  Using the reconstruction of power input to the magnetosphere given in Paper 1
(arXiv:1708.04904), we reconstruct annual means of geomagnetic indices over the
past 400 years to within a 1-sigma error of +/-20 pc. In addition, we study the
behaviour of the lognormal distribution of daily and hourly values about these
annual means and show that we can also reconstruct the fraction of
geomagnetically-active (storm-like) days and (substorm-like) hours in each year
to accuracies of 50-60 pc. The results are the first physics-based
quantification of the space weather conditions in both the Dalton and Maunder
minima. We predict terrestrial disturbance levels in future repeats of these
minima, allowing for the weakening of Earth's dipole moment.
