An apparent `evenodd' cycle distribution in Mt. Wilson `numbers of spots' data
Abstract
Mt. Wilson ‘numbers of spots’ data (as defined in Howard et al., 1984) appear to be distributed according to ‘evenodd’ cycle numbering. Linear fits of annual ‘numbers of spots’ versus annual sunspot number for even and oddnumbered cycles have slopes which are statistically different at the 5% level of significance. The existence of an ‘evenodd’ split in Mt. Wilson ‘numbers of spots’ data may be due either to a real difference in even and oddnumbered cycles on the Sun or to a difference in weather at Mt. Wilson (perhaps, related to the 22yr rhythm of drought in the western United States) during even and oddnumbered cycles, or both. For cycle 22, an evennumbered cycle, the peak ‘numbers of spots’ is estimated to be near 2600.
 Publication:

Solar Physics
 Pub Date:
 July 1986
 DOI:
 10.1007/BF00161350
 Bibcode:
 1986SoPh..106...29W
 Keywords:

 Annual Variations;
 Solar Cycles;
 Sunspots;
 Temporal Distribution;
 Solar Oscillations;
 Statistical Analysis;
 Solar Physics