Spectrum of multiyear wolf number rhythms since 1749: A forecast of solar activity dynamics for the 21st century

Despite the openly polemic nature of our previous article that presented a universal mathematical method for detection of biological and heliogeophysi cal rhythms and critiqued alternative methods of rhythm detection [10], we have not seen so far in the available literature either an analysis of the proposed method or a defense of the results obtained by alternative methods . Yet constructive mathematical methods of rhythm detection are so importan t for further development of heliobiology that this issue deserves serious attention and must not be ignored. In order to invigorate the debate on this topic and channel it toward a dis cussion of specific results obtained by various mathematical methods, we pr esent in this article an analysis of multiyear solar activity rhythms based on the dynamics of Wolf numbers from 1749 to 1992.