December CET

[Stratos Ferric]

I don't disagree that as a general frame of reference the 30 year baseline is THE baseline. However, the fact remains that in a cycle of constant directional change, particularly as we have at present which is an open-ended cycle, a LONG historic reference does introduce a mainingless skew when it comes to assessing the likelihood of future outcomes. If you look back at the thirty years of performance from 1971-00 in English football Chelsea would not figure in the top 10! Derby would, as would Notts Forest. Hardly a basis for judging the coming year, though, equally, a very telling measure of just how much things have changed.

[pottyprof]

While football statistics may/may not be interesting to some, we have an area for that in the Retreat.

Please stay on topic or have your posts edited/deleted.

SF.. I'm leaving your post as is because it does highlight a statistical point.

[Joneseye]

At the moment I think Philip's CET will finish between 6.6 and 6.8, with 6.7 my favourite. I'm basing this on the likelihood of it being at 6.3C by tonight, after which it will be a sharp rise for the remaining 4 days. Hopefully Hadley will be a decimal place higher than this thanks to the inversion!

Current CET according to © Philip Eden is 6.2C

[West is Best]

Current CET according to © Philip Eden is 6.2C

Strictly speaking it's 6.25C rounded down. http://www.climate-uk.com/graphs/0612.htm

I'm fairly unfazed, although it might mean 6.6C rather than 6.7C is the more likely. We shall see - I might be over-estimating the extent of the rise over the remaining 4 days, although an average rise of 0.15C is more than possible.

[West is Best]

I don't disagree that as a general frame of reference the 30 year baseline is THE baseline. However, the fact remains that in a cycle of constant directional change, particularly as we have at present which is an open-ended cycle, a LONG historic reference does introduce a mainingless skew when it comes to assessing the likelihood of future outcomes. If you look back at the thirty years of performance from 1971-00 in English football Chelsea would not figure in the top 10! Derby would, as would Notts Forest. Hardly a basis for judging the coming year, though, equally, a very telling measure of just how much things have changed.

I see where you, and perhaps Snowmaiden, are coming from, and this is an interesting discussion (go easy on us therefore Pottyprof!).

I think my problem here centres on what I see as a telling phrase: 'when it comes to assessing the likelihood of future outcomes'. I have a serious doubt as to whether the CET is the right tool for this job. It is an historic temperature series which tells us how the climate in a given month, season and year compares to 347 years’ of data. I'm not sure it should be used as a predictive tool, although I can see how this could be done if you can demonstrate pattern changes, and I can see the temptation to use it in that way.

My caution on this derives, I think, from my previous remarks about the long-term nature of what we’re dealing with here. Whilst some aspects of climate change may induce stark and marked short-term fluctuations in as small an area as central England, I am wary about taking a long-term micro measurement like this and projecting it on the grander scale; at least not without extreme care. Yes, I do think the CET gives an indication of the bigger picture but we need time to assess that: I’m thinking decades rather than years, and certainly not months. And in this light I’m doubly cautious about wanting to use the CET as a predictive tool.

I’m prepared to accept that I am being an old fuddy duddy (and I may be completely wrong and will change my viewpoint), but I prefer to think of the CET as a way of measuring how the temperature in central England has varied against the past 347 years. Anything more needs great care.

[Stratos Ferric]

I see where you, and perhaps Snowmaiden, are coming from, and this is an interesting discussion (go easy on us therefore Pottyprof!).

I think my problem here centres on what I see as a telling phrase: 'when it comes to assessing the likelihood of future outcomes'. I have a serious doubt as to whether the CET is the right tool for this job. It is an historic temperature series which tells us how the climate in a given month, season and year compares to 347 years’ of data. I'm not sure it should be used as a predictive tool, although I can see how this could be done if you can demonstrate pattern changes, and I can see the temptation to use it in that way.

My caution on this derives, I think, from my previous remarks about the long-term nature of what we’re dealing with here. Whilst some aspects of climate change may induce stark and marked short-term fluctuations in as small an area as central England, I am wary about taking a long-term micro measurement like this and projecting it on the grander scale; at least not without extreme care. Yes, I do think the CET gives an indication of the bigger picture but we need time to assess that: I’m thinking decades rather than years, and certainly not months. And in this light I’m doubly cautious about wanting to use the CET as a predictive tool.

I’m prepared to accept that I am being an old fuddy duddy (and I may be completely wrong and will change my viewpoint), but I prefer to think of the CET as a way of measuring how the temperature in central England has varied against the past 347 years. Anything more needs great care.

