Transcript Cycle 24 . . . and More - Frontier Homepage Powered by Yahoo

Cycle 24 . . . and More
Carl Luetzelschwab K9LA
[email protected]
http://mysite.verizon.net/k9la
PVRC Webinar - 19Aug09 - K9LA
What We’re Going to Cover
•
•
•
•
Review of Cycle 23
Generate our own prediction for Cycle 24
Cycle 24 information
Cycle 24 impact to Contesting and DXing
– When Will EU Be Back on the Higher Bands?
– Why Was IARU 2009 So Good?
– Predictions for the Glorioso DXpedition
This presentation will be on the PVRC website
visit http://www.pvrc.org/index.html
click on the ‘PVRC Webinars’ link at the top
PVRC Webinar - 19Aug09 - K9LA
Caveat
• This presentation is from an Amateur Radio perspective
– In other words, mostly related to HF propagation
• The Sun’s solar radiation and the Sun’s disturbances are
important in other ways
–
–
–
–
–
Radiation hazards to astronauts and satellites
Magnetic field activity inducing huge currents at ground level
Orbit mechanics
Impact to climate
Over-the-pole airline flights
• For a broader exposure to solar issues, visit the Marshall
Space Flight Center web site at
http://solarscience.msfc.nasa.gov/
PVRC Webinar - 19Aug09 - K9LA
Speaking of the MSFC . . .
• One of the well-known MSFC solar scientists is Dr. David
Hathaway
– His latest update on Cycle 24 and solar issues was Saturday at
the Huntsville (AL) Hamfest
– If you have a chance to attend one of his presentations, do it!
• Dr. Hathaway’s conclusion “Solar Cycle 24 has begun but is
expected to be very weak”
• His 2009 presentation is the first one on the list at
http://solarscience.msfc.nasa.gov/presentations.shtml
PVRC Webinar - 19Aug09 - K9LA
Meridional flow
• A poleward
magnetic pole
surface flow
• Sinks inward in
the polar regions
• Returns to the
equator at some
depth.
equator
Nandy & Choudhuri (2002)
PVRC Webinar - 19Aug09 - K9LA
A Review of Cycle 23
PVRC Webinar - 19Aug09 - K9LA
Cycle 23
• Began in mid 1996
• Maximum
•
smoothed sunspot
number of 121 in
April 2000
Second peak in
November 2001
– Smoothed sunspot
number of 116
– Great northern
hemisphere 6m F2
openings due to
winter peak
PVRC Webinar - 19Aug09 - K9LA
Daily, Monthly, Smoothed
• Daily sunspot number
(yellow) is very spiky
• Monthly mean sunspot
number (blue) is still spiky
• Smoothed sunspot
number (red) is very
“smooth”
– Official measure of a
sunspot cycle
• The smoothed sunspot
number correlates very
well to monthly median
ionospheric parameters
(foE, foF2, hmF2, etc)
– Our propagation
prediction programs are
based on this correlation
Our propagation predictions are statistical in nature over a month’s time frame
PVRC Webinar - 19Aug09 - K9LA
Cycle 23 Compared to Others
• Early on it was very
Cycle 23 thru December 2008
smoothed sunspot number
Cycle 23
Cycle 20
Cycle 22
Cycle 21
Cycle 19
240
200
160
120
80
40
0
Oct- Oct- Oct- Oct- Oct- Oct- Oct- Oct- Oct- Oct- Oct- Oct- Oct96 97 98 99 00 01 02 03 04 05 06 07 08
PVRC Webinar - 19Aug09 - K9LA
similar to Cycle 20,
which peaked in late
1968
• It was right around the
average maximum of all
previous cycles (which is
a smoothed sunspot
number of 114)
• It’s going longer than
the average duration of
all previous cycles
(which is 10.8 years)
• It is lower at solar
minimum than the
average of all previous
minimums (which is a
smoothed sunspot
number of 6)
smoothed sunspot number
This Solar Minimum
22
20
18
16
14
12
10
8
6
4
2
0
between Cycles 18 and 19
(Apr 1954)
between Cycles 19 and 20
(Nov 1964)
between Cycles 20 and 21
(Jun 1976)
between Cycles 21 and 22
(Sep 1986)
between Cycles 22 and 23
(Oct 1996)
between Cycles 23 and 24
0
5
10
15
20
25
30
35
40
months from descent below smoothed
sunspot number of 20
This solar minimum is unusual compared to other solar minimums in our lifetimes
PVRC Webinar - 19Aug09 - K9LA
A Look at All Historical Data
This solar minimum not that unusual with respect to all other solar minimums (yet!)
