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« Weather outlook: poor, expect gales - Josh 170 | Main | Gleick "cleared" »
Thursday
Jun072012

Another Hockey Stick broken

There are some important findings at Climate Audit today. Once again I have tried to set out a layman's version of the discussion there.

One of the perennial problems with temperature reconstructions has been a lack of data covering the southern hemisphere - the Hockey Stick itself was a northern hemisphere reconstruction, although the IPCC billed it as global in extent. However, a recent paper by Gergis et al sought to partially remedy this by presenting an Australasian temperature reconstruction for the last millennium, based on 27 proxy records, primarily from tree rings and corals. The headline was, perhaps not unexpectedly, that late twentieth century warming was unprecedented:

The average reconstructed temperature anomaly in Australasia during A.D. 1238–1267, the warmest 30-year pre-instrumental period, is 0.09°C (±0.19°C) below 1961–1990 levels.

However, when the paper was examined in more detail, alarm bells began to be sounded. Concern centred around the proxy data sets used in the study.

Gergis et al reported that they had used 27 proxy series, but that they had selected these from a larger body of data. This was a critical step in the process and one that could well have led to a bias in the results. Many of the studies in the field of temperature reconstructions rely on "sorting" or filtering the data in some way, either choosing only proxy series that correlate well with their local temperature or alternatively weighting them according to how well they correlate. On the face of it, this is a reasonable approach, as the argument might well be made that if there is no correlation then the series is clearly not a proxy for temperature. However, the problem with this approach is that it amounts to a circular argument; it could be that the correlation between temperature records and proxy data is coincidental. This flaw has been demonstrated by studies in which the proxy series are replaced with dummy data series that wiggle up and down at random. In these studies, it has been shown that most of the time the resultant "reconstruction" is a hockey stick.

However, the good news was that Gergis et al were apparently aware of these issues and they declared that they had found a way around them. According to the paper:

For predictor selection, both proxy climate and instrumental data were linearly detrended over the 1921–1990 period to avoid inflating the correlation coefficient due to the presence of the global warming signal present in the observed temperature record.

In other words, when doing the correlation calculations to determine which proxies they would use, they first removed the twentieth century trend (actually, the 1921-1990 trend) from both the proxies and the temperature records, so that instead of filtering for series with a twentieth century uptick, they were picking records that appeared to match in their year-to-year wiggles.

So far so good, but this would have been a calculation that had to be done with immense care and a replication of it could therefore have been illuminating. However, in order to do this, it would be necessary to obtain all the Gergis data including the series that had been filtered out and not used, and unfortunately Gergis was not playing ball:

The compilation of this database represents years of our research effort based on the development of our professional networks. We risk damaging our work relationships by releasing other people’s records against their wishes. Clearly this is something that we are not prepared to do.

We have, however, provided an extensive contact list of all data contributors in the supplementary section of our recent study ‘Southern Hemisphere high-resolution palaeoclimate records of the last 2000 years’ published in The Holocene (Table S3):

http://hol.sagepub.com/content/early/2011/12/16/0959683611427335

This list allows any researcher who wants to access non publically available records to follow the appropriate protocol of contacting the original authors to obtain the necessary permission to use the record, take the time needed to process the data into a format suitable for data analysis etc, just as we have done. This is commonly referred to as ‘research’.

The refusal to release data was troubling, as it prevented anyone ever being able to replicate Gergis's work. And when Gergis's blog was unearthed and it was revealed that she was a committed environmentalist, the alarm bells became louder still.

Despite the flat refusal to allow replication of the paper, it was still possible to verify certain aspects of the filtering process. In particular, the data for the 27 proxies that had been used was available and so it would be possible at least to replicate the calculation that showed that these had significant correlations to their local temperature once the 1921-1990 trend had been removed. This task was taken up by statistician "Jean Sibelius" but rather remarkably he found himself unequal to the task:

Steve, Roman, or somebody, what am I doing wrong here? I tried to check the screening correlations of Gergis et al, and I’m getting such low values for a few proxies that there is no way that those can pass any test. I understood from the text that they used correlation on period 1921-1990 after detrending (both the instrumental and proxies), and that the instrumental was the actual target series (and not the against individual grid series).

Sibelius's difficulties were confirmed by others, including Steve McIntyre, but perhaps most significantly, by CSIRO's Nick Stokes, who is no sort of a sceptic. Stokes agreed with Sibelius that, when detrended, the correlations for the 27 proxies used in the Gergis reconstruction were insignificant, completely contradicting Gergis's paper. However, extraordinarily, Stokes also ran the calculations without detrending and found correlations that were significant.

