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Posts Tagged McLean

Saturday snark: a textbook for Vincent Gareth Renowden Feb 01

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As Stoat points out, the IPCC has released the reviewers comments on the Working Group One second order draft report. And as you might expect, the IPCC’s favourite inexpert commenter, the New Zealand Climate “Science” Coalition’s very own Vincent Gray was busy reviewing their work. Here’s comment 1-549 from Chapter One (pdf) by Gray:

The records shown are not “observations” and they are not “temperatures”. They are also not “globally averaged. They are a set of multiple averages, subtracted from an overall average, compiled from a vaying non-standardised set of maximum an minimum temperature measurements at varying weather sations and ship measurements. They were previously treated as “Mean Global Temperature anomaly” The uncertainties attached to each figure are very great, individual temperature measurements are rarely accurate to better than one degree, so a claimed “trend” over 100 years of less than one degree has a very low level of statistical significance. [Vincent Gray, New Zealand] (all spelling from IPCC doc)

The response from the editors is a minor classic of its kind:

Rejected – The comment does not reflect the scientific understanding. The errors in individual observations are not additive; we are also doing relative analysis that eliminates many of the concerns about individual errors. The reviewer obviously has a limited understanding of the associated error evaluation for analysis of large datasets. See Chapter 2 for more on the evaluation of these datasets. Or maybe even read a basic textbook. (my emphasis)

For more on accuracy versus precision, and the statistical power of large numbers, this classic post by Tamino is well worth a read.

There are other minor gems to be found as the reviewers deal with Monckton (in the “general” section) and John McLean (seemingly everywhere). In fact McLean’s ubiquity suggests that he may have acceded to Gray’s throne as the man with most comments on a single IPCC report. But don’t expect me to add them all up, I do have a life…

NZ Herald’s turn to offer propaganda as opinion – De Freitas’ links to cranks hidden from readers Gareth Renowden Sep 12

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The new “compactNZ Herald has taken a downmarket tabloid approach to informing its readers by running an opinion piece about the recent courtroom defeat for NZ’s climate cranks by prominent climate sceptic and Auckland University geographer Chris de Freitas, without explaining de Freitas’ long history of association with the cranks he’s defending. In the article, de Freitas overstates the uncertainties associated with temperature records, even going so far as to imply that the warming trend over the last hundred years might be “indistinguishable from zero”1. He also overplays the importance of temperature series to policy-makers — a line straight out of crank litigant Barry Brill’s playbook, and self-evident nonsense.

Despite this transparent partiality, the opinion editors at the Herald credit him like this:

Chris de Freitas is an associate professor in the School of Environment at the University of Auckland.

But, as the Herald opinion team well know, de Freitas is much, much more than a mere associate professor in the School of Environment. He has a track record of activism against action on climate change that stretches back two decades. Here, for the poor misled readers of the new Herald‘s opinion pages is a handy, cut-out-and-keep guide to de Freitas’ long history of climate denial activism.

This long list is far from complete — not least because it doesn’t include all the sceptic nonsense he’s presented as opinion at the NZ Herald and National Business Review over the years3, but it should serve to give a flavour of the man that Herald readers might think was a humble and respectable geographer at the University of Auckland.

The Herald has no excuse for failing to explain de Freitas’ interests in this issue, and should print a clarification as soon as possible. Carrying a good piece by Brian Rudman may “balance” CdF’s effort in some eyes, but the paper really needs to do better. What next? An opinion piece criticising the Labour party by prime minister John Key, where he is described as “a retired banker”?

[Updated 13/9 to add CEI link, and CdF's publication record.]

  1. “Temperature trends detected are small, usually just a few tenths of one degree Celsius over 100 years, a rate that is exceeded by the data’s standard error. Statistically this means the trend is indistinguishable from zero.”
  2. It didn’t.
  3. A rough count suggests that since 1990 he has published around 77 opinion
    pieces about climate change – with 32 in NBR and 27 in the Herald – partial publication record here.

