[SFDXA] ARLP029 Propagation de K7RA

[William Marx]

> SB PROP @ ARL $ARLP029
> ARLP029 Propagation de K7RA
> 
> ZCZC AP29
> QST de W1AW  
> Propagation Forecast Bulletin 29  ARLP029
> From Tad Cook, K7RA
> Seattle, WA  July 15, 2016
> To all radio amateurs 
> 
> SB PROP ARL ARLP029
> ARLP029 Propagation de K7RA
> 
> As this solar cycle declines, we will occasionally see periods such
> as the past week when activity perks up and it seems that happy days
> are back.  Enjoy them when you can, while they last.  Any recovery
> is unpredictable and temporary.
> 
> Over the past reporting week (July 7 to 13) average daily sunspot
> number was 52.6, up 47.7 points from 4.9 in the previous week.  The
> previous week's activity was dominated by 5 out of the 7 days with
> zero sunspots.
> 
> Over the same periods, average daily solar flux rose from 73.1 to
> 91.6, a healthy advance.
> 
> Geomagnetic indices were also active, with planetary A index
> advancing 9 points to 15.7 from 6.7 and mid-latitude A index rising
> from 8.3 to 14.1 over the same two weeks.
> 
> Predicted solar flux is 94 on July 15, 91 on July 16 to 18, 86 on
> July 19, 82 on July 20 and 21, then 80, 77, 75, 73, 74, 73 and 72 on
> July 22 to 28, then 71, 72, 74, 72 and 77 on July 29 through August
> 2, then 83, 87, 92, 94 and 92 on August 3 to 7, 90 on August 8 to
> 13, 85 on August 14, 78 on August 15 and 16, 76 on August 17, and 77
> on August 18 and 19.
> 
> Predicted planetary A index is 14, 8 and 5 on July 15 to 17, 8 on
> July 18 and 19, 5 on July 20 and 21, then 7, 11, 10 and 6 on July 22
> to 25, then 4, 6, 7, 9, 8 and 7 on July 26 to 31, and 4 and 5 on
> August 1 and 2, 23 on August 3 and 4, then 14, 10, 20, 12, 8, 15 and
> 10 on August 5 to 11, 5 on August 12 and 13, then 4 and 14 on August
> 14 and 15 and 12 on August 16 and 17.
> 
> Geomagnetic activity forecast for the period July 15 to August 10,
> 2016 from Petr Kolman, OK1MGW.  Geomagnetic field will be:
> 
> Quiet on July 16-17, August 1-2 
> Mostly quiet on July 15, 24-26, 31, August 10 
> Quiet to unsettled on July 18, 21-23, 30, August 5-7, 9
> Quiet to active on July 19-20, 27-29, August 3-4, 8 
> Active to disturbed on August (3-4)
> 
> Increased solar wind from coronal holes is expected on July 19-21,
> 27-29, August 2-4, 7-8.
> 
> Parenthesis means lower probability of activity enhancement.
> 
> Bill Loftus, WA2VQF of Denville, New Jersey (and several others)
> sent this article, commenting "Good thing I only need 30 more on 80
> meters for 5BDXCC."
> 
> http://bit.ly/29CSDYs
> 
> Here is a nice resource from Australia's Space Weather Services,
> which displays in nice detail solar activity over all of the
> historic cycles, starting in 1754.
> 
> http://www.sws.bom.gov.au/Educational/2/3/1
> 
> You might miss this image, which shows all 24 cycles:
> 
> http://bit.ly/29zX76E
> 
> Back on April 13, 2016, Ray Bass, W7YKN of Sparks, Nevada (he uses
> the phonetics You Know Nothing!) wrote:
> 
> "I have a question that so far no one knows the answer to, including
> some astronomers and professors.
> 
> The numbers for the sunspot groups, like 2230, 2231, 2232 and so
> forth are in numerical order but where did they start?
> 
> Is there a 0001?  Did they start, at the beginning of a new 11 year
> cycle, or when they first started counting sun spots, etc., or did
> they start with a higher number than 0001?
> 
> So if I started at number 2230 and went backwards to the beginning
> where would I be (other than lost)?
> 
> We had discussions about this a few times on the air in rag chew
> sessions and all were interested but no one knew the answer."
> 
> I told Ray that at some time in the past I knew the answer, but have
> forgotten.
> 
> I forgot about it, then last week Ray wrote to me again, asking if I
> had learned anything about this.
> 
> It turns out the renumbering begins after sunspot group 9999, and it
> starts over at 0.  Note that he was not asking about the sunspot
> number, but the numbering of sunspots.  Sunspot number is an
> indicator of solar activity, but the numbering of sunspots is just a
> method of identifying individual sunspot groups, and it goes from 0
> to 9999.  After 10,000 sunspots, the numbers begin all over again.
> 
> The last time it did this was June 16, 2002.
> 
> Go to Spaceweather.com, and put June 15, 2002 in the archive
> (Spaceweather Time Machine), and you will see sunspots numbered up
> to 9998.  The next day they start over at 0 and there is also an
> explanation.
> 
> Compare the numbers on the sun on these two consecutive days, 14
> years ago:
> 
> http://spaceweather.com/archive.php?view=1&day=15&month=06&year=2002
> 
> http://spaceweather.com/archive.php?view=1&day=16&month=06&year=2002
> 
> I solved this by using the Spaceweather archive (Time Machine) and
> kept dialing back the years, and noting the numbers on the solar
> disc, til I got back to zero.  And right there when they displayed
> the transition on June 16, 2002, was this explanation:
> 
> "SUNSPOT ZERO:  This weekend NOAA sunspot region numbers reached
> 9999 and (like a car's odometer) rolled over to 0000.  Sunspot zero
> spans an area equal to approximately 0.5 planet Earths.  It is not
> particularly large or active -- but it will be easy to remember."
> 
> For more information concerning radio propagation, see the ARRL
> Technical Information Service at
> http://arrl.org/propagation-of-rf-signals.  For an explanation of
> the numbers used in this bulletin, see
> http://arrl.org/the-sun-the-earth-the-ionosphere.  An archive of
> past propagation bulletins is at
> http://arrl.org/w1aw-bulletins-archive-propagation.  More good
> information and tutorials on propagation are at http://k9la.us/.
> 
> Monthly propagation charts between four USA regions and twelve
> overseas locations are at http://arrl.org/propagation.
> 
> Instructions for starting or ending email distribution of ARRL
> bulletins are at http://arrl.org/bulletins.
> 
> Sunspot numbers for July 7 through 13 were 25, 55, 63, 46, 62, 63,
> and 54, with a mean of 52.6.  10.7 cm flux was 83.3, 87.1, 92.2,
> 94.4, 94.7, 92.4, and 96.8, with a mean of 91.6.  Estimated planetary
> A indices were 23, 23, 14, 10, 11, 21, and 8, with a mean of 15.7.
> Estimated mid-latitude A indices were 19, 18, 15, 11, 11, 18, and 7
> with a mean of 14.1.
> NNNN
> /EX