“Skaters can only do this race every 10 or 11 years because that’s when the rivers freeze up,” Sirocko said. “I thought to myself, ‘There must be a reason for this,’ and it turns out there is.”
WASHINGTON – Scientists have long suspected that the Sun’s 11-year cycle influences climate of certain regions on Earth. Yet records of average, seasonal temperatures do not date back far enough to confirm any patterns. Now, armed with a unique proxy, an international team of researchers show that unusually cold winters in Central Europe are related to low solar activity – when sunspot numbers are minimal. The freezing of Germany’s largest river, the Rhine, is the key.
Although the Earth’s surface overall continues to warm, the new analysis has revealed a correlation between periods of low activity of the Sun and of some cooling – on a limited, regional scale in Central Europe, along the Rhine.
“The advantage with studying the Rhine is because it’s a very simple measurement,” said Frank Sirocko lead author of a paper on the study and professor of Sedimentology and Paleoclimatology at the Institute of Geosciences of Johannes Gutenberg University in Mainz, Germany. “Freezing is special in that it’s like an on-off mode. Either there is ice or there is no ice.”
From the early 19th through mid-20th centuries, riverboat men used the Rhine for cargo transport. And so docks along the river have annual records of when ice clogged the waterway and stymied shipping. The scientists used these easily-accessible documents, as well as additional historical accounts, to determine the number of freezing episodes since 1780.
Sirocko and his colleagues found that between 1780 and 1963, the Rhine froze in multiple places 14 different times. The sheer size of the river means it takes extremely cold temperatures to freeze over making freezing episodes a good proxy for very cold winters in the region, Sirocko said.
Mapping the freezing episodes against the solar activity’s 11-year cycle – a cycle of the Sun’s varying magnetic strength and thus total radiation output – Sirocko and his colleagues determined that ten of the fourteen freezes occurred during years around when the Sun had minimal sunspots. Using statistical methods, the scientists calculated that there is a 99 percent chance that extremely cold Central European winters and low solar activity are inherently linked.
“We provide, for the first time, statistically robust evidence that the succession of cold winters during the last 230 years in Central Europe has a common cause,” Sirocko said.
With the new paper, Sirocko and his colleagues have added to the research linking solar variability with climate, said Thomas Crowley, Director of the Scottish Alliance for Geoscience, Environment, and Society, who was not involved with the study.
“There is some suspension of belief in this link,” Crowley said, “and this study tilts the argument more towards thinking there really is something to this link. If you have more statistical evidence to support this explanation, one is more likely to say it’s true.”
The study, conducted by researchers at Johannes Gutenberg and the Institute for Atmospheric and Climate Science in Zurich, Switzerland, is set to be published August 25 in Geophysical Research Letters, a journal of the American Geophysical Union.
When sunspot numbers are down, the Sun emits less ultraviolet radiation. Less radiation means less heating of Earth’s atmosphere, which sparks a change in the circulation patterns of the two lowest atmospheric levels, the troposphere and stratosphere. Such changes lead to climatic phenomena such as the North Atlantic Oscillation, a pattern of atmospheric pressure variations that influences wind patterns in the North Atlantic and weather behavior in regions in and around Europe.
“Due to this indirect effect, the solar cycle does not impact hemispherically averaged temperatures, but only leads to regional temperature anomalies,” said Stephan Pfahl, a co-author of the study who is now at the Institute for Atmospheric and Climate Science in Zurich.
The authors show that this change in atmospheric circulation leads to cooling in parts of Central Europe but warming in other European countries, such as Iceland. So, sunspots don’t necessarily cool the entire globe – their cooling effect is more localized, Sirocko said.
In fact, studies have suggested that the extremely cold European winters of 2010 and 2011 were the result of the North Atlantic Oscillation, which Sirocko and his team now link to the low solar activity during that time.
The 2010 and 2011 European winters were so cold that they resulted in record lows for the month of November in certain countries. Some who dispute the occurrence of anthropogenic climate change argue that this two-year period shows that Earth’s climate is not getting any warmer. But climate is a complex system, Sirocko said. And a short-term, localized dip in temperatures only temporarily masks the effects of a warming world.
“Climate is not ruled by one variable,” said Sirocko. “In fact, it has [at least] five or six variables. Carbon dioxide is certainly one, but solar activity is also one.”
Moreover, the researchers also point out that, despite Central Europe’s prospect to suffer colder winters every 11 years or so, the average temperature of those winters is increasing and has been for the past three decades. As one piece of evidence of that warming, the Rhine River has not frozen over since 1963. Sirocko said such warming results, in part, from climate change.