McLean’s folly 2: the reckoning Gareth Renowden Jan 12

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Ten months ago, Aussie “sceptic” John McLean predicted that 2011 would be “the coolest year since 1956″. I pointed out at the time that this was nonsense, and so it has proven to be. I’ve taken the GISS global temperature figure for Jan – Nov 2011 (+0.51ºC compared to the 1951-80 average) and added it to the graph I created to illustrate the full extent of McLean’s folly:

Maclean1956outcome

Last year was warmer than 1956 by a whopping 0.68ºC — about three standard deviations, in statistical terms — making McLean’s forecast an abysmal failure. Yes, 2011 was cooler than 2010 or 2009, but still one of the top ten warm years.

ENSO does have an effect on global temperature — that’s been understood since the 1970s, if not earlier. La Niña years tend to be cooler than the years around them, as this WMO graph illustrates.

2011LaNina

It’s clear that even cool La Niña years have been warming, with 2011 being the warmest such year in the instrumental record.

The reason McLean’s forecast failed is quite simple. He failed to take into account the warming trend that’s incredibly obvious when you look at the GISS and WMO data. Why would he do that? Well, he was lead author on a paper that “established” a link between ENSO and global temperature, but did that by filtering the global mean temp to remove any long term trend and to emphasise the ENSO time scale. Voila! The Southern Oscillation Index (SOI) suddenly accounted for most of the variability in the (filtered and detrended) global mean temperature. As pointed out in the rebuttal to McLean et al, just about any time series would be “explained” by the SOI after passing through their filter.

In order to make his unphysical forecast, McLean must have forgotten what he had done in the paper he was so keen to promote. I could perhaps be forgiven for suspecting that he didn’t know what he was doing in the first place — but then that just makes his co-authors, Chris de Freitas and Bob Carter look equally daft. They certainly didn’t rush to correct McLean’s folly. As ever, in the land of the Climate Cluelessâ„¢, anything goes.

See also: McLean, de Freitas and Carter win the Friends of Gin and Tonic’s inaugural Climate Idiots of the Year award. Richly deserved.

[A glimpse of stocking.]

Predicting the bleeding obvious (and getting it wrong) Gareth Renowden May 31

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A couple of days ago one of the leading figures in the New Zealand climate crank pantheon, the Climate “Science” Coalition’s very own Bryan Leyland, popped in to Hot Topic and left a comment drawing attention to his new favourite game — “predicting” global temperatures by projecting the southern oscillation index forward seven months. He bases this on the “work” of John McLean, last mentioned here a couple of months ago when I looked at his prediction (happily promoted by the NZ C”S”C) that 2011 will be the ’coolest year globally since 1956 or even earlier’. Suffice to say, it won’t be.

Leyland first notes the infamous McLean, De Freitas and Carter paper of 2009, then his own “prediction” that this year’s La Niña would bring a cooling in global temperatures, and then says:

What is remarkable about this is that a retired engineer with access to the Internet has been able to make accurate predictions of future climate. Yet, to my knowledge, no computer-based climate model nor any mainstream ’climate scientist’ predicted this cooling. To me, this is truly remarkable.

What’s really remarkable is that Leyland is actually only showing his ignorance of some pretty basic climate relationships.

As I commented when McLean et al was published (back in 2009), we’ve understood that the state of the El Niño Southern Oscillation (ENSO) has an impact on global temperatures for a very long time indeed. The Climatic Research Unit’s Phil Jones showed this in a paper in 19891, and the Swedish meteorologist Hildebrandsson may have written about the idea in the 1890s2. Even more obvious perhaps, for a retired engineer with an internet connection, you can trawl back through the Goddard Institute for Space Studies GISTEMP web site, and find comments about ENSO’s effect on global temperatures. This is what they said a decade ago:

The global warmth in 2001 is particularly meaningful, because it occurs at a phase of the Southern Oscillation in which the tropical Pacific Ocean is cool. The record warmth of 1998, in contrast, was bolstered by a strong El Niño that raised global temperature 0.2°C above the trend line.

