Crowdsourcing the WUWT Paleoclimate Reference Page – Disputed Graphs – Alley (2000)

Photobucket.com – Click the pic to view at source

Image Credit: Photobucket.com – GISP2 – Alley, 2000

By WUWT regular “Just The Facts”

In building WUWT Paleoclimate Reference Page during these crowdsourcing threads (1, 2) there have been a number disputes raised about various graphs. During this thread I am hoping that we can determine logical classifications for graphs based upon Alley, 2000. In future crowdsourcing threads we will have to address an array of other disputed reconstructions including Briffa et al., 1998, Jones et al., 1998, Mann et al., 1998, Pollack et al., 1998, Jones et al., 1998, Mann et al., 1999, Mann et al., 2000, Briffa et al., 2001, Esper et al., 2002 and Jones and Mann 2004, AR4 section 6.6.1.1 2007 and Marcott et al. 2013.

Thus far three methods have been used for classifying disputed graphs on the WUWT Paleoclimate Reference Page. The first is to add a “Graph Background” link to offer additional pertinent details. The second is to add a Disputed Graph label to the graph, along with a brief description of the nature of the dispute. The third is to place the graph in the section at the bottom of the Paleoclimate page titled Incorrect/Falsified Graphs along with a longer description of the reason the graph is incorrect or has been falsified. Your suggested improvements to our graph classification methodology are most welcome.

I this thread I’d like to solidify the classifications for the graphs based upon Alley, 2000. The dispute around Alley, 2000 has focused on the axis labels, as WUWT commenter Phil states here

Any graph that claims to use Alley’s GISP2 data must either finish at 95 years Before Present (BP=1950) or AD1855 because that is the final date in his database which is on-line and freely available to us all. Lappi’s graph mistakes Present for 2000 as does Easterbrook, they should have a note added pointing out their error or be excluded.

Based on Alley’s own Figure 1 from his 2000 paper;

Photobucket.com – Click the pic to view at source

the x axis label is Age (thousand years before 1950) or Years Before Present (1950AD) and the Alley, 2000 data clearly ends 0.0951409 thousand years Before Present. Taking that into account, the following are the graphs from the WUWT Paleoclimate Reference Page know to be based upon Alley, 2000 and their proposed Classifications:

2,500 Years – GISP2 – Alley, 2000    Classification: Correct – No Change

Photobucket.com – Click the pic to view at source

10,000 Years – GISP2 – Alley, 2000    Classification: Correct – No Change

Photobucket.com – Click the pic to view at source

10,000 Years – GISP2 – Alley, 2000     Classification: Correct – No Change

Tinypic.com – Click the pic to view at source

10,000 Years – GISP2 – Alley, 2000, Ljungqvist et al and HadCRUT3     Classification: Correct – No Change

Photobucket.com – Click the pic to view at source

10,000 Years – GISP2 – Alley, 2000          Classification: Confusing – Add Label: Disputed Graph – The x axis label should read Years Before Present (1950 AD)

BP.Blogspot.com – Click the pic to view at source

10,000 Years – GISP – Alley, 2000 – Vostok – Petit et al. 1999 – Click for Animation –      Classification: Confusing – Add Label:  Disputed Graph – The x axis labels should read Years Before Present (1950 AD)

WUWT – GISP – Hadley – Click the pic to view at source

10,000 Years – GISP2 – Alley, 2000     Classification: Incorrect – Move to Incorrect/Falsified Graphs section – Label Incorrect Graph – The x axis label, “Years Before Present (2000 AD)”, should read Years Before Present (1950 AD)

Lappi – JoNova.com – Click the pic to view at source

10,000 Years – GISP2 – Alley, 2000       Classification: Incorrect – Move to Incorrect/Falsified Graphs section – Label Incorrect Graph – The x axis label, “Years Before Present (2000 AD)”, should read Years Before Present (1950 AD)

Easterbrook – Figure 5 – Click the pic to view at source

Please provide your thoughts and recommendations on these proposed graph classifications and labels for the Alley graphs, as well as any other improvements, corrections or other additions to the WUWT Paleoclimate Reference Page in comments below.

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The problem I have is using Greenland cores or Greenland temperature as a representation of global climate. Greenland is subject to extremely local weather events, some of which can be persistent on a decadal scale. Changes in persistent pressure areas and jet stream flows can cause significant local changes in Greenland temperatures. In fact, I saw a paper recently that compared O18 in Swiss speliothems with Greenland ice cores. While there were some correlations there were also some cold periods in Greenland that didn’t show up in Switzerland and even when they did show up together there was a considerable lag of time between them.
I’m just skeptical of using Greenland ice cores because there is no way to sort out local changes from global changes.

