Weather

Reference: Zimbelman, J. and H. Kieffer, Thermal Mapping of the Northern Equatorial and Temperate Latitudes of Mars, J. Geophys. Res., 84, 8239-8288, 1979.

Since Mars is further away from the sun than we are it is obviously going to be a lot colder there. On Mars dust storms are very common and can sometimes can go global, engulfing the planet. Many think that Mars is a dry, desolate planet with no water. They are wrong. Mars does have water on it, but it is just not in liquid form. With the average surface temperature at about -62°C, it is just a bit too cold for liquid water to be present. The minimum surface temperature is about -140°C (Brrrrr!). The maximum surface temperature however, is about -20°C. In order to melt this water the Martian atmosphere has to be thickened up by using chloral floral carbons (CFC's). Releasing a lot of these CFC's would cause global warming. This would lead to the process called terraforming. This water is currently locked up in the northern polar ice cap and under the surface in a layer of hard frost called permafrost. Just because liquid water isn't present now doesn't mean Mars is incapable of having a water cycle. Currently there is a water cycle. The Viking landers observed the surface of Mars over such a long period of time they noticed a frost cycle. These photos below show the same landscape. Note on the right the presence of a very thin layer of frost on the surface.

Clouds seem to be an everyday thing on earth, right? Well they are on Mars too. The Martian atmosphere contains a small amount of water vapor; however, the temperature and pressure is such that the atmosphere is usually close to saturation and produces clouds. Even from Earth based telescopes, clouds have been observed on the surface of Mars. There are many cloud patterns that were seen from the Mariner and Viking spacecraft. Since then they have been classified into various categories.

1. Lee waves are clouds that form in the way of large obstacles such as mountains, ridges, craters and volcanoes. The air in these regions undergoes wavelike movements. Basically the clouds get disrupted by these objects.

2. Wave clouds appear as rows of linear clouds. They are common at the edge of the polar caps.

3. Cyclone clouds occur in the north pole and are caused by escaping heat smashing against winds (right).

4. Cloud streets. These clouds exhibit a double periodicity. They appear as linear rows of cumulus-like, bubble-shaped clouds.

5. Streaky clouds. These clouds have a direction, yet appear sporadically.

6. Fog or ground hazes. Fog usually occurs in low areas such as valleys, canyons and craters. It forms during the coolest times of the day such as dawn and dusk. Sometimes ground haze is caused by dust in the atmosphere; however, if the atmosphere is clear, ground fog can be easily identified.

7. Plumes are elongated clouds. They appear to have a source of rising material and in many case are composed of dust particles (right).

 

 

For the most current weather report on Mars click on the Thumbnail to see current wind patterns and temperature for the side that is facing us now. (courtesy CMEX)

The weather at Sojourner today was moderate with temperatures hovering around minus 76 degrees Fahrenheit. The forecast for the remainder of the Martian day has the high of minus 10 degrees Fahrenheit, cooling overnight to about minus 105 degrees.