I’ve run Steve’s code with and without detrending, and with and without the Quenouille correction. Without detrending (but with zero mean) or AR1 correction all (exc maybe Madang) proxies do seem significant

This seems to suggest that Gergis's declaration that the correlations were based on detrended data was false and that she and her co-authors had indeed fallen foul of the circular argument noted above. The finding of unprecedented warmth reported in the Gergis paper appears as though it is a function of the methodology used rather than of the underlying data.

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References (2)

References allow you to track sources for this article, as well as articles that were written in response to this article.
  • Response
    Never done this before, so it may go pear shaped. But I would really like some ideas on how to cut this down to something that can be sent out to the press.
  • Response
    (I have updated the item with comments below after the Post-Libertarianism blog responded). I suppose it is inevitable that people who are unconvinced by a supposedly strong "consensus" in favour of CAGW are going to be branded as conspiracy theorists, putting them into the same category as 9/11 Truthers, Holocaust revisionists, ...

Reader Comments (121)

@Don Keiller - I am not disagreeing with you. I am just waiting for the time when he claims that he does not, and never has, disagreed with the methods of the paper - even though another method, which he has investigated to some extent, might show better results. You have to keep your eyes on the ball. The fact that Stokes has never actually expressed disagreement means that disagreement should never be implied from any of his other statements.

But we all know what a lickspittle he is.

Jun 7, 2012 at 10:53 PM | Unregistered Commenterdiogenes

There were another two problems with the series, which are more basic.

1. Geography
The study is a

temperature reconstruction for the combined land and oceanic region of Australasia (0°S-50°S, 110°E-180°E)

So why are Palmyra Atoll coral proxy (>2100 km NE), 2 Rarotonga coral proxies (2000km east) or 2 Vostok Ice Station proxies (>3000km S) included?. 5/27 are well outside the area.
http://manicbeancounter.com/2012/06/06/mid-pacific-coral-temperature-proxies-from-gergis-et-al-2012/

2. Proxy Correspondence
Fiji (<150km across) and Rarotonga (<10km across) both have two coral proxies. The temperature proxies, if any good, should give similar results. They are massively different.
http://manicbeancounter.com/2012/06/05/palmyra-atoll-coral-proxy-in-gergis-et-al-2012/

Jun 8, 2012 at 12:37 AM | Unregistered CommenterManicBeancounter

To clarify on my comment at CA. As I said there, I ran McSteve's code. On detrended data, it produced the results he posted. The code looked to me to be doing the right thing, though I didn't check in detail. I have no independent results on detrended. But I adapted it to remove the detrending, while subtracting the mean. Then it gave the results I posted.

I didn't comment further there, but the obvious possibility is that they said they detrended but didn't. Some say you should (including the authors), some say not. You'll find both views at CA.

Jun 8, 2012 at 12:52 AM | Unregistered CommenterNick Stokes

On the June 3rd post at Climate Audit the Gergis paper is merely described as "submitted". Is this now considered sufficient for AR5 inclusion by the IPCC as peer-reviewed literature, even if the "submission" is eventually rejected?

And what is new about the "new" Gergis paleo-records?.....
I would guess that, if pushed, they might say:
"They're the most recent records, so they must be new!".
Or, if that didn't wash, how about:
"They're from the Holocene. Can't get much newer than that!"
:)

Jun 8, 2012 at 1:58 AM | Unregistered Commentermichael hart

"I think that this amounts to academic fraud and should be called as such.
Don Keiller"

You appear to believe, in spite of all the evidence' that 'climate science' is an academic subject; it is just political science under another guise. In the same way people spent decades pointing out the relevance of 'scientific socialism', now the new generation political warriors seek to destroy capilatlism and representative democracy using 'climate science'.

Jun 8, 2012 at 2:38 AM | Unregistered CommenterDocmartyn

Jun 7, 2012 at 10:33 PM | sHx... another zebra down ... just another day on the Serengeti

Skiphil: You took it out of my mouth. ;-)
--------------------------------------------------------

Just another Kangaroo road-kill on the track out of Bourke.

Jun 8, 2012 at 3:02 AM | Unregistered CommenterStreetcred

I'd like to hear from the authors how they actually performed the correlation analysis on the detrended series.

Until we know that and can replicate it, we can't say this is broken, just that it looks broken.
I mean, they may have some schmick new method of testing correlation.
Climate science seems to throw up quite a few novel satistical methods...

Jun 8, 2012 at 3:02 AM | Unregistered CommenterGeoff Cruickshank

Firstly, a tree responds to an absolute average of temperature it is subject to, and not particularly their differences year-to-year.

A tree therefore *cannot* respond to interannual differences alone, without being influenced by the longer-term underlying trend. As far the sensing mechanism (i.e., tree) is concerned, these two are inseperable from each other.

