07/08/2016
Tad Cook, K7RA, Seattle, reports: The recent zero-sunspot period of June 23
through July 4 ended with the appearance of a single sunspot group[1] (2560) on
Tuesday, July 5. Sunspot numbers were 23, 11, and 25, respectively, on July
5-7.
Compared to the previous week, the average daily sunspot number rose from zero
to 4.9. Average daily solar flux declined from 75.6 to 73.1, while the average
planetary A index dropped from 9 to 6.7, and the average mid-latitude A index
declined from 9.1 to 8.3.
Predicted solar flux shows a rising trend for the next few days, with flux
values from USAF/NOAA at 84 and 85 on July 8-9; 86 on July 10-14; 80 on July
15; 74 on July 16; 72 on July 17-30; 74 on July 31-August 12, and 72 on August
13 and beyond.
Predicted planetary A index is 15, 10, 8, and 15 on July 8-11, 12, 8, 5, and 8
on July 12-15; 5 on July 16-18; 15, 12, 10, 8, and 10 on July 19-23; 5 on July
24-27; 8 and 5 on July 28-29; 10 on July 30-31; 5 on August 1-3; 12, 10, 8, and
18 on August 4-7; 12, 8, 10; and 8 on August 8-11, and 5 on August 12-14.
A glance at the STEREO[2] website can offer clues about upcoming activity about
to rotate into view from the other (hidden) side of our Sun. I can see coming
over the 90° eastern horizon (which, counter-intuitively, is on the left side
of the image) are some magnetically complex regions that could offer more
sunspot activity. These appear as white areas in the image, and I am seeing
this at 0800 UTC on July 7, and at 0700 UTC on July 8 I see it has advanced
well over the horizon and has been numbered as sunspot group 2562. The group
2560 is gone, and 2561 is now about to transit over the western side.
The STEREO images are updated frequently and are a good source of real-time
information. At 0° longitude is the area directly facing Earth, and therefore
the most geo-effective. The area directly facing us takes about 4 weeks (about
27.5 days) to transit all the way around the Sun and again reaches its current
position.
At 2352 UTC on July 6, 2016 the Space Weather Services in Australia issued a
geomagnetic warning: "The effect of a co-rotating interaction region and a
high-speed solar wind stream may raise geomagnetic activity to minor storm
levels on 7 and 8 July."
For July 7 they predicted, "Quiet to active with minor storm periods possible."
For July 8, "Unsettled to minor storm."
Sure enough, the planetary A index on July 7 was 23, up from 5 on July 6. Solar
flux rose from 77.1 on July 6 to 83.3 the next day.
F.K. Janda, OK1HH, sends us his geomagnetic outlook: Geomagnetic activity
forecast for the period July 8-August 3, 2016.
The geomagnetic field will be:
o Quiet on July 16-17, 22, 26, August 2
o Mostly quiet on July 10, 14-15, 24-25, 31, August 1
o Quiet to unsettled on July 9, 12-13, 21, 27-28
o Quiet to active on July 8, 18-20, 23, 29-30, August 3
o Active to disturbed on July 11
Increased solar wind from coronal holes is expected on July 8, (10,) 16, 28,
and 30-31. (The figure in parentheses indicates a lower probability of activity
enhancement; reliability of predictions is slightly reduced.)
Here[3] is a Wikipedia entry concerning VE3CC, who developed the first system
to measure 2.8 GHz (10.7 centimeter) noise from the Sun and figured out that
this could serve as a proxy for sunspot measurement. A big advantage was the
ability to measure solar activity when visual observations of the sun were not
practical, such as when the sky is overcast.
I found the reference[4] to Covington on the HMI Science Nuggets page of the
Stanford University website, and found that link from here[5].
The last time this NASA solar cycle prediction was updated was January 12,
2016, but in this July 6 version[6] I find no difference:
This inquiry is from a reader, WA6QBU, in Santa Rose, California:
"Just finished reading your Propagation article and found it very interesting.
