Solar Cycle 24 Length and Its Consequences

Guest post by David Archibald

Solar Cycle 24 is now three years old and predictions of the date of solar maximum have settled upon mid-2013. For example, Jan Janssens has produced this graph predicting the month of maximum in mid-2013, which is 54 months after the Solar Cycle 23/24 minimum in December 2008:

image

For those of us who wish to predict climate, the most important solar cycle attribute is solar cycle length. Most of the curve-fitting exercises such as NASA’s place the next minimum between 2020 and 2022 (eg: http://wattsupwiththat.com/2011/11/06/nasas-november-solar-prediction/). Solar minimum in December 2022 would make Solar Cycle 24 fourteen years long, which in turn would make the climate of the mid-latitudes over Solar Cycle 25 about 1.0°C colder than the climate over Solar Cycle 24.

image

Curve-fitting leaves a lot to be desired. Even late in the progression of Solar Cycle 23, the curve fitters in NASA had poor predictive ability.

Examination of Altrock’s green corona emissions plot from mid-2011 suggests that a new predictive tool is available to us. The original is available here:

http://www.boulder.swri.edu/~deforest/SPD-sunspot-release/6_altrock_rttp.pdf

This is my annotated version:

image

Altrock had observed that solar maximum occurs when the “rush to the poles” reaches 76°. The magnetic poles of the Sun reverse at solar maximum, which is also considered to be the beginning of the new extended solar cycle.

We also observe that solar minimum for the last four minima has occurred when emissions are exhausted at 10°. The latitude of 10° is shown as the red line on the diagramme. Further to that, the last two solar cycles show that the month of minimum can be predicted by drawing a line between solar maximum (the point at which the rush to the poles intersects 76°) and the point of exhaustion at 10°. The bulk of activity is bounded by this line.

Altrock has noted that the “rush to the poles” in Solar Cycle 24 is much weaker and much slower than in previous solar cycles. The line he has drawn intersects 76° in mid-2013, consistent with other predictions of Solar Cycle 24 maximum.

The shape of the emission regions also suggests that Solar Cycle 24 will be quite extended. The blue bounding line from the Solar Cycle 23 maximum intersects 10° latitude in 2026, making Solar Cycle 24 eighteen years long.

That would be an exceptionally long solar cycle. The most recent cycle that neared that length was the seventeen years from the maximum of Solar Cycle 4 to the maximum of Solar Cycle 5. Prior to that, the Maunder Minimum had some very long solar cycles as interpreted from C14 data:

image

It seems that the first solar cycle of the Maunder Minimum was also eighteen years long.

An eighteen year long Solar Cycle 24 would be very significant in that it would be five and a half years longer that Solar Cycle 23. With the solar cycle length/temperature relationship for the US-Canadian border being 0.7°C for each year of solar cycle length, a further cooling of 3.8°C is in train for next decade. The evolution of Altrock’s green corona emissions diagramme as a predictive tool will be followed with some interest.

Back to the subject of curve-fitting, it may be still too early to call Solar Cycle 24 using that technique. The following graph shows the raw monthly data for sunspot number amplitude for Solar Cycles 5 and 6 (the Dalton Minimum) with Solar Cycle 24 to date aligned on the month of minimum. Solar Cycle 5 took about four years to get going before it had a sudden burst, and then died off over the following ten years. It is still a bit too early to be certain about how Solar Cycle 24 will shape up.

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The world temperatures appear to be driven by the AMO (North Atlantic SST), which has very little to do with the solar cycles. The AMO originates in the sub-polar area where the solar effect is greatly reduced due to the low obliquity of incidence.
http://www.vukcevic.talktalk.net/GT-AMO.htm
(see also spectral response in the above link)
No one would be happier than myself, if it can be shown that the climate oscillations are driven by changes in the TSI due to the sunspot cycles, since the formula extrapolation for the SC24 has proven itself to be (up to date) the most accurate sunspot cycle prediction tool:
http://www.vukcevic.talktalk.net/NFC7a.htm

Rosco

Wow – I have the first comment.
Exciting times ahead with many different solar scientists from different backgrounds writing similar scenarios for the next few solar cycles.
There seems to be general agreement that solar cycles are heading towards reduced solar activity – the only disagreement is over whether “greenhouse gases” will generate the reduced energy needed to stave off global cooling and keep us toasty warm.

