Frequent cold records being set

[Thundery wintry showers]

Re. a point in another thread, in which cold/snow records are being posted. The fact that cold records are still being set does not prove that the globe isn't warming, just as the coldest temperature of the 1989/90 winter widely being set in early April didn't prove that April isn't, on average, warmer than February or March. Put it this way, if you get cold records falling from time to time, by a margin of more than 0.5C, and we get 0.5C warming, then all things being equal, we will continue to get cold records.

What needs to be put to the test is whether or not we are getting more warm records being set than cold records. We also need to be consistent with the time spans involved, it's no good quoting records from stations where records started in 1990, and treating them as if they carry as much weight as with records dating back to 1890. So far I haven't seen any evidence presented either way on that.

However, there are two stonewall facts as far as global warmth is concerned:

1. The globe, as a whole, has warmed by about 0.5C over the last 50 years

2. On the other hand, January 2008 had a global temperature close to the 100-year mean.

Thus, it may well be that we saw at least as many cold records as warm ones going in January, as this would reflect the somewhat cooler global temperature than we've been used to recently. But one month doesn't constitute a long-term trend; we need to see how the next few months develop.

[PersianPaladin]

Its already been said on here...the current downwardly trending global anamolies are a mere blip when viewed in the context of the 100 year representative sample.

[Guest mycroft]

Its already been said on here...the current downwardly trending global anamolies are a mere blip when viewed in the context of the 100 year representative sample.

Bet the Viking settlers thought that in Greenland in the 11th/12th century :huh:

[Stratos Ferric]

Bet the Viking settlers thought that in Greenland in the 11th/12th century :huh:

Bet they hadn't got a clue. Thermometers didn't come along for another few hundred years.

[Guest mycroft]

Very true but they had canny noses in them days :huh: :And after a few seasons of watching the ice advance crop failure. colder and colder winters and summers.Its something we "modern" humans have lost.

Edited February 19, 2008 by mycroft

[laserguy]

1. The globe, as a whole, has warmed by about 0.5C over the last 50 years

And therein lies the problem. Everyone quotes different figures. Sincere apologies if I'm mistaken but I do believe 'twas you TWS who reported recently that the warming amounted to 0.5F over 100 years. It seems that no-one really knows for sure,perhaps there's been no warming at all,or maybe a cooling over that time. I'm not seriously suggesting that's the case,just pointing out that the common man has absolutely no way of knowing, and judging by the discrepancy between 'authorities' they don't either!

As far as those Greenlanders were concerned,SF and Mycroft,we do have thermometers plus technology beyond their ken and we wouldn't have noticed a thing either without them! Which brings me back to my point of a while ago re. examining the minutiae and making mountains out of molehills. Is 0.5F (or thereabouts) such a big deal over 100 ish years? I think not,that's assuming it's correct. Slightly OT here and very rough but let's assume that 50% of that has been caused by anthro CO2;that makes it responsible for around 0.25F increase in 100 years. Is this really cause for end of world,planet busting scenarios? Nope,compared to what's gone before without us lot around it's precisely nothing.

[cheeky_monkey]

ill think you will find everybody has quoted 0.5c not 0.5f

[Bobby]

It's a ridiculous argument. The only way, and absolutely no other way, to say if the climate is cooling or warming is looking at a long term global average temperature records. That is the ONLY way. It's the same for warming too - an exceptional heatwave does not prove warming. Neither does a record breaking scorching summer. They all prove nothing.

Everyone needs to realise this. It is bad science, bad logic and bad statistics to to say that we may be warming just because of a heatwave in France or be cooling due to a potent cold snap in Canada.

As I've said before, if the next 5 years are cooler than the last 5 years, now that would be interesting and may suggest something. Next 10 years cooler than the last 10 years would suggest something even more concrete. Let's wait for that before anyone even suggests we are cooling. Or continuing to warm indeed.

[Thundery wintry showers]

And therein lies the problem. Everyone quotes different figures. Sincere apologies if I'm mistaken but I do believe 'twas you TWS who reported recently that the warming amounted to 0.5F over 100 years.

I don't ever remember saying 0.5F- sounds like that would be from some US study because they continue to quote temperatures in F rather than C.

I might quote 0.5F (or more likely the equivalent 0.3C) over the last 20 years perhaps.

[laserguy]

I don't ever remember saying 0.5F- sounds like that would be from some US study because they continue to quote temperatures in F rather than C.

I might quote 0.5F (or more likely the equivalent 0.3C) over the last 20 years perhaps.

Profuse apologies TWS,but I did say I wasn't sure! I do stick to the point though that there are numerous figures being bandied about. One only has to look through this forum to see the variance quoted by contributors,which shows that sources vary in their estimates.

