Winter 2013/2014 Forecasts/Hopes/Discussion Thread

[UV-RAY]

 

 

 

 

Is it?

I posted some correlations recently between September ice extent (source ArcticROOS) since 1979 and Eurasian winter snow extent  since 1972 (source Rutgers snow lab) which shows a moderate to strong -ve correlation of -0.63 ie less summer ice is followed by more winter snow - http://forum.netweather.tv/topic/77585-snow-and-ice-in-the-northern-hemisphere-201314/page-15#entry2795836

 

 

Here in order are the top 10 lowest ice years and their Eurasian winter snow ranks

	Winter snow rank2012	32007	72011	42008	292010	52009	62005	92002	22006	392003	28

The missing 3 snowiest years were number 8 which was 2004 which just missed out on low ice at number 12;

1985 at number 10 was 23rd in ice table and snowiest year 1977 was before ice data available.

 

But that kind of reinforces my point as we have very little data to back up such a correlation. As we are told arctic  ice is at it's lowest  for a thousand years, much of this has happened over the last decade or so. So with that we have to say that post 80 ice conditions were far more favourable for retention of ice during the summer, more so during the 40's, 50's and 60's with these producing some very cold winters throughout these periods. Then going back further to the times of the Maunder and Dalton minimum we have to presume also that ice conditions in the arctic were far more extensive that they are now, I see a very weak correlation nothing more.

Edited October 7, 2013 by Sceptical Inquirer

[Interitus]

But that kind of reinforces my point as we have very little data to back up such a correlation. As we are told arctic  ice is at it's lowest  for a thousand years, much of this has happened over the last decade or so. So with that we have to say that post 80 ice conditions were far more favourable for retention of ice during the summer, more so during the 40's, 50's and 60's with these producing some very cold winters throughout these periods. Then going back further to the times of the Maunder and Dalton minimum we have to presume also that ice conditions in the arctic were far more extensive that they are now, I see a very weak correlation nothing more.

 

Well that's the data as it stands, which backs up by much of the current research and thinking, versus your supposition, fair enough.

[chionomaniac]

The correlation is still probably there, SI - it just may have not been significant until the ice levels were at record low levels. Just because other factors have overridden the low sea ice values before it became significant, and these factors could still give the UK cold winters back then, doesn't nullify the correlation that is shown now, except perhaps in your eyes?

[UV-RAY]

The correlation is still probably there, SI - it just may have not been significant until the ice levels were at record low levels. Just because other factors have overridden the low sea ice values before it became significant, and these factors could still give the UK cold winters back then, doesn't nullify the correlation that is shown now, except perhaps in your eyes?

I didn't say it did nullify the data, just that the correlation is a weak one Chion.

Well that's the data as it stands, which backs up by much of the current research and thinking, versus your supposition, fair enough.

There's no need to get uppity about it, I said the correlation is a weak one  for the very reasons I stated not that it doesn't exist. Geez!

[Methuselah]

The correlation between summer ice and the following winter is a weak one too say the least and like Blast says this year temp 80 degree north have seen well below average temps, we also have to remember the state of the ice pack prior to its rapid decline what was the causation for some of our past very cold spells. There is still far more research needed in this field and as of yet I still feel we are fumbling in the dark for an answer.

Indeed, SI; if it wasn't weak and tenuous, forecasters would have made noticeable use of it by now?

[Interitus]

I didn't say it did nullify the data, just that the correlation is a weak one Chion.

There's no need to get uppity about it, I said the correlation is a weak one  for the very reasons I stated not that it doesn't exist. Geez!

 

Does it really matter if we don't have data going further back? Of course it would be good, but it's the correlations that are occurring now which are important. In the course of a few more years it could be shown to have been largely coincidental, but at the moment the correlations are there and real, download the data and look for yourself.

[Interitus]

Indeed, SI; if it wasn't weak and tenuous, forecasters would have made noticeable use of it by now?

 

Not sure how noticeable use would be defined, but guaranteed that they are aware of it. Page 23 of this Met Office presentation shows them using Autumn snow extent for winter seasonal forecasting for example quote "High snow in Autumn => -ve winter Arctic Oscillation" - which is affected by ice levels - http://www.metoffice.gov.uk/media/pdf/4/n/MOSAC17.12_SRG9.12_Scaife.pdf

[BornFromTheVoid]

While the correlations in and of themselves don't demonstrate a definite causal relationship between sea ice levels and mid-latitude weather (you can find correlations between almost anything) what does make the relationship more convincing are the many different physical mechanisms that have been purported to cause the relationship.

We have the connections with the stratosphere, the connection with snow cover, the connection with the reduced thermal gradient and others. We have several mechanisms, with strong foundations in the physical sciences, that may be working together to drive changes in the hemispheric circulation patterns. While we'd all like more time to create more robust correlations, the most important thing to me is that you can make predictions and test them. With all the observational data at our disposal these days, this is very doable, and the the proof can be found in the massive amount of papers being released on this topic and the new connections being discovered.

 

Basically, removing so much reflective sea ice and replacing it with open ocean is going to cause huge changes in terms of heat, moisture and momentum flux, way up through the atmosphere. While finding all the mechanism for the relationship with our weather may take some time, it is extremely improbable that these change could have no impact.

