biostudies-literatureUnknown122(23)Carrillo JThe Earth system model CLIMBER-2 has been used in past work to successfully reproduce the glacial/interglacial cycles of the Plio-Pleistocene and the Mid-Pleistocene Transition (MPT) from predominantly 40 to 100 ky timescale oscillatory behavior as a function of declining volcanic outgassing and regolith removal. In this study, we further examine the sensitivity of this previous work to varying prescribed levels of volcanic outgassing and regolith extent and the long-term dynamics of the global carbon cycle, affecting the exchange and partitioning of carbon between different Earth system reservoirs and therefore global atmospheric CO₂ concentrations. As volcanic outgassing decreases, CO₂ and land carbon storage decrease, while ocean carbon storage, including CaCO<sub>Proceedings of the National Academy of Sciences of the United States of Americae2427236122https://www.ebi.ac.uk/biostudies/studies/S-EPMC12167983biostudies-literatureSensitivity of simulations of Plio-Pleistocene climate with the CLIMBER-2 Earth System Model to details of the global carbon cycle.PMC12167983Ganopolski AWilleit MMann MECarrillo JChristiansen SAMarinov IfalseSensitivity of simulations of Plio-Pleistocene climate with the CLIMBER-2 Earth System Model to details of the global carbon cycle.The Earth system model CLIMBER-2 has been used in past work to successfully reproduce the glacial/interglacial cycles of the Plio-Pleistocene and the Mid-Pleistocene Transition (MPT) from predominantly 40 to 100 ky timescale oscillatory behavior as a function of declining volcanic outgassing and regolith removal. In this study, we further examine the sensitivity of this previous work to varying prescribed levels of volcanic outgassing and regolith extent and the long-term dynamics of the global carbon cycle, affecting the exchange and partitioning of carbon between different Earth system reservoirs and therefore global atmospheric CO₂ concentrations. As volcanic outgassing decreases, CO₂ and land carbon storage decrease, while ocean carbon storage, including CaCO<sub>2025-01-01T00:00:00Z2025 Jun2026-06-05T21:31:14.468Z2026-05-22T03:14:45.803ZS-EPMC121679834045598610.1073/pnas.2427236122