More importantly, the whole premise of the dendrochronologic exercise is an implicit acceptance that tree ring series capture multicentennial variability. We are trying to recover multicentennial variability, primarily, on a data series that is resolved at the interannual scale.

Fishing for correlations against 'detrended' temperature series is therefore a meaningless exercise. Not only that, it is an invalid exercise, under the stated assumptions to begin with.

I would say, the only valid method would be to correlate with local instrumental temperatures and then build a tree ring series drawing from an unselected set of trees of the same biological growth properties. Anything else is circularity.

Jun 8, 2012 at 3:14 AM | Unregistered Commentershub

Following on from the discussion the other day, this is an example where the release of data and code with the paper would allow the exact methodology to be quickly determined. If past history of the team is any guide it could be years until it is revealed.

Jun 8, 2012 at 3:28 AM | Unregistered Commenterredc

I think the problem is McIntyre et al are not replicating what Gergis did. Gergis is using spearman rank correlation instead of pearson, which can be more robust if you have a nonlinear but monotonic relationship between two variables. They also Loess filter to remove low-pass noise.

Nick points both of these issues out on Steve's blog here.

I add some comments related to the above here.

Jun 8, 2012 at 6:27 AM | Unregistered CommenterCarrick

Sorry, my comment is here.

Jun 8, 2012 at 6:29 AM | Unregistered CommenterCarrick

Nick Stokes - instead of everyone fiddling about writing scripts to try and reproduce their results, wouldn't it have been better if they had supplied their code in the first place.

Perhaps someone should put in an FOI request for it. The research was funded by the Australian taxpayer after all, which presumably includes both of us.

Jun 8, 2012 at 6:40 AM | Unregistered CommenterGrantB

Carrick I thought Steve posted those on the other thread?

Jun 8, 2012 at 6:43 AM | Unregistered Commenterredc

Re: carrick

> I think the problem is McIntyre et al are not replicating what Gergis did.

I think the problem is that Gergis et al did not say what they did in enough detail for it to be independently replicated.

Jun 8, 2012 at 7:35 AM | Unregistered CommenterTerryS

Geoff, I think even David Copperfield can not trick those correlations to be significant.

Carrick, Pearson vs. Spearman does not make any difference here, I actually tried those (and also Kendall's tau) immeditely after I observed the low correlations. They used Spearman in Neukom & Gergis (2011), but there is no mentioning of it in Gergis et al. (2012) nor they mention filtering in the context of screening. Why don't you try to do the analysis yourself instead of throwing around useless accusations of "problems" that do not exist?

I'm in complete agreement with Nick Stokes that they likely simply used undetrended unadjusted numbers. A plausible explanation (without need to assume malicious motives) is that they did screening a way ahead of the rest of the analysis, and simply forgot that the particular proxy selection was based on simple correlations.

An interesting question here is how they are going to "fix" this. Knowing the Team practices, I'm confident that this "does not matter". If they accept that the screening is done with the detrended correlations, they need to redo the whole paper. On the other hand, even if they simply say that they used simple correlations for screening, they likely need to redo at least the whole verification part (and be prepared for defending themselves against the "screening fallacy"). I'm sure all the best "statistical" forces (Mann, Schmidt etc.) are now busy trying to come up with a creative "solution". I hardly can wait to see what that is. :)

Are there any news about this from the "Down Under front"? It seems to me that this is not picking up any coverage there although the actual study seems to have been rather prominently displayed all over the news media.

Jun 8, 2012 at 8:05 AM | Unregistered CommenterJean S

"From my reading that means the same tree species correlated in opposing fashion at different locations. For example, at one location a wide tree ring is interpreted as warming, but at another location where the same species is examined a wide tree ring interprets as cooling."

Exactly. Kauri Pines in different parts of the North Island of New Zealand are supposed to have opposite reactions to climate change. Not impossible, but some kind of justification certainly seems called for.

Jun 8, 2012 at 8:13 AM | Unregistered Commentertty

Are there any news about this from the "Down Under front"?

Nope. Zilch. Nada.

Like the rest the of the world, Australia too has been mesmerised by the lying cheating whispers of climate scientists, I'm afraid.

Who knows maybe in six months we'll read on ABC's The Drum an exclusive report on how Gergis made an honest error and that it was fellow climate scientists that spotted the error, blah, blah, blah, eco-psychologist Stephen Lewandowsky or the state-appointed doomsayer, Tim Flannery.

BTW, is there a particular reason why the focus is on Gergis other than the fact that she was the lead author of the paper under scrutiny? Should not 'et al' also be under criticism? Gergis may be excused for being young and foolish. How about senior scientist Karoly sharing some of the blame?

