two eruption centers correspond to two CMEs seen by > LASCO. LASCO shows the erupted matter predominantly above the NE limb and the > partial halo is very weak. On the contrary, EIT data suggests that the most > of the plasma was erupted from the southern source region. It seems that the > narrow CME above the NE limb is a backside one - EIT shows no more eruptive > signatures around this time. > > This event demonstrates that sometimes EIT can show more obvious CME > signatures than LASCO. A space weather forecaster could miss such a weak > partial halo CME, and such a severe storm may be unpredicted! Additionally, > it suggests that it may be not correct to talk about a single localized CME > source region. > > Andrei. > > > On Friday 04 March 2005 06:31, Nariaki Nitta wrote: > > Hello Ian, > > > > Thank you for the message, which clarified lots of things, together with > > the informative plots of ACE data (with Dst). > > > > Indeed I see in SXT data > > (http://www.lmsal.com/nitta/movies/sxt_almg_19991017_09/SXT_AlMg_19991017_0 > >9.html) a global coronal restructuring between 17-Oct-1999 22 UT and > > 18-Oct-1999 03 UT (between a long data gap). The EIT daily MPEG movie at > > NRL > > (http://lasco-www.nrl.navy.mil/daily_mpg/1999_10/991017_195.mpg) also > > shows corresponding large-scale changes and an eruption from a southern > > region at 23:11 (see also > > http://www.lmsal.com/nitta/movies/eit_19971017_18/EIT195_19991017_18.html). > > Note that these locations are far from the active region (AR 8731) > > responsible for the 20-Oct-1999 filament eruption and the perhaps > > associated slow CME. It is just west of the coronal hole that provided > > the high speed stream as you wrote. Note that Jie's latest list > > (http://cdaw.gsfc.nasa.gov/geomag_cdaw/data/cdaw1/Zhang_source/Data_Sun_Sou > >rce_Zhang.html) mentions a CME at "1998/10/18 01:26 PA: 135; C2; C3 (not in > > catalog)." I presume it is 1999/10/18. It would be beneficial if someone > > produces a LASCO movie around this time. > > > > This particular event indicates the need for collaborations of experts > > of various distances from the solar surface just to identify the origin > > of some of the storms. > > > > Good night, > > > > Nariaki > > > > Ian Richardson wrote on 03.03.2005 20:35: > > > Hi Nariaki, > > > > > > Oh yes, that event! My take is that this is a high-speed stream that is > > > interacting with an ICME. The interface betweeh the two structures may > > > be at ~6 UT on Oct 22, although ICME-like plasma composition (e.g., > > > enhanced O7/O6, Fe charge states) does appear to persist to ~12 UT. The > > > exceptionally strong storm presumably arises from the strong southward > > > field in the structured) ICME, possibly enhanced by compression of the > > > ICME magnetic field by the interaction with the high-speed stream. > > > > > > Anyone else have an opinion? > > > > > > The slow CME can probably be ruled out as the source of the ICME refered > > > to above. The ICME has arrived at Earth by ~8 UT on October 21. This > > > is only 26 hours after the CME, implying a high transit speed of ~1625 > > > km/s. This seems incompatible with the slow (327 km/s) CME at the Sun > > > and the modest (<~500 km/s) in-situ speed of the ICME. (Furthermore, the > > > associated ICME-driven shock arrived even (~6 hours) earlier!) In > > > addition, my impression is that the EIT activity associated with this > > > CME was towards the west limb, (so the "E15" location is surprising) and > > > that the CME rises above the west limb. I suspect that this CME was > > > probably not directed towards the Earth. > > > > > > I would imagine that the true source of the ICME would be reasonably > > > close to central meridian ~3-4 days prior to October 21, i.e. around > > > October 17-18, perhaps in the same AR as that producing the October 20 > > > CME. > > > > > > EIT 284 A observations do show a small near-equatorial coronal hole at ~ > > > central meridian on October 21 that presumably could be the source of > > > the high-speed stream. > > > > > > Regards, > > > > > > Ian From Andrei.Zhukov@oma.be Fri Mar 4 08:48:58 2005 Return-Path: Received: from bonnie.oma.be (bonnie.oma.be [193.190.231.71]) by sv01.scs.gmu.edu (8.13.1/8.12.8) with ESMTP id j24DmvQC007369 for ; Fri, 4 Mar 2005 08:48:58 -0500 Received: from sol007.oma.be (bonnie.oma.be [193.190.231.71]) by bonnie.oma.be (8.11.1 (Revision 1.5) /8.11.1) with ESMTP id j24Dj8P24793; Fri, 4 Mar 2005 13:45:08 GMT From: Andrei Zhukov Organization: ROB To: Nariaki Nitta , Ian Richardson Subject: Re: superstorms? Date: Fri, 4 Mar 2005 13:42:27 +0000 User-Agent: KMail/1.5.4 Cc: Webb David F Contr AFRL/VSBX , "'jukozyra@engin.umich.edu'" , Alejandro Lara , Alexander Nindos , Angelos Vourlidas , Barbara Thompson , Chin-Chun Wu , Christophe Marque , Daniel Berdichevsky , Doug Biesecker , Ed Cliver , Emilia Huttunen , Georgoulis Manolis , Hong Xie , Jie Zhang , John Steinberg , Justin Kasper , Nat Gopalswamy , Robert MacDowall , Ryuho Kataoka , Seiji Yashiro , Vasyl Yurchyshyn , Volker Bothmer , Yang Liu References: <010F73C38C145744BAE4599B97F020E302D5B2BC@ml66sc-mb-05.hanscom.af.mil> <6.1.2.0.1.20050303223812.01da2d80@lheapop.gsfc.nasa.gov> <422800B0.4020503@lmsal.com> In-Reply-To: <422800B0.4020503@lmsal.com> MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline Message-Id: <200503041342.27436.Andrei.Zhukov@oma.be> Status: O X-UID: 25173 Content-Length: 5908 X-Keywords: Content-Type: text/plain; charset=iso-8859-1 X-Evolution-Source: imap://jiez@mail.scs.gmu.edu/ X-Evolution: 00000008-0051 I have also checked the event 22 (October 22, 1999). Interplanetary signature: I agree with Ian that it's an ICME interacting with the fast flow from a coronal hole. Note that this ICME has signatures of an over-expanding ICME: enhanced density and magnetic field at the front and at the end, with a possible fast reverse shock right after 6:00 on Oct. 22. But this may be due to the compression of the ICME's rear part by the following fast stream. I'm not sure if it is a magnetic cloud, but if so, it should be of the NWS type. Following coronal hole has N polarity. Solar source: I fully agree with Nariaki. A partial halo CME (not reported in any catalogue) is first barely seen above the LASCO C2 occulter at 23:50 on Oct. 17, above the SSE limb. At the same time another CME (narrow, 87 deg width, PA 40 according to Gopal's catalogue) appears above the NE limb. However, these are TWO different CMEs as can be seen in running difference images around 6:50 Oct. 18. A relatively narrow bright CME is above the NE limb, and a weak partial halo spans the solar limb from ENE to SSW. Above the ENE limb it overlaps with quasi-radial structures of the narrow CME. At 23:11 EIT shows two simultaneous eruptions: at S28E11 and N05E37 (coordinates only to guide the eye, both regions are quite extended). Both have very clear dimmings (see running difference movie at ftp://omaftp.oma.be/pub/astro/andreiz/CDAW/EIT195_19991017-18.gif), the southern one has also a post-eruption arcade and the heated erupting filament matter. This unambiguously demonstrates the occurrence of a CME. The simultaneity of two eruptions (as far as we can determine with the limited EIT temporal cadence) makes me think that they represent signatures of one large-scale eruption which is visible as a partial halo CME by C2. SXT and EIT 284 data suggest that these two regions are magnetically connected. I don't think that these two eruption centers correspond to two CMEs seen by LASCO. LASCO shows the erupted matter predominantly above the NE limb and the partial halo is very weak. On the contrary, EIT data suggests that the most of the plasma was erupted from the southern source region. It seems that the narrow CME above the NE limb is a backside one - EIT shows no more eruptive signatures around this time. This event demonstrates that sometimes EIT can show more obvious CME signatures than LASCO. A space weather forecaster could miss such a weak partial halo CME, and such a severe storm may be unpredicted! Additionally, it suggests that it may be not correct to talk about a single localized CME source region. Andrei. On Friday 04 March 2005 06:31, Nariaki Nitta wrote: > Hello Ian, > > Thank you for the message, which clarified lots of things, together with > the informative plots of ACE data (with Dst). > > Indeed I see in SXT data > (http://www.lmsal.com/nitta/movies/sxt_almg_19991017_09/SXT_AlMg_19991017_0 >9.html) a global coronal restructuring between 17-Oct-1999 22 UT and > 18-Oct-1999 03 UT (between a long data gap). The EIT daily MPEG movie at > NRL > (http://lasco-www.nrl.navy.mil/daily_mpg/1999_10/991017_195.mpg) also > shows corresponding large-scale changes and an eruption from a southern > region at 23:11 (see also > http://www.lmsal.com/nitta/movies/eit_19971017_18/EIT195_19991017_18.html). > Note that these locations are far from the active region (AR 8731) > responsible for the 20-Oct-1999 filament eruption and the perhaps > associated slow CME. It is just west of the coronal hole that provided > the high speed stream as you wrote. Note that Jie's latest list > (http://cdaw.gsfc.nasa.gov/geomag_cdaw/data/cdaw1/Zhang_source/Data_Sun_Sou >rce_Zhang.html) mentions a CME at "1998/10/18 01:26 PA: 135; C2; C3 (not in > catalog)." I presume it is 1999/10/18. It would be beneficial if someone > produces a LASCO movie around this time. > > This particular event indicates the need for collaborations of experts > of various distances from the solar surface just to identify the origin > of some of the storms. > > Good night, > > Nariaki > > Ian Richardson wrote on 03.03.2005 20:35: > > Hi Nariaki, > > > > Oh yes, that event! My take is that this is a high-speed stream that is > > interacting with an ICME. The interface betweeh the two structures may > > be at ~6 UT on Oct 22, although ICME-like plasma composition (e.g., > > enhanced O7/O6, Fe charge states) does appear to persist to ~12 UT. The > > exceptionally strong storm presumably arises from the strong southward > > field in the structured) ICME, possibly enhanced by compression of the > > ICME magnetic field by the interaction with the high-speed stream. > > > > Anyone else have an opinion? > > > > The slow CME can probably be ruled out as the source of the ICME refered > > to above. The ICME has arrived at Earth by ~8 UT on October 21. This > > is only 26 hours after the CME, implying a high transit speed of ~1625 > > km/s. This seems incompatible with the slow (327 km/s) CME at the Sun > > and the modest (<~500 km/s) in-situ speed of the ICME. (Furthermore, the > > associated ICME-driven shock arrived even (~6 hours) earlier!) In > > addition, my impression is that the EIT activity associated with this > > CME was towards the west limb, (so the "E15" location is surprising) and > > that the CME rises above the west limb. I suspect that this CME was > > probably not directed towards the Earth. > > > > I would imagine that the true source of the ICME would be reasonably > > close to central meridian ~3-4 days prior to October 21, i.e. around > > October 17-18, perhaps in the same AR as that producing the October 20 > > CME. > > > > EIT 284 A observations do show a small near-equatorial coronal hole at ~ > > central meridian on October 21 that presumably could be the source of > > the high-speed stream. > > > > Regards, > > > > Ian From David.Webb@hanscom.af.mil Fri Mar 4 10:15:17 2005 Return-Path: Received: from fsmxrd02.hanscom.af.mil (thunderbird.hanscom.af.mil [129.53.219.254]) by sv01.scs.gmu.edu (8.13.1/8.12.8) with ESMTP id j24FFH53008196 for ; Fri, 4 Mar 2005 10:15:17 -0500 Received: by fsmxrd02.hanscom.af.mil with Internet Mail Service (5.5.2657.72) id ; Fri, 4 Mar 2005 10:15:11 -0500 Message-ID: <010F73C38C145744BAE4599B97F020E302D5B2C5@ml66sc-mb-05.hanscom.af.mil> From: Webb David F Contr AFRL/VSBX To: "'Ian Richardson'" , Nariaki Nitta Cc: "'jukozyra@engin.umich.edu'" , Alejandro Lara , Alexander Nindos , Andrei Zhukov , Angelos Vourlidas , Barbara Thompson , Chin-Chun Wu , Christophe Marque , Daniel Berdichevsky , Doug Biesecker , Cliver Edward W Civ AFRL/VSBXS , Emilia Huttunen , Georgoulis Manolis , Hong Xie , Jie Zhang , John Steinberg , Justin Kasper , Nat Gopalswamy , Robert MacDowall , Ryuho Kataoka , Seiji Yashiro , Vasyl Yurchyshyn , Volker Bothmer , Yang Liu Subject: RE: superstorms? Date: Fri, 4 Mar 2005 10:15:10 -0500 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2657.72) Status: O X-UID: 25183 Content-Length: 6561 X-Keywords: Content-Type: text/plain; charset=iso-8859-1 X-Evolution-Source: imap://jiez@mail.scs.gmu.edu/ X-Evolution: 0000000a-0010 Dear Ian and Nariaki, This effort shows how much work it can be to nail down soem of these events! However on this one you are somewhat reinventing the wheel. This event was one during the Space Weather Month campaign run by Janet Kozyra which was meant to only be for Sept. 1999 but brought in Oct. when this geoeffective event occurred. I was responsible for the solar-IP data and had Ron Lepping work on it. We concluded what Ian does- a complex event with an ICME and HSS. Actually both the Sept. and Oct. events show similarities and differences worth noting in our group. The Campaign has a website but I guess sonly the Sept. data appears there: http://data.engin.umich.edu/intl_space_weather/sramp/sept99_campaign_index.html There was also a session at the SRAMP meeting in Japan in 2000 which I attended. Ron produced a prentation on these events but couldn't go so I gave it. I will upload that present., if I can find it and it is more than VGs, to my dir. Regards, Dave -----Original Message----- From: Ian Richardson [mailto:richardson@lheavx.gsfc.nasa.gov] Sent: Thursday, March 03, 2005 11:35 PM To: Nariaki Nitta Cc: Webb David F Contr AFRL/VSBX; 'jukozyra@engin.umich.edu'; Alejandro Lara; Alexander Nindos; Andrei Zhukov; Angelos Vourlidas; Barbara Thompson; Chin-Chun Wu; Christophe Marque; Daniel Berdichevsky; Doug Biesecker; Cliver Edward W Civ AFRL/VSBXS; Emilia Huttunen; Georgoulis Manolis; Hong Xie; Jie Zhang; John Steinberg; Justin Kasper; Nat Gopalswamy; Robert MacDowall; Ryuho Kataoka; Seiji Yashiro; Vasyl Yurchyshyn; Volker Bothmer; Yang Liu Subject: Re: superstorms? Hi Nariaki, Oh yes, that event! My take is that this is a high-speed stream that is interacting with an ICME. The interface betweeh the two structures may be at ~6 UT on Oct 22, although ICME-like plasma composition (e.g., enhanced O7/O6, Fe charge states) does appear to persist to ~12 UT. The exceptionally strong storm presumably arises from the strong southward field in the structured) ICME, possibly enhanced by compression of the ICME magnetic field by the interaction with the high-speed stream. Anyone else have an opinion? The slow CME can probably be ruled out as the source of the ICME refered to above. The ICME has arrived at Earth by ~8 UT on October 21. This is only 26 hours after the CME, implying a high transit speed of ~1625 km/s. This seems incompatible with the slow (327 km/s) CME at the Sun and the modest (<~500 km/s) in-situ speed of the ICME. (Furthermore, the associated ICME-driven shock arrived even (~6 hours) earlier!) In addition, my impression is that the EIT activity associated with this CME was towards the west limb, (so the "E15" location is surprising) and that the CME rises above the west limb. I suspect that this CME was probably not directed towards the Earth. I would imagine that the true source of the ICME would be reasonably close to central meridian ~3-4 days prior to October 21, i.e. around October 17-18, perhaps in the same AR as that producing the October 20 CME. EIT 284 A observations do show a small near-equatorial coronal hole at ~ central meridian on October 21 that presumably could be the source of the high-speed stream. Regards, Ian At 07:26 PM 3/3/2005, Nariaki Nitta wrote: >And No. 22 is a difficult case, isn't it? Jie's list shows a CIR (can it >be the source of a superstorm?), and Nat's list shows a slow CME >(20-Oct-1999 06 UT) perhaps associated with a minor filament eruption. >TRACE data (e.g., >http://www.lmsal.com/nitta/movies/19991020_05/trace195/TRACE195_991020_05.html) >indicate a reluctant filament eruption.... > >Regards >Nariaki > > > >Ian Richardson wrote on 03.03.2005 15:00: > >>No events before no. 22 - presumably consistent with the the previously >>reported tendency for particularly energetic events (SEPs, GLEs, Forbush >>decreases, fast CMEs/ICMEs, etc) generally to occur more frequently >>following, rather than before, solar maximum. >> >>At 04:17 PM 3/3/2005, Webb David F Contr AFRL/VSBX wrote: >> >>>Jie, >>>I suggest you label these particular storms in our list. They are >>>numbers 22, 25, 27, 37, 38, 47, 68, 69, 70, 7-10 Nov. 2004 (yet to be >>>added and a big reason to add it!). Apparently there are none before No. >>>22 in our list that qualify. >>> >>>Regards, >>>Dave >>> >>>-----Original Message----- >>>From: jukozyra@engin.umich.edu [mailto:jukozyra@engin.umich.edu] >>>Sent: Thursday, March 03, 2005 4:03 PM >>>To: Webb David F Contr AFRL/VSBX >>>Subject: Re: superstorms? >>> >>> >>>Hi Dave, >>> >>>I won't be at the CDAW, Mike Liemohn is representing our group there. >>> >>>The question of "what is a superstorm?" is a good one. We are looking >>>at this >>>more carefully now for a presentation in Toulouse this summer. >>>However, in the >>>past I have been using Dst<-240 nT from Mac-Mahon et al., JGR 102, >>>14199, 1997. >>> Another paper, which Susan Gussenhoven participated in, uses 4 different >>>magnetic indices (ap, Kp, AE and Dst) to pick out the top 2% of severe >>>magnetic storms [Bell et al.,JGR, 14189, 1997]. >>> >>>My list of superstorms since 1999 based on Dst* (ring current strength) >>>includes: >>> >>>22-23 Oct 1999 >>>6-7 April 2000 >>>15-16 July 2000 >>>31 March - 1 April 2001 (double-peaked) >>>11-12 April 2001 >>>6-7 Nov 2001 >>>29-31 Oct 2003 (double-peaked) >>>20-21 Nov 2003 >>>7-10 Nov 2004 (double-peaked) >>> >>>If I can be of any other help, let me know. >>> >>>Regards, >>>Janet >>> >>> >>> >>> >>>This is actually from a paper by >>> >>>Quoting Webb David F Contr AFRL/VSBX : >>> >>> > Janet, >>> > I don't know if you are going to the Storm CDAW in 2 weeks, but we are >>> > studying the 77 storms with Dst < -100 nT. We have discussed >>> analyzing the >>> > solar inputs for superstorms and this is a good opportunity. Can you >>> provide >>> > me with a dsfinition of a superstorm, eg, is it just the Dst level or >>> > sonething more, and a sublist of superstorms from the CDAW list ?: >>> > http://cdaw.gsfc.nasa.gov/geomag_cdaw/Data.html >>> > >>> > Thanks, >>> > Regards, >>> > Dave >>> > >>> > >>> > David F. Webb >>> > AFRL/VSBXS & ISR; Boston College >>> > 29 Randolph Road >>> > Hanscom AFB, MA 01731-3010 >>> > Tel.: 781-377-3086 Fax: 781-377-3160 >>> > E-mail: david.webb@hanscom.af.mil >>> > URL(updated 2003): http://www2.bc.edu/~webbd >>> > >> >>-- >>Ian Richardson >>Code 661, GSFC, Greenbelt, MD 20771 (Building 2, Rm 25) >>Tel: 301-286-3079; Fax: 301-286-1682; > > From David.Webb@hanscom.af.mil Fri Mar 4 10:01:46 2005 Return-Path: Received: from fsmxrd02.hanscom.af.mil (thunderbird.hanscom.af.mil [129.53.219.254]) by sv01.scs.gmu.edu (8.13.1/8.12.8) with ESMTP id j24F1kBn008102 for ; Fri, 4 Mar 2005 10:01:46 -0500 Received: by fsmxrd02.hanscom.af.mil with Internet Mail Service (5.5.2657.72) id ; Fri, 4 Mar 2005 10:01:41 -0500 Message-ID: <010F73C38C145744BAE4599B97F020E302D5B2C4@ml66sc-mb-05.hanscom.af.mil> From: Webb David F Contr AFRL/VSBX To: "'jiez@scs.gmu.edu'" Subject: RE: superstorms? Date: Fri, 4 Mar 2005 10:01:40 -0500 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2657.72) Status: O X-UID: 25180 Content-Length: 4400 X-Keywords: Content-Type: text/plain; charset=iso-8859-1 X-Evolution-Source: imap://jiez@mail.scs.gmu.edu/ X-Evolution: 0000000c-0111 Jie, OK, but incl. No. 22 with an *, despite its peak being <240. Janet had other criteria for superstorms. I see my xls file ia already in my dir. I would add to the link name (at the bottom of the page) that these are sources of the full halo CMEs; the storms assoc. are alos only for the full halos. The movie links seems to work fine so I will put the other SMEI data there soon. Thanks, Dave -----Original Message----- From: Jie Zhang [mailto:jiez@scs.gmu.edu] Sent: Thursday, March 03, 2005 6:11 PM To: Webb David F Contr AFRL/VSBX Subject: RE: superstorms? You can see it at the GMU site (the working site) at "http://solar.scs.gmu.edu/meetings/cdaw/Data.html". Seiji mirror this site to GSFC (the official site) on a daily basis. By the way, could you also upload your source list (.xls) file you sent us earlier into your directory. Thanks. -Jie On Thu, 2005-03-03 at 17:51, Webb David F Contr AFRL/VSBX wrote: > Thanks but I don't see it (yet?) > Dave > > -----Original Message----- > From: Jie Zhang [mailto:jiez@scs.gmu.edu] > Sent: Thursday, March 03, 2005 5:05 PM > To: Webb David F Contr AFRL/VSBX > Cc: 'jukozyra@engin.umich.edu'; Alejandro Lara; Alexander Nindos; Andrei > Zhukov; Angelos Vourlidas; Barbara Thompson; Chin-Chun Wu; Christophe > Marque; Daniel Berdichevsky; Doug Biesecker; Cliver Edward W Civ > AFRL/VSBXS; Emilia Huttunen; Georgoulis Manolis; Hong Xie; Ian > Richardson; John Steinberg; Justin Kasper; Nariaki Nitta; Nat > Gopalswamy; Robert MacDowall; Ryuho Kataoka; Seiji Yashiro; Vasyl > Yurchyshyn; Volker Bothmer; Yang Liu > Subject: RE: superstorms? > > > Done it. They are labelled as "*" in the master table, first column, > using "-240" as threshold. Thanks. -Jie > > > On Thu, 2005-03-03 at 16:17, Webb David F Contr AFRL/VSBX wrote: > > Thanks Janet, this will be a big help. Maybe now we can make progress on the important solar-solar wind drivers of such storms. Let me know if and what specific parameters you or Mike are interested in. > > > > Jie, > > I suggest you label these particular storms in our list. They are numbers 22, 25, 27, 37, 38, 47, 68, 69, 70, 7-10 Nov. 2004 (yet to be added and a big reason to add it!). Apparently there are none before No. 22 in our list that qualify. > > > > Regards, > > Dave > > > > -----Original Message----- > > From: jukozyra@engin.umich.edu [mailto:jukozyra@engin.umich.edu] > > Sent: Thursday, March 03, 2005 4:03 PM > > To: Webb David F Contr AFRL/VSBX > > Subject: Re: superstorms? > > > > > > Hi Dave, > > > > I won't be at the CDAW, Mike Liemohn is representing our group there. > > > > The question of "what is a superstorm?" is a good one. We are looking at this > > more carefully now for a presentation in Toulouse this summer. However, in the > > past I have been using Dst<-240 nT from Mac-Mahon et al., JGR 102, 14199, 1997. > > Another paper, which Susan Gussenhoven participated in, uses 4 different > > magnetic indices (ap, Kp, AE and Dst) to pick out the top 2% of severe > > magnetic storms [Bell et al.,JGR, 14189, 1997]. > > > > My list of superstorms since 1999 based on Dst* (ring current strength) > > includes: > > > > 22-23 Oct 1999 > > 6-7 April 2000 > > 15-16 July 2000 > > 31 March - 1 April 2001 (double-peaked) > > 11-12 April 2001 > > 6-7 Nov 2001 > > 29-31 Oct 2003 (double-peaked) > > 20-21 Nov 2003 > > 7-10 Nov 2004 (double-peaked) > > > > If I can be of any other help, let me know. > > > > Regards, > > Janet > > > > > > > > > > This is actually from a paper by > > > > Quoting Webb David F Contr AFRL/VSBX : > > > > > Janet, > > > I don't know if you are going to the Storm CDAW in 2 weeks, but we are > > > studying the 77 storms with Dst < -100 nT. We have discussed analyzing the > > > solar inputs for superstorms and this is a good opportunity. Can you provide > > > me with a dsfinition of a superstorm, eg, is it just the Dst level or > > > sonething more, and a sublist of superstorms from the CDAW list ?: > > > http://cdaw.gsfc.nasa.gov/geomag_cdaw/Data.html > > > > > > Thanks, > > > Regards, > > > Dave > > > > > > > > > David F. Webb > > > AFRL/VSBXS & ISR; Boston College > > > 29 Randolph Road > > > Hanscom AFB, MA 01731-3010 > > > Tel.: 781-377-3086 Fax: 781-377-3160 > > > E-mail: david.webb@hanscom.af.mil > > > URL(updated 2003): http://www2.bc.edu/~webbd > > > From jiez@scs.gmu.edu Fri Mar 4 10:57:10 2005 Return-Path: Received: from solar.scs.gmu.edu (solar.scs.gmu.edu [129.174.124.133]) (authenticated bits=0) by sv01.scs.gmu.edu (8.13.1/8.12.8) with ESMTP id j24FvAD7008540 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Fri, 4 Mar 2005 10:57:10 -0500 Subject: RE: superstorms? From: Jie Zhang Reply-To: jiez@scs.gmu.edu To: Webb David F Contr AFRL/VSBX Cc: "'Andrei Zhukov'" , Nariaki Nitta , Ian Richardson , Alejandro Lara , Alexander Nindos , Angelos Vourlidas , Barbara Thompson , Chin-Chun Wu , Christophe Marque , Daniel Berdichevsky , Doug Biesecker , Cliver Edward W Civ AFRL/VSBXS , Emilia Huttunen , Georgoulis Manolis , Hong Xie , John Steinberg , Justin Kasper , Nat Gopalswamy , Robert MacDowall , Ryuho Kataoka , Seiji Yashiro , Vasyl Yurchyshyn , Volker Bothmer , Yang Liu In-Reply-To: <010F73C38C145744BAE4599B97F020E302D5B2C6@ml66sc-mb-05.hanscom.af.mil> References: <010F73C38C145744BAE4599B97F020E302D5B2C6@ml66sc-mb-05.hanscom.af.mil> Organization: George Mason University Message-Id: <1109951798.14613.28.