To the IPCC: Forget about "30 years"

IPCC has never waited for 30-year trends, and they were right.

Guest essay by Barry Brill

Under pressure at a media conference following release of its Summary for Policymakers, AR5 WG1 Co-Chair Thomas Stocker is reported to have said that “climate trends should not be considered for periods less than 30 years”.

Some have seen this as the beginning of an IPCC ploy to continue ignoring the 16-year-old temperature standstill for many years into the future. But even the IPCC must know that any such red herring is dead in the water:

1. When James Hansen launched the global warming scare in 1988, there had been no statistically significant warming over the previous 30 years and the warming trend during 1977-87 was 0.0°C. The IPCC was also established that year.

1977-1987_GISS

Source: Woodfortrees plot

2. At the time of the first IPCC report in 1991 (FAR), the warming trend was barely 11 years old.

1977-1991_GISS

Source: Woodfortrees plot

3. Most significantly, the Rio Earth Summit in 1992 adopted the UNFCCC treaty on the basis of a 30-year cooling trend followed by only 12 years of warming. That treaty dogmatically redefined “climate change” as being anthropogenic and eventually committed over 190 countries to combat “dangerous” warming.

4. The latest WG1 report bases its assessment of sea level rise and ocean heat content on the trend in satellite readings which have been available for only 19 years, coupled with ARGO reports for a period less than a decade. There is no apology for the short periods.

5. In 2007, the AR4 made much of the fact that the warming trend over the previous 15 years exceeded 0.2°C/decade. In 2013, the AR5 plays down the fact that there is no significant warming at all during the previous 15 years. (But AR5 cites 0.05°C/decade without mentioning that this figure is ±0.14°C).

6. If the IPCC wants to focus on 30-year trends, why did it make no comment on the fact that the current 30-year trend has fallen to 0.174°C/decade from the 0.182°C/decade trend that was the (1992-2006) backdrop to the AR4? Particularly, as the intervening 6-year period has been characterised by record increases in CO2 emissions.

7. Dr Stocker’s criticism of short-term trends as being influenced by start and end dates, ignores that long-term trends are similar. He picked a 60-year period (1951-2010) to produce a 0.12°C/decade trend, when a 70-year or 80-year period would have shown a much-reduced trend of 0.07°C.

8. WG1 scientists found it appropriate to include a statement in the AR5 SPM that

“Models do not generally reproduce the observed reduction in surface warming trend over the last 10 –15 years.”

3 months later, this crucial sentence was disappeared by a secret conclave of politicians/bureaucrats – not by scientists.

9. Dr Jarraud, secretary-general of the World Meteorological Organisation (WMO), told journalist David Rose that his question about the standstill was “ill-posed”. The WMO issues manuals on best practice for climatology and regards itself as the premier authority on measuring temperature trends. Here is what its manual WMO GUIDE TO CLIMATOLOGICAL PRACTICES (3RD EDTN) has to say about 30-year periods:

Chapter 4.8.1 Period of calculation“A number of studies have found that 30 years is not generally the optimal averaging period for normals used for prediction. The optimal period for temperatures is often substantially shorter than 30 years, but the optimal period for precipitation is often subtantially greater than 30 years.”And (at page 102):“The optimal length of record for predictive use of normals varies with element, geography, and secular trend. In general, the most recent 5‑ to 10‑year period of record has as much predictive value as a 30‑year record.”

Prior to release of the SPM, Bloomberg reported that some countries (notably Germany) wanted to wholly ignore the temperature standstill and pretend that the 20-year-old paradigm was still intact.

Few expected that would happen, predicting a sharply-reduced best estimate of sensitivity and rueful acknowledgment that natural factors had been under-estimated. The fact that days of debate culminated in this absurd canard about 30-year trends is a powerful indicator of just how desperate the climate establishment has now become.

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ImranCan

The IPCC represents a dying ideology long bereft of honesty, integrity or respect for the intelligence of the human race.

Jimbo

Thomas Stocker is reported to have said that “climate trends should not be considered for periods less than 30 years”.

When I read this I decided to to see what I could find in the IPCC Summary For Policy Makers. Here are just a few results from the first 5 pages out of the total of 36 pages.

