January CET

[LadyPakal]

Reef, You missed my point but never mind. Can't be bothered going into it and I doubt you'd get it anyway.

Edited February 18, 2009 by LadyPakal

[summer blizzard]

Thats exactly the point though. Theres no proof yet that we in the UK are actually cooling. Until we have several years of data suggesting so, at present it is merely a small trough in an otherwise upward trend. .The fact that we still havent achieved a month below 3C actually cements the argument. In historical terms, 3.0C isnt actually a really cold month. As recently as 18 years ago we had a 1.5C month and 5 years earlier a -1.1C month. As SF has often mentioned, the longer we go without attaining a true cold month, the more unlikely it becomes. The fact that despite a cold winter by recent standards we still cant get the sustained cold to deliver a sub-3.0C month just maintains the idea that potent and prolonged cold is probably beyond us for now.

Even if you look at the period 1896-1928, often cited as a period of milder winters (or indeed 'modern winters' as Mr Datas news cuttings show), still 16 months in the period recorded a sub-3C CET. Indeed, one month was actually November 1915. The fact is, that we are now in the longest period in recorded history that a month has failed to see a CET below the threshold. Its ridiculous to talk of any cooling while this statistic stands.

I must admit that i agree with you, while December was 1.6C below average, which i rate as a pretty large negative anomoly, the fact that we still can't get a very cold winter month indicates to me that this is just a blip in the continuing mild trend.

[reef]

Nope, that is the longest period since 1997

By the way 27th December 1995 - 13th February 1996 CET: 2.8

27th December 1996 - 13th February 1997 CET: 3.2

The problem is, when you pick out arbitary dates like that, it very much is cherry picking. In the case of 1997 it was a potent cold spell followed by a very mild period (indeed February 1st-13th 1997 had a mean of 6.1C).

Essentially all you are doing is showing that this winter has seen prolonged cool weather with very little prolonged mild to cause a correction. In using calendar months you have a set time period which allows comparison to the past without bias.

To myself, it seems that as the climate warms, the range of monthly values we record ever narrows. Being in the northern hemisphere at 50-60N its never going to get very warm in winter. That is why the record mild February for example still lies back in 1779. What we do find though is that the coldest months recorded, get ever higher. The same can be said for the annual CET aswell. While the apparent baseline now seems to be in the 9.5-10.0C range, the upper level still hasnt breached 11.0C. We tend to find a clustering around the 10.5C mark. In the past, you could occasionally record an >10.5C year - which is not too far from the record now, but you also had months much lower, such as 8.74C in 1986.

Edited February 18, 2009 by reef

[Nick L]

Well the fact that we have got a 3.0c month shows that it is very possible to get a sub 3c. It's only 0.1c! I am just glad that we have a below average winter, as CET alone will not prove/disprove any warming.

[kold weather]

Exactly 3C, so still not quite sub 3C but very close, close enough to suggest its still more then possible to achieve I suspect.

[Weather-history]

The problem is, when you pick out arbitary dates like that, it very much is cherry picking. In the case of 1997 it was a potent cold spell followed by a very mild period (indeed February 1st-13th 1997 had a mean of 6.1C).

Essentially all you are doing is showing that this winter has seen prolonged cool weather with very little prolonged mild to cause a correction. In using calendar months you have a set time period which allows comparison to the past without bias.

.

I see what you are saying but however I was comparing a set time period ie 27th December - 13th February 2009 . I wasn't chopping and changing the goal posts, the goal posts were set at those dates. It sort of sinks your point. The only difference is that with a calendar month the goal posts are 28, 29 30 or 31 days apart and in this case the goal posts are 77 days apart.

What a calendar month does is that it makes it easier to make such comparisons easier.

I also don't entirely agree with you about the prolonged cool. 27th December - 10th January CET was -0.2 is not exactly what I would call cool.

So there had to be some correction to this.

One point of interest is that we were within a day of having a sub 3C month

The period 31st December- 30th January CET was 2.8

Edited February 18, 2009 by Mr_Data

[damianslaw]

Oh well only 0.1 degrees above my guess.

[Snowyowl9]

The problem is, when you pick out arbitary dates like that, it very much is cherry picking. In the case of 1997 it was a potent cold spell followed by a very mild period (indeed February 1st-13th 1997 had a mean of 6.1C).

