OK, so my art is a bit tongue in cheek. But it does fit the disaster theme of the topic.
This op-ed piece in the Herald Sun is interesting, because it touches on many of the points covered here on WUWT. This is the first time I’ve seen all these collected in one article in a major newspaper. Andrew Bolt routinely uses material from WUWT, and this is the first time I’ve been able to reciprocate. There are some truly unique points raised by Bolt that are indigenous to Australia that we haven’t discussed here, but they are valid for discussion nonetheless. In cases where we have covered a point on WUWT, I’ve made a footnote link [in brackets] – Anthony
From Andrew Bolt, The Herald Sun
Global Warming Alarmists Out in the Cold
April 29, 2009 12:00am
IT’S snowing in April. Ice is spreading in Antarctica. The Great Barrier Reef is as healthy as ever.
And that’s just the news of the past week. Truly, it never rains but it pours – and all over our global warming alarmists.
Time’s up for this absurd scaremongering. The fears are being contradicted by the facts, and more so by the week.
Doubt it? Then here’s a test.
Name just three clear signs the planet is warming as the alarmists claim it should. Just three. Chances are your “proofs” are in fact on my list of 10 Top Myths about global warming.And if your “proofs” indeed turn out to be false, don’t get angry with me.
Just ask yourself: Why do you still believe that man is heating the planet to hell? What evidence do you have?
So let’s see if facts matter more to you than faith, and observations more than predictions.
MYTH 1
THE WORLD IS WARMING
Wrong. It is true the world did warm between 1975 and 1998, but even Professor David Karoly, one of our leading alarmists, admitted this week “temperatures have dropped” since – “both in surface temperatures and in atmospheric temperatures measured from satellites”. In fact, the fall in temperatures from just 2002 has already wiped out a quarter of the warming our planet experienced last century. (Check data from Britain’s Hadley Centre, NASA’s Aqua satellite and the US National Climatic Data Centre.)
Some experts, such as Karoly, claim this proves nothing and the world will soon start warming again. Others, such as Professor Ian Plimer of Adelaide University, point out that so many years of cooling already contradict the theory that man’s rapidly increasing gases must drive up temperatures ever faster.
But that’s all theory. The question I’ve asked is: What signs can you actually see of the man-made warming that the alarmists predicted?
[ Ian Plimer, Temperature trends]
MYTH 2
THE POLAR CAPS ARE MELTING
Wrong. The British Antarctic Survey, working with NASA, last week confirmed ice around Antarctica has grown 100,000 sq km each decade for the past 30 years.
Long-term monitoring by the US National Oceanic and Atmospheric Administration reports the same: southern hemisphere ice has been expanding for decades.
As for the Arctic, wrong again.
The Arctic ice cap shrank badly two summers ago after years of steady decline, but has since largely recovered. Satellite data from NASA’s Marshall Space Flight Centre this week shows the Arctic hasn’t had this much April ice for at least seven years.
Norway’s Nansen Environmental and Remote Sensing Centre says the ice is now within the standard deviation range for 1979 to 2007.
[Antarctic Ice Growth, Arctic Ice Recovery ]
MYTH 3
WE’VE NEVER HAD SUCH A BAD DROUGHT
Wrong. A study released this month by the University of NSW Climate Change Research Centre confirms not only that we’ve had worse droughts, but this Big Dry is not caused by “global warming”, whether man-made or not.
As the university’s press release says: “The causes of southeastern Australia’s longest, most severe and damaging droughts have been discovered, with the surprise finding that they originate far away in the Indian Ocean.
“A team of Australian scientists has detailed for the first time how a phenomenon known as the Indian Ocean Dipole – a variable and irregular cycle of warming and cooling of ocean water – dictates whether moisture-bearing winds are carried across the southern half of Australia.”
MYTH 4
OUR CITIES HAVE NEVER BEEN HOTTER
Wrong. The alleged “record” temperature Melbourne set in January – 46.4 degrees – was in fact topped by the 47.2 degrees the city recorded in 1851. (See the Argus newspaper of February 8, 1851.)
