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.