Supersymmetric world from a conservative viewpoint

KooKuu blames this on : "Why is this polar vortex weakening? We think it's because of the gradual heating up of the North Pole. The North Pole is melting." The currently frozen sea ice on the North Pole is melting?

You should examine the work of Vaclav Bucha (Prague, Physics Inst.) and company on geo-magnetics & jet streams. There is a 2002 paper in Science on the 'top-down' drag of the jet streams as well. I will have to look that one up.

Lubos,An off-point climate question. Consider the coupled systems of partial differential equations governing the global atmosphere and ocean basins. Have you an opinion on what mesh size is required in algebraic discretizations in order to adequately resolve the cascade of energy from large to small scales in the turbulent flow? My view is that the current 100 km cells in the non-radial direction are way too large and result in statistical noise overwhelming computations in weather simulations of only weeks or months (hence the global predictions a century out are not based on the full dynamics but rather very simplified models with parameters selected to please overlords).

Dear Tom, I am afraid that the required resolution strongly depends on the question you want to ask; and on the precise numerical method, too.There are clearly patterns in the turbulence etc. that are shorter than 100 km. On the other hand, many of them are inconsequential for many "more global" quantities you may want to calculate. And many of these short-distance patterns and flows may be taken into account if the cells remember the distribution of the speed and pressure etc. in a "smarter way", like in terms of a few Taylor coefficients in the cell.If one wanted a truly realistic simulation, it would have to be 3D - taking the height of the atmosphere as an independent variable into account. In that case, cubic cells would probably be needed and their side should probably be much shorter than the height of the atmosphere, i.e. 10 kilometers or so.I would also add that I think that even if one constructs the best model with a very tiny box size, it will pretty quickly start to deviate due to some exponentially growing "chaotic" effects, so too much brute force may be a useless overkill.

Thank you. From your last paragraph I think we agree that the global warmers’ predictions are mostly BS.

I really don't buy Kaku's idea, seeing as it appears to run counter to actual observed trends that indicate the opposite has been happening associated with global warming.

"You must realize that it's normal for the pressure near the poles to be lower"? Air is sucked into the Vortex from High above (lower than the surrounding pressure) -- near the Surface flows out (higher than surrounding pressure)This is similar to a tornado (and water spout)which sucks at the bottom and expels on top.

Michio Kaku is auditioning, to be included, in the Science Fiction Clown Conferences.http://www.sunnewsnetwork.ca/video/2700762412001

Michio Kaku reminds me of David Suzuki.Out of touch.For example, Michio Kaku thinks CH4 might cause warming amplification.

Hey , MIT offers a course on anthropogenic global warming .They call it science. It seems that crackpots took control of MIT .

UK storms caused by warming displaced jet stream? No, says IPCC guy...http://www.dailymail.co.uk/news/article-2560310/No-global-warming-did-NOT-cause-storms-says-one-Met-Offices-senior-experts.html

"It's mostly a chaotic system controlled by its internal, largely unpredictable processes."Processes are not well understood, but why give up and call it chaotic?Extraterrestrial events drive the system. Wind speeds increase and Jet Streams, move closer to the Equator, in Winter and during Ice Ages. Then, for additional entertainment, Second Law violations.

Perhaps this is more convincing:http://www.youtube.com/watch?v=H-BbPBg3vj8

Impressive graphics. Sea ice is primarily a function of wind, no?

Processes are not well understood, but why give up and call it chaotic?.Why call it chaotic ? Because it is. And it means in no way "giving up".It is just another, much more relevant, paradigm.Non linear dynamics (in popular speak chaos theory) aims at dealing with systems which are neither in equilibrium nor in steady state and where the degrees of freedom are coupled in a non linear way..And this is clearly a huge majority of what is actually happening in the nature.Saying that a system is "chaotic" just means that trajectories in its phase space diverge exponentially with time.Navier Stokes hence weather and associated fluid dynamics have this property and therefore ARE chaotic..The consequences are well known :1) Even if the system is deterministic, e.g obeys some system of non linear PEDs, it is no more deterministically predictable.2) Ergodicity is the major question. If the system is ergodic, there exists an invariant probability distribution giving the probabilities of future states. In that sense this is perfectly analogous to QM - only probabilities may be known. If the system is not ergodic (typical example of a chaotic non ergodic system are the orbits of N bodies with N>2) then even probabilities can no more be predicted.3) The system's orbits in the phase space generally settle on an attractor (topological invariant). Studying the system's dynamics is then equivalent to studying the attractor's topological properties, its stability, its bassin of attraction etc..So there is much to be said and studied even about chaotic systems provided one uses the right theoretical tools.However predicting exact values of observables describing the system's dynamics doesn't belong to the set of things one can say and study about chaotic systems.

"where the degrees of freedom are coupled in a non linear way" -- nonlinear, as the products if a diode mixer (not chaotic, but the result of inputs)"Saying that a system is "chaotic" just means that trajectories in its phase space diverge exponentially with time" -- Then comes down to modeling phase noise?

Year to year changes yes, long-term decline no.

Wrong, as usual.

KooKuu blames this on : "Why is this polar vortex weakening? We think it's because of the gradual heating up of the North Pole. The North Pole is melting." The currently frozen sea ice on the North Pole is melting?