PCC Fifth Assessment Report
Climate Change 2013:
The Physical Science Basis Summary for Policymakers
……. The globally averaged combined land and ocean surface temperature data as calculated by a linear trend, show a warming of 0.85 [0.65 to 1.06] °C3, over the period 1880–2012, when multiple independently produced datasets exist. The total increase between the average of the1850–1900 period and the 2003–2012 period is 0.78 [0.72 to 0.85] °C, based on the single longest dataset available4. (Figure SPM.1a) {2.4} …….
…..5Trends for 15-year periods starting in 1995, 1996, and 1997 are 0.13 [0.02 to 0.24], 0.14 [0.03 to 0.24],0.07 [–0.02 to 0.18] °C per decade, respectively…..
Projections in the AR5 are relative to the reference period of 1986–2005, and use the new Representative Concentration Pathway (RCP) scenarios (see Box SPM.1)…
……..It is likely that the ocean warmed between 700 and 2000 m from 1957 to 2009. Sufficient observations are available for the period 1992 to 2005 for a global assessment of temperature change below 2000 m. …..
…..The average rate of ice loss8 from glaciers around the world, excluding glaciers on the periphery of the ice sheets9, was very likely 226 [91 to 361] Gt yr−1 over the period 1971−2009, and very likely275 [140 to 410] Gt yr−1 over the period 1993−2009 10. {4.3} …..
….. The average rate of ice loss from the Greenland ice sheet has very likely substantially increased from 34 [–6 to 74] Gt yr–1 over the period 1992–2001 to 215 [157 to 274] Gt yr–1over the period 2002–2011. {4.4} …..
http://www.climatechange2013.org/images/uploads/WGIAR5-SPM_Approved27Sep2013.pdf

Jimbo

Further to my last comment can you imagine the number of periods less than 30 years in the full IPCC report? Thomas Stocker was caught off guard.

M Courtney

To put the thirty years in context it is worth remembering that the Summary does not mention a requirement for thirty years’ worth of trend and this post shows why. So where does it come from?
The response, that claims you need about twenty to thirty years of trend, came about because Rose of the Daily Mail asked how long it would take to falsify the climate models.
The significance of the unprepared answer is not that the answer was wrong but that it was unprepared.
There should be a way to falsify a model if it is scientific model. There was no prepared answer because the climate models are not falsifiable.
They express faith not knowledge.
Of course trends shorter than 30 years are used by the IPCC. The whole “we lost the heat in the deep sea, whoops” argument depends on the ARGO floats that aren’t thirty years old. But there are worse things wrong with Thomas Stocker’s evasion than that.

AndyG55

We need to also remember that around 1991 is when Hansen started making wholesale adjustments to the GISS record…
How much of that trend was real, and how much was created !!!

lemiere jacques

Well, 30 years for averaging local parameters such as rain falls, or temperatures, but for a real physical parameter supposed to be “constant” such as total energy there is no reason to process in the same way.
All is about what people call natural variablity, it means that they assume is a sort of equilibriulm state of climate only depending on external/gloabl forcings exits…how can they be sure about that???

“Prior to release of the SPM, Bloomberg reported that some countries (notably Germany) wanted to wholly ignore the temperature standstill and pretend that the 20-year-old paradigm was still intact.”
Makes sense that Germany would want to do this considering the massive sums of money they have committed to alternative energy (mainly wind and solar). It is far too politically embarrassing to admit that you’ve made that commitment on the basis of a false CAGW narrative.
Here in the U.S. we have committed billions to wind and solar as well, but not as much of our budget as Germany and other European countries. They’ve gotten themselves in a deep hole now. Sooner or later, they will all have to stop digging it deeper and crawl out of it. It’s just a matter of when rather than if.

M Courtney:
This is one of those rare occasions when I agree with you.
In your post at September 30, 2013 at 4:11 am you accurately identify how and why the ‘30-year period excuse occurred’. And you conclude saying

Of course trends shorter than 30 years are used by the IPCC. The whole “we lost the heat in the deep sea, whoops” argument depends on the ARGO floats that aren’t thirty years old. But there are worse things wrong with Thomas Stocker’s evasion than that.

