Guest essay by David Archibald
Wiggle-matching has been used by the best. Hubert Lamb, considered to be the most meticulous climatologist of all time, used wiggle-matching in this wind data graph he published in 1988:
He had plotted up 600 years of wind data at London, noted a 200 year periodicity and copied the line 200 years to the right to make a forecast.
One of the puzzles of the last 300 years of climate is the temperature drop of 1740. It came out of the blue after a number of warm years in the 1730s. There is nothing in the Be10 record or the volcanic record to suggest a cause.
It came a couple of years after the peak of a fairly strong solar cycle. The event of 1740 attracted the attention of Briffa and Jones in their 2006 paper “Unusual Climate in Northwest Europe During the Period 1730 to 1745 Based on Instrumental and Documentary Data”. From the abstract of that paper,” This study focuses on one of the most interesting times of the early instrumental period in northwest Europe (from 1730–1745) attempting to place the extremely cold year of 1740 and the unusual warmth of the 1730s decade in a longer context.” The only conclusion that they came to was climate might vary more than is commonly accepted.
So what does that period up to 1740 wiggle-match with? It matches with the warmth of the last 30 years:
The graph above shows the Central England Temperature (CET) record from 1703 to 1745 as the blue line. Plotted on it is the CET record from 1978 to 2012. Normally when you align 34 year lengths of temperature records you don’t get any correlation. The correlation on this particular matchup is 0.112. The statisticians amongst us can argue over whether or not anything can be read into that. If something can be read into it, we only have to wait two years to experience the consequences. The spike down is also prominent in the de Bilt record:
Brrrr! Not what I would prefer, and certainly more dangerous than warming.
Could of had something to do with the PDO and AMO.
Well even if we don’t understand the causes, and even if we have to suffer a debilitating cold spell..it would at least kill off the CAGW nonsense….you would think?
Hopefully confined to the Northern Hemisphere like “global” warming…
“The correlation on this particular matchup is 0.112.”
I presume you mean r²? Sorry, I’m not impressed. Wiggle-matching is interesting, and a way to look at data to spot possible relationships or mechanisms, but that’s about it. I’d say the relationship here, if any, is very tenuous, with an r² of less than 0.4.
The UK Met recently called an emergency meeting with the world’s top climate scientists to discuss how melting polar ice is radically altering that country’s weather. A permanent blocking high pressure system has formed over Greenland. This high has, effectively, caused the Arctic to invade the UK with increasing ferocity. The state is now so extreme that the Met is calling a meeting of the world’s climate experts to discuss what the future may hold.
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Yes Dorothy, it really IS climate change
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Dr. Slingo, Britain’s top climate scientist notes how persistent high pressure systems are blocking the polar wind pattern from moving. What this means is that the weather simply cannot change. Increasingly, the UK has become a part of the Arctic. Slingo noted to ITV News:
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Its called a “blocking pattern”
http://en.wikipedia.org/wiki/Block_(meteorology)
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If this is how climate change could manifest itself, then we need to understand that as a matter of urgency.
http://robertscribbler.wordpress.com/2013/04/12/human-climate-change-is-wrecking-the-jet-stream-uk-met-office-calls-emergency-meeting/
———————
Absolutely no one can deny that the weather is changing in the extreme. Keep your eyes on the arctic.
More research on the Greenland blocking high
http://www.washingtonpost.com/blogs/capital-weather-gang/wp/2013/03/21/record-blocking-patterns-fueling-extreme-washington-d-c-march-weather/
As stated, a blocking pattern like this ranks among the strongest ever; to further illustrate that fact, I have plotted the 500 mb height composite anomaly from the 12 separate dates on which the AO plunged to its most negative values in recorded history. The composite, shown below, reveals positive anomalies in excess of 350m near Greenland – neatly matching the current block’s intensity.
One more remarkable aspect of this major league block: observations over Greenland are threatening to break the worldwide record for highest barometric pressure of 1083.3 mb, set on Dec. 31, 1968 in Siberia. NCEP’s Ocean Prediction Center analyzed the surface map (from Tuesday night) below, which features a high pressure center of at least 1074 mb over Greenland.
jai mitchell says:
“Keep your eyes on the arctic.”
What mitchell really means is, ‘Pay no attention to the Antarctic’, because the Antarctic falsifies everything mitchell is saying: Total global ice cover is increasing. Long term polar ice is rising [the red line]. But mitchell ignores facts that do not support his climate alarmist world view.
There is a clear cycle of around 208 years in a number of solar and climate proxies as well as in the solar cycle. Please see these links:
http://cyclesresearchinstitute.wordpress.com/2010/06/27/cycles-in-sunspot-number-reconstruction-for-11000-years/
http://cyclesresearchinstitute.wordpress.com/2011/07/13/analysis-of-be10-records-as-a-solar-irradiance-proxy/
http://cyclesresearchinstitute.wordpress.com/2012/11/13/sunspot-number-reconstruction-by-leif-svalgaard-and-proxy-cycles-of-104-and-208-years/
jai mitchell says:
June 18, 2013 at 9:25 pm
So its the melting icecap thats causing the blocking high is it?
Sigh! IF it does head that way, standbye for the rush to any form of nuclear energy plant that can be built ASAP, under the new post Obama World Energy Emergency Management plan, renamed as World Obama Management Energy Nuclear plan WOMEN Plan ,,,[no gender insult intended!!], just good warm world housekeeping..
jai mitchell says:
June 18, 2013 at 9:30 pm
A blocking high possibly caused by the Ap Index or the EUV being very week.
David, you missed the most interesting part. What has the frequency of the southwest wind at London done in the past 20 years?
I would guess that, given the low temperature crisis that jai mitchell is worried about, that we might just be at the nadir on the graph predicted by Lamb. Southwest wind should tend to bring balmy air to Britain — and thus a low frequency of southwest winds should correlate to lower temperatures.
If Lamb’s prediction is right, then the crisis will start to abate soon.
I continue to believe that kinetic energy should be a primary factor in the climate models. When conditions in the climate system are such that incoming solar radiation is efficiently converted to kinetic energy in the atmosphere, the remaining energy available for heat is lowered. Conversely, when conditions are not favorable to kinetic energy development the energy balance shifts to favor heating of the atmosphere and re radiation out into space.
I’ll spend the rest of my years trying to get a coherent hypothesis together and then discover I am completely wrong! That’s the beauty of science; it is a marvelous journey that is never “settled”.
jai mitchell says:
June 18, 2013 at 9:30 pm
More research on the Greenland blocking high
Does that have anything to do with the extremely warm temps in Alaska right now or is that a separate phenomenon. I’ve heard reports of temps ranging from 82 – 98 degrees across the state after having unusually cold temps until just recently.
I often wonder on which planet some internet commenters reside. This thread has me wondering the same. But okay, sure, we’ll keep our eyes on the Arctic. Because, you know, with everything else that’s been going on, somehow we forgot to look there. Right?
jai mitchell says:
June 18, 2013 at 9:25 pm
“The state is now so extreme that the Met is calling a meeting of the world’s climate experts to discuss what the future may hold.”
Why is the Met calling this meeting? Clearly, the Met is at a loss as to what is going on or they would tell us what is going on. Are they looking for help? Seems unlikely because all the Met understands are their own computer models. Could it be that (1) they are attempting to change the topic from their own disastrous performance of recent years and (2) they are calling upon friends to help them recover from the implosion of their rationale for claims of CAGW, also known as creating a new consensus?
If the blocking high will be stuck there for years then England, parts of Europe, and parts of Asia face another Little Ice Age. Now what does AGW have to do with that? We cannot lower CO2 emissions dramatically enough to prevent such a Little Ice Age. Are you suggesting that the blocking high will remain in place until emissions are lowered dramatically? I think that you have pushed into an area of theory where even Alarmists fear to tread.
Is everyone watching how the climate alarmists are slowly turning themselves around.
Once was global warming (that stopped 17 or so years ago),
then climate change, (not much happening there, still up and down all over the place, is it has always been)
then extreme weather..(hurricanes etc mostly declining)…
. next step is global cooling…. just watch…. 🙂
Jai’s already on the march down that laneway !
> Southwest wind should tend to bring balmy air to Britain
Also, a large blocking high over Greenland should cause less southwest wind in London. This would be compatible with (but *not demand*) similar blocking high patterns 200 years ago. And 400 years ago. And so on.
“The only conclusion that they came to was climate might vary more than is commonly accepted.”
If this was just for one year, 1740, then “climate” may be the wrong word. So, substitute the word “weather.” The real issue is who gets to say what is “commonly accepted”? They didn’t ask me. I’m pretty convinced that both weather and climate vary considerably. If it is very cold or very warm in 2 years, I won’t be surprised or concerned. Interested, yes.
How well does the 34-year CET record preceding the 1740 event correlate with random 34-year CET records (i.e. other than 1978 – 2012)?
Reblogged this on The Next Grand Minimum and commented:
This is an interesting observation that needs more study.
I think the correlation of the two graphs is coincidental and a micro ice age is unlikely.
In the UK we have had a succession of mild winters in the nineties and noughties, this has caused the more ill-informed climatologists to metaphorically run around in ever decreasing circles telling us we are all doomed! The last four winters have been colder than average, because that is what averages do! To demonstrate the ineptitude of these so called scientists, Slingo and co have called a meeting to discuss the current “extreme” weather and it’s relationship with AGW. Sorry to disappoint, but it is neither extreme nor AGW induced. No doubt they have come to the very opposite conclusion because although the science says “no”, their mantra says “yes”!
