From the Helmholtz Centre for Ocean Research Kiel (GEOMAR)
New perspectives for long-term climate predictions?
This image shows a time series of solar activity (bottom) and the North Atlantic Oscillation in two model simulations, without (blue) and with (yellow) solar forcing. Credit, GEOMAR.
Are climate predictions over periods of several years reliable if weather forecast are still only possible for short periods of several days? Nevertheless there are options to predict the development of key parameters on such long time scales. A new study led by scientists at GEOMAR Helmholtz Centre for Ocean Research Kiel shows how the well-known 11-year cycle of solar activity affects the long-time development of dominant large-scale pressure systems in the Northern Hemisphere.
For their investigations the scientists used a coupled ocean-atmosphere model. In addition, this model includes an interactive chemistry module which can for instance cope with the effect of ultraviolet radiation (UV) in the upper atmosphere. This additional component seemed to be key to transmit the variations in the solar radiation which might have only a small direct impact on the earth’s surface, through a complex mechanism from the stratosphere (10-50 km altitude) to the lower atmosphere.
“We have carried out several experiments,” says Dr. Rémi Thiéblemont from GEOMAR, lead author of the study. “We conducted model experiments over a period of 145 years, with and without the influence of solar activity “, Thiéblemont continued. The sun’s influence could clearly be identified in the so-called North Atlantic Oscillation, which is roughly speaking the pressure difference between the Azores high and the Iceland low. The ratio between these two pressure systems often determines the weather in Europe over longer time periods, such as whether the winter months turn warm and stormy or cold and snowy. The researchers found a time lag between variations in solar irradiance and atmospheric pressure patterns of about one to two years, which can be explained by an interaction between the atmosphere and the ocean. By comparing the two experiments with or without solar activity, they were able to prove for the first time that the sun irradiance serves as a phase-lock for the North Atlantic Oscillation. With this context, an increase of the predictability of the decadal NAO phase can be expected.
“The fact that the circulation in the upper atmosphere responds significantly to the solar fluctuations, is already known”, Prof. Dr. Katja Matthes, initiator and co-author of the study from GEOMAR explains. “On one hand we can demonstrate with this new study how the transmission of the signal to the Earth’s surface and its interaction with the ocean works, and on the other hand we can show the importance of the chemical reactions for the coupling”, Prof. Matthes continued. So far, most global climate models have neither a sufficient resolution in the stratosphere nor interactive chemical components. “Although the solar effect on the North Atlantic Oscillation explains only a few percent of the total variance, the close relationship between solar activity and phase North Atlantic Oscillation is an important indicator to improve the predictability of climate variability”, Dr. Thiéblemont summarizes.
There is still a long way to go, for successful and reliable long-term forecasts up to a decade. Nevertheless, for successful predictions it is important to include solar fluctuations, Professor Matthes concludes.
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Scientific paper:
Thiéblemont, R., K. Matthes, N.-E. Omrani, K. Kodera and F. Hansen, 2015. Solar forcing synchronizes decadal climate variability North Atlantic. Nature Communications, doi: 10.1038/ncomms9268.
Quel surprise.
And now for the inevitable and interesting discussion.
I stopped reading after I saw in the caption, “two model simulations.”
Another one for Willis to pull apart. LOL
You read it first in my ‘Chill:a reassessment of global warming theory (2009)’!
One – that UV light variability would eventually be found responsible for correlations to solar cycles; Two – there would be a link to ocean oscillations (the counter-theory being some kind of internal stochastic resonance dynamic).
Note however that this group assume solar UV will continue much as before….I doubt this. There are longer term cycles that may also be the result of UV flux and hence longer term solar variability (cycles). The changes in circulation that they talk about can result in blocking high pressure systems – there has been one in the North Pacific for more than a year now, probably responsible for the Californian drought and current global high temperatures (with help also from ENSO). A similar block in the North Atlantic in winter will lead to deep cold in western Europe.
There is a real potential now for global cooling in the next three years – as ENSO fades, as the pressure system in the North Pacific shifts, and a North Atlantic block builds up – and all this coincident with a declining solar cycle and low UV flux and negative AMO (which may be linked) – which will mean that the ‘pause’ is not only extended, but cooling evident from the year 2000 onward to at least 2018 and most likely 2030 if the next solar cycle is also low (as I suspect it will be).
“Ocean currents affect the surface temperature of the oceans and thus the heat exchange with the atmosphere – eventually causing climate variations on the adjacent continents. The most evident is an oscillation with a period of 60 years. “Such decadal climate fluctuations are superimposed on the general warming trend, so that at times it seems as if the warming trend slowed or even stopped. After a few decades, it accelerates once again,” explains Prof. Latif. “It is important for us to understand these natural cycles, so that we can finally provide better climate predictions as well.”
Read more at: http://phys.org/news/2013-07-marine-scientists-decoding-mechanism-long-term.html#jCp
Solar flux prediction 100 years ahead- a bit of nonsense.
Well, it does put two more “spheres” into the models, stratosphere and heliosphere.
“Although the solar effect on the North Atlantic Oscillation explains only a few percent of the total variance, ”
Say what? So the solar effect is very, very small. But we already knew that.
Will we see an obvious call for more funding for the authors?
Oh yeah, there it is:
“There is still a long way to go, for successful and reliable long-term forecasts up to a decade. Nevertheless, for successful predictions it is important to include solar fluctuations, Professor Matthes concludes.”
