We examine the general conditions that must be satisfied by the configuration of the
continents in order that steady state solutions for Neoproterozoic climate exist that are
characterized by heavy continental glaciation but for which a substantial area of open water
in the equatorial region persists. Such solutions have previously been termed “soft snowball”
or “slush ball” to distinguish them from the “hard snowball” solutions that some have
suggested be required to fit the observational constraints. It is found that three conditions are …