Essentially all you are doing is showing that this winter has seen prolonged cool weather with very little prolonged mild to cause a correction. In using calendar months you have a set time period which allows comparison to the past without bias.

The cold spell didn`t last quite long enough until the 11th,otherwise it would`ve been lower,still now January has come in the coldest for 12 years so it certainly a far cry from 6.6 or 7c from the last 2 years,even 2004 which was 4.3c

Just think of this winter being like 1964/65.

December 3.6c.

January 3.3c

February 3.1c

I can see feb getting upto 3.5c to 4c now though looking at the latest eventful HP charts. :winky:

Average max for Jan here 4.0c

Ave feb max upto today also 4.0c

Edited February 18, 2009 by Snowyowl9

[J10]

I can now finally issue the figures based on the CET of 3.0c.

Well done to mike Meehan, Bobd29 and Rollo for getting the figures spot on.

Overall mountain shadow leads from stormforce10 and mike Meehan sharing 2nd place.

[Snowly does it]

Coldest month of the century on the back of the coldest month versus its own 30 year (71-00) mean of the century

Not too shabby.

Not sub 3, but evidence that sub 3 is still within reach.

A good and cold winter's month.

[❄️❄️❄️❄️❄️❄️❄️❄️❄️]

Wow didn't realise i went for 3.1C, only 0.1C out! And 3C is a pretty cold winter in comparison to the past few years at least!

[BLAST FROM THE PAST]

One point of interest is that we were within a day of having a sub 3C month

The period 31st December- 30th January CET was 2.8

And that makes the can't get sub 3c argument because we have warmed too much utterly ridiculous.

BFTP

[Nick L]

And that makes the can't get sub 3c argument because we have warmed too much utterly ridiculous.

BFTP

And yet aren't some people still arguing this?!

[Stratos Ferric]

And yet aren't some people still arguing this?!

And even more remarkable, for all the fact that those who would rather it weren't true continue to protest, the record book says it hasn't happened.

The facts are stark, and this winter makes abundently clear the issue: to get a calendar month (and THAT IS what goes in the record books I'm afraid) sub 3C requires four and more weeks of sustained and unbroken cold, or else intense cold to compenstae for any less cold conditions.

People can blather on all they like, I say it every year, and have been doing for several now. It simply doesn't happen any more, and with each year that passes with the situation not having been challenged, it becomes less likely - unless and until the local impact of GW ceases. Since there's no hard evidence for the latter at present I can't see an argument.

I live in hope (though I'm not holding my breath) that one day one of the people of the "I quite agree" set will actually stop just writing easy words that, so far as I can evidence are based on no more than personal preference, and will actually produced a fact based argument to show that a sub 3C month might happen. Claiming that we've averaged less than 3C for a longer period doesn't make a compelling case: if it did then perhaps someone will explain why it has NOT converted to a 3C calendar month.

Coldest month of the century on the back of the coldest month versus its own 30 year (71-00) mean of the century

Not too shabby.

Not sub 3, but evidence that sub 3 is still within reach.

A good and cold winter's month.

Or perhaps, like Benjamin Button applied to the weather, what it shows is that it is now tantalisingly out of reach? I really think it needs to happen in the next 2-3 years, otherwise all we'll be left with is the hope for an occasional extraordinary happening.

[Snowly does it]

Or perhaps, like Benjamin Button applied to the weather, what it shows is that it is now tantalisingly out of reach? I really think it needs to happen in the next 2-3 years, otherwise all we'll be left with is the hope for an occasional extraordinary happening.

It shows no such thing. Unless we assume January is 'as cold as it can get' - which given that a one day displaced period of 31 December to 30 January runs in at 2.8 - it clearly isn't.

Winter is allowed to try again next year - its not like you get close and thats that.

It just gets harder with time and warming. Clearly though, this winter shows it IS within reach - the key thing being it hasn't been grabbed even though its sitting right there. It might never be reached. iot might happen all 3 winter months next year, it mgit happen in March. it might not.

December was 1.6 below the 71-00 mean - winter can produce an anomoly of -1.6 to the 30 year mean

Thats 2.6 for Jan/Feb.

That aside, iIs there really any fundamental difference between the 3 of Jan 2009 and the 2.9 it would have been if any 1 day had lost a mere 0.75 degrees?