Gerg Goodman

The idea of vetting and classifying seems to be good one. However, assimilating a graph covering 10k years with a careless error of 50 years “before present” issues with something that is falsified seems unreasonable and improper.
The axis labelling issue is worth flagging but this does not fall into the same category as falsification.
Things like Jones and Mann cropping , padding , grafting etc is clearly falsification.
It would be to dilute their sins to confound that will a rather insignificant technical error of not correctly noting what “before present” is defined as.

Laurie Bowen

Yep, I like the Years Before Present (xxxx AD) much clearer for these kinds of graphs.
I have always been interested in all the creative ways scientists have gone about trying to infer the temperatures of the past, whether “relatively” recent or ancient. And given that; I would hope any would understand why such minor variations (above) are simply a “noise factor”, given; the flucuations over the “four” seasons for a particular longitude, latitude and altitude.
When I was young, a change in climate simply meant that the seasons were changing from spring to summer or from fall to winter, and for some of us that was “dramatic” enough.

Steve Keohane

How about changing the the x-axis labels to be correct.

Reblogged this on This Got My Attention and commented:
Disputes among “climate scientists”?

Gerg Goodman

NOAA graph should be labelled as misleading for plotting temperature record along side and as continuation of GISP2.
The two datasets are incompatible and cannot be compared like that. The time resolution of the sampling interval is not the same and there is a physical averaging process on a decadal scale in ice/firn closure.
Plotting the two on the same graph clearly is intended to make that comparison and is thus misleading and not scientifically valid.
The only one that may pass the test is the second one showing 2500 y GISP2. But …

Gerg Goodman

2500 y GISP2 , best of the bunch but though the 10 year running mean looks to have similar variance to the GISP data this is presumably more by luck than judgement and it still has unsmoothed data which is not compatible.
Also running mean appears to run up to the end of the data which means it’s been padded with something. Likely by duplicating last value. This will bias strongly towards one final value this is not representative of the data and also not compatible for reasons in previous post.
So why all these graphs?
The only thing I can see as being legit is a straight plot of Alley’s data.
If someone has studies the physical time constant of the damping effect of closure time and done an equivalent processing on temp record, that may be legit. I don’t see that being done anywhere here .

richard telford

Splicing the Northern Hemisphere HadCRUT3 record onto the GISP2 reconstructions is awkward. If there is any Arctic amplification, one might expect temperature change in Greenland to be greater than the hemispheric mean.
And what is the reference for your identification of Bond peaks and troughs. They don’t exactly match the cycles Bond identified.

Greenland instrumental record is almost equal to the whole Arctic, that is very similar to CET and CEt is almost identical to NH. Today Greenland temperature is similar to 1930-40s.

Gerg Goodman

One thing that seems a serious omission on the paleo page is the origin of all these plots. Many have a link to Alley’s paper but that is not the origin of the graph.
Anything provided on that page should have a clear and prominent link to the source of the graph.

Alley 2000 is flawed because the isotope paleothermometer is flawed. Every meteoroligst, knows that the most important factor that determines the “cloud temperature” is dew point. But it’s the cloud temperature and rayleigh rain out effect that is ultimately determines the isotope ratios on the ice cores. Hence we’re essentially looking at dewpoints, not at temperatures.
If you compare the i snow accumulation at the ice cores and the isotopes, it’s a near perfect match r2 96% that is simply because both are proxy of the same, wet or dry climate.
More here:
https://dl.dropbox.com/u/ 22026080/non-calor-sed-umor. pdf.

Gary Pearse

crosspatch says:
April 13, 2013 at 12:22 pm
“The problem I have is using Greenland cores or Greenland temperature as a representation of global climate. Greenland is subject to extremely local weather events, some of which can be persistent on a decadal scale.”
Isn’t the warming of a warm period exaggerated in Arctic-subarctic latitudes?