Jai,
To the best of my understanding melting ice would release enthalpy of fusion, warming the ocean and thereafter the atmosphere, causing low pressure, not high.
Have you ever watched the NOAA 12000m animation? Cooling and descending air is the definition of high pressure. It is the reason we have subtropical deserts. It is the reason we see high pressure anomalies throughout the Arctic these days. Shifting here and there, but very persistent overall. The high pressure does not result from the melting ice, it causes the ice to melt.
The science is simple and well understood. The optical properties of ice are surprisingly similar to water. UV goes into it as if it were butter. IR not much. Pretty much why it reads blue to us when backlit.
Try not to demonize change. The winds today are the winds of change, but they are the very same winds that have blown since time immemorial.
http://geosciencebigpicture.com/2013/04/14/something-in-us-loves-a-witch/
Air temps in the Arctic are lower than normal for this time of the year and may even stay as low as if not lower than 1993 and 1980, leading to a shorter melt season? Interested to hear what others may think about this.
http://ocean.dmi.dk/arctic/meant80n.uk.php
All due to CO2 of course, /sarc
It appears that we’re entering a 187 year solar cycle. It happens that after every 17 solar cycles, there is a particular Jovian planet conjunction and a consequent transfer of orbital momentum to the sun. The transfer of orbital momentum (and barycenter shift) perturbs the sun’s plasma and creates conditions of high solar activity (late 20th Century) followed by periods of abnormally low solar activity. Humans have seen this many times in the past, most recently during the Dalton (1790-1830) and Maunder (1645-1715) Minimums. Whether or not the abnormally cold conditions during the low solar activity periods are caused by low altitude clouds precipitated by cosmic rays and muons, the fact remains that we may be witnessing the start of our very own “Minimum”. From what I can gather, warming is preferable, not only from a comfort and energy preservation point of view, but also because dramatic cooling adversely affects the growing season and harvest production.
I have been dealing with the change in jet stream behaviour since 2008 having first noticed a reversal of the earlier trend back in 2000.
It cannot be anything to do with reducing Arctic ice for the following reasons:
I) Up to 2000 reducing ice was for 20 years accompanied by more poleward zonal jets. The opposite of what we have now.
ii) The southern hemisphere is also seeing similar changes in jet stream behaviour and sea ice has been increasing in the Antarctic.
I cannot understand how it can be that experienced climatologists are not aware of those facts.
The changes are due to solar variations affecting the temperature of the stratosphere as I explained here:
http://climaterealists.com/index.php?id=6645
“How The Sun Could Control Earth’s Temperature by Stephen Wilde: LLB (Hons.), Solicitor, Associate Fellow of the Royal Meteorological Society, guest post at Climate Realists ”
Monday, November 15th 2010, 8:26 AM EST
I suspect that a sudden short term dip after a period of warming could be due to the system remaining in ”fast transfer of energy throughput’ mode for a few years after the solar warming effect ceases.
Then the speed of energy throughput slows down as the circulation changes result in more cloudiness and the system recovers somewhat from the initial dip.
@Niff – Sorry, it would actually be quite the opposite: It would only kill off anything at all, IF we DID understand the cause. — If your present understanding is formed based upon what you know already / so far, NOT adding extra insight is NEVER a reason to change anything… I hope you don’t work like that at home 😉
jai Mitchell said;
‘Absolutely no one can deny that the weather is changing in the extreme. Keep your eyes on the arctic.’
I replied to this nonsense in the Muller thread. We can see numerous examples of blocking highs and jet stream movements in the old weather observations dating back hundreds of years. If you are British you need to learn more about the climatic history of your own country. Read some Lamb and then follow it up with a comprehensive overview from Ladurie..
tonyb
jai points out the higher pressure recently over Greenland and the Northern Arctic in general but fails to note that the switch to such a negative AO is pretty much coincidental with low solar activity.
In contrast, the high solar activity of the late 20th century was coincidental with a generally positive AO.
The same relationship was observed in the cooler middle part of the 20th century, the warmer early 20th century, the LIA and the MWP.
The evidence is clear in my view.
In ice ages the AO would have been even more extremely positive with climate zones and jets pushed way down towards the equator. In those cases orbital changes altered the solar effects whereas on shorter time scales (1000 years or so) the changes appear to arise from cyclical shifts in the mix of particles and wavelengths from the sun as activity waxes and wanes.
Such changes in mix appear to alter stratospheric temperature differentially between equator and poles thus affecting the gradient of tropopause height between equator and poles thus allowing the jets and climate zones to slide to and fro latitudinally.
The mechanism is via changes in the balance of destruction and creation of ozone at different heights.
Overall, an active sun cools the stratosphere whilst an inactive sun warms the stratosphere which is the opposite of established climatology but matches observations if one takes the assumed effects of CO2 and CFCs out of the mix.
I think it will turn out that the cooling stratosphere of the late 20th century was nothing to do with us after all or if we had any effect it was dwarfed by natural variability
Here is Cet from 1538 to the present day measured in 10 and 50 year periods and showing the 1740 dip well.. The overall variability can be readily seen. Note , it is my reconstruction from 1538 to 1659 which is the start date of the CET instrumental record.
http://climatereason.com/Graphs/Graph09.png
tonyb
Although statistically significant data is helpful in confirming or disconfirming CAGW theory, I think well-meaning scientists risk falling into the same trap as CAGW zealots, when presenting data with little statistical significance; which this data, with an R2 of just 0.11, appears to be.
Yes, it would be interesting–and damning–to CAGW theory if there was a sudden and severe drop in global temperatures within the next 2 years, but if the opposite should happen with a strong El Nino event, then perhaps some credibility is lost.
Perhaps I’m reading too much into this post, but I do believe discretion is the better part of valor.
I hope to heck that this doesn’t happen.
The UK’s energy supply is in such a parlous state due to the green agenda. Wind turbines don’t work well when they are frozen !!
They need time to build it back up, which they will have if the coming temperature decline is gradual. If its a quick drop, they are in deep trouble. !
If Obama gets his way, America could have real energy supply problems well. They need to stop that idiocy in its tracks before its too late !
At least Germany and China will have the benefit of a good solid coal powered electricity system. Neither a warming climate or a cooling one is a major issue so long as your energy supply system is robust. Unfortunately, this is an area where great damage has been done by the CAGW hoax.
That is not a match in any reasonable sense but an exercise in self-deception. You can “match” any two relatively short stretches of a smoothed noisy signal (smoothing makes them look like waves). Despite that, in this case, the agreement is still poor.
And what’s this about ice melt.?
The Arctic Sea Ice area, for June, is above any value its been in the last 8-10 years !
http://www.natice.noaa.gov/ims/images/ims_data.jpg
Wiggle²=0.meaningless.
And the weather here in the UK is not ‘extreme’. We are used to it – that’s why we talk about it all the time.’The coldest spring for a hundred years’ we read – what caused it a hundred years ago? I ask. The Met have always struggled to predict the weather.
SAMURAI says at June 19, 2013 at 12:09 am
Spot on.
Weather is not climate.
TonyB’s work on long term trend in the Midlands is climate.
A couple of bad (olr good – it’s subjective) years is not signiicant. It is weather.
jai mitchell says: June 18, 2013 at 9:25 pm
“Yes Dorothy, it really IS climate change…Absolutely no one can deny that the weather is changing in the extreme. Keep your eyes on the arctic.”
///////////////////////////////////////////////
Having lived in the UK for approximately 50 years, I am unaware of any climate change as far as the UK is concerned. Sure there have been variations from year to year, but nothing beyond the bounds of natural variation, and nothing which indicates some form of climate shift.
Since 2000, CET has fallen by about 0.5degC, which effectively cancels out half the warming seen in the 20th century. CET winter temperatures have fallen by about 1.5degC. As far as winters are concerned, this has cancelled out the 20th century warming.
2 points to note:
(i) the fall in winter temperatures (Dec to Feb) is substantial (-1.5degC) but since the annual fall is only 0.5degC it follows that there has been much smaller reduction in the other seasonal average anomaly, indeed, summer temps have fallen little. So this is mainly a winter phenomena.
(ii) since it is mainlly a winter phenomena, Arctic ice coverage has little to do with matters. Arctic ice reaches a summer minimum in September, thereafter it begins to recover. Winter ice extent in the Arctic has not varied much. The reality is that the ice extent in December and January, just when the UK is receiving its cold weather, is not significantly different from the long term norm!
Of course, the UK has in the past had some cold winters, eg., the winter of 1963 and the late 40s. Are you suggesting:
(a) that these were the result of Arctic ice extent?
(b) Are you suggesting that in 1963 and 1948, the Arctic ice melt was similar to say the period 2009 to 2012?
(c) If those cold winters were not due to the state of Arctic ice in those years, what caused those winters to be cold?
(d) If when answering (c) you allege that they were not due to Arctic ice extent but due to some other reason, please explain why that other reason is not responsible for the cold winters seen from 2009 onwards.
I cannot see what there is not to like about an ice free Arctic. The melt does not give rise to sea level rise (since Arctice ice is floating sea ice), and it is part of the self regulator, namely that an ice free Arctic allows heat from the Arctic ocean to radiate to space rather than being trapped by ice (which acts like a lid on a sauspan preventing heat loss from the ocean), and this increased heat loss would more than off’set any extra heat brought about by change in summer albedo.
It is funny that if the weather is changing, all or nearly all records are in the past, namely warmest day, coldest day, rainiest day, coldest winter, wettest year etc. These are all past records. This strongly suggests that weather is variable and any perceived recent change is not outside the usual limits of variability.
