Key degrees of difference
Cameron Stewart, Associate editor | August 09, 2008
http://www.theaustralian.news.com.au/story/0,25197,24148862-11949,00.html
HAS global warming stopped? The question alone is enough to provoke scorn from the mainstream scientific community and from the Government, which says the earth has never been hotter. But tell that to a new army of sceptics who have mushroomed on internet blog sites and elsewhere in recent months to challenge some of the most basic assumptions and claims of climate change science.
Their claims are provocative and contentious but they are also attracting attention, so much sothat mainstream scientists are being forced torespond.
The bloggers and others make several key claims. They say the way of measuring the world’s temperature is frighteningly imprecise and open to manipulation. They argue that far from becoming hotter, the world’s temperatures have cooled in the past decade, contrary to the overwhelming impression conveyed by scientists and politicians.
As such, they say there should be far greater scepticism towards the apocalyptic predictions about climate change. Even widely accepted claims, such as that made by Climate Change Minister Penny Wong that “the 12 hottest years in history have all been in the last 13 years”, are being openly challenged.
“She is just plain wrong,” says Jennifer Marohasy, a biologist and senior fellow of the Institute of Public Affairs. “It’s not a question of debate. What about the medieval warming period? The historical record shows they were growing wine in England, for goodness sake; come on. It is not disputed by anyone that the Vikings arrived in Greenland in AD900 and it was warmer than Greenland is now. What Penny Wong is doing is being selective and saying that is a long time ago.”
But selective use of facts and data is fast becoming an art form on both sides of the climate change debate now that real money is at stake as the West ponders concrete schemes to reduce carbon emissions. So what is the validity of some of the key claims being made by these new blogger sceptics?
Their first claim is that the most basic aspect of climate change science – the measurement of global warming – is flawed, imprecise and open to manipulation.
The earth’s temperature is measured using land-based weather stations – in effect, a network of thermometers scattered unevenly across the globe – as well as via satellites and ocean-based weather sensors. There are four agencies that measure the world’s temperatures and each has different methodology and produces varying, although not dramatically different, results.
Sceptics accuse climate change believers of always quoting the agency that shows the highest level of warming, the US National Aeronautic and Space Administration’s Goddard Institute for Space Studies run by prominent climate change scientist and activist James Hansen.
An independent study by Yale University in the US shows GISS says the earth has warmed by 0.025C a year during the past eight years while the other best-known measurement agency, London’s Hadley Centre, says it warmed by only 0.014C a year during the same period. Not surprisingly, the Hadley figures are the most quoted by climate change sceptics while the GISS figures are most popular with climate change believers.
David Evans, former consultant to the Australian Greenhouse Office, says Hansen’s GISS is unreliable because it is the only measurement agency that relies almost wholly on land-based data instead of satellites.
“Land-based temperature readings are corrupted by the urban heat island effect,” he says. “Urban areas encroaching on thermometer stations warm the micro-climate around the thermometer due to vegetation changes, concrete, cars and houses.”
As such, he alleges that the GISS figures – which are enormously influential in the climate change debate – are “hopelessly corrupted” and may even be manipulated to suit Hansen’s views on global warming.
A group of weather buffs in the US also has attacked GISS’s methodology, putting together an online photo gallery of US weather stations at website www.surfacestations.org that shows some thermometers situated next to asphalt runways and parking lots where they would pick up excess warming.
But GISS says the distorting impact of this urban warming is negated because data from these stations is modified to remove these effects and give a true reading. Hansen acknowledges there may be flaws in the weather station data because temperature measurement is not always a precise science. But he says this does not mean big-picture trends can’t be drawn from the data.
He says: “That doesn’t mean you give up on the science and that you can’t draw valid conclusions about the nature of earth’s temperature change.”
Hansen has been infuriated by the attacks on GISS by climate change critics. Last year Canadian blogger and retired businessman Stephen McIntyre exposed a minor mistake in Hansen’s figures that had caused GISS to overstate US temperatures by a statistically small 0.15C since 2000.