PVRC Webinar - 19Aug09 - K9LA
Our Own Prediction for Cycle 24
PVRC Webinar - 19Aug09 - K9LA
Long Term Look at Solar Activity
• Good sunspot records only go back to
the early/mid 1700s
• We can (with reasonable confidence)
reconstruct solar activity from
cosmogenic nuclides
– 10Be in ice cores
– 14C in tree rings
• Cosmogenic nuclides are the result of
galactic cosmic rays
– High energy protons in the 500
MeV to 20 GeV range
– Galactic cosmic rays create
showers of secondary particles,
which eventually includes 10Be and
14C
google “galactic cosmic rays”
and “cosmic ray shower”
PVRC Webinar - 19Aug09 - K9LA
Galactic Cosmic Rays
• The Sun’s magnetic
•
•
•
Since galactic cosmic rays show an inverse
relationship to the sunspot cycle, so do nuclides
PVRC Webinar - 19Aug09 - K9LA
•
field is stronger
during sunspot
maximum
Strong magnetic
field shields Earth
from galactic
cosmic rays
The result is less
nuclides coming to
Earth
Thus nuclides are
low when solar
activity is high
And vice versa –
nuclides are high
when solar activity
is low
Long Term Look at Solar Activity
Remember that high 14C
indicates low solar
activity and vice versa
Cycles 5, 6, 7
There are cycles to solar activity other than the 11-year cycle
PVRC Webinar - 19Aug09 - K9LA
All 23 Cycles
Dalton
Minimum
un-named
Minimum
• We can see those other cycles in this data
• Three maximum periods
–
We’ve lived through the most intense of these three maximum periods
• Two minimum periods
• We appear to be headed for another minimum period
Thus our simple (over-simple?) prediction is for a low Cycle 24
PVRC Webinar - 19Aug09 - K9LA
Next Max vs Previous Min
maximum smoothed
sunspot number of next
solar cycle
Next Solar Max vs Duration of Previous Solar Min
250
R2 = 0.5815
Cycle 19 – short minimum
period before big maximum
200
150
100
50
Where the current
minimum is headed?
0
10
20
30
40
50
60
70
80
90
100
months at solar minimum (smoothed sunspot number < 20)
Trend that also points to a low Cycle 24
PVRC Webinar - 19Aug09 - K9LA
Cycle 24 Information
PVRC Webinar - 19Aug09 - K9LA
Good News - Cycle 24 Has Started
Cycle 24 spots
White is “outward”
magnetic field line
solar
equator
Cycle 23 spots
Black is “inward”
magnetic field line
http://solar-center.stanford.edu/solar-images/magnetograms.html
PVRC Webinar - 19Aug09 - K9LA
Latest Prediction from NOAA
• Solar minimum was in
December 2008
• Maximum of ~ 90 in
mid 2013
• Prior to this recent
prediction, NOAA had
been carrying two
predictions
– One for a “high”
cycle (140)
– One for a “low”
cycle (90)
• Just two predictions?
Nope!
http://www.swpc.noaa.gov/SolarCycle/
PVRC Webinar - 19Aug09 - K9LA
Many Other Predictions
We simply don’t fully understand the processes in the Sun that
generate solar cycles, thus many different methods employed
PVRC Webinar - 19Aug09 - K9LA
Solar Min in Dec 2008 – Really?
• Lack of recent sunspots suggests Cycle 24 will
not be ramping up per the NOAA prediction
– 40 spotless days and counting (http://spaceweather.com)
• More bad news – the Australian IPS (Ionospheric
Prediction Service) has predicted that solar
minimum won’t occur until April 2010
– http://www.ips.gov.au/Solar/1/6
• If we continue to have more spotless days, then
solar minimum could be around a while
Oh, no – April 2010 ! !
PVRC Webinar - 19Aug09 - K9LA
Where Is Cycle 24?
This is the third to the last slide in Dr. Hathaway’s 2009 presentation
PVRC Webinar - 19Aug09 - K9LA
Another Maunder Minimum?
It’s just too early to tell with any confidence
PVRC Webinar - 19Aug09 - K9LA
“Wrong” Cycle 24 Predictions
• Are you frustrated with “wrong” solar cycle predictions?