Two questions for consideration and request for references:
(1) Is it established that during ice ages the jet stream was at much lower latitudes and that temperate/tropic temps were above “normal” for a nearly “normal” TSI? Cue pictures of balmy conditions within close proximity to a wall of ice.
(2) Has there been recent literature discussing an Ice Age “see-saw” with NH ice cover 12kyr ago and SH (i.e., Atarctic) Ice Age now? Ice reached around 40N where most land in SH is closer to equator than 40S.
Cheers.
Bill
I represent Joe Public who knows nothing about climate science but read this site with a huge amount of interest. What brought me here? Alarmist media claims that made me afraid for my family and so I wanted to know more – to be informed. The alarmist media have created a psyche in the general population that almost ANY weather event of interest is AGW related. It is only when you point out to people that we had snow in 1964 and 100 years ago that was similar to what we have experienced recently that they then break the link between weather events and supposed AGW. And even in the face of falling temperatures articles like this http://www.bbc.co.uk/news/science-environment-22913559 appear that STILL bang on about how a rise in 2 degrees cannot be avoided and that this means we are all going to starve.
Anyway – sorry to interrupt the intellectuals! Post on 🙂
DMarshall says:
June 18, 2013 at 10:16 pm
….Does that have anything to do with the extremely warm temps in Alaska right now or is that a separate phenomenon. I’ve heard reports of temps ranging from 82 – 98 degrees across the state after having unusually cold temps until just recently.
>>>>>>>>>>>>>>>>>>
Actually yes. This is what Stephen Wilde has been going on about for years. comment link
Blocking Highs are to be seen frequently when the Jets move from Zonal flow to Meridional flow as they have done in recent years. (For definitions and descriptions see link 1 and link 2) The Russian drought a few years ago was caused by a Blocking High. NASA: Extreme 2010 Russian Fires and Pakistan Floods Linked Meteorologically… research finds that the same large-scale meteorological event — an abnormal Rossby wave — sparked extreme heat and persistent wildfires in Russia as well as unusual downstream wind patterns that shifted rainfall in the Indian monsoon region and fueled heavy flooding in Pakistan.
This is why the CAGW Media propaganda has switched from ‘Global Warming’ to ‘Weather Weirding/Extremes’ Meridional flow IS going to give you weather extremes, such as droughts, floods, extreme heat and extreme cold. This means you can get great headlines. Remember
The whole aim of practical politics is to keep the populace alarmed (and hence clamorous to be led to safety) by menacing it with an endless series of hobgoblins, all of them imaginary. ~ H. L. Mencken
And the goal of politics is control of the population while they and their buddies extract as much wealth from the sheeple as possible. Why the general population has not figured that out and realized ALL our present politicians with few exceptions no matter the affiliation are crooks is beyond me.
jai mitchell says:
“The state is now so extreme that the Met is calling a meeting of the world’s climate experts to discuss what the future may hold.”
What is extreme is the corner they’ve got themselves into.
They are looking for an exit strategy. They were the first and AFAIK still the only major national climate research body to down-grade their short term climate predictions. I think they have understood what is about to happen and are trying to work out how to U-turn after 30 year of alarmist without looking totally stupid and incompetent.
At least they are looking for a way out. Others are still looking for the ‘missing heat’.
OOPS
The NASA link on the Russian drought is this link.
@ mark. “’The coldest spring for a hundred years’ we read – what caused it a hundred years ago”
And down here (near Sydney, Australia) this year we finally reached the temperature record of 74 years ago, after all this warming . and of course Sydney hasn’t grown as an urban centre at all since then 😉 No urban warming down here, y’know !!
Niff says:
June 18, 2013 at 9:00 pm
Well even if we don’t understand the causes, and even if we have to suffer a debilitating cold spell..it would at least kill off the CAGW nonsense….you would think?
===========================================================
Probably not. CAGW is a religion, not science.
AB says: @ June 18, 2013 at 11:18 pm
Air temps in the Arctic are lower than normal for this time of the year…. Interested to hear what others may think about this.
>>>>>>>>>>>>>>>>>>>>>>>
If the temp continues low and more importantly the North Atlantic is cooler so the Arctic ice ‘Recovers’ we can expect a media blackout on those facts and lots of spin by the Peccatogenesists.
Stephen Wilde says: jai points out the higher pressure recently over Greenland and the Northern Arctic in general but fails to note that the switch to such a negative AO is pretty much coincidental with low solar activity.
I’m still trying to understand why CO2 at Mauna Loa seems so closely linked to AO.
http://climategrog.wordpress.com/?attachment_id=259
Especially since 2000 AO seems to account for almost all the variation from the mean rise of 2ppm/a
The two phase shifts I fitted seem close to the two of main peaks in E-W trade wind speeds:
http://climategrog.wordpress.com/?attachment_id=281
I have not looked at the timing of those cycles post- and pre-2000 but that may be interesting.
When I say still trying to work out , a lot has to be to do with Henry’s Law as I noted under the graph. I just don’t see why Arctic is either so dominant or else correlated to that which does dominate.
Henry’s Law:
the solubility of a gas in a liquid is directly proportional to the partial pressure of the gas above the liquid.
@David – The graphs don’t have anything that I see as predictive. What was left out? The solar cycle overlay?
@Jai – you have got to be kidding me. This is about the most ridiculous claim ever.
” A permanent blocking high pressure system has formed over Greenland.”
Permanent? Did I miss some Icelandic volcanic active that put up a 15 mile high dike recently?
BC – Before Coffee – “… Icelandic volcanic activity that…”
I’ve been having an intuition for the past year or two that a sharp global temperature drop is coming. This is basically because I think the Pranksters on Olympus are in charge of world events; that their main motive is to provide endless demonstrations of “what fools these mortals be” by whacking hubristic know-it-alls with cosmic custard pies; and that climatologers have painted big bullseyes on themselves.
I like the intuition, because it would put a big arrow in the alarmist elephant and bring it to its kness, never to rampage again, even if temperatures were eventually to recover most of the way from the dip (as they did after 1740). A big dip would show that the percentage of variation that occurs naturally is much higher than the models assume. It would dramatically violate the 95% certainty band of the IPCC’s forecasts for upcoming years in a dramatic way—and, by extension, turn the implication of the 97%-consensus claim from a validation of cli-fi (“they can’t all be wrong”) to an indictment of it (“they’re all full of it—the whole field is pseudoscience”). And it would also greatly unsettle “the science” and the supposed certainty the alarmists have that there are no unknown unknowns. Once the alarmist narrative has been thrown off-stride and flustered, it will lose its political and social momentum. (If they play the ocean acidification card, the world’s reaction will be, “fool me once . . .”)
This chart of the CET’s 1740 dip-event shows the sort of dip that would match my outlandish intuition. I think that, even if the mathematical correlation is poor, the “set up” (to use a stock traders’ term about how “the stars are lining up”) looks good, by eyeball. Here’s how I figure it:
The eighteenth century line shows nine peaks before the crash in 1740. There are seven peaks in the modern-period line up to the present. There is only one outright clash in the lines: in 1712-13, when there was a peak, but where the modern period’s line dips. There is a less-than perfect match-up for the years 1728-38, where there are three peaks and two dips (in a warming trend), vs. the modern period’s long warm plateau. Another imperfect match is the modern period’s more severe dip in “1738.” Other than that, my eyeball is impressed with the startling general correlation of the rips and dips.
So I suspect the Pranksters are giving us a heads-up that 2014 & 2015 will be very chilly. (If Intrade were still in business, I could get long odds if I bet that way. UK residents can probably get such odds via bookmakers like William Hill.)
Some anecdotal evidence that agrees with the idea that 1740 was unusually cold in the British Isles is that in 1742, a Dublin landlord, John Mapas, commissioned the construction of a large obelisk at the top of Killiney Hill – an expensive suburb of Dublin in Ireland, with spectacular views of Dublin Bay. The motivation he gave was to provide employment for many of the poor people who had been badly affected by the famine brought about by the unusually harsh winter of 1740/1741. This is the pre-potato famine that David Archibald refers to in this post. Ireland also suffered unusually harsh winters in 2009/2010 and 2010/2011…
If any of you have ever visited Dublin, you will probably have seen the obelisk. It’s visible from most places along the coast-line that are south of the city.
Two years to a 1740-type event?
