This is just one of dozens of responses to common climate change denial arguments, which can all be found at How to Talk to a Climate Sceptic.
Objection:
Satellite readings, which are much more accurate, show that the earth is in fact cooling.
Some very old news here, that's all. I wonder how long before this one stops being brought up?
Answer:
There are a few advantages to the satellite readings, mainly the more uniform global coverage and the fact that readings can be taken at different altitudes. However, it is in fact a very complicated process which uses microwaves emitted by the oxygen in the atmosphere as a proxy for temperature. The complications arise from many things including decay of the satellite orbits, splicing together and calibrating records from different instruments, trying to separate the signals by the layer of atmosphere they originate from etc. It is a little ironic that generally the same people who distrust the surface record so much happily embrace this even more convoluted exercise in data processing!
Anyway, it is already many years since the satellite analysis actually showed cooling. Until recently though, one of the several analyses of tropospheric temperatures did show only very little warming and was in direct contradiction to the model predictions which say the troposphere should warm significantly in an enhanced greenhouse environment. Something had to be wrong, the observations or the model predictions. Naturally the sceptics had no doubt that it was the models that were off.
However, it turns out that some additional errors were uncovered and the MSU Satellite temperature analysis now shows warming well in line with model expectations. Real Climate has a good run down of the technical details for those with the stomach for it! In short, this long running debate turned out to be a great validation of the models and a real death blow to the "earth is not warming" crowd.
Beware of zombies!
(image from Global Warming Art)
This is just one of dozens of responses to common climate change denial arguments, which can all be found at How to Talk to a Climate Sceptic.
"Satellites Show Cooling" was first published here, where you can still find the original comment thread. This updated version is also posted on the Grist website, where additional comments can be found, though the author, Coby Beck, does not monitor or respond there.
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So what you are saying is 30 years of satellite data has now become invalid by simply tweaking a few lines of code to remove an error in the data processing and hey presto the sat data now matches with the model predictions.
What i would like to see is a graph which compares the pre tweaked sat data, the model prediction data and the weather balloon data. To tweak sat data is one thing but to dispute the accuracy of a thermometer is another.
Posted by: Crakar14 | December 9, 2008 3:38 PM
Sorry to burst your conspiracy theory bubble, Crakar, but those satellite studies you think are being falsified are produced by Spencer and Christy, two darlings of the denialist campaign.
Check out all of the various temperature indicators here
Posted by: coby | December 9, 2008 5:24 PM
Conspiracy theory bubble?
From your link"Based on data from Angell's global network of 63 radiosonde stations, over the period from 1958 through 2005, the global mean, near-surface air temperature warmed by approximately 0.17°C/decade, the 850-300 mb tropospheric layer warmed by about 0.09°C/decade, the 300-100 mb tropopause layer temperature cooled by approximately -0.23°C/decade (driven mainly by large changes in the Polar zones), and the 100-50 mb low-stratospheric layer cooled by about -0.62°C/decade. At the surface, 2002 remained the warmest year in the 48-year record (0.88°C above the long-term mean), and 2005 was the second warmest year with a departure of 0.82°C"
Dont see too much warming here do you?
Posted by: Crakar14 | December 10, 2008 9:25 PM
Cooling above the troposphere is a predictable response to an enhanced greenhouse caused warming and this observation is more evidence against the other candidate causes out there, such as GCR or increased insolation.
Now, why are you switching to radiosondes? I guess you have no response regarding Spencer and Christy's satellite analysis...
Posted by: coby | December 11, 2008 5:52 PM
First of all if you are going to supply links to supporting evidence the evidence should be up to date not 3 years old. That aside i have switched to radiosondes as the debate has progressed. As you state the troposhpere should warm as per model predictions.However the sat data showed no warming so something was wrong.
What i find funny about all of this is rather than doubt an as yet (due to sat data) unproven theory they went straight to the sat data and went searching for an error that may not have even existed. But low and behold they find one and after a tweak here and a tweak there hey presto the sat data now matches the theory.