Not only that, but GISS has been producing and updating this figure (source) since it was first published in 1999:

GISTEMPFig E201104

The influence of ENSO on global temperatures amounts to common knowledge amongst those who study climate. When a La Niña follows an El Niño, you get a cooling. That’s not news. And when the current La Niña ends 3 temperatures will pick up again, and we’ll be heading back into record territory. That’s because the underlying planetary energy imbalance isn’t going away, and the main driver of that imbalance — the amount of CO2 in the atmosphere — is increasing every year. Take a look at another GISTEMP graph (source):

DTs 60+132mons201104

This shows the global average temperature smoothed over 60 months (to minimise ENSO impact) and over 132 months (to reduce the effect of the 11 year solar cycle). There’s only one way that line is heading (barring a volcano or two) and that’s up.

Leyland finishes his soothsaying with a chilling warning:

Records from all over the world show that a long sunspot cycle is followed by cooling in the next cycle and a short sunspot cycle indicates warming. The last sunspot cycle was 12.5 years and the previous one was 9.5 years. The evidence tells us that a 3 year increase in cycle length will result in cooling of at least 1°C. As the total amount of warming that has occurred since the early 1900s is 0.7°C, this is potentially very serious. We could be returning to the conditions in the little ice age.

The only reference Leyland gave me for this assertion was a pdf of one his talks, which contains a few unreferenced slides (it’s turtles all the way down). However, the solar cycle length effect is one of the oldest and most effectively debunked theories offered by sceptics, as this page at Skeptical Science points out. On that flimsy basis, Leyland goes one better than his pal McLean, who you will recall predicted that this year could be as cool as 1956 (not looking good, that one) and warns that over the next decade we might see a return to global temperatures last seen a century ago4. Let’s see what that might look like:

Leylandprediction

McLean’s 1956 prediction was stupidly implausible. Leyland at least ensures that his year to year fall (at about -0.1ºC per year) is within the range of physical possibility, but requires every year for a decade to be cooler than the last if he’s to reach his goal — wiping out 150 years of global warming. Unfortunately, that’s just as implausible because it completely ignores the growing energy imbalance I noted above. That’s not going to change any time soon.

So, in the real world, where might temperatures be heading? Arthur Smith at Not Spaghetti took a look at this a couple of months ago, using statistical models (based on a post by tamino at Open Mind) that account for all the major climate drivers. His “model 1″, with ENSO set to neutral, is plotted in red above. As you can see, after a pause this year caused by the current La Niña, we get back into record territory in 2012. With the current solar cycle ramping up (which increases the amount of energy reaching the earth from the sun), and La Niña ending, temperatures move on up. Barring volcanoes, this where I expect global temperatures to go in the near term.

The lesson here is pretty simple. Leyland is pleased to trumpet his ability to make a trivial prediction because he appears to lack the sort of straightforward understanding of the climate system that would be available to anyone willing to read an introductory textbook. That lack of understanding leaves him prey to any old tosh — which is abundantly available around the crank web. When you rely on the Climate Cluelessâ„¢ for your science education, you end up looking foolish.

PS: Leyland also reminded me that I had offered to bet against his proposition that world would soon enter a cooling phase. If Leyland is willing to stick with his prediction as graphed above, then I will happily bet $1,000 that the world will not cool by 1ºC over the next 10 years. We might also be able to frame a shorter term bet. Over to you, Bryan.

  1. Jones, P.D. (1989). The influence of ENSO on global temperatures. Climate Monitor 17: 80-89
  2. Salinger, J. pers comm
  3. This year or next, take your pick — Klaus Wolter (MEI) gives a 50% chance of the current event extending into 2012.
  4. I assume that’s what he means — one degC cooling over the next solar cycle.

