Missing the Missing Summer

Guest Post by Willis Eschenbach

Since I was a kid I’ve been reading stories about “The Year Without A Summer”. This was the summer of 1816, one year after the great eruption of the Tambora volcano in Indonesia. The Tambora eruption, in April of 1815, was so huge it could be heard from 2,600 km away (1,600 miles). The stories were always about how the following summer was outrageously cold. Supposedly, the summer was so cold it was like having no summer at all.

Being a suspicious fellow, I got to thinking about that, and I realized I’d never seen any actual temperature data for the year of 1816. So I went off to find some early temperature data. I started with the ECA dataset, and downloaded the Daily Mean Temperature TG (162Mb). That revealed five stations with daily temperature records with starting dates before 1816—Stockholm, Bologna, Milan, Praha-Klementinum, and Hohenpeissenberg.

So once again, I found myself playing “Spot the Volcanoes”, as in my previous post on this subject. When I wrote that post, I hadn’t been able to spot the smaller eruptions of Pinatubo and other modern volcanoes, but Tambora was the big cheese, the grand gorgonzola of volcanoes. Surely I could find that one … so here’s the record from Stockholm.

Figure 1. Two ten-year periods from the early 1800’s in Stockholm

So the question is, which year is “The Year Without A Summer”? The year indicated by the blue arrow, or the year shown by the green arrow?

Actually, I fear that was a trick question. Here’s the same data, this time with the years indicated.

Figure 2. Two ten-year periods from the early 1800’s in Stockholm, including the dates.

As you can see, the “Year Without A Summer” actually was warmer than a number of other summers in Stockholm. It’s the third peak from the left in the top panel, and was above 20°C. Just in this tiny sample we see some six summers that were cooler than the summer of 1816 in Stockholm …

So, I looked at the other locations. Here are the other four European cities with records that cover the Tambora eruption—Bologna, Milan, Praha-Klementinum, and Hohenpeissenberg. In these, both the upper and lower panels are from the early 1800s. No more trick questions, in all cases, one or the other of the green and blue arrows actually indicates the “Year Without A Summer”.

Figure 3. Two ten-year periods from the early 1800’s in Bologna.

Figure 4. Two ten-year periods from the early 1800’s in Milan.

Figure 5. Two ten-year periods from the early 1800’s in Praha-Klementinum.

Figure 6. Two ten-year periods from the early 1800’s in Hohenpeissenberg.

That was all the daily temperature records I could find from that far back. There’s a monthly record from Armagh, in Ireland. Here’s that record.

Figure 6. Two ten-year periods from the early 1800’s in Armagh.

I’m sure that you can see the difficulty. If Tambora actually did something to the temperature, you sure couldn’t tell it from these records. Not one of them is readily distinguishable as missing a summer.

In “The Great Tambora Eruption in 1815 and Its Aftermath” (paywalled, Science Magazine, 1984), the author says (emphasis mine):

To Europeans and North Americans, 1816 became known as “the year without a summer” (41). Daily temperatures (especially the daily minimums) were in many cases abnormally low from late spring through early fall; frequent north-west winds brought snow and frost to northern New England and Canada, and heavy rains fell in western Europe. Many crops failed to ripen, and the poor harvests led to famine, disease, and so- cial distress, compounded by the aftermath of the Napoleonic wars.Tambora’s dust veil is often blamed by modern researchers for the cold summer of 1816. The argument given is that the stratospheric dust veil would have absorbed or reflected solar radiation that could otherwise have reached the ground (42). Not all regions,however, experienced abnormally low temperatures, and the preceding winter had generally been mild. Therefore, a few researchers deny that there was any (or at least a strong) connection with the volcano (39,43).

I’m leaning towards the “few researchers” that deny a strong connection with Tambora. What other records do we have? Well, over at KNMI I find the record for Manchester, England:

Figure 6. Two ten-year periods from the early 1800’s in Manchester.

Moving across the Atlantic, here’s the record from New Haven in Connecticut.

Figure 6. Two ten-year periods from the early 1800’s in New Haven, Connecticut.

I’m just not feeling the Tambora love here … where are the records of years without a summer? Or at least of a summer that’s significantly colder than its neighbors?

Don’t get me wrong here. I suspect that generally, the summer of 1816 was a bit colder than most summers. But as the graphs above show, in all of these datasets there are comparable summers within a few decades either side of 1816 that have summers that are as cool, or cooler, than the summer of 1816.

