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Cycle 24 . . . and More

Cycle 24 . . . and More. Carl Luetzelschwab K9LA k9la@arrl.net http://mysite.verizon.net/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?

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Cycle 24 . . . and More

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  1. Cycle 24 . . . and More Carl Luetzelschwab K9LA k9la@arrl.net http://mysite.verizon.net/k9la PVRC Webinar - 19Aug09 - K9LA

  2. 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

  3. 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

  4. 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

  5. Meridional flow magnetic pole • A poleward surface flow • Sinks inward in the polar regions • Returns to the equator at some depth. equator Nandy & Choudhuri (2002) PVRC Webinar - 19Aug09 - K9LA

  6. A Review of Cycle 23 PVRC Webinar - 19Aug09 - K9LA

  7. 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

  8. 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

  9. Cycle 23 Compared to Others • Early on it was very 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) PVRC Webinar - 19Aug09 - K9LA

  10. This Solar Minimum This solar minimum is unusual compared to other solar minimums in our lifetimes PVRC Webinar - 19Aug09 - K9LA

  11. A Look at All Historical Data This solar minimum not that unusual with respect to all other solar minimums (yet!) PVRC Webinar - 19Aug09 - K9LA

  12. Our Own Prediction for Cycle 24 PVRC Webinar - 19Aug09 - K9LA

  13. 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

  14. Galactic Cosmic Rays • The Sun’s magnetic 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 Since galactic cosmic rays show an inverse relationship to the sunspot cycle, so do nuclides PVRC Webinar - 19Aug09 - K9LA

  15. 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

  16. 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

  17. Next Max vs Previous Min Cycle 19 – short minimum period before big maximum Where the current minimum is headed? Trend that also points to a low Cycle 24 PVRC Webinar - 19Aug09 - K9LA

  18. Cycle 24 Information PVRC Webinar - 19Aug09 - K9LA

  19. 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

  20. 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

  21. 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

  22. 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

  23. Where Is Cycle 24? This is the third to the last slide in Dr. Hathaway’s 2009 presentation PVRC Webinar - 19Aug09 - K9LA

  24. Another Maunder Minimum? It’s just too early to tell with any confidence PVRC Webinar - 19Aug09 - K9LA

  25. “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

  26. Helioseismology Minimum between Cycle 22 and 23 • 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 A helioseismic map of the solar interior. Tilted red-yellow bands trace solar jet streams. Black contours denote sunspot activity. http://science.nasa.gov/headlines/y2009/17jun_jetstream.htm PVRC Webinar - 19Aug09 - K9LA

  27. Cycle 24 Impact to Contesting and DXing PVRC Webinar - 19Aug09 - K9LA

  28. When Is EU Going to Be Back? • 15m to EU – smoothed 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 10m may be back for CQ WW in 2010 15m may be back for ARRL DX in 2010 PVRC Webinar - 19Aug09 - K9LA

  29. Why Was IARU 2009 So Good? IARU 2009 • The week before the 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 15m10m OL9HQ 1164 815 9A0HQ 1326 700 LY0HQ 1280 756 YR0HQ 1140 851 W1AW/KL7 855 324 http://www.solen.info/solar/ PVRC Webinar - 19Aug09 - K9LA

  30. 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

  31. 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

  32. Great Circle Paths to Glorioso • 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 • Path goes to progressively higher latitudes as we move West • Lower MUFs, more susceptible to disturbances East Coast Midwest West Coast maps from W6ELProp (free download at www.qsl.net/w6elprop) PVRC Webinar - 19Aug09 - K9LA

  33. 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

  34. 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

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