Autumn and Winter

[Paul]

It's not on the site at all yet SB - should be fairly soon though

[frozen_north]

Thats going to be an excellent tool for cold/snow rampers.

Scenario - Its November and the model shows easterlies for the whole of february and really cold temperatures. The rampers are going to go crazy.

It will be interesting to see the charts though. Especially in FI land e.g. 180-384h to see how it compares to the gfs at this range.

[AtlanticFlamethrower]

Too short. Just too short a period to make any judgements about pattern changes. Also, your last sentence means that you were thinking something was a certainty and there aren't any! This winter could be a reprise of 62/63. 200/1 against it, but it is possible!

Dawish, what do you consider enough time to identify a pattern change? One year's enough, surely?

Last season's synoptics showed sustained northern blocking which for some time kept away mild Atlantic westerlies; this was by definition and widely agreed to be a change of pattern from recent years.

There was a pattern change.

What I think you are suggesting is this pattern change was a blip.

On what evidence could you make that claim? What models/theories are based on time that hasn't happened yet? As far as I can recall: none. Future time awaits observation and recording.

Why should time matter anyway? If we have enough data and a good enough model we can predict a pattern change ahead of time. Of course, we don't; but the principle is that you can.

You can pretend last season didn't exist and make your prediction based on previous seasons. But that would be a judgement based on selective reading of the data - omitting last season's pattern change!

IMO there was a pattern change. Will the pattern of last season continue? I think so.

Aaand... I'll take that bet.

[Dawlish]

Morning Atlantic (another wet one down here),

Give it 10 years, Atlantic, then I'd be talking change, but I'd need 20, to be convinced. After 5, I'd start to get interested. One year is far more likely to be a random fluctuation, than it is to be evidence of a change. Consider this graph (I've managed to attach it below, as well! Amazing. A first for me........I know, I know, old hat to many!):

http://www.whrc.org/resources/online_publi...CO2-Temp-SM.jpg

It infers a strong correlation between CO2 and rising temps, it's one of the reasons why reason why I'd go 1/3 on CO2 being the major cause of GW, but that's not what I'd like to concentrate on. Just have a look at the temperature line. It is erratic. The trend towards warming temperatures, back to around 1950, or the mid-1960's, or the mid 1970's, is there and there has been warming since all those times, but it could easily be argued that 1950 wasn't the start, or that the mid-1960's wasn't the start. However, You'd be really hard pressed to say that the Global Warming trend wasn't under way by the late 1970s.

NASA goes with "More specifically, there was slow global warming, with large fluctuations, over the century up to 1975 and subsequent rapid warming of almost 0.2°C per decade."

http://data.giss.nasa.gov/gistemp/2005/

When you are at the start of a trend change, it is difficult, almost impossible to know that you are at the start of a trend, but applying your reasoning (and that of some others, on here), you could be shouting "pattern change", on every downward dip of those graphs. We've already had a fair few saying that we have a cooling trend in UK temperatures over the last 4 years, therefore we have a trend. That's the same as saying (before last year) that Global Warming stopped in 1998, as that used to be the warmest year ever. That wasn't correct, as NOAA has calculated the extreme El Nino that year could have added as much as 2C to the global temperatures. 2005 stopped that argument completely. I don't think anyone is still claiming that to be true. The odds are, based on the trend, that a UK year will have a CET higher than in any of the last 4. It could be this year, despite a below average start to the first 3 months.

The last example would be cherry picking to try to prove a point - which I feel is happeneing here with the 1yr/18 month pattern change stuff. 5 years of a pattern change and I'd be starting to get interested; 10 years and I'd be talking about it; 20 years, I'd be convinced.

Patterns can only be identified in hindsight. Modelling can extrapolate the pattern into the future, but there are no certainties. Identification of patterns takes time and single years cannot be used as identifiers of change. That's why I say that a 1yr/18 month pattern change is statistically useless. Much of the identification of the trend, I'm sure, is down to finding something to back a belief, which is really, really, poor science and is a result of hope - in this case, for a colder winter. Many people are hoping that the cold weather over Russia and Eastern Europe that "near missed" us last winter, will be repeated. There is nothing wrong with that hope: hope away, I'm rather hoping for some decent snow myself, but leave it right there, as a hope. My challenge is to the spurious application of science to identify a pattern change and somehow justify the hope.

I hope that's answered your question, Atlantic; it was a good one. Would someone who believes we have already seen a pattern change answer these 5 questions, in return? I know some of you will enjoy the research, as much as I did the trends.

1. What pattern change are we talking about? (I think I know that one, but let's be clear).

2. When did that pattern change start?

3. Is it really continuous, outside of a small part of last winter?

4. Was there actually an established winter synoptic pattern for this new pattern to chage from?

5. What is the justification for saying that the change will continue into this winter?

Refards, Paul

[Snowly does it]

1. What pattern change are we talking about? (I think I know that one, but let's be clear).

2. When did that pattern change start?

3. Is it really continuous, outside of a small part of last winter?

4. Was there actually an established winter synoptic pattern for this new pattern to chage from?

5. What is the justification for saying that the change will continue into this winter?

Refards, Paul

I'll try.....