[wysiwyg]

I am fully in agreement with those who believe that cold/warm incidences, be they records or just notable, are not robust enough to use as evidence that the sign of global temperature is changing in either direction. I feel that it was unfair to comment in the other thread started as that was set up in direct response to a request for evidence that cold records were being set. (Inevitable though that people would comment in such a thread)

What is worrying though is that these records do represent something amiss with the climate in general. It seems illogical that a warming world should cause cold events on the scale seen in recent weeks but we all know very well how complex the atmosphere and climate is in the short term. To me these records being set represent nothing more than an increased amount of agitation in the atmospheric circulation leading to either unusual synoptics or normal synoptics with higher than usual energy. I don't know which - perhaps someone else can add this dimension to the argument.

I think it is unwise to jump on a series of individual events to signal a cooling trend. We mistakenly called for a cooling trend in the 70s which turned out to be a levelling followed by further warming which lead to a sea change in outlook wrt climate change.

With regards to the Vikings in Greenland - I bet they didn't just pack up and leave after one poor harvest caused by a cold year either. They didn't have thermometers but they knew that after a few cold years with poor crops it was time to move somewhere warmer. Nor did the glaciers appear on their doorsteps overnight but they will have been watching them and worked out pretty quickly that they were advancing and that they posed a threat.

Wysi :o

[cheeky_monkey]

would global dimming be a factor here?..western and northern europe is pretty much clear from atmospheric pollution in comparison to 40/50 years ago result warmer winters and summers whilst asias and chinas is on the increase? could that explain cold outbreaks in these areas. while we get none?

Edited February 19, 2008 by cheeky_monkey

[wysiwyg]

would global dimming be a factor here?..western and northern europe is pretty much clear from atmospheric pollution in comparison to 40/50 years ago result warmer winters and summers whilst asias and chinas is on the increase? could that explain cold outbreaks in these areas. while we get none?

I think global dimming may be a factor but from my understanding of it the effects are not instantanous enough to directly cause these sudden and record breaking events. Even the IPCC admits that it is one of the least understood mechanisms in the atmosphere (i.e. cloud formation as a result of aerosol and particulate emissions) IMO it's just another of the complexities of the climate that we need to understand better before we can link it with all the other factors that directly or indirectly affect our climate in the medium to long term.

[VillagePlank]

The only way, and absolutely no other way, to say if the climate is cooling or warming is looking at a long term global average temperature records.

In my opinion, this, in and of itself, is a nonsense.

If the UK mean increased by 2C and France decreased by 2C, and we pretended that that was the globe, the UK would be like a desert, and France would be like the arctic (a bit exaggerated on both counts) The global mean would show no change.

Edited February 19, 2008 by VillagePlank

[Bobby]

In my opinion, this, in and of itself, is a nonsense.

If the UK mean increased by 2C and France decreased by 2C, and we pretended that that was the globe, the UK would be like a desert, and France would be like the arctic (a bit exaggerated on both counts) The global mean would show no change.

We're talking about the Earth as a whole warming or cooling. The ONLY way determine that is long term global average temperature records. I really don't understand the point of that example.

How it's nonsense I don't understand.

Edited February 19, 2008 by Magpie

[VillagePlank]

We're talking about the Earth as a whole warming or cooling. The ONLY way determine that is long term global average temperature records. I really don't understand the point of that example.

How it's nonsense I don't understand.

I am saying that a global average is meaningless and therefore nonsense; the example I gave demonstrated that despite extreme climate shifts it wouldn't even register on the 'global' mean.

In the same manner you can use exactly the same arithmetic technique to show, over time, a significant event in time period 1, followed by, say, a normalisation event in time period 2.

1. UK +2C, France -2C GMA=0

2. UK 0C, France +1C GMA=+1

Here, at 1, a huge climatic shift has happened: it is not represented in the global mean average. The UK retains this extreme heating up in 2, and France recovers from it's 'Little Ice Age' showing an effective warming. What does the GMA show? 0 and then 1. That is NOT representative of what is actually going on.

EDIT: This is a warming example (there are 3C extra lurking around) the GMA should be showing aggregately a 3C rise (but it isn't because the signal is masked by Frances excessive, but brief cooling) The same works the other way around for cooling.

Edited February 19, 2008 by VillagePlank

[Bobby]

We're not talking about climate shifts though, just the average temp of the Earth - the amount of energy present in the atmosphere. The average temperature of the Earth rising is exactly that, it doesn't claim to measure anything else.

Of course, the Northern hemisphere could warm 5c and the southern could cool 5c and that wouldn't register at all. It's a different subject though, global warming just is about average global temperatures. It's not nonsense because it is what it is.

[VillagePlank]

We're not talking about climate shifts though, just the average temp of the Earth - the amount of energy present in the atmosphere. The average temperature of the Earth rising is exactly that, it doesn't claim to measure anything else.

Of course, the Northern hemisphere could warm 5c and the southern could cool 5c and that wouldn't register at all. It's a different subject though, global warming just is about average global temperatures. It's not nonsense because it is what it is.

