Topband: W7 Propagation 3/29/2021

[donovanf at erols.com]

Hi Luke, 


March and April (and September and October) are the months when 
the interplanetary magnetic field (IMF) is twice as likely to be 
oriented southwards (-Bz) than in June, July, December and January. 


S outhward IMF orientation is far more significant than the intensity 
of coronal hole high speed streams (CH HSS). CH HSS energy in 
the solar wind very efficiently transfers into the earth's magnetosphere 
and ionosphere when the IMF is oriented southwards for at least a 
few hours. T he earth's magnetosphere does an excellent job repelling 
almost all CH HSS energy w hen the IMF is oriented n orthwards (+ Bz) 
or neutral (-Bz less than 5 nT). 



Disturbed propagation will be much more extreme and much longer 
lasting when coronal mass ejections (CMEs) occur more frequently, 
likely starting next year. During the years near solar minimum the 
southward orientation of the IMF only infrequently lasts for more than 
two or three hours but when CMEs become more frequent the IMF 
sometimes persists in a southward orientation for days! ugh... 


By next year you'll be longing for the good old days of just a few 
hours of disturbed propagation caused by southward IMF concurrent 
with CH HSS. 


73 
Frank 
W3LPL 




----- Original Message -----

From: "List Mail" <mail10 at barefoothorse.com.au> 
To: "Bob Kile" <midnight18 at cox.net>, "Topband" <topband at contesting.com> 
Sent: Tuesday, March 30, 2021 11:22:05 PM 
Subject: Re: Topband: W7 Propagation 3/29/2021 

These Coronal Hole high speed solar winds seem to be quite relentless! I get the impression that I’m more affected by the disturbances than those North of me. I’m at 37 degrees South. 
I’ve been on some mornings, looking for Europe CW contacts. There seems to be a bare handful of ops on. I worked my first EA6 yesterday morning. Josep was using only 100 watts! In our evenings, there are a bare handful of CW ops on in NA too. Conditions that way have been very poor, when usually, the Equinox gives us good openings. 
As ever, we live in hope! There is no “Top Band Season” as far as I’m concerned. I’m on every day. 
73, Luke VK3HJ 

Sent from Mail for Windows 10 

From: Bob Kile 
Sent: Wednesday, 31 March 2021 3:35 AM 
To: Topband 
Subject: Topband: W7 Propagation 3/29/2021 

Out of the blue with continuous solar disruptions and high A and K 
indexes an opening occurred last evening. A Index zero and K index less 
than 1 the band was a bit noisy, typical of Spring time levels. Miracles 
do happen. 

I worked SM5EDX and SM3EVR from AZ QTH before I discovered my power 
level was only 25W! OK1CF made it into the log as well. Heard but not 
worked G3PQA, G3YRO and DL8LAS. Then the bell struck. At 04:00 UTC I 
lost remote Internet connection for the rest of the evening. :( 

160m the magic band.... 

Bob W7RH 

-- 
W7RH DM35OJ 

“Small is the number of people who see with their eyes and think with their minds.” – Albert Einstein 

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