Does atmospheric CO₂ police the rate of chemical weathering?

Abstract

A case is made that in the absence of an effective feedback control on the rate of delivery of CaO to the oceans, the CO 2 content of the Earth's atmosphere would have wandered over a large range threatening life either by overheating or by carbon dioxide starvation. In this paper, we defend the suggestion by Walker et al. [1981] that control is exerted by the interaction between the CO 2 content of the atmosphere and the continental weathering rates. We contend that in spite of the arguments raised against it [ Raymo and Ruddiman , 1992; Edmond and Huh , 1997] the CO 2 ‐ chemical weathering feedback is the dominant mechanism that stabilizes the atmospheric carbon dioxide content.