Not quite, it’s 3.5yrs to a 1838 event, aka Murphy’s Winter, with a very long and cold spring in 2016 coming too. The best analogue of 1740 is 1919, with the cold shots starting January and May 1740, having heliocentric analogues 179yrs and ~1 month later, from February and June 1919: http://climexp.knmi.nl/data/tcet.dat
In five years of forecasting for temperature deviations from average in the UK, I don’t see much lag between a particular heliocentric configuration, changes in solar metrics, changes in Arctic pressure and hence jet stream position, and the resulting change in temperature and weather type for the UK. A week at the most unless there’s a very persistent block.
rogerknights says:
June 19, 2013 at 3:43 am
Another way of looking at the 1740 dip is that the chaotic climate system was dropping toward the ice age attractor but for some reason did not escape the ‘Holocene interglacial attractor’. If we have another such event perhaps with a slightly different set of variables, the climate system may escape the Holocene interglacial attractor and be captured by the ice age attractor,
@Stephen Wilde and @J’ai
The effect of a zonal/meridonal jetstream over the UK was seen last year with continual rains and poor weather and harvest problems. Although the rain has not been as continual the UK is still having poor weather and harvest problems. This we can attribute to a blocking / omega high around Greenland. Now in history we cannot go back to look for anticyclones over Greenland what we can do is look for reports of extended poor weather and harvest problems that shows the existence of a blocking high and stationary Rossby waves in the jetstream. The poor weather and continual rain is normal when the climate changes from warm to cold. It happened just the same way at the end of the Medieval Warm Period as the climate moved into the Little Ice Age. From the book “The Long Summer: How Climate Changed Civilization” By Brian M. Fagan –
“Seven weeks after Easter in A.D. 1315, sheets of rain spread across a sodden Europe, turning freshly plowed fields into lakes and quagmires. The deluge continued through June and July, and then August and September. Hay lay flat in the fields; wheat and barley rotted unharvested. The anonymous author of the Chronicle of Malmesbury wondered if divine vengeance had come upon the land: “Therefore is the anger of the Lord kindled against his people, and he hath stretched out his hand against them, and hath smitten them.” Most close-knit farming communities endured the shortages of 1315 and hoped for a better harvest the following year. But heavy spring rains in 1316 prevented proper sowing. Intense gales battered the English Channel and North Sea; flocks and herds withered, crops failed, prices rose, and people again contemplated the wrath of God. By the time the barrage of rains subsided in 1321, over a million-and-a-half people, villagers and city folk alike, had perished from hunger and famine-related epidemics. Giles de Muisit, abbot of Saint-Martin de Tournai in modern-day Belgium, wrote, “Men and women from among the powerful, the middling, and the lowly, old and young, rich and poor, perished daily in such numbers that the air was fetid with the stench.” People everywhere despaired. Guilds and religious orders moved through the streets, the people naked, carrying the bodies of saints and other sacred relics. After generations of good, they believed that divine retribution had come to punish a Europe divided by war and petty strife.”
This was ‘The Great Famine’ of the 1300’s
Of course then the majority of people were Christian so they believed that they had angered God, Nowadays the majority religion is Warmist, so the belief is that we have angered Gaia by our CO2 emissions.
No doubt an extended cold snap would somehow be blamed on CO2 and CAGW.
It would be no less credible than the current fear-mongery.
The Daily Telegraph report on the UK Met Office meeting yesterday included this gem attributed to the happily named Prof. Belcher:-
“We do not know how much is down to natural cycles and how much is down to climate change.”
The inference, for the great unwashed, is that climate change is not natural.
Jai,
Blocking highs occur all the time…everywhere. They form almost unpredictably (at least can’t be predicted more than a couple weeks in advance) and they eventually disappear and/or move almost unpredictably. You can watch any global pressure weather map and see them all over the globe. They last from weeks to a couple of years and vary in ‘intensity’ over a wide range.
When they stick around for several months, they might make the news as colder than normal weather in one location or warmer than normal weather at another. Recently, some persistent ones have caused the current cold weather in northern Europe and some heat waves in central Europe and Siberia. When they happen over the 75% of the planet occupied by water they don’t show up in the weather news…despite how severe or persistent they may be.
Jai, blocking highs are normal and have always occurred. The ‘news’ is recently making them appear as climate related disasters which they not. They are merely perturbations in the random weather patterns that have always taken place. I know of no studies that have made them worse over the last 100 years versus the previous 10,000 years.
So go long Wheat and gas stocks?
GlynnMhor says:
June 19, 2013 at 5:09 am
No doubt an extended cold snap would somehow be blamed on CO2 and CAGW.
It would be no less credible than the current fear-mongery.
It already has! 😀
The year 1740 may have been a global or Northern Hemisphere wide cold event.
CLIMATE4YOU web page has these bits of news about a very severe winter in the US MASSACHUSETTS back in 1740/1741[ and again 1747/1748. (Perley 2001).]
Not only was the winter 1740-1741 characterised by very low temperatures, but also by huge amounts of snow. People in the region saw this winter as the most severe since the European settlement began. There was 23 snow storms in all, most of them being strong. On 3 February about a foot of snow fell, and about one week later there were two more storms, filling the roads in Newbury, Massachusetts, up to the top of fences. Snow depths of about 3 metres were reported from some places.
If the temp. drops in 2015, you can be sure that global warming will cause it and not the sun. 😉
herkimer says:
June 19, 2013 at 6:15 am
The winter of 1740 rates its one entry in the climate history of New England:
http://www.colonialsense.com/Society-Lifestyle/Signs_of_the_Times/New_England_Weather/1740-1_Winter.php
Silly denialists… it was the faulty smog controls on the 1739 SUVs….
Greg Goodman (June 19, 2013 at 3:08 am) wrote:
“I’m still trying to understand why CO2 at Mauna Loa seems so closely linked to AO.”
Interannual variations of all indices are coupled globally.
David
It looks to me that this 1740 cold spike year was perhaps the typical temperature drop that happens around and after an El Nino event. If the El Nino event was a major one , which the reconstructed PDO records actually show for about that time , then the temperture drop can also be significant . El Nino events also set up negative AO conditions which allow extra amount of cold Arctic air to come further south.It looks like this could also be the trough of a 60 year climate cycle . If you measure back 60 year intervals from1970 , you end up at about 1740. We are heading into the trough of a 60 year climate cycle currently , the bottom of which may be a decade or two away yet.
Figures 8 & 10 here:
http://www.atmosp.physics.utoronto.ca/SPARC/SPARC2000_new/PosterSess3/Session3_3/Georgieva/doklad.htm
“Ronan says:
June 19, 2013 at 4:03 am”
I lived in southern Ireland, Waterford, in very very “wet” weather conditions between 1977 – 1981. Not sure how that relates to the potato blight, but “damp weather”, was a factor in history teachings back then if I recall correctly.
Is there a download link to the London wind data?
Year 2000 was the Peak of Solar output for a while. The surface of the core of the Sun will now need to “recharge” its Hydrogen before the Sun’s output will increase. The center of the core of the Sun in not where fusion takes place; it is where the waste products from Hydrogen burning fall. Note that every Sun sequence ends with Iron in the core: not Hydrogen. We are a long way from an Iron Core, but we are in a natural 350 to 400 year cycle of Hydrogen burning then replenishment. This cycle appear to behave like a “sawtooth”. A gradual rise to the peak, then a sudden drop: repeat.
Watch the Gulf of Mexico to see the averaged effects of the reduced Solar output. As the Gulf of Mexico cools, the Gulf Stream will cool and slow, therefore, England and Europe will not get Atlantic Ocean heat. The result will be a frozen England and Europe.
England is located ~at 55N Lat. This is where Hudson Bay, Canada, is located in North America. Trust me, there are only two temperatures there: cold and colder, winter and deep winter.
David
You could be right that we will have a colder winter by 2015. Here is how I see it however.
The minimums of the longer solar cycles are deeper and more severe or colder than the short ones. There are 50- 60 and 110-120 years and even longer climate cycles that emerge from sun/ocean interface. The 50- 60 year climate cycle which seems to be oceans driven and consist of alternating 30 years cooler weather and 30 years of warmer weather. We just came out of the 30 year warm cycle and are now heading into 30 years of colder weather. The 110-120 climate cycles which seem to correlate with periods of low solar sunspot activity last troughed around 1890, 1780, 1670 and 1560.These periods can be clearly seen in the CET graphs of Tony Brown and the WUWT web page Significant cooling followed these dates in the past. We are now entering the start of the trough period of this longer 110-120 year climate cycle which tends to be colder than the typical 30 year cool cycle trough. The current decade is also about 200 years since the Dalton Minimum or the end of the 200 year solar cycle which again tends to be deeper and colder than the 60 year or 100-120 year minimums , Thus the winters MAY be getting progressively colder for the next several decades. The 2013/2014 winter MAY be colder than the last winter and the subsequent winter 2014/2015 may be colder still. The winters MAY stay cold for the next several decades.
gymnosperm says: June 18, 2013 at 11:08 pm “Jai, To the best of my understanding melting ice would release enthalpy of fusion, warming the ocean”
When I put an ice cube into my glass of water, I expect it to cool the water.
I don’t think it looks like a dragon at all. It looks more like a bunny rabbit.
Patrick says:
June 19, 2013 at 7:22 am
I lived in southern Ireland, Waterford, in very very “wet” weather conditions between 1977 – 1981. Not sure how that relates to the potato blight, but “damp weather”, was a factor in history teachings back then if I recall correctly.
In general, Ireland is wet, so I’m not surprised! We’re right on the edge of the Atlantic Ocean, and so get a lot of rain.
But, you’re right about the (more infamous) 1840s potato famines being mainly due to particularly “damp weather” causing potato blight. Potato blight doesn’t seem to have reached Europe until the 19th century, however. Instead, the 1740-41 famine seems to have been mostly cold-related, rather than rain-related: http://en.wikipedia.org/wiki/Irish_Famine_(1740-41)
Indeed, one of the pleasant aspects of the 2009/10 and 2010/11 cold winters was that it was actually much drier – just a lot colder than we’re used to. Plus, we don’t usually get much snow, so it was quite pretty.
My link above didn’t seem to work right for some reason. Here it is again: http://en.wikipedia.org/wiki/Irish_Famine_(1740%E2%80%9341)
This is a fairly unbelievable reach to be posted on the #1 science blog.
@ Greg Goodman, you said “or else correlated to that which does dominate.”
You might want to check out some of Vuk’s graphs where he gets remarkably good correlation between polar magnetic fields and temperatures.
jai mitchell says:
June 18, 2013 at 9:30 pm
More research on the Greenland blocking high
http://www.washingtonpost.com/blogs/capital-weather-gang/wp/2013/03/21/record-blocking-patterns-fueling-extreme-washington-d-c-march-weather/
As stated, a blocking pattern like this ranks among the strongest ever; to further illustrate that fact, I have plotted the 500 mb height composite anomaly from the 12 separate dates on which the AO plunged to its most negative values in recorded history. The composite, shown below, reveals positive anomalies in excess of 350m near Greenland – neatly matching the current block’s intensity.
