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Stratosphere Temperature Watch 2014/2015


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Posted
  • Location: Tilgate, West Sussex
  • Location: Tilgate, West Sussex

    Please notice the difference between CB El Nino and Eastern Based El Nino.

     

    The famous El Nino's of 1982/3 and 1997/1998 were east based El Nino's while 2009/10 was east based El Nino.

     

    Seems to me that El Nino is becoming more Central Based in the coming weeks. We have to wait and see, what happens.

     

    Sorry Sebastiaan so are you saying that all 3 were east based? Or was 09/10 central based? Just that second sentence doesn't sound right :o)

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    Posted
  • Location: New Forest (Western)
  • Weather Preferences: Fascinated by extreme weather. Despise drizzle.
  • Location: New Forest (Western)

    Here's a question for the big-brains on here;

     

    Ex-hurricane Oho is currently on its way to Alaska as what will soon be a powerful ex-tropical system. Next week, another system has the potential to track right up to the high-latitudes as well (again, ex-tropical by that time). Such behaviour was seen last year but before then only once since 1949 (according to Jeff Masters via http://www.wunderground.com/blog/JeffMasters/comment.html?entrynum=3150).

     

    So my question is, what sort of impacts could this have in the troposphere and, more importantly wrt to this thread, could there be effects on the stratosphere as well? Would I be right in thinking that strat. impacts depend largely on whether the relatively warm air associated with the system encounters high land or some other forcing to lift it upward?

     

    Many thanks in advance for your response, I look forward to reading what you have to say  :good:

     

    Apologies for self-quoting but my questions seem to have been overlooked  :ninja:  

     

    If a new thread starts it can be moved over there if you like, mods  :hi:

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    Posted
  • Location: Slovenia, Central Europe 1050m ASL
  • Location: Slovenia, Central Europe 1050m ASL

    QBO well positive, while negative phase lurking above. In the meantime, the polar night jet remains undisturbed mostly. 

     

    u-componentofwindisobari.png

     

    And how do we stack up against last year?

    u-componentofwindisobars.png

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    Posted
  • Location: Manchester
  • Weather Preferences: Sunny and warm in the Summer, cold and snowy in the winter, simples!
  • Location: Manchester

    So you guys can help me out here.

    The PV is modeled to move into Greenland proper but then displace South toward Iceland.My thinking is that this wi;l cause only a temporary strengthening of the jet through Canada/US and across the Atlantic and then in deep FI troughing into Scandinavia a NW/SE aligned jet in the Atlantic.

     

    Am I interpreting the interaction between the PV and potential influence on the jet/upper air patterns correctly or do you have another interpretation I should be aware of?

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    Posted
  • Location: Slovenia, Central Europe 1050m ASL
  • Location: Slovenia, Central Europe 1050m ASL

    Well, I dont have the time for detailed explanations unfortunately, even tho I would love to write it, but instead, i decided to show you how GFS FI looks like in a more realistic way, so you can imagine it. :) basically where and how is the stratospheric vortex connected with the tropospheric one. In the transition zone between 150 to 300mb, the tropospheric effects start to get into play, so the game there is from both sides. but basically looking from 1mb down to 150mb (like where I made this 3D display), you get the clear idea where the main energy goes and where the two entities are connected. :) At least I hope that it gets the message across. :)

    So as you can see, the main tropospheric extension of the strat vortex is actually the double feature, one over Siberia and the other in E'rn Canada. Looks like a "shoe", or where does the P.V. stand in the troposphere. :)

     

     

     

    1.png 2.png 3.png

     

    4.png 5.png 6.png

     

     

    Added jet stream on these two.

    7.png 8.png

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    Posted
  • Location: Manchester
  • Weather Preferences: Sunny and warm in the Summer, cold and snowy in the winter, simples!
  • Location: Manchester

    Well, I dont have the time for detailed explanations unfortunately, even tho I would love to write it, but instead, i decided to show you how GFS FI looks like in a more realistic way, so you can imagine it. :) basically where and how is the stratospheric vortex connected with the tropospheric one. In the transition zone between 150 to 300mb, the tropospheric effects start to get into play, so the game there is from both sides. but basically looking from 1mb down to 150mb (like where I made this 3D display), you get the clear idea where the main energy goes and where the two entities are connected. :) At least I hope that it gets the message across. :)

    So as you can see, the main tropospheric extension of the strat vortex is actually the double feature, one over Siberia and the other in E'rn Canada. Looks like a "shoe", or where does the P.V. stand in the troposphere. :)

     

     

     

    1.png 2.png 3.png

     

     

    Very nice. Much clearer than attempting to interpret from 10hPa strat temp charts.