You're absolutely right: at best the use of CET would be as an extrapolative tool for the temperature in the CET zone; no more, no less. Furthermore, any time series smooths linearly: as we are often wont to observe on here when comments from the "it's got cooler this month, where's your GW now" fraternity abound, there will always be variations around the mid point, HOWEVER, these oscillations occur within fairly tight bounds (I haven't time to check before my train arrives in Edinburgh, but I'd reckon that +/- 2C at most accounts for around 95% of all months - and +/-4C has almost never been breached, hence why a 1947 / 63 is now for all intents and purposes out of reach given that the baseline is now approaching 2C warmer than was the case back on the 60s).

Therefore, in a generally flat trend (typical of much of the CET's history) the CET provides poor predictive potential. At present, the 30 year series understates the current warming, and for now at least the 10 year series does provide an indication. What an extrapolation can never do on its own is signal a sudden change, whether upwards or downwards: what comparison of different series can do is show direction; hence, at present, the ten years series will lie higher than the 30, and the thirty would probably lie above the 100. With that sort of alignment the current trend is undeniably upwards; that view - from a chartists perspective - will not change until the 10 year trend has spent 2-3 years below the thirty year trend: I'm not convinced I'll see that again in my lifetime. Not to say we won't get occasional cold months, but as was the point of SM's post, "cold" will oincreasingly become a relative judgement, rather than an absolute one. It felt cold to me this morning, but there still wasn't any frost.

[Zerouali lives]

It will interesting to see Aberdeen's averege temperature for December. During the past week or so, it seems Aberdeen's temperature has been several degrees lower than everywhere in the UK. In fact, apart from yesteday evening, the temperature seems to have been either freezing or below for about a week now! The frost has hardly lifted here for about 10 days in a row now.

[LadyPakal]

I found this page interesting Zerouali.

http://www.aamfc.org/weather/weekrep.htm

You may have seen it before - it's data from a weather station run by an model aircraft club based in Dyce I think. They have a live local weather page (http://www.aamfc.org/liveweather.html) but I've noticed that the rainfall doesn't always record what I see here in the city. It has also been a bit warmer in Dyce than what I have recorded in my garden here during this cold spell.

[Zerouali lives]

I found this page interesting Zerouali.

http://www.aamfc.org/weather/weekrep.htm

You may have seen it before - it's data from a weather station run by an model aircraft club based in Dyce I think. They have a live local weather page (http://www.aamfc.org/liveweather.html) but I've noticed that the rainfall doesn't always record what I see here in the city. It has also been a bit warmer in Dyce than what I have recorded in my garden here during this cold spell.

Hi Julie - I'm surprised your garden has been recording lower temperatures than Dyce. My current temperature (West End) is 1.9° whereas Weather Online have it at -0.7°. With these relentless freezing temperatures I think we could be in for a below average month.

Any pictures of the River Dee lately? I would say ice build up is a possiblity down there now?

Edited December 28, 2006 by Zerouali lives

[LadyPakal]

I took some yesterday - it is amazing around the Duthie Park area - there is one in the short term weather thread - page 4. People were skating about on the iced up boating lake in the park and one kid was riding a bike around on the ice - daredevil. Here: http://www.hardgate.net/park.jpg

Currently -0.8 in my garden right now and barely got above freezing today (I think I'm in a cold pocket here). Been extremely parky here for the last fortnight, apart from a couple of cloudy spells where the temps rose.

Edited December 28, 2006 by LadyPakal

[Optimus Prime]

Indeed, it's been noticeably cold up in NE Scotland lately. The actual anomaly according to Philip Eden for North East Scotland is just 0.7c above average on the 25th. More likely to be 0.5c above now while Ireland is average.

I suspect by the end of the month Scotland will be 0.7c above normal. While parts of the south east may be as much as 2.0c above.

[West is Best]

Philip's CET as of last night was 6.3C http://www.climate-uk.com/graphs/0612.htm

This is actually 6.35C, so the rise in 24 hrs was 0.1C (I'm not quite sure why he's rounded this down as he was previously rounding to evens).

Stratos - excellent post from you and with which I find no disagreement at all.

Edited December 29, 2006 by West is Best

[Weather-history]

There has never been a December with a CET of 5.9, despite a number having a CET of 5.8 or 6.0

And there still isn't one. A real statistical oddity.

[West is Best]

6.4C on Philips' scale up to last night. Given just how exceptionally mild tonight has been (15C in Exeter at 4 am!) then I'd have thought it's virtually guaranteed to rise by at least another 0.2C by close of the month. The NW tracker is now on 6.66C and racing ahead.

Did we finalise which measurement we are using by the way?! I have favoured the official Met Office one. I know it means a slight delay sometimes, but I think it's right and proper.

