Fig. 6

Relative importance of anthropogenic combustion iron and iron from mineral dust. a, b The preindustrial to present-day changes of soluble iron deposition flux were calculated for anthropogenic combustion iron (ΔAN) and iron from dust (ΔDust), and their differences were normalized by total deposition flux of soluble iron for present day (Total) for the a BASE and b NEW simulations. ΔDust was assumed to be half of the soluble iron deposition flux from Dust in present day⁴⁴. Red regions show that anthropogenic combustion iron is more important than iron in dust, in terms of the preindustrial to present-day increases of the soluble iron deposition flux