One more remarkable aspect of this major league block: observations over Greenland are threatening to break the worldwide record for highest barometric pressure of 1083.3 mb, set on Dec. 31, 1968 in Siberia. NCEP’s Ocean Prediction Center analyzed the surface map (from Tuesday night) below, which features a high pressure center of at least 1074 mb over Greenland.
You don’t get research from newspapers.
These are somewhat imaginary pressures because in the case of Greenland the actual highest measured pressure at Summit Camp (3209 meters altitude) was 691.1mb at midnight 21 March 2013 when the temperature was -47.8C; referred to sea level using the ICAO Standard Atmosphere correction this is 1073mb. Twelve hours later, the measured pressure had only fallen 0.6mb but the temperature had risen to -32.7C which when corrected gives 1052mb – a huge difference.
The 1968 Mongolian record (1083.3mb) was set at an altitude of 261 meters so the pressure when referred to sea level using the ICAO Standard Atmosphere correction is less affected by temperature which was between -40C and -50C on the day of the record. At -50C the measured pressure at Agata (the record site) would have had to be 1035.6mb and at -40C the measured pressure would have had to be 1038.9mb to achieve the record value when referred to sea level.
Oh, by the way, the WMO Extreme Weather Records Committee don’t accept pressure records from sites above 750 meters elevation. That pretty much rules out most of the Greenland ice cap so ‘major league’ blocks over Greenland won’t be threatening any records.
Wiggle-matching: we’re looking for correlations that can be used for predictive purposes, so they are useful. There is much complaint that we use correlation to determine causation – like the correlation between the numbers of pirates and temperatures. Fact is, in a practical sense, we shouldn’t care if we don’t understand the connection to some other, common cause. If we note that hog prices in Chicago rise two weeks before silver prices 75% of the time, we can use that correlation to become rich. When something works we shouldn’t turn our noses up at it because we don’t understand why it works.
We are in a time where our historic temperatures are maybe 1C higher than they were pre 1740, and warmer than we were pre-1820. If temps fall, they will start higher, but whether they fall a certain amount or to a certain level is disputable. I would say a certain amount, believing that in the shorter term we suffer variation from a present mean, not a long-term or future term mean. If so, we could go back to the early 60s, or perhaps the 20s. Not the 1820s or the 1740s, though.
The other thing to remember is that a drop of 1C in the Central UK correlates with a drop of perhaps 0.4C globally – look at all the temp profiles of global, hemispheric, land-only, SST-only, individual countries, individual regions within countries and individual sea/ocean basins. CEUK is not the world, though those of a London-lifestyle (like New Yorkers) often act as if it is.
The future, I agree is colder, but not a disaster. Except to the warmists, (who would delight in a 1C spike for 10 years, thousands of deaths from heat stroke and dehydration in war-torn Africa, and mass migration to Dairy Queen ice cream shops. How peculiar it is when you wish to be right).
Looks like 1740 was another case of a recent switch to a negative PDO while the AMO is strongly positive. The resulting atmospheric pressure zones create high pressure over the N. Atlantic sending the jet stream northerly and then it sweeps down over western Europe. Not a global effect.
The main reason for bitter winters here in the UK are the jet stream pushed to the south and blocking highs. lf the very low temps came with mostly with sharp frosts and winds that were mostly from the north then it was a Greenland block. lf the winds came in from the east then a blocking high was sitting to the north of the UK. But if they were low temps that came with very heavy snow then the most likely thing that was happening was that the jet stream split (most likely over the ocean) and a branch of it pushed up to the north flowed over the pole and came back down on the other side of the Earth. lts this sort of jet stream pattern that causes very sudden cooling, with bitter winter weather and heavy snow.
Dr. Lurtz says:
June 19, 2013 at 7:29 am
Year 2000 was the Peak of Solar output for a while…. we are in a natural 350 to 400 year cycle of Hydrogen burning then replenishment. This cycle appear to behave like a “sawtooth”. A gradual rise to the peak, then a sudden drop: repeat….
>>>>>>>>>>>>>>>>>>>>>>>
So how come Svalgaard and company say the sun’s output is ~constant and are ‘adjusting’ the historic sunspot record?
Although I did like your explanation here.
In the rest of the comment you go into further detail of a ‘reasonable model of the internal workings of the Sun’ and Svalgaard weighs in further down in the comments.
I wonder if there is any causal relationship between the temperature phenomena in 1745 and the Scottish uprising of 1745?
With the way the jet stream is looking at the moment, the coming winter looks to be setting up a hard winter for many in the NH.
With central northern asia, europe and Canada looking the most at risk.
In looking deeper on this ,the 1740 record winter cold was part of a much longer climate event that culminated in the very cold January [-2.8 C] and February [-1.6 C] and overall winter of -0.4 for 1740. The annual climate had been cooling since about 1733 and all seasons were cooling except the winters which really only started to cool significantly about November 1739 and nose dived in 1740. There were below normal temperatures from about November 1739 to almost june 1740. Winters stayed below normal for almost 6 years there after. I very much doubt if this was some short term blocking incident of the jet stream but anyting is possible I suppose. Could also be SSW caused ?
Retired Engineer John says:
June 19, 2013 at 7:44 am
“When I put an ice cube into my glass of water, I expect it to cool the water.”
Not if you had more ice to start off with, which had been melting because of increasing ambient temperature. The water temp would gradually warm.
That dip kicked off a few decades with lots of fun and games especially within the UK and its possessions at the time (he wrote a mere few days prior to 4-July).
Bob Rogers says:
June 19, 2013 at 11:45 am
I wonder if there is any causal relationship between the temperature phenomena in 1745 and the Scottish uprising of 1745?
—————————————
Probably not much. The timing of the ’45 was determined by the War of the Austrian Succession more than climate. Bonnie Prince Charlie was a tool of French war aims. With the British Army occupied in fighting on the continent, France planned invasions of both England & Scotland to restore the Stuart dynasty, backed by many Tories, out of power under the Whig-dominated Hanoverian Georges. In the event, only the Scottish plan went ahead, but without the originally proposed French support.
Historians disagree over the causes of the Industrial Revolution of the mid-18th century, but the cold LIA climate may have contributed to the innovations of that period. Its onset is generally dated around 1760, but some key technological improvements occurred before then.
herkimer says:
“The annual climate had been cooling since about 1733..”
It looks warm to 1738 to me: http://climexp.knmi.nl/data/tcet.dat
There was a solar cycle maximum in 1739, it is common to see hard winters close to maxima.
All,
there are simply too many to respond to all at once, I understand why some here would be skeptical about the blocking patterns in the atmosphere. This simply presentation shows why the blocking patterns are happening. These patterns did happen on a regular basis but they did not happen after the fall, they NEVER happened in the summer and the jet stream is so erratic now we are getting cut off lows and blocking pattern highs that are throwing the Jetstream in an East to West pattern as is shown in the following video. You don’t need me to tell you how the meridional flow of the jet stream moving to the extreme and causing an east to west flow is EXTREMELY unusual.
This is the presentation by Jennifer Francis who very simply describes why this is happening.
URIC LYONS
I looked at the CET ANNUAL TEMPERATURES which peaked at 10.47 C in 1733.You can check it on the Met Office data base HadCET mean.
From jai mitchell on June 19, 2013 at 3:51 pm:
From her Peer-reviewed Publications list at her Rutgers faculty page, see seems very proud of her last paper, Francis, J. A. and S. J. Vavrus, 2012: Evidence Linking Arctic Amplification to Extreme Weather in Mid-Latitudes, Geophys. Res. Lett., Vol. 39, L06801, doi:10.1029/2012GL051000 PDF
She’s quite a science celebrity, with about 49 appearances and mentions proudly listed. Sample:
Skeptical Science 4/11/12
http://www.skepticalscience.com/Linking_Weird_Weather_to_Rapid_Warming_of_the_Arctic.html
NewScientist article 7/9/12
http://www.newscientist.com/article/mg21528721.800-how-global-warming-is-driving-our-weather-wild.html?page=1
Climate Central post 22 August 2012
http://thinkprogress.org/climate/2012/08/22/727501/arctic-death-spiral-how-it-favors-extreme-prolonged-weather-events-such-as-drought-flooding-cold-spells-and-heat-waves/?mobile=nc
I really love this one:
Citizen’s Climate Lobby 10/26/12
http://citizensclimatelobby.org/content/q-role-global-warming-plays-extreme-weather-such-hurricane-sandy
SST’s at all-time record high off Northeast North America? Where’s Tisdale?
Bob Rogers says:
June 19, 2013 at 11:45 am
I wonder if there is any causal relationship between the temperature phenomena in 1745 and the Scottish uprising of 1745?
>>>>>>>>>>>>>>>>>
Generally there is. Hunger is a great motivator even today. In 2008 more than 60 food riots occurred worldwide in 30 different countries. Unfortunately we are not very far from a repeat of the 2008 food riots since the USA, a major grain producer no longer has a Strategic Grain Reserve but is instead importing grain. link
From the UN (FAO) food price index graph NOTE: the real price is the nominal price Deflated by the World Bank. Deflated??? What the heck happen to inflation?
jai mitchell says….
Do you have anything written. I do not have sound on my computer.
RE: Jai Mitchel
Among the many ideas that try to explain why we move through periods where the jet stream are zonal and periods where blocking patterns make the jet stream loop and even produce cut-off-lows, (in a way like an oxbow lake next to a river,) the one that has you so excited is interesting.
