Autumn and Winter

[Snowyowl9]

and the 18 Jan'05 failure:

http://www.wetterzentrale.de/archive/ra/20...00120050118.gif

http://www.wetterzentrale.de/archive/ra/20...00220050118.gif

That was a half failure for here too at 1000ft, although we did have a covering of snow with a period of wet snow 1st thing, but with a rapid thaw later with sleet/hail then rain showers and gales/severe gales which was from a NW the max was 3.8c with a min of -1.0.

[Dawlish]

I can only think of a very small minority of people from Devon. As far as I am concerned UKGW in the name of Dawlish is firmly switched off.

Tamara

??

[Roger J Smith]

Still doing some research for my own winter forecast, so no strong hunches at this point, looking like a more active pattern than last winter which should at least mean interesting weather of some kind, more frequently than 05-06 which might qualify as least interesting winter on record (any stats on that?).

But while we have plenty of time to wait, I have some thoughts about whether recent mild winters (the period 1988-2006 has failed to produce what anyone could reasonably call a very cold winter), are a result of natural variability or AGW (human influences on climate leading to global warming). Many of us tend to believe that it's a bit of both, my own feeling is 3-1 or 2-1 natural over anthro-GW but how to prove or disprove that?

Whatever, it's an evident fact that recent years have been warmer. It's the same thing on this side of the Atlantic, except that over here, our winters are so robust and variable that a shift in trends takes a while to produce any obvious differences in large-scale effects. In those places where it normally snows and turns sub-freezing cold for a few months, it continues to do just that, in slightly muted fashion on the average, but with the occasional brutal winter thrown into the mix.

Here on the west coast (near sea level), where we normally have a mild winter and perhaps a week or two here or there with wintry conditions, all I've noticed since moving here ten years ago from Ontario, is that these wintry episodes seem fewer and further between than I recall seeing them from a distance while in the weather mines. Why, they even had their own versions of 1947 and 1963 out here, only they came in 1950 and 1969, and since those two winters, a few rather tame versions have come and gone, much as you had in the 1980s, also here, they were mostly in the 1980s.

So there seems to be a fairly similar rhythm to these variations, as though North America and Eurasia were both undergoing the same slow relaxation of winter's icy grip, indicating of course that the subarctic portions of the northern hemisphere must be warming up, because if they were cooling down we would be feeling the fringe effects of that as was the case in the 19th century, when winters were generally speaking quite a bit longer in much of North America. In fact, when I look at European climate records, I don't see as much warming from 19th to 20th century as is very evident across North America.

Taking Toronto as a good example, when you look at 19th century records, late March, April, May, October and November are all quite a bit colder than in modern times, even before the recent decades of postulated "AGW." Long before the first SUV rolled off an assembly line, it was pretty common knowledge that the 20th century had warmed relative to the 19th century by 2-3 degrees, in fact, by more than many proponents of AGW say that recent decades have warmed up relative to the 1960s or 1970s.

If you want more precision, there was quite a shift in the temperature series around 1889, so that the decade of the 1890s fits better with the 20th century than the 19th century in the data. I am talking about rural observation sites with no local bias towards urban heating as well as the Toronto records, which were always taken in the centre of a fairly large city. Some sort of natural variation (or a lot of train smoke) must have produced this warming episode. Some believe that Krakatoa's eruption in 1883 cooled the climate (in N America at least) for several years, which it may well have done, but 1883 had been quite cold months before Krakatoa erupted, with one of the coldest Marches on record.

What all this leads me to saying, is that natural variability has been a very large factor throughout all known climate records, both year to year, and decade to decade or century to century. And we are observing all of these against the very slow backdrop of being in the last stages of a major glaciation or "ice age." By all rights, it should be slowly warming up, because the ice is still melting on every time scale except occasionally decade to decade. Baffin Island has lost half of its ice cover since about 1500 A.D., for example, but most of that disappeared long before AGW began.

