From Cardiff University
Sun’s energy influences 1,000 years of natural climate variability in North Atlantic
Changes in the sun’s energy output may have led to marked natural climate change in Europe over the last 1000 years, according to researchers at Cardiff University.
Scientists studied seafloor sediments to determine how the temperature of the North Atlantic and its localised atmospheric circulation had altered. Warm surface waters flowing across the North Atlantic, an extension of the Gulf Stream, and warm westerly winds are responsible for the relatively mild climate of Europe, especially in winter. Slight changes in the transport of heat associated with these systems can led to regional climate variability, and the study findings matched historic accounts of climate change, including the notoriously severe winters of the 16th and 18th centuries which pre-date global industrialisation.
The study found that changes in the Sun’s activity can have a considerable impact on the ocean-atmospheric dynamics in the North Atlantic, with potential effects on regional climate.
Predictions suggest a prolonged period of low sun activity over the next few decades, but any associated natural temperature changes will be much smaller than those created by human carbon dioxide emissions, say researchers.
The study, led by Cardiff University scientists, in collaboration with colleagues at the University of Bern, is published today in the journal Nature Geoscience.
Dr Paola Moffa-Sanchez, lead author from Cardiff University School of Earth and Ocean Sciences, explained: “We used seafloor sediments taken from south of Iceland to study changes in the warm surface ocean current. This was done by analysing the chemical composition of fossilised microorganisms that had once lived in the surface of the ocean. These measurements were then used to reconstruct the seawater temperature and the salinity of this key ocean current over the past 1000 years.”
The results of these analyses revealed large and abrupt temperature and salinity changes in the north-flowing warm current on time-scales of several decades to centuries. Cold ocean conditions were found to match periods of low solar energy output, corresponding to intervals of low sunspot activity observed on the surface of the sun. Using a physics-based climate model, the authors were able to test the response of the ocean to changes in the solar output and found similar results to the data.
“By using the climate model it was also possible to explore how the changes in solar output affected the surface circulation of the Atlantic Ocean,” said Prof Ian Hall, a co-author of the study. “The circulation of the surface of the Atlantic Ocean is typically tightly linked to changes in the wind patterns. Analysis of the atmosphere component in the climate model revealed that during periods of solar minima there was a high-pressure system located west of the British Isles. This feature is often referred to as atmospheric blocking, and it is called this because it blocks the warm westerly winds diverting them and allowing cold Arctic air to flow south bringing harsh winters to Europe, such as those recently experienced in 2010 and 2013.”
Meteorological studies have previously found similar effects of solar variability on the strength and duration of atmospheric winter blockings over the last 50 years, and although the exact nature of this relationship is not yet clear, it is thought to be due to complex processes happening in the upper layers of the atmosphere known as the stratosphere.
Dr Paola Moffa-Sanchez added: “In this study we show that this relationship is also at play on longer time-scales and the large ocean changes, recorded in the microfossils, may have helped sustain this atmospheric pattern. Indeed we propose that this combined ocean-atmospheric response to solar output minima may help explain the notoriously severe winters experienced across Europe between the 16th and 18th centuries, so vividly depicted in many paintings, including those of the famous London Frost Fairs on the River Thames, but also leading to extensive crop failures and famine as corroborated in the record of wheat prices during these periods.”
The study concludes that although the temperature changes expected from future solar activity are much smaller than the warming from human carbon dioxide emissions, regional climate variability associated with the effects of solar output on the ocean and atmosphere should be taken into account when making future climate projections.
Notes for Editors:
Funding for this research has come from the Natural Environment Research Council, UK, the National Science Foundation, Switzerland, the European Commission and NCAR’s Computational and Information Systems Laboratory (CISL). This research forms part of the Climate Change Consortium of Wales (C3W; http://c3wales.org/).
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The paper:
Solar forcing of North Atlantic surface temperature and salinity over the past millennium
Paola Moffa-Sánchez, Andreas Born, Ian R. Hall, David J. R. Thornalley & Stephen Barker
Nature Geoscience (2014) doi:10.1038/ngeo2094
Abstract:
There were several centennial-scale fluctuations in the climate and oceanography of the North Atlantic region over the past 1,000 years, including a period of relative cooling from about AD 1450 to 1850 known as the Little Ice Age1. These variations may be linked to changes in solar irradiance, amplified through feedbacks including the Atlantic meridional overturning circulation2. Changes in the return limb of the Atlantic meridional overturning circulation are reflected in water properties at the base of the mixed layer south of Iceland. Here we reconstruct thermocline temperature and salinity in this region from AD 818 to 1780 using paired δ18O and Mg/Ca ratio measurements of foraminifer shells from a subdecadally resolved marine sediment core. The reconstructed centennial-scale variations in hydrography correlate with variability in total solar irradiance. We find a similar correlation in a simulation of climate over the past 1,000 years. We infer that the hydrographic changes probably reflect variability in the strength of the subpolar gyre associated with changes in atmospheric circulation. Specifically, in the simulation, low solar irradiance promotes the development of frequent and persistent atmospheric blocking events, in which a quasi-stationary high-pressure system in the eastern North Atlantic modifies the flow of the westerly winds. We conclude that this process could have contributed to the consecutive cold winters documented in Europe during the Little Ice Age.