Of course there is the problem of that pesky radiosonde data that still shows no warming, oh i no we can just re jig the data on that as well.
So in the end we had two independent sources of data that were considered accurate and therefore valid, until they both diverged (both showed cooling or no warming)
from an unproven theory. Rather than treat these two independent sources of data as being accurate they simply tweaked the data to suit the theory. This is not science Coby.
Posted by: Crakar14 | December 11, 2008 8:29 PM
Being that we live exclusively in the troposphere, that's the layer I'm most concerned with.
Posted by: Mrs. W | January 3, 2009 11:15 AM
Am I wrong or does the linear regression of the data start a couple of years after the satellite data? If you started the regression at 1979 (particularly for the UAH data), it looks to me like the slope of the line would be almost flat (perhaps a slight increase). If you include the early data and update the data to 2008, what does it look like?
Posted by: Mark | February 15, 2009 9:26 PM
I've just plotted all the UAH data, including June 2009. Sorry, there's no warming in the past few years. Certainly the last 7 years is cooling. Without doing the stats, it looks like about 0.2 degC warming over the past 30 years, and decreasing.
Posted by: R James | July 10, 2009 5:33 AM
R James,
The issue we are concerned about is change in climate. Climate is defined as roughly 30 yrs average weather. You can not make any conclusions about climate trends with anything less than 15 or 20 years, so observations over the last 7 or 10 or 11 are not enough.
Please see this post:
http://scienceblogs.com/illconsidered/2008/09/signal_vs_noise.php
Posted by: coby | July 10, 2009 8:41 AM
Posted by: dhogaza | July 10, 2009 9:29 AM
I agree, it's accepted that climate trends need at least 30 years of data to be meaningful. How about 4,000 years. http://www.greenworldtrust.org.uk/Science/Images/Main/Warm_periods.jpg OOps - long term trend looks like cooling, and looks like the rise of the past 100 years is nothing unusual.
I see that you don't like satellite data, but I have a few concerns about surface data when I see that the magnitude of adjustments is about the same as the anomaly. http://www.strangerthanfiction.org/2009/07/10/rss-global-temperature-for-june-09-also-down/
Posted by: R James | July 10, 2009 5:23 PM
I can make shit up too. Making shit up doesn't prove science to be wrong.
Oh, gosh, someone who doesn't think that the raw satellite data needs to be adjusted, too ...Regardless, your comment's just another restatement of statistical illiteracy
Posted by: dhogaza | July 10, 2009 5:56 PM
R James,
If you knew it takes 30+ years to talk about climate, why did you talk about 7?
Thanks for one of the clearest examples of arguing out of both sides of your mouth. In one breath you switch from preferring a 7 year temperature record over a 150 year record to preferring a 4000 year record over a 150 year record. Any argument, as long as it supports you preferred conclusion.
Posted by: coby | July 10, 2009 8:10 PM
Strange, I don't recall saying that satellite data doesn't need correction. I simply pointed out that surface temperature also requires correction. Actually, I find that there's surprisingly good agreement between the two methods (although GISS struggles a bit to match the others).
I can find lots of sources of longer term data, if the one I presented earlier doesn't suit you. They all have one thing in common - there's nothing unusual about current climate movement.
Posted by: R James | July 10, 2009 11:31 PM
And don't give me that lying denialist crap about the hockey stick being debunked by a retired business man from the mining industry or a tv weather broadcaster who apparently never even got an undergraduate degree.
Posted by: dhogaza | July 11, 2009 9:50 AM
Dhogaza -
Some of us would be interested in knowing exactly what aspects of Steve McIntyre's deconstruction of the hockey stick you disagree with.
I am sure you won't simply take refuge in calling him a liar, a denier and fraud, but will be more specific in your objections. I am sure, too, that you won't merely say that lots of people have carried out their own analyses and agree with the hockey stick - bearing in mind that it is part of Mr McIntyre's case that these apparent validations repeat the original errors.
