Spinning up a dust devil on Mars

The dust devil and the details: Spinning up a storm on Mars
A large dust devil towers over the Martian surface on the plain of Amazonis Planitia in 2012. The shadow indicates this dust plume reached a height of 12 miles (20 kilometers) although it was only 140 yards in diameter. Credit: NASA / JPL / University of Arizona photo

Spinning up a dust devil in the thin air of Mars requires a stronger updraft than is needed to create a similar vortex on Earth, according to research at The University of Alabama in Huntsville (UAH).

Early results from this research in UAH's Atmospheric Science Department are scheduled for presentation today at the American Geophysical Union's fall meeting in San Francisco.

"To start a dust devil on Mars you need convection, a strong updraft," said Bryce Williams, an graduate student at UAH. "We looked at the ratio between convection and turbulence to find the sweet spot where there is enough updraft to overcome the low level wind and turbulence. And on Mars, where we think the process that creates a vortex is more easily disrupted by frictional dissipation – turbulence and wind at the surface – you need twice as much convective updraft as you do on Earth."

Williams and UAH's Dr. Udaysankar Nair looked for the sweet spot by combining data from a study of Australian dust devils with meteorological observations collected during the Viking Lander mission. They used that data and a one-dimensional Mars planetary boundary layer model to find thresholds of the ratio between convection and surface friction velocities that identify conditions conducive to forming dust devils.

While dust devils on Earth are seldom more than meteorological curiosities, on Mars they sometimes grow to the size of terrestrial tornados, with a funnel more than 100 meters wide stretching as much as 12 miles above the Martian surface.

Williams and Nair are looking at the effects dust devils have on lifting dust into the Martian atmosphere. Dust in the Martian air and its radiative forcing are important modulators of the planet's climate.

"The Martian air is so thin, has a greater effect on energy transfers in the atmosphere and on the surface than it does in Earth's thick atmosphere," said Nair, an associate professor of atmospheric science. Dust in the Martian air cools the surface during the day and emits long-wave radiation that warms the surface at night.


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Citation: Spinning up a dust devil on Mars (2014, December 19) retrieved 17 August 2019 from https://phys.org/news/2014-12-devil-mars.html
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Dec 19, 2014
MAVEN has found the source of these vortices, and although it's blowing in the "wind" it is not because of convection.

http://phys.org/n...ric.html

Dec 19, 2014
MAVEN has found the source of these vortices, and although it's blowing in the "wind" it is not because of convection
logical fallacy
There is NO evidence in your link supporting an "electric" caused updraft
NOR of MAVEN finding an electric source CAUSING updrafts, which CAUSE dustdevils

in fact, as it was clearly stated in your ARGUMENTS on that link in the comments below... your arguments only show that there is an electric/magnetic field associated WITH the dustdevil

you have STILL NEVER produced any evidence that the CAUSE of the dustdevil is electric or magnetic in nature

Sorry, another epic fail
you do this a LOT
make assumptions that are NOT present

this is the reason your eu is considered pseudoscience as well
you made an assumption
there is NO proof of said assumption of causation
THEREFORE, you are simply posting fallacious comments
(to convince yourself?)

repetition does not equal science OR reality

Dec 21, 2014
There is NO evidence in your link supporting an "electric" caused updraft
NOR of MAVEN finding an electric source CAUSING updrafts, which CAUSE dustdevils

MAVEN detected "ion streams" from the solar wind penetrating into Mars' atmosphere (above article), and although you prefer the story that energy just "disappears" this is not what happens. From what we know about electric discharge, such as lightning, the discharge "attracts" upward leaders to complete the connection.
http://vimeo.com/45803576
We have also been aware of ionic wind since the 1700's.
http://en.wikiped...Ion_wind
So when the scientist claims; "We are beginning to see the links in a chain that begins with solar-driven processes", he is correct. The links must complete a circuit, this is how plasma discharge works, and it is exactly what we are observing. It is myopia and ignorance that causes the blindness to what is should be completely obvious if plasma processes were understood.

Dec 21, 2014
MAVEN detected "ion streams" from the solar wind penetrating into Mars' atmosphere (above article)
@CD
yep. already saw that, but (and you should remember this, because this is a serious flaw in all your eu fantasy conjectures) there is absolutely no evidence supporting your conjecture that they are "formed" by electricity, only that there is elec involved
and although you prefer the story that energy just "disappears"
personal conjecture without evidence
where have i said that?
i follow the evidence, i dont make sh*t up and then say it must be true, which is what you are doing here
The links must complete a circuit, this is how plasma discharge works
how does the above article "prove" that dust devils are created by electricity?
it does not
period

argue till you are blue in the face, but there is no
should be completely obvious if plasma processes were understood
argument being made here
there is no proof the effect is causing the dustdevils

Dec 21, 2014
this is how plasma discharge works
@cd continued
and you are simply stating that is how it works
you have provided zero evidence supporting this conclusion
there is no evidence that you can provide that proves this... therefore your conclusions are fallacious

the articles only show an influence/side effect elec/mag has with ddevils, not a creation force in any way (a link is not prof of creation)

until you can provide a study that proves with empirical evidence, that the "only" way to form a dust devil in ANY environment is with plasma discharge, particles (electric AND neutral) and there is no overwhelming influence from heat, wind or radiation...

then your conjecture stands as proof of fallacy, and proof of delusional belief pushing one to ignore relevant data to support a premiss, no different than religious creationists thinking

it is not of proof of plasma/electric dust devil creation

Dec 28, 2014
this is how plasma discharge works

@cd continued
and you are simply stating that is how it works
you have provided zero evidence supporting this conclusion
there is no evidence that you can provide that proves this... therefore your conclusions are fallacious


You ever tried to weld w/o completing the circuit? It will prove even less fruitful that your last lobotomy.

Dec 30, 2014
this is how plasma discharge works

@cd continued
and you are simply stating that is how it works
you have provided zero evidence supporting this conclusion
there is no evidence that you can provide that proves this... therefore your conclusions are fallacious


You ever tried to weld w/o completing the circuit? It will prove even less fruitful that your last lobotomy.
@cdTROLL
and again, you've provided zero evidence supporting your conclusions
you are making assumptions without evidence and you are assuming causation without evidence

you couldn't even come up with a decent ad hominem to make it marginally funny
it sure failed as far as eliciting an emotional response, so...

perhaps you could try some real science now?
i can give you the links to MIT so you can learn about real physics if you want
http://ocw.mit.edu/index.htm

i hope you absorb something
maybe you could ask for some decent insults too

a truly epic fail

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