Yes, and the worst is that the previous IPCC Report made a prediction (n.b. NOT a “projection”) “the first two decades of the 21st century” which is already proven wrong by the halt in global temperature change.
The explanation for this is in IPCC AR4 (2007) Chapter 10.7 which can be read at
http://www.ipcc.ch/publications_and_data/ar4/wg1/en/ch10s10-7.html
It says there

The multi-model average warming for all radiative forcing agents held constant at year 2000 (reported earlier for several of the models by Meehl et al., 2005c), is about 0.6°C for the period 2090 to 2099 relative to the 1980 to 1999 reference period. This is roughly the magnitude of warming simulated in the 20th century. Applying the same uncertainty assessment as for the SRES scenarios in Fig. 10.29 (–40 to +60%), the likely uncertainty range is 0.3°C to 0.9°C. Hansen et al. (2005a) calculate the current energy imbalance of the Earth to be 0.85 W m–2, implying that the unrealised global warming is about 0.6°C without any further increase in radiative forcing. The committed warming trend values show a rate of warming averaged over the first two decades of the 21st century of about 0.1°C per decade, due mainly to the slow response of the oceans. About twice as much warming (0.2°C per decade) would be expected if emissions are within the range of the SRES scenarios.

In other words, it was expected that global temperature would rise at an average rate of “0.2°C per decade” over the first two decades of this century with half of this rise being due to atmospheric GHG emissions which were already in the system.
This assertion of “committed warming” should have had large uncertainty because the Report was published in 2007 and there was then no indication of any global temperature rise over the previous 7 years. There has still not been any rise and we are now way past the half-way mark of the “first two decades of the 21st century”.
So, if this “committed warming” is to occur such as to provide a rise of 0.2°C per decade by 2020 then global temperature would need to rise over the next 6 years by about 0.4°C. And this assumes the “average” rise over the two decades is the difference between the temperatures at 2000 and 2020. If the average rise of each of the two decades is assumed to be the “average” (i.e. linear trend) over those two decades then global temperature now needs to rise before 2020 by more than it rose over the entire twentieth century. It only rose ~0.8°C over the entire twentieth century.
Simply, the “committed warming” has disappeared (perhaps it has eloped with Trenberth’s ‘missing heat’?).
This disappearance of the “committed warming” is – of itself – sufficient to falsify the AGW hypothesis as emulated by climate models. If we reach 2020 without any detection of the “committed warming” then it will be 100% certain that all projections of global warming are complete bunkum. And that is before the next IPCC Report (AR6) is scheduled.
Richard

Kev-in-Uk

lemiere jacques says:
September 30, 2013 at 4:13 am
Well yes – that is the whole basis of the AGW meme – that everything is pretty well constant (except [anything] derived from CO2, of course) and therefore all and any changes are most likely the result of CO2 and hence are anthropogenic. There are so many flaws in this basic reasoning it defies belief. In some ways it saddens me that the alarmists have drawn the skeptic scientists into arguning on the warmistas ‘terms’ – because the fundemental assumptions of AGW ‘theory’ are false – and demonstrably so, because we know there is a very large degree of natural variability. This simple fact shoots down the majority of AGW scientific basis simply because we cannot (and will likely never be able to) discern a human signal from the natural variability without many many decades of very good data……the warmista use short term data to suit, and make claims that data is too long [or] too short according to which argument they are using at the time. In truth, ALL such arguments cannot be scientifically supported.

pesadia

Rajenda Pachuari wearing a sandwich board with the message which reads:
“IPCC predicts humanity is doomed”
Meets Realist wearing similar sandwich board which reads:
“RIPCC humanity will not be attending your funeral.

