Excerpt from Bishop Hill (plus a cartoon from Josh) showing that the claim of a statistically significant temperature rise can’t be supported, and the Met office is ducking parliamentary questions: (h/t Randy Hughes)
Met Office admits claims of significant temperature rise untenable
This is a guest post by Doug Keenan.
It has been widely claimed that the increase in global temperatures since the late 1800s is too large to be reasonably attributed to natural random variation. Moreover, that claim is arguably the biggest reason for concern about global warming. The basis for the claim has recently been discussed in the UK Parliament. It turns out that the claim has no basis, and scientists at the Met Office have been trying to cover that up.
The Parliamentary Question that started this was put by Lord Donoughue on 8 November 2012. The Question is as follows.
To ask Her Majesty’s Government … whether they consider a rise in global temperature of 0.8 degrees Celsius since 1880 to be significant. [HL3050]
The Answer claimed that “the temperature rise since about 1880 is statistically significant”. This means that the temperature rise could not be reasonably attributed to natural random variation — i.e. global warming is real.
…
The issue here is the claim that “the temperature rise since about 1880 is statistically significant”, which was made by the Met Office in response to the original Question (HL3050). The basis for that claim has now been effectively acknowledged to be untenable. Possibly there is some other basis for the claim, but that seems extremely implausible: the claim does not seem to have any valid basis.
Go read the entire essay here: http://www.bishop-hill.net/blog/2013/5/27/met-office-admits-claims-of-significant-temperature-rise-unt.html
Josh has a go at them:
Does this mean when someone asks us “has the earth warmed over the last century” we can say “NO!”
Scott Basinger says:
May 28, 2013 at 9:20 am
Nick Stokes says:
May 27, 2013 at 11:48 am
“I wish posts like this would simply state their argument. There’s a big bold heading saying:
“Met Office admits claims of significant temperature rise untenable”
…
And if you follow the link to BH, there’s a long ramble from Doug Keenan on his opinions about the meaning of statistical significance, and confused discussion in the House of Lords.”
He is a smart guy and he does have things to contribute. But at times he cannot help himself.
You are right, NickStokes isn’t a troll, he is a racehorse.
Scott Scarborough says:
May 28, 2013 at 10:35 am
Does this mean when someone asks us “has the earth warmed over the last century” we can say “NO!”
====================
pretty much
The claim is that the earth has warmed 1/2 a degree…
…when there was a 2 degree spread on what normal is
If you move the normal line up…just 1/2 degree….etc
Nick Stokes says:
May 28, 2013 at 6:07 am
climatereason says: May 28, 2013 at 4:33 am
“Its ok, you can relax. It seems that Melbourne did not experience its 4th warmest April ever (in its very short record)”
Tony, I believe it did. I think you are looking at the list of which days were warmest in the month. Anyway, max temps were 1C above normal, min 1.5 above. Australia had its 5th warmest April.”
According to this
http://www.accuweather.com/en/au/melbourne/26216/april-weather/26216?monyr=4/1/2013
Melbourne exceeded the historical avg high by 1F on the 8th and 27th, 2F on the 28th. For the rest of the month daily highs were mostly in the 10F to 20+F below hist. avg. Daily lows exceeded HA by 4F on the 13th, 3F on the 26th, 1F on the 27th and 28th. The rest of the month was at or below HA, although not as dramatically as the daily highs. I would never claim Accuweather as a most authoritative source but something seems to be wrong with this picture.
It’s ‘cat amongst the canaries’, Anthony, not pigeons!:] Here’s an amusing bit of hysteria.
[snip – reposting entire news articles from the Guardian is a copyright violation, use an excerpt combined with a link – Anthony]
@ur momisugly ralfellis says: “Academic freedom my *rse.” +1000
http://wattsupwiththat.com/2013/05/27/uh-oh-the-met-office-has-set-the-cat-amongst-the-pigeons/#comment-1319239
GeeJam: ‘WHAT COUNTRY, RIGHT NOW, IN THE WORLD, IS SIGNIFICANTLY WARMER THAN IT NORMALLY IS FOR THIS TIME OF YEAR?’
Well, right now the weather where I live is pretty Arctic, or in our case Antarctic, but New Zealand has been experiencing an anomalously warm Autumn this year.
Everybody says so, and the official figures agree: parts of the country have been more than 1.2 deg C above the April average, and across the country as a whole, temperatures were 0.7 deg C above the 1971-2010 April average.
http://www.niwa.co.nz/sites/default/files/nzcu_may_2013.pdf
I don’t think it’s very surprising, though, that if some parts of the world are colder than normal, other parts will be warmer than normal.
DavidG says: May 28, 2013 at 11:14 am It’s ‘cat amongst the canaries’,
Anthony Watts, being the cat’s wiskers, has it right of course. This post may be the canary in the coal mine for the Met Office though.