Rob Dawg

If I may be so bold. Every data set needs to be °K with the following parameters:
Resolution: Years for which individual measurements span. Is Marcott 300 years? ±150 years or what?
Graph span: A graph that starts 11k BPE and draws trend lines might need to discard several hundred years at both ends for the purpose of trend graphing.
Reference temperature: The temperature against which differences are measured. This makes for several important tests. One, if the reference temp can be verified by other methods. Second if better amplification factors can be deduced. Rather than just tossing out a dataset it can perhaps be rescued.
Resolution, span, reference point.

justthefactswuwt says:
April 13, 2013 at 2:14 pm
I didn’t identify anything, these are all 3rd party graphs. The goal here is to determine if the graphs are accurate or not. As such, please present evidence and links to support your assertion that the Bond Cycle Peaks and Troughs labeled on this graph;
—————-
Without referencing the source of all of the information, the graph are almost useless. The best place to find the timing of Bond cycles is presumably Bond et al. (1997). The last two cold events listed are at 1.4 and 2.8 kyr BP (no little Ice Age, because of missing core tops).
http://rivernet.ncsu.edu/courselocker/PaleoClimate/Bond%20et%20al.,%201997%20Millenial%20Scale%20Holocene%20Change.pdf

Neville.

Interesting to read that Briffa, Jones, Vinther et al paper again and look at their table 1.
If we look at the annual temp for Greenland in the decade 1851-60 we have a temp of minus -2.1c. ( annual)
Then if we look at the decade 1981-90 we have an annual temp of minus-2.5c
Then if we look at the decade 1991-2000 we have an annual temp of minus -2.1c.
Alley’s graph ended in 1855 and we can now show above that the period from 1980 to 2000 was 0.3 C colder than the decade 1851-60. That’s a period of twenty years.
Here is that study. http://www.cru.uea.ac.uk/cru/data/greenland/vintheretal2006.pdf The Table 1 is on page 11.
Interesting how the recent winters and springs ( 1980 – 2000 ) were colder than the 1851- 60 period as well.
PLEASE NOTE. This is a post from another blog I wrote about a couple of weeks ago..

David McKeever

How about making more categories, such as ‘Lie’;, ‘Misleading’, ‘Mistaken’ ? I would put the chart with the wrong BP date as ‘Mistaken’.

R. Craigen

Seems to me that the graph as a faithful representation of the data is more critical than the correct labelling of its axes. The former determines whether or not the graph is “correct”; the latter is a hygene issue that can be amended.
I do think you have the right categories, only how to partition the graphs into these categories may take a bit of tweaking.
Personally, whether it is labelled so or not, the use of the word “Present” to denote the date 1950 is confusing. Further, other graphs use 2000 etc for “present”. Any permanent repository of graphs ought to have a more absolute standard of labelling. Somehow my eye missed the parenthetic base date in the titles and it took me a while to get oriented to reading them before trying to assimilate the graphic.
This is a lot of work — I’m very glad to see someone putting in the time to straighten it out. Thanks.

lurker passing through, laughing

Let’s crowd source CG3.

Purely as an aside – “Years Before Present” is surely one of the stupidest modern inventions, because “present” is not a constant and it runs backwards. As a committed atheist, I see no problem whatsoever with simply using the date used by all of the connected world, regardless of its origin. However, if something else has to be used, and if “years before present” doesn’t mean years before present but means “years before 1950″ then call it YABY (Years After Base Year”, where Base Year is whatever anyone wants to call it that makes it equal to what most people call “1950”.

GregK

Haven’t seen much reference to Senna and others 2009.
http://www.clim-past.net/5/523/2009/
Their conclusions are not dissimilar to Marcott’s [that’s Marcott’s thesis not Marcott et al, “Science”]

Bill Illis

The polar amplification factor in Alley 2000 versus Global temperatures (and all the borehole calibrated Greenland ice cores) is 5 to 1
So the temps in Alley 2000 change by 5 times as much as the global temperature.
A very similar ice core (NGRIP) versus a global temperature estimate over the last ice age.
http://s18.postimg.org/6rih4vhrd/Greenland_vs_Global_Temperatures_135_Kya.png

On Bond ‘cycles’: http://www.leif.org/EOS/Obrochta2012.pdf
“Our new results suggest that the “1500-year cycle” may be a transient phenomenon whose origin could be due, for example, to ice sheet boundary conditions for the interval in which it is observed. We therefore question whether it is necessary to invoke such exotic explanations as heterodyne frequencies or combination tones to explain a phenomenon of such fleeting occurrence that is potentially an artifact of arithmetic averaging”

