In Search For Water On Mars, Clues From Antarctica

The Dry Valleys, a polar desert site in Antarctica, have long been compared (30 years) to gullies on Mars that show evidence of recent water flow. The water in the Dry Valleys is rich in calcium chloride, which keeps the water from freezing. Eventually, the salt water from melted ground ice comes to the surface, where water evaporates and salt and sediment are left behind. Since the Dry Valleys so closely resemble the gullies and erosional features on Mars, scientists feel that liquid saltwater may actually be flowing beneath the surface of Mars right now. The team currently working on this project plans to continue looking for any other similarities between the Dry Valleys and Mars so that they can solidify the hypothesis that water may currently be on Mars.

http://www.sciencedaily.com/releases/2007/12/071210094326.htm