User blog comment:David Rain/ATL idea. Odd, but Cool./@comment-3967693-20120609153144

Technically, it wouldn't really be a world, but a universe in which the atoms of water get denser as they freeze, like most substances. A seemingly simple POD (point of divergence). But there's a problem.

As ice forms on say, a lake, the ice would form, and sink as it gets too dense for the water. When it sinks, there would be available room on the top to freeze over too. That piece of ice would sink as well. And as the process continues, eventually the whole lake would freeze over. So whenever the winter comes, all aquatic life forms that arise (even microbes) would never be able to survive. Life as we know it wouldn't have been able to form.

Also, an ice cap is simply a layer of snow that is not able to melt. The snow just continues to pack on itself, until it eventually becomes a large pile of ice. It would really have nothing to do with ice being denser than water. ChrisL123 15:31, June 9, 2012 (UTC)