And here’s another curious thing: Despite all this warming we’re alleged to have caused, Victoria’s highest temperature on record remains the 50.7 degrees that hit Mildura 103 years ago.
South Australia’s hottest day is still the 50.7 degrees Oodnadatta suffered 37 years ago. NSW’s high is still the 50 degrees recorded 70 years ago.
What’s more, not one of the world’s seven continents has set a record high temperature since 1974. Europe’s high remains the 50 degrees measured in Spain 128 years ago, before the invention of the first true car.
MYTH 5
THE SEAS ARE GETTING HOTTER
Wrong. If anything, the seas are getting colder. For five years, a network of 3175 automated bathythermographs has been deployed in the oceans by the Argo program, a collaboration between 50 agencies from 26 countries.
Warming believer Josh Willis, of NASA’s Jet Propulsion Laboratory, reluctantly concluded: “There has been a very slight cooling . . .”
MYTH 6
THE SEAS ARE RISING
Wrong. For almost three years, the seas have stopped rising, according to the Jason-1 satellite mission monitored by the University of Colorado.
That said, the seas have risen steadily and slowly for the past 10,000 years through natural warming, and will almost certainly resume soon.
But there is little sign of any accelerated rises, even off Tuvalu or the Maldives, islands often said to be most threatened with drowning.
Professor Nils-Axel Moerner, one of the world’s most famous experts on sea levels, has studied the Maldives in particular and concluded there has been no net rise there for 1250 years.
Venice is still above water.
[Sea Level in the Maldives, Sea Level satellite data]
MYTH 7
CYCLONES ARE GETTING WORSE
Wrong. Ryan Maue of Florida State University recently measured the frequency, intensity and duration of all hurricanes and cyclones to compile an Accumulated Cyclone Energy Index.
His findings? The energy index is at its lowest level for more than 30 years.
The World Meteorological Organisation, in its latest statement on cyclones, said it was impossible to say if they were affected by man’s gases: “Though there is evidence both for and against the existence of a detectable anthropogenic signal in the tropical cyclone climate record to date, no firm conclusion can be made on this point.”
[Ryan Maue and Hurricane energy, Hurricane landfall trends]
MYTH 8
THE GREAT BARRIER REEF IS DYING
Wrong. Yes, in 1999, Professor Ove Hoegh-Gulberg, our leading reef alarmist and administrator of more than $30 million in warming grants, did claim the reef was threatened by warming, and much had turned white.
But he then had to admit it had made a “surprising” recovery.
Yes, in 2006 he again warned high temperatures meant “between 30 and 40 per cent of coral on Queensland’s Great Barrier Reef could die within a month”.
But he later admitted this bleaching had “minimal impact”. Yes, in 2007 he again warned that temperature changes of the kind caused by global warming were bleaching the reef.
But this month fellow Queensland University researchers admitted in a study that reef coral had once more made a “spectacular recovery”, with “abundant corals re-established in a single year”. The reef is blooming.
MYTH 9
OUR SNOW SEASONS ARE SHORTER
Wrong. Poor snow falls in 2003 set off a rash of headlines predicting warming doom. The CSIRO typically fed the hysteria by claiming global warming would strip resorts of up to a quarter of their snow by 2018.
Yet the past two years have been bumper seasons for Victoria’s snow resorts, and this year could be just as good, with snow already falling in NSW and Victoria this past week.
[New low temp record at Australian ski resort this year]
MYTH 10
TSUNAMIS AND OTHER DISASTERS ARE GETTING WORSE
Are you insane? Tsunamis are in fact caused by earthquakes. Yet there was World Vision boss Tim Costello last week, claiming that Asia was a “region, thanks to climate change, that has far more cyclones, tsunamis, droughts”.
Wrong, wrong and wrong, Tim. But what do facts matter now to a warming evangelist when the cause is so just?