A different theory which also might enthuse your eager mind involves the AMO and PDO. While the entirety of both oceans don’t change greatly, when averaged out, the locations of warm and cold pools do shift. When the AMO is in its warm phase, the entirety of the ocean is pretty normal, but the warmth is up where it can melt polar ice and get noticed.
When the PDO and AMO are both in “warm phases” together, or are both in “cold phases” together, there is harmony, and the jet streams are zonal. They make a nice ring around the pole. However when one is in a warm phase as the other is in a cold phase, harmony gives way to discord, the jet stream gets all out of whack, and it loops all over the place.
While I understand this theory is different from the theory you currently are focused on, I think it does a fairly decent job explaining current changes.
I also suggest you take care when dealing with terms such as “highest since records began.” The problem is that many records begin not even sixty years ago, and both the AMO and PDO swing through their cycles in a period which is (very roughly) sixty years in duration.
Lastly, be aware the cycle of the PDO and AMO are but one factor in a chaotic system. As such they are not written in stone, but rather rather are written on water and air, and they can be moved by other factors, such as the sunspot cycle. The fact the current sunspot cycle may involve a “minimum,” may actually incorporate yet another cycle, of a much longer duration.
My own guess? We are headed for a very cold winter, and it will not take two years to get here, in my neck of the woods, in New Hampshire. I’m starting to collect my firewood early.
kadaka (KD Knoebel) says: @ June 19, 2013 at 5:23 pm
SST’s at all-time record high off Northeast North America? Where’s Tisdale?
>>>>>>>>>>>>>>>>>>>>>>>>>>>
Actually the SST’s have been cold and so has the weather in mid NC. It is now 69F and we have only had two days above 90F so far this year compared to thirty one days over 90F ten years ago.
François GM says: June 19, 2013 at 2:06 pm
Retired Engineer John says:June 19, 2013 at 7:44 am
“When I put an ice cube into my glass of water, I expect it to cool the water.”
“Not if you had more ice to start off with, which had been melting because of increasing ambient temperature. The water temp would gradually warm.”
It requires 3.33x10E5 Joules to melt one kilogram of ice. This energy is taken from the water and cools the water. The ambient air temperature will not heat the water above 0 C as long as ice is present.
===========================================================
Jai, I’m not making a comment on what you have said. But the “style” in which you make your comments makes it difficult sometimes to tell whether you are quoting something followed by your response or making a number of separate points.
If the later, perhaps add to your style “1.”, “2.” etc. for the new points?
jai mitchell says:
June 19, 2013 at 3:51 pm
Take a deep breath; I have it on good authority that all this will pass as ‘there is nothing new under the sun’.
.
Caleb says: June 19, 2013 at 6:40 pm
….
Caleb, EM Smith (and Ian Wilson) had some interesting observations about the effects of the moon. we are all aware of the tides but that is not the only effect. (both link to peer-reviewed papers)
The take home is the moon’s orbit is not simple. It moves not only around the earth but up and down in relation to the earth’s equator. This could have an effect on the oceans and could be the cause of Bond and D/O events.
Another post from EM on lunar cycles
Ian Wilson has taken the idea even further.
jai mitchell says:
Jai, to be honest, I’m a bit confused as to what exactly you’re trying to say.
To me it seems David Archibald’s post is merely putting forward the hypothesis that the 1740/41 cold winter event in Europe (and U.S. too, according to herkimer!) was similar to the recent 2009/2010 and 2010/2011 winters. He was quite open about the fact that it was just speculation. But, it’s actually something I’ve been thinking myself for a couple of years now…
So, what exactly are you saying?
Are you saying that you believe the recent cold winters are due to high levels of Arctic sea ice melt causing changes in the jet-stream, and that you think this will pattern will become more common in the future?
If so, what is your explanation for the 1740/41 event?
Are you suggesting that the Arctic sea ice extent was similar in 1740/41 to now?
P.S. I see richard verney already asked you something similar at June 19, 2013 at 1:55 am
RE: Gail Combs.
Thanks for pointing those cycles out. I haven’t thought much about the moon’s tidal effect much, though I have come across it from time to time while skimming comments.
It is interesting to think of water slowly sloshing back and forth between the Atlantic and Pacific, over a period so long we wouldn’t notice it in a single lifetime, but might notice a side effect, such as a shift in the Gulf Stream or a cold winter.
Into my mind’s eye comes the memory of tidal pools a bit up a beach, away from the regular march of the surf. Although the waves thud at a regular interval, the tidal pool is not reached by every wave, and fills and drains with a period all its own. It seemed fairly chaotic to me, and I was glad it was not my job to predict when water would be entering the pool and when water would be exiting. (Instead my job was to relax, dabble, and work on my sunburn.) (Which sounds good to me right now.)
The video link that “jai mitchel” linked to had an odd explanation for the northward component of Hadley Cells. Rather than the simple idea that cooled air to the north sinks, creating low pressure aloft which sucks the air that has risen (due to heating) up from the south, the educator in the video suggested that, because the troposphere was higher to the south, gravity caused the air to flow “downhill” to the north.
Hmmmm.
An abrupt cooling event for one or two years due to changes in the jet stream might be a distraction. There is very strong data and analysis that shows the planet will cool due to the current solar magnetic cycle change. A strong argument can be made for cooling to Little Ice Age levels over roughly 3 to 5 years. Based on what has happened before the cooling will last 100 to 150 years. There is now the first observational evidence of cooling in both the Arctic and Antarctic. Why is there no discussion of imminent significant planetary cooling in the mainstream media?
The solar magnetic cycle is slowing down.Solar cycle 24 will be the weakest cycle in roughly 150 years. It appears solar magnetic cycle 25 will be either a Maunder like minimum or a Dalton minimum. Most likely is a Maunder like minimum based on observations.
Based on past solar observations the Maunder like minimum in solar magnetic cycle activity will last 30 to 100 years and will be followed by weak solar magnetic cycles. Based on what has happened before there will be significant cooling that will last for 100 to 150 years.
There are cycles of warming and cooling in the paleo record that correlate with solar magnetic cycle change. The planet cools when there is a Maunder or Dalton like solar magnetic cycle minimum. Greenland ice temperature, last 11,000 years determined from ice core analysis, Richard Alley’s paper.
http://www.climate4you.com/images/GISP2%20TemperatureSince10700%20BP%20with%20CO2%20from%20EPICA%20DomeC.gif
Comparison solar cycle 22, 23, 24
http://www.solen.info/solar/images/comparison_similar_cycles.png
Comparison solar cycle 24 to the weakest solar magnetic cycles in the last 150 years.
http://www.solen.info/solar/images/comparison_similar_cycles.png
There is now the start of cooling in the high Arctic.
http://ocean.dmi.dk/arctic/meant80n.uk.php
There is now record Antarctic sea ice for all months.
Antarctic Sea Ice, 2013 compared to 2012
http://nsidc.org/data/seaice_index/images/daily_images/S_timeseries.png
http://arxiv.org/abs/1112.3256
Solar activity and Svalbard temperatures
The long temperature series at Svalbard (Longyearbyen) show large variations, and a positive trend since its start in 1912. During this period solar activity has increased, as indicated by shorter solar cycles.
The temperature at Svalbard is negatively correlated with the length of the solar cycle. The strongest negative correlation is found with lags 10 to 12 years. …. …. We predict an annual mean temperature decrease for Svalbard of 3.5 ±2C from solar cycle 23 to solar cycle 24 (2009 to 2020) and a decrease in the winter temperature of ≈6 C.
William: Latitude and longitude of Svalbard (Longyearbyen)
78.2167° N, 15.6333° E Svalbard Longyearbyen, Coordinates
A Pervasive Millennial-Scale Cycle in North Atlantic Holocene and Glacial Climates
http://www.essc.psu.edu/essc_web/seminars/spring2006/Mar1/Bond%20et%20al%202001.pdf
http://cio.eldoc.ub.rug.nl/FILES/root/1999/QuatSciRevvGeel/1999QuatSciRevvGeel.pdf
“The role of solar forcing upon climate change”
However, if we observe sudden, major 14C increases like the ones starting at c. 850 cal. BC and at c. 1600 AD (about 20 per mil), it is hard to imagine any change in the global carbon cycle that can bring about such a drastic fast change, simply because there is no reservoir of carbon with higher 14C concentration available anywhere on Earth. … …We consider this scenario unlikely, and note here that events such as the 850 cal. BC peak are present in the dendrochronological curve with a periodicity of about 2400 years (Stuiver and Braziunas, 1989; see below). … …”A number of those Holocene climate cooling phases… most likely of a global nature (eg Magney, 1993; van Geel et al, 1996; Alley et al 1997; Stager & Mayewski, 1997) … the cooling phases seem to be part of a millennial-scale climatic cycle operating independent of the glacial-interglacial cycles (which are) forced (perhaps paced) by orbit variations.” … …”… we show here evidence that the variation in solar activity is a cause for the millennial scale climate change.”
https://ams.confex.com/ams/pdfpapers/74103.pdf
The Sun-Climate Connection by John A. Eddy, National Solar Observatory
A more obvious and climatically more significant feature of the long record is the recurrence of repeated Maunder Minimum-like depressions in the overall level of solar activity, each persisting for thirty to about 100 years.
Solar Influence on North Atlantic Climate during the Holocene
A more recent oceanographic study, based on reconstructions of the North Atlantic climate during the Holocene epoch, has found what may be the most compelling link between climate and the changing Sun: in this case an apparent regional climatic response to a series of prolonged episodes of suppressed solar activity, like the Maunder Minimum, each lasting from 50 to 150 years8.