To establish a more complete record of past temperature dips, the researchers are looking to other proxies, such as the spread of disease and migratory habits.
“Disease can be transported by insects and rats, but during a strong freezing year that is not likely,” said Sirocko. “Also, Romans used the Rhine to defend against the Germanics, but as soon as the river froze people could move across it. The freezing of the Rhine is very important on historical timescales.”
It wasn’t, however, the Rhine that first got Sirocko to thinking about the connection between freezing rivers and sunspot activity. In fact, it was a 125-mile ice-skating race he attended over 20 years ago in the Netherlands that sparked the scientist’s idea.
“Skaters can only do this race every 10 or 11 years because that’s when the rivers freeze up,” Sirocko said. “I thought to myself, ‘There must be a reason for this,’ and it turns out there is.”
Title:
“Solar influence on winter severity in central Europe”
Abstract:
The last two winters in central Europe were unusually cold in comparison to the years before. Meteorological data, mainly from the last 50 years, and modelling studies have suggested that both solar activity and El Niño strength may influence such central European winter coldness. To investigate the mechanisms behind this in a statistically robust way and to test which of the two factors was more important during the last 230 years back into the Little Ice Age, we use historical reports of freezing of the river Rhine. The historical data show that 10 of the 14 freeze years occurred close to sunspot minima and only one during a year of moderate El Niño. This solar influence is underpinned by corresponding atmospheric circulation anomalies in reanalysis data covering the
period 1871 to 2008. Accordingly, weak solar activity is empirically related to extremely cold winter conditions in Europe also on such long time scales. This relationship still holds today, however the average winter temperatures have been rising during the last decades.
Authors:
Frank Sirocko and Heiko Brunck: Institute of Geosciences, Johannes Gutenberg University Mainz;
Stephan Pfahl: Institute for Atmospheric and Climate Science, ETH Zurich, Switzerland.
==============================================================
I hope to have a copy of the paper soon – Anthony
UPDATE: Dr. Leif Svalgaard provides the paper, as did the AGU press agent Kate Ramsayer per my emailed request, along with a copyright admonishment. Thank you both. Figure 6a and 6b are interesting:
From the paper:
In agreement with the 20th Century Reanalysis central European temperature observations from the CRUTEM3 dataset [Brohan et al., 2006] from winters directly following a sunspot minimum are also significantly lower than the average temperature during the remaining winter seasons (Fig. 6a). The relation between cold winter conditions and sunspot activity is thus not specific to rivers alone (which could also be affected by a number of additional factors, for example warm water from the numerous powerplants constructed along the river). The strong variations of the time series in Fig. 6a, which are largely independent of the sunspot cycle, show the important role of internal, stochastic variability of the atmosphere for European winter temperatures. The relation shown above holds true only for central European temperatures. When the CRUTEM3 winter temperature data are averaged over the whole Northern Hemisphere, no relation to the solar minima is found.
This suggests a regional circulation pattern effect, as the authors state connected to figure 5a and 5b:
To identify the atmospheric circulation anomalies in the North Atlantic and European region associated with cold winters during solar minima, Fig. 5a shows the difference in the geopotential height fields at 500 hPa (Z500) between the winters directly following a year with a sunspot minimum and the remainder of the period 1871 to 2008, obtained from the 20th Century Reanalysis dataset [Compo et al., 1996]. A strong, statistically significant positive anomaly occurs over the eastern North Atlantic in the region of Iceland, while negative anomalies are found over the Iberian peninsula and over north-eastern Europe (the latter being not significant). These Z500 anomalies are associated with an enhanced northerly flow and cold air advection from the Arctic and Scandinavia
towards central Europe, leading to significantly negative temperature anomalies over England, France and western Germany (Fig. 5b). The centre of the cooling is in the region of southern England, the Benelux countries and western Germany down to middle Rhine area. Eastern and southern Germany are not effected as much as the above region. Accordingly, it is only the Rhine and possible some Dutch rivers that provide the possibility to reconstruct this specific temperature anomaly pattern, which corresponds to an anomalously negative NAO and a preference for blockings over the eastern North Atlantic.
Jim G says:
August 23, 2012 at 12:37 pm
Not necessarily. Not everyone thinks totally in black and white terms when complex systems are involved where other variables may have an effect. Open your mind.
Several weasel words: ‘not necessarily’, ‘not everyone’, ‘may have’. Provide numbers and data, please.
Stephen Wilde says:
August 23, 2012 at 12:41 pm
The 5 cycles leading up to 1900 and those leading up to now are somewhat different
As far as UV and solar wind were concerned, the cycles in the middle of the 19th century were similar to the last 5 cycles. That is the important piece. Now, if UV and solar wind have nothing to do with the climate, I agree that this is irrelevant.