Assuming of course all this is a real zebra hunt and not a wild goose chase.

Jun 8, 2012 at 9:00 AM | Unregistered CommentersHx

I have not read the Gergis paper but I would be surprised that something as simple as correlation based screening cannot be replicated. I am sure that somehow Gergis and Macintyre are not using the same method and I am sure the differences will be rectified.

Be careful w.r.t. positive and negative correlations. The Oxygen isotope data in corals for example will be inversely correlated with local SSTs, while the tree-ring data from Tasmania (for example) will be positively correlated with local land temperatures.

Proxy screening, if done at all, should only be done at the local scale – i.e. does a proxy record provide a valid estimate of local scale temperature variability. Screening against a large scale instrumental target “can” lead to an overfitting situation.

Jun 8, 2012 at 9:15 AM | Unregistered CommenterRob Wilson

Rob

Obviously it's possible, but unless Gergis releases her code, we are all flying blind.

Jun 8, 2012 at 9:25 AM | Registered CommenterBishop Hill

Jean S. asked:

Are there any news about this from the "Down Under front"? It seems to me that this is not picking up any coverage there although the actual study seems to have been rather prominently displayed all over the news media.
-----------------------------------------------------------
After the initial blaze of publicity, all has gone quiet. This is at least partly due to dominant coverage of the Government's catastrophic opinion polls (currently about 30%) and daily news of price rises due to the hated carbon dioxide tax. Today, for example, people in my jurisdiction were advised that our electricity bills will rise around $450 next year, mostly due to the tax. We also learned that the Government's solar energy for schools program is costing about $284 per tonne of CO2 abatement, compared to a world price of about $10 per tonne. Taxpayers are less than thrilled by this kind of news.

In this context, Gergis et al's work is not getting much traction in the MSM, and they are mostly too lazy to do the work required to cover anything happening outside their playpen (such as reading blogs like CA) even if they were inclined to do so. There are a few notable exceptions like Andrew Bolt and some writers on The Australian, but they need a smoking gun to report, and so far the deconstruction of the paper is a bit arcane and technical for them and their readers.

Since working through all the issues will take more time and effort, I can only repeat my thanks to those who are doing it. Hopefully we will reach a point where a headline and plain language article that encapsulates the issues can be written for wider consumption.

Jun 8, 2012 at 9:27 AM | Unregistered Commenterjohanna

Thank you Jean, I defer to your expertise.

Rob, in the comments at Climate Audit it is said that one tree ring series from NZ is negatively correlated and two others not far from it are correlated positively. Similar altitude. The coral negative corr. is recognised there.

Not a whisper of this in Oz that I can find, nor likely to be. Here we release results and move on. These things cannot be re-visited after all, they're peer reviewed.

Jun 8, 2012 at 9:46 AM | Unregistered CommenterGeoff Cruickshank

sHx, at least from my perspective prof. Karoly is excused as he gave me the laugh of the month :)

Karoly says that nothing is certain in science, but the results draw from a range of sites and using state-of-the-art statistical methods can be accepted with high confidence

Rob, sure, any guess what in the heck the method may then be? It is described in the paper as

For predictor selection, both proxy climate and instrumental data were linearly detrended over the 1921–1990 period to avoid inflating the correlation coefficient due to the presence of the global warming signal present in the observed temperature record. Only records that were significantly (p<0.05) correlated with the detrended instrumental target over the 1921–1990 period were selected for analysis. This process identified 27 temperature-sensitive predictors for the SONDJF warm season (Figure 1 and Table 1) henceforth referred to as R27.

Data (27 "identified" proxies + instrumental target) is found here.

Btw, does any one has an idea what happened to this web site:
http://climatehistory.com.au/2012/05/24/1000-years-of-climate-data-confirms-australasias-warming/

Jun 8, 2012 at 9:48 AM | Unregistered CommenterJean S

Jean S.
Personally, I would correlate using both unfiltered records and 1st differenced transforms as linear detrending can be messy if you have odd extreme years at the end of the series (or at the ends of the 1921–1990 period). Ultimately, the empirical screening exercise must agree with the original climatic interpretation of the data. If for example, a negative correlation of a tree-ring record to temperature is biologically meaningful, then that is fine. But I would be rather sceptical of such a relationship.

I suppose those who are trying to replicate Gergis probably need to try both Pearsons and Spearmans as well as compare against both the local relevant temperature data-set and the large-scale instrumental record used for the final reconstruction.

Learning from the past 10 years, Gergis could easily address this by writing a blog post to clarify the situation – either at RealClimate or ClimateAudit. Any criticism could then be quickly diffused. If her record is to be referenced in AR5, then any ambiguities need to be nipped in the bud now.

