What would the IPCC have written if there had been 12 years of rapid warming?

Climatologists now require 20 to 30 years to even consider any climatic trend: Is that really honest, or is it just very convenient?

Guest essay by Stephane Rogeau of France

So that’s it: the 15+ years period of no temperature increase is, according to the IPCC, a non-event, barely worth mentioning in the Summary for Policy Makers (SPM). The explanation is simple: we are just witnessing short usual natural variations of the climate that are consistent with climate models. The question about whether those models had foreseen this so-called “hiatus” is just irrelevant: move along!

But let’s just imagine for a while that since around 2000, the world had seen a warming bigger than everything the IPCC had ever predicted. I mean a situation just opposite to what we have been experiencing until now with regard to model forecasts. What would have been the analysis proposed by the IPCC in its SPM report?

First possible analysis:

“The long-term climate model simulations show a trend in global-mean surface temperature from 1951 to 2012 that agrees with the observed trend (very high confidence). There are, however, differences between simulated and observed trends over periods as short as 10 to 15 years (e.g., 2000 to 2012). Due to natural variability, trends based on short records are very sensitive to the beginning and end dates and do not in general reflect long-term climate trends. As one example, the rate of warming over the past 12 years (2000–2012; 0.23 [+0.13 to +0.33] °C per decade), which begins after the effect of a strong El Niño disappeared, is bigger than the rate calculated since 1951 (1951–2012; 0.12 [0.08 to 0.14] °C per decade).

The observed extra increase in surface warming trend over the period 2000–2012, as compared to the period 1951–2012, is due in roughly equal measure to an increased trend in radiative forcing and a warming contribution from internal variability, which includes a possible redistribution of heat within the ocean.”

Second possible analysis:

“The rapid increase in surface warming during the last period of more than 12 years is a clear sign that, although climate models have gained in precision in their description of climate behavior, several factors had been under-estimated by the scientific community in the AR4. There is strong evidence that both lower and upper limits of the former estimation of transient climate response should be risen by as much as 1°C (very high confidence).

Projections for annual mean surface temperatures for the period 2081-2100 have therefore been reviewed to take into consideration the change in observed trend over the last period of 12 years. All different scenarios now show a very likely increase of global mean surface temperatures of more than 1.5°C by the end of the century, relative to 1985-2005, and up to 6°C in the RCP8.5 scenario.”

Let’s be honest: does anybody believe the IPCC would have chosen to write anything close to the first analysis?

Related: To the IPCC: Forget about “30 years”

0 0 votes
Article Rating

Discover more from Watts Up With That?

Subscribe to get the latest posts sent to your email.

90 Comments
Inline Feedbacks
View all comments
Chip Javert
October 2, 2013 9:10 am

(Repost from today’s WUWT “IPCC flip flop on 2100 temperatures”)
My skepticism has gone all the way to cynicism.
I believe most scientists (97%+, including Michael Mann) know CAGW is puerile hogwash. Venal politicians only care that a critical mass of pathetic-but-willing parties (media outlets, laughably scientifically illiterate citizens) act as true believers, and can be manipulated to cede more political power.
That’s it; that’s all there is to CAGW.
Appeals for scientific integrity by well meaning colleagues (eg: Bob Tisdale, et al) are meaningless; politicians want power for power’s sake and willingly fund ethically challenged scientists who readily produce intellectually corrupt theories and papers. When the general population tires of this particular con-job, politicians will easily throw their pet scientists under the proverbial bus, and move on to the next attention grabber.
This is not a battle for hearts and minds; it’s a battle for money and power.

October 2, 2013 9:13 am

Pippen Kool
October 2, 2013 at 8:21 am
says:
‘“What would the IPCC have written if there had been 12 years of rapid warming?”
It would be interesting to speculate on what would WattsUpWithGlobalWarming have written if there had been 12 years of rapid warming.’
Actually, I think it might be more interesting to speculate on the difference in the results achieved between the IPCC and WUWT in comparison to the differential in taxpayer dollars that the IPCC and WUWT receive.
Care to speculate?

Chip Javert
October 2, 2013 9:19 am

Pippen Kool says:
October 2, 2013 at 8:21 am
It would be interesting to speculate on what would WattsUpWithGlobalWarming have written if there had been 12 years of rapid warming.
===============================================================
Ok, Pippen, here’s my speculation:
Based upon current & previously demonstrated WUWT performance, some very bright minds would begin an intense and intellectually honest search for a falsifiable hypothesis describing the underlying physics. WUWT has never denied warming, just the “CA” component…

rogerknights
October 2, 2013 9:26 am

Wonderfully acute. Representatives of the IPCC should be asked the author’s concluding question at a congressional hearing.

