SciBlogs

Posts Tagged cooling

Bob Carter: innumerate and irrational? Gareth Renowden Mar 11

Join the conversation at Hot Topic

Bob Carter, in Shhsshh … don’t talk about the science, Quadrant Online, Feb 28 2011:

So what about the famous global warming which occurred in the late 20th century, whatever happened to that? Well, not only did the gentle warming terminate in 1998, but in accord with natural climate cycling that warming has been followed by a gentle cooling since about 2001. That’s ten years of no temperature increase, let alone dangerous increase, over the same time period that atmospheric carbon dioxide increased by about 5%.

Run that past me again, Professors Garnaut and Flannery — your advice to government still remains that human carbon dioxide emissions are causing dangerous global warming?

Ross Garnaut, in his introduction to the Garnaut Climate Change Review — Update 2011, Update Paper five, March 10 2011: The science of climate change, after noting that statisticians confirmed (again) the presence of a warming trend in the latest data:

The statistical evidence did not stop assertions in the public debate that the earth was cooling, but it does seem to have discouraged at least the numerate and rational from repetition of errors into which they had carelessly fallen.

So where does that leave Carter, I wonder? I think we can rule out his being careless in the presentation of the facts. And he can’t really be innumerate — the Royal Society of New Zealand does not welcome the mathematically challenged to its ranks. Irrational? How else do you describe someone who argues the exact opposite of the truth? What’s the term I’m striving for? Is he being economical with the truth or simply telling lies? I leave that for the reader to decide.

The Climate Show #3: Cancún and cooling Gareth Renowden Dec 02

Join the conversation at Hot Topic

Climate talks heat up in Mexico, snow blankets Britain and much of Europe, and The Climate Show is at the heart of the action. Glenn and Gareth set the scene for COP16 in Cancún and then interview Oxfam NZ’s Barry Coates at the conference to find out how things are shaping up. Gareth explores the link between Arctic climate change and cold winter weather in Western Europe, John Cook debunks that favourite sceptic myth — that the world’s cooling — and we look at the potential for nuclear power to provide part of the solution to decarbonising the power economy.

Watch The Climate Show on our Youtube channel, subscribe to the podcast via iTunes, or listen direct/download here:

The Climate Show

Follow The Climate Show on Facebook and Twitter, and soon at The Climate Show web site.

Show notes below the fold.

Drought in the Amazon: see Bryan Walker’s recent post I wish it would rain, and a good Reuters feature here.

Snow in Britain and Europe: pictures and news at the BBC.

NOAA’s Arctic Report Card on WACCy weather here.

UK Met Office statement, Nov 30.

Temperature anomaly

201011NZtempanomaly.gif

(plotted at NOAA’s ESRL Daily Mean Composites page)

Normal NH atmospheric circulation at this time of year (850mb geopotential height climatology)

201011NH850climo.gif

Current atmospheric circulation

201011NH850actual.gif

(plotted at NOAA’s ESRL NCEP reanalysis page)

Cancun starts – expectations low: Can Cancún’s COP deliver?

Copenhagen Accord sets the world on a path to 3C: (2) Degrees of existence.

…or perhaps 4C: RS Journal special issue – Four degrees and beyond: the potential for a global temperature increase of four degrees and its implications, and Guardian report.

UNFCCC iPhone app, Negotiator.

Barry Coates at Oxfam NZ: blog, new report, Now More Than Ever: Climate talks that work for those who need them most.

Give a goat for Christmas.

Debunking the skeptic with John Cook from Skeptical Science. This week: Global Cooling.

The Many Parts Solution

Going nuclear: new power station in Finland – ’many of the engineers and building experts working here are in their late 50s and early 60s; some are in their 30s, but few are in between. There’s a hole in the nuclear workforce, not just in Finland but across the Western world.’ — Reuters special report.

Nuclear is certainly part of the solution, for good coverage of a key technology – ’fourth generation’ integral fast reactors – see Prof Barry Brook’s excellent Aussie blog Brave New Climate.

Smaller scale: LED lightbulbs approaching mass market — 60 watt replacement due soon.

Thanks to our media partners: Celsias.co.nz and KiwiFM.

Theme music: A Drop In The Ocean by The Bads.

Whose lie is it anyway? Easterbrook caught red-handed Gareth Renowden May 30

Join the conversation at Hot Topic

Don Easterbrook was forthright in his attempt to rebut my discovery that he had used an edited version of a graph of Holocene temperatures originally prepared by Global Warming Art in his recent Heartland conference presentation. He accused me of telling a “dispicable” lie, amongst other things:

The charge by ‘the truffle grower’ that I used a graph “prepared by Global Warming Art” and that I “altered it to fraudulently bolster his case” is an outright, contemptible lie. I have the entire Greenland oxygen isotope data in my computer and use it extensively to plot data, so why would I use anything else? The data I use has never been altered in any way.