Rosco

Correction – he who hesitates reading is lost.

George E. Smith;

Dave,
I need to read your essay in detail, but already I found a gee whizz.
I had always just assumed (and you know where that gets us) that the solar magnetic reversal took place at the solar minimum; when there weren’t a lot of spots.
But you say that reversal occurs at the solar maximum. I’m puzzled that Dr Leif Svalgaard has never mentioned that fact.
So how does that work for say a single sun spot; they just up and reverse polarity in mid stride ?
Or does the polarity of an existing spot not reverse; but new ones appear with opposite polarity at the time of maximum?
Well we learn something new every day.
Thanks
George

A physicist

Poking around a bit, I found an on-line manuscript by one David Archibald:

Solar Cycle 24: Implications for the United States
David Archibald
International Conference on Climate Change
March, 2008
Can we expect relationships between the Sun’s activity and climate, that we can
see in data going back several hundred years, to continue for at least another 20 years?
With absolute certainty.
… 2008 is the tenth anniversary of the recent peak on global temperature in 1998. The world
has been cooling at 0.06 degrees per annum since then. My prediction is that this rate of
cooling will accelerate to 0.2 degrees per annum following the month of solar minimum
sometime in 2009.

David, it’s now been almost four years since your March 2008 predictions … is there (as yet) any evidence in the global temperature record that those predictions were correct?
Heck, even here on WUWT, Bob Tisdale has substantially replicated the Foster & Rahmstorf (2011) finding that when cyclic trends are subtracted, the underlying trend is strikingly warming.
As everyone knows, North America is now experiencing one of its warmest, most snow-free winters in history … wholly contrary to your 2008 prediction. How many more months-and-years of warming will be required to convince you that sunspot-driven climate models perhaps are … well … just plain wrong?

ferdberple

Rosco says:
January 8, 2012 at 12:24 pm
whether “greenhouse gases” will generate the reduced energy needed to stave off global cooling and keep us toasty warm.
No question about it. The IPCC tells us in no uncertain terms, echoed by solar scientists themselves, that the sun is much to constant to influence climate. Humans are driving climate change. The Minoan caused the Minoan Optimum. The Romans caused the Roman Optimum. The fall of Rome caused the Dark Ages. The Vikings caused the Medieval Optimum and the Renaissance caused the Little Ice Age. Now the Industrial Age has caused the Modern Optimum.
We know that it is CO2 that keeps us warm because every time the planet warms CO2 levels increase. Climate Science is certain. The Sun has nothing to do with it.

Ed Caryl

A physicist,
That’s weather, not climate. The snow cover in Asia is higher than last year. Check here:
http://www.climate4you.com/SnowCover.htm
The charts for Greenland are interesting.

J Martin

To A physicist.
What planet are you on ?

William Abbott

The anecdotal evidence that the northern hemisphere was exceptionally cold during the Maunder Minimum and Dalton Minimum is strong. If the sun enters another Grand Minima – we will likely have similar profound cooling. We might not be able to explain the mechanism now. Our guesses might be wrong – but I’m assuming another strong correlation between a long quiescent sun and colder weather.

ferdberple

A physicist says:
January 8, 2012 at 1:13 pm
Foster & Rahmstorf (2011) finding that when cyclic trends are subtracted,
Nope. F&R (2011) subtracted the linear trend, not the cyclic trend. What they showed is the temperature is strongly correlated with time. The more time you have, the higher the temperature.
This is about what you would expect statistically. For example, say you started recording the temperature outside today. The longer you recorded the temperature, the more likely you would see a new maximum and minimum temperature. Records are meant to be broken.
The same thing with climate. We’ve only been keeping thermometer records for a short while in climate terms. The longer you keep records, the more likely you are at some point in time to set new records. Thus temperature records correlate strongly with time.

Ferd. You do indeed seem very certain of your claims that “every time the planet warms CO2 levels increase” – so do they decrease as a result of it cooling – such as just after 1945? (LOL) Maybe you could answer with similar certainty these four questions …
(1) When the refective (mirror-like) internal surface of a vacuum flask reflects radiation back into the coffee the coffee does not get any hotter – true / false ?
(2) If you hold a mirror over a batch of earth (which is radiating) at night so that the mirror reflects that radiation back to the patch it does not get any hotter, just like the coffee – true or false?
(3) When carbon dioxide captures radiation from the surface and then re-emits it back again it is acting rather like a mirror because the radiation going back has no more energy than that which it captured – true or false?
(4) Hence, when such back radiation meets the surface it does not warm the surface – true or false?