If there is natural variation at work behind the scenes of the recent warming episode, then we're entitled to ask, what are some of the causes of it? Some talk about being near the peak of a long-term solar activity cycle, meaning that we have large areas of the Sun covered by sunspots each time there is a peak, but while this correlates fairly well over the past few centuries, there's no obvious reason why enhanced solar activity would warm up Europe and not Australia or North America, places where the concept "even larger teapot" would be meaningless.

My favourite explanation is the northward drift of the North Magnetic Pole, which I believe has a strong interconnection with the upper atmospheric flow pattern. If this were the case, most regions would warm up at a time when (as now) the NMP is drifting north towards the north pole. This also fits with the observation that relatively speaking the 19th century was colder in North America than in Europe -- the more southerly location of the NMP (around 70 N) in the mid-19th century, over north central Canada, would clearly influence temperatures more here than there. By the way, the NMP is heading at a fairly brisk pace (by its standards) towards the north pole, but may be headed more towards Russia or eastern Siberia over 150-250 years, a factor which might give you a slightly better chance of a colder winter, but not so much as if the NMP headed for Scandianvia and enhanced the chances of a polar vortex forming over northern Europe.

Other researchers would be more inclined to look at regional connections as part of natural variability. In other words, there is not necessarily any external forcing at all, but just by the random chance of the weather or climate changing in some other region, your region feels a predictable after-effect. One key example of this would be greater melting in the Greenland and eastern Canadian arctic regions. Such melting would tend to fill the western Atlantic basin with more fresh water, which would tend to flow south near the surface and reinforce trough development around 30-50 W. This in turn would increase the chances of a (mild) SW flow over the eastern Atlantic. So here we would have a cause and effect where only the cause of the melting of the arctic ice was actually needed to drive the whole engine of natural variability. Then, if there is a more frequent SW flow in the eastern Atlantic, the Norwegian Sea and North Sea - Baltic Sea basins would warm up dramatically because they have no other source of winter season heating than inflow of Atlantic waters. The warmth of the Baltic Sea last winter, despite the very cold winter going on around the basin on land masses, was evident to me each time I checked, perhaps hoping to see the temperatures heading for the freezing point -- I think they stalled out near 2-4 C.

Who knows, since the time series would be quite long and data available is not that good for many regions before 1700, but there could be a whole series of subtle region to region interconnections that repeat in some vast cycle, against the backdrop of the aforementioned warming or cooling cycles that are on the time scale of ice ages. It could well be that the atmospheric system has built in break points where a given trend short circuits itself and leads to a new and different trend. For example, there were many milder winters in the UK in the 1920s and 1930s as well, then the 1940s turned quite cold by comparison. At that same time, in North America, a cycle of hot dry summers gave way to more normal, rainy summers.

Natural variability is so complex that one can spend a lifetime studying it, and still fail to see many of the patterns, so having a forum like this is a hopeful sign, because a hundred or a thousand minds working together on what all would agree is a formidable intellectual challenge, might be the only plausible way to "crack the code," if in fact there is a code. Since the reality is that perhaps a hundred researchers are working on a hundred different theories, all of which slightly or perhaps more generally overlap, we are reminded of the phrase "each went unto his own way," with the known result that nothing much came of it.

Is there a solution to this? Yes -- a group of people who are not doing research themselves and so have no real vested interest, should oversee all the efforts with a view to identifying which ones are promising, or perhaps, which ones do well in given regions or time frames. Then they could be looking for an overall pattern -- advances in two or three seemingly unrelated problems. It is probably more like auto mechanics than elegant physics with neat equations, in this field -- the car is not running properly, so what's causing that? Your auto mechanic usually looks for a number of things all working with each other to cause the problem -- and that's how we should be approaching this business, I think. There won't be one moment of "Eureka" so much as a long, grinding improvement in LRF as there has been with medium-scale (3-7 day) forecasting in the past 30 years.

But I still say it will be a wild and stormy day on 3 January 2007.