It's not a different subject though - the hopes and dreams of humankind are pinned against this sort of statistic. I believe it doesn't actually mean anything more than the averaging of numbers in a telephone book. I think that it doesn't actually tell us anything.

Edited February 19, 2008 by VillagePlank

[wysiwyg]

We're not talking about climate shifts though, just the average temp of the Earth - the amount of energy present in the atmosphere. The average temperature of the Earth rising is exactly that, it doesn't claim to measure anything else.

Of course, the Northern hemisphere could warm 5c and the southern could cool 5c and that wouldn't register at all. It's a different subject though, global warming just is about average global temperatures. It's not nonsense because it is what it is.

Agreed and in a proper statistical analysis outliers would be taken into account. We could argue all day about statistics but we have to reach a point where we accept one or other methods of quantifying climate variability. The mean global value is the best 'headline' value that we have but no serious 'scientist' (including us lay-scientists ) is going to accept either the mean value on its own or isolated extreme outliers without proper statistical coroberation.

[Bobby]

It's not a different subject though - the hopes and dreams of humankind are pinned against this sort of statistic. I believe it doesn't actually mean anything more than the averaging of numbers in a telephone book. I think that it doesn't actually tell us anything.

That's true to an extent but it is the average warming, the more energy in the atmosphere, that will drive the climate shifts, that will drive the volatility. The global average temperature increasing just measures the change that is underway, and the more the average temperature of the Earth changes as a whole, then the greater the local volatality.

[VillagePlank]

... in a proper statistical analysis outliers would be taken into account ...

But that's the point - the average, by it's definition includes the outliers, and they skew it beyond usefulness. Actually, they have the ability to skew it beyond usefulness - whether or not they actually do would mean that you'd need to peform analysis on every contributing station agaisnt every other contributing station. Yuk. But that risk is still a reality (the risk, I couldn't possibly confirm/deny the actual)

Edited February 19, 2008 by VillagePlank

[wysiwyg]

It's not a different subject though - the hopes and dreams of humankind are pinned against this sort of statistic. I believe it doesn't actually mean anything more than the averaging of numbers in a telephone book. I think that it doesn't actually tell us anything.

The telephone book analogy has been done before - imho it's relevant to statistics but not to the climate change issue. There is no correlation between phone numbers and anything afaik!

During the last ice age the globally averaged climate would have been far cooler than it is now but extremes of climate would have occurred on a day-to-day basis. Can we really ignore mean global temperature as one (of many) indicators of climate change? I can see your point wrt pinning human futures on a statistic but I think you might just be oversimplifying the issue a tad. Mean temperature trends are the best measure of climate change that we have but, as I previously stated, i don't think anyone is realistically taking one single statistic in isolation and plotting the future of humanity from it.

[VillagePlank]

The telephone book analogy has been done before - imho it's relevant to statistics but not to the climate change issue. There is no correlation between phone numbers and anything afaik!

But we don't understand the correlation between the global mean and local means - so what is the global mean correlated, if anything, too? Do we have an averaged CO2 measurement? (I presume it takes time for CO2 to mix in the atmosphere, and, at least, it's not instant?)

Indeed, compared to the global mean, the CET is racing away, they certainly aren't well correlated except, I guess, in that both are going upwards(ish)

Edited February 19, 2008 by VillagePlank

[wysiwyg]

But that's the point - the average, by it's definition includes the outliers, and they skew it beyond usefulness. Actually, they have the ability to skew it beyond usefulness - whether or not they actually do would mean that you'd need to peform analysis on every contributing station agaisnt every other contributing station. Yuk. But that risk is still a reality (the risk, I couldn't possibly confirm/deny the actual)

I think there is probably a fair bit of work goes into doing just what you suggest i.e. removal or correction of the outliers to give a more accurate and representitive mean. That in itself implies that we could massage the figures to show anything we like in theory but I think that is unlikely here as we are talking about scientists that actually do this type of analysis because they want the truth and accept that the 'modified' data will be peer reviewed for incosistencies and errors. The fact that the 'headline' figures get spun into all sorts of potential scenarios is quite a different matter!

[VillagePlank]

I think there is probably a fair bit of work goes into doing just what you suggest i.e. removal or correction of the outliers to give a more accurate and representitive mean. That in itself implies that we could massage the figures to show anything we like in theory but I think that is unlikely here as we are talking about scientists that actually do this type of analysis because they want the truth and accept that the 'modified' data will be peer reviewed for incosistencies and errors. The fact that the 'headline' figures get spun into all sorts of potential scenarios is quite a different matter!

I fully accept what you are saying

But .... I can't accept that notion that if the UK cooled by some 2C and then France heated up by 2C the climatic disasters that would entail in those countries would be catastrophic (I think) The 'global mean' between the two, though, would not even register a blip.

Perhaps it's just me, huh?

Edited February 19, 2008 by VillagePlank