Unfortunately for Easterbrook, his own web site contains material that proves he is the one telling “outright, contemptible” lies, and defaming me in the process. Here’s why…

Diligent digging at Easterbrook’s web site by Hot Topic reader Glacier Guy unearthed the Powerpoint file for a presentation Easterbrook gave to the annual meeting of the Geological Society of America in Denver in October 2007 (go to Easterbrook’s Western Washington University page, download the pdf of the abstract to the talk entitled Geologic evidence of recurring climate cycles and their implications for the cause of global warming and climate changes in the coming century and you’ll find a link to the .ppt file there — but to save the effort, I’ve provided a direct link above). Here’s Easterbrook’s slide 17 from that talk. Readers who have been following cooling-gate will find it looks familiar:

DE07GWA1.017.jpg

Similar to the GWA original, is it not?:

GWAHolocene.jpg

As is obvious, when preparing his 2007 presentation he couldn’t be bothered to get rid of all the temperature proxy “spaghetti” lines from Robert Rohde’s original. He just took out the inset showing “recent proxies”, drew a new baseline (based, by the look of it on an attempt to replicate the 1905 “present” he prefers to use), and labelled the Medieval Warm Period and the Little Ice Age.

By the time of the Heartland conference, however, he’d done a little tidying up and helpfully labelled his new (and entirely fraudulent) baseline:

Easterbrookholocene.009.jpg

The genesis of Easterbrook’s slide at the Heartland conference is clear. He “borrowed” the Global Warming Art graph in 2007 (if not earlier), and made some crude alterations to it then. Over the years, he has refined the presentation somewhat, but compounded the fraud. That he was familiar with GWA as a source of graphical material is also confirmed by his 2007 presentation, because slide 18 is a direct lift of this GWA graph of recent temperature proxy reconstructions, edited by the removal of a data point labelled “2004″. Ring any bells?

It is quite clear from the evidence that Easterbrook has not only edited these graphics to change the information they contain, but done so in order to minimise the appearance of recent global warming and to support his own oddball contention that global cooling is about to begin. This is at the very least academic malpractice, particularly by such a distinguished professor emeritus. It might be interesting to discover what the Western Washington University thinks of his behaviour. It is also clear that his aggressive, failed attempt to rebut my original post is defamatory, as is the rush to republish his remarks by other web sites. It would be nice if Easterbrook issued a public apology to me and to Global Warming Art, but I will not be holding my breath while waiting for it to arrive. Meanwhile, the silence from the climate sceptic echo chamber about the scandal in their ranks is becoming deafening.

Cooling-gate: the 100 years of warming Easterbrook wants you to ignore Gareth Renowden May 27

Join the conversation at Hot Topic

Evidence that Don Easterbrook did more than misrepresent and alter a graph in order to remove evidence of recent warming in his presentation to the recent Heartland “climate conference” is beginning to emerge. It now appears that he has been misusing one of the most important paleoclimate temperature data series, compiled from the GISP2 Greenland ice core, effectively hiding a full 100 years of recent warming. His “rebuttal” of my revelations that he had misused a graph from Global Warming Art includes this assertion:

…below is the Greenland data for the past 10,000 years (Holocene) from the published paper by Cuffy and Clow (1997), two distinguished US scientists. Note that temperatures for almost all of the past 10,000 years have been warmer than present.

In my post yesterday, I suggested (on the basis of the notes accompanying the raw δ18O data), that the “present” Easterbrook was referring to was 1950. It now appears I was being far too generous. Thanks to a bit of detective work by MartinM in the comments to that post, the data set used by Easterbrook to draw his version of a Holocene temperature graph turns out to be the temperature series derived from the δ18O data by Richard Alley: Alley, R.B. 2004. GISP2 Ice Core Temperature and Accumulation Data. IGBP PAGES/World Data Center for Paleoclimatology
Data Contribution Series #2004-013. NOAA/NGDC Paleoclimatology Program, Boulder CO, USA
(ftp download here). The most recent temperature data point in that series is 1905, and that’s the point Easterbrook labels as the present. To make his case he has to make a full century’s worth of warming disappear.

I downloaded Alley’s data and plotted it with my new favourite graphing tool. This is what it looks like:

GISP2graph

I’ve inset the graph from Easterbrook’s “rebuttal”, and added a couple of helpful lines (click for a bigger version). I think it’s pretty clear that the data behind both graphs is the same. There’s more detail in my plot, but the key features are all in the right places. I’ve added a blue line to represent Easterbrook’s “present temperature”. The green line represents an estimate of current temperatures in central Greenland. I looked at the nearest station with a 100+ year record in the GISS database (Angmagssalik), and used a Mk 1 eyeball to estimate a 2.5ºC increase over the century (I’d welcome a more accurate estimate, if anyone’s prepared to dig one up). The difference between the green and blue lines is the warming that Easterbrook wants to ignore. His statement that temperatures for almost all of the past 10,000 years have been warmer than present is shown to be complete nonsense. There are three points in the last 10,000 years when temperatures high up on the Greenland ice sheet were similar to today, but by no stretch of anyone’s imagination can it be said to have been warmer for most of the time. The incline he’s trying to hide is one of the largest and steepest in the last ten millenia…

The same temperature series also appears to form the basis for Monckton’s famous “Curry & Clow” slide from early 2009:

Monckton credits the wrong people, of course, but adds a helpful “300 years of warming” arrow. Like Easterbrook, he omits the last 100 years of warming. This is what he said at the time:

Seen in the geological perspective of the last 17,000 years, the 300 years of recent warming, nearly all of which must have been natural, for we could not have had any significant influence except in the past 25 years, are manifestly insignificant.