I say Jan 2009 is no more as cold as it can get than Winter 05-06 was the coldest a even larger teapot can be or 10 a barrier under which we will not pass again annually.

[Yeti]

And even more remarkable, for all the fact that those who would rather it weren't true continue to protest, the record book says it hasn't happened.

That much is true.

The facts are stark, and this winter makes abundently clear the issue: to get a calendar month (and THAT IS what goes in the record books I'm afraid) sub 3C requires four and more weeks of sustained and unbroken cold, or else intense cold to compenstae for any less cold conditions.

People can blather on all they like, I say it every year, and have been doing for several now. It simply doesn't happen any more, and with each year that passes with the situation not having been challenged, it becomes less likely - unless and until the local impact of GW ceases. Since there's no hard evidence for the latter at present I can't see an argument.

I live in hope (though I'm not holding my breath) that one day one of the people of the "I quite agree" set will actually stop just writing easy words that, so far as I can evidence are based on no more than personal preference, and will actually produced a fact based argument to show that a sub 3C month might happen. Claiming that we've averaged less than 3C for a longer period doesn't make a compelling case: if it did then perhaps someone will explain why it has NOT converted to a 3C calendar month.

So 30th of December to 30th of January gives us a CET of 2.8c. That's just one day from an actual calendar month! Whilst I completely agree that we are warming and it gets more and more difficult over time, the fact that we are capable of getting a 31 day period below 3c (and we just have) shows that we are perfectly capable of getting a calendar month with the same result, end of. It is completely impossible to argue otherwise - if January had started a day earlier, we would have had it; next year, or in however many years, such a cold spell may and could happen a day later (or equivalent) and give us an actual sub 3 month.

Or perhaps, like Benjamin Button applied to the weather, what it shows is that it is now tantalisingly out of reach? I really think it needs to happen in the next 2-3 years, otherwise all we'll be left with is the hope for an occasional extraordinary happening.

Most definitely not, as shown above. If we can get a 31 day period sub 3, we can get a calendar month sub 3.

Of course, as we warm, overall the chances of sub 3 decrease (although not year on year, more over a 10 year-or-so basis). However, this winter has shown it is still possible, and it would foolish, frankly, to argue otherwise. We have come as close as it is possible to get to having a sub 3 month (missing out by one day!).

If you're driving from point A to point C via point B, and your car breaks down between A and B, you can't say that it will never happen between B and C, can you?

[Stratos Ferric]

I run a lot, and I am getting older. Many people run, and the fact that running, like weather, lends itself to impericism, allows a lot of detailed statistical analysis to be carried out. One truism, absolutely undeniable, is that as we age we slow - beyond our mid to late twenties - for any given level of fitness. Not to say that I can't run faster next year than I did this, but to do so there would have to be potential left in my tank for my age. I would love to run 6' miles for a 10k race: I have done it for 5 miles, and it would be tempting to extrapolate from there to 6.21, but would I have run the extra 20% as quickly - probably not.

Yes, this year's 31 days does indeed suggest that a calendar month could land sub 3C, but my argument is predicated on a BELIEF that we are now teetering at the point where it's hard to achieve in a favourable year; favourable years don't seem to come along very often. SM is right, and I have already said the same thing, maybe the weather will try again next year, or the year after, and perhaps it might succeed. But what IF we wait another fiftenn years, or twenty three years, for a Hale winter; and if in the meantime we warm as much as we have since 1986?

However, like it or not, in a warming climate, all other things being equal, there comes a time when certain low end benchmarks become so improbable as to be not worth waiting or hoping for.

If I train really hard this year I might get down to 37'12" or so required for the 6' mile equivalent, but if I don't do it this year, irrespective of how close I come, it is possible that next year it might be beyond me. A warming climate with respect to cold weather is rather like an aging body with respect to running speed. Your arguments (Yeti and SM) would be absolutely irrefutable IF we were thirty years back in time, and the climate was not obviously warming, BUT it is warming - whatever the variation in weather, and because we are warming certain outer limits (e.g. the ten year return event, the fifty year return event, the 100 year return event) all move in the same direction as the central trend. In purely statistical terms there comes a point when "nearly" no longer means it might still happen.