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.5 (1.4.5-9) Date: Fri, 04 Mar 2005 10:56:38 -0500 Content-Transfer-Encoding: 7bit Status: O X-UID: 25194 Content-Length: 7501 X-Keywords: Content-Type: text/plain; charset=us-ascii X-Evolution-Source: imap://jiez@mail.scs.gmu.edu/ X-Evolution: 0000000e-0110 Dave, this is a good idea. This can be done for a few controversial events. But I may have to do it after the workshop. -Jie On Fri, 2005-03-04 at 10:23, Webb David F Contr AFRL/VSBX wrote: > Jie, and all, > This discussion of event 22, Oct 1999, raises a problem with me. We need to somehow archive these emails relating to specific events on the website so we can retrieve them at the workshop. Perhaps you can save all the general WG1 emails in a single dir. If so, I suggest archiving all of them from several weeks ago to the present, and up to the start of the workshop. Also, this will be useful after the workshop for followup work on these events. > > What does everyone else think about this? > > Regards, > Dave > > -----Original Message----- > From: Andrei Zhukov [mailto:Andrei.Zhukov@oma.be] > Sent: Friday, March 04, 2005 8:42 AM > To: Nariaki Nitta; Ian Richardson > Cc: Webb David F Contr AFRL/VSBX; 'jukozyra@engin.umich.edu'; Alejandro > Lara; Alexander Nindos; Angelos Vourlidas; Barbara Thompson; Chin-Chun > Wu; Christophe Marque; Daniel Berdichevsky; Doug Biesecker; Cliver > Edward W Civ AFRL/VSBXS; Emilia Huttunen; Georgoulis Manolis; Hong Xie; > Jie Zhang; John Steinberg; Justin Kasper; Nat Gopalswamy; Robert > MacDowall; Ryuho Kataoka; Seiji Yashiro; Vasyl Yurchyshyn; Volker > Bothmer; Yang Liu > Subject: Re: superstorms? > > > I have also checked the event 22 (October 22, 1999). > > Interplanetary signature: I agree with Ian that it's an ICME interacting with > the fast flow from a coronal hole. Note that this ICME has signatures of an > over-expanding ICME: enhanced density and magnetic field at the front and at > the end, with a possible fast reverse shock right after 6:00 on Oct. 22. But > this may be due to the compression of the ICME's rear part by the following > fast stream. I'm not sure if it is a magnetic cloud, but if so, it should be > of the NWS type. Following coronal hole has N polarity. > > Solar source: I fully agree with Nariaki. A partial halo CME (not reported in > any catalogue) is first barely seen above the LASCO C2 occulter at 23:50 on > Oct. 17, above the SSE limb. At the same time another CME (narrow, 87 deg > width, PA 40 according to Gopal's catalogue) appears above the NE limb. > However, these are TWO different CMEs as can be seen in running difference > images around 6:50 Oct. 18. A relatively narrow bright CME is above the NE > limb, and a weak partial halo spans the solar limb from ENE to SSW. Above the > ENE limb it overlaps with quasi-radial structures of the narrow CME. > > At 23:11 EIT shows two simultaneous eruptions: at S28E11 and N05E37 > (coordinates only to guide the eye, both regions are quite extended). Both > have very clear dimmings (see running difference movie at > ftp://omaftp.oma.be/pub/astro/andreiz/CDAW/EIT195_19991017-18.gif), the > southern one has also a post-eruption arcade and the heated erupting filament > matter. This unambiguously demonstrates the occurrence of a CME. The > simultaneity of two eruptions (as far as we can determine with the limited > EIT temporal cadence) makes me think that they represent signatures of one > large-scale eruption which is visible as a partial halo CME by C2. SXT and > EIT 284 data suggest that these two regions are magnetically connected. > > I don't think that these two eruption centers correspond to two CMEs seen by > LASCO. LASCO shows the erupted matter predominantly above the NE limb and the > partial halo is very weak. On the contrary, EIT data suggests that the most > of the plasma was erupted from the southern source region. It seems that the > narrow CME above the NE limb is a backside one - EIT shows no more eruptive > signatures around this time. > > This event demonstrates that sometimes EIT can show more obvious CME > signatures than LASCO. A space weather forecaster could miss such a weak > partial halo CME, and such a severe storm may be unpredicted! Additionally, > it suggests that it may be not correct to talk about a single localized CME > source region. > > Andrei. > > > On Friday 04 March 2005 06:31, Nariaki Nitta wrote: > > Hello Ian, > > > > Thank you for the message, which clarified lots of things, together with > > the informative plots of ACE data (with Dst). > > > > Indeed I see in SXT data > > (http://www.lmsal.com/nitta/movies/sxt_almg_19991017_09/SXT_AlMg_19991017_0 > >9.html) a global coronal restructuring between 17-Oct-1999 22 UT and > > 18-Oct-1999 03 UT (between a long data gap). The EIT daily MPEG movie at > > NRL > > (http://lasco-www.nrl.navy.mil/daily_mpg/1999_10/991017_195.mpg) also > > shows corresponding large-scale changes and an eruption from a southern > > region at 23:11 (see also > > http://www.lmsal.com/nitta/movies/eit_19971017_18/EIT195_19991017_18.html). > > Note that these locations are far from the active region (AR 8731) > > responsible for the 20-Oct-1999 filament eruption and the perhaps > > associated slow CME. It is just west of the coronal hole that provided > > the high speed stream as you wrote. Note that Jie's latest list > > (http://cdaw.gsfc.nasa.gov/geomag_cdaw/data/cdaw1/Zhang_source/Data_Sun_Sou > >rce_Zhang.html) mentions a CME at "1998/10/18 01:26 PA: 135; C2; C3 (not in > > catalog)." I presume it is 1999/10/18. It would be beneficial if someone > > produces a LASCO movie around this time. > > > > This particular event indicates the need for collaborations of experts > > of various distances from the solar surface just to identify the origin > > of some of the storms. > > > > Good night, > > > > Nariaki > > > > Ian Richardson wrote on 03.03.2005 20:35: > > > Hi Nariaki, > > > > > > Oh yes, that event! My take is that this is a high-speed stream that is > > > interacting with an ICME. The interface betweeh the two structures may > > > be at ~6 UT on Oct 22, although ICME-like plasma composition (e.g., > > > enhanced O7/O6, Fe charge states) does appear to persist to ~12 UT. The > > > exceptionally strong storm presumably arises from the strong southward > > > field in the structured) ICME, possibly enhanced by compression of the > > > ICME magnetic field by the interaction with the high-speed stream. > > > > > > Anyone else have an opinion? > > > > > > The slow CME can probably be ruled out as the source of the ICME refered > > > to above. The ICME has arrived at Earth by ~8 UT on October 21. This > > > is only 26 hours after the CME, implying a high transit speed of ~1625 > > > km/s. This seems incompatible with the slow (327 km/s) CME at the Sun > > > and the modest (<~500 km/s) in-situ speed of the ICME. (Furthermore, the > > > associated ICME-driven shock arrived even (~6 hours) earlier!) In > > > addition, my impression is that the EIT activity associated with this > > > CME was towards the west limb, (so the "E15" location is surprising) and > > > that the CME rises above the west limb. I suspect that this CME was > > > probably not directed towards the Earth. > > > > > > I would imagine that the true source of the ICME would be reasonably > > > close to central meridian ~3-4 days prior to October 21, i.e. around > > > October 17-18, perhaps in the same AR as that producing the October 20 > > > CME. > > > > > > EIT 284 A observations do show a small near-equatorial coronal hole at ~ > > > central meridian on October 21 that presumably could be the source of > > > the high-speed stream. > > > > > > Regards, > > > > > > Ian From jiez@scs.gmu.edu Thu Mar 3 17:05:52 2005 Return-Path: Received: from solar.scs.gmu.edu (solar.scs.gmu.edu [129.174.124.133]) (authenticated bits=0) by sv01.scs.gmu.edu (8.13.1/8.12.8) with ESMTP id j23M5mFh020877 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Thu, 3 Mar 2005 17:05:52 -0500 Subject: RE: superstorms? From: Jie Zhang Reply-To: jiez@scs.gmu.edu To: Webb David F Contr AFRL/VSBX Cc: "'jukozyra@engin.umich.edu'" , Alejandro Lara , Alexander Nindos , Andrei Zhukov , Angelos Vourlidas , Barbara Thompson , Chin-Chun Wu , Christophe Marque , Daniel Berdichevsky , Doug Biesecker , Ed Cliver , Emilia Huttunen , Georgoulis Manolis , Hong Xie , Ian Richardson , John Steinberg , Justin Kasper , Nariaki Nitta , Nat Gopalswamy , Robert MacDowall , Ryuho Kataoka , Seiji Yashiro , Vasyl Yurchyshyn , Volker Bothmer , Yang Liu In-Reply-To: <010F73C38C145744BAE4599B97F020E302D5B2BC@ml66sc-mb-05.hanscom.af.mil> References: <010F73C38C145744BAE4599B97F020E302D5B2BC@ml66sc-mb-05.hanscom.af.mil> Content-Type: text/plain Organization: George Mason University Message-Id: <1109887517.13423.4.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.5 (1.4.5-9) Date: Thu, 03 Mar 2005 17:05:17 -0500 Content-Transfer-Encoding: 7bit Status: RO X-UID: 25123 Content-Length: 2637 X-Keywords: X-Evolution-Source: imap://jiez@mail.scs.gmu.edu/ X-Evolution: 00000010-0010 Done it. They are labelled as "*" in the master table, first column, using "-240" as threshold. Thanks. -Jie On Thu, 2005-03-03 at 16:17, Webb David F Contr AFRL/VSBX wrote: > Thanks Janet, this will be a big help. Maybe now we can make progress on the important solar-solar wind drivers of such storms. Let me know if and what specific parameters you or Mike are interested in. > > Jie, > I suggest you label these particular storms in our list. They are numbers 22, 25, 27, 37, 38, 47, 68, 69, 70, 7-10 Nov. 2004 (yet to be added and a big reason to add it!). Apparently there are none before No. 22 in our list that qualify. > > Regards, > Dave > > -----Original Message----- > From: jukozyra@engin.umich.edu [mailto:jukozyra@engin.umich.edu] > Sent: Thursday, March 03, 2005 4:03 PM > To: Webb David F Contr AFRL/VSBX > Subject: Re: superstorms? > > > Hi Dave, > > I won't be at the CDAW, Mike Liemohn is representing our group there. > > The question of "what is a superstorm?" is a good one. We are looking at this > more carefully now for a presentation in Toulouse this summer. However, in the > past I have been using Dst<-240 nT from Mac-Mahon et al., JGR 102, 14199, 1997. > Another paper, which Susan Gussenhoven participated in, uses 4 different > magnetic indices (ap, Kp, AE and Dst) to pick out the top 2% of severe > magnetic storms [Bell et al.,JGR, 14189, 1997]. > > My list of superstorms since 1999 based on Dst* (ring current strength) > includes: > > 22-23 Oct 1999 > 6-7 April 2000 > 15-16 July 2000 > 31 March - 1 April 2001 (double-peaked) > 11-12 April 2001 > 6-7 Nov 2001 > 29-31 Oct 2003 (double-peaked) > 20-21 Nov 2003 > 7-10 Nov 2004 (double-peaked) > > If I can be of any other help, let me know. > > Regards, > Janet > > > > > This is actually from a paper by > > Quoting Webb David F Contr AFRL/VSBX : > > > Janet, > > I don't know if you are going to the Storm CDAW in 2 weeks, but we are > > studying the 77 storms with Dst < -100 nT. We have discussed analyzing the > > solar inputs for superstorms and this is a good opportunity. Can you provide > > me with a dsfinition of a superstorm, eg, is it just the Dst level or > > sonething more, and a sublist of superstorms from the CDAW list ?: > > http://cdaw.gsfc.nasa.gov/geomag_cdaw/Data.html > > > > Thanks, > > Regards, > > Dave > > > > > > David F. Webb > > AFRL/VSBXS & ISR; Boston College > > 29 Randolph Road > > Hanscom AFB, MA 01731-3010 > > Tel.: 781-377-3086 Fax: 781-377-3160 > > E-mail: david.webb@hanscom.af.mil > > URL(updated 2003): http://www2.bc.edu/~webbd > > From David.Webb@hanscom.af.mil Thu Mar 3 17:51:24 2005 Return-Path: Received: from FSMXRD01.hanscom.af.mil (thunderbird.hanscom.af.mil [129.53.219.254]) by sv01.scs.gmu.edu (8.13.1/8.12.8) with ESMTP id j23MpOMI021628 for ; Thu, 3 Mar 2005 17:51:24 -0500 Received: by fsmxrd01.hanscom.af.mil with Internet Mail Service (5.5.2657.72) id ; Thu, 3 Mar 2005 17:51:18 -0500 Message-ID: <010F73C38C145744BAE4599B97F020E302D5B2C1@ml66sc-mb-05.hanscom.af.mil> From: Webb David F Contr AFRL/VSBX To: "'jiez@scs.gmu.edu'" Subject: RE: superstorms? Date: Thu, 3 Mar 2005 17:51:16 -0500 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2657.72) Content-Type: text/plain; charset="iso-8859-1" Status: RO X-UID: 25132 Content-Length: 3281 X-Status: A X-Keywords: X-Evolution-Source: imap://jiez@mail.scs.gmu.edu/ X-Evolution: 00000012-0011 Thanks but I don't see it (yet?) Dave -----Original Message----- From: Jie Zhang [mailto:jiez@scs.gmu.edu] Sent: Thursday, March 03, 2005 5:05 PM To: Webb David F Contr AFRL/VSBX Cc: 'jukozyra@engin.umich.edu'; Alejandro Lara; Alexander Nindos; Andrei Zhukov; Angelos Vourlidas; Barbara Thompson; Chin-Chun Wu; Christophe Marque; Daniel Berdichevsky; Doug Biesecker; Cliver Edward W Civ AFRL/VSBXS; Emilia Huttunen; Georgoulis Manolis; Hong Xie; Ian Richardson; John Steinberg; Justin Kasper; Nariaki Nitta; Nat Gopalswamy; Robert MacDowall; Ryuho Kataoka; Seiji Yashiro; Vasyl Yurchyshyn; Volker Bothmer; Yang Liu Subject: RE: superstorms? Done it. They are labelled as "*" in the master table, first column, using "-240" as threshold. Thanks. -Jie On Thu, 2005-03-03 at 16:17, Webb David F Contr AFRL/VSBX wrote: > Thanks Janet, this will be a big help. Maybe now we can make progress on the important solar-solar wind drivers of such storms. Let me know if and what specific parameters you or Mike are interested in. > > Jie, > I suggest you label these particular storms in our list. They are numbers 22, 25, 27, 37, 38, 47, 68, 69, 70, 7-10 Nov. 2004 (yet to be added and a big reason to add it!). Apparently there are none before No. 22 in our list that qualify. > > Regards, > Dave > > -----Original Message----- > From: jukozyra@engin.umich.edu [mailto:jukozyra@engin.umich.edu] > Sent: Thursday, March 03, 2005 4:03 PM > To: Webb David F Contr AFRL/VSBX > Subject: Re: superstorms? > > > Hi Dave, > > I won't be at the CDAW, Mike Liemohn is representing our group there. > > The question of "what is a superstorm?" is a good one. We are looking at this > more carefully now for a presentation in Toulouse this summer. However, in the > past I have been using Dst<-240 nT from Mac-Mahon et al., JGR 102, 14199, 1997. > Another paper, which Susan Gussenhoven participated in, uses 4 different > magnetic indices (ap, Kp, AE and Dst) to pick out the top 2% of severe > magnetic storms [Bell et al.,JGR, 14189, 1997]. > > My list of superstorms since 1999 based on Dst* (ring current strength) > includes: > > 22-23 Oct 1999 > 6-7 April 2000 > 15-16 July 2000 > 31 March - 1 April 2001 (double-peaked) > 11-12 April 2001 > 6-7 Nov 2001 > 29-31 Oct 2003 (double-peaked) > 20-21 Nov 2003 > 7-10 Nov 2004 (double-peaked) > > If I can be of any other help, let me know. > > Regards, > Janet > > > > > This is actually from a paper by > > Quoting Webb David F Contr AFRL/VSBX : > > > Janet, > > I don't know if you are going to the Storm CDAW in 2 weeks, but we are > > studying the 77 storms with Dst < -100 nT. We have discussed analyzing the > > solar inputs for superstorms and this is a good opportunity. Can you provide > > me with a dsfinition of a superstorm, eg, is it just the Dst level or > > sonething more, and a sublist of superstorms from the CDAW list ?: > > http://cdaw.gsfc.nasa.gov/geomag_cdaw/Data.html > > > > Thanks, > > Regards, > > Dave > > > > > > David F. Webb > > AFRL/VSBXS & ISR; Boston College > > 29 Randolph Road > > Hanscom AFB, MA 01731-3010 > > Tel.: 781-377-3086 Fax: 781-377-3160 > > E-mail: david.webb@hanscom.af.mil > > URL(updated 2003): http://www2.bc.edu/~webbd > > From nitta@lmsal.com Fri Mar 4 01:31:19 2005 Return-Path: Received: from lmsal.com (mail.lmsal.com [198.116.7.6]) by sv01.scs.gmu.edu (8.13.1/8.12.8) with ESMTP id j246VI2L026773 for ; Fri, 4 Mar 2005 01:31:19 -0500 Received: from [198.116.7.1] (account nitta HELO [198.62.143.100]) by lmsal.com (CommuniGate Pro SMTP 4.2.9) with ESMTP-TLS id 3022256; Thu, 03 Mar 2005 22:31:12 -0800 Message-ID: <422800B0.4020503@lmsal.com> Date: Thu, 03 Mar 2005 22:31:12 -0800 From: Nariaki Nitta User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.7.2) Gecko/20040804 Netscape/7.2 (ax) X-Accept-Language: en, pdf, ja MIME-Version: 1.0 To: Ian Richardson CC: Webb David F Contr AFRL/VSBX , "'jukozyra@engin.umich.edu'" , Alejandro Lara , Alexander Nindos , Andrei Zhukov , Angelos Vourlidas , Barbara Thompson , Chin-Chun Wu , Christophe Marque , Daniel Berdichevsky , Doug Biesecker , Ed Cliver , Emilia Huttunen , Georgoulis Manolis , Hong Xie , Jie Zhang , John Steinberg , Justin Kasper , Nat Gopalswamy , Robert MacDowall , Ryuho Kataoka , Seiji Yashiro , Vasyl Yurchyshyn , Volker Bothmer , Yang Liu Subject: Re: superstorms? References: <010F73C38C145744BAE4599B97F020E302D5B2BC@ml66sc-mb-05.hanscom.af.mil> <6.1.2.0.0.20050303175210.01b46008@lheapop.gsfc.nasa.gov> <4227AB39.4020702@lmsal.com> <6.1.2.0.1.20050303223812.01da2d80@lheapop.gsfc.nasa.gov> In-Reply-To: <6.1.2.0.1.20050303223812.01da2d80@lheapop.gsfc.nasa.gov> Content-Transfer-Encoding: 7bit Status: O X-UID: 25159 Content-Length: 6799 X-Keywords: Content-Type: text/plain; charset=us-ascii; format=flowed X-Evolution-Source: imap://jiez@mail.scs.gmu.edu/ X-Evolution: 00000014-0051 Hello Ian, Thank you for the message, which clarified lots of things, together with the informative plots of ACE data (with Dst). Indeed I see in SXT data (http://www.lmsal.com/nitta/movies/sxt_almg_19991017_09/SXT_AlMg_19991017_09.html) a global coronal restructuring between 17-Oct-1999 22 UT and 18-Oct-1999 03 UT (between a long data gap). The EIT daily MPEG movie at NRL (http://lasco-www.nrl.navy.mil/daily_mpg/1999_10/991017_195.mpg) also shows corresponding large-scale changes and an eruption from a southern region at 23:11 (see also http://www.lmsal.com/nitta/movies/eit_19971017_18/EIT195_19991017_18.html). Note that these locations are far from the active region (AR 8731) responsible for the 20-Oct-1999 filament eruption and the perhaps associated slow CME. It is just west of the coronal hole that provided the high speed stream as you wrote. Note that Jie's latest list (http://cdaw.gsfc.nasa.gov/geomag_cdaw/data/cdaw1/Zhang_source/Data_Sun_Source_Zhang.html) mentions a CME at "1998/10/18 01:26 PA: 135; C2; C3 (not in catalog)." I presume it is 1999/10/18. It would be beneficial if someone produces a LASCO movie around this time. This particular event indicates the need for collaborations of experts of various distances from the solar surface just to identify the origin of some of the storms. Good night, Nariaki Ian Richardson wrote on 03.03.2005 20:35: > Hi Nariaki, > > Oh yes, that event! My take is that this is a high-speed stream that is > interacting with an ICME. The interface betweeh the two structures may > be at ~6 UT on Oct 22, although ICME-like plasma composition (e.g., > enhanced O7/O6, Fe charge states) does appear to persist to ~12 UT. The > exceptionally strong storm presumably arises from the strong southward > field in the structured) ICME, possibly enhanced by compression of the > ICME magnetic field by the interaction with the high-speed stream. > > Anyone else have an opinion? > > The slow CME can probably be ruled out as the source of the ICME refered > to above. The ICME has arrived at Earth by ~8 UT on October 21. This > is only 26 hours after the CME, implying a high transit speed of ~1625 > km/s. This seems incompatible with the slow (327 km/s) CME at the Sun > and the modest (<~500 km/s) in-situ speed of the ICME. (Furthermore, the > associated ICME-driven shock arrived even (~6 hours) earlier!) In > addition, my impression is that the EIT activity associated with this > CME was towards the west limb, (so the "E15" location is surprising) and > that the CME rises above the west limb. I suspect that this CME was > probably not directed towards the Earth. > > I would imagine that the true source of the ICME would be reasonably > close to central meridian ~3-4 days prior to October 21, i.e. around > October 17-18, perhaps in the same AR as that producing the October 20 CME. > > EIT 284 A observations do show a small near-equatorial coronal hole at ~ > central meridian on October 21 that presumably could be the source of > the high-speed stream. > > Regards, > > Ian > > > > At 07:26 PM 3/3/2005, Nariaki Nitta wrote: > >> And No. 22 is a difficult case, isn't it? Jie's list shows a CIR (can >> it be the source of a superstorm?), and Nat's list shows a slow CME >> (20-Oct-1999 06 UT) perhaps associated with a minor filament eruption. >> TRACE data (e.g., >> http://www.lmsal.com/nitta/movies/19991020_05/trace195/TRACE195_991020_05.html) >> indicate a reluctant filament eruption.... >> >> Regards >> Nariaki >> >> >> >> Ian Richardson wrote on 03.03.2005 15:00: >> >>> No events before no. 22 - presumably consistent with the the >>> previously reported tendency for particularly energetic events (SEPs, >>> GLEs, Forbush decreases, fast CMEs/ICMEs, etc) generally to occur >>> more frequently following, rather than before, solar maximum. >>> >>> At 04:17 PM 3/3/2005, Webb David F Contr AFRL/VSBX wrote: >>> >>>> Jie, >>>> I suggest you label these particular storms in our list. They are >>>> numbers 22, 25, 27, 37, 38, 47, 68, 69, 70, 7-10 Nov. 2004 (yet to >>>> be added and a big reason to add it!). Apparently there are none >>>> before No. 22 in our list that qualify. >>>> >>>> Regards, >>>> Dave >>>> >>>> -----Original Message----- >>>> From: jukozyra@engin.umich.edu [mailto:jukozyra@engin.umich.edu] >>>> Sent: Thursday, March 03, 2005 4:03 PM >>>> To: Webb David F Contr AFRL/VSBX >>>> Subject: Re: superstorms? >>>> >>>> >>>> Hi Dave, >>>> >>>> I won't be at the CDAW, Mike Liemohn is representing our group there. >>>> >>>> The question of "what is a superstorm?" is a good one. We are >>>> looking at this >>>> more carefully now for a presentation in Toulouse this summer. >>>> However, in the >>>> past I have been using Dst<-240 nT from Mac-Mahon et al., JGR 102, >>>> 14199, 1997. >>>> Another paper, which Susan Gussenhoven participated in, uses 4 >>>> different >>>> magnetic indices (ap, Kp, AE and Dst) to pick out the top 2% of severe >>>> magnetic storms [Bell et al.,JGR, 14189, 1997]. >>>> >>>> My list of superstorms since 1999 based on Dst* (ring current strength) >>>> includes: >>>> >>>> 22-23 Oct 1999 >>>> 6-7 April 2000 >>>> 15-16 July 2000 >>>> 31 March - 1 April 2001 (double-peaked) >>>> 11-12 April 2001 >>>> 6-7 Nov 2001 >>>> 29-31 Oct 2003 (double-peaked) >>>> 20-21 Nov 2003 >>>> 7-10 Nov 2004 (double-peaked) >>>> >>>> If I can be of any other help, let me know. >>>> >>>> Regards, >>>> Janet >>>> >>>> >>>> >>>> >>>> This is actually from a paper by >>>> >>>> Quoting Webb David F Contr AFRL/VSBX : >>>> >>>> > Janet, >>>> > I don't know if you are going to the Storm CDAW in 2 weeks, but we >>>> are >>>> > studying the 77 storms with Dst < -100 nT. We have discussed >>>> analyzing the >>>> > solar inputs for superstorms and this is a good opportunity. Can >>>> you provide >>>> > me with a dsfinition of a superstorm, eg, is it just the Dst level or >>>> > sonething more, and a sublist of superstorms from the CDAW list ?: >>>> > http://cdaw.gsfc.nasa.gov/geomag_cdaw/Data.html >>>> > >>>> > Thanks, >>>> > Regards, >>>> > Dave >>>> > >>>> > >>>> > David F. Webb >>>> > AFRL/VSBXS & ISR; Boston College >>>> > 29 Randolph Road >>>> > Hanscom AFB, MA 01731-3010 >>>> > Tel.: 781-377-3086 Fax: 781-377-3160 >>>> > E-mail: david.webb@hanscom.af.mil >>>> > URL(updated 2003): http://www2.bc.edu/~webbd >>>> > >>> >>> >>> -- >>> Ian Richardson >>> Code 661, GSFC, Greenbelt, MD 20771 (Building 2, Rm 25) >>> Tel: 301-286-3079; Fax: 301-286-1682; >> >> >> > > > -- Nariaki Nitta LMATC, Bldg/252, Dept/ADBS 3251 Hanover Street Palo Alto, CA 94304, USA Voice: (650)354-5458, FAX: (650)424-3994 email: nitta at lmsal.com From richardson@lheavx.gsfc.nasa.gov Fri Mar 4 11:19:59 2005 Return-Path: Received: from milkyway.gsfc.nasa.gov (milkyway.gsfc.nasa.gov [128.183.16.143]) by sv01.scs.gmu.edu (8.13.1/8.12.8) with ESMTP id j24GJx61008756 for ; Fri, 4 Mar 2005 11:19:59 -0500 Received: from Ian.lheavx.gsfc.nasa.gov (particles.gsfc.nasa.gov [128.183.19.36]) by milkyway.gsfc.nasa.gov (8.13.1/8.13.1) with ESMTP id j24GHIfR016322; Fri, 4 Mar 2005 11:17:18 -0500 Message-Id: <6.1.2.0.0.20050304105845.01b86ec0@lheapop.gsfc.nasa.gov> X-Sender: ianr@lheapop.gsfc.nasa.gov X-Mailer: QUALCOMM Windows Eudora Version 6.1.2.0 Date: Fri, 04 Mar 2005 11:15:39 -0500 To: Webb David F Contr AFRL/VSBX , Nariaki Nitta From: Ian Richardson Subject: RE: superstorms? Cc: "'jukozyra@engin.umich.edu'" , Alejandro Lara , Alexander Nindos , Andrei Zhukov , Angelos Vourlidas , Barbara Thompson , Chin-Chun Wu , Christophe Marque , Daniel Berdichevsky , Doug Biesecker , Cliver Edward W Civ AFRL/VSBXS , Emilia Huttunen , Georgoulis Manolis , Hong Xie , Jie Zhang , John Steinberg , Justin Kasper , Nat Gopalswamy , Robert MacDowall , Ryuho Kataoka , Seiji Yashiro , Vasyl Yurchyshyn , Volker Bothmer , Yang Liu In-Reply-To: <010F73C38C145744BAE4599B97F020E302D5B2C5@ml66sc-mb-05.hans com.af.mil> References: <010F73C38C145744BAE4599B97F020E302D5B2C5@ml66sc-mb-05.hanscom.af.mil> Mime-Version: 1.0 X-Scanned-By: MIMEDefang 2.49 on 128.183.16.62 Status: O X-UID: 25197 Content-Length: 7496 X-Keywords: Content-Type: text/plain; charset=us-ascii; format=flowed X-Evolution-Source: imap://jiez@mail.scs.gmu.edu/ X-Evolution: 00000016-0110 Hi Dave, The discussion brings up two particular points: 1) The workshop will bring together, in one room, a large body of expertize on these events - very encouraging! 2) We all need to try to gather together what has been done before on these events, by ourselves and others. Having not been involved with the Space Weather month, I certainly wasn't aware of your study. But at least there seems to be some unanimity in the interpretation, at least of the IP data. Regards, Ian At 10:15 AM 3/4/2005, Webb David F Contr AFRL/VSBX wrote: >Dear Ian and Nariaki, > >This effort shows how much work it can be to nail down soem of these >events! However on this one you are somewhat reinventing the wheel. This >event was one during the Space Weather Month campaign run by Janet Kozyra >which was meant to only be for Sept. 1999 but brought in Oct. when this >geoeffective event occurred. >I was responsible for the solar-IP data and had Ron Lepping work on it. We >concluded what Ian does- a complex event with an ICME and HSS. Actually >both the Sept. and Oct. events show similarities and differences worth >noting in our group. The Campaign has a website but I guess sonly the >Sept. data appears there: >http://data.engin.umich.edu/intl_space_weather/sramp/sept99_campaign_index.html >There was also a session at the SRAMP meeting in Japan in 2000 which I >attended. Ron produced a prentation on these events but couldn't go so I >gave it. I will upload that present., if I can find it and it is more than >VGs, to my dir. > >Regards, >Dave > > >-----Original Message----- >From: Ian Richardson [mailto:richardson@lheavx.gsfc.nasa.gov] >Sent: Thursday, March 03, 2005 11:35 PM >To: Nariaki Nitta >Cc: Webb David F Contr AFRL/VSBX; 'jukozyra@engin.umich.edu'; Alejandro >Lara; Alexander Nindos; Andrei Zhukov; Angelos Vourlidas; Barbara >Thompson; Chin-Chun Wu; Christophe Marque; Daniel Berdichevsky; Doug >Biesecker; Cliver Edward W Civ AFRL/VSBXS; Emilia Huttunen; Georgoulis >Manolis; Hong Xie; Jie Zhang; John Steinberg; Justin Kasper; Nat >Gopalswamy; Robert MacDowall; Ryuho Kataoka; Seiji Yashiro; Vasyl >Yurchyshyn; Volker Bothmer; Yang Liu >Subject: Re: superstorms? > > >Hi Nariaki, > >Oh yes, that event! My take is that this is a high-speed stream that is >interacting with an ICME. The interface betweeh the two structures may be >at ~6 UT on Oct 22, although ICME-like plasma composition (e.g., enhanced >O7/O6, Fe charge states) does appear to persist to ~12 UT. The >exceptionally strong storm presumably arises from the strong southward >field in the structured) ICME, possibly enhanced by compression of the ICME >magnetic field by the interaction with the high-speed stream. > >Anyone else have an opinion? > >The slow CME can probably be ruled out as the source of the ICME refered to >above. The ICME has arrived at Earth by ~8 UT on October 21. This is >only 26 hours after the CME, implying a high transit speed of ~1625 >km/s. This seems incompatible with the slow (327 km/s) CME at the Sun and >the modest (<~500 km/s) in-situ speed of the ICME. (Furthermore, the >associated ICME-driven shock arrived even (~6 hours) earlier!) In >addition, my impression is that the EIT activity associated with this CME >was towards the west limb, (so the "E15" location is surprising) and that >the CME rises above the west limb. I suspect that this CME was probably >not directed towards the Earth. > >I would imagine that the true source of the ICME would be reasonably close >to central meridian ~3-4 days prior to October 21, i.e. around October >17-18, perhaps in the same AR as that producing the October 20 CME. > >EIT 284 A observations do show a small near-equatorial coronal hole at ~ >central meridian on October 21 that presumably could be the source of the >high-speed stream. > >Regards, > >Ian > > > >At 07:26 PM 3/3/2005, Nariaki Nitta wrote: > >And No. 22 is a difficult case, isn't it? Jie's list shows a CIR (can it > >be the source of a superstorm?), and Nat's list shows a slow CME > >(20-Oct-1999 06 UT) perhaps associated with a minor filament eruption. > >TRACE data (e.g., > >http://www.lmsal.com/nitta/movies/19991020_05/trace195/TRACE195_991020_05 > .html) > >indicate a reluctant filament eruption.... > > > >Regards > >Nariaki > > > > > > > >Ian Richardson wrote on 03.03.2005 15:00: > > > >>No events before no. 22 - presumably consistent with the the previously > >>reported tendency for particularly energetic events (SEPs, GLEs, Forbush > >>decreases, fast CMEs/ICMEs, etc) generally to occur more frequently > >>following, rather than before, solar maximum. > >> > >>At 04:17 PM 3/3/2005, Webb David F Contr AFRL/VSBX wrote: > >> > >>>Jie, > >>>I suggest you label these particular storms in our list. They are > >>>numbers 22, 25, 27, 37, 38, 47, 68, 69, 70, 7-10 Nov. 2004 (yet to be > >>>added and a big reason to add it!). Apparently there are none before No. > >>>22 in our list that qualify. > >>> > >>>Regards, > >>>Dave > >>> > >>>-----Original Message----- > >>>From: jukozyra@engin.umich.edu [mailto:jukozyra@engin.umich.edu] > >>>Sent: Thursday, March 03, 2005 4:03 PM > >>>To: Webb David F Contr AFRL/VSBX > >>>Subject: Re: superstorms? > >>> > >>> > >>>Hi Dave, > >>> > >>>I won't be at the CDAW, Mike Liemohn is representing our group there. > >>> > >>>The question of "what is a superstorm?" is a good one. We are looking > >>>at this > >>>more carefully now for a presentation in Toulouse this summer. > >>>However, in the > >>>past I have been using Dst<-240 nT from Mac-Mahon et al., JGR 102, > >>>14199, 1997. > >>> Another paper, which Susan Gussenhoven participated in, uses 4 different > >>>magnetic indices (ap, Kp, AE and Dst) to pick out the top 2% of severe > >>>magnetic storms [Bell et al.,JGR, 14189, 1997]. > >>> > >>>My list of superstorms since 1999 based on Dst* (ring current strength) > >>>includes: > >>> > >>>22-23 Oct 1999 > >>>6-7 April 2000 > >>>15-16 July 2000 > >>>31 March - 1 April 2001 (double-peaked) > >>>11-12 April 2001 > >>>6-7 Nov 2001 > >>>29-31 Oct 2003 (double-peaked) > >>>20-21 Nov 2003 > >>>7-10 Nov 2004 (double-peaked) > >>> > >>>If I can be of any other help, let me know. > >>> > >>>Regards, > >>>Janet > >>> > >>> > >>> > >>> > >>>This is actually from a paper by > >>> > >>>Quoting Webb David F Contr AFRL/VSBX : > >>> > >>> > Janet, > >>> > I don't know if you are going to the Storm CDAW in 2 weeks, but we are > >>> > studying the 77 storms with Dst < -100 nT. We have discussed > >>> analyzing the > >>> > solar inputs for superstorms and this is a good opportunity. Can you > >>> provide > >>> > me with a dsfinition of a superstorm, eg, is it just the Dst level or > >>> > sonething more, and a sublist of superstorms from the CDAW list ?: > >>> > http://cdaw.gsfc.nasa.gov/geomag_cdaw/Data.html > >>> > > >>> > Thanks, > >>> > Regards, > >>> > Dave > >>> > > >>> > > >>> > David F. Webb > >>> > AFRL/VSBXS & ISR; Boston College > >>> > 29 Randolph Road > >>> > Hanscom AFB, MA 01731-3010 > >>> > Tel.: 781-377-3086 Fax: 781-377-3160 > >>> > E-mail: david.webb@hanscom.af.mil > >>> > URL(updated 2003): http://www2.bc.edu/~webbd > >>> > > >> > >>-- > >>Ian Richardson > >>Code 661, GSFC, Greenbelt, MD 20771 (Building 2, Rm 25) > >>Tel: 301-286-3079; Fax: 301-286-1682; > > > > -- Ian Richardson Code 661, GSFC, Greenbelt, MD 20771 (Building 2, Rm 25) Tel: 301-286-3079; Fax: 301-286-1682; From richardson@lheavx.gsfc.nasa.gov Thu Mar 3 18:04:39 2005 Return-Path: Received: from milkyway.gsfc.nasa.gov (milkyway.gsfc.nasa.gov [128.183.16.143]) by sv01.scs.gmu.edu (8.13.1/8.12.8) with ESMTP id j23N4dLS021846 for ; Thu, 3 Mar 2005 18:04:39 -0500 Received: from Ian.lheavx.gsfc.nasa.gov (particles.gsfc.nasa.gov [128.183.19.36]) by milkyway.gsfc.nasa.gov (8.13.1/8.13.1) with ESMTP id j23N2HdV029199; Thu, 3 Mar 2005 18:02:18 -0500 Message-Id: <6.1.2.0.0.20050303175210.01b46008@lheapop.gsfc.nasa.gov> X-Sender: ianr@lheapop.gsfc.nasa.gov X-Mailer: QUALCOMM Windows Eudora Version 6.1.2.0 Date: Thu, 03 Mar 2005 18:00:39 -0500 To: Webb David F Contr AFRL/VSBX , "'jukozyra@engin.umich.edu'" From: Ian Richardson Subject: RE: superstorms? Cc: Alejandro Lara , Alexander Nindos , Andrei Zhukov , Angelos Vourlidas , Barbara Thompson , Chin-Chun Wu , Christophe Marque , Daniel Berdichevsky , Dave Webb , Doug Biesecker , Ed Cliver , Emilia Huttunen , Georgoulis Manolis , Hong Xie , Jie Zhang , John Steinberg , Justin Kasper , Nariaki Nitta , Nat Gopalswamy , Robert MacDowall , Ryuho Kataoka , Seiji Yashiro , Vasyl Yurchyshyn , Volker Bothmer , Yang Liu In-Reply-To: <010F73C38C145744BAE4599B97F020E302D5B2BC@ml66sc-mb-05.hans com.af.mil> References: <010F73C38C145744BAE4599B97F020E302D5B2BC@ml66sc-mb-05.hanscom.af.mil> Mime-Version: 1.0 X-Scanned-By: MIMEDefang 2.49 on 128.183.16.62 Status: RO X-UID: 25137 Content-Length: 2653 X-Keywords: Content-Type: text/plain; charset=us-ascii; format=flowed X-Evolution-Source: imap://jiez@mail.scs.gmu.edu/ X-Evolution: 00000018-0010 No events before no. 22 - presumably consistent with the the previously reported tendency for particularly energetic events (SEPs, GLEs, Forbush decreases, fast CMEs/ICMEs, etc) generally to occur more frequently following, rather than before, solar maximum. At 04:17 PM 3/3/2005, Webb David F Contr AFRL/VSBX wrote: >Jie, >I suggest you label these particular storms in our list. They are numbers >22, 25, 27, 37, 38, 47, 68, 69, 70, 7-10 Nov. 2004 (yet to be added and a >big reason to add it!). Apparently there are none before No. 22 in our >list that qualify. > >Regards, >Dave > >-----Original Message----- >From: jukozyra@engin.umich.edu [mailto:jukozyra@engin.umich.edu] >Sent: Thursday, March 03, 2005 4:03 PM >To: Webb David F Contr AFRL/VSBX >Subject: Re: superstorms? > > >Hi Dave, > >I won't be at the CDAW, Mike Liemohn is representing our group there. > >The question of "what is a superstorm?" is a good one. We are looking at this >more carefully now for a presentation in Toulouse this summer. However, >in the >past I have been using Dst<-240 nT from Mac-Mahon et al., JGR 102, 14199, >1997. > Another paper, which Susan Gussenhoven participated in, uses 4 different >magnetic indices (ap, Kp, AE and Dst) to pick out the top 2% of severe >magnetic storms [Bell et al.,JGR, 14189, 1997]. > >My list of superstorms since 1999 based on Dst* (ring current strength) >includes: > >22-23 Oct 1999 >6-7 April 2000 >15-16 July 2000 >31 March - 1 April 2001 (double-peaked) >11-12 April 2001 >6-7 Nov 2001 >29-31 Oct 2003 (double-peaked) >20-21 Nov 2003 >7-10 Nov 2004 (double-peaked) > >If I can be of any other help, let me know. > >Regards, >Janet > > > > >This is actually from a paper by > >Quoting Webb David F Contr AFRL/VSBX : > > > Janet, > > I don't know if you are going to the Storm CDAW in 2 weeks, but we are > > studying the 77 storms with Dst < -100 nT. We have discussed analyzing the > > solar inputs for superstorms and this is a good opportunity. Can you > provide > > me with a dsfinition of a superstorm, eg, is it just the Dst level or > > sonething more, and a sublist of superstorms from the CDAW list ?: > > http://cdaw.gsfc.nasa.gov/geomag_cdaw/Data.html > > > > Thanks, > > Regards, > > Dave > > > > > > David F. Webb > > AFRL/VSBXS & ISR; Boston College > > 29 Randolph Road > > Hanscom AFB, MA 01731-3010 > > Tel.: 781-377-3086 Fax: 781-377-3160 > > E-mail: david.webb@hanscom.af.mil > > URL(updated 2003): http://www2.bc.edu/~webbd > > -- Ian Richardson Code 661, GSFC, Greenbelt, MD 20771 (Building 2, Rm 25) Tel: 301-286-3079; Fax: 301-286-1682; From jiez@scs.gmu.edu Fri Mar 4 10:45:08 2005 Return-Path: Received: from solar.scs.gmu.edu (solar.scs.gmu.edu [129.174.124.133]) (authenticated bits=0) by sv01.scs.gmu.edu (8.13.1/8.12.8) with ESMTP id j24Fj8mY008445 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Fri, 4 Mar 2005 10:45:08 -0500 Subject: Re: superstorms? From: Jie Zhang Reply-To: jiez@scs.gmu.edu To: Andrei Zhukov Cc: Nariaki Nitta , Ian Richardson , Webb David F Contr AFRL/VSBX , "'jukozyra@engin.umich.edu'" , Alejandro Lara , Alexander Nindos , Angelos Vourlidas , Barbara Thompson , Chin-Chun Wu , Christophe Marque , Daniel Berdichevsky , Doug Biesecker , Ed Cliver , Emilia Huttunen , Georgoulis Manolis , Hong Xie , John Steinberg , Justin Kasper , Nat Gopalswamy , Robert MacDowall , Ryuho Kataoka , Seiji Yashiro , Vasyl Yurchyshyn , Volker Bothmer , Yang Liu In-Reply-To: <200503041342.27436.Andrei.Zhukov@oma.be> References: <010F73C38C145744BAE4599B97F020E302D5B2BC@ml66sc-mb-05.hanscom.af.mil> <6.1.2.0.1.20050303223812.01da2d80@lheapop.gsfc.nasa.gov> <422800B0.4020503@lmsal.com> <200503041342.27436.Andrei.Zhukov@oma.be> Organization: George Mason University Message-Id: <1109951076.14613.16.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.5 (1.4.5-9) Date: Fri, 04 Mar 2005 10:44:36 -0500 Content-Transfer-Encoding: 7bit Status: O X-UID: 25192 Content-Length: 6205 X-Keywords: Content-Type: text/plain; charset=us-ascii X-Evolution-Source: imap://jiez@mail.scs.gmu.edu/ X-Evolution: 0000001a-0010 Fully agree. -Jie On Fri, 2005-03-04 at 08:42, Andrei Zhukov wrote: > I have also checked the event 22 (October 22, 1999). > > Interplanetary signature: I agree with Ian that it's an ICME interacting with > the fast flow from a coronal hole. Note that this ICME has signatures of an > over-expanding ICME: enhanced density and magnetic field at the front and at > the end, with a possible fast reverse shock right after 6:00 on Oct. 22. But > this may be due to the compression of the ICME's rear part by the following > fast stream. I'm not sure if it is a magnetic cloud, but if so, it should be > of the NWS type. Following coronal hole has N polarity. > > Solar source: I fully agree with Nariaki. A partial halo CME (not reported in > any catalogue) is first barely seen above the LASCO C2 occulter at 23:50 on > Oct. 17, above the SSE limb. At the same time another CME (narrow, 87 deg > width, PA 40 according to Gopal's catalogue) appears above the NE limb. > However, these are TWO different CMEs as can be seen in running difference > images around 6:50 Oct. 18. A relatively narrow bright CME is above the NE > limb, and a weak partial halo spans the solar limb from ENE to SSW. Above the > ENE limb it overlaps with quasi-radial structures of the narrow CME. > > At 23:11 EIT shows two simultaneous eruptions: at S28E11 and N05E37 > (coordinates only to guide the eye, both regions are quite extended). Both > have very clear dimmings (see running difference movie at > ftp://omaftp.oma.be/pub/astro/andreiz/CDAW/EIT195_19991017-18.gif), the > southern one has also a post-eruption arcade and the heated erupting filament > matter. This unambiguously demonstrates the occurrence of a CME. The > simultaneity of two eruptions (as far as we can determine with the limited > EIT temporal cadence) makes me think that they represent signatures of one > large-scale eruption which is visible as a partial halo CME by C2. SXT and > EIT 284 data suggest that these two regions are magnetically connected. > > I don't think that these two eruption centers correspond to two CMEs seen by > LASCO. LASCO shows the erupted matter predominantly above the NE limb and the > partial halo is very weak. On the contrary, EIT data suggests that the most > of the plasma was erupted from the southern source region. It seems that the > narrow CME above the NE limb is a backside one - EIT shows no more eruptive > signatures around this time. > > This event demonstrates that sometimes EIT can show more obvious CME > signatures than LASCO. A space weather forecaster could miss such a weak > partial halo CME, and such a severe storm may be unpredicted! Additionally, > it suggests that it may be not correct to talk about a single localized CME > source region. > > Andrei. > > > On Friday 04 March 2005 06:31, Nariaki Nitta wrote: > > Hello Ian, > > > > Thank you for the message, which clarified lots of things, together with > > the informative plots of ACE data (with Dst). > > > > Indeed I see in SXT data > > (http://www.lmsal.com/nitta/movies/sxt_almg_19991017_09/SXT_AlMg_19991017_0 > >9.html) a global coronal restructuring between 17-Oct-1999 22 UT and > > 18-Oct-1999 03 UT (between a long data gap). The EIT daily MPEG movie at > > NRL > > (http://lasco-www.nrl.navy.mil/daily_mpg/1999_10/991017_195.mpg) also > > shows corresponding large-scale changes and an eruption from a southern > > region at 23:11 (see also > > http://www.lmsal.com/nitta/movies/eit_19971017_18/EIT195_19991017_18.html). > > Note that these locations are far from the active region (AR 8731) > > responsible for the 20-Oct-1999 filament eruption and the perhaps > > associated slow CME. It is just west of the coronal hole that provided > > the high speed stream as you wrote. Note that Jie's latest list > > (http://cdaw.gsfc.nasa.gov/geomag_cdaw/data/cdaw1/Zhang_source/Data_Sun_Sou > >rce_Zhang.html) mentions a CME at "1998/10/18 01:26 PA: 135; C2; C3 (not in > > catalog)." I presume it is 1999/10/18. It would be beneficial if someone > > produces a LASCO movie around this time. > > > > This particular event indicates the need for collaborations of experts > > of various distances from the solar surface just to identify the origin > > of some of the storms. > > > > Good night, > > > > Nariaki > > > > Ian Richardson wrote on 03.03.2005 20:35: > > > Hi Nariaki, > > > > > > Oh yes, that event! My take is that this is a high-speed stream that