This thesis explores the complex interplay between dimethyl sulfide (DMS) emissions, sulfate aerosols, and climate dynamics, focusing predominantly on the Southern Ocean. Understanding the role of dimethyl sulfide in aerosol production and its subsequent impact on climate models is crucial for accurate climate predictions. This thesis addresses the complexity and influence of natural biogenic aerosol production from DMS in the Southern Ocean (40 ◦S to 60 ◦S), a region with high uncertainty in simulating clouds and aerosol in current climate models. Using Earth System Models (ESMs) focusing on the UK Earth System Model (UKESM1-AMIP) addresses the uncertainties associated with DMS sources, emissions, and sulfate chemistry.