By Dr. David Whitehouse The GWPF (video follows)
Warming Interruptus
What is the reason for the lack of warming observed at the surface of the Earth since about 1997? Many causes have been proposed, and with increasing frequency, but most only rep- resent partial explanations. There are clearly more putative causes than can possibly be the case.
The pause has given climate science several things. It has provided a reassessment of the importance of natural climatic variability and its relationship to human influences on the climate. It has also shed light on the role of so-called sceptics as well as the successes and failures of climate communication.
Here are the current explanations for what has been called the biggest problem in climate science.
There is no pause
Some argue that the pause does not exist and that the warming trend seen to commence around 1980 has continued linearly with predictable variance around the mean. Of course it is possible to draw a straight line through most sets of data and attempt to justify it. However the length of the pause – 17 years – means that it cannot reasonably be regarded as part of a linear trend since 1980, so this explanation no longer works.¹
Low solar activity
Placing the role of solar activity in recent climate has been problematical. It is obvious that that periods of low solar activity in the past have coincided with cooler climatic conditions. Examples include the Dalton solar minimum around 1800 and the Maunder minimum in the 17th century (now shown to undoubtedly be a global event). Prior to about 1960 solar ac- tivity played a major role in the Earth’s climate, but in recent decades the IPCC has declared that it plays only a minor part, being dwarfed by human influences on the climate. So what is to be made of the recent decline in solar activity from the relatively high levels in the late 20th century? Some believe that the sun is entering a lengthy period of low activity as it has done in the past. Curiously, the commencement of that low activity coincides with the pause in global surface temperature. There are indications that almost all climate models underplay the effect of solar activity. Some have asked how, if the slight increase in total solar irradiance over the past 30 years cannot cause the warming, it can have contributed to the pause. This effect is likely to be relatively short lived. ²
As one paper on the subject put it:
The purpose of this communication is to demonstrate that the reduced rate in the global temperature rise complies with expectations related to the decaying level of solar activ- ity according to the relation published in an earlier analysis Without the reduction in the solar activity-related contributions the global temperatures would have increased steadily from 1980 to present.
The IPCC Fifth Assessment report estimates that despite the decline in solar output since 2000, total warming influences have increased faster since 1998 than over 1951–1998 or 1971–1998.
The heat is in the oceans
The most cited explanation for the pause is that the warming has gone into the oceans, and indeed the oceans are expected to absorb far more energy from the greenhouse effect than the land. But while the oceans have warmed in the past few decades, the extent to which this is due to mankind is debateable and the ocean heat content data is not behaving as some expected.
The best data we have is from the ARGO project. It goes back ten years and shows no warming in the uppermost layers of the oceans, and only modest warming down to 1800 m. If more heat is there it must be at deeper levels, where it is far harder to detect, and where it may well be locked out of the way for a thousand years. ³
Pacific decadal oscillation/Atlantic multidecadal oscillation
The Pacific decadal oscillation (PDO) switches from warm to cool every 30 years or so. It went positive in 1976–98 and has been mostly negative since about 2000. Given the Pacific’s pos- tulated influence on global climate this might indicate that the pause will continue until the PDO changes again, which will be in 15–20 years. A similar effect has also been suggested for the 60–70-year Atlantic multidecadal oscillation. (4)
Stratospheric water vapour
A very interesting paper suggests that natural variations in stratospheric water vapour could be responsible for about a third of the 1980–98 warming phase. Lead author Susan Solomon, of the US National Oceanic and Atmospheric Administration, said:
Current climate models do a remarkable job on water vapour near the surface. But this is different – it’s a thin wedge of the upper atmosphere that packs a wallop from one decade to the next in a way we didn’t expect.
Solomon and her co-authors concluded that decreases in stratospheric water vapor concentrations acted to slow the rate of increase in global surface temperature over 2000–9 by about 25% compared to the warming that would have occurred due only to carbon dioxide and other greenhouse gases.
