LF: Re: Poor conditions

["Alan Melia" <alan.melia@btinternet.com>]

Hi Laurence and Roelof, Yes that was a big one on the 17th. I dont remember the Dst being depressed to -230nT for some quite long time. My thumbnail estimate says that it could take at least 14 days and possibly up to 21 days to really get back to to good conditions again. The succession of shocks really loaded up the ring current, and although the Dst has risen to -35nT its rate of increase has flattened out.

Because the CME "snow-ploughed" it way though a coronal hole high speed stream the event produced a large multiple proton event which has died away now, but the PCA effects tend to linger. We are still gettting shocks (Kp 6 yesterday and Kp=5 today) which may be "sub-storms". These occur when ions and electrons trapped in the mageto-tail are "spat back" towards Earth (another glob of plasma is spat in the opposite direction to conserve momentum) The mechanism is much like he release of energy from the strained Solar magnetic field that produced the CME. The trapped hot electrons "wind up" the field in the magneto-tail until it "snaps" into a lower energy state. The lost energy is carried by the ejected particles.

 

Alan

G3NYK 

 

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

From: Laurence KL7 L

To: rsgb_lf_group@blacksheep.org

Sent: Monday, March 23, 2015 3:57 PM

Subject: LF: Poor conditions

Since the 17th at 0650Z  and the start of the latest solar wind/geo effective uptick there have been no skywave WSPR2 475kHz decodes here in Alaska - this is the longest run of "nil points" Ive seen for a long time. That's nearly a week -
 
However  down on 136kHz, and keep my "is my rx working" sanity JA1CGM continues to blast away as "CGM"  most nights on QRSS60, sometime faster, around 136.1725 - 0930-1100Z on the better days making the 5000Kms or so path
 
 Signals have gradually deteriorated as we continue to top up the attenuative tank; 17, 18 and 19th were readable, but Im only getting partial IDs since then -
 
At times  I can still see DCF39 weakly on the bottom screen of   http://kl7l.com/LF00000.jpg 
 
HF isn't much better. At least we have a lot more light now to play in-
 
73
Laurence KL7 L  WE2 XPQ  WH2XBA/5
BP51IP Palmer Wasilla Alaska