Speaker Bios (Current Season)

September 25th, 2025

  Seafloor weathering has been proposed as an important process for regulating planetary climate. The surface temperature-dependent uptake of carbon in oceanic crust has been invoked to help explain the stability of Earth’s climate against increasing solar luminosity and variations in CO2  degassing. Indeed, quantitative carbon cycle models suggest a seafloor weathering thermostat may be necessary to explain the stability of Earth’s climate on Gyr timescales, especially given severe supply-limits to continental weathering when the surface land fraction is small, as may have been the case for much of the Archean. In addition to carbon update by the seafloor, alkalinity consuming "reverse weathering" reactions in marine sediments may have also played an important role in Earth's climate evolution. It has been argued that the silica-rich Precambrian oceans experienced elevated reverse weathering fluxes, thereby resulting in higher pCO2  and a warmer surface climate, particularly during the Proterozoic. Here, I will review recent theoretical evidence for climate regulation via hydrothermal and diagenetic processes on the early Earth, and discuss how future exoplanet observations could inform our understanding of planetary climate regulation more broadly.