The 300 years of recent warming are of course the 300 years up to 1905. What has happened since then is manifestly significant. This sort of misdirection is par for the course for Monckton, but what about Easterbrook?

If he knowingly misrepresented 1905 as the “present” (and given that he claims to have “the entire Greenland oxygen isotope data in my computer and use it extensively to plot data” that has to be a real possibility), then he is clearly misusing the data and misleading his audience. The intellectual dishonesty involved is breathtaking. His audience may want to be mislead, but that is irrelevant. On the other hand if, as a distinguished academic with a long career studying (amongst other things) glaciers and climate change, he really doesn’t know that the data series stops in 1905, then he is demonstrating ignorance of a sort that would embarrass any student.

So where’s the investigation of this academic fraud? Where are the hordes of bloggers and journalists screaming blue murder about the manipulation of data to tell a convenient story? Here’s Joseph Bast, president of the Heartland Institute, writing about the so-called “climategate” affair last November:

Looking at how past disclosures of fraud in the global warming debate have been dismissed or ignored by the mainstream media leads me to suspect they will try to sweep this, too, under the rug. But thanks to the Internet, millions of people will be able to read the emails themselves and make up their own minds. This incident, then, will not be forgotten. The journalists who attempt to spin it away and the politicians who try to ignore it will further damage their own credibility, and perhaps see their careers shortened as a consequence.

How very true. I look forward to Bast issuing a statement apologising for being a party to Easterbrook’s fraud, for providing him with a platform to mislead and misinform, and instituting an in-depth investigation into the background of Cooling-gate. But I suspect he will be doing his best to ignore the whole affair. I leave it to the reader to decide what that does for the credibility of Bast, Heartland, and the scientists who shared a stage with Easterbrook at Heartland’s Chicago conference.

[Update 29/5: My graph revised and improved, see comment below]

Cooling-gate: Easterbrook defends the indefensible Gareth Renowden May 25

Join the conversation at Hot Topic

Don Easterbrook seems to have decided that when under pressure, attack is the best form of defence. He’s replied to my original post and Tim Lambert’s added exposure of his statistical sleight of hand in this document (pdf)apparently composed as a reply to a query from Andy Revkin of the New York TimesDot Earth blog. Here’s how he ends his piece (it’s all in caps because that’s the way it is in his document, and I wouldn’t want to alter the data…):

CONCLUSION — THE ‘FAKE DATA’ CHARGE BY THE ‘TRUFFLE GROWER’ IS A COMPLETE LIE–THE DATA COMES FROM THE WORLD STANDARD OXYGEN ISOTOPE RECORD FROM THE GREENLAND ICE CORES, AND THE RECENT TEMPERATURE DATA IS FROM SATELLITES. ALL OF THIS DATA IS EASILY AVAILABLE FOR ANYONE WHO WANTS TO PLOT THEIR OWN GRAPHS. THE CHARGE THAT THIS DATA HAS BEEN ALTERED IS A DISPICABLE LIE.

Unfortunately for Easterbrook’s credibility, all he’s done is confirm his own mistakes. He not only attempts to defend the wrong graph, but confuses me with Tim Lambert and underlines the considerable statistical naivety in his analysis of recent global temperatures. To make matters worse, a pixel-by-pixel comparison of Easterbrook’s slide nine and the Global Warming Art equivalent shows that they are a perfect match — confirming my original charge: that Easterbrook had crudely altered the GWA original to better suit his storyline.

Easterbrook’s reply is a classic of its kind. A blustering, intemperate attempt to defend the indefensible, he only manages to dig himself into deeper trouble. Here he goes:

The charge by ‘the truffle grower’ that I used a graph “prepared by Global Warming Art” and that I “altered it to fraudulently bolster his case” is an outright, contemptible lie.

Here’s an overlay of Easterbrook’s slide nine on the GWA original, prepared by HT reader and Photoshop expert Bill Doyle:

easterbrook-vs-GWA480.jpg

Bill describes the uncanny similarities in a comment to my original post:

I await with interest the explanations that account for its not only being in the same position as the zero line in the GWA graph, but that – even the bloody grey dashes are in the same places!

And there are the faint pixels that just happen to be faded versions of the same same colours as GWA’s original ’spaghetti’!

And if that wasn’t enough, try examining the extreme lower right and upper right hand corner of the graph. Along the x-axis – the time scale – the ‘0′ – present time – is not flush with the right-hand margin of the chart – it’s offset by a couple of pixels. This anomaly is identical in both charts!

