Hostname: page-component-78c5997874-xbtfd Total loading time: 0 Render date: 2024-11-14T16:58:41.553Z Has data issue: false hasContentIssue false

Regression Model for the 22-year Hale Solar Cycle Derived from High Altitude Tree-ring Data

Published online by Cambridge University Press:  25 April 2016

J. O. Murphy
Affiliation:
Department of Mathematics, Monash University, Clayton, Vic. 3168
H. Sampson
Affiliation:
Department of Mathematics, Monash University, Clayton, Vic. 3168
T. T. Veblen
Affiliation:
Department of Geography, University of Colarado, Boulder, CO 80309, USA
R. Villalba
Affiliation:
Department of Geography, University of Colarado, Boulder, CO 80309, USA

Abstract

Initially some simple analytical properties based on the annual Zürich relative sunspot number are established for the 22-year Hale solar magnetic cycle. Since about AD1850, successive maximum sunspot numbers in a Hale cycle are highly correlated. Also, a regression model for the reconstruction of the 22-year Hale cycle has been formulated from proxy tree-ring data, obtained from spruce trees growing at a high altitude site in White River National Forest in Colorado. Over a considerable fraction of the past 300 years to AD1986, the ring-index time series power spectrum exhibits a strong 22-year periodicity, and more recently a significant spectral peak (at the 95% confidence level) at approximately 11 years. The model shows that the greatest variation in ‘amplitude’ in the magnetic cycle occurs over the early decades of the eighteenth century, when the sample size is small. Thereafter, a nearly constant amplitude is maintained until about AD1880 when a break occurs in both phase correspondence and amplitude, extending over the next three cycles. From AD1950 the signal recovers phase with the solar cycle, with reduced but increasing amplitude.

Type
Solar and Solar System
Copyright
Copyright © Astronomical Society of Australia 1994

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Berger, A., Milice, J. L. and van der Mersch, I., 1990, Phil. Trans. R. Soc. Lond., A330, 529.Google Scholar
Bray, R. J. and Loughead, R. E., 1964, Sunspots, Chapman and Hall, London.Google Scholar
Castagnoli, G. C, Bonino, G. and Provenzale, A., 1991, In The Sun in Time, Sonett, C. P. et al. (eds), University of Arizona Press, Tucson, p. 562.Google Scholar
Damon, P. E. and Sonett, C. P., 1991, In The Sun in Time, Sonett, C. P. et al. (eds), University of Arizona Press, Tucson, p. 360.Google Scholar
Dixon, W. J. (chief editor), Brown, M. B., Engelman, L., Frane, J. W., Hill, M. A., Jennrich, R. I. and Toporek, J. D., 1985, BMDP Statistical Software, University of California Press.Google Scholar
Eddy, J. A., 1976, Science, 192, 1189.Google Scholar
Epstein, S. and Krishnamurthy, R. V., 1990, Phil. Trans. R. Soc. Lond., A330, 427.Google Scholar
Fritts, H. C, 1976, Tree Rings and Climate, Academic, London.Google Scholar
Hamming, R. W., 1989, Digital Filters, Prentice-Hall, New-York.Google Scholar
Murphy, J. O., 1990, Proc. Astron. Soc. Aust., 8, 298.Google Scholar
Priest, E. R., 1982, Solar Magnetohydrodynamics, Reidel, Dordrecht.Google Scholar
Sonett, C. P., and Finney, S. A., 1990, Phil. Trans. R. Soc. Lond., A330, 413.Google Scholar
Sonett, C. P. and Suess, H. E., 1984, Nature, 307, 141.CrossRefGoogle Scholar
Stockton, C. W. and Meko, D. M., 1983, J. Climate Appl. Meteorol., 22, 17.Google Scholar
Veblen, T. T., Hadley, K. S., Reid, M. S. and Rebertus, A. J., 1991a, Can. J. For. Res., 21, 242.Google Scholar
Veblen, T. T., Hadley, K. S., Reid, H. S. and Rebertus, A. J., 1991b, Ecol. Soc. America, 72, 213.Google Scholar