What is the Snowball Earth Hypothesis?
The Snowball Earth hypothesis refers to the idea that at some point during the Earth’s history, specifically during the Cryogenian period (850 to 630 million years ago), the entire surface was frozen over, including the oceans. The Snowball Earth hypothesis is controversial among paleontologists, but many believe it helps explain the presence of glacial deposits at tropical latitudes from this period, as well as other unusual aspects of the Cryogenian geological record. All scientists agree that there were huge glaciations in the Cryogenian period, the disagreement is on whether they became global in extent. The Snowball Earth scenario, if it did indeed occur, is thought to have been initiated by the drifting of continents into an almost exclusively equatorial configuration. This would have caused the rapid weathering of continental rocks, which would have then absorbed large amounts of atmospheric carbon dioxide. As carbon dioxide is a greenhouse gas that plays a crucial role in keepi
The snowball Earth hypothesis is a model that was proposed by Paul Hoffman and his colleagues from Harvard University in 1998 to explain various unusual features of the Neoproterozoic geologic record in terms of a series of severe glaciations of global scale. The term ‘snowball Earth’ was initially coined by Joe Kirschvink (California Institute of Technology) in 1992, but the idea of global glaciation can be traced at least as far back as the 1940s to the work of the Australian geologist Douglas Mawson. Brian Harland (Cambridge University) pioneered the idea that the Neoproterozoic glaciations were widespread in the early 1960s, and later that decade, the Soviet climate modeler Mikhail Budyko (Leningrad Geophysical Observatory) calculated that a runaway glaciation would occur if glaciers reached a certain critical latitude due to the positive feedback on climate of ice albedo.