Sceptics were energised. “We have proof of man-made global warming,” roared conservative American radio host Rush Limbaugh. “The man-made global warming is inside NASA.”
Hansen struck back, saying he would “not joust with court jesters” who sought to “create a brouhaha and muddy the waters in the climate change story”.
What the bloggers have succeeded in doing is to highlight that measuring climate change is an evolving science. But their success has been at the margins only. So far they have failed to prove that these discrepancies negate the broader core arguments about the trends of global warming.
However, the second argument being put forward by blogger sceptics is more accessible to the public and therefore is having a greater impact. They argue that, contrary to the impressions given about global warming, the earth’s temperatures have plateaued during the past decade and may have cooled in recent years. This, they argue, should not be happening when carbon emissions are growing rapidly. This was not what the climate change modellers predicted. Their conclusion therefore is that carbon emissions are not the driver of warming and climate change and that the earth is not heading for a climate change apocalypse caused by greenhouse gases.
“All official measures of global temperature show that it peaked in 1998 and has been declining since at least 2002,” says climate change sceptic Bob Carter, a science adviser to the Australian Climate Science Coalition. “And this is in the face of an almost 5 per cent increase in atmospheric carbon dioxide since 1998. Spot the problem?”
A careful analysis of global temperature graphs from each of the measurement agencies confirm that – despite variations between them – there has not been any notable warming since 2000. Depending on which graphs you use, global temperatures since 2000 have been more or less flat. Some, such as the GISS data, show a modest rise, while others show negligible movement and even a small fall in recent years.
Sceptics like to use graphs that date from 1998 because that was the hottest year on record due to El Nino influences and therefore the temperature trends for the decade look flattest when 1998 is the starting point.
But ultimately this is a phony war because most mainstream scientists do not dispute that global temperatures have remained relatively flat during the past decade. Where they differ with the sceptics is on how this outcome should be interpreted.
“The changes in temperature over the past 10 years have basically plateaued,” says Andy Pitman, co-director of the Climate Change Research Centre at the University of NSW. “But scientists did not anticipate a gradual year-by-year warming in temperature. What matters is the long-term trend. This outcome does not change any of the science but it does change the spin climate deniers can put on it.”
The sceptics are having a field day with this trend. The IPA’s Marohasy says: “In the last 10 years we have seen an increase in carbon dioxide levels yet temperatures are coming down. That, if anyone looks at the actual data, is not disputable. Carbon dioxide is not driving temperatures because there are other important climatic factors at play.”
Most scientists are adamant that any assessment of climate change based on only 10 years of data is not only meaningless but reckless.
“From a climate standpoint it is far too short a period to have any significance,” says Amanda Lynch, a climate change scientist at Melbourne’s Monash University. “What we are seeing now is consistent with our understanding of variability between decades. If we hung about for another 30 years and it kept going down, then you might start to think there is something we don’t understand. But the evidence at this point suggests this is not something we should hang around and wait for.”
Climate change scientists say we must go back much further than the past decade and pay attention to the longer-term trend lines that run through the temperature data and clearly trend upwards. Lynch says other factors beyond temperature are also relevant. “In the last 10 years there has been a catastrophic and massive Arctic sea ice retreat. We’ve seen glacial retreat, permafrost thaw and ocean thermal expansion, so temperature is not the whole story.”
But the sceptics are undeterred. “It is widely alleged that the science of global warming is settled,” says the US-based Science and Public Policy Institute. “This implies that all the major scientific aspects of climate change are well understood and uncontroversial. The allegation is profoundly untrue … even the most widely held opinions should never be regarded as an ultimate truth.”
Matthew England, from the Climate Change Research Centre, describes the latest blog war by climate change sceptics as an amazing phenomenon. “Climate change is a robust area of science and there is plenty that is still being debated and new discoveries are still being made,” he says. “It is a topic (that) will keep attracting different opinions from enthusiasts and from bloggers. They are a minority but they are proving to be a very vocal group.”
If the greenhouse effect has become so much greater, why hasn’t the huge amount of heat released in the ’98 El Nino been better retained in the atmosphere?
