Correspondingauthor:SCorney,AntarcticClimateandEcosystemCo-operativeResearchCentreUniversityofTasmania,PrivateBag80,Hobart,Tasmania,Australia7001([email protected]) The success of the Coupled Model Intercomparison Project has meant that there are a great number of global climate models with model output available for investigating questions regarding climate change. Each of these models have a combination of prescribed variables, that are essential for inclusion in the CMIP5 archive, and optional variables that vary from model to model. In a recent publication we used model output from a standalone sea ice model to determine differences between ice extent and suitable over-winter habitat for Antarctic krill, Euphausia superba in both current climate and under a climate change scenario. Krill habitat was defined using four ice variables, two of which: the ridging rate of sea ice and the short wave solar radiation at the bottom of the ice, are not essential outputs for CMIP5. Crucially the future trajectories of ice extent and krill habitat differed. In this paper we more thoroughly investigate the ability of global climate models to capture the factors that are thought to affect krill distribution and propose a sliding priority of criteria for assessing global climate model output with respect to its ability to project future habitat and thus population success of this keystone species.