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Magnetic Field of the Sun will Flip

  1. Jul 24, 2009 #1
    Magnetic Field of the Sun will Flip I believe some time in November if I am not mistaken. It happens about once every 11 years. I am currently monitoring sites like:

    http://www.swpc.noaa.gov/SWN/sw_dials.html [Broken]
    http://www.srl.caltech.edu/ACE/ASC/DATA/level3/summaries.html

    To monitor the solar output. My question is are there any other sites that will help me to monitor and predict the coming event.
     
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Jul 25, 2009 #2

    Astronuc

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    The Sun Does a Flip
    http://science.nasa.gov/headlines/y2001/ast15feb_1.htm [Broken]

    Ulysses and the Reversal of the Solar Magnetic Field
    http://www.sp.ph.ic.ac.uk/~forsyth/reversal/


    The sun is now at 'solar miniumum'
    http://science.nasa.gov/headlines/y2009/01apr_deepsolarminimum.htm [Broken]
    http://science.nasa.gov/headlines/y2009/17jun_jetstream.htm [Broken]

    The next 'solar maximum' when a field reversal would occur is 2011-2012 - but the sun is having an unusual deep solar minimum.
    http://www.swpc.noaa.gov/SolarCycle/


    See 10 years ago - http://science.nasa.gov/newhome/headlines/ast22jul99_1.htm [Broken]

    The last flip was completed November 2000.
    http://www.nasa.gov/centers/goddard/news/topstory/2003/1120sun_flip.html

    The next flip in an 11-year cycle would be Nov 2011 - give or take - if the current cycle is typical.


    This site might offer the closest to a prediction.
    http://solarscience.msfc.nasa.gov/predict.shtml
    http://solarscience.msfc.nasa.gov/images/magbfly.jpg


    It would be worthwhile to determine when CME's occur historically in the solar cycle.
    http://solarscience.msfc.nasa.gov/CMEs.shtml

    http://www.spaceweather.com/
     
    Last edited by a moderator: May 4, 2017
  4. Jul 25, 2009 #3
    I apologize for leading anyone astray. The next flip in the Sun's magneticx field will occur in 2012. I made the mistake in taking the flip as happening at the minimum instead of the maximum solar activity. So when do you think the minimum solar activity will occur, Nov 2009?
     
  5. Jul 25, 2009 #4

    Astronuc

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    The sun is apparently in a 'deep' or prolonged minimum right now. Activity should start to pick up this month or perhaps during August. I guess we'll just have to follow the activity to see what happens.

    If the activity follows previous trends then the reversal should start sometime during the latter half of 2011.

    I couldn't find a nice concise process outline, i.e., when the reversal begins, how long the process lasts, and when it is considered to be completed. Apparently it takes weeks, based on what I discern from the 'butterfly' plots.

    I am curious about the significance of the current 'deep' or prolonged miniumum. Does it mean that the return to maximum will be steeper than usual, or that the next maximum will be much stronger than usual?

    This certainly bears watching.

    from http://www.swpc.noaa.gov/SolarCycle/

    I believe from the butterfly plots and other citations, the reversal is completed by the peak of the maxima.
     
    Last edited: Jul 25, 2009
  6. Jul 26, 2009 #5

    D H

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    This solar min has in a sense set solar science back to the drawing board. Back in 2006 solar scientists predicted that cycle 24 would be strong and that they would "see the first sunspots of the next cycle appear in late 2006 or 2007—and Solar Max to be underway by 2010 or 2011" (http://science.nasa.gov/headlines/y2006/10mar_stormwarning.htm [Broken]).
    The observation of a short-lived "backward sunspot" on July 31, 2006 (http://science.nasa.gov/headlines/y2006/15aug_backwards.htm [Broken]) led David Hathaway to claim that the next cycle, Solar Cycle 24, should begin "any time now".

    That sunspot was too short-lived to be deemed worthy of even a sunspot number. It took another year and a half before the first cycle 24 sunspot was seen (http://science.nasa.gov/headlines/y2008/10jan_solarcycle24.htm [Broken]). The uptick expected to be seen in 2007 didn't happen. Then in didn't happen in 2008. Cycle 24 was very slow to start, and cycle 23 was hanging on (http://science.nasa.gov/headlines/y2008/28mar_oldcycle.htm [Broken]). Maybe some signs of life in November 2008 (http://science.nasa.gov/headlines/y2008/07nov_signsoflife.htm [Broken])?

    Nope. Solar activity has remained very low for the first half of 2009. The latest sign of life was a sunspot that struggled to form (but failed to do so) on July 24. One problem: It's polarity makes it a member of solar cycle 23 (http://www.spaceweather.com/archive.php?view=1&day=24&month=07&year=2009, see the "Daily Sun" image).


    That boat (activity following previous trends) has already sailed. NASA is much less confident in its predictions:

    An international panel of experts led by NOAA and sponsored by NASA has released a new prediction for the next solar cycle. Solar Cycle 24 will peak, they say, in May 2013 with a below-average number of sunspots.