Greg

This is not about trends , it’s about divergence. The observational data is now outside the confidence levels given for the model predictions. That matters _now_ , we do not need to wait another 5 ,10 , 15 or 20 years. The models have failed.

kadaka (KD Knoebel)

1. When James Hansen launched the global warming scare in 1988, there had been no statistically significant warming over the previous 30 years and the warming trend during 1977-87 was 0.0°C. (…)
and
2. At the time of the first IPCC report in 1991 (FAR), the warming trend was barely 11 years old.
You didn’t prove that. You’re using GISTEMP LOTI and have referred to WFT, which presumably is using the most current GISTEMP LOTI version for your plots.
GISTEMP has been re-masticated, re-ingested, re-digested, and re-excreted so many times, it cannot be said that the past it shows now is the past that it showed in the past, nor that it shows what actually occurred.
Currently it shows if you shift that range forward just two years to 1979-1989, the warming has surged to 0.90°C/century according to GISTEMP.
http://www.woodfortrees.org/plot/gistemp/from:1979/to:1989/plot/gistemp/from:1979/to:1989/trend

Greg:
re your post at September 30, 2013 at 4:34 am.
Yes, the models have failed. Indeed, for years I have known the models are failures because in 1999 I published on why the Hadley Center GCM does not model the climate system of the real Earth, and in 2007 Kiehl published that a variety of climate models are similarly wrong.
But the important point is that the disappearance of the “committed warming” falsifies the hypothesis of AGW which the models attempt to emulate. The ’30 year excuse’ attempts to hide the fact that the AGW-hypothesis is falsified by the halt in global temperature change.
(see my post at September 30, 2013 at 4:27 am
http://wattsupwiththat.com/2013/09/30/to-the-ipcc-forget-about-30-years/#comment-1431679 )
Richard

Ian W

This is arguing science against politics. The SPM just has to allow the CAGW politicians to hold their positions for another few years. EPA in the US and the EC in the EU will continue even more rigidly enforcing new ‘carbon’ emissions and creating new taxes. With the failed media happily and uncritically chanting the press releases. As all the SPM chicanery was going on in Stockholm another UN group under pressure from the EC was creating a new carbon emissions trading scheme worldwide on all aircraft.
Do not fool yourselves that by deconstructing the SPM here or in ‘friendly’ media that the politicians or their bureaucracies will stop. The only thing that will grudgingly stop them is if as in Australia the politicians are voted out and those taking power take immediate action to curtail the bureaucracies that have been built. This will NOT be possible in the EU there is no mechanism to remove or stop the bureaucrats pushing carbon limits and carbon emissions taxes and trading. There will be great difficulty in the USA even with a landslide to Republicans in stopping the EPA killing industry and power generation by regulation. Behind both the EU and USA regulatory activities are a large number of financial institutions hoping to make fortunes salami slicing ‘their share’ of carbon tax monies and running their operation who are promising untold riches to politicians and bureaucrats, These are supporting questionable ‘green energy’ schemes and subsidies that worldwide run into trillions of dollars of laundering schemes to political ‘supporters’.
Does anyone really think that this will be stopped by saying – but you said previously climate metrics over 10 years was good enough?

Thanks, Barry. Good article.
Trends in a chaotic systems have little predictive value. Trends evaluate the past, the lenght of the trend is part of the evaluation.
The IPCC has commited suicide by publishing AR5. Weasel language is suspect from the go.

The 30 year trend makes sense only if the IPCC accepts that primary driver of the climate change is natural variability, i.e. the AMO and the PDO.
If so, I welcome the Thomas Stocker’s initiative to covertly disassociate ‘future IPCC thinking’ from now falsified ‘forever rising global temperatures in step with the rising CO2 atmospheric content’ and start serious study of the natural variability

chris y

This is an excellent post. Although Hansen’s 1988 testimony was a significant event, he was already dead certain years before, using a 15 year warming trend.
In 1981, Hansen relied on 15 years of temperature change as his ‘dramatic evidence’ of global warming- “They have found that the Earth’s average temperature rose 0.2 degrees Centigrade from the mid-1960s to 1980.”- Eleanor Randolph, in The Pittsburgh Press, August 15, 1981
There are several problems with this. First, from 1965 to 1980, HadCRUT now gives 0.06C rise, GISS now gives 0.12C rise and HadSST now gives 0.02C DROP. So, Hansen hung his hat on a temperature increase that is smaller than the noise in the measurement. Remarkably, he was fitting the flat tail of an exponential curve to noise. Second, we now have 15 years of no temperature increase, while annual CO2 emissions are 2.5 times higher. Third, Hansen started his 15 year temperature trend in the mid 1960’s, right after the Class 5 eruption of Agung. Presumably Hansen would never have exploited a volcanic temperature dip at the beginning of the trend. Presumably Hansen felt it ‘didn’t matter.’ Yet Hansen now blames aerosols from almost nonexistent volcanic eruptions to explain the pause in temperature rise over the recent 15 years.