Jun 8, 2012 at 10:13 AM | Unregistered CommenterRob Wilson

Like the disappearance of the blog, the page on the website was removed but it's still in Google's cache. As far as I can tell the website is related to the researchers.

Jun 8, 2012 at 10:38 AM | Unregistered Commenterredc

Jean S,

"Btw, does any one has an idea what happened to this web site:
http://climatehistory.com.au/2012/05/24/1000-years-of-climate-data-confirms-australasias-warming/"

Indeed. It's gone. It is less than 24 hours since the existence of that website was reported in this thread. And I am positive the missing page contained links to the media organisations that reported Gergis et al's super science. Now it's all wind and tumbleweed.

Edit: I see redc has already dug it out. I believe more pages are missing from that site.

Jun 8, 2012 at 10:42 AM | Registered CommentersHx

Eventually found my post ... not at the bottom with the comments as I expected, but at the top.

But the request for help remains! I've got three letters to write to the BBC today, plus we could do with help writing some articles. So, if anyone has spare time and wishes to help the cause please do get in contact at SCEF.

Jun 8, 2012 at 10:47 AM | Registered CommenterMikeHaseler

Rob Wilson
"Proxy screening, if done at all, should only be done at the local scale – i.e. does a proxy record provide a valid estimate of local scale temperature variability. Screening against a large scale instrumental target “can” lead to an overfitting situation."

Indeed, and Gergis et al did calculate local grid temperatures as shown in their Fig S1. But Steve M used the aggregate temperature that they designated as their "target" for the reconstruction.

It's not clear in the paper or the earlier paper of Neukom and Gergis what temperature measure they did calibrate with. And they should have, although it may be one of those things that people in the field take for granted. But until this is established the SteveM/JeanS analyses should be regarded sceptically. It's no use using what could be quite the wrong temperature.

Jun 8, 2012 at 10:51 AM | Unregistered CommenterNick Stokes

"Only records that were significantly (p<0.05) correlated with the detrended instrumental target over the 1921–1990 period were selected for analysis."

Nick: Are you suggesting they used 27 different local detrended instrumental targets?
Then why call them "the detrended instrumental target"?

Jun 8, 2012 at 10:59 AM | Unregistered CommenterGeoff Cruickshank

Nick: it's made quite clear in the paper that the instrumental target is the spatial mean of Hadcrut over Australasia.
Rob: Jean and Steve have tried various things. It's clear there is a serious error (not an 'ambiguity') in the paper.

"Learning from the past 10 years,"
This erroneous paper is a splendid example of the failure of climate scientists to learn anything from their previous mistakes.

Jun 8, 2012 at 11:08 AM | Registered CommenterPaul Matthews

Nick Stokes
"But until this is established the SteveM/JeanS analyses should be regarded sceptically."

I am no scientist so I steer clear of all technical discussions. I try to read them so far as I can understand.

As a layman, I see on one side a bunch of climate scientists hiding and ignoring the requests for data and code again!. Two weeks ago they were the toast of the town. Now they've gone into hiding, taking their once beloved websites with them.

On the other side I see a small group of amateur enthusiasts with a proven track record for openly nailing down dodgy science. Perhaps they are mistaken in this instance but I believe Steve Mc's blog posts usually faces greater scrutiny than papers in peer-reviewed literature.

All in all I know who to be skeptical of. Unless and until Gergis et al explain to us why Steve Mc and others are wrong, Gergis et al ought not be trusted as honest or reliable scientists.

I am glad to see Rob Wilson and Nick Stokes are involved at this early stage. They can witness for themselves how this saga evolves in real time.

Meanwhile, search parties have been sent out to locate Myles Allen and Richard Betts.

Jun 8, 2012 at 11:16 AM | Registered CommentersHx

Thought:

If the 27 proxies used are not correlated with the spatial mean target series then there is no circular reasoning involved is there?

The paper is then flawed because the description of method is wrong, but the final result is a PCP analysis of 27 proxies which are definitely not cherrypicked. (by that method anyway).

Jun 8, 2012 at 12:12 PM | Unregistered CommenterGeoff Cruickshank

No, that was a stupid thought. I see Nick has pointed out that the series are actually correlated if you don't detrend them.

Jun 8, 2012 at 12:18 PM | Unregistered CommenterGeoff Cruickshank

Geoff, no, the proxies ARE correlated with the spatial mean target in its raw form (so circular reasoning applies).
They are NOT correlated with the de-trended target, as claimed in the paper.
That's the interpretation of the numbers posted at CA by Jean and Nick.

[sorry - I see you get that now]

Jun 8, 2012 at 12:18 PM | Registered CommenterPaul Matthews

sHx, it seems like the third author of the paper is also busy editing his web site.