Or course, you may think that he is wrong in making this claim. Even so, I am sure you will agree that you cannot justify a statistical procedure by pointing to other studies which are accused of making the same invalid assumptions. No, you must show where, precisely, the problem lies.
Looking forward to reading your analysis.
Posted by: Snowman | July 11, 2009 5:47 PM
I first ran across McIntyre when he was claiming that the NAS review of the original Mann hockey stick supported the "hockey stick debunkers", when it's clear that the report says the opposite. That makes McIntyre a liar.
The denier bit is obvious.
Posted by: dhogaza | July 11, 2009 6:30 PM
If he's right, of course, then there really *is* a global conspiracy among climate scientists and climate science is a fraud. You may go on believing it if you wish.
Posted by: dhogaza | July 11, 2009 6:38 PM
It's interesting that the IPCC discretely dropped the hockey stick from its 2007 report. Anyone glancing at it can see that it missed the little ice age etc. It just didn't fit in with existing known trends.
Posted by: R James | July 11, 2009 8:10 PM
Considering MBH98 is over 10 years old and there has been a great deal of new research in that area it is hardly surprising that it is no longer prominently featured. It is however still referenced and presented together with a multitude of other reconstructions (see Chapter 6 of AR4 (large PDF): http://ipcc-wg1.ucar.edu/wg1/Report/AR4WG1_Print_Ch06.pdf ).
That would be fig 6.10 and it still looks like a hockey stick.
Posted by: coby | July 11, 2009 8:33 PM
Love it, leave it, loath it, within science Mann's work is now well-established.
What denialists need to do is to establish their own answer to science - which of course, McIntyre and Watts etc are trying to do.
Pity they're restricting themselves to scientific results that happen to contradict their own political beliefs.
You'd think that if they really believe BlogScience by non-scientists is superior to science done by professionals that they'd attack all of science, to make it clear that they're really only interested in Truth and Beauty, not politics.
Posted by: dhogaza | July 11, 2009 9:24 PM
Coby -
"It" (the Hockey Stick) "is however still referenced and presented". Yes it is and that is the shame of the IPCC that such a fraudulent piece of work is still there. It is the Hockey stick and the story behind it that first lead me to doubt the IPCC story on global warming. Gore's lies and further research convinced me things dont quite add up.
The Hockey Stick - temperatures remain dead steady almost for the last 1,000 years. Gone are the little Ice Ages and the Medieval Warm period. The little Ice Age the warmists say was a "local phenomenon". It coincided with the Maunder minimum. The Sun of course is a global phenomenon. And the warmists want to discount the Sun's influence. So local phenomenon? I dont think so!
The Medieval warm period - did it exist - of course! Was it warmer than today - definitely! Was it a Global phenomenon? Yes! The people with the largest database on the subject:
http://www.co2science.org/data/mwp/mwpp.php
You claim it doesnt matter whether it was or not (warmer). Oh yes it does! The warm period happened without the help of Anthropogenic CO2. It would cast complete doubt on the AGW hypothesis - which depends heavily on the warming of the last 3 decades or so.
Posted by: Richard | July 11, 2009 9:42 PM
Why fraudulent?
1. The authors of the graph had used the varying widths of tree-rings as THEIR PRINCIPAL METHOD of estimating early-climate temperatures.
2. THE IPCC HAD, prior to this, WARNED AGAINST USING TREE-RINGS AS PROXIES for pre-instrumental surface temperatures as they were prone to be inaccurate.
3. They none-the-less used them and gave them 390 TIMES AS MUCH WEIGHT AS ANY OF THE OTHER DATA THEY USED
4. Not only did the authors of the “hockey stick” use temperature proxies that the IPCC had said should not be used; not only did they give these questionable proxies 390 times more weight than other data; but they ALSO LEFT OUT THE TREE-RING DATASET THAT INCLUDED THE MEDIEVAL WARM PERIOD ITSELF!