Spin;-{
The Universe rotates.
the World wobbles.
Volcanoes blow.
Water moves.
Wind blows.
Moon orbits.
Spotty Sun shines.
Humankind affects it all?
Now if they can expand their research to explain why LIA was not just a regional event, but a global event.
“Predictions suggest a prolonged period of low sun activity over the next few decades, but any associated natural temperature changes will be much smaller than those created by human carbon dioxide emissions…”
(http://science.gsfc.nasa.gov/sed/index.cfm?fuseAction=datatools.view&&project_id=38&navOrgCode=610&navTab=nav_researchers) NASA:
“The second finding is crucial in understanding the physical mechanisms of the impact of solar variation on Earth’s climate. Based on SIM observations Cahalan et al. [2010] demonstrate remarkable different climate responses (stratosphere, troposphere, ocean mixed layer) to SORCE-based and proxy-based SSI variations. The out-of-phase SSI variations also have implications to re-examine the connection of the Sun and stratosphere, troposphere, biosphere, ocean, and Earth’s climate. […]”
“… and how solar variations influence the Earth’s climate over long time scales REMAIN UNRESOLVED.”
NOAA (http://www.ncdc.noaa.gov/faqs/climfaq10.html ) :
“… our understanding of the indirect effects of changes in solar output and feedbacks in the climate system is minimal […]
Is sufficient compare these three quotes to demonstrate the pseudoscientific nonsense contained in the first citation – no basis for such an axiomatic level of certainty in this type of works – papers.
I only “Like you, I hope for more studies along these lines.” Not solely about positive feedbacks antr. CO2 …
Fool agree with Sparks.
Full agree with Sparks, of course, sorry for the mistake.
You are not interpreting his “25%” correctly. He believes that we really don’t know what the four factors x,y,z and w are. Therefore, to be fair (printsip bezrazlichiya nye pravda li?), one cannot give any factor more credit than the other. So they all get 25%.
So his stance has not changed. He still does not believe that solar magnetic activity has been shown to have any significant effect on climate, but is being fair about and leaving unbiased room for doubt.
😐
“Predictions suggest a prolonged period of low sun activity over the next few decades, but any associated natural temperature changes will be much smaller than those created by human carbon dioxide emissions, say researchers.”
Regionally in the north hemisphere cold outbreaks will depend on how deep the negative AO/NAO episodes are, which in the past few years has been as low as during the last weak solar cycles 12-14 in the 1880-90’s. I don’t think that +/-0.5°C average global temperature makes much difference
“Cold ocean conditions were found to match periods of low solar energy output, corresponding to intervals of low sunspot activity observed on the surface of the sun.”
So why was the AMO in a positive phase during the 1880-90’s?
Alexander Feht says:
March 11, 2014 at 3:02 am
I remember time (not so long ago) when Dr. Svalgaard refused to attribute any warming or cooling to the solar activity.
Your venom has gotten the better of you. Just due to the solar cycle one must expect at least a 0.1C variation as I have always maintained. Now, there are people who claim that not even that will happen, i.e. that there are long-term effects without any underlying short-term [cycle] effect.
Ulric:
A better question might be, why is it that AMO/NAO are so cyclic?
http://climatedatablog.files.wordpress.com/2014/02/esrl-reconstructed-monthly-nao-rnao-monthly-anomalies.png
and how does that relate to CET
http://climatedatablog.wordpress.com/cet/
RichardLH says:
“Ulric: A better question might be, why is it that AMO/NAO are so cyclic?”
My question “why was the AMO in a positive phase during the 1880-90′s?” was pertinent to their claim that:
“Cold ocean conditions were found to match periods of low solar energy output, corresponding to intervals of low sunspot activity observed on the surface of the sun.”
as solar cycles 12-14 were weak, which seems to contradict their claim. I was not concerned with the cyclicity as such.
