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Solar flux is around 240, what a luck. After such a long time of less activity, righ now, on the right moment, the sun gets more active. Our chances for a SSW increase! http://solarham.net/regions.htm

Can we really use this as a tool? r=.48 doesnt stand out to me as important. As much as I love solar weather ( I run Accuweather Astronomy Facebook page) I Would like to see higher r squared.  

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I´m not too dissapointed by a R2 of 0.48. Certainly not when crude parameters like solar flux and QBO phase are used in a highly dynamical system. I actually think it's a quite decent correlation. I guess we can use it as a crude predictor. We have to be cautious as we do not know the underlying causal mechanism!

 

Meanwhile, GFS06z shows a slight improvement with regard to previous runs. It shows renewed pressure on the vortex at the end of the run. Wave-1 action?

 

Posted Image

Edited by Ruben Amsterdam
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I don't see the increased solar activity as something positive for cold! It may help to trigger a SSW (although it is not guaranteed) but in the long run it means that the jet stream will be further north and discourage cold outbreaks.

Karyo

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I don't see the increased solar activity as something positive for cold! It may help to trigger a SSW (although it is not guaranteed) but in the long run it means that the jet stream will be further north and discourage cold outbreaks.Karyo

I think when we have a west based QBO then higher solar output tends to favour SSW, or so the stats say. I'm sure one of our many resident experts will give you a far more scientific explanation  than mine however.

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I don't see the increased solar activity as something positive for cold! It may help to trigger a SSW (although it is not guaranteed) but in the long run it means that the jet stream will be further north and discourage cold outbreaks.Karyo

 

Why do you think it will place the jetstream further north?

Can we really use this as a tool? r=.48 doesnt stand out to me as important. As much as I love solar weather ( I run Accuweather Astronomy Facebook page) I Would like to see higher r squared.  

Please take a look at that chart, with a low solar flux, the chance for a SSW during wQBO is low, with a high solar flux the chance grows.

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missing user recretos and its great models 

 

Well, there isn't much for me to post about at the present time. Posted Image

By the way, I am "he", not "it". Posted Image

 

Nevertheless, here is some model output, which pretty much tells a similar story. 

 

NAEFS+CMC

 

Posted Image Posted Image

 

Posted Image Posted Image

 

GEFS Suite

 

Posted Image Posted Image

 

Posted Image Posted Image

 

NOAA Reforecats v2

 

Posted Image Posted Image

 

Other models (with 48h delay):

Posted Image Posted Image Posted Image

 

Posted Image Posted Image

 

Best regards

Edited by Recretos
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The current pattern is driven by the peak in wave 2 activity that has been on the cards for sdome time now. We can see that this has created a split in the vortex from the troposphere upto beyond the middle stratosphere as noted on day 5.

 

http://users.met.fu-berlin.de/~Aktuell/strat-www/wdiag/ec.php?alert=1&level=all&forecast=f120&lng=eng

 

 

The wave activity peaks around this time and wanes only slightly - so there is likely to be a possible stationary wave situation that could result in holding the Scandinavian weak height rises in position for as long as this continues.

 

http://users.met.fu-berlin.de/~Aktuell/strat-www/wdiag/eczm.php?alert=1&forecast=all&var=ha2&lng=eng

 

 

 

This is critical to how quickly the Atlantic train will restore itself, but note even the latest GFS run holds the split in situ at day 10 at 70hPa:

 

Posted ImageNH_HGT_50mb_240.gif

 

and this could prevent the Atlantic reasserting in itself. I suspect that this is why there isthe divergence of model outcome that Ian F in the model thread hints at.                              

 

Whereas the wave 2 activity hasn't completely destroyed the vortex,it has upset it enough  to create the most fascinating period of model watching since this winter began.

 

We may see that the Scandi high waxes and wanes through January and that an increase in wave activity again is needed to achieve a full blown easterly by the end of the month. And I certainly wouldn't rule that out with the monkey nut vortex shape presently.

I think that's one of the primary pieces of the jigsaw through the middle and latter half of January now and, with time are getting to the 'business end' of winter now with regards to what the final third may produce. Clearly we have all and continue to be given another great example of how the developments within the stratosphere can influence and be seen within the troposphere in terms of the split and this potential block to the N and NE through next week allowing for the first possible cold spell of the season. The consolidation of the vortex over E Canada and into Greenland on ECM and GFS outputs does seem as though it would lead to the Atlantic revving up again and 'attacking' any block that does develop for now, so anything sustained in terms of HLB's seems unlikely. 

