Snow in Tokyo

[Martin Rowley [West Moors/East Dorset]]

... I've been holding off mentioning this, because I thought it would have created a flurry of posts pointing out the possible portents of 'things to come'!

This page here . . . www.bbc.co.uk/news/world-asia-38089174 . . . is a good summary of most of the news reports from last Thursday: JMA apparently are quoted as saying that " The frigid air, otherwise kept locked in the polar region, has been released in the current phase of "Arctic Oscillation" (etc.).

We all know what happened in /our/ winter 1962/63: anyone with access to more data know if the broad-scale patterns were similar to current patterns, back in 1962?

Martin.

[Smartie]

Greatbatch et al-Tropical origin of the severe European winter of 1962/1963

http://onlinelibrary.wiley.com/doi/10.1002/qj.2346/abstract

Find a number of large scale anomalies-

A set of relaxation experiments using the European Centre for Medium-Range Weather Forecasts (ECMWF) atmospheric model is used to analyze the severe European winter of 1962/1963. We argue that the severe winter weather was associated with a wave train that originated in the tropical Pacific sector (where weak La Niña conditions were present) and was redirected towards Europe, a process we suggest was influenced by the combined effect of the strong easterly phase of the Quasi-Biennial Oscillation (QBO) and unusually strong easterly winds in the upper equatorial troposphere that winter. A weak tendency towards negative North Atlantic Oscillation (NAO) conditions in December, associated with extratropical sea-surface temperature and sea-ice anomalies, might have acted as a favourable preconditioning. The redirection of the wave train towards Europe culminated in the stratospheric sudden warming at the end of January 1963. We argue that in February the sudden warming event helped maintain the negative NAO regime, allowing the severe weather to persist for a further month. A possible influence from the Madden–Julian Oscillation, as well as a role for internal atmospheric variability, is noted.

Also 62/63 was in the downward trend of a sunspot cycle nearing the nadir, as we are now. Major differences are that the QBO should be westerly this winter  and the warm arctic and low sea ice. However, low sea ice in the Barents-Kara Sea is thought to favour a weak AO, ie. a weak polar vortex so at least some of the 'pre-conditioning' may be in place. Greatbatch et al note

It seems likely that extreme winters such as 1962/1963 probably occur

when both a forced response, e.g. from the Tropics, and internal

variability happen to interfere constructively.

I suggest that the current quasi-stationary wave pattern we've seen in the past months with high amplitude ridge-trough system in the east Atlantic  may be due to Rossby wave forcing from the tropics (weak La Nina). It  will be interesting to see what the effects of a major SSW are when (if) it happens given a  'pre-conditioned ' state, although the climate background state has changed substantially since the early '60s. One of the things about 62/63 is the longevity of the cold and the current outlooks are not going for a cold second half of the winter, but that could hinge on a new year SSW.

[Martin Rowley [West Moors/East Dorset]]

... Thanks very much for that analysis: as you point out, the climatological regime (in terms of, for example, mean surface temperature) is quite different today: for example, the 10-year mean CET for December 1960-1969 = 3.48, significantly below the decades before and after [for comparison mean December CET  2000-2009 = 4.77, mean for 2010-2015 (6yrs) = 5.22, and that includes the notable December 2010 event of course].

One thing is clear: should this winter turn out to be 'interesting', the methods by which we can monitor the atmosphere-ocean-ice-sun system(s) is vastly improved on those which were available in 1962!

Martin.

[Richard Dixon]

On Wednesday, 30 November 2016 09:56:47 UTC, Martin Rowley [West Moors/East Dorset] wrote:

One thing is clear: should this winter turn out to be 'interesting', the methods by which we can monitor the atmosphere-ocean-ice-sun system(s) is vastly improved on those which were available in 1962!

It's interesting if you look at the Autumn QBO in the run-up to winter how 1962 sat in the grand scheme of things: negative, but not remarkably so - can also see how this winter is positive, AND it's also the first winter where we've had a positive QBO also in the previous winter in the modern QBO record since 1948...

Also useful to see what impact the Autumn QBO going into winter has when plotted against the winter (UK) CET:

Not much notable correlation really - at least to the eye. Which if anything underscores the idea that a number of things have to come together to create the right conditions for a cold winter and we can't rely on a single index. But this is not new - just did this for my own curiosity.

Richard

[Smartie]

Rich - could you plot similar for DJF QBO please?

[Graham Easterling]

Also, the N Atlantic SSTs are very, very different to 1962/63. Still over 12C in parts of the Bristol & western English channel currently. In fact even the cold (relative to recent years) pool, has largely gone now http://polar.ncep.noaa.gov/sst/rtg_low_res/global_anomaly_oper0.png Not much chance of sea ice off Essex this year.

