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ARRL Propagation Bulletin ARLP040 (2003)

ARLP040 Propagation de K7RA

QST de W1AW  
Propagation Forecast Bulletin 40  ARLP040
From Tad Cook, K7RA
Seattle, WA  October 3, 2003
To all radio amateurs 

ARLP040 Propagation de K7RA

This has been a good week for HF propagation.  Not only have we
moved into fall with its associated good HF propagation around the
equinox, but this week also saw rising sunspot and solar flux values
coupled with quieter geomagnetic conditions.

Average daily sunspot numbers rose from the week previous by 33
points to 125.  The average daily solar flux for the week was nearly
15 points higher at 133.6.  Excepting the first day of the reporting
week, when the planetary A index was 28, these numbers settled down
to average only 12--nearly 15 points lower than the previous week.
The quietest days were Sunday through Tuesday, September 28-30.
Even at high latitudes, conditions were stable, with Alaska's
college A index at four on two of the days.

We are now within a solar wind, but it is moderate and probably
won't cause any upset, at least for the next few days.  Predicted
planetary A index for Friday through Sunday, October 3-5, is 12, 10
and 10.  On Monday it could rise to 15, then higher numbers are
predicted, a planetary A index of 20 for October 7-8.  Solar flux is
expected around 120-125 over the next week.

Let's look at the numbers for the third quarter of 2003, which just
ended: Average daily sunspots for July 1 through September 30 were
110.2, slightly higher than the previous quarter.  From the third
quarter of 2002 through the current quarter the average daily
sunspot numbers were 193.5, 152.7, 120.3, 107.3 and 110.2.  That
reflects a definite downward trend with levels relatively unchanged
from the last quarter to the current one.

Average daily solar flux for the same five quarters were 178.1,
164.2, 134.3, 124.2 and 120.8.  No doubt about a smooth downward
slide there.  Propagation this fall will surely not be as good as
last year's as these numbers continue.

Over the past three months, July through September, average monthly
sunspot numbers were 132.8, 114.3 and 82.6.  Average solar flux
numbers for those same months were 127.1, 122.1 and 112.2.

Grim news emerged recently concerning the NOAA Space Environment
Center in Colorado, where most of the data for these bulletins
originates.  I suspect due to some misunderstanding about their
work, the Senate Appropriations Committee wants to eliminate the
Space Environment Center's budget for fiscal year 2004, which
officially began October 1.  The Senate Appropriations Committee
said in a report that NOAA's work should only be terrestrial and not
extend to space, so it's proposing to cut all funding for the SEC.
The House appropriations bill proposes cutting funding by 40
percent, even in the wake of severe cuts during the fiscal year just

The funny thing about the Senate report is that all of the effects
of solar flares and sunspots that concern us are here on Earth.
Claiming that NOAA should ignore the sun because it is in space
seems silly, since the same standard doesn't apply to NOAA's
conventional weather forecasting.  The SEC is a small part of NOAA,
with an annual budget of just 8 million dollars.

There's a story on this subject on the ARRL Web site (see ''Space
Environment Center Funding in Jeopardy''  The Seattle
Post-Intelligencer ran a story in its October 2 editions, and
there's an item on the September 20 Web page,
available in the archive for that date .

I've contacted my representatives in the Senate and House and found
that, as expected, staff members really had no idea what the obscure
sounding Space Environment Center does.  The only hope is that when
the House and Senate committees work out that portion of the budget,
funding for the SEC will somehow be preserved.  You might contact
your representatives to inquire about this.  Members of the Senate
Appropriations Committee are listed on the committee's Web site .

For more information on propagation and an explanation of the
numbers used in this bulletin see the Propagation page on the ARRL
Web site .

Sunspot numbers for September 25 through October 1 were 122, 127,
137, 139, 108, 116 and 126, with a mean of 125.  The 10.7-cm flux
was 132.6, 131.1, 129.7, 137, 135.1, 133 and 136.8, with a mean of
133.6.  Estimated planetary A indices were 28, 17, 9, 6, 7, 7 and
10, with a mean of 12.


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