One comment

1. 8 December 2006 at 9:39 am

   Pooh says:

   Perhaps they are like stretch marks in the ice. As the ice expands as it freezes*, maybe it pushes or pulls on the weaker spots. Or if the green plants below it or still doing a small amount of photosynthesis, that would release some CO2 which might interact w/ the ice?
   Blathering out loud here – I really don’t know.

   *Water becomes denser w/ decreasing temperatures down to 4 degrees C, then it expands and becomes lighter as it turns to ice. Then as the temperature continues to drop, the solid water (ice) will again follow the normal density – temperature relation. The expansion is what makes ice float, thereby allowing life to continue below the ice.