资源环境科技发展态势分析平台

We propose that the first Neoproterozoic Snowball Earth event, the Sturtian glaciation, was initiated by the injection of sulfate aerosols into the stratosphere. Geochronological data indicate that the Natkusiak magmatic assemblage of the Franklin large igneous province coincided with onset of the Sturtian glaciation. The Natkusiak was emplaced into an evaporite basin and entrained significant quantities of sulfur, which would have led to extensive SO2 and H2S outgassing in hot convective plumes. The largest of these plumes could havepenetrated the tropopause, leading to stratospheric sulfate aerosol formation and an albedo increase sufficient to force a Snowball. Radiative forcing was maximized by the equatorial location of the Franklin and the cool Neoproterozoic background climate, which would have lowered the tropopause height, increasing the rate of stratospheric aerosol injection. Our results have implications for understanding Phanerozoicmass extinctionevents, exoplanet habitability, andaerosolperturbations to the present-day climate.