(Actually, the discussion about 3C might fog the issue for many people because it "feels" too warm to be emotionally or rationally acceptable: so what say 1C? I doubt anyone on here would argue strongly that a 1C month is still possible, and none of the gerrymandering of the numbers that has been used to make a case for 3C would come remortely close to creating 1C for a 31 day period this year. We are currently in a run of 22 years without a sub 1C month: this has been beaten once in CET history, from 1717-39, a run of 23 years; but that sequence included 7 sub 2 months. The current sequence includes just one, and that was 18 years ago. If we're not careful we'll be arguing that freezing months are still possible, and from there we soon reach a point where mathematically we can no longer argue that the climate has warmed. The fact is that, excluding freak events, there are always bounds within which weather falls for the climate; if the climate changes then the ipso facto the weather moves with it).

It might seem a silly analogy, but actually it fits well. Say a train operates from A to B twice a day, then the service gets reduced to once a day, then every other day, then once a week, then once a month, then once a year, then once a decade...and so on. Eventually the span between a train arriving is longer than my life expectancy, and the wait for a train - if I don't know the timetable, only the frequency - becomes futile.

The point is very simple. When the mean of what is otherwise an almost normally distributed pattern of data starts to increase, the upper and lower limits of the distribution must move in sympathy, and by increments the absolute limits into which all data points fall will also, therefore, move. Within that movement there will be the first time that some upper mark is reached, and the last time that some lower point is hit. The problem is, one never knows the last time something has happened for sure, and the incidence of an outcome close to an assumed limit might well suggest that that limit can be breached, but to argue that it MUST do is incorrect. The fact remains, 3C in a calendar month might still be behind us.

Edited February 21, 2009 by Stratos Ferric

[Yeti]

I run a lot, and I am getting older. Many people run, and the fact that running, like weather, lends itself to impericism, allows a lot of detailed statistical analysis to be carried out. One truism, absolutely undeniable, is that as we age we slow - beyond our mid to late twenties - for any given level of fitness. Not to say that I can't run faster next year than I did this, but to do so there would have to be potential left in my tank for my age. I would love to run 6' miles for a 10k race: I have done it for 5 miles, and it would be tempting to extrapolate from there to 6.21, but would I have run the extra 20% as quickly - probably not.

Firstly, don't be so harsh on yourself! Those times aren't much slower than what I can get and I'm 18!

Yes, this year's 31 days does indeed suggest that a calendar month could land sub 3C, but my argument is predicated on a BELIEF that we are now teetering at the point where it's hard to achieve in a favourable year; favourable years don't seem to come along very often. SM is right, and I have already said the same thing, maybe the weather will try again next year, or the year after, and perhaps it might succeed. But what IF we wait another fiftenn years, or twenty three years, for a Hale winter; and if in the meantime we warm as much as we have since 1986?

However, like it or not, in a warming climate, all other things being equal, there comes a time when certain low end benchmarks become so improbable as to be not worth waiting or hoping for.

If I train really hard this year I might get down to 37'12" or so required for the 6' mile equivalent, but if I don't do it this year, irrespective of how close I come, it is possible that next year it might be beyond me. A warming climate with respect to cold weather is rather like an aging body with respect to running speed. Your arguments (Yeti and SM) would be absolutely irrefutable IF we were thirty years back in time, and the climate was not obviously warming, BUT it is warming - whatever the variation in weather, and because we are warming certain outer limits (e.g. the ten year return event, the fifty year return event, the 100 year return event) all move in the same direction as the central trend. In purely statistical terms there comes a point when "nearly" no longer means it might still happen.

That's rather beside the point, though, because warming takes place over a long period of time. The fact that we can achieve 31 days at 2.8c shows that we can get a calendar month below 3c, despite recent warming, because we do not warm year-on-year (as you know) and this year has proven that sub 3c is still possible. Far less likely, but still possible - which at the end of the day, is the only point I ever made. Remember my analogy of driving from A to C via B?

(Actually, the discussion about 3C might fog the issue for many people because it "feels" too warm to be emotionally or rationally acceptable: so what say 1C? I doubt anyone on here would argue strongly that a 1C month is still possible, and none of the gerrymandering of the numbers that has been used to make a case for 3C would come remortely close to creating 1C for a 31 day period this year. We are currently in a run of 22 years without a sub 1C month: this has been beaten once in CET history, from 1717-39, a run of 23 years; but that sequence included 7 sub 2 months. The current sequence includes just one, and that was 18 years ago. If we're not careful we'll be arguing that freezing months are still possible, and from there we soon reach a point where mathematically we can no longer argue that the climate has warmed. The fact is that, excluding freak events, there are always bounds within which weather falls for the climate; if the climate changes then the ipso facto the weather moves with it).