• Remember what’s happening here
– Solar scientists don’t fully understand the solar cycle process
– They are using the scientific method to put forth theories and
then test their theories with previous cycles and with the
progress (or lack thereof) of Cycle 24
– With solar cycles lasting around 11 years, it’s a slow process
• Many of these theories have predicted past performance
•
(several previous solar cycles) very well
But it’s obvious we’re still missing something
PVRC Webinar - 19Aug09 - K9LA
Minimum between
Cycle 22 and 23
Helioseismology
•
•
•
•
A helioseismic map of the solar
interior. Tilted red-yellow bands
trace solar jet streams. Black
contours denote sunspot activity.
The sun generates new jet streams
near its poles every 11 years
The streams migrate slowly from
the poles to the equator and when
a jet stream reaches the critical
latitude of 22 degrees, new-cycle
sunspots begin to appear
The stream associated with Cycle
24 has moved sluggishly, taking
three years to cover a 10 degree
range in latitude compared to only
two years for the previous solar
cycle.
The jet stream is now, finally,
reaching the critical latitude,
hopefully heralding a return of
solar activity in the months and
years ahead
http://science.nasa.gov/headlines/y2009/17jun_jetstream.htm
PVRC Webinar - 19Aug09 - K9LA
Cycle 24 Impact to Contesting and DXing
PVRC Webinar - 19Aug09 - K9LA
When Is EU Going to Be Back?
• 15m to EU – smoothed
10m may be
back for CQ
WW in 2010
15m may
be back for
ARRL DX in
2010
sunspot number > 25
(10.7 cm smoothed solar
flux > 85)
• 10m to EU - smoothed
sunspot number > 50
(10.7 cm smoothed solar
flux > 100)
• Thus consistent F2
openings to EU may
return for
– 15m in early 2010 (ARRL
DX)
– 10m in late 2010 (CQ
WW)
• To reiterate – this is all
based on Cycle 24
ramping up soon
PVRC Webinar - 19Aug09 - K9LA
Why Was IARU 2009 So Good?
• The week before the
IARU 2009
•
•
http://www.solen.info/solar/
IARU 2009 weekend had
the highest ‘burst’ of
sunspot activity in a long
time
This was coupled with a
low Ap index
The result? Great high
band openings
Qs on the Higher Bands
15m 10m
OL9HQ
1164 815
9A0HQ
1326 700
LY0HQ
1280 756
YR0HQ
1140 851
W1AW/KL7 855 324
PVRC Webinar - 19Aug09 - K9LA
Glorioso DXpedition
• Glorioso is #4 Worldwide Mixed Mode in the
2008 DX Magazine 100 Most Needed Countries
Survey (more details in the Jan/Feb 2009 issue)
PVRC Webinar - 19Aug09 - K9LA
Glorioso - September 2009
• Two delays so far
– 1st attempt - May 2008
– 2nd attempt – July 2009
• If September 2009 happens, could be a better
– Equinox month – higher MUFs
– More sunspots (we can always hope!)
• If they delay even more, then the higher bands
may be productive!
Run predictions using your favorite prediction program
20m will likely be your best band
East Coast will likely have good 17m opportunities, too
PVRC Webinar - 19Aug09 - K9LA
Great Circle Paths to Glorioso
East Coast
Midwest
West Coast
• Glorioso sunrise is 0248 UTC
–
–
–
East Coast has about 3 hours 45 minutes of common darkness
Midwest has about 2 hours 20 minutes of common darkness
West Coast has about 45 minutes of common darkness
–
Lower MUFs, more susceptible to disturbances
• Path goes to progressively higher latitudes as we move West
maps from W6ELProp (free download at www.qsl.net/w6elprop)
PVRC Webinar - 19Aug09 - K9LA
Summary
• I believe solar scientists are headed towards a
consensus that Cycle 24 will be a low one
– This also suggests Cycle 25 will be low
• The question with respect to Cycle 24 is “when
will it start ramping up?”
– The answer: sometime between ‘soon’ and ‘later’
• Regardless of what Cycle 24 does, there will be
lots of DX to work and lots of QSOs to be made
in contests
So get radio-active!
PVRC Webinar - 19Aug09 - K9LA
Q&A
For good technical information and tutorials about solar issues, I highly
recommend the MSFC web site at http://solarscience.msfc.nasa.gov/
This PowerPoint file is at http://mysite.verizon.net/k9la
PVRC Webinar - 19Aug09 - K9LA