Just a little something he threw together
Guest Post by David Middleton
First the breath-taking headlines…
- Scientists Report Faster Warming in Antarctica, New York Times (WUWT commentary)
- West Antarctic Ice Sheet warming twice earlier estimate, BBC
- West Antarctica warming much faster than previously believed, study finds, NBC
- Western Antarctica is warming three times faster than the rest of the world, Grist
Oh noes out the wazzoo!!!
What could possibly have caused such an out-pouring of Mr. Bill impersonations?
Apparently this did…
Central West Antarctica among the most rapidly warming regions on Earth
David H. Bromwich,1, 5 Julien P. Nicolas,5, 1 Andrew J. Monaghan,2 Matthew A. Lazzara,3 Linda M. Keller,4 George A. Weidner4 & Aaron B. Wilson1
Nature Geoscience Year published: (2012) doi:10.1038/ngeo1671
Received02 May 2012 Accepted15 November 2012 Published online23 December 2012
Abstract
There is clear evidence that the West Antarctic Ice Sheet is contributing to sea-level rise. In contrast, West Antarctic temperature changes in recent decades remain uncertain. West Antarctica has probably warmed since the 1950s, but there is disagreement regarding the magnitude, seasonality and spatial extent of this warming. This is primarily because long-term near-surface temperature observations are restricted to Byrd Station in central West Antarctica, a data set with substantial gaps. Here, we present a complete temperature record for Byrd Station, in which observations have been corrected, and gaps have been filled using global reanalysis data and spatial interpolation. The record reveals a linear increase in annual temperature between 1958 and 2010 by 2.4±1.2 °C, establishing central West Antarctica as one of the fastest-warming regions globally.
[…]
The manufactured “record reveals a linear increase in annual temperature between 1958 and 2010 by 2.4±1.2 °C.” That’s a 50% margin of error on the reconstruction that supposedly corrected the recording errors.
I haven’t purchased access to the paper (nor do I intend to); however, the freely available supplementary information includes a graph of their reconstructed temperature record for Byrd Station. It looks very similar to the NASA-GISS graph that doesn’t show any significant recent warming trend.
The NASA-GISS data (GHCN & SCAR) for Byrd Station are in two segments: 1957-1975 and 1980-2012. The 1957-1975 series depicts a moderately significant (R² = 0.19) warming trend of about 1.0 °C per decade. The post-1980 series depicts a statistically insignificant (R² = 0.01) trend of 0.3 °C per decade.
Bromwich et al., 2012 get their 2.4 °C of warming from 1958-2010 (0.4 °C per decade) by stitching together the fragmented data sets. If I just combine the two NASA-GISS series, I get a trend of about 0.4 °C per decade…
But, almost all of that warming took place before 1988. And Byrd Station has seen no warming (actually a slight cooling) since 1991.
Furthermore, the corrected temperature record of Bromwich et al., 2012 appears to actually depict more cooling since 1991 than the uncorrected data…
I wish that was true; but it isn’t.
The instrumental record (HadCRUT) captures about 160 years’ worth of data, all of which is on the up-slope of the millennial scale cycle. It should appear to have a linear secular trend, just like this fragment of a sine wave has an apparent linear secular trend (R² = 0.9945).
The only apparent cyclicity in HadCRUT4 above the 11/22-yr period is at the third harmonic (~54-yr period). I think this corresponds to the ~60-yr period identified in the GISP2. You simply can’t see the millennial cycle in the instrumental data. The Antarctic data are of too short a record length to even see the 50-60-yr cycle.
I know the Holocene climate is cyclical. It sticks out like a sore thumb in the Greenland ice cores and in the non-Hockey Stick reconstructions. But, the instrumental data simply have too short of a record length.
Can I just say that in the context of BBC scandals, the term Mr ‘Fix it’ has very negative associations. I wouldn’t want it next to my name.
kim says:
Look, it’s simple. All they’ve got left is catastrophic sea level rise from the Greenland Ice Cap(which sits in a bowl) sliding into the sea, or the WAIS suddenly falling into the sea.
Whilst a lot of attention is being paid to temperature what appears to be missed is that an ice shelf is going to subject to cyclic mechanical forces due to tides. Is it possible for something akin to “metal fatigue” to occur in ice?
I have seen no mention of the changes in the Earth’s gravitation that, for whatever reason, are taking place all the time. I assume these are taken into account in the models and that in discussing sea level anomalies, gravitational effects are discounted in favour of AGW?
What peer review process and what journalism? The Mayans did get that qualitative ending right.
Resourceguy says:
December 27, 2012 at 2:42 pm
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I agree.
What I find most worrying (and damning) in this whole affair is the quality (or rather lack thereof) of the peer review system. If it lets through papers of this quality, what hope is there for science in this field?
Reblogged this on The GOLDEN RULE and commented:
This article shows how the warmist “science” cons the public.