McLean’s folly and the climate clueless Gareth Renowden Mar 13

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In an astonishing press release issued last week, the New Zealand Climate “Science” Coalition predicts that 2011 will be the “coolest year globally since 1956 or even earlier”. The C”S”C bases its prediction on the work of Australian “computer consultant and occasional travel photographer” John McLean. Hot Topic readers will remember McLean as the lead author of a rapidly rebutted 2009 paper (written with Chris de Freitas and Bob Carter) which claimed that El Niño/Southern Oscillation (ENSO) events were a driver of global temperature increases. I covered the full story at the time: see Mother Nature’s Sons and subsequent posts.

One unoriginal finding of the McLean paper was that global temperatures were affected by ENSO events — warming after El Niños and cooling after La Niñas. Last year NZ C”S”C member Bryan Leyland used this to “predict” a coming cooling, which was lapped up by the usual suspects. In January this year, Leyland predicted cooling would continue until at least June. Now McLean has taken this a step further by predicting that temperatures will plunge to that of a cool year 50 years ago. There’s no justification for this prediction in the press release, beyond McLean pretending that his 2009 paper showed that CO2 was a minor player in global temperature change.

Unfortunately for the credibility of all involved, McLean’s prediction is utter unphysical nonsense. Here’s why…

I wanted to find out how McLean’s prediction looked in the context of the long term temperature record, so I downloaded the NASA GISS series data (available here), and plotted it on a graph:

Maclean1956

I’ve shown the 1956 temperature (-0.17ºC referenced to the 1951-80 average) as a blue line. The red cross on the end is where the 2011 temperature would plot if McLean’s prediction were to come true. I also looked through the data series for the biggest single year cooling event. That was a fall of 0.29ºC from 1963 to 1964, helped along by the explosive eruption of Mt Agung in Bali. The higher red cross labelled “1963 cooling” is where 2011 would plot with the same temperature fall. By way of contrast, the largest recent cooling not benefitting from volcanic help was 1998 – 1999, and “only” 0.24ºC.

McLean wants us to believe that global temperatures will fall by 0.8ºC in a single year. There is no precedent for such a large drop in the last 130 years — the variation between years is much smaller, not often exceeding 0.2ºC. The reason for that is easy enough to understand: there’s a lot of thermal “inertia” in the climate system, provided by the oceans that cover 70% of the planet’s surface. The only way global temperatures could fall by 0.8ºC in a single year would be for the amount of solar energy reaching the earth’s surface to be hugely reduced — and the only natural mechanism that could do that would be a volcanic eruption (or series of eruptions) of truly vast size. It won’t happen because of a single La Niña event, however strong and long one might be.

Here’s my prediction. Barring the volcanic equivalent of a nuclear winter, 2011 will probably turn out to be slightly cooler overall than 2010, because of the current La Niña (which may or may not fade away later this year). Given a really steep fall like the one from 1963 to 64, we might have the coolest year since… 2000. That’s what 50 years of heat accumulating the system means. And the underlying warming trend will continue.

You might think that the “scientists” and “experts” at the NZ Climate “Science” Coalition would have noticed that McLean’s temperature forecast is rubbish. After all, they have noted scientists like Bob Carter and Chris de Freitas as members and advisers. Unfortunately Chris and Bob appear to have a bit of a blind spot when it comes to criticising their erstwhile co-author. Meanwhile, the Climate “Science” Coalition, and everyone involved in promoting this sorry little weather forecast are shown, yet again, to be the Climate Cluelessâ„¢.

[PS: I haven't got round to formulating a bet with Bryan Leyland on "warming" v "cooling" (yet), but if he's willing to bet that McLean's right, I'll very happily take the other side.]

[Robert Palmer]

Greasy Heart(land) Gareth Renowden May 21

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And so the party’s over, the tables in the ballroom at the Magnificent Mile Marriot Hotel in Chicago have been tidied up and the carpet vacuumed. The Monckton fan club have drifted away from their vigil in the shade of the trees on the sidewalk outside the lobby, and the speakers assembled from around the world have gone home — except for the ones still waiting in line outside Hot Doug’s for the duck fat fries and andouille special (Fridays & Saturdays only, well worth waiting for, I can assure you).

