QBO

[Glacier Point]

http://en.wikipedia.org/wiki/Quasi-biennial_oscillation

http://ingrid.ldeo.columbia.edu/maproom/.G...lation/QBO.html

http://www.cdc.noaa.gov/Correlation/qbo.data

Before I go any further, the Quasi Biennial Oscillation (QBO) is NOT a key determinant on our weather patterns on its own. It is perhaps one of several climatic variables, which, once they align, are likely to act as one super teleconnection.

In laymans terms, the QBO is the directional flow of upper level winds on the edge of the atmosphere across the equator. These flow either westerly or easterly on a 9-18 month cycle.

Currently we are in an easterly cycle - which is governed by the solar flux. It is arguably an important phenomenon as it is know to affect the distribution of ozone and water vapour in the stratosphere and is linked to disruption of the winter time polar vortex during easterly phases.

Last winter, during the westerly phase, we observed a very strong polar vortex which refused to break up until April demonstrating the importance of the upper level wind flows supported by the QBO. It also underlined the statistic that there had never been an early final break up of the polar vortex during a westerly phase QBO at the bottom of the solar minima.

Right now, we see a possible record strength easterly phase QBO developing. Comparison of similar easterly phases places us on course to break the record set in 2005, possibly as early as this month although I would favour either October or November if we are to do it:

Analysis of upper level zonal wind flow shows that the strength of the easterly QBO has, if anything, intensified during the first few days of September.

Why is this important ? Well, for one thing we know pretty much where the QBO will be come late November, which will be of great assistance to those of us putting a winter forecast together.

Also, the QBO is potentially related to the development of easterly upper zonal winds over the polar region during the winter months which assists high latitude blocking to develop. Reanalysis of strong easterly (-ve) QBO events during the northern hemisphere winter confirms the relationship between QBO and height rises over Greenland and lower pressure over the mid Atlantic consistent with a neg AO NAO regime (remember for linear correlations with the -ve QBO you need to reverse the anomaly).

What's also interesting there is that the QBO looks to have a relationship with the high pressure cells over the Pacific and Atlantic (more so the Atlantic).

With a record QBO in the offing just before winter, we have some support for a winter comparable to that of 2005/6 based on the QBO alone with plenty of blocking. I stress again though, the QBO on its own is not a forecasting tool. There are plenty of examples where the QBO was negative but where the winter was not cold. What does interest me is its relationship with the Arctic Oscillation and El Nino Southern Oscillation, possibly providing a link between the two.

Despite all this, having the QBO on your side cannot be a bad thing if you'e looking for a blocked winter.

[The PIT]

Interesting although the Winter of 2005/6 wasn't particularly noteworthy compared to winters off old it may provide us with a few talking points.

So far your Autumn prediction is going fairly well bar the warmth.

[Glacier Point]

2005/6 is as good an analogue for QBO as you are going to get.

Given what we think the QBO might mean in terms of high latitude blocking, it was disappointing that 2005/6 turned out be not as cold as it could have been (although for central and eastern Europe it was a different matter). I would regard this as a near miss, possibly due to all that huge ridge over Scandinavia that persisted for most of the Autumn - one reason why we must see that upper trough persist in this locale this Autumn.

[summer blizzard]

Great Post Glacier Point...

In regards to the QBO peak, i disagree, i believe that we will fall short of the record peaking this month before a slow rise...

I also believe that your anologues are outdated, the best duo-monthly anolgues are:

2005

2003

1998

1996

1984

In regards to the coming winter, the QBO state has a 0.3 positive correlation with the AO, so a early southward displaced Polar Votex could be in the offing.

In regards to El Nino, there is a 0.6 positive correlation however there is a lag time of 6-8 months, meaning that in 6-8 months time we should be seeing ENSO index peaking assuming the QBO peak occurs now.

Glacier Point, do you have the link to the QBO data in standard deviation, not raw values??

[The PIT]

As ever how good your prediction is in the realms of the future can only be judged in spring. All the best.

[Glacier Point]

As ever how good your prediction is in the realms of the future can only be judged in spring. All the best.

Just to make this clear. There is no forecast which can be based on QBO alone. That will have to wait to late November and, in particular, how the polar height anomalies look...

[Mark Bayley]

Interesting read

[Gavin P]

Thankis GP

On slightly matters, I've been looking at that huge area of missing ice on the middle of the arctic and wondering what effect it'll have? I'm thinking we can expect some deep storms across the area of Eastern Siberia and Western Cananda and this may force higher pressure through Greenland and Eastern Canada?

