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SSW Event Was Widely Forecast In Early Feb

March 19, 2018

By Paul Homewood

 

It has been suggested that the Sudden Stratospheric Warming event in the middle of last month was not widely forecast well beforehand, and that somehow only the Met Office knew about it.

In fact, this is bunkum, as amateur weather blogger Mark Vogan discussed on 5th February:

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Whether you love weather, cold weather or both, we all get excited at the thought of a sudden stratospheric warming event. No question it’s a truly spectacular event and awesome to watch on the many incredible graphics we have at our finger tips these days.

While they only occur every so many years, there is a problem when they do occur with either the collapse of the entire polar vortex or split. Either way we know it’s effects often lead to extreme cold winter weather for a prolonged period within the mid latitudes. But where do those cold pools go? The upcoming SSWE which is seen by the models may see a piece of the vortex drop into Western Europe bringing us bitter cold during the later of February and much of March OR could go into eastern Europe with mild blocking high pressure leaving the UK disappointed.

While the SSWE looks likely, the models still have differing opinion on where the cold pool sets up. For example the first below chart doesn’t look good for cold weather lovers in the UK and west of Europe.

However, this does!

Latest tweets on the forecasted SSWE.

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Mark’s blog includes more such tweets here.

 

So it is clear that there was evidence of the SSW forming as early as 3rd Feb, two days before the Met Office first appeared to go public.

As Mark Vogan explained, there was still a lot of uncertainty of just where the cold weather would impact, as is always the case in these matters.

Indeed, even by 9th Feb, Matthew Lewis, Deputy Chief Operational Meteorologist at the Met Office, was still uncertain:

A Sudden Stratospheric Warming event is now expected to occur and will peak over the coming week. The resulting impact on the weather in the UK is still hugely uncertain, but there are some signs of conditions that an easterly flow could develop across Europe. Although we wouldn’t expect continuously cold conditions there is a greater chance of cold conditions recurring.”

https://www.metoffice.gov.uk/news/releases/2018/how-long-will-the-cold-conditions-remain

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20 Comments
  1. Broadlands permalink
    March 19, 2018 6:58 pm

    Paul had earlier noted the “expert” real reason? Our addition of CO2 from burning stuff.

    “Overpeck’s theory is that a loss of Arctic ice has allowed more heat to transfer from the ocean to the atmosphere, causing a weakening of the polar vortex winds over the Arctic. As a result, more freezing Arctic air is swooping further south, he proposes.
    “That is due to the warming of the Arctic, which in turn is due to human emissions of greenhouse gases and primarily burning of fossil fuels,” Overpeck declared.”

    • Bitter@twisted permalink
      March 19, 2018 11:16 pm

      Overpeck is overrated.
      He is a climatastrologist with a dodgy glass ball.
      Delusional idiot thinks he can predict the future.
      Says it all.

  2. tom0mason permalink
    March 19, 2018 6:59 pm

    Real meteorologists looks at past events to inform them about future probabilities. The Met Office has trash that idea by relying on computer model to inform them about possible future outcomes.
    And that is their (the Met Offices) stupidity, (IMO) for to this idea to be a worthy method they must show that computer models can calculate how our dynamically chaotic weather system functions. Computer model’s can not do this task, and now they are left with egg on their faces, as the real (and even talented amateur meteorologists like Gavin at https://www.youtube.com/watch?v=_GOYTduIKZM )saw this SSW event evolving and reasonably accurately forecast the outcome from it.

    • Sheri permalink
      March 19, 2018 8:01 pm

      Our weatherman shows us the US and the European models, which often differ. That should be a clue that weather forecasting via models is at best a developing science. Even use of past to predict future is a shakey task. Prediction is mostly art, not much science, much to the chagrine of many.

    • Phoenix44 permalink
      March 20, 2018 9:06 am

      One of the unacknowledged problems with all models of complex, dynamic, non-linear systems is getting the starting conditions of your model right. It is a say to send a rocket to Mars because you know where everything is and what is doing, but that can never be true for the climate (or the economy). And if you can’t get the starting position right, you cannot get the forecast right – and in a semi-chaotic system, small errors can lead to huge errors.

  3. mikewaite permalink
    March 19, 2018 8:23 pm

    One of the odd aspects of the recent weeks was the apparent inconsistency of the advice from A Scaife one of the top Met Office Forecasters . Judging from his research as shown by papers in Google Scholar he appears to be a very good scientist, and has specialised in NAO influence on Northern Europe (obviously, being a UK civil servant) trying amongst other work, to link extreme cold weather events to different factors , including the old favourite of solar variability.
    A paper 5 years ago , looking back at the cold winter of 2009/10 seemed to suggest that they had a better understanding of the effect of stratospheric events on extreme cold in north and eastern europe:

    -“Seasonal forecasts of northern hemisphere winter 2009/10
    D R Fereday, A Maidens, A Arribas, A A Scaife and J R Knight
    Published 13 September 2012 • 2012 IOP Publishing Ltd
    Environmental Research Letters, Volume 7, Number 3