Just wondering,
Mike
Ok, picking up on a few comments/questions in my direction (and, incidentally, I’m sorry if people feel I’m posting too much, but I do think it is courteous to respond and, whilst I think it will already be evident that I’m not close to the consensus view on this board I hope that people are interested in different points of view. So, I’ll continue to respond if it seems interesting, or else I’m happy to b off if it seems dull ;-)) –
Pofarmer –
My view is that whilst palaeo research is very helpful in understanding how the climate has responded in the past, we do not ‘need it’ in order to assess potential greenhouse gas effects. I am not aware of any climate scientist – not Lindzen, not Spencer, not Christy – that rejects the warming influence of C02. The debate is over how much that influence may be, over climate sensitivity and the balance of feedbacks. I’m fascinated by palaeo stuff, but it doesn’t resolve the question of whether we do or do not understand the physics of what’s going on in the climate now. If, for example, the global climate was equivalently warm during the MWP, then we still need to explain that in terms of natural forcings. We’re not best placed to observe the conditions of the 11th century, say, so that’s a tough challenge for then! We’re better placed looking at now, and we need as much science as possible bearing upon that. I think that the palaeo record neither proves nor disproves AGW, and, honestly, I’m not aware of anyone of consequence disputing the basic physics of AGW, only the extent of its effect in a complex system.
Bruce Cobb –
In other words, Steven, you believe AGW is true. The question is, on what basis?
Because the IPCC said so, and there is an “overwhelming consensus?”
No, on the basis of fundamental physics, which is the same basis upon which Richard Lindzen or Roy Spencer believe it is “true” (your word). Like them, I am uncertain of the extent of its effect, unlike them, I am inclined to think it may be significantly above say +1C for a doubling of C02. The difference of opinion is not one concerning the basic physics of GHGs but concerning the matter of climate sensitivity.
Tom Klein –
I have a difficulty understanding the difference between a ” transient ” and “equilibrium” response of the climate. Since the IPCC predicts monotonically changing forcings, the difference between the two – if such thing exist at all – must be one of time delay.
Yes, that’s right. The transient figures I quoted are projections for at the time of C02 doubling, the equilibrium figures are for long-term temperature projections if the C02 level were to remain constant from that point. Simplifying, it’s a matter of 1) the latency of heat distribution (the oceans take a long time to warm) and 2) the working through of feedbacks (so, increased humidity would be a short-term feedback but albedo changes would be longer-term – it takes a while to melt ice-packs). It’s thought (IPCC) that there’s already a further +0.5C ‘in the system’ even if we were to stabilise C02 concentrations now. You’re absolutely right that El Nino/La Nina events will throw up rapid temperature responses, especially in the assessments of lower troposphere temperatures (which, incidentally, is why the satellite records show such sensitivity to these events and to the influence of volcanic eruptions), but these are ocean circulation events rather than immediate responses to whole-ocean warming (whether these circulation events are changing in response to warming remains a moot point). I’m not sure if that responds well enough to your point, but I don’t want to go on too long!
Dave Andrews –
If you read through the threads at Climate Audit you will indeed see some bizarre behaviour by a good few of the Team
I do read Climate Audit. All I will say for now is that Steve McIntyre presents his point of view on his blog. I read the scientific literature, and I look forward to his next publication, which I believe he has in the pipeline.
Janama –
Do you think it’s possible to compose a computer program dealing with all the complexities of climate, including temperature, whilst having no knowledge of any of the complex variables the model seeks to represent? That’s what you are inferring and what I found to be insulting toward Dr Evans.
I’m at a loss, really. I’m sorry if you think it’s insulting for me to point out that’s he’s made a false statement regarding the derivation of the GISS data in comparison to other records. I’ve suggested why he might have made such a mistake, but if you think that implies insult, then I don’t know what to say further. If, as you suggest, he must have good knowledge of these matters, then I must ask you why you think he should knowingly state such a falsehood? (And yes, by the way, I think it’s entirely possible to create such a computer programme without needing to know how GISS or Hadley or anyone else produce their temperature data).