More limited data suggest that stratospheric water vapour probably increased between 1980 and 2000, which would have enhanced the decadal rate of surface warming during the 1990s by about 30% compared to estimates neglecting this change. (5) However, the IPCC Fifth Assessment report shows very little warming from stratospheric water vapour over 1980– 2000 and no cooling from it over 2000–2010.
Chinese coal
Kaufman et al. (2012) suggest that the increased burning of coal in China is producing aerosols that are cooling the world. Others suggest this conclusion uses computer model data that has been cherrypicked to give the required result. It also does not include the latest solar data. (6,7) Moreover, the IPCC Fifth Assessment report does not support this finding.
The Pacific and the La Niñas
Some scientists suggest that recent cooling in the eastern equatorial Pacific reconciles cli- mate simulations and observations. Although they consider only 8.2% of the global surface they maintain that their computer model reproduces the annual-mean global temperature remarkably well for 1970–2012, a period that includes the current hiatus and a period of ac- celerated global warming. They postulate that the pause is part of natural climate variability, tied to a La-Niña-like decadal cooling. Although similar decadal hiatus events may occur in the future, they say, the multidecadal warming trend is very likely to continue due to man’s influence on the climate. (8)
Stadium waves
In this idea the extent of sea ice in the Eurasian Arctic enhances or dampens the long-term trend in rising temperature. Such changes introduce a low-frequency climate signal, which propagates across the Northern Hemisphere through a network of synchronised climate in- dices. The tempo of its propagation is rationalised in terms of the multidecadal component of Atlantic Ocean variability – the Atlantic multidecadal oscillation. The authors of the stadium wave paper say, ‘the Eurasian Arctic Shelf-Sea Region, where sea ice is uniquely exposed to open ocean in the Northern Hemisphere, emerges as a strong contender for generating and sustaining propagation of the hemispheric signal’. This explanation suggests that the pause should end in the 2030s. (9)
Arctic stations
Could it be that the pause is an artefact of poor spatial sampling? This is the suggestion from Cowtan and Way (2013). They compare different ways of accounting for the lack of weather- station data in various regions of the globe, principally the Arctic. They maintain that when the data are infilled the pause goes away and that the warming rate is similar to that seen in the 1990s.
The problem with this approach is that it involves creating a hybrid dataset using different infilling techniques for different regions, leaving it open to suggestions of cherrypicking. (10,11)
Pacific trade winds
According to some scientists a key component of the pause has been identified as the cool eastern-Pacific sea-surface temperature, even though it is not clear how this ocean has re- mained cool despite the long-term warming effect on the climate due to human activity. It is contended that there has been a strengthening in Pacific trade winds over the past two decades that has not been factored into climate models and that when these changes are made the effect is sufficient to account for the cooling of the tropical Pacific and a substan- tial slowdown in surface warming through increased subsurface ocean heat uptake. The sci- entists who suggest this have used model-based ocean temperature ‘reanalyses’, not mea- surements, and the mechanism involved implies the heat uptake in the top few hundred metres of the ocean should have increased during the pause, but measurements suggest otherwise. (12)
Note also that a few years ago other scientists were suggesting the opposite: that weak trade winds were responsible for the pause. (13)
Volcanoes
Since Mt Pinatubo in 1991 there have been no volcanic eruptions sufficiently large to obvi- ously reduce global temperatures. However, it has been argued that there has been a num- ber of smaller eruptions, the cumulative effect of which might partly account for the pause. This is the argument of Santer et al. (2014). However, these authors estimate this is likely to have caused only a 15% reduction in the temperature trend since 1998, only a fraction of the actual reduction. (14,15)
A coincidence!