5. Then the graph’s authors said in the scientific paper that accompanied their graph THAT THEY HAD INCLUDED THE TREE-RING DATASET FOR THE MEDIEVAL WARM PERIOD THAT THEY HAD IN FACT OMITTED!
6. The graph’s authors inserted their own “estimates” in place of the data they had left out, BUT DID NOT PUBLISH THE FACT THAT THEY HAD DONE SO.
7. Worse, THEY HID THE MISSING DATA IN A FILE ON THEIR OWN COMPUTER that they revealingly labeled “CENSORED_DATA”.
How bad can things get? - but they get worse!
Posted by: Richard | July 11, 2009 10:15 PM
Coby - As one British journalist put it, the hockey stick is 'the most discredited artefact in the history of science'.
It is disappointing that you try to justify it, and unworthy of you. You obviously have a sound grasp of the science of this topic, but it damages your credibility when you defend the indefensible. It would strengthen your case if you were to say, ok, we got it wrong, and move on to matters where reasonable people may still disagree.
Of course, this would mean conceding that the Mediaeval warm was true. But there we are. You cannot distort the facts to fit your theory. The theory must be adapted to the facts.
Posted by: Snowman | July 11, 2009 10:24 PM
8. When McIntyre and McKitrick obtained from the authors of the “hockey stick” the computer program they had used in compiling the graph, they found it PRODUCED A “HOCKEY STICK” EVEN WHEN THEY USED RANDOM DATA FROM A TELEPHONE BOOK!
9. Geophysical Research Letters finally published a paper by McIntyre & McKitrick exposing the defects in the graph (McIntyre & McKitrick, 2005).
10. “This paper provoked astonishment and dismay throughout the climatological community. That was the first moment at which many honest scientists who had previously accepted the climate scare at face value began to question the methods and the motives of the handful of politicized scientists.”
11. Three statisticians were engaged by the US House of Representatives (Wegman et al., 2005) to examine the evidence on both sides.
12. In a damning report, the statisticians confirmed all of the findings of McIntyre and McKitrick to the effect that the graph was defective.
13. The statisticians also found that a suspicious collection of subsequent papers that had suddenly appeared supporting the assertion that the medieval warm period had not existed.
14. They found that these had nearly all been written by associates or co-authors of the inventors of the defective graph, and using similarly questionable data and methods!
Posted by: Richard | July 11, 2009 11:25 PM
15. In the July 2005 hearing, Edward Wegman, a George Mason University statistician, testified on behalf of the mathematicians who reviewed the Mann papers. “The controversy of the [Mann] methods lies in that the proxies are incorrectly centered on the mean of the period 1902-1995, rather than on the whole time period.” He explained that these statistical procedures were capable of incorrectly creating a hockey stick shaped graph.
16. Gerald North, chair of the National Research Council committee, testified at the hearing that he agreed with Wegman’s statistical criticisms, but said that those considerations “did not alter the substance of Mann’s findings”! (How on Earth is that possible?) North said that large scale surface temperature reconstructions “are only one of multiple lines of evidence supporting the conclusion that climatic warming is occurring in response to human activities.” Effectively bailing out Mann.
17. However in the detailed 155 page report of the National Academy of Sciences, National Research Council Report, which was also chaired by Gerald North, said differently, though “buried in a lot of genteel and deferential prose”
18. They accepted McIntyre & McKitrick’s argument that Mann's method is biased towards producing hockey stick-shaped PCs
19. That uncertainties had been underestimated
20. That the bristlecone data, on which the famous hockey stick shape depends, should not have been used.
21. THEY ALSO EXPRESSED VERY LITTLE CONFIDENCE IN THE IPCC'S CLAIM ABOUT THE 1990S BEING THE WARMEST DECADE IN THE MILLENNIUM. “Very little confidence can be assigned to statements concerning the hemispheric mean or global mean surface temperature prior to about A.D. 900”
22. “The substantial uncertainties currently present in the quantitative assessment of large-scale surface temperature changes prior to about A.D. 1600 lower our confidence in this conclusion compared to the high level of confidence we place in the Little Ice Age cooling and 20th century warming.”