J Martin

A 3.8 C temperature drop. Correct me if I’m wrong, but that’s Maunder minimum territory and all that that implies. As the UK imports nearly half it’s food (40% in 2009) the consequences of such a drop could prove interesting.
Time for the UK to invade a defenceless country perhaps, Australia looks like a good bet.

A causal connection between low sunspot activity and cold winters emerged recently in data from NASA’s Solar Radiation and Climate Experiment which shows that solar UV output is more variable over the course of the solar cycle than scientists had previously thought. See: October 9, 2011 Nature Geoscience . During one 30-year period within the Maunder Minimum, astronomers observed only about 50 sunspots, as opposed to a more typical 40,000-50,000 spots in modern times.

ferdberple

Ed Caryl says:
January 8, 2012 at 1:43 pm
A physicist,
That’s weather, not climate.
Ed, how can you say that! Every climate Scientists knows that when temperatures go up it is climate. Only when they go down is it weather. A physicist tells us that temperatures are going up, so therefore it is climate by definition.
Are we clear on this? Increasing temperatures are climate. Decreasing temperatures are weather. Any change in the increase in temperature is therefore Climate Change. Any change in the decrease in temperatures is Climate Disruption – it is a disruption in climate change.
To summarize:
increase T = climate
decrease T = weather
delta increase T = climate change
delta decrease T = climate disruption.

Rhoda Ramirez

Ferd, I like your style.
Dieta, I don’t see a causal connection there. Perhaps the cite you mentioned (but didn’t provide a link to) has it. Although I must admit that I feel intuitively that there must be a relationship between solar out put and our weather, the old correlation doesn’t imply causation rubric still applies.

BarryW

A physicist,
And the Rockies are experiencing much higher than normal cover

and Alaska is freezing it’s butt off:

Records are being broken or challenged by blizzards in Prince William Sound and cold temperatures in Nome.
A glut of snow during the first week of 2012 choked roads in Valdez and Cordova and collapsed warehouse roofs in both of the Prince William Sound cities, which were still digging out Friday as the snowfall threatened to continue into the weekend.


Cherry picking is fun isn’t it?

ferdberple

Doug Cotton says:
January 8, 2012 at 1:57 pm
Ferd. You do indeed seem very certain of your claims that “every time the planet warms CO2 levels increase”
We know it is true because Al Gore says it is true and he won the Noble Prize for saying so. All the climate scientists with the IPCC agree with him and they won a Nobel Prize for saying so.
Al Gore is perhaps the finest example of the quality of Climate Science in the world, which is why he was personally awarded the Nobel Prize. The other climate scientists, well they just don’t measure up as compared to Al Gore, which is why none of them received the Nobel personally.

Jimbo

A physicist says:
January 8, 2012 at 1:13 pm
North America is now experiencing one of its warmest, most snow-free winters in history

What did you say when it experienced Snowmageddon a few years back?
Anyway, R. Gates has told us that we get more snow in a warmer climate. So, which is it? More snow, less snow, average snow. Cherry picked snow.

Otter

A Fizz~’As everyone knows, North America is now experiencing one of its warmest, most snow-free winters in history ‘
Funny thing. A friend of mine in Missouri, was commenting on the mild winter down his way, so I went looking in the weather archives for his city (Springfield). Now, I don’t recall the exact year I happened across (I picked random years from 1946 onward, which is the year which the Farmer’s Alamanac appears to start records from for that area).
One year in particular- chosen at random- stood out: I believe it was 1966. And wouldn’t you know it! It was a HELL of a lot warmer that winter, than this one!
And the US has gotten warmer, since? Doesn’t seem to square up, does it, Fizz?

James Fosser

J Martin says:
January 8, 2012 at 2:05 pm Sir or Madam. You say time for the UK to invade a defenceless country such as Australia. You should advise the UK not to try that, as Australia is building up all of its forces (and poaching thousands of redundant sailors from the UK) whilst the UK is down now to a few small ships in its navy and is issuing redundancy notices to thousands of soldiers and members of its dwindling air force.