HenryP said:
“1963 is ca. 18 years of warming from the end of a cooling period. We are currently 17 years into cooling period from a warming period. Assuming complete symmetry I calculate that the rate of warming in 1963 will be the same as the rate of cooling in 2013.”
Nothing in nature gives complete symmetry. Aren’t the past two European winters cold enough to have made your point ?
December in the UK had temperatures colder than 1963 and it was only fortuitous and due to the vagaries of short term variability that it didn’t last as long:
http://en.wikipedia.org/wiki/Heavy_Snowfall_of_Late_2010_in_the_United_Kingdom
There have been lots of southern hemisphere cold outbreaks too and not long ago China decalred a climate emergency during a fierce cold spell.
Those events are outside the range of what we had become used to over the previous 3 decades.
Leif Svalgaard says: August 23, 2012 at 10:53 am
No, NASA does not support any of your speculations.
Of course NASA doesn’t speculate, they do research, I do the speculation.
Of course NASA doesn’t support my speculations, that would be far too embarrassing.
But they do come ‘damn close’ to it:
Vukcevic 17 September 2009
“The author postulates the existence of a high correlation between North Atlantic Temperature
Anomaly and the variations of magnetic field …the underlying mantle uplift (as reflected in changes of the area’s magnetic intensity) are making significant contribution to the Atlantic basin climate change.”
NASA / JPL 09 March, 2011 (Jean Dickey and Steven Marcus)
“movements of Earth’s core might disturb Earth’s magnetic shielding of charged-particle (i.e., cosmic ray) fluxes that have been hypothesized to affect the formation of clouds. This could affect how much of the sun’s energy is reflected back to space and how much is absorbed by our planet. Other possibilities are that some other core process could be having a more indirect effect on climate, or that an external (e.g. solar) process affects the core and climate simultaneously.”
What NASA do (from Huntsville to Pasadena, from New York and Hampton to Merritt Island) is regularly look at the selection of my graphs, and that is far more support of my speculations than I would ever expect.
Leif said:
“As far as UV and solar wind were concerned, the cycles in the middle of the 19th century were similar to the last 5 cycles. That is the important piece. Now, if UV and solar wind have nothing to do with the climate, I agree that this is irrelevant.”
Now you have shifted from comparing 1900 to 2012 to comparing the mid 19th century with the late 20th.
Well the late 20th was further along the solar induced recovery from the LIA and so for the same activity levels one would expect more warmth in the late 20th.
Anyway looking at your figs the five cycles in the late 20th still look more active than the five cycles in the mid 19th.
Furthermore there was warming at the time of those high 19th century activity levels followed by an easing off towards the turn of the century before the warming of the early 20th century.
So, adjusting for the later position along the post LIA warming trend line and for the differences between the two groups of five cycles I’d say the late 20th century warming was comparable to the warming of the mid 19th.
That doesn’t lead to 2012 being the same as 1900 though so I think you are raising a straw man in proposing that it should be.
Leif Svalgaard says:
August 23, 2012 at 12:44 pm
Jim G says:
August 23, 2012 at 12:37 pm
Not necessarily. Not everyone thinks totally in black and white terms when complex systems are involved where other variables may have an effect. Open your mind.
“Several weasel words: ‘not necessarily’, ‘not everyone’, ‘may have’. Provide numbers and data, please.”
Here are some numbers. Out of 52 posts, so far, 8 are from Leif, 100% of those are closed minded. Though I would agree with a few of them, the tone is poor in all. Not a large enough sample size, yet, to quote statistical significance. Come on, Leif, have you no sense of humor?
The Weasel Worder
In re scaling, again I recommend Edward R. Tufte, The Visual Display of Quantitative Information. Cheshire, CT: Graphics Press. (2001, 2nd edition, ISBN 0-9613921-4-2).
I’d like to see some evidence of a sense of humour from Leif other than the put downs that are no doubt amusing to him.
I’d also like him to be as thick skinned as we need to be in dealing with him. The last time I matched his tone (usually I try not to react emotionally) he told me to tone down the rhetoric.
Note that these are just respectful suggestions rather than personal attacks.
Who moved the Rhine to Central Europe? Own up, now!
Leif-as far as the issue of lags go, lag is really not an appropriate word since it would imply that a simple shift would recover the full effect. This is generally incorrect. Because of the system’s properties it responds to “forcing” roughly as:
tau*dT/dt + T = lambda*F(t)
Where tau is the characteristic response time and lambda the “sensitivity” of the system.