    So would I infer from that a typical Westerly zonal flow with a flat jet-streak across the Atlantic is modeled for our local - at least in that freeze frame of the GFS 12z Op?

    not withstanding that is how the Jet is modeled for 384h on checking.

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    Posted
  • Location: Slovenia, Central Europe 1050m ASL
  • Location: Slovenia, Central Europe 1050m ASL

    Finally managed to animate my new 3D test matrix for SSW events. In this example is the 2009 SSW event, showing the 150mb geopotential height on the bottom, and the polar vortex in 3D, from 1mb to 150mb, showing the vortex split and complete disintegration of the upper, mid and bottom strat vortex.

    I think it is also appropriate for beginners in this field, to help them understand how an SSW event looks in "real life", since grasping this field from 2D maps alone is not that easy. Or it is at least to show what happens to the strat vortex during the event. If this matrix proves to be stable, I will be able to run it for any SSW you may want to see. 

     

     

    Also going to add the 2009 SSW sequence done in my old matrix. Some improvements are seen in the new matrix above, like a new design, better resolution, new color schemes, and overall a different 3D "engine" than in this older version, for which the matrix I have lost anyway. :D

     

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    Posted
  • Location: Hayward’s Heath - home, Brighton/East Grinstead - work.
  • Weather Preferences: Snow and storms
  • Location: Hayward’s Heath - home, Brighton/East Grinstead - work.

    New paper released this week from Dr Charlton-Perez demonstrating the ability of models to forecast strong and weak vortex conditions

     

    http://iopscience.iop.org/article/10.1088/1748-9326/10/10/104007/meta

     

    Also discussed here

     

    http://www.bbc.co.uk/programmes/p034n5sy

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    Posted
  • Location: Slovenia, Central Europe 1050m ASL
  • Location: Slovenia, Central Europe 1050m ASL

    Speaking of model ability to forecast. The Euro/Atlantic wavebreaking, together with the wave 1 from the Pacific side, will make the first wave2 attack on the polar vortex, though with not much long term damage. but still, its not a bad attempt, and of course gives me the opportunity to quickly model it in 3D, where this is even better shown than on 2D charts.

     

    gfsnh-0-96.png ecmwftz30nhemi229.png nhhgt30mb144.gif

     

     

    You can see how the bottom strat and upper trop is being squeezed in at 300mb where the bottom layer is, with a lagged response to the mid strat. The top layer is at 10mb. I added the 10mb contours at the top to better show what is happening with the mid vortex as a response to lower dynamics. This kind of "trop infused" dynamics are almost standard for the early cold season. Lets not forget the brief low to mid strat split from December 2012. these trop waves are know to sometimes being precursos to more serious events, but we are too soon in the season, and on a bit different configuration than in 2012/2013. What I am trying to say, is that one must not confuse pure direct trop induced dynamics with the dynamics and mechanics of an SSW. Not every wave2 is the same, even if it might briefly look the same on a 10mb 2D chart. Besides, this is not a strong wave2 at all, due to its background, and its much more of a G-wave than a T-wave, which is almost a classic footprint of a brief direct trop induced wave2. 

     

    Anyhow, let the animation roll, and I hope it gets the message across better than my ramblings. :) This is tho nonetheless a good opportunity to test my 3D matrix in an operational forecasting way, to help make certain dynamics more clear and to show a better picture, without having to analyse 200 2D maps. :D at least for me, but thats probably because I kinda got used looking at it while constructing it.

     

     

    Anyhow, the vortex will recover, no sweat, and will avenge to the trop core, sending it somewhere in the Greenland/Atlantic sector, keeping the NAO at least neutral if not positive. 

    kind regards.

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    Posted
  • Location: The Netherlands
  • Location: The Netherlands

    As winter is approaching, the stratospheric polar vortex is taking shape again. Also, there have been some very informative contributions from various posters in here over the past few weeks. One of the key factors mentioned for next winter is that we will have a westerly based QBO (Quasi-Biennial Oscillation). Although this term has been mentioned very often, so far it has left me wondering what it means. Time for some research, I would say :smile:. In this post I will try to find out what the QBO is, and hopefully this also has some uses for some others!