Otter

And now, if I may, a question for intelligent people on this article:
Volcanic and seismic activity seems to have ramped up lately. I am curious if there is a relationship between the Sun’s geomagnetic activity (since it has dropped quite a bit), and geologic activity on the Earth? Main reason I ask this is because there was quite a bit of volanic activity coming out of the LIA (and likely, going into it). I had seen comments over the years, that volcanic activity had dropped off as the sun’s activity increased. I have to think the connection is more than just incidental.

A physicist

David [Archibald], I’m just pointing out how odd it is that your WUST post never references your own 2008 prediction that the Earth should already be cooling at 0.2 degrees per year … and neither does your post comment upon the striking fact that of five independent raw temperature data sets shown in Figure 1 of WUWT’s much discussed and carefully verified Foster & Rahmstorf (2011) analysis … all five data sets show a pronounced rise in global temperature in 2008-2009-2010 (as anyone can check for themselves, thanks to a WUWT post by Bob Tisdale).
WUWT, indeed?

ferdberple

dieta says:
January 8, 2012 at 2:08 pm
NASA’s Solar Radiation and Climate Experiment which shows that solar UV output is more variable over the course of the solar cycle than scientists had previously thought.
Egads man, what were you thinking. Now we will have Leif all over us. Please observe rule #1. The sun absolutely and positively cannot influence climate until solar scientists have proven it can influence climate. Until then the null hypothesis rules out any possibility.

ferdberple

Otter says:
January 8, 2012 at 2:32 pm
I had seen comments over the years, that volcanic activity had dropped off as the sun’s activity increased. I have to think the connection is more than just incidental.
There is considerable evidence that seismic activity peaks when the planets and sun are aligned. There is considerable evidence that planetary alignment influences solar activity.
The problem is that this question is rarely studied. One of the most damning insults in science, especially in the US, is to accuse a fellow scientists of engaging in Astrology. Thus, a decision to investigate can be career ending.

ferdberple

James Fosser says:
January 8, 2012 at 2:31 pm
You say time for the UK to invade Australia.
The UK has a simple plan to get rid of their surplus armed forces. They will invade disguised as Indonesians. No weapons required, free room and board when they arrive. No end of volunteers looking to escape the UK climate of horrible winters and miserable summers.

Jimbo

A physicist says:
January 8, 2012 at 1:13 pm
As everyone knows, North America is now experiencing one of its warmest, most snow-free winters in history

In history!!! Do you mean since the start of the thermometer record? Anyway, here is some more cherry picked points as two can play your game. ;>)

Kenya 5 January, 2012
“We are looking at about 20 million kg of green leaf we have lost, whose value is in the region of Sh1 billion ($11.4 million),” Njagi said, adding that this was the worst ever case of frost to hit the country.
http://www.standardmedia.co.ke/InsidePage.php?id=2000049510&cid=14&j=&m=&d=

Cold-stunned turtles washing ashore in North Carolina
http://www.starnewsonline.com/article/20120105/ARTICLES/120109857/-1/news38?p=all&tc=pgall

All caused by Global Warming Climate Disruptivity.

Camburn

As far the the warm NH goes, Dr. Masters seems to have this one right.
Note that he talks about the sun effect on jet streams etc:
http://www.wunderground.com/blog/JeffMasters/article.html

“And the Rockies are experiencing much higher than normal cover”
We currently have a persistent ridge of high pressure that is pushing storms North over California. You can see it in action here:
http://www.ssd.noaa.gov/goes/west/nepac/flash-wv.html
The storms are being pushed up into British Columbia and then are drawn back down into Montana or head East across Canada. Most of the weather in the rest of the US is coming from a weaker Southern jet. This is an unusual pattern not generally associated with either La Nina or El Nino but that persistent high pressure has been sitting there for over a month blocking storms from the Sierra Nevada and pushing the jet far North of its usual track for this time of year.

King of Cool

J Martin says:
January 8, 2012 at 2:05 pm
Time for the UK to invade a defenceless country perhaps, Australia looks like a good bet.

You may find the Chinese got there first:
http://www.abc.net.au/news/2011-08-15/china-looks-for-wa-agriculture-land/2840486
http://www.theaustralian.com.au/news/nation/chinese-mine-giant-snaps-up-43-nsw-farms/story-e6frg6nf-1226082387428
(Some-one mention the warm N America winter? And on another thread, in London?)
Even though SE Australia experienced the coldest start to summer for 60 years the Chinese may prefer that to what they are getting:
http://202.108.9.138/news.jsp?fileId=126867
Cold cherries in Russia too?
http://english.ruvr.ru/2011/12/24/62818109.html

nc

A physicist: where are the 50 million or so climate refuges?

u.k.(us)

Possibly, the most amazing part of this whole argument, is how many people believe their politicians can control the weather.