Jun 8, 2012 at 12:33 PM | Unregistered CommenterJean S

It's not the whole website that's gone missing (so far as I can see), it's that specific page on this Gergis et al (2012) paper. This might suggest there is some scrambling going on behind the scenes to start figuring out a response to all this?? although 'disappearing' a web page is never a good start from the standpoint of honesty and transparency.

[From the home page of that website as I'm viewing it right now]:

Unearthing Australia’s climate history

This landmark project, spanning the sciences and the humanities, draws together a team of leading climate scientists, water managers and historians to better understand south-eastern Australian climate history over the past 200–500 years. It is the first study of its kind in Australia.
About the project

The project is led by researchers from the University of Melbourne’s School of Earth Sciences. The aim is to investigate south-eastern Australia’s climate history using the following sources:

Palaeoclimate records: tree rings, coral, ice cores and cave deposits

Documentary records: newspaper articles, governors’ records and early settler accounts

Early weather data: weather journals, government gazettes and pre-Federation observatories

These records will allow us reconstruct past climate conditions (rainfall, temperature and atmospheric pressure) and see how climate variability has influenced Australian society over time.


btw, for our statistical lions, there may be some useful info about their stats here:


Neukom and Georgis (2011) Southern Hemisphere high-resolution palaeoclimate records of the last 2000 years

Jun 8, 2012 at 12:34 PM | Registered CommenterSkiphil

Rob Wilson-
It would seem, both from the words in the paper and from the fact that only the regional instrumental temperature record appears in the data archive for Gergis 2012, that they did not use local temperature records in the selection process. In fact, looking at their figure S1, the local temperature history does not correlate well with the regional average, at the locations of some of the proxies, e.g. Bali, Bunaken, Maiana.
.
And the Urewara proxy shows a significant negative correlation with [regional] temperature. If there were a biological reason for accepting this as a proxy (rather than using it in an inverted manner), oughtn't it to have been mentioned in the paper?
.
I think your suggestion of a post on methods by Gergis (or one of her co-authors) is excellent. Or releasing the code (which is a point I made elsewhere). Either way allows the resolution of methodology issues. [I suspect other ones, such as the overall reliability of the conclusions of the method, will remain contentious.]

Jun 8, 2012 at 12:42 PM | Registered CommenterHaroldW

A bit of a tangent from technical discussion of the paper, but Dr. Gergis does not seem to harbor any doubts that studies of past "natural variability" will surely support the C-AGW agenda (the cart before the horse and all that??):


"In 2011 volunteers from the OzDocs project discovered devastating locust plagues, sweeping floods, burning heat waves and snow falling in Sydney during colonial times. The launch of the new website in 2012 will accommodate a far greater number of volunteers who will continue to recover Australia’s climate history at an unprecedented rate."


I find it interesting that Dr. Gergis seems so certain that she already knows the 'answer' to the question of whether past climate variability is exceeded by present to future climate change driven (ostensibly) by human actions (passage is hyper-linked):

"The OzDocs project was primarily founded to help bridge the gap between climate scientists and members of the wider community.

“An important part of this project is to help the community understand the difference between natural climate variability and how industrially-driven climate change since the 1950s is amplifying our already extreme climate in ways not experienced in the past,” said project leader Dr Joelle Gergis."


So this otherwise valuable "citizens" project in climate history seems to have a settled agenda to promote C-AGWarmism. I'm all for improving our historical climate knowledge in a genuine scientific spirit, but Gergis seems awfully certain that any info about past climate extremes can be put into her narrative about future catastrophe. Interesting.....

Jun 8, 2012 at 12:56 PM | Registered CommenterSkiphil

Could someone tell me why Gergis et al would use Spearman's rank correlation? The distribution of anomalies is normal and not skewed, after all? Is that the line of reasoning?

Jun 8, 2012 at 1:02 PM | Unregistered CommenterShub

Geoff,
"Nick: Are you suggesting they used 27 different local detrended instrumental targets?"

Yes. Although I take the point that this does not fit with the language. So I don't know.

It's just that they could have done that, they had and plotted the necessary data, and it seems like the right thing to do. So yes, something's wrong.