Despite the easterly, a maximum of 10.7C in Penzance today, after the coldest night so far this autumn (by a full 3C) with a minimum of 0.1C

Weather's always interesting & throws up surprises. I'd hate for forecasts to be too accurate, and fortunately there's little sign of that for quite while.

Graham

Penzance

[Richard Dixon]

On Wednesday, 30 November 2016 13:25:18 UTC, Smartie wrote:

Rich - could you plot similar for DJF QBO please?

Will do.

Bit of reasoning behind the previous charts I did was basically around the question "can we use the existing/Autumn QBO state to help guide thoughts on the forthcoming winter..." - the result didn't surprised me in the slightest given small gains are the way forward in seasonal forecasting rather than any one magic bullet.

Richard

[Smartie]

Cohen links this paper from his blog

http://web.mit.edu/jlcohen/www/papers/Furtadoetal_GRL16.pdf

which has been updated.

http://www.aer.com/science-research/climate-weather/arctic-oscillation

[Richard Dixon]

On Wednesday, 30 November 2016 13:25:18 UTC, Smartie wrote:

Rich - could you plot similar for DJF QBO please?

David - per your request. Slight upward trend in the CET with increasing DJF QBO index (that other ASO QBO chart had a flat trendline). The lowest value there of about -27 was the 2013/14 which was a windy winter, IIRC?

Richard

[Paul Garvey]

Excellent sense Mr. D and entirely in line with my own comments - posted many times. The small - and they are small - improvements in seasonal forecasting are not yet enough to lead to even reasonable accuracy in seasonal forecasting. 

[Smartie]

Thanks Rich. I presume the title should be  "DJF QBO vs DJF CET"...

Keith mode- could you highlight/label winter 2009/2010 (Cold December), 2012/2013 (January SSW and late cold March April) and 2013/2014. please?

[Richard Dixon]

On Thursday, 1 December 2016 11:19:00 UTC, Smartie wrote:

Thanks Rich. I presume the title should be  "DJF QBO vs DJF CET"...

Headings and axis titles....the bane of my life.

 

Keith mode- could you highlight/label winter 2009/2010 (Cold December), 2012/2013 (January SSW and late cold March April) and 2013/2014. please?

See below. You've learnt well from the master in asking for additional detail...

Richard

 

[Smartie]

Thanks- which winter  is the outlier, bottom right with CET ~-1.6 and QBO ~+1.2?

Another Keith type request- can you colour the points according to the NAO index, say with a bipolar heat scale?

[Richard Dixon]

David - oddly enough I am working on adding in NAO already !! I realise that one variable will not do in this sort of thing. However I'm working on NAO vs QBO with colour-coded CETs.

I'm going to try and put it all in Tableau and hopefully embed the code into Google Groups so people can actually interact with it...

Richard

[Richard Dixon]

Here's trying some code - that I imagine won't work:

<div class='tableauPlaceholder' id='viz1480595204292' style='position: relative'><noscript><a href='#'><img alt='DJF NAO&#47;QBO vs CET ' src='https:&#47;&#47;public.tableau.com&#47;static&#47;images&#47;DJ&#47;DJFNAOQBOvsCET&#47;Sheet1&#47;1_rss.png' style='border: none' /></a></noscript><object class='tableauViz'  style='display:none;'><param name='host_url' value='https%3A%2F%2Fpublic.tableau.com%2F' /> <param name='site_root' value='' /><param name='name' value='DJFNAOQBOvsCET&#47;Sheet1' /><param name='tabs' value='no' /><param name='toolbar' value='yes' /><param name='static_image' value='https:&#47;&#47;public.tableau.com&#47;static&#47;images&#47;DJ&#47;DJFNAOQBOvsCET&#47;Sheet1&#47;1.png' /> <param name='animate_transition' value='yes' /><param name='display_static_image' value='yes' /><param name='display_spinner' value='yes' /><param name='display_overlay' value='yes' /><param name='display_count' value='yes' /></object></div>                <script type='text/javascript'>                    var divElement = document.getElementById('viz1480595204292');                    var vizElement = divElement.getElementsByTagName('object')[0];                    vizElement.style.width='100%';vizElement.style.height=(divElement.offsetWidth*0.75)+'px';                    var scriptElement = document.createElement('script');                    scriptElement.src = 'https://public.tableau.com/javascripts/api/viz_v1.js';                    vizElement.parentNode.insertBefore(scriptElement, vizElement);                </script>

But failing that - here's a link!

https://public.tableau.com/profile/richsdixon#!/vizhome/DJFNAOQBOvsCET/Sheet1

Much more a correlation with NAO...

Richard