<p><font size="2">Anyone know how thick is the dust over cover of the glaciers?<br /> There have been theories that might be relict glaciers left at near equatorial locations on Mars, but the consensus view is that they should have sublimated away even with a dust over cover.<br /> However with Mars Phoenix showing water ice precipitation occurs in the north polar region that raises the possibility it could very well occur at other locations on Mars thus providing the water precipitation to replenish the glaciers.<br /><br /> ==================================<br /> 01-October-2008, 04:59 PM<br /> RGClark<br /> Senior Member<br /> Join Date: Feb 2004<br /> Location: Philadelphia, PA<br /><br /> ...<br /> Obviously, the important thing here is that it was water ice snow that was shown to be falling at the Phoenix site. The previous observations showed that CO2 snow could fall at the south pole.<br /> This is important because it will suggest the possibility this can be wide spread on Mars, which will have important implications for the Mars water cycle.<br /> Two very key questions it can have application to are the observation of geologically recent glaciers on Mars and the high H2O content from GRS readings even at equatorial locations.<br /> For the first, glaciers normally require precipitation to be active, but these recent glaciers would have been active during the current geological epoch where the possibility of water precipitation has been largely disregarded.<br /> For the second, the question was always asked where could this water have come from for this water at the equator? Answer: because of the extensive and frequent systems of clouds near the equator they could have provided wide spread water deposition near the equator from cloud precipitation.<br /><br /><br /> Bob Clark<br /> ==============================<br />
http://www.bautforum.com/space-exploration/78062-phoenix-mars-extended-mission-6.html#post1334859<br /><br /> </font> </p><p><font size="2"> Notice also that the Hellas basin where some of the still existing glaciers were found is frequently a site of low lying clouds/fogs:<br /><br /> Martian Clouds.<br /> ...<br /> "Fog<br /> Fog often appears in low-lying areas. It typically occurs in the southern hemisphere especially in the Argyre and Hellas basins. It forms frequently in craters. Occasionally, it occurs in higher regions such as Sinus Sabaeus and Solis Planum."<br />
http://www.solarviews.com/eng/marscld.htm#views <br /><br /> Image of fogs over Hellas:<br />
http://www.solarviews.com/raw/mars/fog.gif<br /><br /> Bob Clark</font> </p> <div class="Discussion_UserSignature"> </div>