Ian W

justthefactswuwt says:
April 13, 2013 at 1:24 pm
Gerg Goodman says: April 13, 2013 at 12:25 pm
The idea of vetting and classifying seems to be good one. However, assimilating a graph covering 10k years with a careless error of 50 years “before present” issues with something that is falsified seems unreasonable and improper.
The axis labelling issue is worth flagging but this does not fall into the same category as falsification.
Things like Jones and Mann cropping , padding , grafting etc is clearly falsification.
It would be to dilute their sins to confound that will a rather insignificant technical error of not correctly noting what “before present” is defined as.
———————————–
But the graphs are incorrect, regardless of the the method and motivations. And 50 years is quite important when the warming of the second half of the 20th century forms the entire basis of the Catastrophic Anthropogenic Global Warming narrative.
Once we start to deal with Jones, Mann, Marcott, etc. we can consider whether it makes sense to break out the Incorrect/Falsified Graphs section into multiple sections, but for now I am inclined to leave it as is. What does everyone else think?

I think that you could be falling into the ‘Marcott’ trap. 50 years is totally unimportant in a 10,000 year plot and most of the proxies in that 10,000 years are unable to discriminate a 50 year value. As long as the proxies are reliably shown in the graph it would be better just to truncate the time axis. We are dealing with climate not weather so 50 years is unimportant.

This again? GISP2 is an O16/O18 proxy ratio measurement..it is NOT a measurement of local Greenland climate..it is a better proxy for Hadley Cell strength and tropical/subtropical SSTs.

William Astley

In reply to
crosspatch says:
April 13, 2013 at 12:22 pm
The problem I have is using Greenland cores or Greenland temperature as a representation of global climate. Greenland is subject to extremely local weather events, some of which can be persistent on a decadal scale.
philr1992 says:
April 13, 2013 at 6:24 pm
This again? GISP2 is an O16/O18 proxy ratio measurement..it is NOT a measurement of local Greenland climate..it is a better proxy for Hadley Cell strength and tropical/subtropical SSTs.
William,
Crosspatch statement is not correct, regions of the planet do not warm or cool for hundreds of years do to local weather conditions. Philr1992 you are using terms in a sentence with the hope that they will support your position which it appears is that the Greenland Ice Sheet temperature data should be suppressed.
The Greenland Ice sheet is representative of the temperature in the Northern Hemisphere, with some qualifications. The Dansgaard-Oeschger (D-O) cycles, the obvious dominate warming and cooling cycle, periodicity 1450 years plus or minus 500 years, in the GISP2 Greenland Ice core analysis is also observed in ocean sediment analysis. The D-O cycles and the glacial/interglacial cycles is relevant to the climate change discussion.
The problem is not the data, but the fact that data does not support the ‘message’. A component of the ‘message’ is that the 20th century temperature rise is unprecedented which it is not.
http://www.climate4you.com/images/GISP2%20TemperatureSince10700%20BP%20with%20CO2%20from%20EPICA%20DomeC.gif
http://www.climate4you.com/
P.S. Thank-you every one that is bringing the paleo data to Watts up. The attempts to make the D-O cycle go away as it off ‘message’ are ridiculous, pathetic, and sad.
The people how are pushing the ‘message’ have attempted to suppress the paleo climate data, as it does not support their ‘message’. A very small percentage of the general population are aware of the D-O cycles. A very small percentage of the population are aware that interglacial periods are short, roughly 12,000 years, that we are at the end of this interglacial period and that the past interglacial periods ended abruptly.
https://ams.confex.com/ams/pdfpapers/74103.pdf
The Sun-Climate Connection by John A. Eddy, National Solar Observatory
Solar Influence on North Atlantic Climate during the Holocene
A more recent oceanographic study, based on reconstructions of the North Atlantic climate during the Holocene epoch, has found what may be the most compelling link between climate and the changing Sun: in this case an apparent regional climatic response to a series of prolonged episodes of suppressed solar activity, like the Maunder Minimum, each lasting from 50 to 150 years8.
The paleoclimatic data, covering the full span of the present interglacial epoch, are a record of the concentration of identifiable mineral tracers in layered sediments on the sea floor of the northern North Atlantic Ocean. The tracers originate on the land and are carried out to sea in drift ice. Their presence in seafloor samples at different locations in the surrounding ocean reflects the southward expansion of cooler, ice-bearing water: thus serving as indicators of changing climatic conditions at high Northern latitudes. The study demonstrates that the sub-polar North Atlantic Ocean has experienced nine distinctive expansions of cooler water (William: And nine expansions of warmer water which unfortunately is politically incorrect to acknowledge) in the past 11,000 years, occurring roughly every 1000 to 2000 years, with a mean spacing of about 1350 years.
Each of these cooling events coincides in time with strong, distinctive minima in solar activity, based on contemporaneous records of the production of 14C from tree-ring records and 10Be from deep-sea cores. For reasons cited above, these features, found in both 14C and 10Be records, are of likely solar origin, since the two records are subject to quite different non-solar internal sources of variability. The North Atlantic finding suggests that solar variability exerts a strong effect on climate on centennial to millennial time scales, perhaps through changes in ocean thermohaline circulation that in turn amplify the direct effects of smaller variations in solar irradiance.