Gail Combs
October 2, 2013 9:37 am

RACookPE1978 says: October 2, 2013 at 8:51 am
…Equally alarming, the 40 year trend of ALL Antarctic Sea Ice measurements (maximum, average, and minimum extents) continues their steady increases since 1979. At today’s rates of increase in southern sea ice extents, Cape Horn could be closed to ship traffic as soon as 8 to 12 years.
>>>>>>>>>>>>>>>>>>>
The question then becomes what happens when Drakes Passage is partially blocked or covered in ice and no longer effected by wind?

Effect of Drake Passage on the global thermohaline circulation
Abstract-
The Ekman divergence around Antarctica raises a large amount of deep water to the ocean’s surface. The regional Ekman transport moves the upwelled deep water northward out of the circumpolar zone. The divergence and northward surface drift combine, in effect, to remove deep water from the interior of the ocean. This wind-driven removal process is facilitated by a unique dynamic constraint operating in the latitude band containing Drake Passage. Through a simple model sensitivity experiment WC show that the upwelling and removal of deep water in the circumpolar belt may be quantitatively related to the formation of new deep water in the northern North Atlantic. These results show that stronger winds in the south can induct more deep water formation in the north and more deep outflow through the South Atlantic. The fact that winds in the southern hemisphere might influence the formation of deep water in the North Atlantic brings into question long-standing notions about the forces that drive the ocean’ thermohaline circulation….

Drake Passage and palaeoclimate

ABSTRACT: The effect of Drake Passage on the Earth’s climate is examined using an idealised coupled model. It is found that the opening of Drake Passage cools the high latitudes of the southern hemisphere by about 3°C and warms the high latitudes of the northern hemisphere by nearly the same amount. This study also attempts to determine whether the width and depth of the Drake Passage channel is likely to be an important factor in the thermal response. A deeper channel is shown to produce more southern cooling but the magnitude of the effect is not large. Channel geometry is relatively unimportant in the model because of a haline response that develops when the channel is first opened up.
Introduction
South America and Australia separated from Antarctica between 20 and 40 million years ago, isolating Antarctica and the South Pole behind a continuous band of ocean water. The palaeoceanographic record shows that this separation led to the accumulation of glacial ice on Antarctica and an abrupt cooling of the ocean’s deep water (Kennett, 1977). Both effects persist to this day. The palaeoceanographic record gives every indication that the isolation of Antarctica was a major step in climate evolution.
Today, the band of open water around Antarctica is most restricted between the tip of South America and the Palmer Peninsula, a feature known as Drake Passage. In one of the earliest scientific papers written about the output of an ocean general circulation model, Gill and Bryan (1971) showed how a gap such as Drake Passage alters the ocean’s meridional circulation and heat transport. With Drake Passage closed, the ocean transports heat southward by moving warm water poleward near the surface. Cooling at the Antarctic margin leads to deep-water formation and the northward flow of cold water at depth. With Drake Passage open, warm upper ocean water from the north is unable to flow into or across the channel because there is no net east–west pressure gradient to balance the effect of the Earth’s rotation. The ocean’s ability to transport heat southward is thereby diminished. Cox (1989), England (1992) and Mikolajewicz et al. (1993) carried out similar experiment…..

Reseach on Drakes Passage today: http://climate.gmu.edu/research/drake.php

…Significance
The experiments address a fundamental question of how the circulation of the ocean works. Since the global overturning circulation is apparently sensitive to wind even in regions where the ocean has eastern and western boundaries, it may be influenced by wind outside the Drake Passage latitudes. However, our results indicate that the unique geometry of the Drake Passage latitudes does make the global circulation – and perhaps the climate of the North Atlantic – especially sensitive to wind there….

October 2, 2013 9:58 am

And what will they write if we see 12 years of rapid cooling from now?

RACookPE1978
Editor
October 2, 2013 10:07 am

Gail Combs says:
October 2, 2013 at 9:42 am
Now how the heck did ‘/www.jpl.nasa.gov/new’ get stuck on my name?

Simple. Because of Obama’s shutdown, the “temporary” new guys at ‘/www.jpl.nsa.gov/new can’t afford a spell-checker. (They are all over at http://www.myunsecuregovernmenthealthrecords.com trying to get more SSN’s and birthdates stolen from the IRS)…

richardscourtney
October 2, 2013 10:09 am

Tom Trevor:
At October 2, 2013 at 9:58 am you ask

And what will they write if we see 12 years of rapid cooling from now?