is > > > interacting with an ICME. The interface betweeh the two structures may > > > be at ~6 UT on Oct 22, although ICME-like plasma composition (e.g., > > > enhanced O7/O6, Fe charge states) does appear to persist to ~12 UT. The > > > exceptionally strong storm presumably arises from the strong southward > > > field in the structured) ICME, possibly enhanced by compression of the > > > ICME magnetic field by the interaction with the high-speed stream. > > > > > > Anyone else have an opinion? > > > > > > The slow CME can probably be ruled out as the source of the ICME refered > > > to above. The ICME has arrived at Earth by ~8 UT on October 21. This > > > is only 26 hours after the CME, implying a high transit speed of ~1625 > > > km/s. This seems incompatible with the slow (327 km/s) CME at the Sun > > > and the modest (<~500 km/s) in-situ speed of the ICME. (Furthermore, the > > > associated ICME-driven shock arrived even (~6 hours) earlier!) In > > > addition, my impression is that the EIT activity associated with this > > > CME was towards the west limb, (so the "E15" location is surprising) and > > > that the CME rises above the west limb. I suspect that this CME was > > > probably not directed towards the Earth. > > > > > > I would imagine that the true source of the ICME would be reasonably > > > close to central meridian ~3-4 days prior to October 21, i.e. around > > > October 17-18, perhaps in the same AR as that producing the October 20 > > > CME. > > > > > > EIT 284 A observations do show a small near-equatorial coronal hole at ~ > > > central meridian on October 21 that presumably could be the source of > > > the high-speed stream. > > > > > > Regards, > > > > > > Ian From richardson@lheavx.gsfc.nasa.gov Thu Mar 3 23:37:55 2005 Return-Path: Received: from milkyway.gsfc.nasa.gov (milkyway.gsfc.nasa.gov [128.183.16.143]) by sv01.scs.gmu.edu (8.13.1/8.12.8) with ESMTP id j244bt7K026049 for ; Thu, 3 Mar 2005 23:37:55 -0500 Received: from IansLaptop.lheavx.gsfc.nasa.gov (pcp04300329pcs.anaprd01.md.comcast.net [68.49.191.97]) by milkyway.gsfc.nasa.gov (8.13.1/8.13.1) with ESMTP id j244ZFRF023818; Thu, 3 Mar 2005 23:35:26 -0500 Message-Id: <6.1.2.0.1.20050303223812.01da2d80@lheapop.gsfc.nasa.gov> X-Sender: ianr@lheapop.gsfc.nasa.gov (Unverified) X-Mailer: QUALCOMM Windows Eudora Version 6.1.2.0 Date: Thu, 03 Mar 2005 23:35:17 -0500 To: Nariaki Nitta From: Ian Richardson Subject: Re: superstorms? Cc: Webb David F Contr AFRL/VSBX , "'jukozyra@engin.umich.edu'" , Alejandro Lara , Alexander Nindos , Andrei Zhukov , Angelos Vourlidas , Barbara Thompson , Chin-Chun Wu , Christophe Marque , Daniel Berdichevsky , Doug Biesecker , Ed Cliver , Emilia Huttunen , Georgoulis Manolis , Hong Xie , Jie Zhang , John Steinberg , Justin Kasper , Nat Gopalswamy , Robert MacDowall , Ryuho Kataoka , Seiji Yashiro , Vasyl Yurchyshyn , Volker Bothmer , Yang Liu In-Reply-To: <4227AB39.4020702@lmsal.com> References: <010F73C38C145744BAE4599B97F020E302D5B2BC@ml66sc-mb-05.hanscom.af.mil> <6.1.2.0.0.20050303175210.01b46008@lheapop.gsfc.nasa.gov> <4227AB39.4020702@lmsal.com> Mime-Version: 1.0 X-Scanned-By: MIMEDefang 2.49 on 128.183.16.62 Status: O X-UID: 25157 Content-Length: 4954 X-Keywords: Content-Type: text/plain; charset=us-ascii; format=flowed X-Evolution-Source: imap://jiez@mail.scs.gmu.edu/ X-Evolution: 0000001c-0010 Hi Nariaki, Oh yes, that event! My take is that this is a high-speed stream that is interacting with an ICME. The interface betweeh the two structures may be at ~6 UT on Oct 22, although ICME-like plasma composition (e.g., enhanced O7/O6, Fe charge states) does appear to persist to ~12 UT. The exceptionally strong storm presumably arises from the strong southward field in the structured) ICME, possibly enhanced by compression of the ICME magnetic field by the interaction with the high-speed stream. Anyone else have an opinion? The slow CME can probably be ruled out as the source of the ICME refered to above. The ICME has arrived at Earth by ~8 UT on October 21. This is only 26 hours after the CME, implying a high transit speed of ~1625 km/s. This seems incompatible with the slow (327 km/s) CME at the Sun and the modest (<~500 km/s) in-situ speed of the ICME. (Furthermore, the associated ICME-driven shock arrived even (~6 hours) earlier!) In addition, my impression is that the EIT activity associated with this CME was towards the west limb, (so the "E15" location is surprising) and that the CME rises above the west limb. I suspect that this CME was probably not directed towards the Earth. I would imagine that the true source of the ICME would be reasonably close to central meridian ~3-4 days prior to October 21, i.e. around October 17-18, perhaps in the same AR as that producing the October 20 CME. EIT 284 A observations do show a small near-equatorial coronal hole at ~ central meridian on October 21 that presumably could be the source of the high-speed stream. Regards, Ian At 07:26 PM 3/3/2005, Nariaki Nitta wrote: >And No. 22 is a difficult case, isn't it? Jie's list shows a CIR (can it >be the source of a superstorm?), and Nat's list shows a slow CME >(20-Oct-1999 06 UT) perhaps associated with a minor filament eruption. >TRACE data (e.g., >http://www.lmsal.com/nitta/movies/19991020_05/trace195/TRACE195_991020_05.html) >indicate a reluctant filament eruption.... > >Regards >Nariaki > > > >Ian Richardson wrote on 03.03.2005 15:00: > >>No events before no. 22 - presumably consistent with the the previously >>reported tendency for particularly energetic events (SEPs, GLEs, Forbush >>decreases, fast CMEs/ICMEs, etc) generally to occur more frequently >>following, rather than before, solar maximum. >> >>At 04:17 PM 3/3/2005, Webb David F Contr AFRL/VSBX wrote: >> >>>Jie, >>>I suggest you label these particular storms in our list. They are >>>numbers 22, 25, 27, 37, 38, 47, 68, 69, 70, 7-10 Nov. 2004 (yet to be >>>added and a big reason to add it!). Apparently there are none before No. >>>22 in our list that qualify. >>> >>>Regards, >>>Dave >>> >>>-----Original Message----- >>>From: jukozyra@engin.umich.edu [mailto:jukozyra@engin.umich.edu] >>>Sent: Thursday, March 03, 2005 4:03 PM >>>To: Webb David F Contr AFRL/VSBX >>>Subject: Re: superstorms? >>> >>> >>>Hi Dave, >>> >>>I won't be at the CDAW, Mike Liemohn is representing our group there. >>> >>>The question of "what is a superstorm?" is a good one. We are looking >>>at this >>>more carefully now for a presentation in Toulouse this summer. >>>However, in the >>>past I have been using Dst<-240 nT from Mac-Mahon et al., JGR 102, >>>14199, 1997. >>> Another paper, which Susan Gussenhoven participated in, uses 4 different >>>magnetic indices (ap, Kp, AE and Dst) to pick out the top 2% of severe >>>magnetic storms [Bell et al.,JGR, 14189, 1997]. >>> >>>My list of superstorms since 1999 based on Dst* (ring current strength) >>>includes: >>> >>>22-23 Oct 1999 >>>6-7 April 2000 >>>15-16 July 2000 >>>31 March - 1 April 2001 (double-peaked) >>>11-12 April 2001 >>>6-7 Nov 2001 >>>29-31 Oct 2003 (double-peaked) >>>20-21 Nov 2003 >>>7-10 Nov 2004 (double-peaked) >>> >>>If I can be of any other help, let me know. >>> >>>Regards, >>>Janet >>> >>> >>> >>> >>>This is actually from a paper by >>> >>>Quoting Webb David F Contr AFRL/VSBX : >>> >>> > Janet, >>> > I don't know if you are going to the Storm CDAW in 2 weeks, but we are >>> > studying the 77 storms with Dst < -100 nT. We have discussed >>> analyzing the >>> > solar inputs for superstorms and this is a good opportunity. Can you >>> provide >>> > me with a dsfinition of a superstorm, eg, is it just the Dst level or >>> > sonething more, and a sublist of superstorms from the CDAW list ?: >>> > http://cdaw.gsfc.nasa.gov/geomag_cdaw/Data.html >>> > >>> > Thanks, >>> > Regards, >>> > Dave >>> > >>> > >>> > David F. Webb >>> > AFRL/VSBXS & ISR; Boston College >>> > 29 Randolph Road >>> > Hanscom AFB, MA 01731-3010 >>> > Tel.: 781-377-3086 Fax: 781-377-3160 >>> > E-mail: david.webb@hanscom.af.mil >>> > URL(updated 2003): http://www2.bc.edu/~webbd >>> > >> >>-- >>Ian Richardson >>Code 661, GSFC, Greenbelt, MD 20771 (Building 2, Rm 25) >>Tel: 301-286-3079; Fax: 301-286-1682; > > From jiez@scs.gmu.edu Fri Mar 4 11:17:58 2005 Return-Path: Received: from solar.scs.gmu.edu (solar.scs.gmu.edu [129.174.124.133]) (authenticated bits=0) by sv01.scs.gmu.edu (8.13.1/8.12.8) with ESMTP id j24GHugg008738 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Fri, 4 Mar 2005 11:17:58 -0500 Subject: RE: superstorms? From: Jie Zhang Reply-To: jiez@scs.gmu.edu To: Webb David F Contr AFRL/VSBX In-Reply-To: <010F73C38C145744BAE4599B97F020E302D5B2C9@ml66sc-mb-05.hanscom.af.mil> References: <010F73C38C145744BAE4599B97F020E302D5B2C9@ml66sc-mb-05.hanscom.af.mil> Organization: George Mason University Message-Id: <1109953044.14803.2.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.5 (1.4.5-9) Date: Fri, 04 Mar 2005 11:17:24 -0500 Content-Transfer-Encoding: 7bit Status: O X-UID: 25196 Content-Length: 8858 X-Keywords: Content-Type: text/plain; charset=us-ascii X-Evolution-Source: imap://jiez@mail.scs.gmu.edu/ X-Evolution: 0000001e-0110 You are right. I will make it, but only for the events we've extensively discussed like the one of 1999/10/22. -Jie On Fri, 2005-03-04 at 11:06, Webb David F Contr AFRL/VSBX wrote: > Jie, > It is worth doing after the workshop but its real usefulness will be if the emails are available to us AT the workshop. Otherwise people have to bring paper copies or reconstruct what they said. Perhaps I can find out how to copy those I have and bring them with me. > > Dave > > -----Original Message----- > From: Jie Zhang [mailto:jiez@scs.gmu.edu] > Sent: Friday, March 04, 2005 10:57 AM > To: Webb David F Contr AFRL/VSBX > Cc: 'Andrei Zhukov'; Nariaki Nitta; Ian Richardson; Alejandro Lara; > Alexander Nindos; Angelos Vourlidas; Barbara Thompson; Chin-Chun Wu; > Christophe Marque; Daniel Berdichevsky; Doug Biesecker; Cliver Edward W > Civ AFRL/VSBXS; Emilia Huttunen; Georgoulis Manolis; Hong Xie; John > Steinberg; Justin Kasper; Nat Gopalswamy; Robert MacDowall; Ryuho > Kataoka; Seiji Yashiro; Vasyl Yurchyshyn; Volker Bothmer; Yang Liu > Subject: RE: superstorms? > > > Dave, this is a good idea. This can be done for a few controversial > events. But I may have to do it after the workshop. -Jie > > On Fri, 2005-03-04 at 10:23, Webb David F Contr AFRL/VSBX wrote: > > Jie, and all, > > This discussion of event 22, Oct 1999, raises a problem with me. We need to somehow archive these emails relating to specific events on the website so we can retrieve them at the workshop. Perhaps you can save all the general WG1 emails in a single dir. If so, I suggest archiving all of them from several weeks ago to the present, and up to the start of the workshop. Also, this will be useful after the workshop for followup work on these events. > > > > What does everyone else think about this? > > > > Regards, > > Dave > > > > -----Original Message----- > > From: Andrei Zhukov [mailto:Andrei.Zhukov@oma.be] > > Sent: Friday, March 04, 2005 8:42 AM > > To: Nariaki Nitta; Ian Richardson > > Cc: Webb David F Contr AFRL/VSBX; 'jukozyra@engin.umich.edu'; Alejandro > > Lara; Alexander Nindos; Angelos Vourlidas; Barbara Thompson; Chin-Chun > > Wu; Christophe Marque; Daniel Berdichevsky; Doug Biesecker; Cliver > > Edward W Civ AFRL/VSBXS; Emilia Huttunen; Georgoulis Manolis; Hong Xie; > > Jie Zhang; John Steinberg; Justin Kasper; Nat Gopalswamy; Robert > > MacDowall; Ryuho Kataoka; Seiji Yashiro; Vasyl Yurchyshyn; Volker > > Bothmer; Yang Liu > > Subject: Re: superstorms? > > > > > > I have also checked the event 22 (October 22, 1999). > > > > Interplanetary signature: I agree with Ian that it's an ICME interacting with > > the fast flow from a coronal hole. Note that this ICME has signatures of an > > over-expanding ICME: enhanced density and magnetic field at the front and at > > the end, with a possible fast reverse shock right after 6:00 on Oct. 22. But > > this may be due to the compression of the ICME's rear part by the following > > fast stream. I'm not sure if it is a magnetic cloud, but if so, it should be > > of the NWS type. Following coronal hole has N polarity. > > > > Solar source: I fully agree with Nariaki. A partial halo CME (not reported in > > any catalogue) is first barely seen above the LASCO C2 occulter at 23:50 on > > Oct. 17, above the SSE limb. At the same time another CME (narrow, 87 deg > > width, PA 40 according to Gopal's catalogue) appears above the NE limb. > > However, these are TWO different CMEs as can be seen in running difference > > images around 6:50 Oct. 18. A relatively narrow bright CME is above the NE > > limb, and a weak partial halo spans the solar limb from ENE to SSW. Above the > > ENE limb it overlaps with quasi-radial structures of the narrow CME. > > > > At 23:11 EIT shows two simultaneous eruptions: at S28E11 and N05E37 > > (coordinates only to guide the eye, both regions are quite extended). Both > > have very clear dimmings (see running difference movie at > > ftp://omaftp.oma.be/pub/astro/andreiz/CDAW/EIT195_19991017-18.gif), the > > southern one has also a post-eruption arcade and the heated erupting filament > > matter. This unambiguously demonstrates the occurrence of a CME. The > > simultaneity of two eruptions (as far as we can determine with the limited > > EIT temporal cadence) makes me think that they represent signatures of one > > large-scale eruption which is visible as a partial halo CME by C2. SXT and > > EIT 284 data suggest that these two regions are magnetically connected. > > > > I don't think that these two eruption centers