It has been suggested that the computer climate predictions are running too warm because they are not properly accounting for volcanic aerosols, aerosols in general, solar activity and the effects of El Niños. In a recent Nature commentary, Schmidt et al. suggest that, taking these climatic influences together, they can completely explain the pause. The problem with this approach is that other influences are ignored and a non-unique combination of factors has been cherrypicked to provide the explanation. (16)
Notes
1 http://www.lse.ac.uk/GranthamInstitute/Media/Commentary/2012/october/myth-that-global-warming-stopped-in-mid-1990s.aspx
2 http://www.scirp.org/journal/PaperInformation.aspx?PaperID=41752
3 http://onlinelibrary.wiley.com/store/10.1002/2013EF000165/asset/eft24.pdf
4 http://www.pnas.org/content/110/6/2058.full.pdf
5 http://www.thegwpf.org/water-vapour-and-the-recent-global-temperature-hiatus/
6 http://wattsupwiththat.files.wordpress.com/2011/07/pnas-201102467.pdf
7 http://www.cawcr.gov.au/staff/jma/Decadal.trends.Meehl.JClim.2013.pdf
8 http://www.nature.com/nature/journal/vaop/ncurrent/full/nature12534.html
9 http://judithcurry.com/2013/10/10/the-stadium-wave/
10 http://www.thegwpf.org/pause/. 11http://onlinelibrary.wiley.com/doi/10.1002/qj.2297/abstract. 12http://www.thegwpf.org/pacific-pause/
13 http://www.nature.com/nature/journal/v441/n7089/abs/nature04744.html
14 http://www.thegwpf.org/volcanoes-20-year-pause/
15 http://www.nature.com/ngeo/journal/v7/n3/full/ngeo2098.html.
16 http://www.nature.com/ngeo/journal/v7/n3/full/ngeo2105.html
they have to make it global not local. Like they prefer global sea levels rather than regional because it hides the fact some have falling sea levels which means other processes are at work other than the co2 deathstar dogma. By making averages global they can ‘hide declines’. Which for me explains the recent thread on real climate looking looking for methods to make a global temps chart to blow away what they call the ‘misinformation’ on temps.
global means explanations do not have to be given for the regional differences. co2 must warm the whole earth not just one bit of it. Can’t sell co2 without making everything global averages.
Until a little child says, “ICPP”?
There is no Climate Science.
At best, there are scientists working on developing same.
Proving Anthropogenic influence is still very problematic.
You guys just gotta cut the team some slack.
For Pete’s sake – remember this is all settled science. It’s not like some big mystery…
As soon as the boys get finished with various libel suits, censoring colleagues, corrupting the peer review process, burning original climate records, revising their data (yet again), refusing debate invitations, studying tree rings, and saving the polar bear, they will tell us what the “settled science” answer is.
Do I REALLY need /sarc?
Remember a while back when Trenberth claimed the Null Hypothesis should be CAGW? We all poo pooed that, but right under our noses they have done just that.
The question of what is causing “the pause” or for that matter the existence of something called “the pause” presupposes truth of CAGW. It has become the Null Hypothesis. With that out of the way, now they have to develop hypothesis for why nothing is happening. Assuming CAGW is the Null Hypothesis is the only reason they cannot look for an answer in the only place it will be found.
Let’s put the Null Hypothesis back where it belongs. CAGW has never been proven. The Null Hypothesis is natural variation. There is nothing to explain, no reason to look for some cause for nothing happening.
Actually JohnM did hit the nail on the head. And while Dr. Whitehouse gets to it at the end, most of his short spiel is spent talking about what we already know.
But it is what we do not know that is most intriguing. And the reason the models are wrong. If you are looking around the corner for the money you dropped, you will never find it.
gbaikie says, March 26, 2014 at 2:51 pm:
“Ocean certainly absorb more sunlight than land.
But I don’t see how oceans absorb more energy from greenhouse effect, as the ocean is transparent to sunlight and is not transparent to IR of greenhouse gases.
So more 90% of energy of sunlight warms beneath the surface of the ocean, whereas no IR reaches below the surface of the ocean.
It seems sunlight has most effect upon temperature of ocean and greenhouse effect has least effect upon ocean.”
That’s the eternal mistake being done, treating the atmosphere as a second provider of energy to the surface, as if it adds an extra INput.
In the real world, the warm body (the ocean) receives no energy from the cold body (the atmosphere) at all. It delivers energy to it.
Radiation (EM waves) is of course being emitted in all directions, but the FLOW OF ENERGY between two bodies at different temperatures (not to say the least, where the one body actually heats the other one), ALWAYS and ONLY goes one way, from hot to cold.
