To understand its role in past changes and anticipate its future impacts, it is necessary to simulate permafrost with numerical models interacting with climate and carbon cycle models. To this end, this thesis will focus on coupling a permafrost model (VAMPER) with a coupled climate-ice sheet-carbon model (iLOVECLIM model). Comparison with existing data for the modern period will validate the coupling. Secondly, simulations of permafrost evolution during past periods and comparison with existing data, particularly in terms of extension, will enable the model to be improved. During glacialinterglacial periods, the student will analyse interactions with climate, in order to assess the role of permafrost in the establishment and melting of the Northern Hemisphere ice caps. The student will also add the carbon cycle to the permafrost model to assess its role in past changes in CO2 and atmospheric δ13C, a proxy for constraining carbon exchange. These developments, coupled with comparisons with paleo reconstructions, will help improve the model and ultimately assess the role of permafrost in future CO2 and climate projections.