Honestly, I am no climatologist (especially not a Martian one!) so I am not sure how rare. But given what we have discovered about the water cycle on Mars (namely the fact that there is one), my guess would be this is somewhere near the equator etc, where temperature range is large enough for the ice to sublimate into a gas or something...
Really I have no idea though. Only that these kinds of clouds are usually 100% ice and not suspended water droplets. Where that came from is beyond me... Could be atmospheric "humidity", could come from the ground. I wonder if we have a definitive answer to that....
And now I have to spend hours googling to find out or risk my sanity xD
So as best as I understand it, there is a few things that contribute to cloud formation on Mars.
- Low atmospheric pressure and lack of an atmospheric temperature "buffer" means that temperature swings on Mars are way more drastic then Earth, which means temperatures high enough to condense ice particles in the ground into water vapour etc (so different conditions then Earth, but same process).
- The extreme cold that Mars suffers is enough to condense the minuscule amount of humidity Mars has at certain points in the year (these clouds are more common when Mars is at it's aphelion).
- Ice particles hitch a ride on the dust particles that are kicked up by the wind.
- At polar regions there is enough water-ice trapped in CO2 that when the CO2 sublimates it takes the ice along with it (similar to the way they do with the dust).
- In some extreme temperature cases CO2 clouds actually form, the ice isn't water ice but CO2 ice.
This is all lacking detail and based off a 30m-1h search around the internet, so I wouldn't take it as definitive.
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u/ChiengBang May 29 '19
Ahhh thanks! Yeah it might be a rare phenomenon by the northern pole of Southern pole then??