From ETH Zurich –Why global warming is taking a break
The average temperature on Earth has barely risen over the past 16 years. ETH researchers have now found out why. And they believe that global warming is likely to continue again soon.
Global warming is currently taking a break: whereas global temperatures rose drastically into the late 1990s, the global average temperature has risen only slightly since 1998 – surprising, considering scientific climate models predicted considerable warming due to rising greenhouse gas emissions.
Climate sceptics used this apparent contradiction to question climate change per se – or at least the harm potential caused by greenhouse gases – as well as the validity of the climate models. Meanwhile, the majority of climate researchers continued to emphasise that the short-term ‘warming hiatus’ could largely be explained on the basis of current scientific understanding and did not contradict longer term warming.
Researchers have been looking into the possible causes of the warming hiatus over the past few years. For the first time, Reto Knutti, Professor of Climate Physics at ETH Zurich, has systematically examined all current hypotheses together with a colleague. In a study published in the latest issue of the journal Nature Geoscience, the researchers conclude that two important factors are equally responsible for the hiatus.
El Niño warmed the Earth
One of the important reasons is natural climate fluctuations, of which the weather phenomena El Niño and La Niña in the Pacific are the most important and well known. “1998 was a strong El Niño year, which is why it was so warm that year,” says Knutti. In contrast, the counter-phenomenon La Niña has made the past few years cooler than they would otherwise have been.
Although climate models generally take such fluctuations into account, it is impossible to predict the year in which these phenomena will emerge, says the climate physicist. To clarify, he uses the stock market as an analogy: “When pension funds invest the pension capital in shares, they expect to generate a profit in the long term.” At the same time, they are aware that their investments are exposed to price fluctuations and that performance can also be negative in the short term. However, what finance specialists and climate scientists and their models are not able to predict is when exactly a short-term economic downturn or a La Niña year will occur.
Longer solar cycles
According to the study, the second important reason for the warming hiatus is that solar irradiance has been weaker than predicted in the past few years. This is because the identified fluctuations in the intensity of solar irradiance are unusual at present: whereas the so-called sunspot cycles each lasted eleven years in the past, for unknown reasons the last period of weak solar irradiance lasted 13 years. Furthermore, several volcanic eruptions, such as Eyjafjallajökull in Iceland in 2010, have increased the concentration of floating particles (aerosol) in the atmosphere, which has further weakened the solar irradiance arriving at the Earth’s surface.
The scientists drew their conclusions from corrective calculations of climate models. In all climate simulations, they looked for periods in which the El Niño/La Niña patterns corresponded to the measured data from the years 1997 to 2012. With a combination of over 20 periods found, they were able to arrive at a realistic estimate of the influence of El Niño and La Niña. They also retroactively applied in the model calculations the actual measured values for solar activity and aerosol concentration in the Earth’s atmosphere. Model calculations corrected in this way match the measured temperature data much more closely.
Incomplete measured data
The discrepancy between the climate models and measured data over the past 16 years cannot solely be attributed to the fact that these models predict too much warming, says Knutti. The interpretation of the official measured data should also be critically scrutinised. According to Knutti, measured data is likely to be too low, since the global average temperature is only estimated using values obtained from weather stations on the ground, and these do not exist everywhere on Earth. From satellite data, for example, scientists know that the Arctic region in particular has become warmer over the past years, but because there are no weather stations in that area, there are measurements that show strong upward fluctuations. As a result, the specified average temperature is too low.
Last year, British and Canadian researchers proposed an alternative temperature curve with higher values, in which they incorporated estimated temperatures from satellite data for regions with no weather stations. If the model data is corrected downwards, as suggested by the ETH researchers, and the measurement data is corrected upwards, as suggested by the British and Canadian researchers, then the model and actual observations are very similar.
Warming to recommence
Despite the warming hiatus, Knutti is convinced there is no reason to doubt either the existing calculations for the climate activity of greenhouse gases or the latest climate models. “Short-term climate fluctuations can easily be explained. They do not alter the fact that the climate will become considerably warmer in the long term as a result of greenhouse gas emissions,” says Knutti. He believes that global warming will recommence as soon as solar activity, aerosol concentrations in the atmosphere and weather phenomena such as El Niño naturally start returning to the values of previous decades.