This seems to be a very hard concept for people to grasp. Much easier then to naively imagine two opposite and distinctly separated ‘highways’ set up between the two bodies where energy in the form of ‘light particles’ is transported back and forth.
No, simply compare it with an electrical current or a flow of air (wind) between a high pressure and low pressure. It’s all about gradients/differences in POTENTIAL.
Individual electrons surely fly around in all directions, but the CURRENT moves only one way. Driven by the voltage across the circuit. Likewise, individual air molecules surely fly around in all directions, but the FLOW of air, the wind, moves only one way. From high to low pressure.
The size of the difference in potential, the gradient between high and low, whether it’s represented by voltage or pressure … or temperature, determines the strength of the flow (resistance disregarded).
You cannot accuse those on the ‘right’ side of the argument of cherry picking, only us ‘deniers’ cherry pick don’t you know?
Scientists, meteorologists, etc have known about the Pacific decadal oscillation/Atlantic multidecadal oscillation for more than a century and is common knowledge among meteorologists.
Why then – did our esteemed climate scientists – who are obviously smarter that the rest of us – not factor this into the models.
I’ve been an operational meteorologist for 32 years. These decadal oscillations were not common knowledge and used for widespread forecasting for nearly as long as you stated. I’ll guess that maybe the last 2 decades.
They were not taught at university’s up to the early 1980’s, which is when I graduated.
I strongly believe that one of the biggest problem with climate scientists and global climate models is explained by humans having a confirmation bias.
With regards to meteorologists, we live and die by the models. We use them for guidance. At the start of most careers, many of us gain a false sense of security and confidence in our forecast because we can interpret model data and weather charts so well.
It’s just a matter of time and busted forecasts, after we were correct interpreting the model projections but wrong about the weather to learn the lesson about models that climate scientists can’t learn as easily.
The reason has to do with the number of forecasts and time frame to judge skill.
A meteorologist makes a new forecast every day based on model guidance. Some time frames are longer of course but at the end of their first year, they’ve had at least 100 opportunities to see the models perform and bust numerous times.
This provides a reality check on the skill level of models to predict and the meteorologists limitations to forecast using this tool.
Take a climate scientist or global climate model going out 50 years. Let’s say Michael Mann made his first climate forecast, using global climate models in 1990, when he was 30 years old(just a guess on the numbers). He will be 80, in the year 2040 when the period that forecast covered is over.
Obviously, there “should” be numerous opportunities with time, to adjust the forecast based on new information(just like a meteorologist may update a day 7 forecast, each day as it gets closer). However, the point is clear that climate scientists, convinced that they have(had) it right and with 30 more years(of a 50 year forecast for instance) left for instance and without using climate models enough times to experience the daily reality model check of a meteorologist, they take a loooooooooong time to learn the lesson about having complete faith in models.
I realize that the mathematical equations representing the physics are much different in global weather models vs global climate models and these are 2 different animals in forecasting but if this were the year 2,100, with global climate models in use for over 100 years and not any better than the ones we have been using the last 2 decades, no question that climate scientists would be capable of much greater objectivity using empirical data to guide them towards proper adjustments vs confirmation bias because they are married to their forecast that is busting badly.
evanmjones says:
March 26, 2014 at 3:08 pm
My prior comment – Scientists, meteorologists, etc have known about the Pacific decadal oscillation/Atlantic multidecadal oscillation for more than a century and is common knowledge among meteorologists.
Evan’s response – Some oscillations were known earlier than others. NAO, for example. But the PDO, the biggie, was not recognized (except by fishermen) until the late 1990s. That’s how a lot of the fundamental errors in climate science have occurred, such as the exaggeration of aerosol effect from 1950 to 1975.
Evan – I think we agree on the broader point – which is that the climate scientists, who know so much more than us mere peons, ignored a lot of science
O H Dahlsveen, that wasn’t what I had in mind. The problem I see is how the modelers think, not necessarily what’s in their models. I’ve had a fair bit of personal experience over the last year. They don’t think like scientists.