DavidG says:
May 28, 2013 at 11:14 am
It’s ‘cat amongst the canaries’, Anthony, not pigeons!:
Among pigeons where I was born.
Dave Wendt says: May 28, 2013 at 11:12 am
“I would never claim Accuweather as a most authoritative source but something seems to be wrong with this picture.”
You’re right. The daily temperatures look right, but the averages are crazy. 84F in early April??? Maybe they are looking ahead.
Here is the correct version. Ave max for April is 20.3C – about 68.5F. And here’s the daily story.
Stephen Wilde – Thanks for the link. I had missed it at the time. I’ve read it and will think about it. Some parts seem to have merit, some seem dubious, but this thread isn’t the place to discuss it. The subject will come up again many times, no doubt.
Agnostic says at May 28, 2013 at 4:24 am…
Spot on. Absolutely correct.
The confusion amongst some (and some who should know better) arises from the false idea that the MET office has admitted that there is now no warming trend. They have not said that. It would be obviously untrue.
They have found that the warming trend is better explained by Keenan’s model than the model they had been using. The model they had been using could not explain the warming without some factor that is outside the known natural variation.
Keenan’s model needs nothing but natural variation to explain the observed warming.
And the MET office admits that Keenan’s model is a better fit.
So if you want to believe that something other than natural variation has occurred and is occurring, well, you may so believe.
But that is a faith position. That is not a scientific viewpoint.
You no longer need to imagine extra factors; CO2 overwhelming the historical feedbacks, the aliens from the Kraken Awakes or anything else that you can sell to Hollywood. It is no longer required.
AGW may be right but it is no longer realistic.
Unless you can show that Keenan’s model does not explain the observed warming by natural variation alone.
William Astley says:
May 27, 2013 at 12:20 pm
I recently noticed the cooling in Antarctica. Earlier I made this comment elsewhere….
goldminor says:
28 May 2013 at 6:32 pm
Yes, but it is a warm cold. The other day I was looking at the NSDIC graph of Antarctica sea ice extent. The graph started from 1979 to the present. This last summers sea ice melt shows close to being a record since 1979 for the least melting in the time frame of the graph. I do not see this being talked about. Plus, in looking at those 34 years, there is a distinct cooling trend that has been building through the entire series, less summer loss with more winter gain. I was arguing with a warmist about the poles and that led me to take a longer look at current info. This also made me wonder ‘Does the South Pole lead the way by cooling first, which is then followed by cooling in the NH years later?’.
“Uh oh, the Met Office has set the cat amongst the pigeons.”
We’ll see. I’m kind of with Tallbloke on this one, almost certain to be ignored by the mainstream news media. Mr. Keenan’s article suggests that at least three people should already have been forced to tender their resignations: Parliamentary Under Secretary of State, Baroness Verma; Met Office Chief Executive Officer, John Hirst; and Met Office Chief Scientist, Julia Slingo. It doesn’t take much to predict that nothing will happen and that these three will continue to do what ever they want regardless of legality for as long as they wish. There doesn’t seem to be any force of accountability with the Met Office at all, too bad for us all, not just in the UK. Crooks far and wide are emboldened by these types of outcomes.
W^3
Nick Stokes:
“Oddly enough, I was there through the summer of 1975. A beautiful warm summer.”
So you admit you like it warm Nick. Glad to hear it – that means you must be rather happy with the tiny amount of warming we’ve had since the end of the 19th century.
BTW I’d like to say that I don’t think Nick is a troll. He’s just polite and persistent. I hate the way any blog, be it alarmist or sceptic, describes anyone they don’t agree with as a ‘troll’. Debate with people from the ‘other side’ is what keeps us constantly enquiring and constantly unearthing the fallacies behind CAGW. Genuine scientific discovery is all about disagreement and debate with those in Camp Consensus.
– – – – – – –
Nick Milner,
Your comment stimulates an overview of what skepticism can be viewed as wrt climate science.
There are skeptics (call them skeptic type #1) who claim certainty in the theory that when CO2 from burning fossil fuels is added to the Earth’s atmosphere then there must be some surface temperature warming on a transient and / or a steady state basis; with these type #1 skeptics there are some who maintain the caveat that all other climate dynamics/factors must remain equal and also there are some others of these type #1 skeptics who do not use that caveat in their position. What makes type #1 skeptics be skeptics is their finding of minor warming from CO2 from burning fossil fuels and / or any warming is beneficial to life (not bad like CAGWists claim).
There are also skeptics (call them skeptic type #2) who maintain there are not to date any statistically determinable climate signal variations of significance on any timescale that preclude a natural explanation of observed climate data.
There are other skeptical positions, of course. Just considering type #1 & #2 skeptics, I think they are not fundamentally inconsistent with each other. One could hold both rationally.
I tend to find the skeptic position #2 reasonably established. However, I do not find skeptic position # 1 reasonably established because it merely presumes without unequivical observational verification that actual warming has been caused on any timescale by CO2 from natural sources or from fossil fuel sources. Therefore I conclude that skeptic #1 position is still untested in reality .