correspond to two CMEs seen by > > LASCO. LASCO shows the erupted matter predominantly above the NE limb and the > > partial halo is very weak. On the contrary, EIT data suggests that the most > > of the plasma was erupted from the southern source region. It seems that the > > narrow CME above the NE limb is a backside one - EIT shows no more eruptive > > signatures around this time. > > > > This event demonstrates that sometimes EIT can show more obvious CME > > signatures than LASCO. A space weather forecaster could miss such a weak > > partial halo CME, and such a severe storm may be unpredicted! Additionally, > > it suggests that it may be not correct to talk about a single localized CME > > source region. > > > > Andrei. > > > > > > On Friday 04 March 2005 06:31, Nariaki Nitta wrote: > > > Hello Ian, > > > > > > Thank you for the message, which clarified lots of things, together with > > > the informative plots of ACE data (with Dst). > > > > > > Indeed I see in SXT data > > > (http://www.lmsal.com/nitta/movies/sxt_almg_19991017_09/SXT_AlMg_19991017_0 > > >9.html) a global coronal restructuring between 17-Oct-1999 22 UT and > > > 18-Oct-1999 03 UT (between a long data gap). The EIT daily MPEG movie at > > > NRL > > > (http://lasco-www.nrl.navy.mil/daily_mpg/1999_10/991017_195.mpg) also > > > shows corresponding large-scale changes and an eruption from a southern > > > region at 23:11 (see also > > > http://www.lmsal.com/nitta/movies/eit_19971017_18/EIT195_19991017_18.html). > > > Note that these locations are far from the active region (AR 8731) > > > responsible for the 20-Oct-1999 filament eruption and the perhaps > > > associated slow CME. It is just west of the coronal hole that provided > > > the high speed stream as you wrote. Note that Jie's latest list > > > (http://cdaw.gsfc.nasa.gov/geomag_cdaw/data/cdaw1/Zhang_source/Data_Sun_Sou > > >rce_Zhang.html) mentions a CME at "1998/10/18 01:26 PA: 135; C2; C3 (not in > > > catalog)." I presume it is 1999/10/18. It would be beneficial if someone > > > produces a LASCO movie around this time. > > > > > > This particular event indicates the need for collaborations of experts > > > of various distances from the solar surface just to identify the origin > > > of some of the storms. > > > > > > Good night, > > > > > > Nariaki > > > > > > Ian Richardson wrote on 03.03.2005 20:35: > > > > Hi Nariaki, > > > > > > > > Oh yes, that event! My take is that this is a high-speed stream that is > > > > interacting with an ICME. The interface betweeh the two structures may > > > > be at ~6 UT on Oct 22, although ICME-like plasma composition (e.g., > > > > enhanced O7/O6, Fe charge states) does appear to persist to ~12 UT. The > > > > exceptionally strong storm presumably arises from the strong southward > > > > field in the structured) ICME, possibly enhanced by compression of the > > > > ICME magnetic field by the interaction with the high-speed stream. > > > > > > > > Anyone else have an opinion? > > > > > > > > The slow CME can probably be ruled out as the source of the ICME refered > > > > to above. The ICME has arrived at Earth by ~8 UT on October 21. This > > > > is only 26 hours after the CME, implying a high transit speed of ~1625 > > > > km/s. This seems incompatible with the slow (327 km/s) CME at the Sun > > > > and the modest (<~500 km/s) in-situ speed of the ICME. (Furthermore, the > > > > associated ICME-driven shock arrived even (~6 hours) earlier!) In > > > > addition, my impression is that the EIT activity associated with this > > > > CME was towards the west limb, (so the "E15" location is surprising) and > > > > that the CME rises above the west limb. I suspect that this CME was > > > > probably not directed towards the Earth. > > > > > > > > I would imagine that the true source of the ICME would be reasonably > > > > close to central meridian ~3-4 days prior to October 21, i.e. around > > > > October 17-18, perhaps in the same AR as that producing the October 20 > > > > CME. > > > > > > > > EIT 284 A observations do show a small near-equatorial coronal hole at ~ > > > > central meridian on October 21 that presumably could be the source of > > > > the high-speed stream. > > > > > > > > Regards, > > > > > > > > Ian From David.Webb@hanscom.af.mil Thu Mar 3 16:18:02 2005 Return-Path: Received: from FSMXRD01.hanscom.af.mil (thunderbird.hanscom.af.mil [129.53.219.254]) by sv01.scs.gmu.edu (8.13.1/8.12.8) with ESMTP id j23LI2kY020034 for ; Thu, 3 Mar 2005 16:18:02 -0500 Received: by fsmxrd01.hanscom.af.mil with Internet Mail Service (5.5.2657.72) id ; Thu, 3 Mar 2005 16:17:56 -0500 Message-ID: <010F73C38C145744BAE4599B97F020E302D5B2BC@ml66sc-mb-05.hanscom.af.mil> From: Webb David F Contr AFRL/VSBX To: "'jukozyra@engin.umich.edu'" Cc: Alejandro Lara , Alexander Nindos , Andrei Zhukov , Angelos Vourlidas , Barbara Thompson , Chin-Chun Wu , Christophe Marque , Daniel Berdichevsky , Dave Webb , Doug Biesecker , Ed Cliver , Emilia Huttunen , Georgoulis Manolis , Hong Xie , Ian Richardson , Jie Zhang , John Steinberg , Justin Kasper , Nariaki Nitta , Nat Gopalswamy , Robert MacDowall , Ryuho Kataoka , Seiji Yashiro , Vasyl Yurchyshyn , Volker Bothmer , Yang Liu Subject: RE: superstorms? Date: Thu, 3 Mar 2005 16:17:55 -0500 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2657.72) Content-Type: text/plain; charset="iso-8859-1" Status: RO X-UID: 25113 Content-Length: 2317 X-Status: A X-Keywords: X-Evolution-Source: imap://jiez@mail.scs.gmu.edu/ X-Evolution: 00000020-0011 Thanks Janet, this will be a big help. Maybe now we can make progress on the important solar-solar wind drivers of such storms. Let me know if and what specific parameters you or Mike are interested in. Jie, I suggest you label these particular storms in our list. They are numbers 22, 25, 27, 37, 38, 47, 68, 69, 70, 7-10 Nov. 2004 (yet to be added and a big reason to add it!). Apparently there are none before No. 22 in our list that qualify. Regards, Dave -----Original Message----- From: jukozyra@engin.umich.edu [mailto:jukozyra@engin.umich.edu] Sent: Thursday, March 03, 2005 4:03 PM To: Webb David F Contr AFRL/VSBX Subject: Re: superstorms? Hi Dave, I won't be at the CDAW, Mike Liemohn is representing our group there. The question of "what is a superstorm?" is a good one. We are looking at this more carefully now for a presentation in Toulouse this summer. However, in the past I have been using Dst<-240 nT from Mac-Mahon et al., JGR 102, 14199, 1997. Another paper, which Susan Gussenhoven participated in, uses 4 different magnetic indices (ap, Kp, AE and Dst) to pick out the top 2% of severe magnetic storms [Bell et al.,JGR, 14189, 1997]. My list of superstorms since 1999 based on Dst* (ring current strength) includes: 22-23 Oct 1999 6-7 April 2000 15-16 July 2000 31 March - 1 April 2001 (double-peaked) 11-12 April 2001 6-7 Nov 2001 29-31 Oct 2003 (double-peaked) 20-21 Nov 2003 7-10 Nov 2004 (double-peaked) If I can be of any other help, let me know. Regards, Janet This is actually from a paper by Quoting Webb David F Contr AFRL/VSBX : > Janet, > I don't know if you are going to the Storm CDAW in 2 weeks, but we are > studying the 77 storms with Dst < -100 nT. We have discussed analyzing the > solar inputs for superstorms and this is a good opportunity. Can you provide > me with a dsfinition of a superstorm, eg, is it just the Dst level or > sonething more, and a sublist of superstorms from the CDAW list ?: > http://cdaw.gsfc.nasa.gov/geomag_cdaw/Data.html > > Thanks, > Regards, > Dave > > > David F. Webb > AFRL/VSBXS & ISR; Boston College > 29 Randolph Road > Hanscom AFB, MA 01731-3010 > Tel.: 781-377-3086 Fax: 781-377-3160 > E-mail: david.webb@hanscom.af.mil > URL(updated 2003): http://www2.bc.edu/~webbd > From jiez@scs.gmu.edu Fri Mar 4 10:31:09 2005 Return-Path: Received: from solar.scs.gmu.edu (solar.scs.gmu.edu [129.174.124.133]) (authenticated bits=0) by sv01.scs.gmu.edu (8.13.1/8.12.8) with ESMTP id j24FV9IG008323 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO); Fri, 4 Mar 2005 10:31:09 -0500 Subject: Re: superstorms? From: Jie Zhang Reply-To: jiez@scs.gmu.edu To: Nariaki Nitta Cc: Ian Richardson , Webb David F Contr AFRL/VSBX , "'jukozyra@engin.umich.edu'" , Alejandro Lara , Alexander Nindos , Andrei Zhukov , Angelos Vourlidas , Barbara Thompson , Chin-Chun Wu , Christophe Marque , Daniel Berdichevsky , Doug Biesecker , Ed Cliver , Emilia Huttunen , Georgoulis Manolis , Hong Xie , John Steinberg , Justin Kasper , Nat Gopalswamy , Robert MacDowall , Ryuho Kataoka , Seiji Yashiro , Vasyl Yurchyshyn , Volker Bothmer , Yang Liu In-Reply-To: <422800B0.4020503@lmsal.com> References: <010F73C38C145744BAE4599B97F020E302D5B2BC@ml66sc-mb-05.hanscom.af.mil> <6.1.2.0.0.20050303175210.01b46008@lheapop.gsfc.nasa.gov> <4227AB39.4020702@lmsal.com> <6.1.2.0.1.20050303223812.01da2d80@lheapop.gsfc.nasa.gov> <422800B0.4020503@lmsal.com> Organization: George Mason University Message-Id: <1109950236.14613.12.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Ximian Evolution 1.4.5 (1.4.5-9) Date: Fri, 04 Mar 2005 10:30:37 -0500 Content-Transfer-Encoding: 7bit Status: O X-UID: 25186 Content-Length: 8473 X-Keywords: Content-Type: text/plain; charset=us-ascii X-Evolution-Source: imap://jiez@mail.scs.gmu.edu/ X-Evolution: 00000022-0010 Nariaki, Thanks for your careful double check. I also thought this is a case of a combination of CIR and CME; there are other cased like this in my list. For this event, a coronal hole is close to the disk center, e.g., at N11E15 at 10/20 16:36 UT ( http://cdaw.gsfc.nasa.gov/geomag_cdaw/data/cdaw1/Zhang_source/19991022/19991020_1636_eit_195.png ). A weak partial halo CME occurred at 1999/10/18 01:26 (PA ~ 135), which escaped the "standard" detection pipeline. It is hard to see it unless you look at the "right-scaled" movie very carefully. But it may have surface source region, that are two almost simultaneous dimming, e.g., S33E10 and S04E37 at 10/17 23:24 UT (http://cdaw.gsfc.nasa.gov/geomag_cdaw/data/cdaw1/Zhang_source/19991022/19991017_2324_eit_195_rd.png ). The occurrence of a Geo-effective CME with no or little surface signature is not rare, especially when it is associated with a coronal hole, or CIR in IP space. I would like to see the global coronal magnetic field for these events. Regards, -Jie On Fri, 2005-03-04 at 01:31, Nariaki Nitta wrote: > Hello Ian, > > Thank you for the message, which clarified lots of things, together with > the informative plots of ACE data (with Dst). > > Indeed I see in SXT data > (http://www.lmsal.com/nitta/movies/sxt_almg_19991017_09/SXT_AlMg_19991017_09.html) > a global coronal restructuring between 17-Oct-1999 22 UT and 18-Oct-1999 > 03 UT (between a long data gap). The EIT daily MPEG movie at NRL > (http://lasco-www.nrl.navy.mil/daily_mpg/1999_10/991017_195.mpg) also > shows corresponding large-scale changes and an eruption from a southern > region at 23:11 (see also > http://www.lmsal.com/nitta/movies/eit_19971017_18/EIT195_19991017_18.html). > Note that these locations are far from the active region (AR 8731) > responsible for the 20-Oct-1999 filament eruption and the perhaps > associated slow CME. It is just west of the coronal hole that provided > the high speed stream as you wrote. Note that Jie's latest list > (http://cdaw.gsfc.nasa.gov/geomag_cdaw/data/cdaw1/Zhang_source/Data_Sun_Source_Zhang.html) > mentions a CME at "1998/10/18 01:26 PA: 135; C2; C3 (not in catalog)." > I presume it is 1999/10/18. It would be beneficial if someone produces > a LASCO movie around this time. > > This particular event indicates the need for collaborations of experts > of various distances from the solar surface just to identify the origin > of some of the storms. > > Good night, > > Nariaki > > > > > > Ian Richardson wrote on 03.03.2005 20:35: > > > Hi Nariaki, > > > > Oh yes, that event! My take is that this is a high-speed stream that is > > interacting with an ICME. The interface betweeh the two structures may > > be at ~6 UT on Oct 22, although ICME-like plasma composition (e.g., > > enhanced O7/O6, Fe charge states) does appear to persist to ~12 UT. The > > exceptionally strong storm presumably arises from the strong southward > > field in the structured) ICME, possibly enhanced by compression of the > > ICME magnetic field by the interaction with the high-speed stream. > > > > Anyone else have an opinion? > > > > The slow CME can probably be ruled out as the source of the ICME refered > > to above. The ICME has arrived at Earth by ~8 UT on October 21. This > > is only 26 hours after the CME, implying a high transit speed of ~1625 > > km/s. This seems incompatible with the slow (327 km/s) CME at the Sun > > and the modest (<~500 km/s) in-situ speed of the ICME. (Furthermore, the > > associated ICME-driven shock arrived even (~6 hours) earlier!) In > > addition, my impression is that the EIT activity associated with this > > CME was towards the west limb, (so the "E15" location is surprising) and > > that the CME rises above the west limb. I suspect that this CME was > > probably not directed towards the Earth. > > > > I would imagine that the true source of the ICME would be reasonably > > close to central meridian ~3-4 days prior to October 21, i.e. around > > October 17-18, perhaps in the same AR as that producing the October 20 CME. > > > > EIT 284 A observations do show a small near-equatorial coronal hole at ~ > > central meridian on October 21 that presumably could be the source of > > the high-speed stream. > > > > Regards, > > > > Ian > > > > > > > > At 07:26 PM 3/3/2005, Nariaki Nitta wrote: > > > >> And No. 22 is a difficult case, isn't it? Jie's list