( Abstract
There is clear evidence that the West Antarctic Ice Sheet is contributing to sea-level rise.)
Is the Ice Sheet a floater, or supported on land?
If it is a floater they have got it wrong from the start.
“David H. Bromwich,1, 5 Julien P. Nicolas,5, 1 Andrew J. Monaghan,2 Matthew A. Lazzara,3 Linda M. Keller,4 George A. Weidner4 & Aaron B. Wilson1”, me and you and a dog named Boo.
Never in the field of science was so little owed by so few to so many (sorry Winston).
“These results argue for a robust long-term meteorological observation network in the region.”
More funding? And more papers? The Beat goes on, and on,……… into retirement…..
Vukcevic , I just scanned for some more info on CPW and found this on french CNRS site, mortality of Emperor Penguins who apparently don’t like not being cold enough!
http://www.cebc.cnrs.fr/ecomm/En_ecomm/WWL_po03.html
Now as soon as I saw that I see two waves not one. If you note the small peaks in ’73 and 82 you will realise it’s two cycles of about 5.5y and 6.25 ? years (not the 4 or 5y claimed by the penguin pokers). Now I don’t know if penguins make good thermometers but those numbers rang a bell.
I recently looked at Pacific and Atlantic autocorrelation:
http://i45.tinypic.com/23lgrix.png
The most obvious short cycle in N.P. is 22y / 4 =5.5 y ; there also seems to be an obvious beating of two close cycles, estimating the null to be about 39y at 6.5 cycles, that makes 39/6.5=6.0y
So 5.5 and 6.0y in N.P.
Flip up to the Arctic and look at rate of change sea ice coverage:
http://i49.tinypic.com/xudsy.png
and there’s a cycle of 5.4 y. That is by far the most sensitive and hence accurate measurement of the bunch, I would say that is correct to better than 0.1y in the period.
I would guess that the N.P. and penguin frequencies could easily be that value too.
P. Solar says:
December 27, 2012 at 7:50 am
Re:: – Circumpolar current
………..
Something fairly regular seems to happen at the other end as well. Though seems a bit longer. http://i49.tinypic.com/xudsy.png
…………..
Here
http://www.vukcevic.talktalk.net/EMFspectrum.htm
spectral analysis shows those links with the common frequencies, but by far strongest component is of the same period as in the solar magnetic field (Hale cycle).
@ur momisugly Vukcevic,
The Hale cycle correlates fairly well with the peak at the 8th harmonic (~20.4 years) in the HadCRUT4 power spectrum.
BBC replied to my complaint – Mr McGrath himself.
The reply to the complaint is worse than the article.
Apart from thanking me for getting in touch, the reply comprises 2 sentences that say 1) the same report appeared in the NYT, Daily Mail, Reuters and others and a reading of those would lead to the same view as the BBC’s about the paper’s contents and conclusions. And 2) that he suggests that if I have any other questions about thepaper I should contact the journal that published it.
“Unless there is some reason to assume that a logarithmic, exponential or other type of function would better capture the trend, linear regressions are generally the best choice.”
The problem is that people can’t resist extrapolating their linear trend. It’s understandable when someone with little mathematical education discovers Excel’s Add Trendline and figures that Apple stock will be $1,000,000 per share in a year. But even folks with lots-o-math in their backgrounds, like Foster (F&R 2011), can’t resist extrapolating a straight line into the future.
This isn’t as much of a problem with non-time-series, since we intuitively know that saying a 1-ton human should be 60 feet tall is unrealistic extrapolation. But, as F&R 2011 shows, it’s easy take a couple of decades worth of data, do a linear regression, and extrapolate it decades into the future.
Henry@Wayne2
I determined that all of warming can be explained naturally by the 88 year Gleisberg solar cycle
http://blogs.24.com/henryp/2012/10/02/best-sine-wave-fit-for-the-drop-in-global-maximum-temperatures/
.See also my last comment there
…..so there is no man made global warming….
So if you know the underlying natural trend, which happens to follow a sine wave curve,
then, to make things interesting for the popular press,
you can chose the date from whence it starts showing the (predictable) linear downward trend,
for example here from 2002:
http://www.woodfortrees.org/plot/hadcrut4gl/from:2002/to:2013/plot/hadcrut4gl/from:2002/to:2013/trend/plot/hadcrut3vgl/from:2002/to:2013/plot/hadcrut3vgl/from:2002/to:2013/trend/plot/rss/from:2002/to:2013/plot/rss/from:2002/to:2013/trend/plot/gistemp/from:2002/to:2013/plot/gistemp/from:2002/to:2013/trend/plot/hadsst2gl/from:2002/to:2013/plot/hadsst2gl/from:2002/to:2013/trend
they can then start looking at that trend and begin to start worrying….