23. “Even less confidence can be placed in the original conclusions by Mann et al. (1999) that “the 1990s are likely the warmest decade, and 1998 the warmest year, in at least a millennium” because the uncertainties inherent in temperature reconstructions for individual years and decades are larger than those for longer time periods, and because not all of the available proxies record temperature information on such short timescales.”
24. However just before this they also slipped in that “..the committee finds it PLAUSIBLE that the Northern Hemisphere was warmer during the last few decades of the 20th century than during any comparable period over the preceding millennium.” This enabled Nature, who first published Mann’s work to say in a headline “Academy affirms hockey-stick graph”! and every other tabloid jumped in. Shame on you Nature!
Posted by: Richard | July 11, 2009 11:54 PM
Simply magnificent, Richard. I am genuinely looking forward to hearing the response from Coby and the others.
I really, really hope, Coby, that you won't disappoint us by quoting some source who disagrees with Richard's conclusions (the appeal to authority fallacy).
I hope, instead, that you will argue your case using, as Richard does, primary sources.
Posted by: Snowman | July 12, 2009 12:27 AM
From the scientific, rather than political viewpoint of building mountains of molehills, the question isn't whether or not Wegman is right that uncentered PCA analysis was the wrong tool. The question is DID IT MAKE A SIGNIFICANT DIFFERENCE.
Answer: no.
Mann's paper from last year used standard PCA, a shitload of new proxy data, and came up with virtually the same result.
Of course, not all statisticians agree that Wegman's criticism is valid, anyway.
I'm not going to bother shooting down Richard's point-by-point rehasing of The Hockey Stick Gospel According To McIntyre. It's pointless. It's a combination of molehills posing as mountains, lies, and misdirection.Go ahead and believe what you want to believe. In the world of science, it is accepted that recent warming is unprecedented in a least the last few hundred years, most likely at least 1,000, and very likely the last couple of thousand.
If it weren't for a few right-wingnut politicians like Inhofe scientists wouldn't even bother with McIntyre. It's like fighting creationists or HIV denialists. Pointless except when the lies negatively impact policy.
Posted by: dhogaza | July 12, 2009 6:18 AM
Wegman lost all credibility when he signed the Bali letter. The nonsense in that letter would get a failing grade in any first year statistics class.
He is just another denier shill. Anyone who believes a word he says is grasping at straws. Of course, that is what you deniers do, grab at straws and make them into strawmen. Such childish behaviour is not an accepted part of the scientific method.
You deniers can go on all you want, it wont change the science behind climate change but, unfortunately, it is having the tragic consequence of influencing policy.
This is of course exactly what the Oil Industry wanted in their API memo.
Posted by: Ian Forrester | July 12, 2009 6:59 AM
So, let's see, Richard posts a list cut-and-pasted from some denialist website, and it's "magnificent".
While if Coby posts a quote from an actual authority - a climate scientist - he'll be guilty of "the appeal to authority" fallacy.
Your small mind works in dishonest, twisted ways, snowman.
Posted by: dhogaza | July 12, 2009 9:44 AM
This is what I mean about McIntyre and others lying about the NAS report.
You've apparently fallen for it, or are simply dishonest, Richard. Which is it? Are you among the honest fooled, or the dishonest denialsphere?
Posted by: dhogaza | July 12, 2009 9:47 AM
Unlike you dhogaza I do not cut and paste I do my own research.
No one so far as I know have analysed the Hockey Stick saga as I have done above. Certainly not McIntyre and McKitrick, who are too technical for most to understand and not focussed enough on the what the message should be - which is Fraud and Cover-up.