And so any disaster is now blamed on man-made warming the way they once were on Satan. See for yourself on www.numberwatch.co.uk/warmlist.htm the full list, including kidney stones, volcanic eruptions, lousy wine, insomnia, bad tempers, Vampire moths and bubonic plagues. Nothing is too far-fetched to be seized upon by carpetbaggers and wild preachers as signs of a warming we can’t actually see.
Not for nothing are polar bears the perfect symbol of this faith – bears said to be threatened by warming, when their numbers have in fact increased.
Bottom line: fewer people now die from extreme weather events, whether cyclones, floods or blinding heatwaves.
Read that in a study by Indur Goklany, who represented the US at the Intergovernmental Panel on Climate Change: “There is no signal in the mortality data to indicate increases in the overall frequencies or severities of extreme weather events, despite large increases in the population at risk.”
[Going down – death rates due to extreme weather events]
So stop this crazy panic.
First step: check again your list of the signs you thought you saw of global warming. How many are true? What do you think, and why do you think it?
Yes, the world may resume warming in one year or 100. But it hasn’t been warming as the alarmists said it must if man were to blame, and certainly not as the media breathlessly keeps claiming.
Best we all just settle down, then, and wait for the proof — the real proof. After all, panicking over invisible things is so undignified, don’t you think?
crosspatch (20:15:38) :
In the next glaciation the Great Barrier Reef will, as it did in the last glaciation, be completely dead as it will be hundreds of feet above sea level. There will be nothing we can do to “save” it. The same will be true for practically every other coral reef we know of today, too.
That’s very sad, another ephemeral entity consigned to the dustbin of deep time. I think that I’ll just go off and have a quiet cry into my beer.
Sandy: “The internet has taken peer review to a whole new level, so with the BS exposed and the world cooling, the death-throes of AGW are upon us.”
When you say “the death-throes of AGW are upon us”, by “upon us” do you mean now, next month, next year, in five years’ time?
I’d like to be prepared for the AGW death throes, the collapsing house of cards, the turning point, the bursting bubble, the rats jumping ship, the last gasp, the veneer cracking, the edifice crumbling, the game ending, or even just the end beginning.
For hareynolds
“This reminds me of the old Nevil Shute book (and movie with Ava Gardner!) ON THE BEACH, in which the Ozzies are the last folks alive after a global nuclear holocaust.”
And when Ava Gardner arrived in Oz she is reported to have said: “I have come to Australia to make a film about the end of the Earth and my first impression is that I have come to the right place!”
Smokey, ~snip~ You can’t measure climate change over 10 years.
How old are you, Smokey? ~snip~ I am beginning to think you must be very young. I am talking to you as if you are an adult, and quite possibly you’re not.
Young? Wrong as always, RW. I’m mature [but not old! ;^) ] enough to have retired after a 30+ year career as a professional metrologist, designing, calibrating, testing and repairing weather/climate related instruments, primarily those measuring temperature, the dew/frost point, relative humidity, etc.
The laboratory I worked in had over 140 engineers and technicians, and none of them — not a single one — bought into Al Gore’s globaloney warming scam, which you apparently have, hook, line and sinker. These were professionals, working in the hard sciences. Raises and promotions were dependent on our being right, rather than being politically correct.
If someone had come in and voiced some of your opinions, he would have been laughed out of the lab. We had a sign on the lab wall: “One Test Is Worth A Thousand Expert Opinions”. You would not have made it there.
I’ve asked you for your CV several times now, but you always avoid admitting what it is. That tells me all I need to know. Without a background in the subject, it’s always best to ask technical questions, rather than making blanket statements as if they are unassailable. The result of making those statements can be seen here [scroll down and read the first dozen or so comments. Seems other people hold RW in pretty low esteem].
If you believe that you’re convincing anyone, well, you can see from their comments that you’re not. CD again. My sympathy.
~snip~ ad hominem. What is your explanation for the declining 13C content of atmospheric CO2?
