SB PROP @ ARL $ARLP014
ARLP014 Propagation de K7RA

ZCZC AP14
QST de W1AW
Propagation Forecast Bulletin 14  ARLP014
> From Tad Cook, K7RA
Seattle, WA  April 1, 2016
To all radio amateurs

SB PROP ARL ARLP014
ARLP014 Propagation de K7RA

Again this week solar indices crept lower. Average daily sunspot numbers
declined 8 points to 20.4, and average daily solar flux went down 2.4 points
to 86.4. Geomagnetic indices softened, with planetary A index down 3 points to
8.9, and mid-latitude A index down 1.2 points to 7.4.

Just one new sunspot appeared since March 17, and that was one week later on
March 24.

Predicted solar flux values from USAF and NOAA saw a major downward shift on
March 28.  Overnight, the predicted average daily solar flux for the 38 days
from April 4 through May 11 dropped from 91.6 to 82.2. You can see this by
downloading the spreadsheet at http://bit.ly/1VOqf9B .

Predicted solar flux is 82 on April 1, 81 on April 2-3, 80 on April 4-5, 75 on
April 6, 80 on April 7-9, 85 on April 10-11, 80 on April 12-17, 85 on April
18-24, 80 on April 25-28, 85 on April 29 through May 2, and 80 on May 3-6.

If the daily solar flux declines to 75 as predicted for April 6, that will be
the lowest flux value since the other side of this solar cycle, when it was
74.8 on November 22, 2010.

Predicted planetary A index is 10, 26 and 18 on April 1-3, then 8, 18, and 14
on April 4-6, 10 on April 7-8, then 5, 15, 24, 22 and 20 on April 9-13, then 8
on April 14-15, and 5 on April 16-22, 12 on April 23-24, 8 on April 25, then 5
on April 26-28, then 25 on April 29-30, 8 on May 1, and 5 on May 2-4. The A
index then rises to 24, 22 and 20 on May 8-10.

> From Petr Kolman, OK1MGW of the Czech Propagation Interest Group:

Geomagnetic activity forecast for the period April 1-27, 2016.

Geomagnetic field will be:

Quiet on April 20-22
Mostly quiet on April 1, 14, 17-19, 27
Quiet to unsettled on April 5-6, 9, 10, 15-16, 25-26
Quiet to active on April 4, 7-8, 13, 23-24
Active to disturbed on April 2-3, 11-12

Increased solar wind from coronal holes are expected on April 1-4, 7-8, 10-13,
and 23-24.

Do you like the new format for the above report? Whether you do, or not, or
don't care, register your opinion at https://www.surveymonkey.com/r/BP9FMTZ

According to Spaceweather.com, "NOAA forecasters estimate a 45 percent chance
of polar geomagnetic storms on April 1 when a CIR is expected to hit Earth's
magnetic field. CIRs (co- rotating interaction regions) are transition zones
between fast and slow-moving solar wind streams. Density gradients and shock
waves inside CIRs often do a good job sparking auroras."

An interesting email exchange between Jon Jones, N0JK and Drew Smith, K3PA.

N0JK wrote:

"I was on 10 meters fixed mobile this afternoon (March 27) playing in the CQ
WPX SSB on 10 meters. Saw this spot by KC0DEB:

ZM3T, March 27, 2026, 2113Z on 28420.0 WPX, KC0DEB

"Around 2050Z I was calling CU2ARA on 10 meters. When I let up on the mic
button I heard 'Japan Kilowatt.' Called again, let up and heard the same. It
sounded like my voice, but shifted down 500 Hz or so, with a 5x5 strength and
a hollow aurora sound.

I called several times to test it -- said my call one time, let up, heard it
every time. An echo??  Went down the band and called CN2AA after working the
CU2. Heard the same deal for a couple of calls, even with just N0JK, then it
was gone by 2100z. Had strong back-scatter on US stations, WX3B was 57 on
backscatter. "Japan Kilowatt" is about 2 seconds. Speed of light = 300,000
km/second.
Earth circumference = 40,000 km. K index 3. Weird. Any ideas?