Phil's Dad

J Martin says: (January 8, 2012 at 2:05 pm) “… As the UK imports nearly half it’s food (40% in 2009) the consequences of such a drop could prove interesting.”

Intuitively a country that already has in place the mechanism and means to import a substantial proportion of its food is better placed to weather (pun intended) climate disruption, as it already has a spread portfolio of sources.
As for the UK invading Australia – that is sooo last century.

J Martin

To King of Cool
If you allow the Chinese to buy a significant proportion of your farms. What happens when Australia needs the food that those farms produce and declare that the food can no longer be exported to it Chinese owners in China.
The result will be invasion by China to secure it’s property rights and food supply. Australia is going down a very dangerous path.

View from the Solent

“James Fosser says:
January 8, 2012 at 2:31 pm
J Martin says:
January 8, 2012 at 2:05 pm Sir or Madam. You say time for the UK to invade a defenceless country such as Australia. You should advise the UK not to try that, as Australia is building up all of its forces (and poaching thousands of redundant sailors from the UK) whilst the UK is down now to a few small ships in its navy and is issuing redundancy notices to thousands of soldiers and members of its dwindling air force.”
==============================================================
Indeed! Given a few more years the Royal Navy will consist of a few rowing boats on Canoe Lake in Portsmouth, the home of the Royal Navy. (but Nelson’s HMS Victory is undergoing a refit, so all is not lost)

A physicist

BarryW says: Cherry picking is fun isn’t it?

Yah, sure, you betcha! 🙂
BarryW, the NOAA State of the Climate summaries (both national and global) are the place to go for *all* the data … and there’s no confirmation in that data for David Archibald’s 2008 predictions.
David ought at least to comment on that.

J Martin

At the risk of turning into a sort of R Gates and taking over a thread without regard to the actual article, in this case by David Archibald;
If we see a repeat of the Maunder minimum as suggested in the article, we know that the effects of that were global, though with the severest effects in the Northern hemisphere. A possible result is that countries which currently produce and export an excess may no longer be able to do so and the UK may find itself unable to source the same volume of food imports it currently does, whilst at the same time seeing a potentially serious reduction in local food production due to the 4 degree C drop in temperatures.
Canada could see an end to all wheat production. The US should be OK since they just have to stop feeding corn to cars. The middle east will likely destabilise totally as they are too dependant on imports. Russian and Ukrainian grain surpluses have already been shown to be vulnerable just last year (?). Last time round the French struggled to feed their then population and had a little uprising. In the UK in the summer some of the population had a dry run at the uprising food riot thing when they went flat screen TV shopping without money.
I reckon the government planners who are currently planning on “a warming World” (idiots) will need to switch to planning for “a cooling World”. Lets hope they come to their senses in time, because a modern Maunder minimum may not prove easy to beat, despite our modern technology. We do have considerable advantages over farmers from the 1600s, hot air grain drying machines, bio engineering of plants, poly tunnels, etc etc. But has anyone sat down and worked out if it will be enough ?

I thought it interesting when I read a story that noted a destroyer as the UK’s “mightiest” warship.
http://www.telegraph.co.uk/news/uknews/defence/8997956/Royal-Navy-sends-its-mightiest-ship-to-take-on-the-Iranian-show-of-force-in-the-Gulf.html

HADCRUT3 – Global Temperature Record:
The time series shows the combined global land and marine surface temperature record from 1850 to 2010. It shows no additional warming since 2003.
See http://www.cru.uea.ac.uk/cru/info/warming/
The NCDC – Global Surface Temperature Anomalies database shows a similar flat trend from 2003 to 2010 (16-May-2011, NOAA, National Climatic Data Center).
See http://lwf.ncdc.noaa.gov/sotc/service/global/global-land-ocean-mntp-anom/201001-201012.gif
The annual mean anomalies Hadley Centre Central England Temperature (HadCET) dataset shows a decline of 0.5°C from 2001 to 2011.
See http://www.metoffice.gov.uk/hadobs/hadcet/
Climate disruption or global cooling?