David Middleton
http://www.woodfortrees.org/graph/hadcrut4gl/detrend:1/window/fourier/magnitude/from:2/to:50
Henry@David
there is no indication of the units of measurement?
Henry@Richard Bingham
I also complained, here in Holland where I am visiting, at the Volkskrant, which ran the same article. We will see if they will print my letter. As I always say: you can bring a horse to the water but you can not make him drink. There are none so blind as those who do not want to see.
I am sure they will find out one day…
1942 +88=2030
http://www.google.co.za/url?sa=t&rct=j&q=winter42.wpl&source=web&cd=1&ved=0CDAQFjAA&url=http%3A%2F%2Fxa.yimg.com%2Fkq%2Fgroups%2F21524100%2F12735163%2Fname%2Fwinter42.wpl&ei=zpnYULnHFoGV0QWiqYDIDg&usg=AFQjCNHrFgVwHqxPBwLeTxbtc-3hGjHq_g&bvm=bv.1355534169,d.d2k
@HenryP,
It’s in the frequency domain. The x-axis represents harmonic cycles and the units would be cycles per ~162 years. The y-axis is magnitude/amplitude. The dominant peaks occur at the third (~54-yr) and eighth (20-yr) harmonics.
Should be: “The y-axis is magnitude (amplitude).”
David Middleton
“The instrumental record (HadCRUT) captures about 160 years’ worth of data, all of which is on the up-slope of the millennial scale cycle. It should appear to have a linear secular trend, just like this fragment of a sine wave has an apparent linear secular trend (R² = 0.9945).”
When I first came across trigonometry at school we we taught a very simple test to help in distinguishing between a staight line and a curve. With 160 years of data it is possible to divide the data into three periods of, say 53 years each and to determine the gradients of each of the three. Are these similar? If they are then there is a good chance that a linear approximation is sufficiently accurate. If not then this is an obvious indication either of the existence of some much shorter cycle (or cycles) overlaying the millenial or that there is no cyclicity at all and chaos prevails.
Perhaps, as climate scientists are fond of 30-year periods, we should repeat the exercise with five consecutive, but independent, periods of 30 years each. But sceptics know that 30-year oeriods are too short to provide any real evidence and anyway this has already been done and the 30-year gradients have been found to differ significantly. As David Middleton says “.. the instrumental data simply have too short of a record length”.
By the way thanks for the enjoyable debunking of Bromwich et al.
the post-1980 series depicts a statistically insignificant (R² = 0.01) trend of 0.3 °C per decade
Henry says
I think that should be (R2=0.10)?
David says: It’s in the frequency domain
http://wattsupwiththat.com/2012/12/27/antarctic-warming-courtesy-of-mr-fix-it/#comment-1184717
Henry says
you cannot have cycles both on the y and x ?
Climate is dominated by the Gleisberg cycle which is 88 years, which, it seems, you did not even plot?
http://blogs.24.com/henryp/2012/10/02/best-sine-wave-fit-for-the-drop-in-global-maximum-temperatures/
David Middleton says:
December 28, 2012 at 6:49 am
@ur momisugly Vukcevic,
The Hale cycle correlates fairly well with the peak at the 8th harmonic (~20.4 years) in the HadCRUT4 power spectrum.
Hi David
I would put it the other way around; here are some of my thoughts on the subject:
– 21.3 Hale cycle years period is the primary component
For the moment I would say that ENSO is 4th harmonic of the primary (harmonics being higher in frequency, i.e. shorter periods).
– 16 years could be the Earth’s core-crust internal resonance (possibly triggered by the Hale cycle) equal to the propagation time in either direction, ref: Hide & Dickey),
16 year period is the strongest component in the Arctic temperature spectrum, while on the opposite side in the Antarctic it’s second harmonic (about 8 years) appear to be the Circumpolar temperature wave’s period.
– All ‘components’ in between are products of cross-modulation.
You and many others may have good reasons to disagree, and that is fine with me.
Re above: Here is the link
http://www.vukcevic.talktalk.net/EMFspectrum.htm
Black Pearl (December 27th; 5.33 a.m.) has it spot on.
Back in September the BBC’s Environment correspondent, David Shuckman, ran a piece (with no opportunity to comment) on both the blog and on tv, about the Arctic ice ‘melting at astonishing speed’.
We all know that this was due to a strong storm breaking the ice up – and then of course not a peep when the ice re-formed ‘with astonishing speed’ in October. Now seems to be right on course for a very normal winter (courtesy of Norsex satellite graphs).
But – hey – no story when its normal, is there..?
This paper by Bromwich et al. is possibly the worst ever to have been discussed here at WUWT. It is so bad its evil. Wishful thinking is raised to the level of
“data”. It represents a decay in scientific thinking and the experimental basis of science that was established at a high personal price by the likes of Regiomontanus, Galileo, Brahe, Copernicus, Vesalius, Hook and Newton. More is at stake (at the stake?) here than merely the climate debate.