    Abstract

    Northern hemisphere winter 2009/10 was exceptional for atmospheric circulation: the North Atlantic Oscillation (NAO) index was the lowest on record for over a century. This contributed to cold conditions over large areas of Eurasia and North America. Here we use two versions of the Met Office GloSea4 seasonal forecast system to investigate the predictability of this exceptional winter. The first is the then operational version of GloSea4, which uses a low top model and successfully predicted a negative NAO in forecasts produced in September, October and November 2009. The second uses a new high top model, which better simulates sudden stratospheric warmings (SSWs). This is particularly relevant for 2009/10 due to its unusual combination of a strong El Niño and an easterly quasi-biennial oscillation (QBO) phase, favouring SSW development. SSWs are shown to play an influential role in surface conditions, producing a stronger sea level pressure signal and improving predictions of the 2009/10 winter”-

    http://iopscience.iop.org/article/10.1088/1748-9326/7/3/034031/meta

    (open access)

    My suspicious mind makes me wonder whether Scaife and his team knew early in the year what was going to happen in Feb , but were constrained by the higher management’s previous insistence on a milder than average winter, as dictated by the global warming doctrine.
    If so , I imagine that Dr Scaife is a bit annoyed , to put it mildly.

  4. March 19, 2018 8:31 pm

    As noted before, Dr. Judah Cohen of AER was anticipating the stratospheric disruption already in October due to extensive Siberian snow cover. His forecasting paradigm is conveyed by this image:

    More explanation at https://rclutz.wordpress.com/2017/10/24/snowing-and-freezing-in-the-arctic/

  5. Coeur de Lion permalink
    March 19, 2018 10:47 pm

    Overpeck is credited with the “we must do away with the MWP” on the Climategate emails catastrophe

    • dave permalink
      March 20, 2018 8:35 am

      Whatever…normal service has been resumed, up there:

      http://ocean.dmi.dk/arctic/meant80n.uk.php

      • dave permalink
        March 21, 2018 9:21 am

        The theory that the Arctic is warming in winter simply because there is a greater flux of heat from the ocean into the atmosphere, as a result of reduced sea-ice-cover, is – quantitatively speaking – rubbish.

        Without going into the justification, it can be stated that the upward flux in winter from open-water in the marginal seas as compared to ice-covered water, is of the order of 20 W/M^2. We are talking about a possible million square kilometers of reduced ice cover in a region of at least 20 million square kilometers. That is equivalent to 1 W/M^2 for the Arctic region.

        The atmosphere in the Arctic continuously radiates to space at roughly 160 W/M^2.

        By the 4th order law, the Arctic atmosphere would need to increase in temperature by about 1/2 Degree C, to shed the extra heat and dynamically re-balance itself.

        Typical atmospheric temperatures in the Arctic drop 30 degrees C every winter! The occasional excursions upwards are 10 to 20 C.

        The comparisons are simply absurd.

    • March 20, 2018 9:18 am

      I know somebody who knows Overpeck (slightly). To be fair (must I?) there is at least a suggestion that that remark was misunderstood.

      One of the dangers of “eavesdropping” on people’s emails is that how they communicate within a community is not always understood by outsiders. Like jargon.

      It is as likely, I am told, that the “full” message, as opposed to the written word was “if you want to go down that route (which is essentially the route that *some* — notably Jones and Mann — did want to go down) then you would need to get rid of the MWP.”

      Plausible. But then again … Who knows?

  6. March 20, 2018 8:50 am

    I’m a member of an amateur weather forum and there was plenty of excitement about the SSW many weeks before the Met Office went public with it.

    I believe there has actually been three SSW’s, approx 10 days apart and with decreasing intensity, the UK experiencing cold easterly winds approx 10 days after each SSW

    I, along with others, posted comments about it in other forums. In one case I was branded an idiot by a farmer who informed me that he had a ‘proper’ long range forecast from MO that showed warmer than average conditions and no significant risk of frost for March.

    Many amateurs also predicted Beast2 far sooner than MO and are now suggesting that there could be a mini Beast3 at Easter.

    There are dozens of weather models used by amateur forecasters but the GFS seemed to detect the potential impact of the SSW’s earlier and more accurately than the MO, ECM etc.

    To be fair though, MO models were showing potential Beast conditions over a week before they went public with it and the BBC failed to warn about the cold until it was virtually on us. I assume because they are too worried about calling it wrong and looking foolish. After all, the UK is a tiny island in global weather terms. It only takes a small shift of a few hundred miles to make the difference between the weather systems hitting us or missing us. Quite often the models can’t get accuracy to within 100 miles until less than 72 hours out.

    • March 20, 2018 8:55 am

      Well Mud, I hope you have recently been in contact with the farmer who branded you an idiot.

    • Phoenix44 permalink
      March 20, 2018 9:01 am

      If you run lots of models that all produce different outputs, one is reasonably likely to be right. Only if it’s the same one each time is it any good though!

      • March 20, 2018 9:20 am

        True.

        The GFS model has shown consistently for a week now that a cold easterly could happen at Easter with potential for snow. However it is not supported by other models yet. I believe (last time I checked) that MO model is predicting a warm and wet south westerly (which would be more usual for UK).

      • March 20, 2018 9:38 am

        Sorry that should be GFS predicting cold north/north easterly at Easter, not easterly.

  7. Brett Keane permalink
    March 23, 2018 11:48 pm

    What does this mean for the idea that SSWs can happen from solar eruptive sources (eg Ren)?
    Joe Bastardi seems to be getting good results by adding previous historical data matchups to his techniques……

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