shows a CIR (can > >> it be the source of a superstorm?), and Nat's list shows a slow CME > >> (20-Oct-1999 06 UT) perhaps associated with a minor filament eruption. > >> TRACE data (e.g., > >> http://www.lmsal.com/nitta/movies/19991020_05/trace195/TRACE195_991020_05.html) > >> indicate a reluctant filament eruption.... > >> > >> Regards > >> Nariaki > >> > >> > >> > >> Ian Richardson wrote on 03.03.2005 15:00: > >> > >>> No events before no. 22 - presumably consistent with the the > >>> previously reported tendency for particularly energetic events (SEPs, > >>> GLEs, Forbush decreases, fast CMEs/ICMEs, etc) generally to occur > >>> more frequently following, rather than before, solar maximum. > >>> > >>> At 04:17 PM 3/3/2005, Webb David F Contr AFRL/VSBX wrote: > >>> > >>>> Jie, > >>>> I suggest you label these particular storms in our list. They are > >>>> numbers 22, 25, 27, 37, 38, 47, 68, 69, 70, 7-10 Nov. 2004 (yet to > >>>> be added and a big reason to add it!). Apparently there are none > >>>> before No. 22 in our list that qualify. > >>>> > >>>> Regards, > >>>> Dave > >>>> > >>>> -----Original Message----- > >>>> From: jukozyra@engin.umich.edu [mailto:jukozyra@engin.umich.edu] > >>>> Sent: Thursday, March 03, 2005 4:03 PM > >>>> To: Webb David F Contr AFRL/VSBX > >>>> Subject: Re: superstorms? > >>>> > >>>> > >>>> Hi Dave, > >>>> > >>>> I won't be at the CDAW, Mike Liemohn is representing our group there. > >>>> > >>>> The question of "what is a superstorm?" is a good one. We are > >>>> looking at this > >>>> more carefully now for a presentation in Toulouse this summer. > >>>> However, in the > >>>> past I have been using Dst<-240 nT from Mac-Mahon et al., JGR 102, > >>>> 14199, 1997. > >>>> Another paper, which Susan Gussenhoven participated in, uses 4 > >>>> different > >>>> magnetic indices (ap, Kp, AE and Dst) to pick out the top 2% of severe > >>>> magnetic storms [Bell et al.,JGR, 14189, 1997]. > >>>> > >>>> My list of superstorms since 1999 based on Dst* (ring current strength) > >>>> includes: > >>>> > >>>> 22-23 Oct 1999 > >>>> 6-7 April 2000 > >>>> 15-16 July 2000 > >>>> 31 March - 1 April 2001 (double-peaked) > >>>> 11-12 April 2001 > >>>> 6-7 Nov 2001 > >>>> 29-31 Oct 2003 (double-peaked) > >>>> 20-21 Nov 2003 > >>>> 7-10 Nov 2004 (double-peaked) > >>>> > >>>> If I can be of any other help, let me know. > >>>> > >>>> Regards, > >>>> Janet > >>>> > >>>> > >>>> > >>>> > >>>> This is actually from a paper by > >>>> > >>>> Quoting Webb David F Contr AFRL/VSBX : > >>>> > >>>> > Janet, > >>>> > I don't know if you are going to the Storm CDAW in 2 weeks, but we > >>>> are > >>>> > studying the 77 storms with Dst < -100 nT. We have discussed > >>>> analyzing the > >>>> > solar inputs for superstorms and this is a good opportunity. Can > >>>> you provide > >>>> > me with a dsfinition of a superstorm, eg, is it just the Dst level or > >>>> > sonething more, and a sublist of superstorms from the CDAW list ?: > >>>> > http://cdaw.gsfc.nasa.gov/geomag_cdaw/Data.html > >>>> > > >>>> > Thanks, > >>>> > Regards, > >>>> > Dave > >>>> > > >>>> > > >>>> > David F. Webb > >>>> > AFRL/VSBXS & ISR; Boston College > >>>> > 29 Randolph Road > >>>> > Hanscom AFB, MA 01731-3010 > >>>> > Tel.: 781-377-3086 Fax: 781-377-3160 > >>>> > E-mail: david.webb@hanscom.af.mil > >>>> > URL(updated 2003): http://www2.bc.edu/~webbd > >>>> > > >>> > >>> > >>> -- > >>> Ian Richardson > >>> Code 661, GSFC, Greenbelt, MD 20771 (Building 2, Rm 25) > >>> Tel: 301-286-3079; Fax: 301-286-1682; > >> > >> > >> > > > > > > -- --------------------------------------------------------------------- Dr. Jie Zhang George Mason University School of Computational Sciences 4400 University Dr., Fairfax, VA 22030, USA Office Phone: (703)993-1998 Fax: (703)993-1980 E-mail: jiez@scs.gmu.edu URL: http://solar.scs.gmu.edu ---------------------------------------------------------------------- From David.Webb@hanscom.af.mil Fri Mar 4 11:31:34 2005 Return-Path: Received: from FSMXRD01.hanscom.af.mil (thunderbird.hanscom.af.mil [129.53.219.254]) by sv01.scs.gmu.edu (8.13.1/8.12.8) with ESMTP id j24GVYBJ008852 for ; Fri, 4 Mar 2005 11:31:34 -0500 Received: by fsmxrd01.hanscom.af.mil with Internet Mail Service (5.5.2657.72) id ; Fri, 4 Mar 2005 11:31:29 -0500 Message-ID: <010F73C38C145744BAE4599B97F020E302D5B2CB@ml66sc-mb-05.hanscom.af.mil> From: Webb David F Contr AFRL/VSBX To: "'jiez@scs.gmu.edu'" Subject: RE: superstorms? Date: Fri, 4 Mar 2005 11:31:28 -0500 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2657.72) Status: O X-UID: 25201 Content-Length: 9044 X-Keywords: Content-Type: text/plain; charset=iso-8859-1 X-Evolution-Source: imap://jiez@mail.scs.gmu.edu/ X-Evolution: 00000024-0110 OK, thanks. Dave -----Original Message----- From: Jie Zhang [mailto:jiez@scs.gmu.edu] Sent: Friday, March 04, 2005 11:17 AM To: Webb David F Contr AFRL/VSBX Subject: RE: superstorms? You are right. I will make it, but only for the events we've extensively discussed like the one of 1999/10/22. -Jie On Fri, 2005-03-04 at 11:06, Webb David F Contr AFRL/VSBX wrote: > Jie, > It is worth doing after the workshop but its real usefulness will be if the emails are available to us AT the workshop. Otherwise people have to bring paper copies or reconstruct what they said. Perhaps I can find out how to copy those I have and bring them with me. > > Dave > > -----Original Message----- > From: Jie Zhang [mailto:jiez@scs.gmu.edu] > Sent: Friday, March 04, 2005 10:57 AM > To: Webb David F Contr AFRL/VSBX > Cc: 'Andrei Zhukov'; Nariaki Nitta; Ian Richardson; Alejandro Lara; > Alexander Nindos; Angelos Vourlidas; Barbara Thompson; Chin-Chun Wu; > Christophe Marque; Daniel Berdichevsky; Doug Biesecker; Cliver Edward W > Civ AFRL/VSBXS; Emilia Huttunen; Georgoulis Manolis; Hong Xie; John > Steinberg; Justin Kasper; Nat Gopalswamy; Robert MacDowall; Ryuho > Kataoka; Seiji Yashiro; Vasyl Yurchyshyn; Volker Bothmer; Yang Liu > Subject: RE: superstorms? > > > Dave, this is a good idea. This can be done for a few controversial > events. But I may have to do it after the workshop. -Jie > > On Fri, 2005-03-04 at 10:23, Webb David F Contr AFRL/VSBX wrote: > > Jie, and all, > > This discussion of event 22, Oct 1999, raises a problem with me. We need to somehow archive these emails relating to specific events on the website so we can retrieve them at the workshop. Perhaps you can save all the general WG1 emails in a single dir. If so, I suggest archiving all of them from several weeks ago to the present, and up to the start of the workshop. Also, this will be useful after the workshop for followup work on these events. > > > > What does everyone else think about this? > > > > Regards, > > Dave > > > > -----Original Message----- > > From: Andrei Zhukov [mailto:Andrei.Zhukov@oma.be] > > Sent: Friday, March 04, 2005 8:42 AM > > To: Nariaki Nitta; Ian Richardson > > Cc: Webb David F Contr AFRL/VSBX; 'jukozyra@engin.umich.edu'; Alejandro > > Lara; Alexander Nindos; Angelos Vourlidas; Barbara Thompson; Chin-Chun > > Wu; Christophe Marque; Daniel Berdichevsky; Doug Biesecker; Cliver > > Edward W Civ AFRL/VSBXS; Emilia Huttunen; Georgoulis Manolis; Hong Xie; > > Jie Zhang; John Steinberg; Justin Kasper; Nat Gopalswamy; Robert > > MacDowall; Ryuho Kataoka; Seiji Yashiro; Vasyl Yurchyshyn; Volker > > Bothmer; Yang Liu > > Subject: Re: superstorms? > > > > > > I have also checked the event 22 (October 22, 1999). > > > > Interplanetary signature: I agree with Ian that it's an ICME interacting with > > the fast flow from a coronal hole. Note that this ICME has signatures of an > > over-expanding ICME: enhanced density and magnetic field at the front and at > > the end, with a possible fast reverse shock right after 6:00 on Oct. 22. But > > this may be due to the compression of the ICME's rear part by the following > > fast stream. I'm not sure if it is a magnetic cloud, but if so, it should be > > of the NWS type. Following coronal hole has N polarity. > > > > Solar source: I fully agree with Nariaki. A partial halo CME (not reported in > > any catalogue) is first barely seen above the LASCO C2 occulter at 23:50 on > > Oct. 17, above the SSE limb. At the same time another CME (narrow, 87 deg > > width, PA 40 according to Gopal's catalogue) appears above the NE limb. > > However, these are TWO different CMEs as can be seen in running difference > > images around 6:50 Oct. 18. A relatively narrow bright CME is above the NE > > limb, and a weak partial halo spans the solar limb from ENE to SSW. Above the > > ENE limb it overlaps with quasi-radial structures of the narrow CME. > > > > At 23:11 EIT shows two simultaneous eruptions: at S28E11 and N05E37 > > (coordinates only to guide the eye, both regions are quite extended). Both > > have very clear dimmings (see running difference movie at > > ftp://omaftp.oma.be/pub/astro/andreiz/CDAW/EIT195_19991017-18.gif), the > > southern one has also a post-eruption arcade and the heated erupting filament > > matter. This unambiguously demonstrates the occurrence of a CME. The > > simultaneity of two eruptions (as far as we can determine with the limited > > EIT temporal cadence) makes me think that they represent signatures of one > > large-scale eruption which is visible as a partial halo CME by C2. SXT and > > EIT 284 data suggest that these two regions are magnetically connected. > > > > I don't think that these two eruption centers correspond to two CMEs seen by > > LASCO. LASCO shows the erupted matter predominantly above the NE limb and the > > partial halo is very weak. On the contrary, EIT data suggests that the most > > of the plasma was erupted from the southern source region. It seems that the > > narrow CME above the NE limb is a backside one - EIT shows no more eruptive > > signatures around this time. > > > > This event demonstrates that sometimes EIT can show more obvious CME > > signatures than LASCO. A space weather forecaster could miss such a weak > > partial halo CME, and such a severe storm may be unpredicted! Additionally, > > it suggests that it may be not correct to talk about a single localized CME > > source region. > > > > Andrei. > > > > > > On Friday 04 March 2005 06:31, Nariaki Nitta wrote: > > > Hello Ian, > > > > > > Thank you for the message, which clarified lots of things, together with > > > the informative plots of ACE data (with Dst). > > > > > > Indeed I see in SXT data > > > (http://www.lmsal.com/nitta/movies/sxt_almg_19991017_09/SXT_AlMg_19991017_0 > > >9.html) a global coronal restructuring between 17-Oct-1999 22 UT and > > > 18-Oct-1999 03 UT (between a long data gap). The EIT daily MPEG movie at > > > NRL > > > (http://lasco-www.nrl.navy.mil/daily_mpg/1999_10/991017_195.mpg) also > > > shows corresponding large-scale changes and an eruption from a southern > > > region at 23:11 (see also > > > http://www.lmsal.com/nitta/movies/eit_19971017_18/EIT195_19991017_18.html). > > > Note that these locations are far from the active region (AR 8731) > > > responsible for the 20-Oct-1999 filament eruption and the perhaps > > > associated slow CME. It is just west of the coronal hole that provided > > > the high speed stream as you wrote. Note that Jie's latest list > > > (http://cdaw.gsfc.nasa.gov/geomag_cdaw/data/cdaw1/Zhang_source/Data_Sun_Sou > > >rce_Zhang.html) mentions a CME at "1998/10/18 01:26 PA: 135; C2; C3 (not in > > > catalog)." I presume it is 1999/10/18. It would be beneficial if someone > > > produces a LASCO movie around this time. > > > > > > This particular event indicates the need for collaborations of experts > > > of various distances from the solar surface just to identify the origin > > > of some of the storms. > > > > > > Good night, > > > > > > Nariaki > > > > > > Ian Richardson wrote on 03.03.2005 20:35: > > > > Hi Nariaki, > > > > > > > > Oh yes, that event! My take is that this is a high-speed stream that is > > > > interacting with an ICME. The interface betweeh the two structures may > > > > be at ~6 UT on Oct 22, although ICME-like plasma composition (e.g., > > > > enhanced O7/O6, Fe charge states) does appear to persist to ~12 UT. The > > > > exceptionally strong storm presumably arises from the strong southward > > > > field in the structured) ICME, possibly enhanced by compression of the > > > > ICME magnetic field by the interaction with the high-speed stream. > > > > > > > > Anyone else have an opinion? > > > > > > > > The slow CME can probably be ruled out as the source of the ICME refered > > > > to above. The ICME has arrived at Earth by ~8 UT on October 21. This > > > > is only 26 hours after the CME, implying a high transit speed of ~1625 > > > > km/s. This seems incompatible with the slow (327 km/s) CME at the Sun > > > > and the modest (<~500 km/s) in-situ speed of the ICME. (Furthermore, the > > > > associated ICME-driven shock arrived even (~6 hours) earlier!) In > > > > addition, my impression is that the EIT activity associated with this > > > > CME was towards the west limb, (so the "E15" location is surprising) and > > > > that the CME rises above the west limb. I suspect that this CME was > > > > probably not directed towards the Earth. > > > > > > > > I would imagine that the true source of the ICME would be reasonably > > > > close to central meridian ~3-4 days prior to October 21, i.e. around > > > > October 17-18, perhaps in the same AR as that producing the October 20 > > > > CME. > > > > > > > > EIT 284 A observations do show a small near-equatorial coronal hole at ~ > > > > central meridian on October 21 that presumably could be the source of > > > > the high-speed stream. > > > > > > > > Regards, > > > > > > > > Ian