‘Uncanny’ is a word that comes to mind! As is ‘busted’!

In other words, there can be no doubt that Easterbrook used a crudely edited version of the GWA graph in his presentation. I am not the liar — he is. He then moves on to defend the wrong graph:

This is totally false — below is the Greenland data for the past 10,000 years (Holocene) from the published paper by Cuffy and Clow (1997), two distinguished US scientists. Note that temperatures for almost all of the past 10,000 years have been warmer than present.

Let’s set aside Easterbrook’s misspelling of Kurt Cuffey’s name: the full reference to Cuffey and Clow 1997 is Cuffey, K.M. and G.D. Clow (1997). Temperature, accumulation and ice sheet elevation in central Greenland through the last deglacial transition. Journal of Geophysical Research 102(C12), 26383-396. Regular readers will know that I had occasion to delve into that paper when investigating some Moncktonian nonsense, so what it says is not unfamiliar to me. It’s also possible to download the underlying data and graph it yourself — in fact it is one of the temperature series used in the Global Warming Art graph (but only one). Here’s Easterbrook’s plot from his “reply”:

EasterbrookGISP.jpg

Once again, he provides a baseline and labels it as present temperature, and pace Monckton, provides a helpful arrow to “present global warming”. I assume for the sake of argument that Easterbrook is telling the truth when he says his new graph is based on the GISP2 data, but he continues to hide the incline. Here’s one of the notes in the datafile:

(3) layer count ages at top depths (in yr BP) where 0 BP represents AD
1950 SUMMER to AD 1949 SUMMER

“Present” is therefore defined nice and accurately at 1950. Given what we know of global and regional temperature changes over the last 60 years, I think we can assume that Greenland has warmed. In fact there’s no need to assume anything: NASA’s GISS helpfully provides a summary. In the region where the core was drilled, there has been warming of around 1ºC. There’s no scale on Easterbrook’s graph, so it’s not clear how far above his baseline that would be — but it does suggest that his definition of “present” is not one that most people would use.

There’s another problem with his use of the Greenland ice core data. He wants it to stand as a proxy for global temperature. It isn’t. It’s a record of temperatures high up on the summit of the Greenland ice sheet. Most of the rapid changes of temperature seen in the core, and which Easterbrook analyses in great detail, are not seen in Antarctic cores, for instance.

Easterbrook’s next step is to confuse me with Tim Lambert, who is not, so far as I know, a truffle grower (though I would be glad to offer free advice should he wish to join the burgeoning Australian truffle industry). I’ll leave it to Tim to reply to that section, but it should be obvious that Easterbrook is ascribing far too much significance to short term temperature trends. The other side of the “no statistically significant warming for 15 years” coin is that there can’t be statistically significant cooling either…

Let’s return to Easterbrook’s conclusion.

THE CHARGE THAT THIS DATA HAS BEEN ALTERED IS A DISPICABLE LIE.

It is clear beyond all doubt that Easterbrook used an edited graph from Global Warming Art in his Heartland presentation, and has trouble with his spelling. His attempted defence of his position makes him look a lot more like one of Richard Lindzen’s “overt cheats” than it does an academic defending his reputation. And guess what? No sign yet of any contrition from the sceptic camp, just a few pathetic attempts at spin in the comments here. Tells us all we need to know…

*****

PS: I find it interesting that when people respond to posts here they choose to characterise me as a “truffle grower” or “trufflehunter”. In Easterbrook’s case, he calls me a “photographer and truffle grower”, a description he may have borrowed from my Linked-In profile. He’s been cherry-picking there too. The full description is “writer, photographer and truffle grower”, and I’ve been writing professionally a lot longer than I’ve been growing truffles…

Cooling-gate! Easterbrook fakes his figures, hides the incline Gareth Renowden May 21

Join the conversation at Hot Topic

Don Easterbrook, the retired geology professor who predicted that the world was headed for decades of global cooling at the recent Heartland climate sceptic conference, appears to have crudely faked one of the key graphs in his presentation in order to reduce modern temperatures and make historical climate look warmer than justified. Looking through Easterbrook’s slides, it seems he has taken a graph of Holocene temperature variations prepared by Global Warming Art (used at Wikipedia), and altered it to fraudulently bolster his case.

