On some of the dune fields on Mars, parallel channels, called linear dune gullies, are found. Contrary to their name these gullies are often highly sinuous. In the past, it was believed that these features were formed by debris flow processes driven by liquid water. However, new evidence from satellite images shows that they are active in local spring by a process driven by carbon dioxide ice. The ice forms on the Martian dunes in local winter and...
