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JasonF

Banned

From: Oklahoma

Registered: 2003-11-01

Posts: 12

Re: The Weather on Mars - What drives it compared to earth?

On earth, the oceans and the sun pretty much drive the weather.    Smaller things like terrain features and pressure differences handle most of the rest of it.  Since you have no oceans on mars, what gives rise to these great dust storms?  Some kind of heat engine has to be driving those planet wide storms, but what is it?  The sun is the ultimate source, but what does it work through?  I did a rough search, but it's not up to someone who should be in bed right now.  Good night and I'll leave you with the above questions.  Thanks.

Byron

Member

From: Florida, USA

Registered: 2002-05-16

Posts: 844

Re: The Weather on Mars - What drives it compared to earth?

Although Mars does not have oceans, it still has the heat of the sun and an atmosphere, two ingredients that go together to produce weather. 

Generally, dust storms are created when certain areas of Mars becomes warmer, causing air to rise.  Like on Earth, the planet's rotation causes cyclonic winds to form (i.e., low and high-pressure cells), and these can develop into large dust storms.  From what I know about Mars' atmosphere, whenever there's more dust in the air, it gets warmer by soaking up additional heat from the sun, which causes a feedback cycle to kick in...which can lead to a global dust storm. 

Hope this hlelps 

B

JasonF

Banned

From: Oklahoma

Registered: 2003-11-01

Posts: 12

Re: The Weather on Mars - What drives it compared to earth?

From what I know about Mars' atmosphere, whenever there's more dust in the air, it gets warmer by soaking up additional heat from the sun, which causes a feedback cycle to kick in...which can lead to a global dust storm.

I wondered if the dust played a role.  Thanks.

Shaun Barrett

Member

From: Cairns, Queensland, Australia

Registered: 2001-12-28

Posts: 2,843

Re: The Weather on Mars - What drives it compared to earth?

I think the sheer size of the temperature differentials is important, too, in driving the winds on Mars.
    Apparently, most big dust storms originate in the southern hemisphere during summer. The southern summer happens, at the moment, to coincide with Mars' perihelion, so it's short but 'hot' compared to the northern summer which is longer but cooler.
    This kind of hemispheric difference is exacerbated by the huge day/night temperature differences, which may be as great as 110 to 120 deg.C.
    As Byron points out, temperature differences drive the winds and, on Mars ... boy do we get temperature differences!!

    The topographically driven katabatic winds on Mars have the Tharsis Bulge to help them along, too! A chilled mass of air over Tharsis, as it pours down the slopes, eastward along Mariner Valley and northward toward the lowland plains, must pick up a lot of momentum.
    And, without the heat-sink of the oceans we have here, any moderation of temperature differentials is absent.

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Yang Liwei Rocket

Member

Registered: 2004-03-03

Posts: 993

Re: The Weather on Mars - What drives it compared to earth?

yes, the mars stroms have also been seen for the past hundred years. CO2 is the main ingredient, but the atmospheric pressure is about one hundreth of earths. The dust storms cause weathering, the conditions in the past are a mystery. Did mars have water, what was the weather like when Olympus Mons was active?

Some of many questions

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'first steps are not for cheap, think about it...
did China build a great Wall in a day ?' ( Y L R newmars forum member )