     

    No direct measure about the polar stratosphere?

     

    The first thing that struck me is that the QBO was, contradictory to what I previously thought, not a measure for winds in the polar stratosphere (i.e. the part of the stratosphere located over and near the poles). In fact, the QBO is a measure for the winds in the stratosphere above the equator. To be more precise, it tells something about the zonal winds in the equatorial stratosphere (in other words, whether the winds are blowing from west to east or vice versa)

     

    Order in the atmospheric chaos
     

    Another surprise for me came from the rhythmical behaviour that the QBO possesses. While most oscillations (like the North Atlantic Oscillation) are chaotic and exhibit a chaotic pattern, the pattern of the QBO is actually rather predictable. There is an about 28 monthly cycle incorporated in the QBO, as we will see in a minute.

     

    But first, how is the QBO measured? This is done by taking the zonal mean zonal wind at the equator at 30 hPa height. What does that mean?

    • A zonal mean wind means that the wind is averaged for a complete latitude circle. For example, if you take the zonal mean wind at the equator, you take a sample at every spot at the equator across the globe and take the average of all these wind measurements.
    • Zonal means that you look only at the west-east component of the wind. So you ignore the north-south contributions of the wind.
    • The 30 hPa level is at about 20 kilometres altitude, which is already quite far into the stratosphere

    If you want to know more about the meaning of zonal mean etc., this is a good read: https://en.wikipedia.org/wiki/Zonal_and_meridional

     

    Visualizing the QBO

     

    Below is a plot of the zonal mean zonal wind anomalies (deviations from the mean) at the equator at 30 hPa height.

     

     

    post-20885-0-84539500-1444943785_thumb.p

    Zonal mean zonal wind at the equator at 30 hPa height (red) and 50 hPa height (blue). The x-axis shows the year (96 = 1996 etc.), whereas the y-axis indicates the zonal wind anomaly in meters per second. A positive anomaly indicates stronger westerly winds than average (from west to east) whereas a negative anomaly indicates stronger easterly winds than average (from east to west). Source: NOAA.

     

    We focus only at the 30 hPa line (the red one). From the figure you can see that there is a clear cycle in the zonal mean zonal wind. For example, at the start of 2014, there was a clear positive anomaly, meaning that the zonal mean zonal winds were much stronger from west to east. This is called a westerly based QBO (+QBO).

     

    About a year later (so at the start of 2015), the anomaly flipped sign, and was highly negative. This means that the zonal mean zonal winds were strong easterly. This means that averaged over the equator, the wind blew mainly from east to west. As such, this is named an easterly based QBO (-QBO).

     

    Currently, we are entering a positive phase of the QBO again (a westerly based QBO).

     

    Moving oscillation?

     

    When I tried to visualize the QBO in a different way, I found out that the QBO does not express itself only at 30 hPa, but the ‘waves’ of easterly winds and westerly winds actually descend downward until they reach the troposphere. The cunning reader may have already dissected this from the first figure, as the 50 hPa peaks were slightly delayed compared to the 30 hPa peaks.

     

    But let us zoom in on some individual cases now. First, the westerly based QBO at the start of 2014. We are going to look at the mean zonal wind now. This means the following:

    • We are looking at true zonal wind speeds now, and not at anomalies.
    • The plot below is a so-called cross section. You could see this as if we make a slice through the atmosphere at the equator. We look at each individual point at the equator between 10 and 100 hPa height (that is, in the stratosphere). But we do not average the wind to obtain only one value.

     

    post-20885-0-01306100-1444943733_thumb.p

    Zonal wind averaged over January 2014 between 10 and 100 hPa height at the equator. Red colours indicate west-to-east blowing winds, whereas blue winds indicate the opposite. The black line indicates the level at which the QBO is defined. Source: NOAA.

     

    What we can see is that during January 2014, winds were blowing vigorously from west to east at about 15 meters per second (50 km/h). This is also shown by the red circle. However, what is also visible is that at the top of the stratosphere, near 10 hPa, winds were blowing from east to west (blue circle).