Janice Moore says:
March 10, 2014 at 3:53 pm
Dear Dr. Svalgaard,
Re: “We do not know what x, y, z, and w are.”
Thank you.
Janice
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Dear Janice Moore,
I hate to rock your giddy boat, but I hope you understand that Dr. Svalgaard is not agreeing with your BOLD view. Not identifying specific percentages for x, y, z, and w is not the same as “NO evidence that human CO2 does ANYTHING to raise or lower the temperature of the earth”. The Dr. does assume a value for “y”, however arbitrary and vague, and there is considerable scientific research that supports impacts of CO2 and land use, for example. Anyway, have a nice day, and enjoy your fantasy. lol
Ulric: I have great doubts as to if sun activity can responsible to the temperature outcomes. They are trying to match cyclicity in that to temperature. There are other cylicities that may be more important.
If one includes Volcanism as a factor http://wattsupwiththat.com/2014/03/10/volcano-activity-temperature-and-response-times/ then we have x, y, z, w, and v. This lowers the equal assignment from 25% to 20%. At this point there is no compelling values that everyone can agree on [as is required for a mature science].
RichardLH says:
“Ulric: I have great doubts as to if sun activity can responsible to the temperature outcomes.”
With such a good correlation between negative NAO with weak solar cycles in late Maunder, Dalton, solar cycles 12-14, and currently?
http://climatedatablog.files.wordpress.com/2014/02/esrl-reconstructed-monthly-nao-rnao-monthly-anomalies.png
Ulric: Co-incidence is not a conclusion, only an observation. You do rather need a mechanism that connects on e to the together and that is what is missing.
Ulric: PDO and AMO/NAO show consistent cyclic behaviour that is not well represented by any solar output figures.
http://climatedatablog.wordpress.com/pdo/
http://climatedatablog.wordpress.com/amo/
lsvalgaard says:
March 11, 2014 at 8:30 am
If one includes Volcanism as a factor http://wattsupwiththat.com/2014/03/10/volcano-activity-temperature-and-response-times/ then we have x, y, z, w, and v. This lowers the equal assignment from 25% to 20%. At this point there is no compelling values that everyone can agree on [as is required for a mature science].
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And one should not forget cow farts, add q to the equation. Let’s see, that brings equal assignment to 16.67% … {rolls eyes & laughs}
Janice Moore says:
March 10, 2014 at 2:43 pm
@ur momisugly Latitude: “…less than zero.” Yes.
Perhaps, I was wrong. It appears that Dr. Svalgaard DOES support AGW by that comment (emphasizing “much smaller”). Aaack. I don’t want to think that!
++++++++++++
Janice: As humans, we’re wired to want our team to win. Thinking is subjective my dear:) Truth, however and being “willing” to change what we think leads to growth. There is no doubt in my mind that the presence of CO2 should cause warming. So at least it passes the smell test for me. The question is, and always has been about, how much warming will a doubling of CO2 cause? I’m happy to delve into this more in plane English.
The problem is with the “other team”, in that they claim that most of the warming was caused by the additional CO2. The only evidence of this (most of the warming is caused by CO2) has been in the climate models. Further, the models don’t show that CO2 caused most of the warming; rather they have shown that CO2 drives the process, and that secondary feedbacks amplify the process. The models are not supported by observations. They got it wrong – very wrong.
There is ample evidence that warming from CO2 has a logarithmic affect on temperature. Said another way, after a certain relatively small concentration of CO2, the cumulative effects are rather small. The IPCC knows or at least believes this part, but they are confused or dishonest about the rest of what I am going to write here.
Since the CAGW movement began, we’ve learned a lot about secondary feedbacks… and Richard Lindzen has illustrated (using Satellite data of the atmosphere at various levels) that the feedbacks range from positive to negative – (not just positive) and on the net, the feedbacks have been slightly negative –exactly the opposite to what the IPCC hoped for or claims. For example, observations show that there is no tropical hotspot, which was a cornerstone of the CAGW claim. They claimed that the release of extra methane, water vapor, and CO2 would start us into a tipping point of sorts, where we’d get this runaway self feeding one directional warming.
There is no tropical hotspot… What actually happened was that as the planet warmed on average, more energy radiated into space. Willis writes a lot about the Thermostatic effect, and supports this based on observations. Richard Lindzen theorized on the Iris affect… which I think is similar – but not the same as what Willis shows. I am oversimplifying my understanding here.
Keep on posting and cheering! You’re making us think!