chris y

Paul Ehrlich testimony 1974, page 269 indicates that he was comfortable using less than 15 years of temperature data (1960 to 1974) to clang the cooling climate cowbell-
“When meteorologists talk about normal weather, by convention internationally they’re talking about the average weather period 1930 to 1960. It turns out that was the most extreme period of good weather in the last 1000 years. We are now clearly coming down off of that peak.”
From the 1974 Senate testimony of Paul Ehrlich and John Holdren in hearings on the “Domestic Supply Information Act” held by the Committee on Commerce and Committee on Government Operations (Serial No. 93-107).

Fabi

Further undermining their credibility, re: decades-long trends, is their recent attribution of seasonal events or even single occurrences to proclaim as evidence of global warming, e.g., Colorado flood, US west coast wildfires.

oakwood

While the SPM and associated spin are helping the warmists in winning the public arguments for now, there must surely be a good handful of AGW-faithful scientists who were waiting for the IPCC to truly tackle the pause ‘head on’, but are thinking – er, is that it?
As we know, all good scientists are sceptical.

Ian W:
I completely agree with your post at September 30, 2013 at 4:46 am
http://wattsupwiththat.com/2013/09/30/to-the-ipcc-forget-about-30-years/#comment-1431697
Indeed, I have repeatedly said the need now is to mobilise people with real expertise in political activity (e.g. Lords Lawson and Monckton, Senator Inhoffe, ex-President Klaus, etc.).
However, the media will continue to assert that the IPCC presents scientific information on AGW. It is necessary to clearly determine the information which demonstrates that assertion is a falsehood so the assertion can be refuted. For example, in this thread Greg W states how we know the climate models are falsified, and I state how we know the AGW hypothesis is falsified. The ’30-year-period-excuse’ is an attempt to obscure those falsifications and, thus, to defend the political promotion of AGW from refutation of its supporting pseudoscience.
Richard

M Courtney

The problem is that , yes, the science can be proven to be pseudoscience by its lack of falsifiability but, no, that doesn’t matter.
The [proponents] in the political world don’t care if the science is false. They will just ignore the inconvenient information and use the enthusiasm that they have whipped up. The science is just a tool to be used to politicians. And a tool they can no longer dare to put down having taught the next generation of voters that to doubt the impending doom is evil.
Politicians have no interest in a quest for truth.
Sadly that goes for Journalists too, which is less explicable.
(Although here is a guess as to why from my experience of [still] being pre-moderated at the Guardian. I, and others, are unable to dispute the catastrophists who have thus created a small focussed community – that may be a useful product for marketing purposes).

Stefan

@Ian W
I wish there was a thorough mapping out of the links between all the organisations involved, and how it all relates to the overall aim.
Is it about global governance (and a government needs a taxation system) ?
And to what end… I mean, what developing nations would relinquish control to a global government?

Lars Tuff

95% of IPCCs scientists can agree on this:
They have data models that can predict a) the human effects on climate with 1% certainty, b) the natural effects on climate with 1% certainty, so this leads to the conclusion that their models fail to predict climate with 98% certainty, either the cause being man or nature, for the period 1951-2012.
This can be derived from their claims of 95% certainty that humans have caused 50% of the climate change in the period (that is: nature 50%), and the simple fact that only 2% of all their runs of climate models are able to correctly predict the most recent temperature development; The stasis in 1998-2012.
So therefore, 95% of IPCCs own scientists admit that their models failed to predict climate, with 98% ‘success’, in the period 1951-2012. Is this progress? Can anyone believe their propaganda any more?
In trying to hide the temp flattening, they have exposed that their models are useless, and even though they have 98% faith in their own models failing, they still believe they can attribute 50% of climate change to humans. But mind You, they are only 1% certain of this… Remarkable.
When foolishly trying to explain the lack of temp rise in the period mentioned above, they use volcanoes and warming of the deep oceans as an excuse. This however, is a total surrender to natural causes of climate variability, argued for by the skeptics for 30+ years. Volcanoes are not caused by human emission of CO2, and the deep oceans can emit heat in everything from 1 to 2000 years. The deep ocean heat also, can not be measured correctly by anyone yet.
I can not see the 5th report as anything but a total surrender of the IPCC.
[“They have data models” or “They have data models …”? Mod]