I think Dr. Archibald got the second graph wrong. I suggest a somewhat different comparison as shown here
http://www.vukcevic.talktalk.net/CET1690-1960.htm
from which can be concluded that the ‘1740-type event’ if there is such a thing, is not 2 years in front but 2 years behind us.
= On the polar jet stream and stratospheric warming =
– Under normal conditions PJS is a regular Rossby wave, due to shear in rotating fluids, so that the Coriolis force changes along the sheared coordinate. In planetary atmospheres, wave is due to the variation in the Coriolis effect with latitude.
http://uvs-model.com/pictures/jet_stream.jpg
– The lobes of the PJS become more meridionaly pronounced by change in the events associated with strong ocean – atmospheric interaction, i.e. two semi-permanent low pressure systems:
a) Icelandic Low in the N. Atlantic caused by warm currents down-welling
b) Aleutian Low in the N. Pacific caused by cold currents up-welling.
both of the above have coincidental correlation with the pronounced tectonics in both areas.
– Sudden stratospheric warming, only happens in the winter months and its occurrence is strongly correlated this time to the frequent volcanic eruptions in Kamchatka peninsula; more details here:
http://www.vukcevic.talktalk.net/NH.htm
The warm air dome rising from eruptions ruptures tropopause (the boundary in the Earth’s atmosphere between the troposphere and the stratosphere) and so allowing large volumes of the troposphere’s air to rise into stratosphere, as clearly demonstrated by this NOAA animation:
http://www.vukcevic.talktalk.net/SSW2012-13.gif
It should be noted that no single event of winter stratospheric warming has been recorded in the Antarctica during satellite age, due to lack of activity of the area’s single atmospheric volcano, Mt. Erebus.
None of the above appear to be directly linked to the solar activity as expressed in the SSN data, but in the N. Atlantic the tectonic activity does have some correlation to the SSN, particularly strong since 1880, the latest period of the more accurate data availability:
http://www.vukcevic.talktalk.net/SSN-NAPa.htm
Please elaborate on this ‘jet stream’ everyone talks about, as I do not see any such ‘fixed feature’ detailed on the weather synopsis maps.
One may view *changing* upper level conditions (wind and pressure contours) over time for CONUS here for instance:
http://weather.rap.ucar.edu/upper/
Or view the water vapor imagery depicting air mass movements as viewed from a postion over the North Pole:
http://www.meteo.psu.edu/~fxg1/SAT_NHEM/animwjap.html
One may observe “ANIMATION of Jet Stream Analyses” here:
http://squall.sfsu.edu/scripts/nhemjetstream_model.html
I ask again, where is this fixed feature, the ‘jet stream’ appearing?
.
David
Have you tried wiggle matching of solar cycles ?
We are currently 11 years since the end of the last solar maximum period of sunspot cycle #23 with the year of 2003 which had 104 sunspots . This was part of a long solar cycle of #23 which lasted about 12.6 years. Global temperatures started to drop about 2004/2005 and the winters were quite cold in 2008, 2009, 2010 and 2013. Looking back at similar historical solar cycle developments, we can compare 2013 with 1801 or 1873 when we also had 11 years without any major sunspot years and there were longer solar cycles involved, like solar cycle #4 which lasted 13.6 years and solar cycle # 14 which lasted 11.7 years. Global climate tends to drop at the end of long solar cycles and also during the early part of the decade following. One can see the global temperatures decline at the end and also after most long solar cycles like after cycles # 9,13,14,20. However if the next solar cycle or cycles continue to be low also as they did after # 4 and # 11 , then lower global temperatures may continue for decades there after . This may be the case for the next several decades if the current solar cycle #24 and the next, namely # 25, and 26 continue to be all low as some are predicting. . Global oceans STT have been now flat for 16 years and are now showing a decline since 2005. Global cooling seems to be indicated .
herkimer says:
June 20, 2013 at 5:37 am
Have you tried wiggle matching of solar cycles ?
Exploratory research, such as wiggle matching, can sometimes be useful for developing a hypothesis. But, the problem with doing so is that once you’ve formed your hypothesis, you can’t use any of the data you checked for testing your hypothesis.
For this reason, I’m wary of doing too much wiggle matching, etc, in a field such as climate science, because we have such a shortage of useful long term climate records. Have you read Carl Wunsch’s 1999 essay on the pitfalls of overinterpretation of climate records? http://ocean.mit.edu/~cwunsch/papersonline/bamsrednoise.pdf
Re: kadaka (KD Knoebel) says June 19, 2013 at 5:23 pm
jai mitchell on June 19, 2013 at 3:51 pm
This seems to be a topic in the eco-press e.g. Environmental News Network (ENN) and others as of late:
(1) The Jet Stream and Greenland, Environmental News Network (ENN), Andy Soos
Published June 18, 2013 08:02 AM
http://www.enn.com/enn_original_news/article/46110
(2) Jet stream changes cause climatically exceptional Greenland Ice Sheet melt, Uni of Sheffield
“Research from the University of Sheffield has shown that unusual changes in atmospheric jet stream circulation caused the exceptional surface melt of the Greenland Ice Sheet (GrIS) in summer 2012.”
Published 17 June 2013
http://www.shef.ac.uk/news/nr/jet-stream-greenland-ice-sheet-melt-1.280360
Is there data out there to suggest that the 1740 event was a global/widespread Northern Hemisphere event or is the usual ‘Europe was the centre of culture at this time’ approach to life mean that warmer weather in Siberia, Alaska, Canada, Greenland etc wasn’t considered worthy of mention??
Not that a 1740-style event shouldn’t be taken extremely seriously, but one wonders whether there were analagous events in other places when the climate in Europe wasn’t grossly cold or was in fact particularly hot??
rtj1211 says:
June 20, 2013 at 6:18 am
Is there data out there to suggest that the 1740 event was a global/widespread Northern Hemisphere event or is the usual ‘Europe was the centre of culture at this time’ approach to life mean that warmer weather in Siberia, Alaska, Canada, Greenland etc wasn’t considered worthy of mention??
Well, herkimer suggests that it might have been, because 1740/41 also seems to have been a very severe winter in northeast U.S., at least. See his comment on June 19, 2013 at 6:15 am, and David Archibald provides an interesting link to weather records for the area from then on June 19, 2013 at 6:31 am
Ronan
I have not read the essay that you mention. I agree that wiggle matching has its limitations . I recall a couple of years ago someone matching SOI and GLOBAL TEMPERATURE anomalies successfully using wiggle matching and a lag factor of about 6 months . In the strict sense of the words I did not really use wiggle matching but tried to illustrate that somewhat similar solar conditions existed in the past as we have to day and there may be a correaltion that may apply today. I realize that correlation is not causation. Also although the exact mechanism is not yet understood, low solar sunspot numbers seem to correlate with low global surface temperatures especially when ocean and solar cycles are both in sync during like during declining or rising phases. Solar sunspot activity is at the lowest level since 1900. During the decades of 1880, 1890 and 1900 the average sunspot numbers [NSO] were 45.2, 55.1 and 42.6. During 2000 decade they were 49.6. During the last 10 years the average sunspot number was 29.3. When the average solar level drops to about 40-50, cooler weather seems to set in. Low solar cycles typically come in threes, so it is possible that low sunspot number may exist for several decades into the future .Typically these longer solar minimums are characterized by a long solar cycle followed by three low level sunspot cycles resulting in some 45 years of lower sunspot activity, like 1872 – 1917 and again 1790-1836. There are 11, 22, 70-80, 200 year and even longer solar cycles
For the UK to have sustained below average temps (especially in the winter), strong north-easterlies are the norm. That is, a strong, semi-permanent area of high pressure sets up in Scandinavia. This is turn drives very cold north-easterlies into the UK. I wonder if there is any historic information for Denmark and Norway that could be correlated with the UK data?
In reply to:
_Jim says:
June 20, 2013 at 5:29 am
William Astley says June 20, 2013 at 3:17 am
An abrupt cooling event for one or two years due to changes in the jet stream …
William:
The UK weather is strongly affected by the position of a Rossby wave (jet stream) or by weather patterns that block the Rossby wave. As the jet stream moves from west to east the prevailing winds are from west to east. The prevail winds is the reason why the winter temperature on the east coast of North America is roughly 10C to 20C colder than the west coast for the same latitude. It is also the reason why London’s (51.5N) average winter temperature is 5C compared to St. John’s Newfoundland (Canada) 47.6N average winter temperature is -5C. Cooling for one to two years can be caused a temporary mechanism that changes the direction of the Rossby wave or that blocks winds carrying warm air from the Atlantic.
https://www.google.ca/search?q=rossby+waves&biw=1920&bih=901&tbm=isch&tbo=u&source=univ&sa=X&ei=ARPDUbenAaGcjAK47oHgDQ&sqi=2&ved=0CDkQsAQ
The Source of Europe’s Mild Climate
http://www.americanscientist.org/issues/id.999,y.0,no.,content.true,page.1,css.print/issue.aspx
Is the Gulf Stream responsible for Europe’s mild winters?
http://www.atmos.washington.edu/~david/Gulf.pdf
Planetary cooling, not regional cooling, for 50 to 150 years is due to solar magnetic cycle modulation of planetary cloud by an increase in clouds 40N to 60N and 40S to 60S. Low level clouds cool the planet by reflecting more sunlight into space.
rtj1211
Your queation about the extent of the 1740 cold spell.