Edited October 7, 2013 by BornFromTheVoid

[AWD]

A blog courtesy of Liam Dutton, mentioning the current Eurosian snowcover and the possibilities this could produce come winter;

http://blogs.channel...chill-week/5054

[Boro Snow]

heres the link the above doesnt work

 

http://blogs.channel4.com/liam-dutton-on-weather/northerly-wind-bring-chill-week/5054#more-5054

Edited October 7, 2013 by Lee aka Boro Snow

[lorenzo]

Not sure how noticeable use would be defined, but guaranteed that they are aware of it. Page 23 of this Met Office presentation shows them using Autumn snow extent for winter seasonal forecasting for example quote "High snow in Autumn => -ve winter Arctic Oscillation" - which is affected by ice levels - http://www.metoffice.gov.uk/media/pdf/4/n/MOSAC17.12_SRG9.12_Scaife.pdf

 

Nice link Interitus, puts all the atmospheric variables into a neat timeline, hadn't seen that one before. Bloody 'ell just noticed we are on page 100 LOL!

Edited October 7, 2013 by lorenzo

[Jimmyh]

lee very interesting article. Got some people in the met office sitting up and taking notice me thinks

[Methuselah]

Not sure how noticeable use would be defined, but guaranteed that they are aware of it. Page 23 of this Met Office presentation shows them using Autumn snow extent for winter seasonal forecasting for example quote "High snow in Autumn => -ve winter Arctic Oscillation" - which is affected by ice levels - http://www.metoffice.gov.uk/media/pdf/4/n/MOSAC17.12_SRG9.12_Scaife.pdf

Apologies, Inheritus...I was confusing the high-latitude Autumn snowfall with the long-term extent of the Arctic sea ice... 

[UV-RAY]

Does it really matter if we don't have data going further back? Of course it would be good, but it's the correlations that are occurring now which are important. In the course of a few more years it could be shown to have been largely coincidental, but at the moment the correlations are there and real, download the data and look for yourself.

I accept they are real but without sufficent data it still remains a tentative link at best, but one which certainly needs keeping an eye on.

[MR EXTREMES]

surely all this northern blocking and cold snap is a little to soon id rather all this was happening around end of November surely this could have a neg effect for the rest of winter.

[Summer Sun]

surely all this northern blocking and cold snap is a little to soon id rather all this was happening around end of November surely this could have a neg effect for the rest of winter.

 

I said the same yesterday this could all come too soon then come winter proper things change

 

For what its worth CFS is showing an average / mild winter again

 

 

Edited October 7, 2013 by Summer Sun

[AWD]

There is no correlation between blocking in October and blocking in winter.

Blocking in October means nothing come winter.

[Yarmy]

surely all this northern blocking and cold snap is a little to soon id rather all this was happening around end of November surely this could have a neg effect for the rest of winter.

 

Why, though? It's not like you can use it all up. It might be flat zonal in Nov/Dec, but it won't be because it's blocked now.

[cheese]

There is no correlation between blocking in October and blocking in winter.

Blocking in October means nothing come winter.

 

 

Bingo.

 

Mr. Sun is just trying to wind people up. October was cold last year, remember, but it didn't prevent the following winter from being chilly and very snowy for some. Certainly, it seemed to drag on forever.

 

 

Edited October 7, 2013 by cheese

[throwoff]

It does seem from the snow and ice etc that we are closer to 2010 than the last two years, of course this far out it means very little but you can fully understand why some people (me included) are getting excited.

 

Let's hope that the match continues into November and as we get to the end of November maybe we will see something.

[MR EXTREMES]

Bingo.

 

Mr. Sun is just trying to wind people up. October was cold last year, remember, but it didn't prevent the following winter from being chilly and very snowy for some. Certainly, it seemed to drag on forever.

 

 

I don't think summer sun is its a fare realistic comment. but its just a lil early but im not saying im not excited because I am every winter since 2009 I have been.

[Methuselah]

There is no correlation between blocking in October and blocking in winter.

Blocking in October means nothing come winter.

Is there a correlation between October's CFS outputs and the subsequent winter? I'd suspect that if there is one, it'll also be somewhat weak...  

Edited October 7, 2013 by A Boy Named Sue

[AWD]

Is there a correlation between October's CFs outputs and the subsequent winter? I'd suspect that if there is one, it'll also be somewhat weak...

I don't use/look at the CFS output. It's not for me. Perhaps CreweCold or someone else who uses the CFS could answer that?

[Skyraker]

A bit like when you were obsessed with the 'large teapot' perhaps Ian  ... Still maybe a valid point.... there are other factors at play and I did cringe a bit when SSW went mainstream to the general public, only because it seemed to devalue the science done by some on here and other elsewhere to the same throwaway phrase as the trashy & much over used 'tipping point'.

 

*edit* I didn't realise Large Teapot came under the umbrella of profanity.. but on reflection.. sure , why not.

It would be extraordinary if at some point between now and December we didn't enter a phase of conventional zonality. The cooling at Northern latitudes and powering up of the jet are to be expected and I hope expectations are not falsely raised by blocking occurring now.Although very interesting and doubtless a factor, I think the SSW thread became too much of an obsession in the last couple of winters and we still need a multitude of factors to consider. What happened in the second half of last winter were persistent low heights over Europe and the jet just deflecting far enough South. We did end up with that exceptional March and early April pattern but IDont think any of the start experts saw that coming.

Edited October 7, 2013 by Skyraker

[Isolated Frost]

No correlation between a cool surface high interlude and mid-October and the winter that follows.