[Snowly does it]

6.4C on Philips' scale up to last night. Given just how exceptionally mild tonight has been (15C in Exeter at 4 am!) then I'd have thought it's virtually guaranteed to rise by at least another 0.2C by close of the month. The NW tracker is now on 6.66C and racing ahead.

Did we finalise which measurement we are using by the way?! I have favoured the official Met Office one. I know it means a slight delay sometimes, but I think it's right and proper.

Getting close to our magical steak figure Richard! Last night was indeed a steamy affair, tonight looks less mild but still above average.... 6.6 to 6.8 the range for Phillips now?

I think the official competition figure was Hadley. Hadley WAS 0.1 behind Phillip, but that was pre-inversion.

[Polar Continental]

Riding at 6.25c here in Burton, +1.15c above average.

[West is Best]

bearing in mind there was a lot of hype in places about breaking mild records only a week or so before xmas that pleasant cold inversion spell has put some respectability to it.

Fair enough re. the single month record, but the mild December (following the warmest ever Autumn on record) has put the conclusion to the biggest CET record of them all: 2006 is the warmest year since records began.

Not that I'm unhappy: the fall brings it closer to my guestimate for the month.

Edited December 30, 2006 by West is Best

[West is Best]

I agree with you Tamara.

Part of my desire for mild is the perverse wish just that I want people to realise the truth of AGW (as I see it). I know you may not agree with that, but I'm now convinced by it. If we can change things then I do believe it's not too late in decades to come to get back to proper winters ... and I'd actually love that. I'd love my children's children to be able to wake up in the morning to that silent eerie stillness and white-light that you only get after a proper heavy fall of snow. It's magical. Either way, whether one believes this year is AGW driven or not, it's not something to be exactly delirious about is it? It's pretty damned worrying really.

Edited December 30, 2006 by West is Best

[Snowly does it]

I agree with you Tamara.

Part of my desire for mild is the perverse wish just that I want people to realise the truth of AGW (as I see it). I know you may not agree with that, but I'm now convinced by it. If we can change things then I do believe it's not too late in decades to come to get back to proper winters ... and I'd actually love that. I'd love my children's children to be able to wake up in the morning to that silent eerie stillness and white-light that you only get after a proper heavy fall of snow. It's magical. Either way, whether one believes this year is AGW driven or not, it's not something to be exactly delirious about is it? It's pretty damned worrying really.

Seriously worrying Richard, I am still in somewhat of a shock about it. I truly wonder if even a sub 10 year is now possible.

[Polar Continental]

Hi Paul

Happy upcoming New Year!

I think bearing in mind the dreadful pattern we have had for the whole month that figure is not really that earth shatteringly bad. It is hardly good either and is above average again and nothing to celebrate exactly but bearing in mind there was a lot of hype in places about breaking mild records only a week or so before xmas that pleasant cold inversion spell has put some respectability to it.

Tamara

Hi Tamara,

Happy New Year to you

Yes ironically that warm Euro high produced our coldest weather of the season so far, as you say,if not not for that inversion of cold air, (which lasted around a week here) I think we could have been seriously looking at one of the warmest Decembers ever.

Lets hope we see a big turn around in January, I have gone for a pattern change around the 12th, more of an educated guess really, so I am sticking to my 2.2c

Paul

[Stratos Ferric]

Seriously worrying Richard, I am still in somewhat of a shock about it. I truly wonder if even a sub 10 year is now possible.

Probably not without a major volcanic eruption; there'll be one along some time.

[WBSH]

Part of my desire for mild is the perverse wish just that I want people to realise the truth of AGW (as I see it).

Problem is WIB, even if the next 10/20 years were to end up warmer than the last, a common believe that may still prevail is that "the world goes through warming/cooling cycles anyway and this is just a warming one" ... Whether that belief is valid is an entirely different topic altogher though.

So from what I gather 2006 looks set to be warmer than 1998?

[West is Best]

Very true WBSH.

Philip's penultimate measurement is 6.5C. This is actually 6.55C rounded down, so it will either finish on 6.6C or 6.7C. http://www.climate-uk.com/graphs/0612.htm

I'd have thought there's a fair chance the Met Office Hadley figure will be a notch or two higher than this. Rainfall is now above average, though sunshine is too. The NW tracker is on 6.73C, so will be touch and go whether it makes it to 6.8C (probably just short).

[Paul]

Interesting month this one - my punt back on the 20 somethingth of November was 7.1c and was based on the CFS model (we're creating a new CET forecast from it). So the fact it's going to be well within half a degree of the actual CET is a very good sign!

[stormchaser1]

Morning everyone

looks like my 6.4c is still looking good , as of yesterday i am 0.1c out

nigel