[wellington boot]

The issue, IMO, that is leading many to overstate the upward move in goalposts is the lack of synchronisation of synoptics and cold pooling and is leading to some dangerous assumptions about how much our climate has warmed. Because such winter sychronisation has been awol for some time (in stark contast to the summer equivalent synoptics and 'hot pooling' this year for example) it has led to assumptions being made about climate warming in this part of the world that may very well be skewed and overstated.

I would repeat, that until(or if) those sub -25 OR -30 850's disappear from our charts then we cannot say that all parameters have moved upwards. With further cold pools origins to potentially tap into with the right synoptics then the margin of cold in this country could be as deep as recorded before. It will only need this to happen once to prove the point.

Tamara

I continue to agree with what you say snowprincess; there is certainly no need to jump to conclusions based on the occurrence of unusually warm winters over the last decade. And this reminds me - I have a few issues with a number of your posts Dawlish, so if you (Dawlish) would like to clarify these I would appreciate it:

You tell us that the "one year/18 month trend stuff counts for nothing" and has "no statistical relevance", and then go on to write that you "won't be persuaded by the "well it happened, so it can happen again" argument", shown here:

That's why the one year/18 month trend stuff counts for nothing with me (honestly, sorry to say that, believers in that tiny sample), statistically, it counts ziltch, there is no statistical relevance to it. If that's harsh, for the ones that wish for colder conditions again, maybe it's worth reassessing why they believe that it will get colder? I won't be persuaded by the "well it happened, so it can happen again" argument. Statistically, that is unlikely - not impossible, just unlikely.

Paul

Well firstly, you say you won't be persuaded by the "well it happened, so etc." argument, but in the quote below, you imply that your prediction for the coming winter is entirely based on what has happened in the last few years. So you seem to be saying "well it happened before, in the last few years, so it will probably happen again." I'm not sure that this seems like a very thorough method of approaching a winter forecast. As Snow Princess rightly asserted, "Statistics are vulnerable things - they are there to be knocked down at any time and changed."

7/2 a colder winter, Snowp. Not never; 7/2 against, based on the evidence of the last 15-20 years.

Paul

And continuing on the subject of this post, I believe it is really the last 15 years, since 1990, where any trend has really developed, so I'll assume that you mean that you are basing evidence on the last 15 years or so. Anyhow, you seem to be judging the records and new trends of the last 15 years as statistically significant, unlike those of the last 18 months (a period which accounts for 10% of the last 15 years, incidentally). So is 15 years the exact number of years you have to include in your reckoning in order to be relevant? Why not go back 60 years, in which case, as someone earlier posted, possibly BFTP, you would see opposite trends, certainly for particular, connected factors, such as Arctic temperatures. Surely it's a bit short sighted to draw a line somewhere (perhaps 1990 in this case) and decide that only data collected since then is relevant to your predictions.

Anyway, one last thing. This is not terribly important, and I hope you don't think I'm attacking you for the sake of it, but in the following quote you talk about why you think continued warming is likely, and you mention evidence for this - computer models which predict how far the warming trend might go. Thing is, you then say, "I don't actually believe that, but add the computer predictions to my own calculated probability and the argument for continued warming is very persuasive". I would advise against using evidence you don't believe to back up your argument, and saying that it contributes to your conviction...

Now that is terribly simple probabilities and better minds than my small excuse for one, have developed computer models that can calculate how far the trend can take us. They can factor in, or out, CO2, but the models show that we will not change this trend, whatever happens this century, even by reducing CO2 levels; we are locked into it. I don't actually believe that, but add the computer predictions to my own calculated probability and the argument for continued warming is very persuasive. I've been persuaded and it now has to take a very good argument to show me faults with that reasoning.

[wellington boot]

oh and thanks roger for your very interesting post. I look forward to re-reading it tomorrow and taking it in better.