Alexej Buergin:
“Did you notice that the ordinate of your curve starts at 270 ppm, which makes the changes look much bigger than they are?”
A 40% increase is a 40% increase, no matter what axes you choose.
“But of course I should have defined “SIGNIFICANTLY” (2.5 SD ?). And I should have asked “significantly OVER THE MEAN”.”
Why don’t you get hold of the data, and do these calculations yourself?
MikeN: what is the scientific relevance of your statement about 1998?
Alexej Buergin:
“Did you notice that the ordinate of your curve starts at 270 ppm, which makes the changes look much bigger than they are?”
RW:
A 40% increase is a 40% increase, no matter what axes you choose.
“But of course I should have defined “SIGNIFICANTLY” (2.5 SD ?). And I should have asked “significantly OVER THE MEAN”.”
Why don’t you get hold of the data, and do these calculations yourself?
The answer is of course: I am too lazy to transfer a large table of numbers (Excel would do the calculations), so let us stick to (your) use of %.
Let us define “significant” as a rise of 10% over the average. That takes us to about 310 ppm. Which corresponds to about 1950 when the so called AGW usually is supposed to have started.
Your definition of significant is entirely arbitrary. Look at the data. The sharp rise quite obviously did not start in 1950.
>MikeN: what is the scientific relevance of your statement about 1998?
None, someone posted a link claiming a decade trend of increase, and I note that if you change the start point slightly, you get the opposite, so their claim is bogus.
You still haven’t explained why you think things have gotten cooler.
If your point was to show that short periods are irrelevant to discussions about climate, then I agree with you.
“You still haven’t explained why you think things have gotten cooler.”
I don’t think that.
MikeN:
Don’t know who did that, but I agree with MikeN and the scientific community in general that global temps are not increasing.
I can’t explain exactly why the planet is cooling, either. I suspect that it’s just fluctuating around its natural trend line. But I do know that rising carbon dioxide levels have little effect on temperature: click
The fact that since about 2002, global temperatures have been falling means that the planet itself is falsifying any significant CO2 effect.
Of course someone could come along and claim that seven years of falling temperatures mean nothing because only a 30-year chart is significant: click. We are within about 0.2° C up from 1979. If someone wants to argue that a 0.2° C change is outside of normal and natural variation, bring it on.
The current round of warmist arm-waving began in earnest around 1997, when temps rose about 0.8° C above the long term trend line. I began taking seriously the possibility that global warming [not AGW] could be a problem.
But as we’ve seen since then, 1997 was simply an anomaly. In retrospect, it was a false positive that sent shivers up the legs of the true believer crowd. They’ve been disappointed ever since, and now resort to insisting that the world must just take their word for it that they’re right. That’s not happening.
Finally, how can anyone take the UN/IPCC credibly, when they’re so far off base?
Well, that’s real progress, Smokey – yet more irrelevant graphs, but you now acknowledge the idea of internal variability swamping trends over periods of a few years, and the idea that climate takes more than ten years to measure. Your very first graph of a meaningful time period shows an upward trend of about 0.15°C/decade, not the 0.06°C that you claim, presumably on the basis of comparing two individual months rather that considering all the data.
1998 was not an anomaly. It was a year in which a very strong El Niño occurred. This semi-regular phenomenon is certain to happen again in the next 10-15 years. Given that the underlying trend in global temperatures is upward, the next time there is an El Niño of comparable magnitude to 1998’s, it is certain to result in a warmer year than 1998.
“I do know that rising carbon dioxide levels have little effect on temperature”
Wrong, as I’ve shown you before. To understand a problem you have to look at all the available data, not just a tiny bit you chose because it seemed to fit your preconceptions.
You never responded to those papers that I linked to, showing where the 40% rise in CO2 over the last 200 years has come from. Did you read them?
“RW (08:54:20) :
Your definition of significant is entirely arbitrary. Look at the data. The sharp rise quite obviously did not start in 1950.”