I’ve been covering the same ground since 2010.
Latest version here:
http://joannenova.com.au/2015/01/is-the-sun-driving-ozone-and-changing-the-climate/
“What is the role of the global ocean circulation in low-frequency climate variability in the North Atlantic region? More than 50 years ago, Bjerknes suggested that the character of large-scale air-sea interaction over the mid-latitude North Atlantic Ocean differs with timescales: the atmosphere was thought to drive directly most short-term (interannual) sea surface temperature (SST) variability, and the ocean to contribute significantly to long-term (multidecadal) SST and potentially atmospheric variability. Such a relationship is also suggested by a number of global climate models in which the Atlantic Meridional Overturning Circulation (AMOC) plays a major role in driving multidecadal SST variability.”
http://www.geomar.de/typo3temp/pics/2015-03-30-heat_flux_01_ab0fc465ed.jpg
Professor Matthes is right. It is important to include the sun.
I think first the past needs more conclusive understanding wrt solar influence on the climate before achieving “forecasting up to a decade”. N’est ce pas?
John
When solar activity enters a prolonged minimum period of activity look for a negative AO/NAO.
Fitting, again. What one would love to see in any or all of these curve-fitting theories is a provable prediction, or mechanism subject to measurement or observation. But then I’m an Oxfordshire housewife with only a housewife’s grasp of such things.
It’s interesting mathematical work. However, it still ends up as a “We took this out and it broke our model” method. That’s not a valid tactic for evaluating whether something is real.
That said, the evaluation of lag between solar activity and the NAO is a good one, though I wonder why they would need a model for that, as it’s a historical analysis, and it appears that they properly qualified their results, and it does provide a suggestion for a causal link.
While it seems like a likely reasult and I agree with the general tone and direction, this isn’t evidence. Just because it makes your model fit better doesn’t mean that an effect or connection is real.
I see two wiggles under each other, is there also a statistical correlation that exceeds 30%?
Well, there you go…
“they were able to prove for the first time that the sun irradiance serves as a phase-lock for the North Atlantic Oscillation”
It is the sun stupid.
>> I wonder why they would need a model for that
You people are seriously confused and pseudo-scientific. Every equation or group of equations IS a MODEL of reality. There is no conceptual difference between F=ma and this author’s model. In fact, F=ma ranks lower since it has been defined to be true. It predicts nothing.
You people complaining about adjusting a model to better fit observation implying that there is something wrong with that are also criticizing Einstein for adding terms to improve Newtonian models for gravity.
For a
theoryhypothesis that is regularly opposed by the mainstream, it sure does seem to have legs. GKThe top chart suggests that all these forcings are oscillatory. If we were to paste a line of global surface temperatures on that figure we’d see that it showed a strong warming trend.
For instance, everything in the top chart is pointing downwards since 2013, yet global surface temperatures are hitting all time highs in 2014 and now 2015 (with 2016 also likely to be very warm).
The only reasonable conclusion from that observation is that the warming wasn’t caused by solar activity.
In the SOL experiment, a statistically significant warming with a maximum of 0.9 K is observed near the tropical stratopause (3–1 hPa≈45–50 km) at lag −1 year of the NAO-based composites (Fig. 3a). This positive temperature anomaly arises from increased solar ultraviolet irradiance during solar cycle maximum phases, which leads to additional heating due to ozone absorption in the upper stratosphere and more ozone production in the mid and upper stratosphere through the photolysis of oxygen28. A secondary warming anomaly of 0.8 K appears in the lower equatorial stratosphere (~70 hPa or 20–25 km). Although less well understood than the direct upper stratospheric response, this secondary warming could arise from adiabatic warming13 combined with increased ozone heating29 due to a deceleration of the Brewer-Dobson circulation. The two temperature responses to the 11-year solar cycle are in reasonable agreement with reanalyses30, 31. Consistent with the 11-year solar cycle/NAO lagged relationship (Figs 1 and 2), the maximum temperature response in the stratosphere due to 11-year solar variability leads the NAO by 1 year. Conversely, none of these typical solar signals is observed in the NO_SOL experiment which instead shows a seesaw of positive (negative) temperature anomalies in the middle tropical and subtropical stratosphere (20–3 hPa) in winter (Fig. 3b).
Did they find something?
michael
None of this explains the global temperature trend over the last century – or even over the last 30 years. The AMO index has wiggled around some calculated mean but is generally trendless. It might explain shifts in weather patterns – particularly in the NH – but it tells us nothing about energy accumulation in the climate system.
The fact that there may be some link between solar activity and the AMO is irrelevant as far as any influence
that greenhouse gases may have.
Are climate predictions over periods of several years reliable if weather forecast are still only possible for short periods of several days?…..
….no, predicting climate is easier
The paper could be valuable, but it wont get very much attention. It lacks the maybe, possible, could be looming catastrophe if you don’t do anything or investigate more.
The RSS data set will have enough data to see 11 year cycles in 1979 + 11*4 = 2023. That’s not too far off. And RSS captures temperatures in the upper atmosphere. So if there’s an 11 year cycle that affects the upper atmosphere, it’s either visible now in the RSS data (if it’s very large signal) or will soon be visible if it’s a medium-sized signal.
As far as seeing 60 year AMOC cycle, we have to wait till at least 2099 assuming the signal is large.
Peter
I haven’t read the paper yet, but do they isolate their characterization of the stratospheric chemistry relationships?