Luckily for us, however, Heartland are promising to make all the talks available on video, so we won’t have to miss any of the highlights. At the moment they only have the keynotes available, but there are quite a few Powerpoints available for download. I’ve been poking around in some of those…

Bob Carter left the “it’s ENSO wot dunnit” duties to McLean et al co-author Chris de Freitas, and gave a talk on Ancient sea-level & climate change: how do we reconstruct it? Looks pretty interesting and non-controversial, until you get to the last few slides where Carter lets rip:

HCCC4Bob_Carter.017.jpg

Following Nils-Axel “no sea level rise since 1970″ Mörner, and with Fred Singer in the room, I suppose it was inevitable that Bob would downplay the real risks, and give Singer’s Not The IPCC report equivalent billing to real science. Note the green dot for Hansen’s speculation, no doubt there so Bob could get a few laughs at his expense. Meanwhile, out in the real world, Bob Bindschadler’s been in NZ, and told TV NZthe best evidence we have and the best insight into the behaviour of the ice sheet lead us to expect that by the end of the century we are going to see sea levels at least one metre higher than today“. (Pity TV NZ couldn’t spell Bob’s name properly…)

Chris de Freitas devoted his talk to The influence of the Southern Oscillation on mean global temperature, as one might expect from the corresponding author of a controversial recent paper on the subject. Strangely, Chris seems to have ignored the heavyweight rebuttal his paper attracted, and continued to make assertions that are — how shall I put this — tenuous in the extreme. Here’s the text of his last three slides, with annotations:

Summary
Change in atmospheric circulation (ENSO) is a dominant influence on MGT (with 7-month lag).
Mechanism that accounts for this is change in Hadley and Walker circulation
A: During La Niña conditions, zonal circulation of the Walker Circulation is enhanced, whereas the meridional circulation of the Hadley cell weakens; 
B: During El Niño conditions, Hadley, circulation increases, which leads to an increase in heat transfer from tropical to higher latitudes.

So far so good. I might quibble with “a dominant influence”, because his discussion ignores any other potential influences, and McLean et al was criticised for using statistical techniques that overstated the the correlation. But then he says this:

Trends towards high frequencies of B show up as ’global warming’.

Pardon? Is de Freitas really asserting that more El Niños mean more global warming? We’ll have to wait for the video to hear what he actually said, but if he’s true to his slide then he’s wandering a long way off the beaten track. Two big problems with this claim: we have evidence that the ENSO cycle has been operating for a very long time, and there were El Nino events during the cold spells (Little Ice Age) as well as during warmer periods. The second is that when you make a thorough effort to account for all the effects of natural variability in the climate system (see Swanson et al, Long-term natural variability and 20th century climate change, PNAS 2009) you find a strong underlying upward trend. If de Freitas were right, then removing all natural variability would remove all or most of the trend. It doesn’t.

He continues:

Mechanism involves more than simply moving heat around within the global climate system.

Changes in ENSO affect convection, and thus atmospheric moisture content and cloud cover, which may in turn affect net solar heating as well as the transfer of heat from Earth to space.

This is channelling Roy Spencer, as an earlier slide acknowledged. We”l have to wait for the video to see what he means, and how Spencer’s postulated negative (cooling) feedback fits into the more El Niño, more warming framework.

If there was a sustained and significant influence on MGT caused by some other forcing, we would expect to see the temperature line in Figure 7 rising relative to the SOI line. The absence of this divergence implies that increases in atmospheric CO2 have had at most only a small impact on MGT.

This is just risible. de Freitas makes no attempt to quantify this — we’re expected to rely on the Mk 1 eyeball. Perhaps this might be because the temperature data shows a rising trend, and actually showing that would weaken his case? By way of contrast, here’s what Swanson et al found:

Swanson09fig3.gif

The dotted line is the “cleaned” global mean temperature, and as Swanson et al point out, it warms steadily through the century. Back to CdF:

Natural climate forcing of global circulation is major contributor to MGT tendency, a relationship that is not included in current global climate models.