I for example have downloaded the the National Academy of Sciences, National Research Council Report and read it. I have also read the Chairman Gerald North's seperate report and testimony, which is a shameful vindication of this fraud. In the National Research Council Report, they did their best and you can see where the Chairman's heavy handed intervention comes in.
dhogaza you have lost every "debate" you have had with me. (Actually very short arguments where I have quickly pointed out the flaws you have made).
In Open Thread you have said "Yes, Richard, and the professional statistician who runs that site, using the same data you claimed to use, shows that you're wrong."
Actually what he said was that my temperature data was "wrong". He said that his temperature at "11857 yrBP is about -48.3 deg.C". My temperature is -16.58C.
Now I know why the discrepancy is there, but can you figure it out? No I bet you cant! Thats because you cannot think critically for yourself, you have to depend and fall back on the crutch of "thousands of scientists say so". You have to depend on cut and paste and references to sites because you cannot explain things yourself.
Ok here is the explanation - the difference of 31.72 degrees is because my figures are anomalies from todays date (the year 2000). The rates of climb of temperatures which I have given 4.15C/Century, 2.66C/century, and 0.54C/century are absolutely correct and cannot be challanged and NOR HAVE THEY BEEN.
You said "Run on over there and continue the debate. This will be fun ... science illiterate vs. professional statistician who works with climate scientists (among others)."
Well alas there will be no debate. My reply to him has been removed and I have been debarred. He does not want a debate or questions. One of the pertinent questions I put to him was - You have claimed that global temperatures have changed extremely slowly in the past, not more than 0.1 deg.C per century, can you tell me how you have determined these global temperatures of the past?
The professional statistician is scared of a debate with a "science illiterate" - oh yes I know you will have some sarcy comments about this - he is not scared just cant waste his time with this drivel from an illiterate - there I have said it for you. But you can improve on the language - make it more foul.
Posted by: Richard | July 12, 2009 12:23 PM
I've read most of it too, and it mostly vindicates Mann's paper.
Not that it matters. Mann '08 is far stronger than the first paper, warming by CO2 rests on first principles not the climate records over the last 2000 years anyway, other researchers have gotten other results using other proxies, Mann '08 results in a hockey stick w/o bristlecone pine proxies as well as with, etc ad nauseum.
1. Science is not a blog debate. Nothing you or I say here changes the state of science one iota.
2. You "win" because you're a liar.
Scared? Doesn't care to have his time wasted by yet another dishonest, lying, science-illiterate science-denier.
Yes, what you said there was:
That's a false statement. If you use anomalies, you must SAY you are using anomalies.
Is this your idea of scoring a point? Presenting an anomaly as temperature, then when it's pointed out that your temp figure is wrong, saying "gotcha!"?
That makes you a liar, Richard, not news but nice to see it made so obvious and nice to see you admitting it, though apparently not with the sense of shame one would hope for.
You're right, actually, I didn't figure it out because I didn't imagine you'd lie so blatantly. I now know not to trust *anything* you post.
His main point, though, was that Greenland is not the world. The ice core data gives regional information only and can't be used to prove or disprove past worldwide climate trends. From the GISP2 site:
They don't claim that the Greenland ice core data says anything about global climate changes during those periods of time. Just the opposite, they talk about the need for data from other portions of the world to FILL IN REGIONAL DETAILS THROUGHOUT THE EARTH.
His pointing out that the temps were not correct was an aside, and he was right that your stated figures were incorrect, and he was right in his main point, that the GISP2 data doesn't tell us that the global climate changed at the same rate as did conditions at Greenland.
Posted by: dhogaza | July 12, 2009 2:49 PM
Despite all the above debate, I look at Mann's hockey stick, and as I said before, it fails to show the little ice age (Maunder period), and the Medieval warm period, and other. It's wrong. No amount of debate can change that.
Posted by: R James | July 12, 2009 3:21 PM
Posted by: dhogaza | July 12, 2009 3:30 PM
The coincidence of the little ice age with the Maunder period is too strong to ignore. I would expect it to have been global. Also, the hockey stick was too flat for too long leading up to recent times. Climate in the past hasn't reacted this way. It has significant peaks and troughs.