Of course it is arbitrary. That’s why, when you test a hypothesis, you decide on the level of significance before doing the calculation. That’s why I did not define it in my first post. Which gave you the possibility to omit it (the word “significantly”) in your response, so you could answer a question I did not ask. My question was and still is: From what point in time was the rise relevant?
The important point (in earth history) is that the rise in temperature always came a few hundred years before the rise in CO2-content.
RW: “1998 was not an anomaly.”
Huh?? You could look it up:
Of course 1997 was an anomaly. QED.
And no, I didn’t read your links. In addition, I reject all woodfortrees interactive charts, not because that isn’t a fun site, but because they are always cherry picked in your case to show what you want — while the numerous charts I provided in this thread came from many different sources. Those were not my charts; they were compiled by professionals in related fields. But there is not a single one out of more than two dozen charts I posted, which you haven’t arbitrarily rejected. Not one. That is extraordinarily unreasonable; no honest, reputable person would be that extreme or closed minded. Those professionals, organizations, governments and universities are not all wrong, in every case.
It’s clear to others beside me that your mind is made up and closed tight. You appear to be a crank. And you surely fail a basic credibility test by rejecting every chart issued by numerous legitimate sources.
As “Themstocles” commented about you in Jennifer Marohasy’s blog:
“I have noticed this RW person on other sceptic sites, where he engages in the same obnoxious behavior. Steve McIntyre completely deleted without comment quite a few similar RW posts recently from Climate Audit. Anthony Watts’ site is also plagued with similar fact free RW postings.”
And poster “groweg” says:
“RW: You have put yourself in the position of an ‘expert’ implying you have read atmospheric physics texts and responding dismissively and condescendingly to posts here. ‘Miskolczi’s work is ‘meaningless’ and Gary P’s opinions are ‘anti-science’, as if you are the arbiter of what is scientific…
“Gary P. has investigated this topic to some apparent depth and arrived at conclusions that are unique from those in the popular media. You, on the other hand, arrogate the mantle of science such that you feel you are in a position to dismiss Gary P. in a heavy-handed, rigid way as ‘anti-science’ (whatever that is) while adhering to the conventionally-accepted ‘wisdom’ on this topic. I do not claim to be any expert on climate science, but merely from the above considerations, I would pick Gary P.’s views as most likely correct. He’s also the one I’d rather have a beer with.”
Everyone commenting about RW thinks more or less the same way: “I would pick Gary P.’s views as most likely correct. He’s also the one I’d rather have a beer with.” Ya think??
There are other similar comments made there, and here, and at CA and elsewhere. So who is out of step? Everyone else? Is it reasonable accept as credible someone with a demonstrably closed mind? Someone who arbitrarily rejects 100% of any information that does not fit his own personal belief system? Someone who insistently demands that all others must step up and answer his questions — but who hides out from answering any uncomfortable questions from other posters? Someone who comes across as a crank?
No. It is not reasonable, in a debate over the article beginning this thread, to take the position that everyone who disagrees is always in the wrong. Those posters quoted above are not 100% wrong. Truth be told, they are pretty much right on the money. Neither am I 100% wrong, even though that is your repeatedly stated opinion. Nor are the other posters in this extensive thread 100% wrong, simply because you disagree with them.
I don’t think they’d want to have a beer with you, either.
(Smokey):
“I do know that rising carbon dioxide levels have little effect on temperature”
(RW):
Wrong, as I’ve SHOWN you before
The graph SHOWN proves nothing and is just plain silly. So temperature and CO2 went up during 50 years. But the manipulation of the units (missing) for CO2 is dishonest, as one can always make straight lines coincide (if necessary counting backwards on one of the ordinates).
If the rise in CO2 is the reason for the rise in temperature, one must show that the first mentioned started first. But it was always the other way around.