Now, the thing to notice about this study is that it finds a very small impact of solar forcing over the eleven year cycle. In fact, over the whole Northern Hemisphere, any “minimum effect” is totally lost in the noise. Because of the nature of the response to forcing, this does not mean that there isn’t any effect: it just means we have to use physical theory, not merely correlating or composites to find the effects-the shorter the timescale, the less the response to any perturbation and the easier it is for the effect to be lost in the noise.
vukcevic says:
August 23, 2012 at 1:01 pm
Of course NASA doesn’t support my speculations, that would be far too embarrassing.
But they do come ‘damn close’ to it
I’m sure NASA doesn’t agree with that.
Stephen Wilde says:
August 23, 2012 at 1:03 pm
Now you have shifted from comparing 1900 to 2012 to comparing the mid 19th century with the late 20th.
Well the late 20th was further along the solar induced recovery from the LIA and so for the same activity levels one would expect more warmth in the late 20th.
No shift, the point is that there has been no progressive change in solar activity the last 300 years.
Anyway looking at your figs the five cycles in the late 20th still look more active than the five cycles in the mid 19th.
Now you have shifted from the late 20th to the mid 20th. The original comment was
“Peter C says:
August 23, 2012 at 9:56 am
after all, had not the sun been unusually active during the second half of the 20th. century?”
Perhaps look again:
http://www.leif.org/research/Solar-Activity-1835-2010.png
That doesn’t lead to 2012 being the same as 1900 though so I think you are raising a straw man in proposing that it should be.
The data shows 2008-2009 being the same as 1901-1902 and cycle 24 shaping up very much like cycle 14, yet climate is very different, in spite of UV and solar wind being the same.
Jim G says:
August 23, 2012 at 1:11 pm
Come on, Leif, have you no sense of humor?
Are you comments that laughable?
timetochooseagain says:
August 23, 2012 at 1:25 pm
this does not mean that there isn’t any effect: it just means we have to use physical theory,
I don’t see such use in the paper under discussion.
Jim G:
re your post at August 23, 2012 at 1:11 pm.
I am writing to say I would regret any reduction in the posts from Leif Svalgaard.
I do not know Leif Svalgaard. I have never met him and I have had no contact with him except for his comments on WUWT. But his posts show he is very knowledgeable on solar matters.
Others have different views on solar matters than Lief but he and they defend their views strongly.
I know little (almost nothing) about solar matters so I learn from the debates between people who do know about them. Hence, I want as many contributions as possible from all those who do know about them. And I want to learn from their disagreements about them.
Richard
If you want my opinion, it’s a lot of hot wind from this Sirocko fellow…
(I know I thought someone would have done it before…)
Of course the sun influences winters: Lockwood found that in SE England and now it is documented for the Rhine river between Mayence and Coblenz. We are not entirely sure though HOW it can proceed so selectively on a meteorological basis… /sarc
If you show the Figures, could you please add the Captions? Thanks. It clarifies for the lazy ones what’s been shown.
Central Europe is climatically unusual and probably unique in the world, because winter isotherms run north-south. Temperatures are determined by what direction the wind is from, and proximity to the Atlantic Ocean and central Eurasia.
It’s not clear to me why the low point of a solar cycle would cause a blocking high over Scandinavia resulting in easterly winds over Central Europe, but it does seem the likeliest explanation..
Leif Svalgaard says:
August 23, 2012 at 1:42 pm
Come on, Leif, have you no sense of humor?
“Are you (sic) comments that laughable?”
Well, I guess I have my answer. Lighten up, you’ll live longer. And there’s plenty of data & numbers on that. People might even take you more seriously.
You always have to love these papers about winter and cold air citing pressure data at 500hPa, that is well above the thickness of the variety of MPHs air masses that can create the surface winter conditions… This paper I bet must reference Cattiaux et al. 2010 that used the same trick to compare surface temperatures and the same high level pressure field between a recent cold winter and the 1962 winter.
The goal of these is to explain why CAGW is still going on despite ominous signs of cooling. Cattiaux et al. 2010 was blunt about this goal and the ubiquitous Jouzel was all too happy to use this everytime a cold winter was derailing the global warming predictions…
Leif Svalgaard says:
August 23, 2012 at 9:49 am
When one points out that a correlation between solar activity and weather/climate is poor, there is a persistent chorus of people crying “yeah, but you must take into account the lags in the system caused by the thermal inertia of the oceans”. Where is that lag here?
Thermal systems have indeed lag because of heat capacity. As already said this is about air circulation and redistributing cold and warm air; not heating of the air. Air circulation has very little lag time. From experience in flying a glider. Thermal uprising of air starts the moment the sun breaks trough the clouds on a concrete spot and stops the moment the sun leaves the spot. The lag is minimal and it only take a little difference in pressure or density to start an air flow.