pat

what to make of this?
30 Sept: BusinessSpectator: Tristan Edis: IPCC – a primer for conspiracy theorists
How did all this come about, you might ask?
Well, the story explained to me by Neville Nicholls, past-president of the Australian Meteorological and Oceanographic Society, suggests something rather innocent. Back in the 1980s at a conference of meteorologists, one hailing from Africa complained she was getting lots of requests for information from her government on the possible impacts of human-induced global warming. She wasn’t well equipped or resourced to answer them. She asked whether it might be possible for the meteorologists to arrange an assessment that could summarise what was known about global warming, which could be used by governments such as her own. And so the IPCC Assessment report process was born…
http://www.businessspectator.com.au/article/2013/9/30/science-environment/ipcc-primer-conspiracy-theorists
Nicholls missed an opportunity here to tell the tale of the African Meteorologist himself:
24 Sept: Monash: Neville Nicholls: Explainer: what is the IPCC anyway, and how does it work?Professor Nicholls is the immediate Past-President of the Australian Meteorological and Oceanographic Society and was a Coordinating Lead Author for the Intergovernmental Panel on Climate Change (IPCC) Special Report “Managing the risks of extreme events and disasters to advance climate change adaptation” that was completed in 2011.
http://monash.edu/news/show/explainer-what-is-the-ipcc-anyway-and-how-does-it-work
——————————————————————————–

herkimer

T o wait 30 years to be told an historical fact is ony of use to the historians . The science that can look at much shorter trends and make projections for the near term environment is what really matters . Would you wait 30 years before you are told that the market has gone down before you take action

Reminds me of the expression “don’t bother me with the facts”. It is amazing how all the hysteria is based on the warming during the 1980’s and a projection that rate would continue until doomsday. I find it unfortunate that most of the media is still buying the IPCC garbage as gospel. I saw that on the Weather Channel yesterday. Only Fox gets it right here in the US.

herkimer:
Sorry, but you completely fail to understand the existing situation when you make your post at September 30, 2013 at 5:59 am which says in total

T o wait 30 years to be told an historical fact is ony of use to the historians . The science that can look at much shorter trends and make projections for the near term environment is what really matters . Would you wait 30 years before you are told that the market has gone down before you take action

The AGW-scare was killed at the failed 2009 IPCC Conference in Copenhagen. I said then – and I have repeatedly said since – that the scare would continue to move as though alive in similar manner to a beheaded chicken running around a farmyard. It continues to provide the movements of life but it is already dead. And its deathly movements provide an especial problem.
Nobody will declare the AGW-scare dead: it will slowly fade away. This is similar to the ‘acid rain’ scare of the 1980s. Few remember that scare unless reminded of it but its effects still have effects; e.g. the Large Combustion Plant Directive (LCPD) exists. Importantly, the bureaucracy which the EU established to operate the LCPD still exists. And those bureaucrats justify their jobs by imposing ever more stringent, always more pointless, and extremely expensive emission limits which are causing enforced closure of UK power stations.
Bureaucracies are difficult to eradicate and impossible to nullify.
As the AGW-scare fades away those in ‘prime positions’ will attempt to establish rules and bureaucracies to impose those rules which provide immortality to their objectives. Guarding against those attempts now needs to be a serious activity.
The ’30-year-excuse’ is provided by bureaucrats to ‘buy time’ which keeps the defenestrated chicken running while they rush to establish the bureaucracies before the ‘chicken’ falls over and stops moving.
Richard

Graham

AR4 says: “The multi-model average warming for all radiative forcing agents held constant at year 2000”.
The earth’s albedo changes with the clouds from minute to minute, hour to hour and day to day. Their whole church is based on a constant albedo, but a quick look into the sky confirms that indeed clouds do form, dissipate and move about.
They fail by assigning a constant value to a dynamic variable: The albedo.
Their pseudo science has no answer to this, and neither have their activists. It’s a very basic, simple and devastating fault right in there at the core belief.