Just the Facts:
This may be picky; but the graphs have titles! Use them when referencing!
e.g. Some graphs (most if not all) have a lead in description “10,000 Years – GISP2 – Alley, 2000 Classification: Correct – No Change”
Whereas the graph states (if I have the right graph); “Holocene Epoch with HADCRUT3”
I agree with some of the other commenters; “Years before present” is a useless boat anchor identifier. Yeah the graph is third party; so add a note stating clearly when the present time is assumed to be.
I second the notion that all spliced charts should be identified! If possible add smaller graphs depicting the splices.
Love the animated graph; it’s a little fuzzy though. Would it be possible t make it stop action till clicked?
Definitively identify any graph that is ‘soiled, contested, disputed, in question, not replicated or replicable, data/code is lost or worse, refused
To fail to identify graphs that fail honest science questions will open WUWT to being cited as a proponent of the graphs by their inclusion (as research cites).
And; thank you for doing this JTF!!

Ian H

If the graph simply needs a change of labelling or description then calling it “falsified” seems much too strong. Even calling it “disputed” seems an overreaction to this type of error. I would prefer a label along the lines of “acceptable with correction or clarification”.

Mike McMillan

If we’re relabelling the x-axes, the AD comes before the year.

Sorry, I still like this graph from GISS data:
http://suyts.files.wordpress.com/2013/02/image_thumb265.png?w=636&h=294
I think it tells the whole story.
By using a normal Y-axis, it is clear that global warming has stalled…
Anyone want to dispute this graphic???

Gerg Goodman

JTF “Every graph is linked, just click on the pic and it will take you to where it was found/hosted.”
Yes , I did realise that and was surprised that I just got some ‘pastbin/dropbucket’ not the true origin. I did not realise that a lot of these graphs are of unknown origin.
Another label “origin unknown” would seem to be in order where that is the case.

Gerg Goodman

“If we’re relabelling the x-axes, the AD comes before the year.”
I don’t think anything should be changed on any graph. Otherwise you go and get the data and plot the graph yourself in the way you think it should be done.
Notes should be used to explain any issues with dates.
If the labelling issues have a significant impact on how the graph is read, label it as misleading/falsified , whatever, or just don’t use it all.
Is there a need to deal with every anonymous unattributable graph in a pastebin on the internet?

Gerg Goodman

JoNova/Lappi and WUWT/Easterbrook graphs :
Both these graphs have insufficient labelling of content to stand alone. They need a link to the article which presumably explains more. (Lappi green line is what? Why is it valid? Valid what?)

William Astley says:
April 13, 2013 at 7:24 pm
The Sun-Climate Connection by John A. Eddy
Eddy said: “Based on the assumption of an increase in the amplitude of irradiance variations that accompany slower changes in solar activity, about half of the documented rise in global surface temperature in the period from about 1900 to 1940 can be ascribed to solar changes. In the remaining years of the century the fraction falls to about one fourth of the total rise in temperature, with the remainder attributed to ever increasing greenhouse warming. But it must be emphasized, once again, that the larger-amplitude, slower changes in solar irradiance on which these deductions are founded have yet to be observed.”
And that is precisely the point. In the ten years since Eddy’s paper, the assumption has crumpled and there is no good evidence of these longer periods in TSI. There are even some hints of TSI being higher during grand minima [since there are no dark spots to decrease TSI].
On Bond ‘cycles’: http://www.leif.org/EOS/Obrochta2012.pdf
“Our new results suggest that the “1500-year cycle” may be a transient phenomenon whose origin could be due, for example, to ice sheet boundary conditions for the interval in which it is observed. We therefore question whether it is necessary to invoke such exotic explanations as heterodyne frequencies or combination tones to explain a phenomenon of such fleeting occurrence that is potentially an artifact of arithmetic averaging

