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 It has been a rollercoaster for the last week or so. As of 10/27, there was 18.66 total Eurasian SCE as per the week #43 number. I very roughly estimate that it dropped to 16 as of 10/31 after those huge western flank losses. Now it has risen sharply back to 17.75 as of 11/3 (per the week 44 number) after quite large net gains mainly in the western sector since 10/31.

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It has been a rollercoaster for the last week or so. As of 10/27, there was 18.66 total Eurasian SCE as per the week #43 number. I very roughly estimate that it dropped to 16 as of 10/31 after those huge western flank losses. Now it has risen sharply back to 17.75 as of 11/3 (per the week 44 number) after quite large net gains mainly in the western sector since 10/31.

And similar to last year's dip and rebound at end of 44 although way more coverage this year.

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The -QBO during winter has been shown in papers to be correlated with a -AO winter. And the weak/moderate EL Nino/+PDO/-QBO combo is usually a good one for widespread blocking and a -AO.

 

If you isolate winters with an average DJF MEI value of 0.4 to 1.26, basically bordeline weak El Nino to low/mid range moderate El Nino events (likely this year), every year that had an average DJF QBO with a negative phase had an average DJF AO in the negative range. Every year!

1965-66

1958-59

2009-10

1976-77

1979-80

1986-87

1968-69

2002-03

 

The average value of the AO in those 8 years was -1.54. Ranging from -0.39 in 58-59 to -3.422 in 09-10. In all those years except 1 (79-80) the NAO also average negative 79-80 average +0.1.

 

In those 8 winters, 5/8 Decembers had a -AO, 8/8 Januarys, 6/8 Februarys.

 

Also of note we dont have Rutgers data before 1966, but three of the 6 winters in that list ranked in the top 10 for week 42 snow cover, 2009, 2002, 1976. Which finisehd with DJF AO's of -3.4, -0.65, -2.6

 

The EN/PDO/QBO combo had me already thinking a -AO is favored for this winter, the fact that the October snow data is so impressive only leads me to think that this is even more favored and that the odds favor more of a moderate to strong -AO then a weak -AO.

Great research! Thanks a lot for posting.

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The -QBO during winter has been shown in papers to be correlated with a -AO winter. And the weak/moderate EL Nino/+PDO/-QBO combo is usually a good one for widespread blocking and a -AO.

 

If you isolate winters with an average DJF MEI value of 0.4 to 1.26, basically bordeline weak El Nino to low/mid range moderate El Nino events (likely this year), every year that had an average DJF QBO with a negative phase had an average DJF AO in the negative range. Every year!

1965-66

1958-59

2009-10

1976-77

1979-80

1986-87

1968-69

2002-03

 

 

2002-03 QBO in positive phase.

 

Only 1958-59,1968-69 and 1979-80 with TSI high..... like 2014-15.

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2002-03 QBO in positive phase!!!!!

 

Only 1958-59,1968-69 and 1979-80 with TSI high..... like 2014-15!!!!!!

02-03 was negative QBO during the winter but positive during the Fall

D J F

-0.5 -1.39 -1.44

 

But it certainly can be argued, QBO may not have had much a physical correlation to the AO that winter.

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Looks like this is a new blog from Cohen and co. where they provide real-time analysis on the AO - http://www.aer.com/science-research/climate-weather/arctic-oscillation

 

"Arctic Oscillation Analysis and Forecasts

AER scientists provide researchers and enthusiasts real-time insights on one of North America’s and Europe’s leading drivers for extreme and persistent temperature patterns. Authors Judah Cohen, Ph.D., and Jason Furtado, Ph.D., work at Atmospheric and Environmental Research (AER), a division of Verisk Climate."
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02-03 was negative QBO during the winter but positive during the Fall

D J F

-0.5 -1.39 -1.44

 

But it certainly can be argued, QBO may not have had much a physical correlation to the AO that winter.

 

QBO (determined using the wind between 50 and 40 hPa (45 hPa) in January and February) was positive:

 

http://www.geo.fu-berlin.de/en/met/ag/strat/produkte/northpole/index.html

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Fair enough but my analysis looks at 30mb as the standard

http://www.esrl.noaa.gov/psd/data/correlation/qbo.data

 

is the same if it looks at November value, or the intensity on DJF that is not comparable.