“Evidently, you think that these scientists are are driven by a bizarre agenda which determines that they must ruin the world economy on the back of fabricated science”
Steven Talbot,
I have to agree with Dave Andrews. I’ve lurked around Climate Audit for about 3 years, and I can tell you when that the Team rarely can answer to the statistical criticisms that professional statisticians throws at them. MBH9X and most dendro studies are in fact statistical analysis and not studies concerning phyiscal theories. As a matter of fact, most climate analysis is heavily reliant on advanced statisical analysis. Yet, as Wegman has observed, most climate scientists have a poor understanding of statistical theory and practice. Mann himself, was chastised for his use of Principle Components Analysis.
Having walked among the halls of published scientists, this high regard for scientific integrity is unwarranted. They hold their tongue on the merits of proposals because they review each OTHER’S proposals. What gets through the initial gate prior to funding is a back scratching endeavor that is closed to anyone not willing to play the game. And they steal each other’s stuff like common thieves. Would you believe that Watson was not the lead investigator regarding the structure of DNA? It was a woman research assistant in another office and they managed to steal her photos and writings.
So please, let’s not put scientists on marble pedestals. They are prone to bias, and willing to continue their research in that biased stream till the money runs out, just like we are. They are also susceptible to unscrupulous endeavors, just like we are.
For old construction worker’s reference that didn’t work for me, I googled
“Statement of Dr. David Deming” and the first hit was it.
Thanks.
Glen
sorry about address
http://epw.senate.gov/hearing_statements.cfm?id=266543
Steven Talbot (18:29:17)
I have a question for you
Considering that the oceans and land temperatures have been flat for the last 8 years what has been the amplification number for climate sensitivity ?
“…The central value of 3 °C is the amplification by a factor of 2.5 over the direct effect of 1.2 °C (2.2 °F). Well-documented climate changes during the history of Earth, especially the changes between the last major ice age (20,000 years ago) and the current warm period, imply that the climate sensitivity is near the 3 °C value. However, the true climate sensitivity remains uncertain, in part because it is difficult to model the effect of feedback. In particular, the magnitude and even the sign of the feedback can differ according to the composition, thickness, and altitude of the clouds, and some studies have suggested a lesser climate sensitivity.”
Climate Change Science: An Analysis of Some Key Questions, pp 6-7,
Committee on the Science of Climate Change
National Research Council
Steven Talbot, you missed my point. In the Doomsday book wine production is a substantial economic activity.
From the Doomsday book,
Hundred of Rochford. Suen holds Rayleigh in demesne as one manor and 5 hides. Now 1 park, and 6 arpents of vineyard, which produce 20 muids of wine if it does well.
An arpent is 3400 SqM or a bit less than an acre. A muid appears to be a wagon load. So one location was producing 20 wagon loads of wine from 5 acres of vineyards.
There are no later references to this scale of wine production. Counting vineyards is misleading as nobles and monks would have grown grapes for their own consumption in small protected positions. By way of comparison oranges have been grown in England since the 1600s. There were hundreds orangeries in the 18th century. However, oranges have never been a commercial crop in Britain.
Steven Talbot,
Falsehood? You really need to look at the article again. It reads:
=====
David Evans, former consultant to the Australian Greenhouse Office, says Hansen’s GISS is unreliable because it is the only measurement agency that relies almost wholly on land-based data instead of satellites.
“Land-based temperature readings are corrupted by the urban heat island effect,” he says. “Urban areas encroaching on thermometer stations warm the micro-climate around the thermometer due to vegetation changes, concrete, cars and houses.”
As such, he alleges that the GISS figures – which are enormously influential in the climate change debate – are “hopelessly corrupted” and may even be manipulated to suit Hansen’s views on global warming.
=====
Notice that the first paragraph has no quotation marks? That’s because they were the writer’s words, not Evans. Know how I know? Because the next two paragraphs have quotation marks. Those probably are Evans words. I say ‘probably’ because I wasn’t there to hear the interview myself.
