Continental Weathering as Climate Stabilizer

Conventional wisdom on Earth’s long-term habitability relies on a negative feedback loop among climate, silicate weathering, and atmospheric CO₂ concentrations. Essentially, climate modulates the rate of CO₂ consumption associated with silicate weathering, which in turn stabilizes climate through the greenhouse effect of atmospheric CO₂. This review assesses the efficacy of continental weathering as a climate stabilizer, including the supply of bedrock available for weathering, the influences of atmospheric oxygenation and land-plant colonization on weathering efficiency, and CO₂-emitting weathering processes that may counteract the negative feedback associated with silicate weathering. Basalt weathering plays a key role in mitigating these constraints, as it can sustain a large weathering-derived CO₂ sink and has exhibited a high sensitivity to climatic changes through much of the Earth’s history.