MarkT:
Having refereed over 80 papers in physics (and published about 30), I have a reasonably large amount of experience with peer review. And, if you are asking whether I think peer review is sufficient in the sense of a guarantee that any particular paper is correct and even that it doesn’t suffer from elementary errors, the answer is no. In fact, that is quite obvious, for example, from the fact that the Douglass et al paper passed peer review and that even the ridiculous polemical nonsense by Gerlich and Tscheuschner was published in a third-rate peer-reviewed physics journal.
However, the real point of peer review is not to guarantee the correctness of any particular paper but to increase the signal-to-noise ratio…and that I think it does quite well. And discussions at sites like this provide evidence of why that can be a good thing.
Alexej Buergin: it’s not clear what your point is. The data is clear, though. CO2 started rising in about 1750. The 13C content of atmospheric CO2 <a href=”“>started dropping around the same time. Are you trying to argue that rising temperatures caused the post-industrial rise in CO2?
Smokey: after a brief glimmer of hope, you’ve lapsed again. Your logic seems to be that if you can find enough people who say something, then that makes it right. Well, I can find you a hundred people who say the Earth is flat, a thousand people who say the moon landings didn’t happen, and a million people who think they’ve been abducted by aliens.
El Niño is a standard, normal and expected phenomenon.
None of your graphs came from governments or universities. They were all irrelevant except the one that showed temperatures since 1979. I don’t know why you struggle to understand this: a graph of the last 7 years, or 10 years, or 11 years, is always and in every case irrelevant, no matter who produced it and no matter how many of them you can find. You can’t measure a trend in global temperatures over these periods. Full stop. End of story.
“no, I didn’t read your links”
I’m not surprised. You are someone who arbitrarily rejects 100% of any information that does not fit his own personal belief system.
RW
I’ve avoided jumping in on this back and forth with Smokey, mostly because I’m busy, but to sum it up.
You don’t like Smokey’s graphs because the time period cannot reflect climate changes. He doesn’t like yours because you state the consensus view.
I would like to reframe this a bit. You do realize that the 30 year time period for “climactic significance” is an arbitrary choice? There is no physical basis or derived statistic that defines this choice. It is simply a holdover of previous choices used to define averages for weather records.
Rather than say the “Earth’s climate is cooling” would you be willing to state: “For the last seven years or so, surface measurements are showing a slight negative trend”? And I would be willing to state it’s been positive since last March.
The real question is: Are the trends we are observing sufficient to falsify the current theories which can be summed up with the term Anthropological Global Warming?
What would be required to insist that were true? Would it require 30 years of records? What observations need be made. In MY opinion, demonstrating that GCM’s are failing in the predictions or scenarios by a statistically significant amount would be important since the bedrock of AGW theory is the GCM’s.
Lucia over at rank exploits shows this over and over again..
Whether or not this is published by a university or not is not relevant. What would be relevant would be a valid critique of her work.
“You can’t measure a trend in global temperatures over these periods. Full stop. End of story.”
At what point can you call it a trend, 30 years?
Jeez: a trend only exists if it is larger than the error bars. For example, a ‘trend’ of +0.2 ± 0.5 is not a trend. A trend of +0.2 &pm 0.1, though, is a trend. Thus, there is a clear statistical basis for determining climatic significance.
Given that, no, I would not be willing to state that “For the last seven years or so, surface measurements are showing a slight negative trend”, and nor should you be willing to state that there has been any positive trend since last March. Over these periods, you cannot measure any trend.
“Are the trends we are observing sufficient to falsify the current theories which can be summed up with the term Anthropological Global Warming?”
Presuming that you’re referring to the last 7-10 years as “the trends we are observing”, well, we’re not observing any trends over that period. You can’t measure trends over that period. Starting from last month, and working backwards month by month, calculating a temperature trend from then until now, the first one you would find to be statistically significant would be positive.
“What would be required to insist that were true? Would it require 30 years of records? What observations need be made.”
A statistically significant downward trend that was not due to solar, volcanic or aerosol forcing would do.
“In MY opinion, demonstrating that GCM’s are failing in the predictions or scenarios by a statistically significant amount would be important since the bedrock of AGW theory is the GCM’s.”