ReplyDeleteYou should examine the work of Vaclav Bucha (Prague, Physics Inst.) and company on geo-magnetics & jet streams. There is a 2002 paper in Science on the 'top-down' drag of the jet streams as well. I will have to look that one up.

ReplyDeleteLubos,

ReplyDeleteAn off-point climate question. Consider the coupled systems of partial differential equations governing the global atmosphere and ocean basins. Have you an opinion on what mesh size is required in algebraic discretizations in order to adequately resolve the cascade of energy from large to small scales in the turbulent flow? My view is that the current 100 km cells in the non-radial direction are way too large and result in statistical noise overwhelming computations in weather simulations of only weeks or months (hence the global predictions a century out are not based on the full dynamics but rather very simplified models with parameters selected to please overlords).

Dear Tom, I am afraid that the required resolution strongly depends on the question you want to ask; and on the precise numerical method, too.

ReplyDeleteThere are clearly patterns in the turbulence etc. that are shorter than 100 km. On the other hand, many of them are inconsequential for many "more global" quantities you may want to calculate. And many of these short-distance patterns and flows may be taken into account if the cells remember the distribution of the speed and pressure etc. in a "smarter way", like in terms of a few Taylor coefficients in the cell.

If one wanted a truly realistic simulation, it would have to be 3D - taking the height of the atmosphere as an independent variable into account. In that case, cubic cells would probably be needed and their side should probably be much shorter than the height of the atmosphere, i.e. 10 kilometers or so.

I would also add that I think that even if one constructs the best model with a very tiny box size, it will pretty quickly start to deviate due to some exponentially growing "chaotic" effects, so too much brute force may be a useless overkill.

Thank you. From your last paragraph I think we agree that the global warmers’ predictions are mostly BS.

ReplyDeleteI really don't buy Kaku's idea, seeing as it appears to run counter to actual observed trends that indicate the opposite has been happening associated with global warming.

ReplyDelete"You must realize that it's normal for the pressure near the poles to be lower"?

ReplyDeleteAir is sucked into the Vortex from High above (lower than the surrounding pressure) -- near the Surface flows out (higher than surrounding pressure)

This is similar to a tornado (and water spout)

which sucks at the bottom and expels on top.

Michio Kaku is auditioning, to be included,

ReplyDeletein the Science Fiction Clown Conferences.

http://www.sunnewsnetwork.ca/video/2700762412001

Michio Kaku reminds me of David Suzuki.

ReplyDeleteOut of touch.

For example, Michio Kaku thinks CH4

might cause warming amplification.

Hey , MIT offers a course on anthropogenic global warming .They call it science. It seems that crackpots took control of MIT .

ReplyDeleteUK storms caused by warming displaced jet stream? No, says IPCC guy...

ReplyDeletehttp://www.dailymail.co.uk/news/article-2560310/No-global-warming-did-NOT-cause-storms-says-one-Met-Offices-senior-experts.html

"It's mostly a chaotic system controlled by its internal, largely unpredictable processes."

ReplyDeleteProcesses are not well understood,

but why give up and call it chaotic?

Extraterrestrial events drive the system. Wind speeds increase and Jet Streams, move closer to the Equator, in Winter and during Ice Ages. Then, for additional entertainment, Second Law violations.

Perhaps this is more convincing:

ReplyDeletehttp://www.youtube.com/watch?v=H-BbPBg3vj8

Impressive graphics. Sea ice is primarily a function of wind, no?

ReplyDelete

ReplyDeleteProcesses are not well understood,

but why give up and call it chaotic?

.

Why call it chaotic ? Because it is. And it means in no way "giving up".

It is just another, much more relevant, paradigm.

Non linear dynamics (in popular speak chaos theory) aims at dealing with systems which are neither in equilibrium nor in steady state and where the degrees of freedom are coupled in a non linear way..

And this is clearly a huge majority of what is actually happening in the nature.

Saying that a system is "chaotic" just means that trajectories in its phase space diverge exponentially with time.

Navier Stokes hence weather and associated fluid dynamics have this property and therefore

AREchaotic..

The consequences are well known :

1) Even if the system is deterministic, e.g obeys some system of non linear PEDs, it is no more deterministically predictable.

2) Ergodicity is the major question. If the system is ergodic, there exists an invariant probability distribution giving the probabilities of future states. In that sense this is perfectly analogous to QM - only probabilities may be known.

If the system is not ergodic (typical example of a chaotic non ergodic system are the orbits of N bodies with N>2) then even probabilities can no more be predicted.

3) The system's orbits in the phase space generally settle on an attractor (topological invariant). Studying the system's dynamics is then equivalent to studying the attractor's topological properties, its stability, its bassin of attraction etc.

.

So there is much to be said and studied even about chaotic systems provided one uses the right theoretical tools.

However predicting exact values of observables describing the system's dynamics doesn't belong to the set of things one can say and study about chaotic systems.

"where the degrees of freedom are coupled in a non linear way" -- nonlinear, as the products if a diode mixer (not chaotic, but the result of inputs)

ReplyDelete"Saying that a system is "chaotic" just means that trajectories in its phase space diverge exponentially with time" -- Then comes down to modeling phase noise?

Year to year changes yes, long-term decline no.

ReplyDeleteWrong, as usual.

ReplyDelete