Posted by: R James | July 12, 2009 3:39 PM
This is typical of the science on the MWP:
So far so good ...
Hmmm ...
Not strongly synchronous. In other words, warmer for a bit over here, but not over there, then over there, but not over here, etc.
This does not a global climate signal make.
Even less synchronousity - if it happened at all.
Take away point - the available evidence does not support a global Medieval Warm Period.
Now, if the available evidence does not support a global MWP, why would you expect analysis of various proxies by Mann would result in the appearance of a global MWP?
Mann '08 uses a *lot* more proxies than his first paper. The evidence for a global MWP just isn't there in the available physical evidence.
Now, if more proxies giving greater coverage of the globe are uncovered which in the future shows strong evidence for a global MWP, then Mann's reconstruction methodology, using this FUTURE EVIDENCE WHICH DOESN'T EXIST YET, would also show a MWP.
Posted by: dhogaza | July 12, 2009 3:44 PM
"I would expect it". Nevermind the lack of physical evidence. Blog science doesn't need to effing evidence. Doesn't match your intuition means ... science must be wrong.
Feh.
Posted by: dhogaza | July 12, 2009 3:46 PM
This is known as an "argument from personal incredulity", a standard argumentation technique employed by science denialists.
What evidence do you have that your belief matches the expectations of climate scientists?
Posted by: dhogaza | July 12, 2009 4:01 PM
dhogaza -
"Yes, what you said there was:
From 11,857 BP to 11,558 BP, 299 years, the temperatures climbed from -16.58C...
That's a false statement. If you use anomalies, you must SAY you are using anomalies.
Is this your idea of scoring a point? Presenting an anomaly as temperature, then when it's pointed out that your temp figure is wrong, saying "gotcha!"?
That makes you a liar, Richard, not news but nice to see it made so obvious and nice to see you admitting it, though apparently not with the sense of shame one would hope for."
dhogaza - (I must keep myself from saying "you idiot", but thats what the above outburst makes you). Here is an explanation that I hope even idiots can understand.
I grab data from the net wherever I can find it. I didnt realise that it was anomalies rather than actual temperatures, till your "professional statistician" said that the temperature was actually -48.3 deg.C in the year 11857 yrBP against what I had -16.58C. He didnt tell me what was wrong I DEDUCED IT, something you are incapable of doing. It doesnt make my statement false - see below as I give a little maths lesson for dummies.
1. What I said - "From 11,857 BP to 11,558 BP, 299 years, the temperatures climbed from -16.58C to -4.17, 12.41C, thats a rate of 4.15C/Century."
2. I could have left out - (FROM -16.58C TO -4.17C), without affecting the correctness of the statement. That is:
From 11,857 BP to 11,558 BP, 299 years, the temperatures climbed BY 12.41C, thats a rate of 4.15C/Century.
Or if you are very fussy then
3. From 11,857 BP to 11,558 BP, 299 years, the temperatures climbed from {-16.58C + (-31.72C)} to {-4.17 + (-31.72C)}, 12.41C, thats a rate of 4.15C/Century.
Notice the two -31.72C's cancell each other out?
You are obviously quite challenged with simple arithmetic (addition and subtraction), but do even you understand now?
What was important in my statement was that over a period of 3 centuries, as the Earth climbed out of the last ice-age, the temperatures rose at the rate of 4.15C/Century. That is the truth.
Compare this with what your "professional statistician" said in his blog.
“It’s also worth noting that the deglaciation which takes us from a glacial period to an interglacial is fast — on geologic timescales — BUT SLOW AS MOLASSES COMPARED TO MODERN GLOBAL WARMING. THE TOTAL TEMPERATURE CHANGE OF 5 OR 6C FROM GLACIAL TO INTERGLACIAL TYPICALLY TAKES 5000 YEARS OR MORE; THE RATE OF WARMING IS GENERALLY LESS THAN 0.1C/CENTURY.