Suppose someone may have recorded my call and was playing it as DQRM -- but
their timing would have to be good to play it every time I called, and on
different spots on the band and only when the DX was listening, not
transmitting.

The distance for single hop F2 backscatter would be too short. I recall K5CM
tests for backscatter echoes on 6 and 10 meters. They are a fraction of a
second. 10 meters was very loud to the Caribbean and West Africa, as well as
New Zealand. I heard both sides of EC5AN loud (Spain) work ZM4T (New Zealand)
on 10 meters."

On March 28 N0JK commented: "I logged the VK0EK Cordell DXpedition March 28 on
30 meter CW. They had just come up on 30 meters at 0250z and worked them 'down
1 kHz.' My set up is 100 watts and load the rain gutter on our home. Catching
VK0EK in the clear and before the pileup found them was a treat! 30 meters is
an amazing band."

Further, he mentioned: "VK0EK has almost as many CW contacts on 80 as 40, note
40 also has SSB and digital QSOs. 30 meters is their 'money band.'

Over 1,000 contacts on 160 is encouraging.

Only 311 contacts on 10 meters is a concern. SFU today is 88. Spaceweather.com
today notes 'the solar cycle is crashing."'

He also wrote (although I am not sure, he may have copied this from some other
source):

"For the past two years, the sunspot number has been dropping as the sun
transitions from Solar Max to Solar Min. Fewer sunspots means there are fewer
solar flares and coronal mass ejections (CMEs). As the explosions subside, we
deem the sun 'quiet.'

But how quiet is it, really? A widely-held misconception is that space weather
stalls and becomes uninteresting during periods of low sunspot number. In
fact, by turning the solar cycle sideways (see https://www.vsp.u
ar.edu/Heliophysics/pdf/Lika_sideways_SC.pdf ), we see that Solar Minimum
brings many interesting changes. For instance, the upper atmosphere of Earth
collapses, allowing space junk to accumulate around our planet. The
heliosphere shrinks, bringing interstellar space closer to Earth. And galactic
cosmic rays penetrate the inner solar system with relative ease."

How quiet is it? Let's take a look at our 3-month moving average of sunspot
numbers. The average for the three month period centered on February 2016
(including all daily sunspot numbers from January 1 through March 31) was 49.
This is the lowest number seen since January 2011, when it was 35.3.

The moving average peaked in March, 2014 when it was 148.2. Since May 2015 the
averages were 77.7, 76.3, 69.1, 67.5, 64.5, 64.6, 58.5, 55.4, 53.5 and 49.

A nice image of lone sunspot 2526 is at https://www.astrobin.com/243353/G/ .
It was photographed by astrophotographer Alexander Sorokin in his backyard at
Azov, in Rostov oblast in the Russian Federation.

David Moore sent this link to yet another article about superflares. But this
one speculates about bigger flares on distant stars, and wonders if they could
happen here in our solar system. I wouldn't pay much attention to the
speculation in comments at the end of this piece, about our Earth being
overdue for such an event. Seems to me that claiming we are due for another
one is the same logic as the Gambler's Fallacy (see https://en.w
kipedia.org/wiki/Gambler's_fallacy ).

Here is the article:

http://earthsky.org/space/could-our-sun-emit-killer-superflare

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://arr
.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/.

My own archives of the NOAA/USAF daily 45 day forecast for solar flux and
planetary A index are in downloadable spreadsheet format at http
//bit.ly/1VOqf9B and http://bit.ly/1DcpaC5 .

Click on "Download this file" to download the archive, and ignore the security
warning about file format. Pop-up blockers may suppress the download.

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 March 24 through 30 were 25, 24, 23, 23, 23, 13, and 12,
with a mean of 28.4. 10.7 cm flux was 86.5, 85.5, 85.5, 88.2, 87.7, 87.8, and
83.8, with a mean of 88.8.  Estimated planetary A indices were 7, 6, 3, 13,
10, 11, and 12, with a mean of 11.9. Estimated mid-latitude A indices were 7,
6, 2, 10, 9, 8, and 10, with a mean of 8.6.

NNNN
/EX

)\/(ark

Always Mount a Scratch Monkey

... Down with categorical imperative!
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 * Origin:  (1:3634/12.73)