That is a good point, Stratos, and one which I have made a few times on here. What is the real obsession with sub 3c anyway? Even if we got a month at, say, 2.6c (which I would argue is still, with a bit of luck, just within reach) where would that leave us? A full 3c from Feb 86 and a long way from even 91 (hardly the coldest of months). Even if we got sub 3, it wouldn't change my opinion at all wrt recent warming, as it would all lie within the bounds of natural warming. I gave an anology of the incoming tide in the climate thread - you can stand on the beach and see the waves rising and falling, but you know that the overall trend is up. Sadly, I bear more than a slight suspicion that a few on here would take a sub 3 month as a refutation of the entire AGW hypothesis, and at least of its direct effect on the British Isles.

It might seem a silly analogy, but actually it fits well. Say a train operates from A to B twice a day, then the service gets reduced to once a day, then every other day, then once a week, then once a month, then once a year, then once a decade...and so on. Eventually the span between a train arriving is longer than my life expectancy, and the wait for a train - if I don't know the timetable, only the frequency - becomes futile.

Yep... with every five years, at least, that pass, the overall trend rises... and we stand less and less chance of seeing the train arrive. Again, using the analogy of the tide, the chance of a receding wave reaching "that almost-smothered pebble" decreases (until at some point, it is permanently submerged, although I don't believe we are at that stage yet).

The point is very simple. When the mean of what is otherwise an almost normally distributed pattern of data starts to increase, the upper and lower limits of the distribution must move in sympathy, and by increments the absolute limits into which all data points fall will also, therefore, move. Within that movement there will be the first time that some upper mark is reached, and the last time that some lower point is hit. The problem is, one never knows the last time something has happened for sure, and the incidence of an outcome close to an assumed limit might well suggest that that limit can be breached, but to argue that it MUST do is incorrect. The fact remains, 3C in a calendar month might still be behind us.

It might, but then again I doubt it. The evidence we have tells us that it is - the question is whether we can achieve another 31 day run (this perhaps undoubtedly) WITHIN the boundaries of one calendar month (this relies on an element of chance). It is still possible, but this winter has shown that it's now not just down to a case of getting the right temperatures - we now have to get them at exactly the right time to produce the goods.

Another way of looking at it, is that if we achieved a 31 day period of sub 2c, there could be little doubt that wherever the calendar boundaries were placed, a sub 3c month would be returned. Sadly, I do suspect that sub 2c is well and truly behind us (and before I am trampled on, it is a *suspicion*). In other words, the correct timing of cold spells is now perhaps becoming a necessity in terms of achieving sub 3...

Regards

David

[Thundery wintry showers]

There's quite a lot of abstract stuff in this argument. What we're looking at is a situation where with each decade that passes, the probability of getting a sub CET month in a given winter is steadily reducing. The question is, has that probability got negligibly small yet?

I honestly don't think it has. Yes, picking out various 31 day periods can be seen as cherry-picking, but as far as I'm concerned, if we are getting a fair number of 31-day periods where the CET is considerably below 3C, it suggests that the probability of getting such a period coinciding with a calendar month is far from negligibly small. This is especially true when we consider that we've had >70 day periods with an average below 3C.

It is fair, though, to say that barring a switch in the global climate, there will come a point in the future when that probability does become negligibly small. If we do not see a sub 3C CET between now and then, then chances are that we won't see one again in our lifetimes.

In my view the "floor" for a winter CET over a calendar month is still below 2C, let alone 3C- taking the outturn of 3C over the period 1-23 March 2006 as an illustration. However, sub 2C has already become a very long shot, and sub 1C would probably require an anomaly, synoptically speaking, on the scale of 1947 and 1963. And I think the days when we could realistically achieve a sub-zero month are gone.

Time will tell over the coming years, but it will certainly be a cause for concern if this "Hale winter" has produced the "modern" equivalent of a January 1940, January 1963 or February 1986. Certainly, synoptically speaking this winter has been different, but then again, we haven't had the extent of northern blocking or deep cold airmasses that we got in the aforementioned three months. The next couple of winters will be well worth keeping an eye on...