    ...

    "It turns out that none of our models were totally correct," says Dean Pesnell of the Goddard Space Flight Center, NASA's lead representative on the panel. "The sun is behaving in an unexpected and very interesting way."

    Right now, the solar cycle is in a valley--the deepest of the past century. In 2008 and 2009, the sun set Space Age records for low sunspot counts, weak solar wind, and low solar irradiance. The sun has gone more than two years without a significant solar flare.

    "In our professional careers, we've never seen anything quite like it," says Pesnell. "Solar minimum has lasted far beyond the date we predicted in 2007."​
    (http://science.nasa.gov/headlines/y2009/29may_noaaprediction.htm [Broken])


    The magnetic butterfly diagrams give a better picture of the magnetic field than do the sunspot charts. See http://solarscience.msfc.nasa.gov/images/magbfly.jpg.
    (The 1024x600 image is a bit too large for inclusion directly.) It looks like it takes a year or so for the field at the poles to flip.


    Some solar scientists are proclaiming that this very prolonged minimum represents the start of a Dalton-style, maybe even a Maunder-style minimum. Time will tell.
     
    Last edited by a moderator: May 4, 2017
  7. Jul 26, 2009 #6
    A bit of unrelated question: Will the average temperature of Earth decrease while our sun is at solar minimum? (would be glad to hear "yes", because i hate the heat in the summer).
     
  8. Jul 26, 2009 #7

    Astronuc

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    I was reading something yesterday about an explanation of the present solar minimum. I think this was it, or at least it is similar.

    http://gong.nso.edu/news/solarmystery/
    This butterfly diagram shows a general reduction in the number of sunspots over the last
    http://spd.boulder.swri.edu/solar_mystery/bfly.png

    http://solarscience.msfc.nasa.gov/SunspotCycle.shtml
    http://solarscience.msfc.nasa.gov/predict.shtml

    Current prediction of increased activity in Cy 24.
    http://solarscience.msfc.nasa.gov/images/ssn_predict_l.gif


    Here's an interestin article
    http://solarscience.msfc.nasa.gov/papers/hathadh/HathawayWilsonReichmann1994.pdf

    http://solarscience.msfc.nasa.gov/papers/hathadh/HathawayWilsonReichmann1999.pdf


    See also their papers and presentations, especially the bottom of the page of the latter.
    http://solarscience.msfc.nasa.gov/papers.shtml [Broken]
    http://solarscience.msfc.nasa.gov/presentations.shtml
     
    Last edited by a moderator: May 4, 2017
  9. Aug 31, 2009 #8

    D H

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    The sun has been quiet since a few days before you made that post. If the sun stays quiet today, August 31, it will have tied the 52 day streak without a spot in summer 2008.

    We and all the befuddled solar scientists.

    This cycle doesn't look anything like the last eight cycles. Here is a comparison of the number of spotless days per month for the current cycle versus cycles 16 to 23:

    MonthlySC1623.png


    So far the current minimum looks a lot more like those during cycles 10-15:

    MonthlySC1015.png


    Other solar scientists aren't so convinced. The near complete lack of sunspots in the 2+ months since the article was published gives reason to doubt. What makes 22 latitude such a critical point? That is when the sun started showing spots during solar cycle 23. This is reasoning from a sample size of one.

    Harkening back to your previous post in this thread, "I guess we'll just have to follow the activity to see what happens."


    Given the dearth of activity, that is not an unrelated question at all.

    Gerald A. Meehl, Julie M. Arblaster, Katja Matthes, Fabrizio Sassi, Harry van Loon, "Amplifying the Pacific Climate System Response to a Small 11-Year Solar Cycle Forcing", Science 28 August 2009
    http://www.sciencemag.org/cgi/content/abstract/325/5944/1114
     
  10. Sep 4, 2009 #9

    D H

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    The Sun didn't stay quiet on August 31. Sunspot 1025 appeared. It disappeared the next day. Not much of a sunspot, but enough to stop the streak.

    An interesting article: Are Sunspots Disappearing? http://science.nasa.gov/headlines/y2009/03sep_sunspots.htm [Broken]
    Penn's colleague Bill Livingston of the NSO has been measuring the magnetic fields of sunspots for the past 17 years, and he has found a remarkable trend. Sunspot magnetism is on the decline:

    http://science.nasa.gov/headlines/y2009/images/sunspots/trend3_strip.jpg [Broken]​
    [/URL]

    A linear extrapolation of something that cannot be linear is of course a dangerous thing to do, but nonetheless that is a trend worth watching. NASA has previously hinted that the Sun's anomalous decline might be a sign of a Dalton-like minimum. In the cited article, NASA hints that the decline might be a sign of an even greater dearth of solar activity, the Maunder Minimum, which might have contributed to the Little Ice Age.
     
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