Here’s Easterbrook’s graph (slide 9, ppt file available here):

Easterbrookholocene.009.jpg

When I saw that graphic, it struck me as strangely familiar. The typefaces and presentation are reminiscent of graphs prepared by Robert A Rohde for Global Warming Art. So I checked, and this is what I found:

GWAHolocene.jpg

Here’s the source page. Note that the typeface and scaling of the axes are identical, save for the y-axis being swapped over to the left. The thick black curve, the median of the reconstructions Rohde has used, is identical. Here’s a “blink” comparison:

GWAHoloceneanim.gif

Easterbrook has altered the graph considerably. The dotted line across the graph marks the zero anomaly, which Rohde has set at the mid-20th century average values. To put current temperatures in perspective, he has provided an arrow indicating 2004’s temperature and a box providing an expanded scale for the last 2000 years. Easterbrook has erased that arrow, all the individual reconstructions and the detail box, and drawn a new line at 0.25ºC below zero. This he labels “present day temperature”. Areas above the new line are infilled in red, those below in blue. Easterbrook has quite deliberately altered the graph to reduce “current temperatures” by 0.75ºC and make the curve fit his storyline. The original suggests that current temperatures are comparable to, perhaps higher than the warmest period of the Holocene, the post-glacial climatic optimum 8000 years ago. Easterbrook’s version gives the impression that for most of the last 10,000 years temperature has been warmer than today. It’s interesting to note that Easterbrook has added a pointer to the Younger Dryas, but has managed to misspell it “Dyas”.

The hypocrisy inherent in Easterbrook’s approach to scholarship is shown in sharp focus by his slide 15, in which he discusses “Climategate”:

Easterbrook15.015.jpg

What has Easterbrook done? He has constructed a climate history that exaggerates the Medieval Warm Period, doctored climate data to suppress global warming and increase global cooling, and deleted data that doesn’t support his beliefs. The climate change fraud is Easterbrook.

This is a telling moment for the Heartland group of “sceptic” scientists and lobbyists. They have been loud and persistent in their attempt to demonise the scientists whose emails were stolen from the Climatic Research Unit at the University of East Anglia. Richard Lindzen has gone so far as to accuse them of “overt cheating”. If they do not now demand an immediate apology from the cheat in their own midst, and withdraw and apologise for their promotion of his flawed scholarship, then they will stand revealed as a bunch of hypocritical charlatans. Either you live by the standards you demand of others, or you shut up. I look forward to the detailed coverage of Easterbrook’s cavalier approach to evidence from Watts Up With That, Climate Audit, Delingpole at the Telegraph and Leake at the Sunday Times. But I won’t be holding my breath.

Wake of the flood Gareth Renowden Apr 11

Join the conversation at Hot Topic

About 15,000 years ago the world began to warm out of the last ice age. The huge ice sheets that covered North America and Northwest Europe began to melt, and sea level began to rise. But 12,900 years before present, the climate of much of the northern hemisphere made a rapid return to full ice age conditions — cooling by as much as 10ºC. The Big Freeze, as it’s sometimes called, could have started in as little as one season. The cold snap lasted 1,300 years before warming resumed and the current interglacial began. This cooling episode is known as the Younger Dryas, because it was associated with an increase in pollen of the Arctic plant Dryas octopetala in Norwegian lake sediments.

The cause of this sudden climate flip has been hotly debated, but the most widely supported theory was first advanced by oceanographer Wally “climate’s an angry beast” Broecker in 1989. He suggested that an outburst of meltwater from the lakes forming as the Laurentide Ice Sheet shrank could have changed ocean currents in the North Atlantic. A sudden and massive influx of fresh water could have capped the sinking of cold water in the far north, switching off the process that draws warm currents up towards the Arctic. Sea ice would have been able to form much further south, reaching down to the British Isles, and ice age conditions would have returned to North America and Europe.

Broecker’s idea was that a massive glacial lake called Lake Agassiz could have drained to the east, down the St Lawrence and out into the Atlantic, but geologists have had trouble finding evidence for the size of flood that would have been required. It has been calculated that the lake lost around 9,500 cubic kilometres of water in the outburst. Now geological detective work by a team lead by Julian Murton of the University of Sussex has discovered evidence for a flood of the right size and the right time, but heading due north into the Arctic Ocean via the McKenzie River system [Science Daily, University of Sussex].

Dryas1.gif

This map from Murton et al’s paper in a recent issue of Nature (Murton et al. Identification of Younger Dryas outburst flood path from Lake Agassiz to the Arctic Ocean. Nature (2010) vol. 464 (7289) pp. 740-743) shows the lie of the land at the time. The ice sheet was centred over Hudson’s Bay, and great lakes (some of them now Great) formed around its southern and western flanks as it melted. If you’re interested in this sort of geological and climatic detective work, it’s well worth reading the paper, but if you don’t have access this Nature News item gives a good overview of Murton et al’s work.

The great flood might be the most plausible mechanism for the trigger of the Younger Dryas cooling, but that hasn’t stopped other mechanisms being suggested. In recent years it has been proposed that a comet could have smashed into the Laurentide ice sheet causing catastrophic melting, but that idea hasn’t received much support from climatologists. The comet idea won’t lie down, however, and as Murton et al’s paper was hitting the presses, Professor Bill Napier of the University of Cardiff’s Astrobiology Centre was suggesting that the cooling could have been brought about by massive wildfires caused by the impacts of thousands of pieces of a cometary tail. The Daily Telegraph helpfully described it as “an hour long hailstorm from space“. For what it’s worth (which is not much), my money’s on the flood.