JTF – I’ve researched this pretty deeply, as its been an ongoing question. There is more to it than simply stating 1950 = “present” is correct. First there must be definitive proof what the correct date for “present” really is for Alley 2000. There is circumstantial proof, and even pretty good anecdotal evidence, that 1950 is correct, but as you note it is very important to know with certainty what the actual date is.
Don Easterbrook claims present = 2000, and there are a number of versions of the Alley 2000 graphs that say that. I believed, from my original review, that 1950 was correct. But based on the lack of Alley being able to offer any definitive answer I dug in to it again. I still believe it may have been the intent and/or belief that 1950 was correct, but as I work my way back upstream from Alley I no longer believe that is a definitive answer.
I have reached out to Don, to try to get to the bottom of it, and hopefully will get a reply soon.

Gerg Goodman

OK , some digging. The 10k Alley graph seems to be _derived_ from the one produced in SS.org rebuttal of the Easterbrook graph. Easterbrook clearly did not understand what he was doing with the dates and did not bother researching even when questioned. Their arguments against his graph seem sound. “Invalid” seems correct label.
However, the Alley 10k graph has been crudely modifies by someone. I could not understand the blue “GISP dite temps” label stuck up in the air. The reason is because they’ve moved the data !!
So “falsified” would be best there.
The following would seem to the original, with the article to explain it’s derivation:
http://hot-topic.co.nz/wp-content/uploads/2011/01/GISP210klarge.png
The 1.4 deg C shift is derived from the previous graph showing “reconstructed Greenland temperatures for the period 1840-2007 ”
http://hot-topic.co.nz/wp-content/uploads/2011/01/GRIPtempBox480.png
There is a link to the paper and it turns out that it’s a mix of recent weather station data and _climate model_ reconstructions.
http://journals.ametsoc.org/doi/abs/10.1175/2009JCLI2816.1
The text comments: ” It’s clear there is a calibration issue between the long term proxy (based on ∂18O measurement) and recent direct measurement of temperatures on the Greenland ice sheet. How that might be resolved is an interesting question”
So we move from _climate model_ reconstructions to “recent direct measurement” . The noted calibration issue is not resolved but the 1.4 deg C rise in the MODEL reconstruction is used anyway.
So I would suggest moving the current Alley 10k graph to “falsified” (which I would still like to see separate from simple errors of labelling) and replacing with SkS and a link to the originating article.
The graph also gets “disputed/misleading” for mixing incompatible data. “Assuming” GISP and GRIP sites vary by 0.9 deg C , shifting the 1.4 rise from an air temp climate model on to GISP2 data is simply unjustified. Especially when the text notes an unresolved calibration problem that it does not even attempt to resolve. What they are effectively doing is “resolving” it by assuming there is a fixed difference between the two stations and that there is NO calibration or compatibility issues between the modelled air temp and GISP2 core “temps”.
Totally unfounded.
The GISP2 + 1.4 deg C line is clearly labelled so I’d say this is misleading rather than falsification. However, presenting model output as “GISP site temp” and referring to “recent direct measurement” is borderline falsification.

Gerg Goodman

“I agree that falsified is strong for some”
Indeed but not unjustified in some cases. For example Mann’s padding the filter window with later instrumental temps when actual data were available from Briffa for those years. This “trick” was to ensure that the smoothed line totally masked the graphing of instrumental data on to the cropped off Briffa proxy data.
That was artful and deliberate falsification.
Whoever, took what was labelled as GRIP site temp and shifted it down 0.9 deg C leaving the label also falsified the graph.
I think it should be used sparingly since it implies intent. There are cases however, where that is justified.
I think it is important to separate that sort of thing from Easterbrook’s apparent bodge due to not understanding the subject.

Gerg Goodman

graphing of instrumental data on to the cropped off Briffa
oops, I meant _grafting_ . The result of the contamination is bend up the end of cropped Briffa data, that is still coloured as Briffa line. It was a fraud.

Gerg Goodman

http://joannenova.com.au/2010/02/the-big-picture-65-million-years-of-temperature-swings/
Found source of Lappi graph. No explanation of his quadratic (?) fitted model , what it means or why it’s there or how we might interpret it. Nada.
It does not add anything to the std Vostok record other than this unexplained line.
I’d like suggest labelling it “disputed” but since he does not say what he’s done it’s hard to dispute. That essentially makes it invalid/irrelevant.