     

    Downward propagation

     

    The wind signatures that we see above tend to propagate downward towards the bottom of the stratosphere, where they dissipate. So the easterly winds we can observe at the top of the stratosphere would descend downward slowly and reach the level of 30 hPa in about a year. This becomes totally clear when we take a look at what happened exactly a year later.

     

    post-20885-0-79974900-1444943737_thumb.p

    Zonal wind averaged over January 2015 between 10 and 100 hPa height at the equator. Red colours indicate west-to-east blowing winds, whereas blue winds indicate the opposite. The black line indicates the level at which the QBO is defined. Source: NOAA.

     

    The winds at January 2015 have reversed completely as compared to a year before! In fact, strong easterlies now blow at 30 hPa throughout the equatorial longitude. The easterlies we saw at the top of the stratosphere have descended all the way down to the 30 hPa level (blue colour; an easterly based QBO).

     

    Of course this cycle continues, and we can see the new westerlies emerging at the top of the stratosphere, which is indicated by the red circle.

     

    This whole process is visualized much more clearly by a video of Mark Baldwin: http://people.nwra.com/resumes/baldwin/.

     

    Summary
     

    What started with a small search about an oscillation in the stratosphere has resulted for me in some fascinating new insights about what the QBO is and that this oscillation is actually fairly regular. Of course many questions yet remain unanswered in this post (like what the effect of the QBO is on the stratospheric polar vortex in winter and what the physical basis is of the QBO). However, knowing what the QBO is, is essential for acquiring a good background to continue exploring the topic, reading papers and many more! And that is definitely what I am going to do :smile: . Hopefully this post has also been clarifying for some of you as well! If you have any contributions, remarks or anything else, please do not hesitate to add them!

     

    Sources and further exploration

     

    Below I will list the sources I consulted for my exploration of the QBO, and give some explanation if you are interested to explore the QBO even more.

     

    https://www.meted.ucar.edu/index.php = a great site containing lots of information and tutorials about meteorology. Though it does require a signup, the wealth of information available (also about the QBO) is very valuable.

     

    https://forum.netweather.tv/topic/81567-stratosphere-temperature-watch-20142015/ = the explanation by Chionomaniac about the stratospheric conditions of last year.

     

    https://en.wikipedia.org/wiki/Quasi-biennial_oscillation = a good place to start exploring the QBO. There are some links to very interesting papers in there.

     

    http://www.esrl.noaa.gov/psd/cgi-bin/data/composites/printpage.pl = the site I used to create the anomaly plots. Fun to explore in yourself.

     

    http://www.cpc.ncep.noaa.gov/data/indices/ = the site I obtained the first figure from.

     

    http://people.nwra.com/resumes/baldwin/ = containing a very clarifying image about the QBO. Worth to watch.

     

    https://en.wikipedia.org/wiki/Zonal_and_meridional

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    Posted
  • Location: just south of Doncaster, Sth Yorks
  • Location: just south of Doncaster, Sth Yorks

    As winter is approaching, the stratospheric polar vortex is taking shape again. Also, there have been some very informative contributions from various posters in here over the past few weeks. One of the key factors mentioned for next winter is that we will have a westerly based QBO (Quasi-Biennial Oscillation). Although this term has been mentioned very often, so far it has left me wondering what it means. Time for some research, I would say :smile:.

     

    as always V a first class and objective post from you-thank you

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    Posted
  • Location: Slovenia, Central Europe 1050m ASL
  • Location: Slovenia, Central Europe 1050m ASL

    Cool to have this QBO explanation. It was explained many times, but always piece by piece, or just mentioned. :)

     

    The best way to look at the QBO is through a latitude cross section on a zonal mean. There you can get the best feeling where its at and how strong. I am not a fan of using zonal wind anomalies for assessing the QBO, since it is already a bi-polar feature by nature. 

     

    So here is an example of a zonal mean from GFS analysis and forecast, where you can see both phases of QBO. :) The best way to look at QBO is on a logarithmic vertical scale. 

