Vegetation plays a fundamental role in the climate system, influencing energy exchange, the hydrological cycle and atmospheric composition. At the same time, vegetation dynamics are strongly influenced by climatic conditions, creating complex feedback mechanisms that regulate the Earth’s climate. Representing these interactions between climate and vegetation is essential in climate models, which must realistically simulate vegetation to improve the representation of the simulated climate. This thesis focuses on the Planet Simulator (PlaSim), an Earth system Model of Intermediate Complexity, and on the Simulator for Biospheric Aspects (SimBA), its embedded simple dynamic global vegetation model. SimBA can operate in two modes: in the non-interactive vegetation mode, simulated vegetation does not influence the climate, while in the interactive mode, vegetation influences the climate through four land surface variables: surface albedo, surface roughness, surface conductance and soil water holding capacity.