[tugmistress]

Excellent and well thought out roger, as always

[Dawlish]

What all this leads me to saying, is that natural variability has been a very large factor throughout all known climate records, both year to year, and decade to decade or century to century. And we are observing all of these against the very slow backdrop of being in the last stages of a major glaciation or "ice age." By all rights, it should be slowly warming up, because the ice is still melting on every time scale except occasionally decade to decade. Baffin Island has lost half of its ice cover since about 1500 A.D., for example, but most of that disappeared long before AGW began.

But I still say it will be a wild and stormy day on 3 January 2007.

Nicely written Roger. I look forward to the results of your research. It could be natural variation, that is behind the warming. I'd never discount it, as I'm not fully convinced by the AGW argument, so it could be being caused by something else. Your ideas on the wandering of the magnetic pole are very interesting and the other influences you state are all possible. No-one could equivocally say that any of the things you mention are definitely not behind GW. There just aren't any certainties.

However, the Earth is warming and right now, I'd go 1/3 that CO2 is the major cause.

Paul

[Gray-Wolf]

I see that the end of 'the great depression' and the first world arming for war did a lot to the global dimming issues in the 30's and 40's then (Arctic cooldown) LOL

I've been skimming through to get up to date and I was very concerned, until reading S.M.'s cool post, that no-one had reminded themselves that we are at the stasrt of an ENSO event.

Surely if you are looking for trends then a global pattern shift is going to kybosh any 'new' or emerging pattern? I know a weak event is called for but I don't think the relevant agancies have a good 'handle' on the current El-Nino/Southern Oscillation (surely the NHC, via the NOAA would have called for a quieter Atlantic Basin season earlier if they had spotted the ENSO and the same for our own MetO's 'winter revision' did they also not have their models give them the 'heads up' on the approaching ENSO?)

As such I am adrift with my thoughts for the upcoming season. Of course we could still recieve the 3 to 4 day winter wonders but the 5/6 week blocked patterns that seemed to be starting to occur must be abandoned now surely? The joys of our climate eh?

[Snowly does it]

As such I am adrift with my thoughts for the upcoming season. Of course we could still recieve the 3 to 4 day winter wonders but the 5/6 week blocked patterns that seemed to be starting to occur must be abandoned now surely? The joys of our climate eh?

Would not a weaker to moderate El-Nino send the jet futher south? In which case presumably the blocking patterns (should they occur) would not be disturbed?

[BLAST FROM THE PAST]

Would not a weaker to moderate El-Nino send the jet futher south? In which case presumably the blocking patterns (should they occur) would not be disturbed?

Its a good point SM but GW is very biased towards AGW IMO reading his posts. You are correct re weak to moderate being no bad thing for winter prospects. This winter will be very variable...some good some bad but certainly interesting.

Roger nice posts...first week of Jan is pivotal point

BFTP

[Dawlish]

I continue to agree with what you say snowprincess; there is certainly no need to jump to conclusions based on the occurrence of unusually warm winters over the last decade. And this reminds me - I have a few issues with a number of your posts Dawlish, so if you (Dawlish) would like to clarify these I would appreciate it:

You tell us that the "one year/18 month trend stuff counts for nothing" and has "no statistical relevance", and then go on to write that you "won't be persuaded by the "well it happened, so it can happen again" argument", shown here:

Well firstly, you say you won't be persuaded by the "well it happened, so etc." argument, but in the quote below, you imply that your prediction for the coming winter is entirely based on what has happened in the last few years. So you seem to be saying "well it happened before, in the last few years, so it will probably happen again." I'm not sure that this seems like a very thorough method of approaching a winter forecast. As Snow Princess rightly asserted, "Statistics are vulnerable things - they are there to be knocked down at any time and changed."

And continuing on the subject of this post, I believe it is really the last 15 years, since 1990, where any trend has really developed, so I'll assume that you mean that you are basing evidence on the last 15 years or so. Anyhow, you seem to be judging the records and new trends of the last 15 years as statistically significant, unlike those of the last 18 months (a period which accounts for 10% of the last 15 years, incidentally). So is 15 years the exact number of years you have to include in your reckoning in order to be relevant? Why not go back 60 years, in which case, as someone earlier posted, possibly BFTP, you would see opposite trends, certainly for particular, connected factors, such as Arctic temperatures. Surely it's a bit short sighted to draw a line somewhere (perhaps 1990 in this case) and decide that only data collected since then is relevant to your predictions.

