[HQRP] Fwd: STORM/AURORA 25-26 SEPT

[Ed Manuel (N5EM)]

>Date:   Tue, 25 Sep 2001 18:34:54 -0600 (MDT)
>Reply-To: na5n@rt66.com
>Sender: owner-qrp-l@Lehigh.EDU
>From: "Paul Harden, NA5N" <na5n@rt66.com>
>To: "Low Power Amateur Radio Discussion" <qrp-l@Lehigh.EDU>
>Subject: STORM/AURORA 25-26 SEPT
>X-To:   qrp-canada@neale.gpfn.sk.ca, qrp-l@lehigh.edu
>X-Cc:   nmqrp@yahoogroups.com,
>         "Prof. Arnaldo Coro Antich" <inforhc@ip.etecsa.cu>
>X-Authentication-Warning: shell.rt66.com: na5n owned process doing -bs
>
>
>Gang,
>I know there are new members on QRP-L, QRP-Canada, etc. that have missed
>some of these solar tutorials over the past couple of years, so this is
>intended primarily for them.
>
>There was a major X-class flare yesterday on the sun.  For the duration
>of this flare, speed of light energy (x-rays and protons) were fired at
>the earth.  This caused poor HF conditions for several hours, but also
>ionized the E and F layers for good skip propagation -- the situation
>that exists right now.  10M is wide open during daylight hours right now.
>
>The flare also spews out gobs of solar mass that travels outward from
>the sun at 800-1200 km/sec.  When it hits the earth about 2 days later,
>it triggers a geomagnetic storm.  The shockwave from yesterdays flare
>hit us today, about 30 hours after the flare, or cooking along quite well.
>This is like a big blast of wind that hits our magnetic field, makes it
>wiggle to generate huge electrical currents.  Those currents also make
>large noise bursts on 10-15MHz and below.  This enhanced noise on the
>lower bands will persist for a couple of days, wednesday being the worse.
>
>This wiggling of our magnetic field, plus the protons from the sun being
>pumped into the solar regions, also produces aurora, or the northern
>lights.  So there is a good chance of seeing aurora tonight in the
>northern US.  The extent of aurora is always difficult to predict and
>often surprises observers.  So even if you live in the middle US
>latitudes, it would be worth taking a look northward tonight around
>10pm to midnite.
>
>Below is portions of todays RSGA report from NOAA, annotated for those
>interested in the interpretation.
>
>SUMMARY: The HIGHER bands are in GREAT shape.  The LOWER bands will be
>experiencing signal loss and enhanced noise.  But nothing so severe to
>stop QRPers from getting on the air.
>
>72, Paul NA5N
>
>On Tue, 25 Sep 2001, Space Environment Center wrote:
> > Joint USAF/NOAA Report of Solar and Geophysical Activity
> > SDF Number 268 Issued at 2200Z on 25 Sep 2001
> > IA.  Analysis of Solar Active Regions and Activity from  24/2100Z
> > to 25/2100Z:  Solar activity was high. Region 9628 (S18W14) produced
> > an M7/1n with associated Type II sweep at 0440 UTC.
>
>A Type II sweep are radio emissions starting around 300MHz and sweeping
>downward into the HF spectrum, caused by the shockwave of the flare
>punching through the sun's magnetic field lines.  Astronomers use this
>information to calculate the approximate speed of the departing shockwave.
>To us other earthlings, it tells us a shockwave is on the way.  This one
>was not as energetic as the X-class flare monday, and will probably hit
>the earth thursday to trigger a minor geomagnetic storm.
>
> > In addition, the region also generated an M2/1n with Type II at 1027 UTC
>
>Ditto.  This flare also produced a shockwave.  Since both these flares
>are near the center of the sun, both shockwaves will contact earth in
>a couple of days.
>
> > IB.  Solar Activity Forecast:  Solar activity is expected to be
> > moderate to high. Both Regions 9628 and 9632 retain the potential
> > for additional M-class activity, and a possible isolated X-class
> > event.
>
>A major flare from these two regions WILL impact earth ... first, HF
>degradation will occur DURING the flare, and the lower HF frequencies
>will experience poor conditions two days later when the shockwave arrives.
>
> > IIA.  Geophysical Activity Summary 24/2100Z to 25/2100Z:
> > The geomagnetic field was quiet until the end of the interval. A