ChrisM

Rather than just accuse “A physiscist” of cherrypicking, how hoes he reconcile his comment that:
Heck, even here on WUWT, Bob Tisdale has substantially replicated the Foster & Rahmstorf (2011) finding that when cyclic trends are subtracted, the underlying trend is strikingly warming.
with the following closing comment of Bob’s:
The assumption made by Foster and Rahmstorf (2011) that a linear trend provides an approximate “global warming” signal was shown to be erroneous using Sea Surface Temperature data. When broken down into two logical subsets of the East Pacific and the Atlantic-Indian-West Pacific Oceans, Satellite-era Sea Surface Temperature data shows no evidence of an anthropogenic global warming signal. It only shows upward shifts associated with strong ENSO events. This would seem to complicate any attempt to justify the inclusion of the linear trend to reverse the sign of the solar adjustment.
One can be charitable and suggest that he didn’t actually read the full article or maybe he just didn’t understand it?

J Martin

To A physicist
NOAA. That’s the organisation that has just been caught systematically adjusting historic data every month for a year. Meaning that nothing NOAA say or publish can ever be trusted again.
http://sppiblog.org/news/noaa-climate-scientists-gone-wild-bizarro-temperature-data-fabrication-continues
http://www.c3headlines.com/2011/12/science-by-lubchencos-noaa-fake-global-warming-by-changing-historical-temperature-data.html

Sean Peake

Hey, A Physicist is back. Must have gotten a new shipment of weed.

Phil's Dad

On reflection gentlemen there would be a bit of a problem with Australia and the UK opposing each other in a military conflict.
Here is what all Australian military have signed up to;
“I, (insert full name of person) swear that I will well and truly serve Her Majesty Queen Elizabeth the Second, Her Heirs and Successors according to law, as a member of the (insert Australian Navy, Australian Army, or Australian Air Force) for the period of (number of years), and any extensions of that period, or until retiring age, and that I will resist her enemies and faithfully discharge my duty according to law.”

Steve M. from TN

nc says:
January 8, 2012 at 3:10 pm
A physicist where are the 50 million or so climate refuges?
More importantly, what have we done with the 4.5 billion dead?

Richard Sharpe

nc says on January 8, 2012 at 3:10 pm

A physicist where are the 50 million or so climate refuges?

They’re being hidden by the evil Big Oil, Big Coal and Big Gas companies so that the world will not realize that solar panels and windmills are the one true path of enlightenment.

James Allison

A physicist says:
January 8, 2012 at 1:13 pm
2 Years – oh maybe 3 years ago – Fizz this is a joke right?

David Archibald

George E. Smith; says:
January 8, 2012 at 1:11 pm
George, love your work. Here’s a link on magnetic reversal at maximum:
http://www.sp.ph.ic.ac.uk/~forsyth/reversal/

BarryW

A physicist
Didn’t get the html right last time but here is my reference for the change in snow cover:
snow cover departure from normal
Or don’t you think Rutgers or Hadcrut are reputable enough?

BarryW

Let’s try the Hadcrut reference again
Global Temps

James of the West

It’s too early to say for sure that the world will cool by x degrees due to the current solar cycle, if a prediction is made it will just be a guess based on curve fitting from previous temperature proxies and anecdotal weather event reports from history as we try to guess what the solar cycle is doing.
Maybe it will cool in the next decade who knows. Now that we have reasonable (but not perfect) temperature measurement data we will learn how the planet responds to the solar cycle in play. Lets not make the mistake made by warmists with arm flailing predictions of future climate based on very limited understanding – lets see what it actually does and try to gain insight. Also please dont call others with different opinions idiots etc, just stick to discussing the ideas and data.
One thing is for certain warming has plateaued for the last decade and recent la nina conditions seem fairly persistent.

David Archibald

A physicist says:
January 8, 2012 at 1:13 pm
To the right of your comment I see the World Climate Widget, which says that the planet is 0.12 degrees warmer than it was thirty years ago. This is despite the fact that the Sun was more active in the second half of the 20th Century than it had been in the previous 8,000 years. For the record, atmospheric CO2 content has gone up 20% over that same period with no effect, except for a bigger biomass. In the meantime, three distinguished Norwegian scientists from the hard sciences have confirmed my methodology. Perhaps you saw this post:
http://wattsupwiththat.com/2011/12/16/polar-amplification-works-both-ways/
Northern Europe has already experienced the predicted decline under the model.