The AGW-scare will be over by then unless there is a large ENSO peak temperature in the intervening years. So, they will probably write nothing.
Richard

rogerknights
October 2, 2013 10:24 am

Thrasher says:
October 2, 2013 at 8:24 am
Is that a typo in the report that says:
“As one example, the rate of warming over the past 12 years (2000–2012; 0.23 [+0.13 to +0.33] °C per decade), which begins after the effect of a strong El Niño disappeared, is bigger than the rate calculated since 1951 (1951–2012; 0.12 [0.08 to 0.14] °C per decade).”
Not one temperature dataset has anything remotely close to +0.23C per decade since 2000. It is also not bigger than the trend from 1951-2012, it is indeed smaller. (roughly +0.07C per decade versus +0.12C per decade)

“the past 12 years (2000–2012 . . .)” –Huh? 2000 through 2012 is 13 years.
2000 is a poor start-year, because it was a sharp temporary drop-off after the 1998 El Nino jump-up. If it was included, it would be a “cherry pick.”
It would have been better to have chosen the most recent decade, 2003-2012. Or to have used 1990-2012 (23 years), since 1990 was the date of the first AR, and since that would have smoothed out the sharp jumps and dips before and after 2000.
Here’s a link to the IPCC’s (correct) draft chart (but its numbers don’t match up to the ones used in the text quoted–apparently the IPCC has shifted the envelope, as others have pointed out):
http://climateaudit.files.wordpress.com/2013/09/figure-1-4-models-vs-observations-annotated.png?w=560&h=480

October 2, 2013 10:45 am

They are working on it…http://dailycaller.com/2013/10/02/liberal-media-huddles-to-re-hype-global-warming/
I wonder if anyone here lives Lenard the meeting site? Would love to be the fly on the wall.

Fabi
October 2, 2013 10:53 am

Some fifteen year periods are more equal than others…

Thrasher
October 2, 2013 11:07 am


I was more interested in where the +0.23C per decade trend between 2000-2012 came from. That is not supported by the global temperature datasets. The trend during that time is less than one third what that sentence claims it is. It doesn’t matter which dataset is used either.

jorgekafkazar
October 2, 2013 11:10 am

“[Remember, many new readers – and some older ones as well – don’t know all of the abbreviations all of the time. Mod]”
That’s what a glossary* is for.
http://wattsupwiththat.com/resources/glossary/

gopal panicker
October 2, 2013 11:17 am

we have had three years of cooling…get ready for 27 more..

Resourceguy
October 2, 2013 11:32 am

I can’t seem to find the research predicting increased hurricanes and intensity that supported Al Gore years ago and around the time of the hurricane spike year. I guess old predictions and supporting research is selectively erased from the record? I think it was FSU research but maybe not. I think it would be instructive to compile that and other predictions as reference pages by prediction topic.

October 2, 2013 11:38 am

After the felonious re-juggling to keep warming going and their “projections” within observations, I now know that they will also jigger the temperature record to suit. After all, they have been doing it for years and they are the gatherers of data. I have been thinking since the surfacestations.org project, that we are going to have to somehow set up our own temp collecting network safe from sabotage. One way is to select 100 global temp stations and duplicate them at some acceptable distance to keep tabs on the network jiggery pokery. These guys have totally jettisoned any pretense at science so it’s only a tiny step to outright totally invent a temperature series. Maybe individuals who live not far from an official station could look after a monitoring network. Oh dear, I don’t like what I’ve become!

October 2, 2013 11:42 am

15+ years of no temperature increase? That’s if you start with the spike of a century class El Nino. Smoothed HadCRUT3 shows the trend. HadCRUT3 is less-warming than the other major surface indices, and can be seen here:
http://www.metoffice.gov.uk/hadobs/hadcrut3/diagnostics/global/nh+sh/
That shows the hiatus as starting sometime in 2011, and currently having gone on for 12 years. Stating 15, 16 or 17 years seems to be cherrypicking the data to overstate one’s case.

RCon
October 2, 2013 11:56 am

You mean like in the 2007 paper by Rahmstorf et al(http://www.sciencemag.org/content/316/5825/709.abstract) where they stated that the 15-year warming trend up to 2006 (which was double the projections) was stated as being “intrinsic variability within the climate system”.
But who needs realy world examples when we’ve got fictitous and hypotheic responses!
See more here http://tamino.wordpress.com/2013/09/21/double-standard/#more-6775

richardscourtney
October 2, 2013 12:00 pm

Donald L. Klipstein:
Your post at October 2, 2013 at 11:42 am is wrong in many ways. It says in total

15+ years of no temperature increase? That’s if you start with the spike of a century class El Nino. Smoothed HadCRUT3 shows the trend. HadCRUT3 is less-warming than the other major surface indices, and can be seen here:
http://www.metoffice.gov.uk/hadobs/hadcrut3/diagnostics/global/nh+sh/
That shows the hiatus as starting sometime in 2011, and currently having gone on for 12 years. Stating 15, 16 or 17 years seems to be cherrypicking the data to overstate one’s case.