27 March: Age: Peter Hannam: IPCC dispute simmers over economic costs of climate change
Richard Tol, a lead convening author of the chapter 10 in the upcoming Intergovernmental Panel on Climate Change’s report due for release at the end of March, said he disagreed with the general findings that global warming will bring major disruptions to nations and nature.
“I think the [Summary for Policymakers] drifted too far to the alarmist side,” Professor Tol told Fairfax Media in an email…
Bob Ward, an expert reviewer of the chapter, complained to the IPCC that the additions, including clause 10.9.2., downplayed the economic costs of climate change and also contained errors. He also rejected comments by Professor Tol and co-chair of the entire Working Group II report Chris Field, that his complaints had been accepted outside the normal review process.
“There was no way within the IPCC’s official review processes for me or any other expert reviewer to see the final draft which was distributed to governments,” Mr Ward told Fairfax. “It is only because I bothered to download from a blog a leaked copy of the final draft of chapter 10 that I was able to see the changes and spot the errors.”
The spat sheds light on the relative paucity of economic research on climate change and also the difficultly of capturing the costs of extreme weather events or calamities such as conflict over food or water…
Andy Pittman, director of the University of NSW’s Centre of Excellence for Climate System Science, said that while climate science “is scaffolded on phenomenally sound foundations”, economists dealt with competing assumptions of human behaviour .
Economics “does not have the luxury of those projections being anchored in something that is immutable like the laws of physics”, Professor Pittman said…
http://www.theage.com.au/environment/climate-change/ipcc-dispute-simmers-over-economic-costs-of-climate-change-20140327-35jho.html
Lorenz’s Butterfly has gotten loose again!
Economic costs of climate change?
How convenient to use an unproven theory for high end speculation about economic costs of climate change that have yet to occur and underestimate the massive gains from the irrefutable law of photosynthesis that are known to be occurring with absolute certainty.
http://www.co2science.org/education/reports/co2benefits/MonetaryBenefitsofRisingCO2onGlobalFoodProduction.pdf
What controls weather? The sun, galactic particles that can be deflected by solar activity, so less clouds, severe volcanic eruptions, jet streams, and seasonal changes. Well a huge meteorite or asteroid could too. Solar storms? Now why would human kind have a hand in? Only in cities that create their own micro-climates and UHI that also create pollution. It has been long known that water vapor is the largest greenhouse gas, and we can’t control that either. I have long thought that governments and these gravy train opportunists, have realised that a new ice age would affect human activities in the Northern Hemisphere. When they started a new ice age scare in the seventies, they were silenced and told to forget that! Even the late Carl Sagan suggested that human activities created a warmer earth and this could herald a new ice age. It is true that the earth has gone in climatic cycles, and warming preceded a colder period, but nothing to do with humans.
@ur momisugly Pat Frank: Because they are not scientists, by any convoluted definition.
@ur momisugly Mike Maguire: Not to mention the quantifiable suffering from food & energy poverty- epitomized by the tens of thousands of seniors in the UK perishing every winter.
In the world of finance, where non-disclosure of material facts jeopardizes one’s freedom, much less their job, most of these guys would be long gone.
I find it surreal. It’s as though Madoff’s schemes were revealed in documents leaked to the public and most others in the world of finance remained silent as Bernie continued to publicly brag about the validation of his models returning 15% annually. Further, the brave few that challenged the Madoff models were sued by Bernie for defamation.
The striking differences- Bernie, primarily targeting the wealthy, could only dream of the sums CAGW is sucking from those that can least afford it.
Jimbo says:
March 26, 2014 at 2:05 pm
Did the oceans eat the 1910 to 1940 warming? Long live the pause.
======================================================
I hope not. Warmer is better!!!!!!!!!!!!!!!!
Excuse 13.
Racist Magic gas.
Based on the data, CO2 of an Asian Ethnicity must cause global cooling.
While nasty capitalist CO2 causes global warming.
We have evidence..when western emissions dominated there was global warming, as Asian emissions have matched and then overpowered the efforts of the west, there has been stagnation and an indication of global cooling.