1) Quiet Atlantic with more blocking at higher latitudes

2) Feb 2005

3) No pattern is continuously 100% but the Atlantic/zonal conditions have not been prevalent since that time outside of short bursts (edit, and I think the period coming out of the traditionally Atlantic autumn is key to seeing if the theory is in any way right)

4) For many years previously winters had been generally dominated by Atlantic influences.

5) None whatsoever apart from the change if accepted holding the throne and a change being necessary to unseat it, I.E the status quo remains until a change is recognised.

Thats how I read it anyway. I would say however that I'd actually expect these sorts of things as the globe warms, it necessarily affects weather patterns and some of those will inevitably have a slight cooling effect locally whilst the globe continues to warm, well, globally.

[The PIT]

Well this morning sounded like Autumn. Wind in the trees rain on the roof and Window. Looked outside and it looked like Autumn with leaves on the road. Checked the temps and this showed it was an illusion. Scoffed at Helen Willets saying it feels chilly. It certainly doesn't it just shows that People are getting used to High temps.

[Snowly does it]

Well this morning sounded like Autumn. Wind in the trees rain on the roof and Window. Looked outside and it looked like Autumn with leaves on the road. Checked the temps and this showed it was an illusion. Scoffed at Helen Willets saying it feels chilly. It certainly doesn't it just shows that People are getting used to High temps.

To be fair Pit, it is about average for the time of year right now and it does feel chilly compared to the recent warmth, at least here anyway.

[The PIT]

To be fair Pit, it is about average for the time of year right now and it does feel chilly compared to the recent warmth, at least here anyway.

Well here it's above average here so I guess it depends where you are. Like I said it shows people are getting used to Higher temps. I guess we've got another Winter of comments like "it's freezing" when the air temop is 8C 6.30 Jan morning.

[JoeShmoe]

From the perspective of Western Europe, the hemispheric pressure belts have become displaced further North with an ever Northward march of the ITCZ peaking last Summer. This has led to a more northerly jet and more High pressure to our SW and over Europe.

This to me is the key factor the last 20 years. The displacement of the subtropical belts. Quite often they go so far north that we get the Azores ridge into Greenland but the PFJ has been so far north for a lot of winters recently that its difficult to get those deep cold pools ridging where we would need them to

The reasons .. probably as simple as increased SST's

Will this winter be cold after a record breaking summer again. I think personally its very very unlikely. However we all now think temps around 4-6c are very cold as were so accustomed to milder conditions

[Upgrade]

personally i'm going for a mild, cloudy winter with a lot of rain in the North and West, and less in the South and East. I think the days of powerful Northerly incursions are behind us, there is far less arctic ice around and it is much warmer up there than it was 20 years ago so can't get cold air down to use. Easterly's are half hearted today too. I think those hoping for a snowy winter will be disappointed. just a stab in the dark but that's my view, based on previous winters.

i think everyone (myself included) wants a snowy winter to prove they can still happen in the UK, as if to reassure ourselves that global warming isn't happening. I think we're going to be clutching at straws again all winter long. Why not just declare winter to be over already (do i get a prize for being first to say this?)

[Osbourne One-Nil]

For the first time in my life, I would be quite happy with a mild, damp winter. I'm getting old and my joints hurt you see.

[Summer of 76]

For the first time in my life, I would be quite happy with a mild, damp winter. I'm getting old and my joints hurt you see.

Same here, OON the Honda has gone missing on the web cam

[Michael Fishermans Friend]

For the first time in my life, I would be quite happy with a mild, damp winter. I'm getting old and my joints hurt you see.

Its been along time since you have had your cold winter payments from the Government OON, and well at 99 I can't blame you for wanting a mild winter, I think we'll get one!

[summer blizzard]

Oh no.., the dark side is rising...

Dawlish, the change actually occure in mid-January when the SOI went positive however as with the pattern change last November, it took three northerly bursts before the pattern flipped completely.

While i see the logic Dawlish, in the past two winters, we have had several cold spells as is represented by Phillip Edens data...

February 2005 - second half produced a CET of 2.6C

March 2005 - first half produced a CET in the range of 3.5C

November 2006 - second half produced a CET of 1.6C

January 2006 - first third produced a CET of 0.9C

March 2006 - first half produced a CET of 2.6C

While i would give 3 to 1 against a below average winter, i see no reason why this winter cannot be below average.

[BLAST FROM THE PAST]

personally i'm going for a mild, cloudy winter with a lot of rain in the North and West, and less in the South and East. I think the days of powerful Northerly incursions are behind us, there is far less arctic ice around and it is much warmer up there than it was 20 years ago so can't get cold air down to use. Easterly's are half hearted today too.

Yes it is warmer 'up there' than 20 years ago but I'll say for one more time "not as warm as 30s and 40s" and biting winters were had in the 40s.