Anyway, one last thing. This is not terribly important, and I hope you don't think I'm attacking you for the sake of it, but in the following quote you talk about why you think continued warming is likely, and you mention evidence for this - computer models which predict how far the warming trend might go. Thing is, you then say, "I don't actually believe that, but add the computer predictions to my own calculated probability and the argument for continued warming is very persuasive". I would advise against using evidence you don't believe to back up your argument, and saying that it contributes to your conviction... :o

HI Boot, good riposte.

Clarify away Dawlish, myboy!

Don't attribute 1990 as the start of the trend to me. 15 years was the time period that BigBear asked us to research similar length periods in the Hadley series for him. If you think there's a 15 year trend, that's fine by me. For me, the UK began to warm in the early to mid 1980s. The world has been warming longer - see the graph on the NOAA site that P3 has referred to on another thread. There has not been a negative annual temp anomaly, since 1979 and the earth has been warming for at least double that time; a trend can easily be seen back to the early part of this century, with a warmer spell, peaking in 1940 - the warming Arctic period that you refer to.

My "prediction", for this winter, is just that the odds are against a cooler than average winter and not a prediction at all. I don't issue "predictions" as I don't think there is an agency on earth that can forecast the nature of our coming winter at this distance, with accuracy. 70% chance warmer than average:20% cooler:10%(ish) average. Statistics are not the vulnerable things that you think they are. They really can give excellent ideas about the future. Insurance companies gamble all the time, using statistics about you and me. For our pension contributions they are gambling on some of us not drawing it for long. Statistics are an essential part of our lives and their application to climatology and meteorology is well established.

I haven't got a clue what you are trying to say in your whistling bit, but if you believe it, that's fine by me.

wellington; it's such a cogent argument that the world is warming, there's a trend and the UK is following suit. Whether you'd like to think so, or not, the trend is more than just recognisable - it leaps out and smacks you between the eyes like a Glasgow handshake. I see no persuasive argument that shows there is any change, in the offing, to that trend and no; a 12/18 month pattern - if indeed there is any pattern; perhaps we are looking for something that isn't actually there at all, but is a few isolated and unconnected instances - means doody. It really is statistically useless.

From that, stems my use of that established trend to look at future years' weather in terms of probabilities. I've been doing it since about 1990, when it began to look, to me, like the UK was beginning to follow the global trend and it has allowed me to forecast the number of warmer months in almost every year since with something approaching accuracy. In terms of warm years, rather than seasons, or months, the proportions are closer to 80:5:15, in the UK. On a world, Global Warming scale, it is at least 90:5:5, maybe even higher, as the NOAA graph shows. A 90%+ chance, next year, of getting a warmer than average year. Would you like to bet that it won't be at evens?

Do the sums yourself and see if you don't end up a little more convinced about what is more likely to happen; or at least a little more informed about where I'm coming from.

Regards, Paul

Edited October 1, 2006 by Dawlish

[North-Easterly Blast]

No, there have been proper cold UK years since 1979; 1985 and 1986 were both cold years with annual CETs below 9*C, and 1996 was the last below average annual CET at 9.20*C.

[ukmoose]

Hi everyone,

I don't make too many contributions but I do read the posts with great interest and there are some very knowledgeable people out there. It all makes for fascinating reading.

I'm more of a 'look at the stats and make a prediction bases on probability' than a forecaster but either method has its drawbacks. I know there are 'lies, damn lies and statistics' but climate is about trends bases on statistics so here goes.

The pattern for the last 15 years or so has been for quite warm autumns and mild to very mild winters. Last winter bucked the trend a little - but frighteningly, if you are a cold lover, despite seemingly 'perfect' conditions for a very cold winter, it never materialised. Contrastingly, when the scene is set for record high temperatures they duly appear (reference July and Sepember this year). Why? Read on.