Also, you might want to think about the meaning of ‘almost’ in the writer’s sentence. Even in the writer’s paraphrasing of Evans’ words, the word ‘almost’ means Evans did not say something as absolute as you state.
Lastly, were you in the room at the time of the interview? Do you know for a fact that Evans did not make a very cogent explanation about the myriad of GISS adjustments and it just went over the writer’s head? If not, please do us all a favor and let it go. There is no need to accuse someone of ‘falsehoods’ over a non-quote. It is just as likely that the writer lost some meaning when he did his best to encapsulate something complicated into a single sentence — and he did so knowing that it was just one aspect of his article. No harm. No foul.
Don’t fret about answering me. I will not think you impolite.
Steve Talbot – I don’t think you’re posting too much, as you seem to think.
I for one have enjoyed reading your thoughtful and polite comments. Pity there’s not more posters in the AGW blogosphere like you, who can defend a more AGW point of view as reasonably as you are doing.
So, keep it up Steven, and what ever you do don’t stop posting here at Anthony’s blog After all, it can get just a bit dull reading post after post from people who agree with your own point of view. Challenge us sceptics! Give us all something to think about (and to discuss)!
No, on the basis of fundamental physics, which is the same basis upon which Richard Lindzen or Roy Spencer believe it is “true” (your word). Like them, I am uncertain of the extent of its effect, unlike them, I am inclined to think it may be significantly above say +1C for a doubling of C02. The difference of opinion is not one concerning the basic physics of GHGs but concerning the matter of climate sensitivity.
Steven, I would like to know which “fundamental physics” book you are reading from which proves that 1) C02 can drive temperatures (yes, we all know there is a greenhouse effect), and 2) that man’s paltry 3% or so contribution of C02 can contribute anything more than noise to our climate.
You do know that 3 of 4 major Ice Age periods existed during periods with much higher atmospheric CO2 levels than now, right?
There are plenty of vineyards (over 400 in England since 1980) now producing rather nice wines, I enjoy a few glasses of wine from the Plumpton Estate with Jean and Roger the handyman.
Very civilised!
jc stout,
Here is a link to a previous article (July 18th 2008) in ‘The Australian’ written by Dr David Evans himself, so no possibility in this of poor reporting:
“NASA reports only land-based data, and reports a modest warming trend and recent cooling. The other three global temperature records use a mix of satellite and land measurements, or satellite only, and they all show no warming since 2001 and a recent cooling.”
http://www.theaustralian.news.com.au/story/0,25197,24036736-7583,00.html
Frankly, his statements there are even more obviously wrong! 1) NASA does not report “only land-based measurements” and does use satellites and 2) Hadley (which I presume he’s including in “the other three”) does not use satellites. I won’t speculate any further on why he is making such badly wrong statements, but I hope you can see from this that it’s not a matter of the reporter misrepresenting him.
I won’t return to this point again here. People can read the above link and make up their own minds based on Dr Evans’ own words.
Steven Talbot (14:20:57) : “GISS uses only satellite measurements.”
Your statement is most assuredly false. Anyone with a rudimentary understanding of GISS knows of its reliance on land-based temperatures. (And anyone who wants to dance with insanity can try to figure out the lights-on / lights off and adjustment methodology used by GISS.)
I (and you) do not know the exact words or the context of the statement by David Evans or to what degree the reporter inserted his own interpretation. However, we do have your exact quote — which is just plain wrong.
Now, you could argue (and perhaps persuasively) that your statement is being misunderstood; after all, it is only one sentence out of a larger paragraph. Exactly. Unless, you can point to an article written by David
Evans in which he advances the error you perceive, I would suggest focusing on his message being discussed by the reporter. I understand that message to be that the land-based measurements are prone to overstating temperature trends as opposed to satellite measurements.
Take a peak at Joe d’Aleo’s graph of station closures and global temperatures with sharp discontinuities of both in 1990 at his article at Climate Science.
==============================================
Opportunity cost
An asteroid came at us
but what could we do?
