How temperature-dependent silicate weathering acts as Earth’s geological thermostat

S. L. Brantley, Andrew Shaughnessy, Marina I. Lebedeva, Victor N. Balashov Abstract Earth’s climate may be stabilized over millennia by solubilization of atmospheric carbon dioxide (CO2) as minerals weather, but the temperature sensitivity of this thermostat is poorly understood. We discovered that the temperature dependence of weathering expressed as an activation energy increases from laboratory to watershed as transport, clay precipitation, disaggregation, and fracturing increasingly couple to dissolution. A simple upscaling to the global system indicates that the temperature dependence decreases to ~22 kilojoules per mole because (i) the ...