Polar Hood

Here we will look at the most dynamic area of Mars. That is because of a constant moisture source, sublimation, and interaction with mid latitudes and water eruptions both vaporous and liquid.

Now I talked about moisture advection with the head, “Rock guy,” Brian

His response:

Moisture advection? Moisture by definition being diffuse wetness or water (or other liquid) causing a slight wetness or dampness? I really don't think so.

Without overrunning moisture advection above artic inversion there would be no Polar Hood. I ain’t letting you off the hook Brian

We will start out soft and slow



Mars is getting more like Earth. This is visible data showing moisture transport or advection. Proof if you will. The good stuff NASA keeps for themselves and then releases. You know they want to read what we say.


Soft and slow



A better definition Brian. Just vapor brother.

Moisture advection:



This is one of the more interesting things I've seen here lately.

You've got my attention.

Most definitions of moisture address liquid and I specifically defined my meaning in using the term in my post. So in the context ice is not moisture and neither is vapour. But I accept your link to wikipedia that indicates that water vapour as a component of the atmospheric properties is moisture advection.

The Martian Polar Hood has been analysed, measured and explained for many decades as has the provenance of both CO2 and water ice clouds and the impact of the Hadley Cell. I appreciate your offer to take it soft and slow in explaining the polar hood, interspersed with your youtube meanderings that have absolutely no place on this forum. I am sure that NASA are on the edge of their seats waiting for your next post.

In RW I think you may have found a soul mate.

Fred, It's SO SIMILAR tou our EARTH environement, that, at first, make me doubt about it's originality.
:shock: :D


I am glad you accept the definition of moisture advection. It will be interesting to see the development of the hood this year. This is one of the best images I have seen.



The laws of physics are the same on Mars as on Earth. The pressures and temperatures however have a significant impact. The other thing that you are not addressing is the fact that unlike Earth, the temperatures of the poles in winter are low enough to cause the atmosphere itself to freeze out. So rather than the Hadley Cell effects dominating as they do on Earth, severely limiting the exchange of atmosphere between hemispheres, on Mars the atmosphere and its constituent elements have to move from pole to pole. This is the reason that the pressure has been dropping at Phoenix during summer as the artmosphere moves south and deposits as dry ice (CO2 snow if you like) on the southern polar regions.

The north pole of Mars isn't the only place where [the pressure] has been [dropping] lately.

Sorry Fred, he set me up to [spike it.]


You are hoeing the same row, again. I never mentioned that there were multiple surface convergence zones. The hemispheric zone you are referring is called the Intra Tropical Convergence Zone on Earth. No such area exist on Mars. I have seen only one transitory artic Jet in satellite imagery. The only surface convergence zones are frontal and transitory in the artic region


Are you saying that Mars does not have Hadley Cells?

The Hadley cells on Mars are present sorta, kinda. The convergence zones are very very weak and moisture starved at the equatorial regions. It does not show on the satellite data as a point of cyclogenesis. The southern highlands complicate the situation even more. The sameness of Mars precludes the development of dissimilar air-masses in this area

The Artic regions are different with permanent High pressure only changing size with ground conditions. An active storm track is visible on satellite data and surface conditions allow for air-mass development and movement.

This is my best guess.



Area I- This is the Artic High that has to be there due to ice pack and thermal gradient. In summer it forms the gust fronts that move down the scarp that NASA calls avalanches. This high weakens and shrinks in the Summer and builds in the winter and produces the NNE winds for Phoenix.

Area IA- This is the upper-level Low pressure that draws air and moisture north over the Artic High. It must be there due to the clouds that form the Polar Hood and thermal dynamics.

Area II- this is a heat low that must form due to changes in solar radiation that reaches the ground outside the Polar Hood and thermal dynamics. This area migrates North in summer to just south of ice pack and south in winter with the Hood.

Area III- This is the Equatorial heat low that forms over migratory max heating zone tied to Solar incidence Unlike Earth no change in air-mass and no storms. How high this are extends or the interaction with the southern highlands is unknown.

Area IV- This is an area of weak convergence and associated low pressure that forms due to rapid cooling at the day-night boundary. Mostly a wind shift. This is an area that can be trumped by storm activity and is more likely in the mid N to mid S latitudes.

Area V- this is the zone of storm activity and air-mass migration. migrates north in Summer and south in Winter. Satellite data says it is here.

The ITCZ like on Earth does not exit on Mars. It is more like the Heat low that forms in the desert SW. and may dissipate at night. The artic region has one true Hadley cell. Cells? Sorta , kinda, maybe.