Leif Svalgaard says:
August 23, 2012 at 11:36 am
MarkW says:
August 23, 2012 at 11:22 am
If the earth is indeed warming, then such freezings should have become more rare, if not disappeared altogether in the last 50 to 100 years.
And yet, they haven’t.
There hasn’t been any since 1963…, so they have become more rare.
A lot of powerplants, heavy industry (steel, chamical industry,…) are dumping enormous amounts of energy in the river. It thus not surprize me that it didn’t freeze over since 1963. Here in Belgium they ask powerplants to dump more heat into the canals to keep them ice free or at least keep the thickness of the ice limited in strong winters so shipping can proceed. I can imagine that if the Rhine treatens to freeze the German government will ask the companies to dump more heat so shipping can go on.
And then a climate scientist comes along,… and blaims it on global warming.
Jim G says:
August 23, 2012 at 2:11 pm
People might even take you more seriously.
I personally take people seriously when they present comments that are on topic, based on knowledge, physically plausible, and free from comments on other people’s character, but I guess we have different standards…
Pamela Gray says:
August 23, 2012 at 11:10 am
Just consider the blocking high over Russia. Think of the joules it took to create that high and then leave it in place (keep it a stable high pressure system, set up weak on-coming weather systems that go around it, and put in place down-stream systems strong enough to block the high from moving along).
——————————-
You assume that extra energy is necessary.Actually blocking highs indicate less energy in the system.
The jetstream is generated by the interaction between the SW winds from the Southern side of the Polar Front meeting the NW winds from the Arctic. When the temperature gradient across the Polar Front is large, the jetstream is energetic and tends to flow straight. Any perturbtions propogate rapidly along the stream and its position varies quickly in response.
When the temperature gradient is small, as it is at present, the jetstream is less energetic. It tends to vary more in latitude and respond less to perturbation.
By analogy to a river an energetic jetstream is like a mountain river. The large gradient gives it a lot of energy and it carves a straight bed. Once the river reaches the coastal plain it flows slowly down a gentle gradient and large meanders form.
This year the low energy jetstream has tended to trap areas of high or low pressure in place for long periods, hence the high temperatures due to the blocking high in the US and the cold, wet Summer in the UK.
As Dr. S. keeps pointing out, the TSI is not changing enough to explain extent of the climate oscillations amplitude, and it does not need to, any unstable system is vulnerable to oscillations if exposed to a steady periodic excitation. It could be as simple system as a pendulum or as complex as the ocean-atmospheric pressure coupling as shown here using North Atlantic data.
http://www.vukcevic.talktalk.net/NAO-SST-ea.htm
– NAO = North Atlantic Oscillation – atmospheric pressure
– AMO = Atlantic Multidecadal Oscillation – Sea surface temperature.
I favor capacitor (ocean) – inductor (atmosphere) analogy; mass-spring analogy is also transmutable into the ocean-atmosphere oscillation supposition.
As one piece of evidence of that warming, the Rhine River has not frozen over since 1963. Sirocko said such warming results, in part, from climate change.
Well it would have nothing to do with more river traffic with engines cooled by river water that is then returned hot to the river would it. Or with more buildings and other developments with UHI and warm drainage outfalls into the river.
No no nothing like that – the Rhine must be kept warm by carbon dioxide… using the Trenberth missing heat method. /sarc
Leif Svalgaard says:
August 23, 2012 at 2:30 pm
“comments that are on topic”. The topic was thermal lag. So iwill go back there in plainer language for you, why is it not possible for thermal lag to show in the data during one time period and not in another when there are potential exogenous variables intervening in one period and not in another? Do you know for a fact that no other variables were involved in each period? Weasel words are not necessary as all of the facts are not, as they cannot be, known, so such a comment is not necessary nor constructive to the dialog. Not everything is a straight line or even curvilinear correlation due to the chaotic, multivariate, intercorrelated nature of many climate variables.
Bert Lemmens says:
August 23, 2012 at 2:28 pm
Thermal systems have indeed lag because of heat capacity. As already said this is about air circulation and redistributing cold and warm air; not heating of the air.
Not really. Those very cold winters are caused by blocking of air masses [and high pressure over Russia]. Those are hard to change and are not just the sun disappearing behind a cloud..
Jim G says:
August 23, 2012 at 3:01 pm
Weasel words are not necessary as all of the facts are not, as they cannot be, known, so such a comment is not necessary nor constructive to the dialog.
This is trivially true of any dialog, so constructive dialogs are impossible, to wit: your comments.