     

    u-componentofwindisobari.png u-componentofwindisobari.png u-componentofwindisodbar.png

     

    And analysis focused on the QBO region, and a longitude cross section, like you did with ESRL plots. :)

     

    u-componentofwindisodbri.png u-componentofwindisobari.png

     

    @knocker: Not sure exactly, since I hardly read any papers since 2011, but I do remember someone finding some additional features via solar cycle among other stuff, and the BDC stratosphere connection, since the QBO could connect to the troposphere also by the stratospheric and SSW dynamics. Kinda like a backdoor entrance to the troposphere. But there is more to this than just the polar vortex in this case. :)  

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    Posted
  • Location: Camborne
  • Location: Camborne

    In a book I have, Stratosphere Troposphere Interactions By K. Mohanakumar he states that though the equatorial phenomenon is well understood the problem of how the equatorially confined QBO forcing can induce a signal in the troposphere and also to the extratropics of comparable or even larger amplitudes remains unsolved. Has this been resolved since the publication which was 2008?

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    Posted
  • Location: The Netherlands
  • Location: The Netherlands

    Cool to have this QBO explanation. It was explained many times, but always piece by piece, or just mentioned. :)

     

    The best way to look at the QBO is through a latitude cross section on a zonal mean. There you can get the best feeling where its at and how strong. I am not a fan of using zonal wind anomalies for assessing the QBO, since it is already a bi-polar feature by nature. 

     

    Great suggestion Recretos! Indeed the latitude cross section images allow you to tell much more than only the QBO, and also allow to put the QBO into perspective (basically it shows what a small-scale feature it is compared with everything that is going on :D ).

     

    Though I agree that a logarithmic view is indeed a better approach, with the limited capacity of the ESRL plots (and lack of programming skills) I am unable to create such a scale yet. However, fortunately it is possible to create latitude cross section images with the ESRL tool. So I will update my QBO post tomorrow with some extra latitude cross section plots as an extra clarification!

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    Posted
  • Location: Slovenia, Central Europe 1050m ASL
  • Location: Slovenia, Central Europe 1050m ASL

     

    Though I agree that a logarithmic view is indeed a better approach, with the limited capacity of the ESRL plots...

     

    Oh the good old days, of being limited to the ESRL and online plotting. :) I know exactly where you come from, dont worry. :) I was just trying to add generally for all the rest, that he best way to look at the QBO is also as a zonal mean zonal wind on a latitude cross section. i was not trying to say that your plots are not right or anything. God forbid. Keep up the good work. :)

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    Posted
  • Location: Manchester Deansgate.
  • Weather Preferences: Heavy disruptive snowfall.
  • Location: Manchester Deansgate.

     

     

    With a 14-21 day lag applied, planetary wave activity over the Pacific low should allow for some moderate Wave 1 activity displacing the upper vortex towards Siberia and Wave 2 activity following end of the month into November. All in all, reasons to think that the stratospheric vortex will be on the weak and slightly displaced end of the spectrum come November.

     

     

     

     

    Early tentative signs perhaps?

     

    gfsnh-10-372_etf6.png

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    Posted
  • Location: Worcestershire
  • Weather Preferences: Forecaster Centaurea Weather
  • Location: Worcestershire

    Looks more impressive as an anomaly at this stage. Only picked up by the GFS op at this stage on an inconsistent basis.

     

    EC EPS continues with a warm theme across much of the NH, and tentatively suggests some warmth over the Canadian sector and cooling over Eurasia.

     

    Northern hemisphere profile around 26th October also looks good for Wave 1 & 2 activity to be a player again, particularly with a big MJO wave in play over the Indian Ocean although that might have more relevance for early / mid November.

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    Posted
  • Location: Hayward’s Heath - home, Brighton/East Grinstead - work.
  • Weather Preferences: Snow and storms
  • Location: Hayward’s Heath - home, Brighton/East Grinstead - work.

    Hopefully I will have a new thread up and running at some point this weekend, then we can start discussing this winter in the appropriate thread.

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    Posted
  • Location: The Netherlands
  • Location: The Netherlands

    In my previous post I did some analysis about what the QBO is, and how it can be visualized. Based on helpful advice of Recretos, here I will extend the visualization of the QBO to a new level, which makes it easier to put the ‘size’ of the QBO into perspective. Hopefully this part will be a positive addition to the previous post!

     

    A latitude cross section on a zonal mean… what?

     

    The way I will plot the QBO now, is via a latitude cross section on a zonal mean of the zonal wind. Now you might think: what does that mean? Therefore, we will first go into detail about the way of plotting mentioned here, treating every word group piece by piece.

