Abstract
The existence of the 11‐year cycle in solar activity before the Maunder minimum is clearly demonstrated with cosmogenic 10Be in polar ice during 1180‐1500 A.D. For that interval a periodicity of 11.4 ± 0.2 years is found with a high significance level. Indication of a cyclicity that resembles the Hale magnetic cycle is also observed at a lower significance level. A highly variable cyclicity in the band 9.5‐11.5 years is also found in the record of historical aurorae which appears to be well correlated with the 10Be cyclicity for the same time interval. It is concluded that the Schwabe, or 11‐year, cycle and the Hale magnetic cycle were present before and after the Maunder minimum, even though it is not possible to understand the variability of the cycle.
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