IN SOME remote polar regions, the ground is decorated with mysterious circles, polygons, islands and stripes made from stones. Puzzled scientists have proposed many mechanisms to explain their origin, but no one could account for all of the different shapes.
Now Mark Kessler and his colleagues at the University of California, Santa Cruz, have developed a computer model that can reproduce all the patterns (
Starting with bare soil randomly scattered with stones, the computer model simulates hundreds of years of winter freezing and summer thawing. Kessler explains that any initial bumps in the soil grow with each cycle. As ice forms on the surface, water is sucked up from the underlying soil by capillary action and more soil is ...
To continue reading this article, subscribe to receive access to all of newscientist.com, including 20 years of archive content.