Well here is the evidence that temperatures went up at the end of the last deglaciation not by 5 OR 6 oC, but by a whopping 12.41 oC, in not 5,000 years but a mere 299 years.
So which is the false statement?
That is the important point not whether we are computing from anomalies or actual temperatures. DO YOU GET IT YOU -----?
Posted by: Richard | July 12, 2009 5:20 PM
"They don't claim that the Greenland ice core data says anything about global climate changes during those periods of time. Just the opposite,.." Oh really?
From:
http://en.wikipedia.org/wiki/Younger_Dryas#The_end_of_the_Younger_Dryas
"Measurements of oxygen isotopes from the GISP2 ice core suggest the ending of the Younger Dryas took place over just 40 – 50 years in three discrete steps, each lasting five years. Other proxy data, such as dust concentration, and snow accumulation, suggest an even more rapid transition, requiring a ~7 °C warming in just a few years;[5][6][14][15] the total warming was 10°±4°.[16]
The end of the Younger Dryas has been dated to around 9620 BC (11550 calendar years BP, occurring at 10000 radiocarbon years BP, a "radiocarbon plateau") by a variety of methods, with mostly consistent results:
11530±50 BP — GRIP ice core, Greenland [17]
11530+40-60 BP — Kråkenes Lake, western Norway. [18]
11570 BP — Cariaco Basin core, Venezuela [19]
11570 BP — German oak/pine dendrochronology [20]
11640±280 BP — GISP2 ice core, Greenland [14] "
From:
http://www.pnas.org/content/97/4/1331.full
"The Greenland records show that climate changes have been VERY LARGE, RAPID, AND WIDESPREAD."
"The relative changes in methane concentrations in Greenland and Antarctica indicate that the increase at the end of the Younger Dryas involved both tropical and high-latitude sources (24, 25), and that the previous large increase about 14,700 years ago was dominated by the tropics (25)."
"Other Greenland data also show that the climate changes were GEOGRAPHICALLY EXTENSIVE. The isotopic composition of dust in Greenland ice indicates an Asian source (19), and the sea salt is oceanic. The large changes observed in dust and sea salt indicate reorganizations of weather patterns well beyond Greenland."
Posted by: Richard | July 12, 2009 7:02 PM
If I might once again interrupt, might I ask the people around here, how accurate is this chart.
http://www.drroyspencer.com/wp-content/uploads/UAH_LT_1979_thru_Dec_09.jpg
I found this few days ago and I found it odd that is showed a rather stable line from 2002 to 2006, with hardly any warming from the first records from 1971. Now I might understand how the beginning can be explained by the misscalculation, but the later data shows on itself no clear warming when that El Nino is there.
Would someone be kind enough to help a newbie in need and clear this for me? Is this chart simply without accuracy or what am I missing?
Posted by: Riku | January 8, 2010 4:11 PM
Hi Riku,
First up, the data is too noisy to decide there are different regions like "flat since 2002". So one must do the simplest thing and take all 30 some years of data there and fit a straight line to it. That will definitely have a positive slope. My eyeball guess is that one would get 0.15 C/decade or a hair less. Let's say 0.13 to 0.15. The GISSTemp ocean-land surface numbers give something like 0.17 to 0.18 C/decade. So the UAH is showing warming, just a little slower than the GISSTemp data does.
Why might that be?
The UAH numbers are (by the nature of how the measurement is taken - I'd need someone more technical to explain this further, but it's because it's strongly affected by water vapor) more heavily weighted to counting the tropics than high latitudes. That's why the 1998 El Nino is so much bigger on satellite graphs than surface temperature graphs.
So, because global warming is strongest at high latitudes (aka "polar amplification") the UAH graph shows slower warming. It's showing the truth - lower latitudes are warming at a slower rate than high latitudes.
Posted by: GFW | January 8, 2010 8:43 PM
Oh that makes sense, thanks again GFW.
Posted by: Riku | January 9, 2010 1:08 AM