This is the only “logical” explanation.(Using UN IPCC logic ™)
All consensus loving climatologists Know that all climate is driven by the Magic Gas and only mans CO2 emissions have this magical potential, therefor the above is the only explanation.
Please send Nobble piece prize and cash, small unmarked bills.
kenw It is simple the models cannot be fixed. You cannot model chaos, chaos is weather and climate. you may be able to fit a curve for a while but in the long rung you model will eventually run off the rails big time. Believing you can ‘fix the models” comes under the category of “you cannot fix stupid”. Models will work with some degree of accuracy for a short period of time(hour to days) anything beyond seven days is doomed for failure. It the nature of chaos and you cannot “fix” chaos.
To all I erred I said “Believing you can ‘fix the models” comes under the category of “you cannot fix stupid”.” I meant to say Believing you can ‘fix the models” comes under the category of “you can fix stupid”. hope it clear up what I meant thanks and good luck to all.
Relative to the “Biggest Probllem in Climate Science”, here is my “entry” (from a Layman):
The claim is made that the pause cannot be related to aerosols since satellite measurements have shown essentially no change in the level of aerosols for many years.
Also, if aerosolls are involved, there should be cooling because of the massive pollution from the East, but that has not happened.
However, the cause of the pause actually IS due to aerosols.
According to the EPA, between year 2000 and 2012, annual emissions of SO2 due to the Clean Air Acts were reduced by 10 Megtons, with more occurring overseas. (The total of all pollutant emission reductions, in the US alone, is reported as 54 Megatons).
These figures represent the reduction in the atmospheric loading of aerosols, which will naturally increase surface warming due to greater insolation (as happens after the pollution from a large volcanic eruption settles out of the air). But, again, this has not happened.
The reason is simply that the expected warming due to aerosol reductions in the West is being offset by the aerosol emissions from the East. Because of this offsetting, satellite measurements will show little change in aerosol amounts. This offsetting is shown in the graph of “Global Anthropogenic SO2 Emissions”, (Smith, et al, 2011), beginning somewhat before year 2000.
It is unlikely that this offsetting can continue indefinitely. If the East cleans up its air, the expectation would be that warming would resume. However, the warming would be far from catasthrophic, with no concerns about runaway warming.
Solar irradiance has been decreasing since 1980, which could cause some cooling of the earth. An increase in warming, therefore, could actually be beneficial (and potentially be used as a “control knob” for the climate, if too much cooling occurs)
Comments?
The pause is due to the gradual waning effect of high solar activity in the 20th century combined with a negative PDO. It’s plain obvious. C02 is trying to counter it but can’t manage, showing climate sensitivity to co2 is low.
The whole argument that most late 20th century warming is due to humans is wrong, because they never took into account the delayed (multi-decadal) effect that high solar activity would have on the climate, (much the same as a delayed peak in summer warmth after the summer solstice, and a delay of several hours in daily temperatures after noon), combined with a positive PDO at the time. They are now gradually realising their mistake.
The next few decades will show just how much climate is (weakly) sensitive to c02, expect the next few decades to remain static or even decline as the negative PDO and weak sun over-ride the weak warming effect from c02 and other greenhouse gases.
The sad thing is the climate scientists have said that the global warming could not be explained by natural variation- however most excuses for the “pause” show natural variation can explain said “pause” .
‘Andy Pittman, director of the University of NSW’s Centre of Excellence for Climate System Science, said that while climate science “is scaffolded on phenomenally sound foundations” ‘- Chris Turney’s Centre; how sad.
“In a recent Nature commentary, Schmidt et al. suggest that, taking these climatic influences together, they can completely explain the pause.”
—
On the other hand, by taking climatic influences together, they might completely explain the warming from 1976–98. You can’t make the claim that natural influences can prevent warming over an extended period without also acknowledging the possibility that they can cause warming over a similar time frame.
“john robertson says:
March 26, 2014 at 8:33 pm
Please send Nobble piece prize and cash, small unmarked bills.”
That’s funny (For me anyway) because this is exactly what the alarmists are trying to do, to “nobble” industry, energy and lifestyles with limits on CO2 emissions.