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Post by nautonnier on Aug 15, 2010 13:24:57 GMT
Hey!! Rossby!! Why'd you stop waving?
That is the question that would be the real one to answer....
How often does the polar vortex reach a stable state?
What causes the change to retrograde waves?
It does seem that this may be one of the fundamentals - perhaps someone reading knows the trigger for these changes?I have lifted this from a post in another thread as it seems interesting So here are some 'Net resources to look at en.wikipedia.org/wiki/Rossby_wavewww.noc.soton.ac.uk/JRD/SAT/Rossby/Rossbyintro.htmlgeosci.uchicago.edu/~nnn/LAB/DEMOS/RossbyWave.htmlwww.ocean.washington.edu/courses/oc512/rossby-waves-gfd109-lec5a-07.pdfThe one thing these all have in common is that they are generic and won't say why the Rossby wave in the mid-latitude jet in the Northern Hemisphere became stationary. Yet this wave in the jet and the positions that it stops at is probably one of the main impacts on climate. So WHY? There must be some research on the reasons the Jet changes position. Recently the jetstreams have been very much closer to the equator than normal with apparently an enlarged polar vortex and squashed Hadley cells. This may be the reason for the lack of hurricanes (so far). Why have the jetstreams moved south and why the standing Rossby wave?
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Post by hairball on Aug 15, 2010 13:59:29 GMT
Piers Corbyn says it's the Sun *shrug*
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Post by poitsplace on Aug 15, 2010 15:50:57 GMT
It seems to be more seasonal now as well. We'll probably find out a bit more about the specifics over the next couple of years. Up until now the remaining mainstream climatologists were the ones that assumed CO2 was the only thing driving the changes in climate. In a few years they'll have come to the realization that most of the changes were natural and work out what had probably moved the jet stream.
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Post by nautonnier on Aug 15, 2010 16:07:39 GMT
Piers Corbyn says it's the Sun *shrug* To quote glc - it would be interesting to know the mechanism  |
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jinki
Level 3 Rank
Posts: 123
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Post by jinki on Aug 16, 2010 13:36:41 GMT
Hey!! Rossby!! Why'd you stop waving?
That is the question that would be the real one to answer....
How often does the polar vortex reach a stable state?
What causes the change to retrograde waves?
It does seem that this may be one of the fundamentals - perhaps someone reading knows the trigger for these changes?I have lifted this from a post in another thread as it seems interesting So here are some 'Net resources to look at en.wikipedia.org/wiki/Rossby_wavewww.noc.soton.ac.uk/JRD/SAT/Rossby/Rossbyintro.htmlgeosci.uchicago.edu/~nnn/LAB/DEMOS/RossbyWave.htmlwww.ocean.washington.edu/courses/oc512/rossby-waves-gfd109-lec5a-07.pdfThe one thing these all have in common is that they are generic and won't say why the Rossby wave in the mid-latitude jet in the Northern Hemisphere became stationary. Yet this wave in the jet and the positions that it stops at is probably one of the main impacts on climate. So WHY? There must be some research on the reasons the Jet changes position. Recently the jetstreams have been very much closer to the equator than normal with apparently an enlarged polar vortex and squashed Hadley cells. This may be the reason for the lack of hurricanes (so far). Why have the jetstreams moved south and why the standing Rossby wave? The southern hemisphere is the opposite, the AAO is at is most positive since records began in 1979. The Antarctic influence has shrunk right back, but this action strengthens the current La Nina. |
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Post by jurinko on Aug 18, 2010 12:04:00 GMT
In a few years they'll have come to the realization that most of the changes were natural and work out what had probably moved the jet stream. There are no doubts, that those 3 additional molecules of CO2 per remaining 100,000 molecules of air since 1988 did it. Here in Europe, cold weather = flow of cold air from north-east, warm weather = flow of warm air from south-west. There are months in my country station record like September, in which the average temperature did not change a bit since 1900, zero trend. Then there are months, like late spring and summer ones, where decadal fluctuations are pretty much visible and well related to AMO. I have yet to see a study, which evaluated the decadal air circulation changes and compared them with measured temperatures, instead of attributing recent warming since 1990 to "greenhouse gases". |
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Post by nautonnier on Aug 18, 2010 12:39:59 GMT
In a few years they'll have come to the realization that most of the changes were natural and work out what had probably moved the jet stream. There are no doubts, that those 3 additional molecules of CO2 per remaining 100,000 molecules of air since 1988 did it. Here in Europe, cold weather = flow of cold air from north-east, warm weather = flow of warm air from south-west. There are months in my country station record like September, in which the average temperature did not change a bit since 1900, zero trend. Then there are months, like late spring and summer ones, where decadal fluctuations are pretty much visible and well related to AMO. I have yet to see a study, which evaluated the decadal air circulation changes and compared them with measured temperatures, instead of attributing recent warming since 1990 to "greenhouse gases". That's because modeling chaotic fluid flow is really really difficult, using a simple radiation equation is easy even if its incorrect. So the atmosphere is considered as a slab with some static effects (or if you are really ambitious a layered slab) and complications like the atmospheric circulation and clouds are reduced to parameters. (Everyone knows you can represent a stochastic system with a simple parameter  ). The important issue is does the model provide the answer that is expected (by the funding agency). That is why I asked what I thought was probably the fundamental question. What caused the alteration in the Rossby waves of the polar vortex? It seems to me that the equatorward movement of the jetststreams and the change in their paths (Rossby waves) is what is driving the global climate. If a stable pattern were set up that blocked the poleward movement of heat energy could that be what triggers ice ages? Is it possible that a relatively stable state could occur that then becomes self generating? I won't find the answers to those questions in a mis-applied Stefan Boltzmann equation. |
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). The important issue is does the model provide the answer that is expected (by the funding agency).