Pnas Science Sessions

How Snowball Earth melted Science Sessions are brief conversations with cutting-edge researchers, National Academy members, and policymakers as they discuss topics relevant to today's scientific community. Learn the behind-the-scenes story of work published in the Proceedings of the National Academy of Sciences (PNAS), plus a broad range of scientific news about discoveries that affect the world around us. In this episode, Shuhai Xiao explores how the Earth emerged from a planetwide glaciation called Snowball Earth. In this episode, we cover: •[00:00] Introduction •[00:48] Geobiologist Shuhai Xiao introduces us to Snowball Earth. •[01:58] Xiao introduces the “plumeworld” hypothesis that describes the end of Snowball Earth. •[03:41] He explains how lithium isotopes in rocks can confirm the plumeworld hypothesis. •[05:54] Xiao explains why dolostone deposits in China were suitable for studying this hypothesis. •[06:53] He talks about the results of the study. •[07:39] He talks about the implications of the stud