Literature reference
Huber M, Knutti R: Natural variability, radiative forcing and climate response in the recent hiatus reconciled. Nature Geoscience, online publication 17 August 2014, doi: 10.1038/ngeo2228
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So the final solution is to ‘correct’ projected temperatures downwards and ‘correct’ measured temperatures upwards and declare the science settled.
Why am I not [surprised],
“……..If the model data is corrected downwards, as suggested by the ETH researchers, and the measurement data is corrected upwards, as suggested by the British and Canadian researchers, then the model and actual observations are very similar……
did I really read that!! Gawd Alive.
So when it’s not warming, the reasons are natural (and incomplete data), but when it’s warming, the reasons are man made (and the data is good)?
The warming will not be commencing going forward. To the contrary the cooling will be accelerating going forward.
How can El Niño warm the earth? Any energy released from an El Niño event is energy that is already here, not new energy trapped by hellish republican sweat shops churning out SUV’s by the billions. Like moving cash from one pocket to the other has no affect on your wealth, moving energy from one place to another in the Earth system does not change the energy balance between the planet and the universe.
SOLAR CLIMATE MECHANISMS AND CLIMATE PREDICTION
MECHANISM ONE
One solar climate mechanism/connection theory which has much merit in my opinion, is as follows:
A BRIEF OVERVIEW. At times of low solar irradiance the amounts of sea ice in the Nordic Sea increase, this ice is then driven south due to the atmospheric circulation (also due to weak solar conditions) creating a more northerly air flow in this area.(-NAO) This sea ice then melts in the Sub Polar Atlantic, releasing fresh water into the sub- polar Atlantic waters, which in turn impedes the formation of NADW, which slows down the thermohaline circulation causing warm air not to be brought up from the lower latitudes as far north as previous while in lessening amounts.
This perhaps can be one of the contributing solar/climate connection factors which brought about previous abrupt N.H. cool downs during the past.
This makes much sense to me.
NAO= NORTH ATLANTIC OSCILLATION
NADW= NORTH ATLANTIC DEEP WATER
To elaborate on the above, when the sun enters a prolonged solar minimum condition an overall reduction takes place in solar spectral irradiance, namely in UV light (wavelengths less then 400 nm). The shorter the wavelength, the MUCH greater the reduction.
UV light reduction likely will cause ocean heat content and ocean surface temperatures to drop, due to the fact that UV light in the range of 280 nm-400nm penetrates the ocean surface to depths of 50-100 meters. A reduction in UV (ultra violet) light then should have a profound effect on the amount of energy entering the ocean surface waters from the sun extending down to 50-100 meters in depth, resulting in cooler ocean temperatures.
This ties into what was said in the above in that if ocean waters in high latitudes such as the Nordic Sea, were to be subject to cooling the result would be much more sea ice which could impede the strength of the thermohaline circulation promoting substantial N.H. cooling.
Adding to this theory is fairly strong evidence that a decrease in UV light will result in a more meridional atmospheric circulation (which should cause more clouds, precipitation and snow cover for the N.H.), due to changes in ozone distribution in a vertical/horizontal sense which would cause the temperature contrast between the polar areas of the stratosphere and lower latitude areas of the stratosphere to lesson, during prolonged solar minimum periods. Ultra Violet light being likely the most significant solar factor affecting ozone concentrations ,although not the only solar factor.
This could then set up a more -NAO, (high pressure over Greenland) which would promote a more Northerly flow of air over the Nordic Sea, bringing the sea ice there further South.
MECHANISM TWO
A reduction of the solar wind during a prolonged solar minimum event would cause more galactic cosmic rays to enter the earth’s atmosphere which would promote more aerosol formation thus more cloud nucleation. The result more clouds higher albedo, cooler temperatures.
Compounding this would be a weaker geo magnetic field which would allow more galactic cosmic ray penetration into the atmosphere , while perhaps causing excursions of the geo magnetic poles to occur in that they would be in more southern latitudes concentrating incoming galactic cosmic rays in these southern latitudes where more moisture would be available for the cosmic rays to work with, making for greater efficiency in the creation of clouds.