I disagree that climate models are the bedrock of any theory. If they were all completely wrong, it would not change the fact that CO2 is a strong infrared absorber, the concentration of which has risen 40% due to fossil fuel burning. That is the bedrock of our understanding that humans have caused global temperatures to rise.
RW
Without the positive feedback explicitly included in GCMs the fears of the AGW crowd disappear, so yes, GCMs are the bedrock of AGW theory as far as any concern for the environment goes.
As far as the 40% increase due to fossil fuels, that is a longer discussion. BTW I do not dispute the fact the isotopic signatures identify that much of the CO2 circulating is fossil fuel sourced, however, without a real knowledge of sources and sinks-which we do not have, it is impossible to know that this increase in total concentration is primarily due to fossil fuels. There are many possibilities that this is simply a new equilibrium ratio and the total sum of CO2 is regulated by other factors.
Sandy says:
Depends what sort of precision you desire. I think a more precise statement than RW made would be to say that you can measure a trend in global temperature over any period that you want but you should also attempt to measure an errorbar for that trend. And, what you will find is that trends over a ten-year period still have quite large errorbars so that the result is actually compatible with a large range of underlying trends. (For trends over, say, 5 years the errorbars are, of course, even larger.) Certainly, by the time you get to a 30-year period, the errorbars are much smaller and so it is often said that periods close to this are necessary to define climate, but clearly it all comes down to the degree of precision desired.
“”” Micajah (16:18:58) :
I’ve seen things like this graph that indicate a plateau or possible decline in global temperature:
http://www.ncdc.noaa.gov/img/climate/research/global-jan-dec-error-bar-pg.gif
But, what is the source of this claim under “myth 1″? “In fact, the fall in temperatures from just 2002 has already wiped out half the warming our planet experienced last century.” Is it based on one month’s anomaly? For example, March 2009? “””
Micajah; look in the mirror. YOU are the source of that myth you cite. #1 on the above list claims only 1/4 of the last century retraced;
You and you alone, made up that myth about it being half.
George
jeez says:
And, tamino over at his blog has demonstrated otherwise. Since the results one gets for the trends and their significance seem to depend very strongly on the time period that one considers, his result seems more sensible to me.
“”” MikeN (20:48:58) :
This whole thing about global warming stopping in 1998, or that half the warming has been erased, are you really arguing that CO2 doesn’t cause an increase in temperatures? If the sun is responsible for the cooling, and overwhelming the CO2 trend, then wouldn’t a more active sun just restart the warming? “””
Well if the rising CO2 is responsible for the warming (after triggering massive positive feedback warming by water vapor); why isn’t it still warming since the CO2 is still going up, and there is plenty of water available for that wonderful positive feedback amplifier ?
And we have it on good authority that the sun doesn’t have anything to do with earth’s climate so don’t blame the sun for laying down on the job.
We know the CO2 is going up; you’ve drummed that into us; we know that CO2 causes runaway globale warming; you’ve drummed that into us as well; so where the blazes is the warming that we have bouth and paid for already.
Enquiring minds want to know; before we all freeze to death.
RW says:
I would add expand on this point in this way: Our understanding of the radiative effects of CO2 certainly allows us to know with good precision what the radiative forcing due to this rise is. So, then the question comes down to climate sensitivity to that forcing. While it is true that climate models are one source of estimates of that forcing, another important source is paleoclimate events, major volcanic eruptions like Mt Pinatubo, and to a lesser degree (mainly because of the high degree of uncertainty in regards to the aerosol forcing) the 20th century temperature record. All of these suggest that the net feedbacks are positive, producing an equilibrium sensitivity likely in the range of about 2 to 4 C per doubling of CO2 (or roughly 0.5 to 1 C per W/m^2 of forcing). In fact, a net negative feedback such as that proposed by Spencer would require a complete rewriting of our understanding of paleoclimate. (My guess is that it may also be hard to reconcile with current climatology too although I am less sure about that.)