> > shock, presumably related to the flare/CME of 24/1038 UTC, passed
> > ACE at approximately 2003 UTC.
> > The field is now at active
>
>Note that this report, issued at the end of the UTC, is only about 2
>hours after the shockwave hit, and insufficient time for the 3-hour K
>index measurements to be made.  Thus, only ACTIVE conditions were
>measured.  Since this report was issued, the K indices of 5 and 6 are
>being measured across the globe for minor-major storm conditions.
>
> > The proton events at greater than 10 and 100 MeV continue.
>
>The >10 and >100MeV protons are the energetic proton emissions from the
>sun.  These are striking the earth at near the speed of light, and thus
>remain as enhanced ionizing radiation.  This is good in that it is
>ionizing the E and F layer for very reflective layers and a high MUF.
>Good daylight DX propagation exists right now and tomorrow (at least)
>on 20-10M.
>
>BUT ... is IS also wiping out our VE friends, as up north, these protons
>are also ionizing the D-layer, producing a near HF blackout for them.
>This will continue another couple of days for them.  Ditto for the
>extreme southern hemisphere, like southern Australia, etc.  This
>phenomenon is called a "Polar Cap Absorption Event."
>
> > The Polar Cap Absorption event remains in progress.
>
>See?
>
> > IIB.  Geophysical Activity Forecast:  The geomagnetic field is
> > expected to be at major storm levels during the next 24-36 hours,
> > due to the effects of a shock/cme related to the X2/2b flare of
> > 24/1038 UTC. The storm should persist through 27 September. The
> > current proton events are expected to continue for at least the next
> > 24 hours.
>
>The shockwave hit the earth a few hours ago, triggering a geomagnetic
>storm.  However, as we approach night fall in North America, our part of
>the earth turns away from the sun, and hence the solar wind, and storm
>conditions will subside.  40-80M will be extra noisy tonight, but not
>useless.  BUT ... tomorrow at sunrise, North America will rotate again
>into the high solar wind and the storm will elevate to major storm levels.
>Thus, the worse conditions will be on the sunlit side of the planet.  This
>is why NOAA is forecasting MAJOR storming tomorrow ... as "the earth
>turns" back into the solar wind stream.
>
>At 0000UTC 26 SEP, the ESTIMATED A-index is already at 80, or major
>storm conditions.
>
> > PCAF       in progress
>
>As discussed above.  Pretty lousy conditions above/below about 50 degrees
>latitude, and creeping southward/northward.
>
> > IV.  Penticton 10.7 cm Flux
> > Observed           25 Sep 275
>
>Don't miss this opportunity to experience a solar flux of 275 on 10M
>during daylight hours or greyline (as the sun begins to set).  The MUF
>and E/F layer reflectivity maps show excellent reflectivity right now with
>little path loss.  This is the perfect condition for working QRP DX.
>This condition will persist for several days, and will NOT be heavily
>bothered by the geomagnetic storm bothering the lower bands.
>
> > 90 Day Mean        25 Sep 169
>
>The average solar flux has been 169 for the past 3 months, so to say our
>current flux of 275 is an abberation is an understatement.  Enjoy it!!!
>
> > V.  Geomagnetic A Indices
> > Observed Afr/Ap 24 Sep  005/006
> > Estimated Afr/Ap 25 Sep  010/012
> > Predicted Afr/Ap 26 Sep-28 Sep  080/100-040/040-015/015
>                                   ^^^^^^^ ^^^^^^^ ^^^^^^^
>                                     WED    THURS   FRIDAY
>
>Predicted: MAJOR storm tomorrow/wednesday, subsiding to minor storming
>on thursday, and virtually gone by friday.  Again, this effects only
>the lower ham bands, not 20M and above.  30M is in the transition zone,
>and I would suspect DX signals on 30M would be quite nice tonite and
>tomorrow nite, but kinda poor tomorrow during the day.
>
>72, Paul NA5N

Ed Manuel, N5EM	Houston, TX (Harris Co.) EL29
Houston QRP Club, Houston Amateur Television Society
http://www.n5em.com/	 n5em@amsat.org



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