[Grateful Dead]

…Keep out of the kitchen Gareth Renowden Oct 20

Join the conversation at Hot Topic

It appears that Ian Wishart is back on the climate beat, with a couple of posts in the last week attacking Hot Topic. One goes so far as to accuse me of incompetence and dishonesty, which is a bit rich coming from someone who was threatening to sue me for libel a few months ago… Anyway, his latest offering attempts to chastise me for stating in a comment that global temperatures were not falling. That gives me a welcome opportunity to post on the subject and introduce a nifty little gadget programmed by a Hot Topic reader. Here’s Wishart:

Virtually all the major datasets are now acknowledging atmospheric warming has slowed to a crawl or stopped over the past ten years, and even some leading climate alarmists scientists are publicly suggesting we’ve entered a climate shift and may not see warming return for a further decade or more. The data clearly shows temperature anomalies trending down despite CO2 emissions rising:

He appends a graph of UAH monthly temperature anomalies from 2002 to some point earlier this year, with a descending trend line. Lo and behold, “cooling”!

Over seven years, this data set suggests that global temperatures are falling. The problem, however, is that climate is not measured over seven year periods, and there’s a very good reason why. The climate system is ’noisy’ — natural variations in the ocean/atmosphere system such as the El Niño Southern Oscillation or volcanic eruptions mean that global temperatures go up and down a fair bit, so if you want to know about any underlying trends you have to look at a period of time long enough for the ’ups’ and ’downs’ to cancel out. That’s usually taken to be 30 years — the World Meteorological Association’s standard period for defining climate statistics.

Now for the nifty gadget. Hot Topic reader Colin Sharples (aka CTG) is a whizz with Javaâ„¢ programming. Prompted by a discussion on climate trends at ReaClimate, he took NASA’s GISS global temperature dataset (to be precise, it’s the GISTEMP series for the climatological year (Dec-Nov) and he’s estimated a figure for 2009 by ’completing’ the year by calculating the average anomalies for the last few months of the year over the last five years) and the Hadley Centre’s HadCRUTv3 series and produced an interactive graphic that shows how changing the length of the period you select for trend calculations affects the trends you see. Here it is:

The slider at the bottom starts at 30 years — the standard period for climate stats. Choose between data series with the button at the top. Blue lines show negative trends, red ones positive trends, calculated for each successive 30 year period. In the GISTEMP series you can see some falling trends in the 1880s and 90s, and again from the 1940s to 70s. The rest of the time, temperatures are rising. No sign of cooling in the 21st century.

Now try moving the slider to 20 years. There’s a bit more blue in the early years, but things look pretty similar to the 30 year trends. At 15 years, a couple of brief ’warmings’ appear in the previously cooling sections, but the most notable feature is that some of the trend lines become a lot steeper — there is faster warming and cooling appearing in the graph. With the slider at 10 years, not only do the trend slopes become even steeper (look at the ’warming’ in the 1890s!), but bits of spurious warming and cooling appear. There are a couple of blue lines in the late 1980s to mid-90s, the first episodes of ’cooling’ to show up over the last 40 years, but still no cooling to be seen in the last ten years. You have to wind the slider back to a seven year period before you get a cooling trend line in the 21st century. Just the one. And there’s still only one if you stick the slider at the minimum period of five years.

If you look at the big picture, using such a short period means that the trends oscillate up and down as global temperatures move and up and down. They’re reflecting the noise in the system, not the underlying trend — and when we’re discussing global warming we’re interested in the long term trend, not the ups and downs. Woodfortrees also provides a clear demonstration of the dangers of playing with short term trends here, using the UAH satellite temperature data.

That’s the central fallacy of Wishart’s assertion that warming has ’stopped or slowed to a crawl’ despite CO2 continuing to rise. It’s a claim you can only make by choosing very short timescales, and ignores the fact that the change we’re interested in emerges over periods of decades, not year to year.

The rest of Wishart’s long post is tortuous and unclear. He appears to be arguing that because one paper has found that aerosols and dust have an impact on the rate of ocean warming in the North Atlantic that this somehow downplays the effect of greenhouse gas forced warming. He says, for instance, that ocean warming is ’mainly solar driven depending on atmospheric clarity’. But all warming is ’solar driven’ — that’s where the heat’s coming from. Dust, aerosols and greenhouse gases change the rate at which it’s absorbed by the system. And by the way, the last time I looked at a map, the North Atlantic was only a small part of the global ocean, and can’t be said to be typical of the whole.

Even his conclusion is muddled:

Get real, Truffle. The atmospheric temperature anomaly is trending down, the oceans are not displaying significant signs of heating, and some of your cheerleaders are admitting it’s not so hot right now. I’m sure warming will return, but this is good evidence of strong natural cycles at play.

So warming’s going to return because it will overcome those strong natural cycles? Sounds reasonable. Perhaps Wishart’s been following the monthly temperature figures at NOAA, which has August 2009 as the warmest in the record, and September as the second warmest. Looks like the warming’s already back. Because, of course, it never went away.