John
I think Nick should definitely be NOT told to go away from this site. These guys are the best evidence of the stupidity of the AGW “theory” which is not working. They only help to support the skeptic case (over time).. Others are Telford, Flannery etc. Unfortunately there all Australian and reflect very poorly on the Australian Higher Education system destroyed by Dawkins in the 80’s
John Whitman says: May 28, 2013 at 3:08 pm
“it merely presumes without unequivical observational verification that actual warming has been caused on any timescale by CO2 from natural sources or from fossil fuel sources.”
I think that is a common but wrong argument. AGW says that burning C will block IR and cause warming of a certain degree. That is based on IR physics etc. If we burn C and see about that amount of warming, then that is consistent with the theory. No better can be asked of it. If it turns out that random variation could have caused the warming, that does not demolish the theory – it’s still true that things are happening as it predicted.
GeeJam says:
May 28, 2013 at 5:13 am
And as for traditional ‘May Blossom’ (Hawthorn), it’s only just coming out – which is unusually late.
“Don’t cast a clout ’til may be out.” Sensitive flower doesn’t like the cold.
I have diffculty with the statement of Richard Telford “The 1 in the ARIMA(3,1,0) is needed because the data are non-stationary – the mean is not constant – the temperature is increasing.”
In my understanding of spatial and time series analysis, it is not correct to state the data are stationary (or non-stationary). Stationarity is an assumption about the data that influences our choice of model. It is perfectly reasonable to have a stationary model that exhibits considerable periods of increasing or decreasing values and such systems are found throughout nature, including earth sciences. Depending on your background this might be described as “persistence” or “temporal dependency”, or some other terminology.
For those who are uncertain of the importance of this, consider a simple periodic system (imagine a noisy sine wave). A noisy sine wave is stationary, in other words the long term average is about zero. Then imagine that you can only observe a short time period of this system (less than one quarter of the period). Then you will see a time series that appears to have a trend, the trend by simple statistics is apparently highly significant, but if you were able to observe a much longer interval it would become evident that the data is simply swinging around a constant long term mean. If the temporal scale of the processes driving climate and temperature are natural but act over longer periods then then available time period of measurements then analysis of that short period will give a spurious significance to the assumption of a non-stationary model.
If you now consider say a 2,000 year temperature reconstruction (such as that by Loehle) and observe a medieval warm period and little ice age, but the temperature on average has not really gone up or down overall, just oscillated around a constant, then it is hard to claim that temperature rise over the last 150 year temperature record is therefore non-stationary and has a staitstically significant trend. This is why in the climategate emails it is so damning to read about “getting rid of the medieval warm period” and hence the absurd effrots to defned the indefensible in the form of the Mann “Hockey Stick”: if you can get rid of the medieval warm period (and the little ice age) then there is little to stop you choosing a non-stationary model and blaming CO2.
If you don’t know all the natural processes, lags and mechanisms driving long term trends such as medieval warm period/little ice age then an argument of AGW cannot be claimed as being “the only explanation” when clearly natural variation is large and the recent warming is within the bounds of what is known currently about historical temperature changes. And the statement that the “data are non-stationary” is putting the cart before the horse. Data are simply measurements – it is models that are stationary or non-stationary.
– – – – – – –
Nick Stokes,
Thanks for your comment.
The scientific dialog is not resolved on the issue. Therefore reasonable people in the community can and are pursuing evidence both pro and con. It is not settled. I do not dispute that incremental CO2 has radiative properties and theoretically therefore may have capability of additional surface heating; what I think is that it is not reasonably established by unequivocal observational verifications that actual heating is caused due to the theory.
That is the way it should be now that the artificially enforced IPCC consensus has eroded sufficiently.
John
ThinkingScientist,
You make way too much sense. You must be in the pay of Big-Kochtopus or something or other.
John Whitman says:
May 28, 2013 at 4:56 pm
———————————
I think that absorption by CO2 of energy radiated off the surface of the earth, which absorbed energy the excited gas molecules then radiate in all directions, is well established. Some of this radiation will travel back down toward the surface. This process delays the convection of the surface-reflected energy back out to space.
I also believe that the heating effect of one, two or three more CO2 molecules (up from three a century ago) per 10,000 molecules of dry air is trivial at best. The effect might be measurable, if not at a high level of statistical significance, in some conditions, such as the dry air of the arctic. But in the tropics, where there might be 400 water vapor molecules per 10,000, it’s possible that the net effect could even be cooling, but more likely any possible warming is simply swamped out.
The human contribution to increased CO2 is also negligible. To paraphrase Dr. Tim Ball, subject of a suit by Mann, “If climate were a car, its engine would be the sun and water vapo(u)r the transmission. CO2 would be at most one wheel, of which one lug nut might be man-made”, or words to that effect. My apologies if the paraphrase be too loose.