Kev-in-Uk

herkimer says:
September 30, 2013 at 5:59 am
From your post – it seems you are prepared to bet/accept policy on short term trends, yes? In that case, perhaps you can clear this with the alarmist crowd as a sensible approach because – lo and behold, we are in a flat/cool period, and fairly likely to cool further. Bingo ! – you have convinced me that AGW is definitely deceased and all the carbon environmental crapola is just that !

David in Michigan

I’m late to this thread but I am hoping someone will see this and respond. Various time periods for the “no warming” trend have been put forth…… 10 year, 15 years, 17 years. Why is there no agreement on the length of the period?? Can someone explain ? Anybody……

Latitude

“climate trends should not be considered for periods less than 30 years”.
===============
In that case, that would be the entire satellite record….
…and there has been no warming for the majority of the satellite record
http://stevengoddard.wordpress.com/2013/09/30/no-warming-for-the-majority-of-the-satellite-era/

knr

Sorry but you need to understand that the ‘time scale ‘ is itself a function of what the result does for ‘the cause ‘. Therefore, there is no ‘time scale ‘ requirement for that which supports ‘the cause ‘ while the time scale requirement for that which challenges it is 0 to infinite.
So not only can they do this, they already do, the massive hypocrisy this involves them in means nothing to them. For after all their ‘saving the planet ‘

MarkW

They aren’t just moving the goal posts, they’ve broken out the camo paint.

David in Michigan:
At September 30, 2013 at 6:30 am you ask

I’m late to this thread but I am hoping someone will see this and respond. Various time periods for the “no warming” trend have been put forth…… 10 year, 15 years, 17 years. Why is there no agreement on the length of the period?? Can someone explain ? Anybody……

I answer:
It is because there are several data sets which attempt to determine global temperature using different methods so they differ, and they each provide a different time from now since when there has been no discernible trend (at 95% confidence) in global temperature.
This cessation of discernible (at 95% confidence) in global temperature change is the halt (often misleadingly called the “pause” or the “hiatus”). The different estimates of global temperature provide different indications of when the halt initiated which are all in the range of 17 years to 22 years.
So, either it is accepted that
(a) the halt to changing global temperature started at least 17 years ago and has yet to end
or
(b) it is not possible to determine global temperature change with useful confidence.
Either possibility indicates there is no valid reason for the scare concerning anthropogenic (i.e. man-made) global warming (AGW)..
Richard

In a guest essay by Barry Brill he said,
. . . .
Few expected that would happen, predicting a sharply-reduced best estimate of sensitivity and rueful acknowledgment that natural factors had been under-estimated. The fact that days of debate culminated in this absurd canard about 30-year trends is a powerful indicator of just how desperate the climate establishment has now become.
[bold emphasis by me- JW]

– – – – – – –
Barry Brill,
Your essay is a source of excellent intellectual ideas. Thanks for your work.
If the bold part of your above quoted paragraph (the last paragraph of your essay) is a conclusion by you, then I do not see how it necessarily follows from your essay.
I offer a different conclusion that perhaps is closer to necessarily following from you excellent essay. I offer as an alternate conclusion the following.

CONCLUSION proposed by JW:
The IPCC Bureau is proclaiming its explicit irrationality, finally, and displaying it as a requirement for exclusive membership in its post-modern based ideology.

John

Louis Hooffstetter

“AR5 cites 0.05°C/decade (warming) without mentioning that this figure is ±0.14°C”…
This illustrates yet again why Climastrologists should never, ever be referred to as scientists. Real scientists understand that measurements that fall within the uncertainty (or variation) of the measuring device are meaningless. “Real Climastrologists” are simply be alarmists with Ph.Ds.

If there is a 56 or 58 or 60 year natural cycle, as some see in the records, then a policy of 30 years would be maximally foolish.

Jimbo

Ian W says:
September 30, 2013 at 4:46 am
…….Do not fool yourselves that by deconstructing the SPM here or in ‘friendly’ media that the politicians or their bureaucracies will stop………….
……Does anyone really think that this will be stopped by saying – but you said previously climate metrics over 10 years was good enough?…….

