7. Conclusions

A comprehensive size-resolving global aerosol model (GLOMAP-mode) has been used to investigate the impact of the 1783–1784 AD Laki eruption on atmospheric chemistry, microphysical processes and the Earth’s climate system. The study presented is the first to investigate the impact of the eruption on microphysical processes and the global cloud condensation nuclei budget. Moreover, in this thesis the potential impact of a future Laki-style eruption has, for the first time, been put quantitatively into a modern societal context. Furthermore, the sensitivity of the global pre-industrial CCN budget to time-averaged volcanic sulphur emissions has been investigated using GLOMAP-mode, which allowed identification of the key chemical and microphysical processes determining the subsequent cloud-radiative effect.