UPDATED: See below for Stephen McIntyre’s response, with details of emails showing that Joelle Gergis did not independently discover the problem but learnt of it from Climate Audit.
The Gergis hockeystick was heralded in the media for a week in 2012 before it was cut apart online and months later, quietly withdrawn. Headlines raved that Australia was having the “hottest years in the millennium”. As I said at the time, it was all silly beyond belief — the whole study relied on two bunches of trees in Tasmania and New Zealand to tell us that the greater continental area was 0.09°C warmer now than it was in 1000AD. If trees in yonder Tassie can tell the whole continental temperature to a tenth of a degree, who needs thermometers (especially the kind which need 2 degree corrections)? Why does the BOM bother today?
Part II of this sorry paper has arrived under this auspicious headline at The Conversation:
Still hurts eh?
Look out. The Scientific Saints have arrived!
According to Joelle Gergis, skeptics found just “one typo”, and in Gergis’ own words “Instead of taking the easy way out and just correcting the single word in the page proof, we”...“set about rigorously checking and rechecking every step of our study.”
As you would right? The typo was so trivial Team-Gergis went on to take four more years to do “…three extra rounds of peer-review” with “four new peer-reviewers”, not to mention “countless rounds of internal revisions made by our research team and data contributors.”
I bet Gergis wishes she had got that word right in the first place.
All up, the paper went through “nine rounds of revisions, and was assessed a total of 21 times.” Gergis proudly says: “One reviewer even commented that we had done “a commendable, perhaps bordering on an insane, amount of work”.
Insane is the word. This is setting a new bar in scientific hair shirts. You would almost think Joelle Gergis felt guilty for something?
Welcome to a university-world dilemma: should I correct one word or do four years hard labour?
Then again, perhaps The Typo did matter?
UPDATE: It’s not a “typo”, it’s a “bug”. As Dean from Ohio adds: “A typo is in text, where it can usually be detected and autocorrected, as it were, by the reader. A mistake in software (computer code) is called a bug, not a typo, and can hardly ever be detected and corrected mentally because the information space of all possible program outputs is so vast. “
Gergis writes about the skeptics who found the typo/bug:
Enter the bloggers
It turned out that someone else had spotted the typo too. Two days after we identified the issue, a commenter on the Climate Audit blog also pointed it out.
The website’s author, Stephen McIntyre, proceeded to claim (incorrectly) that there were “fundamental issues” with the study. It was the start of a concerted smear campaign aimed at discrediting our science.
McIntyre’s helpful corrections (thanks to Nick Stokes and Jean S.) are associated with “a smear campaign”. In the same vein, an unkind soul might reply that the bloggers were only correcting what was a shameless self-serving media push to get alarmist headlines.
Note that McIntyre is described as a “website author”, just a blogger. They could have described him as a published scientific author with a track record of finding holes in these kinds of papers. (Are the editors at The Conversation feeling threatened by independent, unfunded citizen scientists?)
What bad luck for Gergis that she discovered the mistakes two days before McIntyre and co, but didn’t think to email the hockeystick expert himself, so he could help spread the word and correct the misinformation going out over the media. I’m sure McIntyre would have been interested, and happy to pass on her correction. (See his reply below, her claims are a “fantasy”).
The new graph of the last thousand years in Australia
Four years work, and one word typo corrected, this below is the new graph. Notice how modern times are as hot as 1300AD but only when instrumental records (the orange line) are compared to tree rings. One day, when Tasmania gets trees again, we will be able to compare tree rings to tree rings.
There may (hopefully) be other historic proxies involved this time, but a proxy is a proxy. If it works in 1300AD, why doesn’t it work in 2000AD?
If we just look at the black PCR construction it would appear that all the extra CO2 didn’t make much difference. The proxy record has shown more variability, and similar temperatures when CO2 levels were supposedly perfect.
How do we know that last bump after 1950 is supernatural? Here’s the press release.
Climate scientists used natural climate indicators, such as tree rings, corals and cave records, in conjunction with climate modeling to delve a thousand years back into the region’s temperature history. — Phys Org
“Analysis of climate model simulations shows that the warming experienced since 1950 cannot be explained by natural factors alone, highlighting the role of human caused greenhouse gases in the recent warming of the region.”
So there you have it. Models that don’t work in this millennia, and don’t explain the bumps of the past millennia, also cannot explain the current bump. That’s modern science: you get 95% certainty and argument from ignorance in the same sentence.
Tell us how good peer review is again
Gergis was not happy that her paper was used to show how flawed peer review was:
Former geologist and prominent climate change sceptic Bob Carter published an opinion piece in The Australian claiming that the peer-review process is faulty and climate science cannot be trusted.
Then again, Bob had a point. Gergis used 300,000 dollars and took three years to produce a flawed paper. Bloggers corrected Gergis’ mistake for free in three weeks. Peer review had missed it completely in the first place, then took four years to get it right.
What about those error margins
As Mike E then pointed out in comments, the error margin in 2012 was larger than the result:
“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.”
Still hopefully, they fixed “one typo” and the uncertainty estimates. Looks like the hottest 30 year period back then, and reported to hundredths of a degree, may not have turned out to be the hottest thirty year period of that era in the new study.
Not so unprecedented
The new press release even admits things have been just as warm in Australia all those years ago:
“Analysis based on the smallest subset of the palaeoclimate data network suggests that single 30-year and 10-year periods of comparable temperatures to late 20th century levels may have occurred during the first half of the millennium.
That’s a fundamentally different announcement to the headlines the paper scored in 2012:
The Guardian: “Australasia has hottest 60 years in a millennium, scientists find”;
Where is the honesty in the Gergis essay that the conclusions of the new version are quite different and the past headlines were wrong?
UPDATE: From Stephen McIntyre
Gergis’ account of events is a fantasy. Among other things, her claim to have discovered the error two days prior to Climate Audit is a fabrication. The issue of ex post screening was raised at Climate Audit on May 31, with particular concern over spurious regression between trends. Gergis et al was defended by a couple of commenters who pointed out that Gergis’ correlations were (supposedly) done using de-trended series. Jean S then checked this claim, pointing out that their correlations failed with detrended data, from which we concluded that they had not done their calculation the way that they claimed. Jean S comment was posted on June 5 16:42 blog time (-5). This was 23:42 Swiss time (+2) and 7:42 am June 6 AET (+10).
Neukom sent Gergis an email notifying her of the problem at June 6 9:46 am AET (+10), June 6 1:46 am Switzerland (+2). Neukom, Gergis and Karoly then discussed the bad news.
Both at the time and in her recent article, Gergis claimed that they had discovered the problem “independently” of Climate Audit, but this is contradicted by emails showing that they had been reading Climate Audit and by the above timeline.
There are of course many other untruths in her article.
From data that’s mangled and squeezed,
One tenth degree warming is teased,
As a trend to be claimed,
And on mankind is blamed,
To keep global warmists appeased.
Joëlle Gergis et al. (2016) Australasian Temperature Reconstructions Spanning the Last Millennium. Journal of Climate . DOI: 10.1175/JCLI-D-13-00781.1