On 02/11/2011 11:32 AM, David Jonsson wrote:
> I had to adjust my calculations again because of failures of the
> previous calculations. It is significantly simplified and the torque
> effect is now much lower than in previous versions. I can no longer
> explain the Venusian winds.
Hi David,
The reason for Venus's atmosphere super rotation is very probably
electromagnetic, caused by interactions with the solar wind. The
(retrograde) super rotation is probably also the cause of Venus's slow
actual spin, i.e. Venus atmosphere's counter rotation has gradually
slowed down the planet, due to (friction based) momentum exchange
between the atmosphere and the surface. If you look at the data, the
surface winds are almost zero, which is consistent with this hypothesis,
i.e. the surface and the lower atmosphere are actually "synchronized".
Have you seen a Marinov ball bearing motor in action? Nice and simple
way to produce rotation with electric fields and thermal stress. Planets
with a dense atmosphere can be thought of as giant ball bearings, the
atmosphere taking the role of the balls, and the planet/core that of the
internal bearing. The external bearing would be the surrounding near
vacuum, which also carries the electromagnetic fields. The
electromagnetic fields are channeled through the planet, due to
conductive reasons, and a (counter) rotation of the atmosphere takes
place. Probably Venus atmosphere is more conductive than that of other
planets, and Venus closeness to the Sun increases the effect.
See:
http://adsabs.harvard.edu/abs/2004cosp...35.4731A
http://www.cgd.ucar.edu/cas/adai/pap..._JGeodyn03.pdf
<http://www.cgd.ucar.edu/cas/adai/papers/Abarca_delRio_etal_JGeodyn03.pdf>
For papers that show a correlation between Earth's atmospheric Angular
momentum (AAM) and Solar Activity (SA). Interestingly, Earth's AAM is
also retrograde in its general tendency, and variations on Earth's AAM
affect Length of Day (LOD) due to conservation of Angular Momentum.
The right thing to do would be to do the calculations, assuming an
initial spin in accordance with Venus's distance to the Sun, and testing
for various atmospheric densities, velocity gradients, Venus's estimated
age, etc. etc.
I don't have the time to do that, but maybe you or other person can do it.
By the way, I don't think those are amazing potential explanations for
super rotation and Venus's slow spin rate, but simple, elegant, and
pretty obvious ones, if you think outside of the standard box.
> One thing I still wonder about is how an equilibrium could be
> established. Since no net rotation acceleration is taking place in the
> gas some counter shear stress is taking place and I wonder if the
> shear stress from the observed shear flow could be balancing the
> effect. This explains why the flow is contrary to derived shear. On
> the other hand that shear is horizontal and the derived stress is
> vertical.
>
> I ask you to visit
> http://arxiv.org/abs/1012.1381
> and tell me what you think, Critique is appreciated as well as
> affirmations.
I'll read it and comment back.
Regards,
Mauro