Now (i.e. the present) is the only valid start date when considering how long there has been no discernible change in global temperature. And one then considers back in time from now. Any other date is a cherry-pick.
Smoothing the data is processing it. We are interested in whether the data shows a discernible trend: we are not interested in whether processed data shows anything.
Any model of change could be used but climate science uses linear trends, so that is the appropriate model.
The discernment has to be a trend different from zero at 95% confidence because that is the confidence level used by ‘climate science’.
So, to assess whether there has been discernible global warming recently one needs to take one of the data sets of global temperature time series (e.g. HadCRUTn, GISS, RSS, etc.) and assess past time periods from now to determine the shortest time period which differs from zero with 95% confidence.
All the available time series of global temperature show no discernible global warming or global cooling at 95% confidence for at least 17 years. RSS shows no discernible global warming or global cooling at 95% confidence for 22 years.
Any other statement (except to query the validity of global temperature data compilations) is spin.
Richard

October 2, 2013 12:00 pm

Well, here (SPM p xxiv) is what the IPCC FAR did say in 1990 about the 14 years of warming that had been observed to that date:
“The observed increase could be largely due to natural variability, alternatively this variability and other man-made factors could have offset a still larger man-made greenhouse warming The unequivocal detection of the enhanced greenhouse effect from observations is not likely lor a decade or more, when the committment to future climate change will then be considerably larger than it is today.”
Sounds more like the first.

Frank K.
October 2, 2013 12:06 pm

Tom J says:
October 2, 2013 at 9:13 am
“Actually, I think it might be more interesting to speculate on the difference in the results achieved between the IPCC and WUWT in comparison to the differential in taxpayer dollars that the IPCC and WUWT receive.”
On a related note, it appears that workers at NASA (and along with it GISS) are considered NON-essential employees. If you go to nasa.gov you get the following message:
Due to the lapse in federal government funding, this website is not available.
We sincerely regret this inconvenience.

(maybe some workers were spared…)
On no!! Think of all the climate “science” that’s NOT getting done in the U.S. due to the shutdown! It makes a guy wanna do something drastic, like … ummm … get a vasectomy!
‘No children, happy to go extinct’, tweets weatherman after grim climate-change report made him cry (now he’s considering a vasectomy)’
http://www.dailymail.co.uk/news/article-2436551/A-weatherman-breaks-tears-vows-NEVER-fly-grim-climate-change-report.html

Jimbo
October 2, 2013 12:08 pm

Just a re-cap on what others and myself have noted. It seems that at the time they were confident that over 17 years was sufficient. Now the goalposts are moved and they will be moved as many times as necessary. I predicted this some time back.

Dr. Phil Jones – CRU emails – 7th May, 2009
‘Bottom line: the ‘no upward trend’ has to continue for a total of 15 years before we get worried.’
———————–
Santer et. al. – November 2011
Abstract
Separating signal and noise in atmospheric temperature changes: The importance of timescale
A single decade of observational TLT data is therefore inadequate for identifying a slowly evolving anthropogenic warming signal. Our results show that temperature records of at least 17 years in length are required for identifying human effects on global-mean tropospheric temperature.
http://www.agu.org/pubs/crossref/2011/2011JD016263.shtml
———————–
NOAA – The State Of The Climate –
The simulations rule out (at the 95% level) zero trends for intervals of 15 yr or more, suggesting that an observed absence of warming of this duration is needed to create a discrepancy with the expected present-day warming rate.”
http://www1.ncdc.noaa.gov/pub/data/cmb/bams-sotc/climate-assessment-2008-lo-rez.pdf
———————–
RealClimate – 7 February 2013
Short term (15 years or less) trends in global temperature are not usefully predictable as a function of current forcings. This means you can’t use such short periods to ‘prove’ that global warming has or hasn’t stopped,
http://www.realclimate.org/index.php/archives/2013/02/2012-updates-to-model-observation-comparions/

richardscourtney
October 2, 2013 12:37 pm

Nick Stokes:
re your post at October 2, 2013 at 12:00 pm
Taking your interpretation of the 1990 IPCC SPM as being true, then there has been no progress in ‘climate science’ as reported by the IPCC since 1990. That being so, then I assume you agree the $billions per year that is being wasted on ‘climate science’ should be spent on something which could provide something useful.
So, when can we expect you to start campaigning for the funding of your job to be stopped?
Richard

Stephen Richards
October 2, 2013 12:58 pm

Tom Trevor says:
October 2, 2013 at 9:58 am
And what will they write if we see 12 years of rapid cooling from now?
Now that is something I’m really looking forward too. It could even be funnier than AR5 and Nick Stokes, R gates combined

Robin Hewitt
October 2, 2013 12:59 pm

If it requires 30 years to make a trend then you have to wonder if there was any cause for alarm in the first place.