We’d spent all
our money
to reduce CO2.
old construction worker,
Considering that the oceans and land temperatures have been flat for the last 8 years what has been the amplification number for climate sensitivity ?
Hmm. I don’t know how to answer that. I agree with the NRC quotation that you follow up with. I don’t think the science is at the stage of being able to assess short term changes in sensitivity in response to ENSO phases, for example. The assessment of feedback for a doubling of C02 is a long-term matter, of course.
Philip_B,
Yes, that’s a fair point, that the number of vineyards is not sufficient information. I can’t find reference to any idea of production figures over the centuries, so maybe a visit to the library is called for! I’m sceptical of there being a close correlation between temperature and production though, in that the commercial production of wine will have been affected by other social factors, including trade access to European wines, the effects of the Black Death, and so on. You’ll note that I think there was an MWP, so I am not doubting that conditions were relatively favourable for viticulture at the time, only doubting that we can presume an absolute temperature from that.
Bruce Cobb,
Steven, I would like to know which “fundamental physics” book you are reading from which proves that 1) C02 can drive temperatures (yes, we all know there is a greenhouse effect)
I’m not sure that I understand your question. If there is a greenhouse effect, to which C02 contributes, then its concentration will affect the energy balance. May I quote Richard Lindzen (whom I hope you’d accept as being a forceful sceptic) in respect of this? –
There has been a net warming of the earth over the last century and a half, and our greenhouse gas emissions are contributing at some level. Both of these statements are almost certainly true. What of it?
http://www.newsweek.com/id/35543
2) that man’s paltry 3% or so contribution of C02 can contribute anything more than noise to our climate.
I take it you mean a 3% contribution to the greenhouse effect rather than to the concentration of C02? Well, my answer is that a 3% contribution to the performance of my investments will make a huge impact on my wealth over a long period. Perhaps I’ve misunderstood you?
You do know that 3 of 4 major Ice Age periods existed during periods with much higher atmospheric CO2 levels than now, right?
C02 is not a heater. I used to have a lot of insulation in my roof, but my house was cold because I turned the heating down.
Paulus,
Thanks 🙂 At the moment I’m quite enjoying ‘serving myself up for dinner’, so to speak, though I may soon get exhausted! My first intent was to clarify a factual error – whatever our views, I think we should have a common purpose in getting the facts right on both ‘sides’ – but people seem keen to debate other questions, so there we are.
The MRF shows a fall signal again today with lots of cold air building up in the Arctic and two very strong upper level lows.
An Inquirer,
Steven Talbot (14:20:57) : “GISS uses only satellite measurements.”
Your statement is most assuredly false.
I wrote:
“Hadley uses only ship-based measurements for SSTs. GISS uses only satellite measurements.”
I trust that you now understand my statement in its context. It is true that GISS uses only satellite measurements for sea surface temperatures.
Unless, you can point to an article written by David Evans in which he advances the error you perceive, I would suggest focusing on his message being discussed by the reporter.
I just did – please see my post above timed at 6:27:24.
Steven Talbot,
Apologies for spelling your name wrong in my earlier post.
I agree we all want to get the facts right.
In my experience, over the last 12 months, posters here and at Climate Audit are open to discussion and rarely, nay, never dismiss people of the opposite point of view with anything approaching the level of vitriol that is regularly displayed at RC and Open Mind.
So what does that say about the willingness to debate transparently evident in the climate science ciommunity?
Steven Talbot,
Apologies for spelling your name wrong in my earlier post.
I agree we all want to get the facts right.
In my experience, over the last 12 months, posters here and at Climate Audit are open to discussion and rarely, nay, never dismiss people of the opposite point of view with anything approaching the level of vitriol that is regularly displayed at RC and Open Mind.
So what does that say about the willingness of the climate science community to debate transparently?
In other words, that 0.025C per year rise in temperatures is negated by the error. That 0.15C error is not insignificant when you’re talking about 0.20C increases!