Jun 8, 2012 at 1:08 PM | Unregistered CommenterNick Stokes

Also, while one must exercise caution in parsing remarks from different contexts, it is difficult to reconcile the utter certainty Gergis displays in what the OzDocs project will prove to citizens about C-AGW with this candid (2011) acknowledgement that the scientific study of SH climate is in its "infancy":

"....although large-scale climate reconstructions
for the SH are in their infancy...." Neukom and Gergis (2011)

Jun 8, 2012 at 1:15 PM | Registered CommenterSkiphil

In the paper they say:

Our instrumental target was calculated as the
September–February (SONDJF) spatial mean of the HadCRUT3v 5o x 5o 180 monthly combined land
181 and ocean temperature grid (Brohan et al., 2006; Rayner et al., 2006) for the Australasian domain
182 over the 1900–2009 period. The SONDJF seasonal window correlates highly with the MAMJJA
183 season (r=0.87) and the annual mean (r=0.93) on inter-annual timescales over the 1900–2010
184 period. Since the HadCRUT3v grid contains significant amounts of missing data in the pre-1900
185 period across the region, the 1850–1899 section was excluded from our analysis (Jones et al., 1999;
186 Brohan et al., 2006).
187 To assess the large-scale coherence of land and ocean temperatures over the broad Australasian
188 region, we performed a correlation analysis to identify all HadCRUT3v grid cells displaying a
Page 8 of 53
significant positive correlation with the predictand 189 over the 1900–1990 period (Figure S1). This
190 analysis revealed a high degree of spatial coherence of warm season temperatures over the
191 Australasian region with the exception of areas in Western Australia containing missing values,
192 parts of south east Asia influenced by local monsoon variability, the data sparse region of the
193 Southern Ocean, and the mountainous area of eastern Australia. Overall, 73% of grid cells (100 out
194 of 137) were significantly positively correlated (p<0.05) with the Australasian spatial mean (Figure
195 S1). This result is not surprising as the flat, arid continent of Australia and its surrounding ocean
196 dominates the majority of Australasian, confirming that reconstructing a spatial mean of coherent
197 temperature over the region is an acceptable approach for the region.
198 2.2.


I think it's clear from this what their " instrumental target" is.

Possibly another lot of correlations that need checking though.

Jun 8, 2012 at 1:38 PM | Unregistered CommenterGeoff Cruickshank

Gergis seems to know already how the "natural variability" narrative should go, even though both the historical period of the past 2 centuries and the paleo reconstruction period of 1 to 2 millenia have hardly begun to be studied. I am having trouble understanding this as a "scientific" outlook:

Briefing sheet on another project for which Dr. Gergis is Lead Researcher, a project in reviewing documentary history of the past 2+ centuries for climate data

[this is quotation from the 'briefing' sheet not necessarily a direct quote from Dr. Gergis]:

"Climate models predict [emphasis added] that Australia’s densely populated southeast will become warmer and drier under climate change. But in order to establish how the current changes can be viewed in a context of long-­‐term natural variability, these reconstructions of past climate are crucial."


btw, there's that word "PREDICT"...... so are the models predicting the future or not?

Jun 8, 2012 at 1:44 PM | Registered CommenterSkiphil

JeanS, redc, skiphil, indeed, the climatehistory.com.au site that hosted the disappeared blog post was set up by, guess who, Joelle Gergis. See the last entries at her blog

http://web.archive.org/web/20100401101127/http://joellegergis.com/

- which she also recently deleted!

Jun 8, 2012 at 2:09 PM | Registered CommenterPaul Matthews

a couple of excerpts (below) from the "disappeared" website page, which appears to be more of a press release than any independent article..... this SEARCH website is evidently the project website for Gergis who got the $950K grant referenced by sHx earlier on this thread.

h/t to redc for linking the Google cache link above to retrieve the "disappeared" content (I am guessing the reason it could be disappeared so fast is that Dr. Gergis is in control of this website, it will be interesting to confirm whether or not this is the case)..... Like most netizens I disdain "disappeared" content that has been published..... if you want to make changes or corrections make them openly, with transparency.

We are continually told that all these climate issues are of immense, world historic importance ("for our grandchildren").... so when will scientists begin to insist that everyone in their field(s) be held to high professional standards? This web page has evidently been sent down an Orwellian memory hole, except that Google cache saved it for us:


1000 years of climate data confirms Australasia’s warming

"The last 60 years have been the hottest in Australasia for a millennium and cannot be explained by natural causes according to a study recently published in the Journal of Climate by SEARCH project scientists...."

....

"“Our study revealed that recent warming in a 1000 year context is highly unusual and cannot be explained by natural factors alone, suggesting a strong influence of human-caused climate change in the Australasian region,” said Dr Joelle Gergis, lead author of the paper."

[edit: cross-posted with Paul Matthews 2:09, thanks Paul!!]

