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Fig. 10


Panel A) number of auroral nights, NA, in calendar years for observations in Great Britain collated by E. J. Lowe (1870) with the addition of the observations by Thomas Hughes (Harrison 2005) and John Dalton (Dalton 1834) (grey histogram). Annual group sunspot number of Hoyt & Schatten (1998), with the adoption of recent corrections by Vaquero et al. (2011) and Vaquero & Trigo (2014) (black line). Lowes personal copy of his catalogue of natural phenomena (including auroras) was only recently discovered and was compiled completely independently of other catalogues. Yet it shows, like the others, the dearth of sightings during the MM, some events in 1707 and 1708 and the return of regular sightings in 1716. Panel B) annual variation of NA in the same dataset and of RG.

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