[mezzacyclone]

sorry to temporary deflect the topic for a moment and address something concerning one of the other 'players' but,,,,,

wasn't 05-06 winter the one where the sustained extreme cold pool built up over the continent and the one that we just failed to tap into?

I assume this Summary is correct/accurate in that 05-06 was the lowest -NAO since 95-96?

Reason for this little ditty is that I cant seem to find anything of value in regards to historic QBO values and the effect (if any) it had on winters passed?

Perhaps im still suffering from a lapse following Steve M's legendary NW post ?

well its that or the warsteiner beer?

[Glacier Point]

Thankis GP

On slightly matters, I've been looking at that huge area of missing ice on the middle of the arctic and wondering what effect it'll have? I'm thinking we can expect some deep storms across the area of Eastern Siberia and Western Cananda and this may force higher pressure through Greenland and Eastern Canada?

I would have thought that was a reasonable assumption, not least be because the areas of much warmed sea will be very late to freeze over, supplying plenty of moisture for rapid build up of snows eleswhere over the polar region, in turn leading to ozone production and stratospheric warmings (a possible link to the QBO and this 'super teleconnection I discussed). It could on the other hand fuel another strong polar vortex and months of mild misery. The bottom line is that we simply don't know how this huge polar anomaly will impact on winter weather patterns across the NH although I fancy that the impact will along the lines discussed in the AO thread.

Mezza:

The direct impacts of the QBO are more evident in the upper stratosphere so it's difficult to tie down impacts at surface level. The best lead comes from the reanalysis of strong QBO winters:

which actually validates the theory that when all these things are aligned, in this case NAO/QBO/AO, some serious anomalies, even in the modern context, can and will occur (although not of the same histoic scale to say the 1960s)

[Gavin P]

Thanks again GP.

I'll check the other thread out.

[Bobby]

Very interesting. A few positive signs seem to be emerging regarding the winter, while hardly a guarantee of a cold one, can only be a good thing.

[Snowyowl9]

2005/6 is as good an analogue for QBO as you are going to get.

Given what we think the QBO might mean in terms of high latitude blocking, it was disappointing that 2005/6 turned out be not as cold as it could have been (although for central and eastern Europe it was a different matter). I would regard this as a near miss, possibly due to all that huge ridge over Scandinavia that persisted for most of the Autumn - one reason why we must see that upper trough persist in this locale this Autumn.

A very dry colder winter 2005/06 was and it`ll be interesting if it happens again.

Just a few very blocked charts from that late autumn/winter each month which were very chilly to recent years.

http://www.wetterzentrale.de/archive/ra/20...00120051118.gif

http://www.wetterzentrale.de/archive/ra/20...00120051228.gif

http://www.wetterzentrale.de/archive/ra/20...00120060126.gif

http://www.wetterzentrale.de/archive/ra/20...00120060201.gif

This just looks like a normal chart just above but it never got above -1.1c that day.

http://www.wetterzentrale.de/archive/ra/20...00120060303.gif

[Optimus Prime]

The best chart of recent years, SO9 was March 2005;

We came so close to something very notable for March.

Of course March 2006 was exceptional. First half with an average temperature of 3.0c withg some notable snowfalls and low temperatures;

What about this for a late March chart! 25c has been recorded as this point in history;

Looks like this coming winter could have some interest.

[Snowyowl9]

The best chart of recent years, SO9 was March 2005;

It was a great March there`s not doubt about it best for cold/snow for a good number of years.

Coldest night/day however during the whole winter was this day...

http://www.wetterzentrale.de/archive/ra/20...00120051229.gif

As it got down to -8.2c with a max of -2c(-9c min and -3.5c max on the old mercury one) making it the coldest night/day since not 1996 very close mind but...

When -5c was the max and -9c the min and what`s uncanny is it`s exactly 10 years to the day.

[Snowyowl9]

Coldest night/day however during the whole winter was this day...

http://www.wetterzentrale.de/archive/ra/20...00120051229.gif

As it got down to -8.2c with a max of -2c(-9c min and -3.5c max on the old mercury one)

Since I started recording temps in Jan 1990 just checked back and I make that the the 5th coldest night/daytime temps which is impressive.

And I remember that day very well too it felt perishing with a slight SE breeze.

[Glacier Point]

Current anomalies keep us on track to possibly take the record this month with generally -25 m/s anomalies showing up quite widely and I suspect a few -28s in there too.

What really takes the eye is what's going on in the southern hemisphere where the upper zonal wind anomaly is showing a perfectly symetrical wave pattern. Very pretty !

[summer blizzard]

Glacier Point, we hit -29 in October, so should probably take the record if the peak occurs during November, but could you update us as to whether the peak has occured already or whether we will see the record go??