Earth’s long-term climate is driven by the cycling of carbon between geologic reservoirs and the surface system of the atmosphere, oceans, and the biosphere. The sustained presence of life and liquid water depends on efficient feedback mechanisms that keep carbon inputs to the surface system by magmatic or metamorphic degassing in balance with carbon sink fluxes, such as silicate mineral weathering and organic carbon burial. Imbalances in the carbon cycle, for example due to the release of carbon during the emplacement of Large Igneous Provinces, potentially result in catastrophic climatic disruptions, biotic crises, and mass extinctions in the oceans as well as on land. However, it remains enigmatic what climatic, geologic, and biologic variables determine the resilience of Earth’s compartments to such a degassing event. Here, we evaluate how the evolutionary adaptation and dispersal capacity of the biosphere affect the temperature anomaly following a massive release of CO2 to Earth’s atmosphere and oceans. To do so, we develop an eco-evolutionary vegetation model in which the biosphere’s potential for primary productivity and plant-mediated enhancement of mineral weathering depends on the degree of adaptation to local environmental conditions and couple it to a deep-time carbon cycle and an intermediate complexity climate model. We observe a strong sensitivity of both, the intensity and duration of temperature changes to the capacity of the biosphere to adapt its temperature niche by evolutionary processes as well as to disperse in geographic space. The interaction between the continental configuration and the distribution of dispersal barriers for the terrestrial vegetation further result in the emergence of novel long-term climatic steady states. A better understanding of biologically driven climate regulation mechanisms in a spatial context may help to explain unresolved changes in temperature over Earth’s history.