Speaker
Description
The solar activity shows not only regular Schwabe cycles every ≈ 11 years but also some long-term variations and secular trends. Among them, we have some extreme cases such as the Maunder Minimum. Such long-term modulations are challenging to capture or analyse, as the space-borne measurements and most of the ground-based observations cover only decades. The scientific community can resolve such difficulties using historical records, especially those for sunspot observations and eclipse observations, as they offer data in centennial timescales. However, the existing reconstructions conflict each other before 1900. Here, we explore several case studies for reconstructions of the past solar activity, putting foci on the major fault lines of the sunspot number recalibrations, namely the Dalton Minimum, the Maunder Minimum, and their neighborhood. We have substantial developments in this field all the way back to 1607 by instrumental sunspot observations and back to -708 by historical eclipse observations. These records allow us to contrast the Maunder Minimum with its aftermath and the Dalton Minimum, emphasizing how peculiar the Maunder Minimum was.