Well thanks for that Richard, I may just try that a little later. Right now, I have to jump on the #18 train from CERN (end of line) and go downtown to l’hopital , to see how Sis is doing.
George
“low solar irradiance promotes the development of frequent and persistent atmospheric blocking events”
How dare they claim something other than carbon pollution is the cause of extreme weather.
Burn the heretic!
lsvalgaard says:
March 11, 2014 at 8:30 am
“If one includes Volcanism as a factor http://wattsupwiththat.com/2014/03/10/volcano-activity-temperature-and-response-times/ then we have x, y, z, w, and v. This lowers the equal assignment from 25% to 20%. At this point there is no compelling values that everyone can agree on [as is required for a mature science].”
So, for the last 17.5 years the net effect all of these is 0, or each is worth 20% of nothing, take your pick. It would seem logical to recognize the two very large beasts in the room; the Sun, and the oceans which cover 70% of the planet, as being very big players in this game of climate, one way or another. One might add volcanism if considered as a variable heat source to the oceans rather than just a shading system for cooling the planet. So many variables, so few linear relationships=chaotic system. Should be fun attempting to find answers for a long time. So far the only systematic events which seem to make sense are the Milankovich cycles, but one needs to only be concerned with huge time periods to get much out of them.
@ur momisugly John E. F. (7:49am today) — To “assume a value for “y”, does not logcially negate Dr. Svalgaard’s statement: “We do not know what x, y, z, and w are.” (emphasis mine).
IIRC, Dr. Svalgaard regularly asserts on WUWT that while variations in solar irradiance cause minor variations in earth’s temperature within a narrow range which maintains earth’s homeostasis, so far, there is no evidence that these solar variations cause climate shifts which are more likely driven by the oceans and other natural drivers.
I agree with him.
Boy, I sounded pretty giddy just then, huh? LOL, Mr. F. — you ought to see me at a party! Once, I was accused of drinking more than my share of the wine — and I had only been drinking pop!! And that is a typical scenario… .
I may be “giddy” in your eyes, but, for now at least, you are illogical (but, I’ll assume simply by an anomalous mistake) in mine. But, we can still be friends, can we not?
Hopeful that we can communicate in a more friendly manner from now on,
Janice
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Dear Mario,
Thanks for letting me know what you think about the effect of CO2 on climate. I’m with Murry Salby (perhaps, you are too — not sure from your comment) — temperature drives CO2 increase, not vice versa. Thank you for taking the time to patiently explain things to a non-scientist.
And for the encouragement to keep on cheering. I needed that after John E. F.. I like me, but, well, he kind of threw a wet towel from the men’s locker room in this cheerleader’s face’. Won’t be long, though, till I’m dried off and jumping up and down and yelling: “W — U — W — T! … we are the best, B — E — S — T and we are boss, B — O — S — S, B — O — S — S, BOSS! Goooooo Wattsup!”
#(:))
Your WUWT pal,
Janice
Dear Janice: Regarding: “Thanks for letting me know what you think about the effect of CO2 on climate. I’m with Murry Salby (perhaps, you are too — not sure from your comment) — temperature drives CO2 increase, not vice versa. Thank you for taking the time to patiently explain things to a non-scientist.”
++++++
It’s not so simple. Yes – you’ll often hear me saying that all evidence shows that CO2 levels follow temperature. But that fact does not disprove what I wrote below in any way. What I wrote is typically the skeptical argument based on science of what we do know. Said another way, that increasing temperature releases CO2 from solution, does not also mean that CO2 can’t have a positive or negative feedback effect. It is not as simple as an either/or outcome. Nor is it about whether or not someone agrees or disagrees. A fact about anything does not rely on whether someone believes it is a fact.
If I cannot explain this to you, then I need to learn how to be a better communicator. 🙂
l have real doubts that the cause of ice ages is all down to changes in the tilt/orbit of the earth.
l cannot see how with the present weather patterns in place over the North Atlantic. That these effects could make it so cold in europe as to bring the ice sheets all the way down England and yet leave NE Russia largely ice free. But l could see how a change in the weather pattern over the North Atlantic just maybe able to explain it.
RichardLH says:
“Ulric: PDO and AMO/NAO show consistent cyclic behaviour that is not well represented by any solar output figures.”
It looks more like step changes than a cycle in the AMO to me, as in the mid 1920’s.
England may well be wet, but only a few miles north Scotland is also ‘wet’ but in a snow sort of way.
http://www.bbc.co.uk/news/uk-scotland-highlands-islands-26339994
Were the weather patterns to have tracked just a few miles further south then the whole of the UK might look the same.