An Extended Solar Cycle 23 with Deep Minimum Transition to Cycle 24: Assessments and Climatic Ramifications

Ernest M. Agee Department of Earth and Atmospheric Sciences, Purdue University, West Lafayette, Indiana

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Emily Cornett Department of Earth and Atmospheric Sciences, Purdue University, West Lafayette, Indiana

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Kandace Gleason Department of Earth and Atmospheric Sciences, Purdue University, West Lafayette, Indiana

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Abstract

The extended length of solar cycle 23 and the associated deep quiet period (QP) between cycles 23 and 24 have been examined using the international sunspot record from 1755 to 2010. This study has also introduced a QP definition based on a (beginning and ending) mean monthly threshold value of less than 10 for the sunspot number. Features addressed are the length and intensity of cycle 23, the length of the QP and the associated number of spotless days, and the respective relationships between cycle intensity, length, and QP. The length of cycle 23 (153 months) is second only to cycle 4 (164 months), with an average of 132.5 months for the 11-yr cycle. The length of the QP between cycles 23 and 24 ranks eighth, extending from October 2005 through November 2009 (but subject to continued weakness in cycle 24). The number of spotless days achieved within this QP was 751 (and for all days within the transition from cycle 23 to cycle24, a record number of 801 spotless days had been observed through May 2010). Shortcomings of solar-convection-model predictions of sunspot activity and intensity are also noted, including the failure in the initial predictions of cycle-24 onset. The relevance of an extended quiet solar period and the potential reduction of total solar irradiance (TSI) are also discussed, both in the context of climate-model simulations of future climate change as well as with regard to future satellite measurements of TSI.

Corresponding author address: Ernest M. Agee, Dept. of Earth and Atmospheric Sciences, Purdue University, 550 Stadium Mall Dr., West Lafayette, IN 47907-2051. Email: eagee@purdue.edu

Abstract

The extended length of solar cycle 23 and the associated deep quiet period (QP) between cycles 23 and 24 have been examined using the international sunspot record from 1755 to 2010. This study has also introduced a QP definition based on a (beginning and ending) mean monthly threshold value of less than 10 for the sunspot number. Features addressed are the length and intensity of cycle 23, the length of the QP and the associated number of spotless days, and the respective relationships between cycle intensity, length, and QP. The length of cycle 23 (153 months) is second only to cycle 4 (164 months), with an average of 132.5 months for the 11-yr cycle. The length of the QP between cycles 23 and 24 ranks eighth, extending from October 2005 through November 2009 (but subject to continued weakness in cycle 24). The number of spotless days achieved within this QP was 751 (and for all days within the transition from cycle 23 to cycle24, a record number of 801 spotless days had been observed through May 2010). Shortcomings of solar-convection-model predictions of sunspot activity and intensity are also noted, including the failure in the initial predictions of cycle-24 onset. The relevance of an extended quiet solar period and the potential reduction of total solar irradiance (TSI) are also discussed, both in the context of climate-model simulations of future climate change as well as with regard to future satellite measurements of TSI.

Corresponding author address: Ernest M. Agee, Dept. of Earth and Atmospheric Sciences, Purdue University, 550 Stadium Mall Dr., West Lafayette, IN 47907-2051. Email: eagee@purdue.edu

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  • Ammann, C. M., F. Joos, D. S. Schimel, B. L. Otto-Bliesner, and R. A. Tomas, 2007: Solar influence on climate during the past millennium: Results from transient simulations with the NCAR Climate System Model. Proc. Natl. Acad. Sci. USA, 104 , 37133718.

    • Search Google Scholar
    • Export Citation
  • Dikpati, M., G. de Toma, and P. A. Gilman, 2006: Predicting the strength of solar cycle 24 using a flux-transport dynamo-based tool. Geophys. Res. Lett., 33 , L05102. doi:10.1029/2005GL025221.

    • Search Google Scholar
    • Export Citation
  • Feulner, G., and S. Rahmstorf, 2010: On the effect of a new grand minimum of solar activity on the future climate on earth. Geophys. Res. Lett., 37 , L05707. doi:10.1029/2010GL042710.

    • Search Google Scholar
    • Export Citation
  • Fröhlich, C., 2009: Evidence of a long-term trend in solar irradiance. Astron. Astrophys., 501 , L27L30. doi:10.1051/0004-6361/200912318.

    • Search Google Scholar
    • Export Citation
  • Hathaway, D., cited. 2006: Long range solar forecast. [Available online at http://science.nasa.gov/science-news/science-at-nasa/2006/10may_longrange/].

    • Search Google Scholar
    • Export Citation
  • Henson, R., 2010: Looking within the solar minimum. UCAR Magazine, Winter ed., 6–8. [Available online at http://www2.ucar.edu/magazine/features/looking-within-min].

    • Search Google Scholar
    • Export Citation
  • Keating, C. F., 2008: Not to worry: Solar magnetic activity for cycle 24 is increasing. Eos, Trans. Amer. Geophys. Union, 89 .doi:10.1029/2008EO430002.

    • Search Google Scholar
    • Export Citation
  • Livingston, W., and M. Penn, 2009: Are sunspots different during this solar minimum? Eos, Trans. Amer. Geophys. Union, 90 , 257264. doi:10.1029/2009EO300001.

    • Search Google Scholar
    • Export Citation
  • Scafetta, N., and B. J. West, 2006a: Phenomenological solar contribution to the 1900–2000 global surface warming. Geophys. Res. Lett., 33 , L05708. doi:10.1029/2005GL025539.

    • Search Google Scholar
    • Export Citation
  • Scafetta, N., and B. J. West, 2006b: Phenomenological solar signatures in 400 years of reconstructed Northern Hemisphere temperature record. Geophys. Res. Lett., 33 , L17718. doi:10.1029/2006GL027142.

    • Search Google Scholar
    • Export Citation
  • Solomon, S., D. Qin, M. Manning, M. Marquis, K. Averyt, M. M. B. Tignor, H. L. Miller Jr., and Z. Chen, Eds. 2007: Climate Change 2007: The Physical Science Basis. Cambridge University Press, 996 pp.

    • Search Google Scholar
    • Export Citation
  • Wang, Y-M., J. L. Lean, and N. R. Sheeley Jr., 2005: Modeling the sun’s magnetic field and irradiance since 1713. Astrophys. J., 625 , 522538.

    • Search Google Scholar
    • Export Citation
  • White, O. R., W. Livingston, and M. Penn, 2010: Mini Maunder minimum. Extended Abstracts, SORCE Science Meeting, Keystone, CO, Laboratory for Atmospheric and Space Physics, 6B. [Available online at http://lasp.colorado.edu/sorce/news/2010ScienceMeeting/doc/Session6/6b_White_Livingston_i.pdf].

    • Search Google Scholar
    • Export Citation
  • Woods, T. N., and J. Lean, 2007: Anticipating the next decade of the sun–Earth system variations. Eos, Trans. Amer. Geophys. Union, 88 .doi:10.1029/2007EO440001.

    • Search Google Scholar
    • Export Citation
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