Most months now are warmer than the long term average (not usually by as much as July and September) and very few are below average (even then by only a fraction).

The net result of these increaing temperatures is that the seas around our shores are steadily warming. Our maritime climate means that our weather is moderated by the sea. As water warms and cools much more slowly than land masses, the current warming trend is having more effect on us that our continental neighbours. Couple that with an increase in the number of days with southerly winds (a warm direction) and it is not surprising that our winters are getting warmer and our summers hotter - the warmer the waters around our shores get, the more influence this warm water has on our winter temperatures - hence when cold weather arrives, it is not as cold as it used to be having been warmed by the sea more than it used to be. Contrastingly, the warmer waters do not cool the summe temperatures as much as before hence warmer sumer temperatures. It is a viscious cycle.

In my opinion, last winter was as close as we can get to a cold one (and it wasn't that cold). If we had the same set up this year as last (which seems unlikely) the winter would not even be as cold as last year's because the sea around us has been heated even more during the hot summer and this has continued in to September.

My forecast for autumn - above average temperatures for October and espescially November (probably not record breaking though) followed by slightly warmer than average winter months with more rainfall than last year but not excessive. Very few frosts in either autumn or winter.

PS Hope I'm wrong though!

Best wishes to all,

ukmoose

[Snowyowl9]

1988 was the 1st of the mild winters and anyone living at sea level especially...I`m very fortunate that I live where I am.... doesn`t have much chance of seeing much unless we do get some very potent northerlies/NW as showed its still possible, like what happened last november in SW wales/cornwall where they had 4 inches....or we can get the Scandi/Greenland high in place to get that Russian air over us and I believe it`s easily possible we could have a cold pool like 1991 again or even 1986 as long as the block held that is,as last winter proved to me it can happen with these temperature inversions and sub 0 days.

:o

Edited October 1, 2006 by Snowyowl9

[Snowly does it]

In my opinion, last winter was as close as we can get to a cold one (and it wasn't that cold). If we had the same set up this year as last (which seems unlikely) the winter would not even be as cold as last year's because the sea around us has been heated even more during the hot summer and this has continued in to September.

My forecast for autumn - above average temperatures for October and espescially November (probably not record breaking though) followed by slightly warmer than average winter months with more rainfall than last year but not excessive. Very few frosts in either autumn or winter.

PS Hope I'm wrong though!

Best wishes to all,

ukmoose

Hi ukmoose, nice post, but I would disagree with you on a point. I don't think last winter was 'perfect' conditions for very cold. It was condusive to cold certainly.

December was unspectacular until after Xmas, and January was dominated by an anticyclone. The real 'perfect' set up came mid Feb to mid March, when temperatures were extremely low compared to recent times.

You are right imo however about the mitigation of cold by the surrounding temperatures, epecially when we draw from the atlantic, however when a direct northerly or Siberian draw occurs, our weather is coming from an acutely colder area.

Had last winter had the 'perfect set-up, I think it would have been significantly colder in terms of the CET return, the fact it was just below average suggests it was a near miss winter for colder conditions.

Be interesting to see what this year brings.

[TEITS]

HI Boot, good riposte.

Clarify away Dawlish, myboy!

Don't attribute 1990 as the start of the trend to me. 15 years was the time period that BigBear asked us to research similar length periods in the Hadley series for him. If you think there's a 15 year trend, that's fine by me. For me, the UK began to warm in the early to mid 1980s. The world has been warming longer - see the graph on the NOAA site that P3 has referred to on another thread. There has not been a negative annual temp anomaly, since 1979 and the earth has been warming for at least double that time; a trend can easily be seen back to the early part of this century, with a warmer spell, peaking in 1940 - the warming Arctic period that you refer to.

Regards, Paul

The problem is though Paul is GW actually responsible for the mild winter's since the 80's or are other factor's responsible. There is no doubt the earth is warming but I don't think it's quiet as black & white as you make it out to be.

