The Sun’s Strange Behavior: Maunder Minimum or Gleissberg Cycle?
- 246 Downloads
During the last few years the Sun and solar wind have shown a behavior that was so unexpected that the phenomena was described as “the strange solar minimum”. It has been speculated that the 23/24 solar cycle minimum may have indicated the onset of a Maunder-Minimum-type Grand Minimum. Here we review what is known from 1500 years of proxy data about Maunder-type Grand Minima and the minima of the cyclic Centennial Gleissberg variations. We generate criteria that distinguish between the two types of event. Applying these criteria to the observed solar terrestrial data we conclude that the unexpected behavior began well before the solar cycle 23/24 minimum. The data do not support the Maunder Minimum conjecture. However, the behavior can be understood as a minimum of the Centennial Gleissberg Cycle that previously minimized in the beginning of the 20th century. We conclude that the Centennial Gleissberg Cycle is a persistent variation that has been present 80% of the time during the last 1500 years and should be explained by solar dynamo theory.
KeywordsObservations Solar cycle
- Ahluwalia, H.S., Ygbuhay, R.C.: 2010, Current forecast for sunspot cycle 24 parameters. In: Maksimovic, M., Issautier, K., Meyer-Vernet, N., Moncuquet, M., Pantellini, F. (eds.) Twelfth International Solar Wind Conference, AIP Conf. Proc. 1216, 671 – 674. Google Scholar
- Chapman, S., Bartels, J.: 1940, Geomagnetism, Oxford Univ. Press, New York. Google Scholar
- Feynman, J.: 1988, Solar, geomagnetic and auroral variability observed in the historic record. In: Stephenson, F.B., Wolfendale, A.W. (eds.) Secular Solar and Geomagnetic Variations in the Last 10 000 Years, NATO ASI Series C 236, 14 – 26. Google Scholar
- Finch, I.D.: 2009, Seasonal and Daily Variations in Geomagnetic Activity. Thesis, Doctor of Philosophy, University of Southampton, Southampton, UK. Google Scholar
- Gleissberg, W.: 1965, The eighty-year solar cycle in auroral frequency numbers. J. Br. Astron. Assoc. 75, 227 – 231. Google Scholar
- Gibson, S.: 2007, Whole heliospheric interval. http://ihy2007.org/WHI/WHI.shtml.
- Keimatsu, M.A.: 1976, A chronology of aurorae and sunspots observed in China, Korea, and Japan. Ann. Sci. 13, 1 – 32. Google Scholar
- Livingston, W., Penn, M.: 2009, Are sunspots different during this solar minimum? EOS 90(30). Google Scholar
- Lockwood, M., Rouillard, A.P., Finch, I., Stamper, R.: 2006, Comment on the IDV index: Its derivation and use in inferring long-term variations of the interplanetary magnetic field strength by Leif Svalgaard and Edward W. Cliver. J. Geophys. Res. 111, A09109ss. Google Scholar
- Mayaud, P.N.: 1973, A hundred year series of geomagnetic data 1868 – 1967, indices aa, storm sudden commencements. IAGA Bull. 33. Google Scholar
- Mewaldt, R.A., Davis, A.J., Lave, K.A., Leske, R.A., Stone, E.C., Wiedenbeck, M.E., Binns, W.R., Christian, E.R., Cummings, A.C., de Nolfo, G.A., Israel, M.H., Labrador, A.W., von Rosenvinge, T.T.: 2010, Record-setting cosmic-ray intensities in 2009 and 2010. Astrophys. J. Lett. 723, 1 – 6. ADSCrossRefGoogle Scholar
- Silverman, S., Feynman, J.: 1980, The changing aurora of the past three centuries. In: Deehr, C.S., Holtet, J.A. (eds.) Exploration of the Polar Upper Atmosphere, Reidel, Dordrecht, 407 – 420. Google Scholar
- Steinberg, J.T., Skoug, R.M., Ryland, P., Kasper, J.C., Maruca, B., Lepri, S.T.: 2010, The recent weakening solar wind as observed by ACE and Wind. AGU Fall Meeting, SH11B-1670. Google Scholar
- Vestine, E.H., Laporte, L., Lange, I., Scott, W.E.: 1947, The Geomagnetic Field, Its Description and Analysis. Carnegie Institution of Washington Publication 580. Google Scholar