I too have been wondering what is going on. I am a casual DXer with simple
equipment. Over this sunspot cycle I've worked 1344 DX stations to date, and in
the past 2 weeks, 16 stations in both Europe and the South Pacific. Mostly this
was with no sunspots and BTW, sometimes stations were coming in from both
directions at the same time. I'm near San Francisco (100 kilometers north) and
near the coast. These are really the strangest conditions I've seen. Any
comments, especially about the two directions at the same time. This is always
after dark here, up until midnight."
I'm unsure how to answer this, but I may assume that this is all on 40 meters
(although his QRZ.com page[7] says he tunes this loop over 80-10 meters and
works the world with 100 W).
I am not sure that hearing stations from opposite directions (especially since
his antenna is not directional) is unusual, but of course only WA6QBU is
familiar with normal propagation from his QTH.
I also do not know how far away these stations are, but when I run an analysis
on W6ELprop using his QTH as the midpoint between my QTH in the State of
Washington and Los Angeles, I can see multiple examples of both LA and Seattle
received at the same time in Northern California.
But it's encouraging that WA6QBU is happy making lots of contacts when there
are no sunspots. In fact, if you use any propagation prediction software and
enter 0 for the sunspot number, you will discover many scenarios in which there
is viable propagation.
Here is a report on Field Day in Puerto Rico, submitted by Angel Santana-Diaz,
WP3GW:
"Field Day was without sunspots, but we had a great network of stations during
the weekend. More than 1000 stations worked, just missed Idaho, Utah, Wyoming,
and Hawaii. Fifteen meters was king during the day."
He also mentioned in a later e-mail that 20 and 40 meters were good during the
evening.
Finally, this news article[8] from Oregon, which seems to get it right
concerning sunspots (or lack of them) and future climate effects.
I see so many articles in the media concerning sunspots that immediately jump
to the Maunder Minimum and the Ice Age, even though a cooler climate effect
would be heavily offset by massive amounts of carbon loaded into the atmosphere
over the past couple of centuries. That's what climatologists have been telling
us for the past few decades.
The ARRL Technical Information Service offers more information[9] concerning
radio propagation. The ARRL website includes an explanation of the numbers[10]
used in this bulletin as well as an archive of past propagation bulletins[11].
The website of Carl Luetzelschwab, K9LA, has more information and tutorials on
propagation[12].
Visit the ARRL website for monthly propagation charts[13] between four US
regions and 12 overseas locations and for instructions[14] for starting or
ending email distribution of ARRL bulletins.
Sunspot numbers for June 30 through July 6 were 0, 0, 0, 0, 0, 23, and 11, with
a mean of 4.9. The 10.7 centimeter flux was 72.9, 72, 70.9, 72.3, 73.8, 72.4,
and 77.1, with a mean of 73.1. Estimated planetary A indices were 6, 7, 9, 9,
7, 4, and 5, with a mean of 6.7. Estimated mid-latitude A indices were 7, 9,
11, 9, 9, 6, and 7 with a mean of 8.3.
[1] http://www.solarham.net/regions/2560.htm
[2] http://stereo.gsfc.nasa.gov/
[3] https://en.wikipedia.org/wiki/Arthur_Covington
[4] http://hmi.stanford.edu/hminuggets/?p=1510#comment-330947
[5] http://hmi.stanford.edu/hminuggets/?p=477
[6] http://solarscience.msfc.nasa.gov/predict.shtml
[7] https://www.qrz.com/db/WA6QBU/
[8] http://koin.com/2016/07/06/there-arent-any-sunspots-on-the-sun-right-now/
[9] http://arrl.org/propagation-of-rf-signals
[10] http://arrl.org/the-sun-the-earth-the-ionosphere
[11] http://arrl.org/w1aw-bulletins-archive-propagation
[12] http://k9la.us/
[13] http://arrl.org/propagation
[14] http://arrl.org/bulletins
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