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Wind Mars has wind and clouds, and the wind can blow the red dust into dust storms. Dust storms can be seen from Earth and can sometimes cover the entire planet. Water Evidence suggests that Mars had liquid water on its surface in the past. Outflow channels on Mars were formed by ground ice and underground aquifers.
It is supposed that billions of years ago Mars was much warmer and wetter. At that time, carbonates would have formed from water and the carbon dioxide-rich atmosphere. Later the deposits of carbonate would have been buried. The double impact has now exposed the minerals. Earth has vast carbonate deposits in the form of limestone. [67]
Later, wind erosion removed much of the surface layers, but left behind the more resistant deposits. Other ways of making inverted relief might be lava flowing down a stream bed or materials being cemented by minerals dissolved in water. On Earth, materials cemented by silica are highly resistant to all kinds of erosional forces.
The layering is believed to have come from the global warming and cooling cycle on Mars; during cooling periods, water migrated to the poles and formed the ice-water layers, while on subsequent warming, the unthawed ice water was covered by layers of dust and dirt from windstorms on the surface, helping to preserve the ice water. [44] [45]
The clouds formed at a level in the atmosphere that was around −65 °C (−85 °F; 208 K), so the clouds would have to be composed of water-ice, rather than carbon dioxide-ice (CO 2 or dry ice), because the temperature for forming carbon dioxide ice is much lower than −120 °C (−184 °F; 153 K).
However, early in its history Mars may have had conditions more conducive to retaining liquid water at the surface. Mars without a dust storm in June 2001 (on left) and with a global dust storm in July 2001 (on right), as seen by Mars Global Surveyor. Early Mars had a carbon dioxide atmosphere similar in thickness to present-day Earth (1000 hPa ...
Scientists are now proposing a new approach to warm up Earth's planetary neighbor by pumping engineered particles -similar in size to commercially available glitter and made of iron or aluminum ...
[102] [103] Maximum abundance of water vapor (50-70 pr. μm) is found in the northern polar regions in early summer due to the sublimation of water ice in the polar cap. [102] Unlike in Earth's atmosphere, liquid-water clouds cannot exist in the Martian atmosphere; this is because of the low atmospheric pressure.