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Current global warming results in an uptake of heat by the Earth system, which is distributed among the different components of the climate system. However, current‐generation climate models deliver heat inventory and partitioning estimates of Earth system components that differ from recent observations. Here we investigate the global heat distribution under warming by using fully‐coupled CMIP6 Earth system model experiments, including a version of the MPI‐ESM with a deep land model component, accommodating the required space for more realistic terrestrial heat storage. The results show that sufficiently deep land models exert increased subsurface land heat uptake, leading to a heat uptake partitioning among the Earth system components that is closer to observational estimates. The results are relevant for the understanding of Earth's heat partitioning and highlight the importance of the land heat sink in the Earth heat inventory. Plain Language Summary: Global warming is associated with heat accumulation in the Earth system due to the intensification of the greenhouse effect. The available heat is distributed unevenly throughout the climate subsystems: the ocean, land, atmosphere, and cryosphere. Overall, the current generation of climate models captures this partitioning well but, on average, shows an overestimation of the ocean heat uptake and an underestimation of the land heat uptake. Previous studies have shown that the lack of heat input into the land comes from structural limitations in the land model components used. In this study, we account for these shortcomings, which greatly improve the land heat uptake in simulations of future climate scenarios. We find that, as a result, the fraction of simulated heat taken up by the ocean is reduced. This leads to a heat distribution among the climate subsystems that is closer to observational estimates. Our results highlight that land heat uptake is relevant for the Earth system heat distribution and that future research should consider modeling approaches including a more realistic land heat sink. Key Points: Considering a sufficient land depth in current‐generation Earth system models facilitates realistic land heat uptake estimates under warmingIncreased land heat uptake leads to an adjusted global heat distribution and a reduced overestimation of simulated ocean heat uptakeThe land heat sink is relevant for the projection of the global energy inventory and its partitioning under global warming [ABSTRACT FROM AUTHOR]

Abstract Current global warming results in an uptake of heat by the Earth system, which is distributed among the different components of the climate system. However, current‐generation climate models deliver heat inventory and partitioning estimates of Earth system components that differ from recent observations. Here we investigate the global heat distribution under warming by using fully‐coupled CMIP6 Earth system model experiments, including a version of the MPI‐ESM with a deep land model component, accommodating the required space for more realistic terrestrial heat storage. The results show that sufficiently deep land models exert increased subsurface land heat uptake, leading to a heat uptake partitioning among the Earth system components that is closer to observational estimates. The results are relevant for the understanding of Earth's heat partitioning and highlight the importance of the land heat sink in the Earth heat inventory.