 

My knowledge of broader +ve and -ve pressure anoms within the northern hem and their relation to possible mountain torque events is, lets say, in a state of development, but I think all eyes will be on the GWO within the next 2 to 3 weeks to see if it gives any indication of what phase it may enter into and whether this may well result in additional wave 1 and perhaps more importantly wave 2 activity;

 

http://www.atmos.albany.edu/student/nschiral/research/gwo/gfsgwo_1.png

 

Regards, Matt.

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Why do you think it will place the jetstream further north?

 

It is believed that low solar activity encourages a southerly tracking jet.

The Met Office acknowledges this and GP was always using it in his seasonal forecasts. 

 

Karyo

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Yes Kayo,history tells us this time and time again, A very complex subject including lag times, the degree of activity, and also the fact that the sun has been very quite over the last few years for saying that we are at the peak Solar Cycle 24.

 

What i will say is, is that any immediate activity will have no effect on our weather. 

Edited by Polar Maritime
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Here is a paper that does not confirm Labitzke's results regarding solar max and SSW in

a westerly QBO.

Posted Imagesolar warming.pdf

 

Yes while there appears to be a trend there are doubts how important it is. Here are notes by Dan Mitchell for the SolarMIP project from a couple of months ago (complete with un-proofread errors!). A lot depends on the reanalysis datasets used.

 

It seems that for the Labizke plots, the result is only signiï¬cant if 1) you use February,

2) you us a period greater than 40 years (but which doesn’t include the ï¬nal 5 years).
The result is not found in any of the CMIP-5 models which have a QBO (4 in total).
Some of these models are biased in their QBO phases such that the spend far longer
in QBO-E than QBO-E (or vice versa).
 
Edited by Interitus
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The latest GFS runs were a variation on the same theme: a recovery of the vortex in combination with warming in the Asian sector.

Good too see EC with simalar warmings at the end of the run. Could this grow into a potent wave-1 attack?

 
Last chart of this 00z run.

 

Posted Image

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The signs have been growing over the last few runs that wave 1 is going to pick up in intensity  - I can't quite work out yet how this will affect the tropospheric pattern - it will very much depend where the vortex displaces too. I much prefer a split in that regard because they tend to be Atlantic/Pacific based.

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The latest GFS runs were a variation on the same theme: a recovery of the vortex in combination with warming in the Asian sector.

Good too see EC with simalar warmings at the end of the run. Could this grow into a potent wave-1 attack?

 
Last chart of this 00z run.

 

Posted Image

Looks like the beginnings of a true SSW. 

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Interesting 100 mb Fi chart from the GFS with the PV moving well North-East of Greenland

and a strong scandi ridge.

 

I wonder if this is what the GloSea5 has picked up on?

 

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Interesting hints in the wee small hours can be gleaned from our 'informed' posters re G4 output. Seems to me reading between the lines that this model stalled temporarily on SSW progression and now has changed again later this week to something altogether more deliberate, intriguing. That's the sum of my detective work and inference, so look forward to something concrete.

 

 

Well the research last year from Zhang et al claims of the CFS that

In particular, the CFSv2 is capable of predicting mid-winter polar stratosphere warming events in the Northern Hemisphere and the timing of the final polar stratosphere warming in spring in both hemispheres 3-4 weeks in advance

 

and also

 

can capture both timing and amplitude of wave activities in the extratropical stratosphere at a lead time longer than 30 days

 

This is impressive on the face of it, but they admit that they cannot capture the location and scale of these waves and the 0.3 level of skill used is low, equivalent to a 12 day 500mb forecast.

These may be useful indicators of trends, but bottom line is that an actual SSW is only accurately forecast within 15 days, and the same goes for the GFS as detailed in this presentation from last year http://www.cpc.ncep.noaa.gov/products/outreach/workshops/CDPW38/1_Monday/2_Afternoon/Long.pdf

There is no reason to believe that the MetO have anything significantly better than NOAA.

 

In any case the climatology of the stratosphere is such that even statistical analysis may provide insights of a similar lead-time. For example the temperature profiles prior to SSW form quite regular patterns which may be used as probability density functions, particularly in the lower-mid stratosphere least influenced by the troposphere directly below and wave breaking higher up. The table below shows the minimum days before SSW for the 90°N 50mb temperatures since the start of the year. The data is from MERRA and comprises 29 SSW (limited to first warmings) and show that while not impossible, it would be unlikely for there to be an SSW before maybe 24th/25th of this month at earliest, a three week lead-time from the 4th.

01/01/14	-2102/01/14	-2103/01/14	-1804/01/14	-2105/01/14	-1906/01/14	-1807/01/14	-17
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