Solar maximum

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The current prediction for Sunspot Cycle 24 gives a smoothed sunspot number maximum of about 66 in the Summer of 2013. The smoothed sunspot number has already reached 67 (in February 2012) due to the strong peak in late 2011 so the official maximum will be at least this high. The smoothed sunspot number has been flat over the last four months. We are currently over four years into Cycle 24. The current predicted and observed size makes this the smallest sunspot cycle since Cycle 14 which had a maximum of 64.2 in February of 1906. NASA

Solar maximum or solar max is a normal period of greatest solar activity in the 11 year solar cycle of the Sun. During solar maximum, large numbers of sunspots appear and the sun's irradiance output grows by about 0.07%.[1] The increased energy output of solar maxima can impact Earth's global climate and recent studies have shown some correlation with regional weather patterns.[citation needed]

At solar maximum, the Sun's magnetic field lines are the most distorted due to the magnetic field on the solar equator rotating at a slightly faster pace than at the solar poles.[citation needed] The solar cycle takes an average of about 11 years to go from one solar maximum to the next, with duration observed varying from 9 to 14 years.

Three recent solar cycles

Large solar flares often occur during a maximum. For example, the Solar storm of 1859 struck the Earth with such intensity that the northern lights could be seen as far south as Rome, approximately 42° north of the equator.

Predictions[edit]

Predictions of a future maximum's timing and strength are very difficult; predictions vary widely. The last solar maximum was in 2000. In 2006 NASA initially expected a solar maximum in 2010 or 2011, and thought that it could be the strongest since 1958.[2] However, more recent projections say the maximum should arrive in autumn of 2013 and be the smallest sunspot cycle since 1906.[3]

Film[edit]

IMAX documentary about solar maximum called Solarmax.[4]

NASA CME documentary X class Corona Mass Ejection 2012-07-14 documentary

Grand solar minima and maxima[edit]

Grand solar maxima occur when several solar cycles exhibit greater than average activity for decades or centuries. Solar cycles still occur during these grand solar maximum periods but the intensity of those cycles are more intense. Grand solar maxima have shown some correlation with global and regional climate changes.

400 year history of sunspot numbers.
Solar minimum events and approximate dates
EventStartEnd
Homeric minimum [5]950BC800BC
Oort minimum (see Medieval Warm Period)10401080
Medieval maximum (see Medieval Warm Period)11001250
Wolf minimum12801350
Spörer Minimum14501550
Maunder Minimum16451715
Dalton Minimum17901820
Modern Maximum1900present

A list of historical Grand minima of solar activity[6] includes also Grand minima ca. 690 AD, 360 BC, 770 BC, 1390 BC, 2860 BC, 3340 BC, 3500 BC, 3630 BC, 3940 BC, 4230 BC, 4330 BC, 5260 BC, 5460 BC, 5620 BC, 5710 BC, 5990 BC, 6220 BC, 6400 BC, 7040 BC, 7310 BC, 7520 BC, 8220 BC, 9170 BC.

See also[edit]

References[edit]

  1. ^ C. D. Camp and K. K. Tung (2007). "Surface warming by the solar cycle as revealed by the composite mean difference projection". Geophysical Research Letters 34: L14703. Bibcode:2007GeoRL..3414703C. doi:10.1029/2007GL030207. Retrieved 20 January 2012. 
  2. ^ "Solar Storm Warning", Science@NASA, 10 March 2006, Accessed 26 Mar. 2010
  3. ^ "NASA/Marshall Solar Physics - Solar Cycle Prediction". NASA. Retrieved 2012-01-13. 
  4. ^ "Solarmax (2000)". IMDB. Seattle, WA, USA: Amazon.com, Inc. Retrieved August 6, 2012. 
  5. ^ Celia Martin-Puertas, Katja Matthes, Achim Brauer, Raimund Muscheler, Felicitas Hansen, Christof Petrick, Ala Aldahan, Göran Possnert & Bas van Geel (April 2, 2012). "Regional atmospheric circulation shifts induced by a grand solar minimum". Nature Geoscience 5 (6): 397–401. Bibcode:2012NatGe...5..397M. doi:10.1038/ngeo1460. 
  6. ^ Usoskin, Ilya G.; Solanki, Sami K.; Kovaltsov, Gennady A. (2007). "Grand minima and maxima of solar activity: new observational constraints" (PDF). Astron. Astrophys. 471 (1): 301–9. arXiv:0706.0385. Bibcode:2007A&A...471..301U. doi:10.1051/0004-6361:20077704.