Could our mild winter's since 1980's be down to:-

(1) GW

(2) GW affecting our synoptic's

(3) We are just going through one of earth's natural warm cycle's.

(4) Sunspot activity

(5) GW combined with warm cycle

(6) Teleconnections Note Negative NAO during 60's and positive during 80's/90's

My answer is a combination of the list above with (2),(5),(4),(6) being responsible. Now suppose these next few year's we go through a spell with low sunspot activity, Negative NAO like the 60's, change in the synoptic patterns with Northern blocking being dominant rather than LP. We would see winter's like those in the past only the severity and duration would probably be less due to GW.

[Dawlish]

The problem is though Paul is GW actually responsible for the mild winter's since the 80's or are other factor's responsible. There is no doubt the earth is warming but I don't think it's quiet as black & white as you make it out to be.

Could our mild winter's since 1980's be down to:-

(1) GW

(2) GW affecting our synoptic's

(3) We are just going through one of earth's natural warm cycle's.

(4) Sunspot activity

(5) GW combined with warm cycle

(6) Teleconnections Note Negative NAO during 60's and positive during 80's/90's

My answer is a combination of the list above with (2),(5),(4),(6) being responsible. Now suppose these next few year's we go through a spell with low sunspot activity, Negative NAO like the 60's, change in the synoptic patterns with Northern blocking being dominant rather than LP. We would see winter's like those in the past only the severity and duration would probably be less due to GW.

Could be, Eye. There just aren't any certainties. Like I said earlier, I'd go 1/3 that CO2 is the major cause of Global Warming; not certain, but more likely than any other possible cause. I'd apply similar reasoning to the UK warmer winters (and warmer springs, summers and autumns). Any of the factors in your list, could be the main cause and it could be - and probably is a combination of factors, for 2 and 6 could be a consequence of GW affecting pressure belts, but with the global trend being so real, it is hard to feel that our warmth is due to a different cause. On this one, I'd go 1/10. Not certain, but extremely likely, in my opinion.

Paul

[shuggee]

There's recent evidence that we have passed the solar minimum. With 'backward sun spots' indicating a rise in activity again Ian:

http://www.netweather.tv/forum/index.php?showtopic=32064

However, as with the seasons, I'd suggest there is going to be a lag on the effect of the minimum - which may take a couple of years to work through the system?

[shuggee]

Yeah - there's been lots of dates mentioned - but no-one can accurately predict the date of the minimum. Only when it is passed can it be identified by looking backwards. Bit weird that one. I'd heard 2007 banded about for a couple of years - but it looks as though Summer 06 might be the date.

[Dawlish]

Enjoyed reading your post Ian. Couple of points.

"when compared with the pre-defined AGW period".

There's one hell of an assumption in there Ian!

We are approaching a solar minima and there has been a pattern shift in Autumn and Winter synoptics since February 2005. Admittedly not a long sample to draw on but certain synoptic situations that I thought possibly no longer possible have developed.

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!

Paul

Edited October 1, 2006 by Dawlish

[Paul]

Ok, a bit of a give away as to what we're working on for the site at the moment. But this is a chart from the NCEP CFS (climate forecast system), which runs out to 9 months!!

White xmas anyone??!!

Disclaimer - don't take this chart as gospel - it's a climatic long range model which can't be used for specific forecasts at this range!!!

[Snowly does it]

Ok, a bit of a give away as to what we're working on for the site at the moment. But this is a chart from the NCEP CFS (climate forecast system), which runs out to 9 months!!

White xmas anyone??!!

Disclaimer - don't take this chart as gospel - it's a climatic long range model which can't be used for specific forecasts at this range!!!

In the bag!

Excellent toy though!

[kippure]

Will i need this?

[shuggee]

What a lovely chart for a Monday in December.

But of course the anomalously warm N Sea and surface layer will ensure sleet on all but high ground

[summer blizzard]

Can we have the link to that Paul, or is it only available through Netweather extra.