The punch line, and not much of one. As as has been pointed out many times in discussion of the original McLean et al paper, the finding that ENSO has an influence on global temperature is trivial — it’s been well understood for decades. But ENSO events, whatever their frequency, can’t explain the heat accumulating in the system. We may see that demonstrated this year, when the relatively weak El Niño that’s been around for the last six months could drive the global temperature above the levels seen during the strong El Niño of 1998. de Freitas is also wrong about climate models. The better ones certainly do show ENSO cycles — not perfectly, but they’re there. Knocking climate models is a core feature of the crank catechism, and when on a pilgrimage to crank central I suppose you have to observe the ritual responses.

I’ve also has a look at Bryan Leyland’s presentation on renewable energy, A $720 billion boondoggle? Bryan’s answer is straightforward enough (yes, of course), but his talk is chiefly notable for his optimistic take on fossil fuel availability:

HCC4Bryan_Leyland6.006.jpg

The words “cloud cuckoo land” spring to mind. Bryan believes that global warming is “a problem that doesn’t exist”, and so he is therefore free to burn as much carbon as he wants. Not what I’d call strategically sound advice…

Finally, one presentation at the Heartland conference I can heartily recommend was made by Scott Denning, professor of atmospheric science at the University of Colorado. Scott was one of only two non-sceptic climate scientists to accept an invitation to talk, and his Debunking common myths about global warming is a very straightforward explanation of why we have a problem. He was applauded for his bravery, as you can see over at In It For The Gold. It’s also worth having a look at Richard Lindzen’s extraordinary speech in which he accuses climate scientists of “overt cheating”. I’d give Monckon’s conference closer a miss though. Having sat through more than one of his speeches in the interests of research, I can confirm that’s he’s running low on jokes. You’ve used ‘em all before, Chris.

[Jefferson Airplane]

Carterist science meets its Cartergate Gareth Renowden Mar 22

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homer.jpgThe peer-reviewed rebuttal to last year’s infamous McLean, de Freitas and Carter paper which claimed that the El Niño Southern Oscillation could explain most recent warming (see Mother Nature’s Sons and Big Guns Brought To Bear), has been accepted for publication by the Journal of Geophysical Research (Comment on ’Influence of the Southern Oscillation on tropospheric temperature’ Foster et al, 2010). Co-author James Annan has the details (and full text of the rebuttal), but what is perhaps most remarkable is that despite being given the opportunity to reply to Foster et al’s comment — normal practice in these circumstances — McLean et al’s offering has failed to pass review and will not be published by JGR. Tim Lambert at Deltoid has more feedback, and draws attention to the comments by Prof Ove Hoegh-Guldberg at Climate Shifts who demands:

The five things we want to know are:

  1. Will McLean et al. retract the paper (and will Bob Carter admit fault or even discuss the errors publicly)?
  2. Will the denial0sphere and the MSM give this story (a climate change scandal!) the same coverage it has recently showered on various IPCC hiccups?
  3. Will there be an investigation as Bob Carter himself and so many other skeptics have insisted on over and over again, usually in response to bogus and unsubstantiated allegations.
  4. Will Bob now reverse his policy positions and urge (vocally) politicians that may have been swayed by his bogus science to do the same? After all Bob, shouldn’t the science drive the policy?
  5. Will The Australian cover this pending scandal! A scientist behaving badly!

Those look like damned good questions to me. New Zealand’s science community has been reluctant to publicly criticise Carter — he was once a respected and influential scientist who encouraged many talented students to forge their careers in the earth sciences — but surely this display of academic turpitude puts him beyond the pale. What it says about de Freitas is probably unprintable. I encourage readers to remember the extravagant claims being made for this paper by Carter and de Freitas, and the uncritical acceptance of those claims by a pliable media. High time the boot was on the other foot.

[This song's for Bob: h/t caerbannog in comments at Deltoid]

[Update 23/3: Skeptical Science explains the rebuttal here. Worth a read.]