Steven Talbot-
I don’t care what their agenda is. I’m concerned with the results of their actions. The “hockey stick” was the virtual poster child for the IPCC AR3 for the simple reason that it gets Joe Sixpack and Sharon Chardonnay’s attention. They don’t know that they exhale CO2 with every breath, and you mention feedback and they start talking about the Def Leppard concert they went to, but they can recognize the “danger” in a graph that looks like a badass ride at Six Flags.
By the way, I second those commenters who welcome your presence and your mannerly ways here.
So, you are arguing that the atmosphere warms the oceans? You do realize the oceans are about 250 times the mass of the atmosphere right? That’s like a 10,000 lb pickup truck pulling a 2.5million lb train. Not to mention that the Argo bouys don’t show the supposed deep ocean heating. It seems to me that some may well have the relationship backwards. Can the atmosphere really drive the temperature of the oceans?
Dave Andrews –
Hi Dave,
In my experience, over the last 12 months, posters here and at Climate Audit are open to discussion and rarely, nay, never dismiss people of the opposite point of view with anything approaching the level of vitriol that is regularly displayed at RC and Open Mind.
So what does that say about the willingness of the climate science community to debate transparently?
I don’t think I can usefully make any judgment on that – I’m not really a student of comparative levels of vitriol! I think that, on both sides of this, there are intense levels of conviction, and obvious difficulties in taking on board elements (facts/evidence/interpretations) that are dissonant. That is human nature, I guess. I do have ‘faith’ that in the longer term, at least, the scientific process will tend closer to whatever ‘truth’ there is to be found. I think that scientists look to the academic literature (or to conferences) as their field for open debate. Are they as open as they might be? Probably not in every case, but I don’t jump to the conclusion that they are therefore engaged in deceit.
jh,
In other words, that 0.025C per year rise in temperatures is negated by the error. That 0.15C error is not insignificant when you’re talking about 0.20C increases!
I think that you’re conflating the US temperature anomaly with the global anomaly. The effect of the 2007 corrections on the global record was in the order of 0.001 degree –
http://data.giss.nasa.gov/gistemp/updates/200708.html
Dave,
The “hockey stick” was the virtual poster child for the IPCC AR3…
I would actually accept that criticism of the AR3’s presentation, in that its visual impact put too much emphasis on what is only one aspect of the science. It had its impact, but seemingly created the impression that the accuracy of palaeo reconstructions was somehow a kingpin in the ‘theory’. I don’t think that’s so.
I actually think the ‘sceptical community’ is somewhat obsessed with hockey stick debating, whether that be in respect of the original MBH98/99 studies or hockey-stick-like reconstructions since which have used different statistical methodologies. We then get onto all the ‘Team’ stuff, etc. Personally, I would be very happy to see a robust palaeo reconstruction showing a global MWP equivalent to today’s temperatures (I don’t think Loehle meets the ‘robust’ description, but bring on a better one!). I would then want to see a scientific understanding of that anomaly developed, just as we need a scientific understanding of today’s. It is not, to my mind, a logical presumption that any past temperature variation accounts in itself for present variation.
profarmer,
So, you are arguing that the atmosphere warms the oceans? You do realize the oceans are about 250 times the mass of the atmosphere right? That’s like a 10,000 lb pickup truck pulling a 2.5million lb train. Not to mention that the Argo bouys don’t show the supposed deep ocean heating. It seems to me that some may well have the relationship backwards. Can the atmosphere really drive the temperature of the oceans?
No, direct insolation (the mass of that is even less, of course!) primarily warms the oceans , the atmosphere affects radiation loss. To oversimplify, the sun insolates and the atmosphere insulates. If we removed the atmosphere the planet would become exceedingly cold, even though the heat source (the sun) remained the same. You’re right that the mass of the oceans is such that it would take a very long time for the whole body to be raised in temperature by 1 degree, say.
I’m not sure what you’re currently basing your view of Argo data on. Lyman et al. 2006 suggested cooling over the 2003-5 period, but they corrected that last year (problems with Argo float calibration) – but anyway, this referenced the upper ocean. I didn’t know that the Argo floats recorded the deep ocean…..?