    • A latitude cross section means that you cut through the Earth from pole to pole. In that way you obtain a ‘slice’ of the Earth from pole to pole. This is exactly the other way around compared to a longitude cross section.
    • A zonal mean wind means that the wind is averaged for a complete latitude circle. For example, if you take the zonal mean wind at the equator, you take a sample at every spot at the equator across the globe and take the average of all these wind measurements.
    • Zonal wind means that you look only at the west-east component of the wind. So you ignore the north-south contributions of the wind.
    • Combining the pieces above results in the definition of a latitude cross section on a zonal mean of the zonal wind: “you obtain a ‘slice’ of the Earth from pole to pole, where each point at a given latitude contains the average zonal (west-to-east oriented) value of the wind speed of all points at that latitude circle at a given heightâ€.

    Describing the latitude cross section on a zonal mean of the zonal wind is, as you can see above, quite a challenge, but I hope this explanation is reasonably clarifying!

     

    The west-based QBO of the start 2014

     

    Here we are going to take a look at the west-based QBO of the start of 2014 (the image will be from January). Refer to my previous post if it is unclear what a west-based QBO (W-QBO) is.

     

    post-20885-0-51252100-1445078366_thumb.p

    Latitude cross section on a zonal mean of the zonal wind over January 2014 between 10 and 100 hPa height (roughly the level of the stratosphere) at the equator. The x-axis indicates the latitude, whereas the y-axis indicates the height in hPa. Red colours indicate west-to-east blowing winds, whereas blue winds indicate the opposite. The black cross indicates the “level†at which the QBO is defined. Source: NOAA.

     

    Let us first focus on the QBO itself. We can see that at the black cross, the winds are weak westerly, indicative of a westerly based QBO (encircled in red). Just look how small this area is! Yet, such small area of westerly winds does have effects on the stratospheric polar vortex, as mentioned some times in literature.

     

    On top of the W-QBO area, we see another area of strong easterly winds developing (at about 10 hPa, indicated by the blue circle). This area will propagate downward to about 30 hPa in about a year, and change the W-QBO into an easterly based QBO (E-QBO), as mentioned in my previous post.

     

    Polar vortex visible?

     

    On the image above, we can actually identify the polar vortex! The image is taken in January 2014, meaning it was winter on the Northern Hemisphere, and summer on the Southern Hemisphere. The polar vortex shows up nicely with an area of pretty strong westerly winds (west to east blowing winds) at about 60 North (indicated by the black rectangle).

     

    You can view the westerly winds at 60 hPa as the ‘edge’ of the polar vortex itself. As you creep closer to the polar vortex (so closer to 90N), the winds become weaker again because the pressure gradient is smaller there.

     

    The easterly based QBO of the start of 2015

     

    As with the 2014 case, but now we are going to face an easterly based QBO!

     

    post-20885-0-53197500-1445078389_thumb.p

    Latitude cross section on a zonal mean of the zonal wind over January 2015 between 10 and 100 hPa height (roughly the level of the stratosphere) at the equator. The x-axis indicates the latitude, whereas the y-axis indicates the height in hPa. Red colours indicate west-to-east blowing winds, whereas blue winds indicate the opposite. The black cross indicates the “level†at which the QBO is defined. Source: NOAA.

     

    The easterly based QBO shows up very nicely with strong easterly winds near the equator, 30 hPa (purple colours, encircled with blue). Note that the easterly winds are much stronger than the westerly winds we saw in January 2014 associated with the W-QBO. The area of easterly winds near the Equator appears to be significantly larger as well.

     

    If you look very carefully, you can see the next westerly phase of the QBO already emerging at the top of the stratosphere (near 10 hPa, encircled in red).

     

    A stronger polar vortex than in 2015?

     

    Once again remember that the image above is taken in the Northern Half Winter. If we compare the area where the polar vortex resides, we can see once again that there are strong westerly winds blowing near 60N (red rectangle). Although the colours are darker than in 2014, this is due to a difference in scale. In fact, the polar vortex in January 2014 appeared to be stronger than the one in January 2015, judging from the strength of the westerly winds near 60N.

     

    Concluding note

     

    Hopefully the explanation given above adds up to the explanation I gave before on the QBO. As Recretos correctly suggested, much more can be visualized with such a plot, like the polar vortex. This is what I also identified when writing this part. For example, I have not even commented on what was happening in the Southern Hemisphere, while much can be seen there as well! It would be great if you could provide some feedback or suggestions, these are more than welcome!

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