 

 

We are in an amazing era for high latitude blocking which is helping to drive the above normal October Eurasian

snow cover extents since 2002. This favorable pattern is in stark contrast to the lack of blocking that

we experienced from the 80's into the early 90's when the October Eurasian snow cover extents were below normal.

 

Strong October high latitude blocking and above normal Eurasian SCE 

 

attachicon.gifSN.png

 

Strong Arctic PV Octobers and low Eurasian SCE 

 

attachicon.gifNBL.png

 

simple reason:

 

it has reduced the thermal gradient equator/pole. :rolleyes:

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  • 2 weeks later...

Cohen has a great paper on the pattern since 2002 with full access.

Warm Arctic, Cold Continents: A Common Pattern Related to Arctic Sea Ice Melt, Snow Advance, and Extreme Winter Weather

Authors | Abstract | Full Article | Citation | References

Fascinating paper regarding the dynamical models inability to forecast long range winter forecast cold anomalies across the continents. Explains a lot with reasoning as to why long range models have stubbornly held on to warm scenarios during low arctic sea ice high SCE SAI falls only to see them fail miserably.
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  • 1 month later...

Absolute Humidity, on 31 Oct 2014 - 11:18 PM, said:snapback.png

Actually I was eyeballing 60 and south. Regardless, SAI will likely take some hit with -3msk. How much of a hit? Comparing the 27th and today does look pretty catastrophic in terms of snow loss. We'll know soon enough.

wow  that  wrong   I mean really  wrong ... its  not a  catastrophe   and 2nd  as  already stated   its the  slope of the line that is important   --   linear regression (best fit line) of all daily data points for the full month of October

Hmmm... Can only hope this is still wrong. 

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After looking at model data and seeing way, way above normal 850's and sfc temperatures being shown over Scandinavia as well as much of E Europe incl. western Russia, I now feel more confident about the massive amount of melting in that area. So, I do expect you'll see losses once your maps update. Furthermore, with that major warm anomaly moving eastward, I'm now thinking there may be some more significant SC losses over the next three days further east, including some south of 60N. Yep, the indices may take a pretty sig. hit from the great levels of recent days. I never knew that following SC could be so fascinating. ;)

 

Bump. Fwiw, this was my initial post (10/28) detailing my concerns about big late Oct. melting. However, as I said, my worries were alleviated by other posters due to the SAI formula being regression based (trend line). I was even told by cfbaggett that this melting was a good sign as it supposedly meant the process initiated by the high Oct. advance up til 10/27 was already in motion. So, I stopped worrying about it fairly soon afterward. 

 No matter what, we still have no reason to necessarily believe that that late Oct. melt had any negative impact at all. IF the SAI fails miserably, it may have nothing to do with that in all fairness. Why would just 3-4 days matter? Thats why regression is used.

 I have a feeling that the SAI will be discussed quite a bit over the next few months if it, indeed, were to fail badly. But there still is time for a strong -AO to take over for much of the winter. So, I'm not yet giving up.

 

Edited several times.

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Bump. Fwiw, this was my initial post (10/28) detailing my concerns about big late Oct. melting. However, as I said, my worries were alleviated by other posters due to the SAI formula being regression based (trend line). I was even told by cfbaggett that this melting was a good sign as it supposedly meant the process initiated by the high Oct. advance up til 10/27 was already in motion. So, I stopped worrying about it fairly soon afterward. 

 No matter what, we still have no reason to necessarily believe that that late Oct. melt had any negative impact at all. IF the SAI fails miserably, it may have nothing to do with that in all fairness. Why would just 3-4 days matter? Thats why regression is used.

 I have a feeling that the SAI will be discussed quite a bit over the next few months if it, indeed, were to fail badly. But there still is time for a strong -AO to take over for much of the winter. So, I'm not yet giving up.

 

Edited several times.

IMO, if it fails badly, one should test a multivariate regression that incorporates the last week in October change. Then, the numbers themselves will tell the story whether or not trends during that week are useful.

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