MECHANISM THREE
MILANKOVITCH CYCLES overall favor N.H. cooling and an increase in snow cover over N.H high latitudes during the N.H summers due to the fact that perihelion occurs during the N.H. winter (highly favorable for increase summer snow cover), obliquity is 23.44 degrees which is at least neutral for an increase summer N.H. snow cover, while eccentricity of the earth’s orbit is currently at 0.0167 which is still circular enough to favor reduced summertime solar insolation in the N.H. and thus promote more snow cover.
In addition the present geographical arrangements of the oceans versus continents is very favorable for glaciation.
MECHANISM FOUR
High latitude major volcanic eruptions correlate to prolonged solar minimum periods which translates to stratospheric warming due to an increase in SO2 particles while promoting more lower troposphere cooling.
One theory of many behind the solar/volcanic connection is that MUONS, a by product of galactic cosmic rays can affect the calderas of certain volcanoes by changing the chemical composition of the matter within the silica rich magma creating aerosols which increase pressure in the magma chamber and hence lead to an explosive eruption.
Muon densities increase more in higher latitudes at times of weak solar magnetic activity, which is why volcanic activity in the higher latitudes will be affected more by this process.
These four mechanisms make a strong case for a solar /climate connection in my opinion, and if the prolonged solar minimum meets the criteria I have mentioned going forward and the duration is long enough I expect global cooling to be quite substantial going forward.
THE CRITERIA
Solar Flux avg. sub 90
Solar Wind avg. sub 350 km/sec
AP index avg. sub 5.0
Cosmic ray counts north of 6500 counts per minute
Total Solar Irradiance off .15% or more
EUV light average 0-105 nm sub 100 units (or off 100% or more) and longer UV light emissions around 300 nm off by several percent.
IMF around 4.0 nt or lower.
The above solar parameter averages following several years of sub solar activity in general which commenced in year 2005..
IF , these average solar parameters are the rule going forward for the remainder of this decade expect global average temperatures to fall by -.5C, with the largest global temperature declines occurring over the high latitudes of N.H. land areas.
The decline in temperatures should begin to take place within six months after the ending of the maximum of solar cycle 24.
NOTE 1- What mainstream science is missing in my opinion is two fold, in that solar variability is greater than thought, and that the climate system of the earth is more sensitive to that solar variability.
NOTE 2- LATEST RESEARCH SUGGEST THE FOLLOWING:
A. Ozone concentrations in the lower and middle stratosphere are in phase with the solar cycle, while in anti phase with the solar cycle in the upper stratosphere.
B. Certain bands of UV light are more important to ozone production then others.
C. UV light bands are in phase with the solar cycle with much more variability, in contrast to visible light and near infrared (NIR) bands which are in anti phase with the solar cycle with much LESS variability.
So it has not warmed because solar irradiance has been weak for the past 16 years. Does that not prove that it is the sun and not C02 that warms the planet? They expect global warming to resume? How? Solar irradiance is now in decline for at least another 20 years.
‘He believes that global warming will recommence as soon as solar activity, aerosol concentrations in the atmosphere and weather phenomena such as El Niño naturally start returning to the values of previous decades.’
Why should they?
The ground station data sets are actually too warm, not too cool, for a number of reasons. The algorithms to adjust for the urban heat island effect make these stations warmer, not cooler as they should be. Then the ocean data are heated up to agree with the artificially warmer land stations. On top of which, older data are systematically made cooler, since there is a limit to how much Hadley and GISS can adjust current readings upwards, with the satellites watching.
I wonder if they’d put their own money into a Pension Fund that changed their forecast models downwards, and tinkered with share prices to raise them upwards?
If the real numbers don’t fit the ones generated by the model, then clearly the real numbers need to be “corrected” to make them fit . After all, the model cannot be wrong can it? (And these people call themselves “scientists”?) Heck, I suppose the concept of fraud has been removed from their brains?
This is the vegetable soup explanation for the pause – put everything in there, and hope it tastes real good.
If the model data is corrected downwards, as suggested by the ETH researchers, and the measurement data is corrected upwards…
you can produce the result of your choice.
Very neat but science it is not!
