Return-Path: Received: (qmail 3207 invoked from network); 14 May 2001 19:22:32 -0000 Received: from unknown (HELO warrior-inbound.servers.plus.net) (212.159.14.227) by excalibur-qfe1-smtp-plusnet.harl.plus.net with SMTP; 14 May 2001 19:22:32 -0000 Received: (qmail 22685 invoked from network); 14 May 2001 19:22:03 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by warrior with SMTP; 14 May 2001 19:22:03 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.16 #2) id 14zNoo-0006jp-00 for rsgb_lf_group-outgoing@blacksheep.org; Mon, 14 May 2001 20:15:46 +0100 Received: from gadolinium.btinternet.com ([194.73.73.111]) by post.thorcom.com with esmtp (Exim 3.16 #2) id 14zNok-0006jk-00 for rsgb_lf_group@blacksheep.org; Mon, 14 May 2001 20:15:42 +0100 Received: from [62.7.37.50] (helo=default) by gadolinium.btinternet.com with smtp (Exim 3.03 #83) id 14zNoD-00069H-00 for rsgb_lf_group@blacksheep.org; Mon, 14 May 2001 20:15:09 +0100 Message-ID: <003001c0dca9$a63eef60$456e01d5@default> From: "Alan Melia" To: "LF-Group" Subject: LF: re re T/A tests and Solar events Date: Mon, 14 May 2001 20:06:30 +0100 MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 4.72.3110.5 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: Hi Laurie, All the parameters of the solar distubances are at least weakly related so you will get some correlation with Sun-spot number of any other parameter. When the sun spot number is high there is a higher likelyhood of geomagnetic disturbances. When the sunspot number is low there is less likely to be Flares and the associtaed CMEs, although I believe there may still be Coronal hole events. What you may like to try is a correlation to failure (i.e. a negative correlation in statistical terms) with the Kp index, but delay it by one day. My rationale behind that it that when the Kp is high (5 or above) there are energetic ions injected into the atmosphere at the magnetic poles. These create the Aurora but also drift down into the lower layers and spread out into the D-layer (I believe). This latter effect seems to take about 24hours. The Index drops rapidly but the injected ions in the ionosphere decay only slowly and the events can last for anything from 3 to 14 days. The best archive I have of Kp is that published every month on the dxlc web site. If you have the NOAA SEC data the graphs and timings of the increases are given in 3 hourly avaerages. The thing is that the increase in Kp indicates that the plasma 'glob' of a CME or coronal hole event has made impact on the ionosphere, with the possibility of injecting energetic charges into the layer. The problem is that there is so much going on at present and so many events running in to each other that it is difficult to sort out cause and effect. I would be interested in the dates you have as I have collected 75 graphs of SXV now and I am having trouble relating them to propagation conditions. The dates you were active and the dates you were heard (times if possible) would be interesting. I am getting some ideas on how to model these events and maybe draw some conclusions, but it is probably quite contentious. (Watch this space) If anyone would like the SXV graph archive please ask. I have not lodged these with Rik as I did not know how to explain the relevance of the plots on the propagation over the North Atlantic. The SXV plots do show that the effects we have seen over the N.Atlantic are also in action on shorter paths. Cheers de Alan G3NYK Alan.Melia@btinternet.com