My thanks to Colin for allowing me to embed his GISTEMP Java applet. It may also appear in other places and in enhanced form in due course, but remember where you saw it first… ;-)

Carter, the unstoppable text machine Gareth Renowden Sep 29

Join the conversation at Hot Topic

homer.jpgBob Carter’s writing style (logorrhea, leavened with pomposity) is on display once more at Quadrant Online, and this week’s missive from planet Bob — headlined Media Ecoevangelists – finds him fulminating about an ABC documentary on the future of coal, The Coal Nightmare. I can’t comment on the film, it not having screened over here so far as I can tell, but I can question a few of Bob’s wilder assertions…

It is a commonplace that the mainstream media distort the public debate on environmental issues of the day.

A case in point is the continuing uncritical alarmism about allegedly human-caused global warming, at a time when the globe has been cooling for ten years and human causation remains chimerical.

Chimerical! Fine word. A pity then that it should be so misused. Let’s pass over his repetition of the ’cooling’ trope (except to ponder that perhaps he’s using it as often as possible before a new global temperature record makes repetition of that inaccuracy untenable even for him), and concentrate on the causation. CO2 in the atmosphere has increased by 40% in the last 150 years, and that increase has been caused by human activity (see here for a recent discussion). Is Bob really asserting that the CO2 increase is not from human agency, or does he mean something else? In what way is human causation a chimera? Our fingerprints are all over the place…

But it’s the media that are his real target:

The Fairfax press, together with public broadcasters ABC and SBS, furnish egregious examples of this on a regular basis as they dutifully promulgate — without a trace of critical analysis — the unrestrained, apocalyptic imaginings of the many scientific, environmental and business lobby groups who are now poised to benefit from a carbon dioxide taxation system (aka emissions trading scheme; ETS).

Sounds like sour grapes to me. Perhaps because Bob’s unrestrained apocalyptic imaginings about the costs of action are not finding as wide an audience as in days past.

One was reminded irresistibly of the famous, scientifically illiterate first sentence of Climate Minister Wong’s Green Paper on emissions trading last year, which contained no fewer than seven basic errors.

One is reminded irresistibly that the ’seven errors’ were enumerated by none other than Carter himself in an article in The Age (no ecoevangelism there, apparently). Yes, it’s turtles all the way down

Bob’s key argument:

In fact, the reality is precisely the opposite of the conventional wisdom that our ABC so doggedly pursues in this film and elsewhere, and it is that carbon dioxide emissions are an environmental benefice.

Another good word! But benefice, really? Yes, says Bob:

First, because at current and near-future levels the emissions do not cause dangerous warming (though they may yet prove to confer a just measurable mild warming that would help offset the current planetary cooling trend). And, second, carbon dioxide being effectively an aerial fertilizer for plants, because rising levels in the atmosphere during our modern geological time of carbon dioxide starvation provide a significant boost for plant productivity, and hence food supply.

Two points, Bob. Ocean acidification. And the Eemian. The first is important, because even if increasing atmospheric CO2 were not a problem in its own right, then the effect of increasing quantities of CO2 dissolving in the world’s oceans is quite enough on its own to make emissions reductions prudent, even essential. (See the UNEP Compendium report for a recent overview, pp29-35). During the last interglacial, 125,000 years ago, CO2 levels topped out at about 300ppm, the world was a little warmer than today, and sea levels up to 5m higher. So what was that about ’current and near-future levels’ Bob? We’re already at 389ppm and rising. I don’t know about you, but I would think a certain caution was advisable, eh?

The rest of Bob’s article is a lengthy diatribe meant to demonstrate that coal is not dirty, carbon dioxide not a pollutant and that the Aussie media is under the control of Deep Greens. Let’s leave him with this:

The business community would not for one moment put up with the business section of the daily news being presented in the incompetent and partial way that today typifies press coverage of environmental issues. And neither should the scientific community allow its hallowed standards of objectivity, impartiality and falsification testing against empirical data to be traduced, as they regularly are, in the reporting of environmental and related scientific issues.

If only Bob Carter applied those same hallowed standards to his own output, for in this case Bob’s pot is in imminent danger of colliding with Carter’s kettle. And what was that about empty vessels..?

[The Only Living Boy In New Cross]

The biased leading the blind Gareth Renowden Sep 25

Join the conversation at Hot Topic

homer.jpgTwo of New Zealand’s most prominent climate cranks, “inexpert witness” Chris de Freitas and Bob “great communicator” Carter are no strangers to the art of misrepresenting facts in support of their peculiar political visions, but recent articles by the pair set new standards for economy with the truth. Here’s De Freitas, writing in Energy NZ:

…no one has yet found even a shred of objective scientific evidence that humans are causing damaging global climate change.

No to be outdone, in Aussie “journal of ideas” Quadrant Carter revives the oldest zombie fact of them all:

As the temperature trend for ten years now has been one of cooling, since the unusually warm El Nino year of 1998, this requires a precautionary response to cooling rather than warming.