Here is how Wikipedia described the extent of the cold weather
“During the ramp up to the crisis in January 1740, the winds and terrible cold intensified, yet barely any snow fell. Ireland was locked into a stable and vast high-pressure system which affected most of Europe, from Scandinavia and Russia to northern Italy, in a broadly similar way.”
I already posted information about similar cold weather in the eastern United States as Ronan pointed out earlier.
The year 1740 had the second coldest winter ever in UK after 1684. The spring was the 9th coldest, the summer was 27th coldest and the fall was 3rd coldest. The entire year 1740 was coldest ever in 355 years. Yet the winter of 1963 was the third coldest ever , so UK has experienced a similar winter fairly recently The cold winters of 1947,1917,1940 ,1979 and 1929 were no that far behind . More recently December 2010, and the first 6 months of 2013 are more signals that colder weather may be coming to Europe . The problem is that UK is still not prepared for cold winters and any attempt to warn UK as David is doing here and many others are doing seem to go on closed government ears with the unreal “ fight global warming only” agenda . In my judgment the possibility of more sustained colder weather is real for Europe and the unprepared will be affected the most.
kadaka (KD Knoebel) says:
“SST’s at all-time record high off Northeast North America? Where’s Tisdale?”
There was a peak in 2010, but otherwise the trend is down since 2007:
http://wattsupwiththat.com/2012/07/03/tisdale-on-the-curious-northern-hemisphere-sea-surface-temperature-anomaly-patterns/
herkimer says:
June 20, 2013 at 6:49 am
If you’re looking for a solar connection between the 1740 and 2009-11 cold events, I’d probably start with considering the North Atlantic Oscillation (NAO), because:
1.) There seems to be an anti-correlation between winter temperatures in Europe/eastern U.S. and Greenland/Arctic, e.g., van Loon & Rogers, 1978 : http://dx.doi.org/10.1175/1520-0493(1978)106%3C0296:TSIWTB%3E2.0.CO;2
2.) A lot of groups (including many of the ones jai mitchell refers to, as far as I remember?) argue that the 2009/10 & 2010/11 cold events were regional events related to the strongly negative phase of the NAO or the related Arctic Oscillation, e.g., Cohen et al., 2010 : http://web.mit.edu/~jlcohen/www/papers/Cohenetal_GRL10.pdf
3.) … and some researchers argue that the NAO is influenced by solar and/or geomagnetic variability, e.g., Bochníček & Hejda, 2006 : http://dx.doi.org/10.1016/j.jastp.2004.07.014 (paywall, unfortunately!)
rtj1211 says:
“Is there data out there to suggest that the 1740 event was a global/widespread Northern Hemisphere event..”
I have direct astronomical evidence that the cold shots of Jan-Feb, May-June and Oct-Nov 1740 were caused by short term solar factors, so would have had to have a global impact.
herkimer says:
June 19, 2013 at 4:09 pm
“I looked at the CET ANNUAL TEMPERATURES which peaked at 10.47 C in 1733.You can check it on the Met Office data base HadCET mean.”
There is barely any cooling till from 1739. The CET average for 1730 to 1738 is 9.93, that does not get exceeded till from 1989.
Damn that CO2; it’s such a misleading gas!
This post would not seem to address my question; perhaps if you had made it clear that ‘jet streams’ appear as components to Rossby waves and Rossby waves appear to be affected by and also ‘effect’ weather systems on their own it would have amounted to a good start …
.
herkimer says:
June 20, 2013 at 5:37 am
It looks like there is no correlation what so ever with solar cycles in this case. And there is nothing in the Be10 record. My guess is that the most likely culprit is the Ap Index. The Ap Index tracks the solar cycle generally most of the time. Back in the 1970s though there was a significant positive divergence. Presumably there can also be a significant negative divergence. It is time to look at the Ap Index in detail and look for a change in character.
David Archibald says:
“The Ap Index tracks the solar cycle generally most of the time.”
There is often low Ap index close to or at maxima, and in the first 1-2yrs from minima. Look through CET and see the amount of very cold winters within a year of solar cycle maxima.
David
I tend to agree that I cannot find any specific solar event connection to the 1740 cold event unless solar events cause extended negative AO type of conditions that lasted for about a year.
What I was trying to say howvere is that colder winter events will happen 2 years from now not for the reasons that you suggest with wigggle matching but for different solar reasons . By 2015 we will have had 13 years without major solar activity such as during 2000-2003 maximum . In the past when there was such a long pauses in major solar activity , winters were colder more often.Like after1801 and after 1883. I have no feel on how cold it might get.
herkimer says:
“..I cannot find any specific solar event connection to the 1740 cold event unless solar events cause extended negative AO type of conditions that lasted for about a year.”
This NAO reconstruction indicates the colder periods from Jan, May and Oct that I mentioned earlier. ftp://ftp.ncdc.noaa.gov/pub/data/paleo/historical/north_atlantic/nao_mon.txt
And again, there many very cold winters at solar cycle maximums because there’s often a drop in the Ap index there.
The utterly cold year of 1740 in Northern Europe was associated with the massive 1739 eruption of Mt. Hekla in Iceland, killing 10,000 islanders equivalent to 20% of Iceland’s entire population.
So, do book your 2015 summer holiday with confidence!
@ Jens Kieffer-Olsen
Wikipedia lists no eruption in 1739:
http://en.wikipedia.org/wiki/Hekla
Nor at Oregon state archive
http://volcano.oregonstate.edu/vwdocs/volc_images/europe_west_asia/eruption_history.html
I think you are confused.
Check out this link: http://runeberg.org/univers/0476.html
(Sorry it’s in Swedish.) It describes the 4 months long eruption of Mt. Hekla in 1739.
DMarshall says: Does that have anything to do with the extremely warm temps in Alaska right now or is that a separate phenomenon. I’ve heard reports of temps ranging from 82 – 98 degrees across the state after having unusually cold temps until just recently.
I am in Alaska right now and actually, the weather is pretty normal–the last few months were colder than usual and June has been just a little above average–very little: http://tinyurl.com/k7uelco
I was here in the late eighties and early nineties and it was remarkably good weather then, I could not believe how sunny and beautiful the summer days were. for YEARS,
The last few years have been rainy and cold and dreary. Horrible weather that the local news doesn’t really report because we rely on tourism. But the nice weather is just that, nice weather and nothing unusual. In other words, the few hot days we have had is not “extremely warm.” It is the weather we had in the late eighties and early nineties.
PS-I’m a Marshall too.
Fascinating. Major eruptions of a major volcano only attested in one old (1914) Swedish text.
Here’s part of the text in Swedish:
“av vars 23 verksamma vulkaner det 1500 m hoga Hekla ar den mest bekanta:
Ett av de valdsammaste utbrott man kanner pa Island intraffade 1739, da lavastrommarna fyllde
Skapt-ons och Herrfirflojts dalar till en maktighet av 125-190 m. och nadde den ena 84, en annan 34 kms langd samt under sina till 12-15 kubikkilometer uppskattade, stelnade massor begrovo 500 kvadratkilometer landyta.”
Here’s how Google translates it (not that well), with a couple of obvious adjustments:
“of the 23 active volcanoes, the 1,500 m high Mount Hekla is the most familiar:
One of the men feel parish pillars (?) outbreak in Iceland occurred in 1739, of lava streams filled
Skapt-ons and Herrfirflojts valleys to a thickness of 125-190 m, reaching one 84, another 34 kms length and during their 12-15 cubic kilometers appreciated, solidified masses buried 500 square kilometers.”
Some in the know think Hekla is about to blow now:
* http://volcanocafe.wordpress.com/2013/04/29/countdown-to-hekla/
Should Hekla erupt and cause a similar temperature drop as 1740, my jaw will be on the floor.
As it is indeed suspicious with only one source pointing to Mt. Hekla erupting in 1739, I asked a friend in Iceland for validation. He pointed me to the complete list ( in Icelandic ) of volcanic activity on the island: http://is.wikipedia.org/wiki/Eldgosaannáll_Íslands
This source mentions exactly the same locations Skaftá and Hverfisfljóti in the context of Laki erupting in 1783 as does Oscar Heinrich Dumrath in his description of an eruption of Hekla 1739. My conclusion is that Dumrath has gotten himself confused or was misinformed when he published his book in 1914. There was no eruption in 1739 in Iceland. – Project Runeberg makes available scholarly books from long ago, but doesn’t correct errors and typos on the fly 🙂
As I don’t subscribe to the idea of the temperature spike of 1740 being a ‘natural’ one, I wish to draw attention to the major eruption in 1739 of Mt. Shiveluch, also known as ‘The Bad Boy of Kamchatka’: http://www.paleoglaciology.org/regions/Kamchatka/ShiveluchVolcanoEruptions/
Alternatively the culprit could be Mt. Shikotsu ( Tarumai ), erupting from Aug.19 to Aug. 31, 1739: http://volcano.oregonstate.edu/shikotsu
Jens Kieffer-Olsen says:
June 25, 2013 at 10:45 am
————————————-
Would the climatic effects of those two NW Ring of Fire eruptions fall outside the background of ordinary annual volcanic activity?
That’s a good question. In my impression behind negative temperature spikes with a duration of one or a couple of years you eventually may identify an angry volcano. We know that Tambora caused the ‘Year without a summer’ in 1816, but which one caused the Great Frost of 1740 or any other Great Frost of long ago is not so obvious. It seems though that Mt. Shikotsu could be partly to blame. Quoting from page 52 of:
http://www.geos.ed.ac.uk/~studhope/Recent_Publications/D'Arrigo_et_al_2008_Nature_Geoscience.pdf
“[…] minor cooling follows the Shikotsu, Japan, eruption (1739, -0:33 C, VEI 5)”.