Still: eleven signs we are going to a new little ice age.
http://lenbilen.com/2014/07/01/eleven-signs-of-cooling-a-new-little-ice-age-coming/
As you say the records now show temperatures rose rapidly in the 80s and 90s, but in 1999 the temperature data for the US did not show a rapid rise in the 80s and 90s, it was slight rise during the 80s and a drop in the 90s, with the 1930s being the hottest decade for the US in the 20th century. The rapid rise in the 80s and 90s in the US now shows after the temperature data was adjusted. So it surprises me that people just look at that adjusted data and repeat it, quote it, and believe it as if it is obvious. Many of us lived through the 80s and 90s here in the US, there was no talk in the news or by weathermen that the temperature was rising rapidly in those decades, I never felt like it was getting hotter, I never heard anyone make any comment even suggesting they noticed the slightest rise in temperature was happening, we talked about the weather all the time, watched weather reports and listened to weathermen all the time and no one I heard ever, in all those 20 years, ever noticed or suggested anything about it getting hotter. We lived through the hockey stick, supposedly the greatest rise temperature in 1000 years or more, and no one noticed a thing. I feel like we’ve all been brainwashed after the fact into believe something happened that never did happen.
Keith Willshaw said:
August 19, 2014 at 8:31 am
So the final solution is to ‘correct’ projected temperatures downwards and ‘correct’ measured temperatures upwards and declare the science settled.
Why am I not [surprised]
————
Yeah it’s kinda like Holder ordering a third autopsy for that guy in Ferguson. They know the outcome they want, they just have to pummel those pesky facts into submission.
Beat to fit, paint to match.
So they’re using natural variation to prop-up man-made warming theory!
Cooling is always natural variation. Warming is always man-made.
Got it.
Lets just say for a moment he is right. What happens should the sun go into a maunder minimum and we get a volcano or two? Tens of millions died in the depths of the Little ice age due to crop failures. If greenhouse gasses keep the climate warmer for a hundred years than the LIA, then what the heck is wrong with that?
So they invested in Enron and the warmists in Mann’s tree!
“When pension funds invest the pension capital in shares, they expect to generate a profit in the long term.” At the same time, they are aware that their investments are exposed to price fluctuations and that performance can also be negative in the short term. However, what finance specialists and climate scientists and their models are not able to predict is when exactly a short-term economic downturn or a La Niña year will occur.”
This has to be the best essay of Post Normal Science yet.
A textbook explanation of how to not study nature.
Let me see, the claimed events did not occur.
Actual measurements show a failure of these speculations.
But if we just blame everything we previously discounted, then tweak our projections down.Adjust the measured value up..
Climatology will likely never have credibility with taxpayers.
That there is no Catastrophe imminent, makes the conversation pointless.
Even the Alarmed Ones and their lab coated shills now acknowledge this.
The only question left.
Who pays for this shameful episode of mass hysteria?
The cost has been huge.
We taxpayers have been stuck with this bill so far, but now the cause is exposed, these costs must be passed back to the fools and bandits.
I willingly pay for work done to my benefit, however this expenditure and social destruction does not meet any practical test.
dp:
At August 19, 2014 at 8:36 am you say
Sorry, but it does, and global average surface temperature (GASTA) adjusts to re-establish the energy balance between the planet and the universe. Indeed, such redistribution of heat by ocean currents is a more likely explanation of 20th century global warming than changes to atmospheric greenhouse gas concentrations.
The reason is that heat is lost from the planet by radiation, and the radiated flux is proportional to the fourth power of the temperature (T) of the radiating surface. Move heat from a hot region to a cold region such that a change to T/m^2 has the same magnitude (but opposite sign) in each region and then T^4/m^2 is not the same in each region.
Richard
“Climate sceptics used this apparent contradiction to question climate change per se – or at least the harm potential caused by greenhouse gases – as well as the validity of the climate models.”
Why wouldn’t all scientists question this “apparent contradiction”? Oh wait, just read further. Apparently it’s the data (again) that is at fault: “The interpretation of the official measured data should also be critically scrutinised. According to Knutti, measured data is likely to be too low…”
This article is classic. I think cognitive dissonance is firmly settling in.
Lets just say for a moment he is right (alternative version).
I guess he would acknowledge that the catatrophic warming projected in the 80’s and 90’s was clearly overestimated by a factor or 2 or so, and thus the warming limit for the 21st century, of approx. 2C, that we’ve been told we must not breach, looks in fact unlikely to be breached.
So that’s all good then.
Oops!
I intended
and then the change to T^4/m^2 is not the same in each region.
Sorry.
Richard
I swear, you can’t make this stuff up!
Oh.
Sorry, my bad.