HOLE IN MARS ATMOSPHERE IS VENTING WATER: A hole has developed in the mars atmosphere that is venting water into space.

This hole is known to open every two years and it allows the planets water to collect at the poles. 

Thats the explanation advanced by a team of Russian and German scientists who studied the odd behavior of water on the Red Planet. Earthbound scientists can see that there's water vapor high in the Martian atmosphere, and that water is migrating to the planet's poles. But now there was no good explanation for how the Martian water cycle works, or why the once-drenched planet is now a dry planet.