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The K7RA Solar Update

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 (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 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:

  • Quiet on July 16-17, 22, 26, August 2
  • Mostly quiet on July 10, 14-15, 24-25, 31, August 1
  • Quiet to unsettled on July 9, 12-13, 21, 27-28
  • Quiet to active on July 8, 18-20, 23, 29-30, August 3
  • 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 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 to Covington on the HMI Science Nuggets page of the Stanford University website, and found that link from here.

The last time this NASA solar cycle prediction was updated was January 12, 2016, but in this July 6 version 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 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 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 concerning radio propagation. The ARRL website includes an explanation of the numbers used in this bulletin as well as an archive of past propagation bulletins. The website of Carl Luetzelschwab, K9LA, has more information and tutorials on propagation.

Visit the ARRL website for monthly propagation charts between four US regions and 12 overseas locations and for instructions 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. 



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