I agree. They will keep pushing because this thing has become to big to fail, but what else can we do? This is a behemoth that is being chipped away at bit by bit. The consensus if cracking, the media are now asking better questions etc. But I agree that even if we went into 15 years of cooling they would not surrender. A paper would be rushed out to say that 30 years of no temperature increases are not unusual, forgetting our co2 was supposed have driven surface temps higher.
What will stop this, as you say, is voter backlash against high energy bills.

Jimbo

If you are a climate scientist reading this: please think about your future reputations. Dr. Judith Curry will come out of this relatively unscathed as she saw the light just in time.
PS What did Dr. Gavin Schmidt say about the period of time that would elapse for him to reconsider AGW?

herkimer

Kev -in-UK
You said
“lo and behold, we are in a flat/cool period, and fairly likely to cool further. Bingo ! – you have convinced me that AGW is definitely deceased and all the carbon environmental crapola is just that !”
You are right on!
Three major long term climate forcing factors like the sun , the oceans and the Arctic are all pointing to global cooling and are already into their cool cycle mode , so IPCC may very well be toast as Judith Curry so well stated . Looks like it will take some very cold winters to make the rest of the world to see it as well. These cold winters are just around the corner starting in this decade.This may last for the next 20-30 years as they did from 1880-1910 .

James

if indeed the effect of C02 is logarithmic shouldn’t we be about done with any athropogenic contribution to the warming anyway? Clearly natural forces are in control.
http://wattsupwiththat.com/2010/03/08/the-logarithmic-effect-of-carbon-dioxide/

herkimer on September 30, 2013 at 7:37 am

– – – – – – –
herkimer,
If your screen name is associated with your location, then I might be within 50 miles of you.
: )
John

Kev-in-Uk

herkimer says:
September 30, 2013 at 7:37 am
My apologies – I misread your initial post to take it you had an alarmist stance! (at least it seemed that way to me!)

richardscourtney says:
September 30, 2013 at 5:21 am
I have repeatedly said the need now is to mobilise people with real expertise in political activity (e.g. Lords Lawson and Monckton, Senator Inhoffe, ex-President Klaus, etc.).
Mr. Courtney
Peter Lilley is well known moderate sceptic, active member of the UK Parliament, currently on the Energy and Climate Change Committee, hence well position to make an impact on the government climate policy.

Matthew R Marler

This inconsistency in the requirement for long trends, and in particular the short trend before James Hansen’s 1988 Congressional testimony, has been pointed out before at numerous times and places. Have main stream media and popular science publications ever taken note?

vukcevic:
At September 30, 2013 at 9:01 am you say to me

Peter Lilley is well known moderate sceptic, active member of the UK Parliament, currently on the Energy and Climate Change Committee, hence well position to make an impact on the government climate policy.

Yes, and other AGW-sceptic politicians exist in several countries. They need our help, support and encouragement.
Importantly, and as I tried to say, people with political experience need to be mobilised to publicise the truth about the IPCC, its nature, Role and lack of veracity. We have won on the science, and now we need to stop the political agenda for which ‘science’ was always merely a front.
Richard

herkimer

John Whitman
We may be neighbours . I live in Southern Ontario, Burlington.

herkimer

Kev-in UK
I accept your apology. The point that I was trying to make is that one does not have to wait 30 years to see a different developing trend already happening like the last 16 years and take what ever action[ or no action ], if any, as neccessray . In addition the next 30 years may have very little to do with the factors that affected the weather in the past 30 years , so relying only on the trend of a past 30 year period becomes meaningless if the factors causing the trend are changing significantly. It is like predicting fall or winter based on the trend of the summer, it does not work.. With the IPCC forecast , they are trending their 100 year prediction based on trend of a cyclic pattern that was just in the warm mode, yet totalling ignoring that long range factors that cause global cooling have already started with our 16 year pause and the past 30 years is no indication of the future. So what is the sense of waiting for 30 years to get old weather data .

Kev-in-Uk

herkimer says:
September 30, 2013 at 11:11 am
”So what is the sense of waiting for 30 years to get old weather data .”
Oh, that’s easy – it’s because ‘waiting’ for the data enables a sh$tload of extra snaffling at the AGW feeding trough!