Jun 8, 2012 at 2:15 PM | Registered CommenterSkiphil

Ohhh there is so much "interesting" info on and about that SEARCH website for SH climate history. It does indeed appear to be the personal (collaborative) project for which Dr. Gergis won that grant. The last "WhoIs" registry under the name of Josh Cockfield at the University of Melbourne is also interesting, since he is the only named author on a variety of "News" items on that website. Thus it's highly likely that he is the project mgr. or comm. mgr. for the Gergis project:

Whois response for climatehistory.com.au:
Domain Name climatehistory.com.au
Last Modified 14-Dec-2011 00:08:21 UTC
Registrar ID Enetica
Registrar Name Enetica
Status ok
Registrant UNIVERSITY OF MELBOURNE
Registrant ID ABN 84002705224
Eligibility Type Registered Business
Registrant Contact ID JC2260702
Registrant Contact Name Josh Cockfield
Registrant Contact Email info@climatehistory.com.au
Tech Contact ID JB1092280
Tech Contact Name Josh Bassett
Tech Contact Email josh.bassett@gmail.com
Name Server dns.site5.com
Name Server dns2.site5.com

Jun 8, 2012 at 2:38 PM | Registered CommenterSkiphil

Jean S 12.33, interesting.
Here's another article about Gergis et al that has mysteriously disappeared.

Any chance the paper itself might disappear?

Wow - it has disappeared. No longer at the AMS website
http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-11-00649.1

Jun 8, 2012 at 2:59 PM | Registered CommenterPaul Matthews

Skiphill,

Although Joelle Gergis blog has completely disappeared (except for webcite and google cache, of course), only a few pages are missing from climatehistory.com.au web page.

The curious thing is that all those pages did not go missing at the same time. Joelle Gergis blog went missing some two or three days ago. The climatehistory.com.au began losing pages only in the last 24 hours.

I believe the principals involved in the Gergis paper are following this and Steve Mc's blog in real time, and yet they refuse to respond. They just go on quietly deleting all evidence of a great discovery by the Gergis team.

Now, this is pure speculation, but the fact that the Gergis team has not responded so far and the fact that they are erasing some (not all) of their tracks on the web as they're identified suggest that there isn't a single mind trying to control the fallout.

I believe there is a discord within the team that authored the Gergis et al paper on how to respond to Steve Mc's challenge.

This is pure speculation but we shall see.

Edit: Yes, Paul Matthews, that pages on the UNSW web has also been made to disappear is a pretty significant and robust stuff.

Jun 8, 2012 at 3:10 PM | Registered CommentersHx

sorry, my last for a good long while I hope! This item below must be shared.... it is (unintentionally) quite funny! Gergis writes in March 2010 for a university audience about the "guerilla war" over climate policy (embracing Chris Mooney's account). She provides with obvious approval what seems to be her paraphrase of remarks by Mooney: "Most people know how easy it is to click the ‘publish’ button on a blog, but in reality, very few know the rigours of publishing evidence-based science in the peer-reviewed literature."

==============================================================

Winning the guerrilla war on climate change at Science meets Parliament 2010


Winning the guerrilla war on climate change at Science meets Parliament 2010

By Joelle Gergis, School of Earth Sciences

.....

"....American science writer Chris Mooney outlined the ‘guerrilla war’ on climate science in the untamed jungles of the online world. He said it was naïve for scientists to feel that the ‘truth will prevail’ as the mountain of peer-reviewed evidence grows. He suggests that as a community we must equip ourselves with the professional communication skills to combat the targeted tactics of our opponents. Most people know how easy it is to click the ‘publish’ button on a blog, but in reality, very few know the rigours of publishing evidence-based science in the peer-reviewed literature...."

....

"...At the end of our time in Canberra, we left with the clear message that scientists are welcome in the political process, but we must equip ourselves with effective communication tools so the essence of our knowledge is heard. We need to be prepared to defend our science in the face of intense public scrutiny, concisely, with conviction and in plain English. Once we restore community confidence in climate science, one conversation at a time, our politicians will have no choice but to follow...."[emphasis added]

====================================================================

Well Dr. Gergis, "intense public scrutiny" is here, it's your time in the sun. Let's see you defend, modify, or retract your work as appropriate. That "community confidence in climate science" is at stake, as you well know.

Jun 8, 2012 at 3:12 PM | Registered CommenterSkiphil

"Climate models predict [emphasis added] that Australia’s densely populated southeast will become warmer and drier under climate change. But in order to establish how the current changes can be viewed in a context of long-­‐term natural variability, these reconstructions of past climate are crucial."
----------------------------------------------------------
Densely populated? You could fit 3 mainland Britains in it with room around the sides, and the current population is about 10 million. And, guess what? This part of Australia is not the sandy desert part, it is one of the the reasonably well-watered parts, which is why people live there. There are other well watered parts, some the size of several European countries, which are also growing.

They must think that we are idiots.

Jun 8, 2012 at 3:20 PM | Unregistered Commenterjohanna

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