De Freitas’ piece is — even to my jaundiced eyes — remarkable for how liberally he misleads his readers…

Fit the first:

In preparation, the Government has committed New Zealand to cut up to a third of current emissions by 2020.

The economic, social and moral implications are immense, since carbon taxes and tradable emissions alone cannot make such a massive reduction. Sweeping legislation restricting the use of oil, coal and natural gas would be required, along with far-reaching reforms in pastoral farming to cut methane release.

De Freitas is ignoring the fact that any 2020 target will be for net emissions, that is, emissions after taking into account the carbon stored away in New Zealand’s growing forests. The government is aiming to weaken the emissions trading scheme, but still apparently expects forestry to play a major role in helping NZ to meet the target. But de Freitas prefers to spin a scary fairy tale…

Second fit:

…no one has yet found even a shred of objective scientific evidence that humans are causing damaging global climate change.

Breathtaking in its ignorance. But he continues:

There are no published scientific papers that show irrefutable proof of human-caused global warming.

Oh really? Depends what you mean by irrefutable, I suppose. There’s a very large attribution literature, handily summarised in Chapter 9 (PDF) of the WG1 report in IPPC’s Fourth Report (AR4). It starts: Human-induced warming of the climate system is widespread, and references approximately 550 papers. Either de Freitas has read them all and prepared detailed rebuttals, or his refutation technique is to deny the evidence exists, or if it can’t be denied, to stick his fingers in his ears and say “la la la, can’t hear you”. Effective at playgroup level perhaps, but odd behaviour by an associate professor at the University of Auckland.

After a ritual swipe at the IPCC, he then makes the following astonishing assertion (fit the third):

It is a conveniently forgotten fact that most of the industrialised world went into hysterics during the 40 years of global cooling beginning in the late 1930s.

This is — not to put too fine a point on it — complete invention. There were a few magazine and newspaper articles about possible cooling, and at least one book, but no-one was having hysterics. Undaunted, de Freitas continues with his fictionalisation of climate history:

Fifty years ago it became clear that global carbon dioxide concentrations in the atmosphere were increasing at a rate of about 1.8 ppmv per year. It was assumed that this was the prime contributor to an observed increase in global temperatures. On this basis, the carbon dioxide data were used in climate model projections for future global warming.

Assumed? What about the fact — understood for 150 years — that CO2 has an impact on radiation passing through the atmosphere? No assumptions required. There was sound theory supported by measurement, and to have left that out of the models would have been academic suicide.

de Freitas then trots through a few crank tropes, including the mandatory assertion of global cooling:

By 2006, despite the ongoing rise in global carbon dioxide emissions, data showed that mean global temperature rise had slowed, and currently shows signs of falling.

Now that’s he’s working up a bit of steam, he delivers this final fit:

Government decision-makers should have heard by now that the basis for the longstanding claim that carbon dioxide is a major driver of global climate is being questioned; along with it the hitherto assumed need for costly measures to restrict carbon dioxide emissions. If they have not heard, it is because of the din of global warming hysteria that relies on the logical fallacy of ‘argument from ignorance’ and predictions of computer models.

Risible. The only person arguing from ignorance is de Freitas. The “din of global warming hysteria” comes not from the real science that underpins our understanding of the problem, but from sceptics like de Freitas who have to make ever more shrill and ridiculous pronouncements to be heard.

On the other side of the Tasman, Bob Carter is the better writer, but equally ridiculous in his arguments:

…the real climatic risks faced by our societies, not least because it assumes that global warming is more dangerous, or more to be feared, than is global cooling. In reality, the converse is true.

That’s the version of reality that Bob and his crank mates occupy. It’s a strange planet, but not ours. They have odd models too…

Some computer models (General Circulation Models; deterministic) project that the global temperature in ten years time will be warmer than today’s. Other computer models (statistical; based upon projection of past climate patterns) project that global temperature will be cooler ten years hence. The reality is, therefore, that no scientist can tell you with confidence whether the temperature in 2020, let alone 2100, will be warmer or cooler than today’s.

Told you Bob’s planet was a strange place. On the one I inhabit there are plenty of people, scientists even, who would happily accept a wager that the next ten years will be warmer on average than the last ten. And I know of no credible “statistical models” that project cooling — but I do know of at least one that projects continued warming.

Bob then delivers a broadside against Australia’s planned emissions legislation, and finishes with this dramatic flourish:

If such a monstrously socially damaging and environmentally ineffectual measure as the government’s carbon dioxide taxation bill becomes law, it will stand for decades as an indictment of all the parliamentarians who voted for it.

In which event, be sure to remember their names, for nothing is more certain than that you are going to want to exercise retribution thereafter.

The names that will be remembered as the world burns will be those of the vocal minority who were willing to prostitute their academic reputations in service of delaying action. One wonders what “retribution” Carter and de Freitas will face. Opprobrium and ridicule will be the least of their worries when harsh reality intrudes on their ideology.