Dawlish, I'm intrigued by that chart that shows about a 3F rise in global temps since 1920? Strange that as recorded global increase was 0.6C for the 20th century? Your odds though are reflecting the form horse and that is where, how shall I put it, the wise money will go.

Re mention of the effects of solar minima there is an 'experiment' shall we say in a place in Siberia where they have measured such effects to have a 2 year time lag...so 2008 is my reckoning.

BFTP

[Michael Fishermans Friend]

November 2006 - second half produced a CET of 1.6C

I find that fact quite amazing (if its correct), there was a huge north to south anomoly during that month though, here in Essex an average temp for that month was nearer to 6.75C largely due to the fact that the south took some cooling down due to the mild September and October beforehand. I personally think thats why we will still see an above OCT CET due to the land still being so warm and associated SST's around our coasts still being in the + state.

[Dawlish]

While i would give 3 to 1 against a below average winter, i see no reason why this winter cannot be below average.

That's not far off my own thinking.

[Osbourne One-Nil]

Let's save references to gambling odds for the relevent thread please.

[AtlanticFlamethrower]

Dawlish, why rattle off a post about Global Warming when what I believe Ian Brown was referring too, and I'm interested in, is this winter's weather (and, at a push, maybe next winter too)?

Who is discussing Global Warming?! Who is objecting to Global Warming?! This is the wrong thread and board to discuss hockey sticks of Global Warming.

Last winter showed cold synoptics are still possible. That's significant. It's significant because it's a pattern we have not seen for many years. It was even thought that Global Warming made southerly jet impossible - evidently, not so.

You have said a few times Global Warming does not preclude freezing winters. Are the chances raised this coming winter might be an exception? If there are reasons to believe the pattern of 2005/6 might continue then I put it it is reasonable to suggest this winter might deliver the "cold of old."

A discussion about Global Warming and how we won't know anything for 20 years, while interesting, especially when it's well written and backed up with sources, does not help shed light on this winter, particularly after last winter's eastlies bucked a decade plus trend oft winters during which the Atlantic was nearly always dominant.

Constant effort to put all weather discussion in the context of Global Warming, and to ignore a possible tipping point last season, makes it difficult to look objectively at the here and now which might or might not follow a warming trend. As you have said a colder than average winter is possible.

Relevant question is how significant are the synoptics of last year? Your answer "wait 20 years and ask me then" seems to be equivalent to "not significant". On the other hand I think those easterlies were significant, especially as the winter ending 2004/5 packed a snowy punch.

I'm going into this winter expecting more frequent easterlies and a colder winter to 2005/6. Is this part of a long term trend to cold? I don't know, I wouldn't want to have a discssion whether it is, or isn't. It's irrelevant.

[Dawlish]

Dawlish, why rattle off a post about Global Warming when what I believe Ian Brown was referring too, and I'm interested in, is this winter's weather (and, at a push, maybe next winter too)?

HI Atlantic,

Mainly because you asked me a question about possible changed synoptics. I don't agree with your interpretaion and that disagreement needs explanation. The explanation depends on a UK warming trend and the warming trend is being caused by Global Warming.

There are 5 good questions at the end of my post, in answer to your good questiona bout a possible pattern change. Why not have a go at them?

Maybe you'd like me not to explain fully, then the ideas about a one year pattern change and a possible colder winter would look much more believable, in the absence of contradictory arguments? There is a chance that this winter could be as cold as you feel it will be. I'd put it at 20%; of course, you have every right to disagree and to state that case - I enjoy reading your views - but if you state a view, you must be prepared to read another's point of view, however much you may not like them, or agree with them. The warming trend we are in has every relevance to the coming winter; far more relevance, in my opinion, than a possible analogue to the conditions of last winter. Some of the stuff I read about a coming colder winter annoys me to death, but I try to keep those feelings in check and argue the opposite case in a decent, forthright, way.

The influence of the Global Warming trend is something that the UK is very unlikely to be immune to. It affects the possibilities for the coming winter and it's influence needs to be explored, just as much as the cold-loving arguments for a colder winter.

Paul

[Paul]

Please keep discussion on global warming to the appropriate topic - we're all aware of global warming, but on the flipside of that most (if not all) would agree that an apparent long term trend will not neccessarily have any impact on a short timescale item - such as the british winter this year. So perhaps we can keep to discussing the likely synoptics and shorter term drivers of this winter as they are far more relevant at this stage imo than what has happened for the previous x years.

[coldfingers]

Well it has certainly been autumn the last two days, turned a corner down town today and nearly got blown over by a gale force gust coming off the sea. The leaves on the trees are finally starting to begin showing autumn colours too.

[kippure]

Any one heard about this?

[BLAST FROM THE PAST]

Any one heard about this?

Yes the one written by the 'great' Ian MaCaskill and another? They also talk about the chances in their opinion of such winters re occuring?

BFTP

[kippure]

Is it out yet? Cant wait to read it.