And I would guess that a careful search would reveal some records with cooler summers than the ones I’ve found here. But overall, let me suggest that over the years the Tambora story has gotten greatly exaggerated, just as we do today with our stories of “Cold? You haven’t seen real cold. Why, when I was a young man it was so cold that …”

Conclusions? Well, my main conclusion is what I’ve been saying for some time. The temperature of the earth is not particularly ruled by the changes in how much energy it receives. Tambora cut off a huge amount of sunlight, but the effect was small. Yes, some areas had a summer that was a bit cooler than most summers. And I’m sure there were certain locations where it hit harder than others. But overall? The thermostatic mechanisms of the planet kept Tambora from having a much of a cooling effect.

My best to all. I append all of the figures below, with the dates, so you can see the lack of effect. Note that in many of them, the temperature in 1815 was about the same as 1816 … and that despite the size of the volcano, if there was any effect, it was totally gone by 1817.

w.

If that’s what a really big volcano can do, I’m not impressed. Well, I am impressed, but what’s impressive is the strength of the thermostatic mechanisms that keep the earth’s temperature within a very narrow band. Even a huge volcano can’t put it out of sorts for much more than one summer, and even then not too much.

[UPDATE] Someone in the comments said:
The place to look for the effect of volcanic eruptions on the climate is in food commodity prices. That is where climate change has its greatest impact on human society. In those records the Tambora eruption is unmissable.
John West in reply pointed to a great study of historical UK food prices, The Price History of English Agriculture, 1209-1914. From that study …
If the effect of Tambora is greatest in food commodity prices, well, the prices in 1816 were the lowest in the entire decade, so do we need more volcanoes?
As I have said more than once, the effect of volcanoes (and by implication the effect of changes in forcing in general) on temperature is vastly over-rated.
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Warren in Minnesota

These graphs were daily mean temperatures. Are there daily minimum temperatures that could be plotted over decades?

Nat Whilk

Your intended trick question isn’t a trick question, since the dates are present in Figure 1.
[REPLY: Grrrr … proofreading 10 different graphs, the title was right but the contents wrong … fixed, in any case, and thanks. -w.]

Tom Ragsdale

A small point but Fig 1 and Fig 2 both have dates.

newtlove

Let’s accept the above as true, “Even a huge volcano can’t put it out of sorts for much more than one summer, and even then not too much.”
Now let’s consider the recent papers that stated that a period of intense volcano activity initiated the last ice age. Hmmm… using a quick Onager estimate, the whole earth must have been erupting, and did so for several centuries, for huge glaciation to have occurred for over 100,000 years.

PJ Brennan

pretty amazing, really. Really illustrates how susceptible we are to myths and exaggeration about weather and climate. Thanks Willis, impressive as always.

polistra

I wondered if the real difference was in precipitation?…. Sometimes people tend to mistake unusually wet for unusually cold and vice versa. For instance, this winter in Spokane was strictly average for temperature but abnormally dry and unsnowy. All the media have been calling it warm and mild.
But no. A quick look at the Klementinum data shows a nice period of strictly average precip around 1816!
http://www.climatestations.com/images/stories/prague/prgprcp.gif

Sandy

What do the tree-rings say?

the1pag

The oceans, being a gigantic heat sink, both store and release heat.

Dr. Science

Have these data been processed thorugh Mann and Hansen’s disgronificator? We can’t know what the temperatures actually were until we decide what we want them to have been… (that verb tense is what I call the “past superfluous”).

Interesting indeed! Especially interesting in considering arguments that volcanic eruptions can sustain global cooling for long periods of time, including whole glacial periods in the past. Volcanic eruptions are short, punctuated events, not well suited to generating and sustaining long glacial periods. Although this one example is probably typical, similar data on other large eruptions would be nice. What Willis has shown in this example is the kind of real evidence needed to demonstrate whether or not volcanic activity is a viable cause of long-term climate change, as claimed by a number of recent publications.

Allen63

Based on this “history” — maybe it really was the “low” temperatures on a relatively few key summer days in “sensitive” locations that lead to the stories regarding the year without a summer. I read it snowed in June in Ohio. I also read this:
“In April 1815, Mt. Tambora, .. exploded…
In some parts of the world, the impact was minor but in much of Europe it caused near famine conditions. In New England it helped change history…
Several cold spells in May 1816 delayed the start of the planting season. June began well, but crops were lost in a cold spell between the 5th and 11th. Snow accumulated throughout all but southernmost New Hampshire. A warm spell starting the last third of June provided hope that summer had arrived, but a killing frost on July 9th dashed that hope. The rest of the month was warmer, but didn’t equal the warmest days of June. A warming trend in August abruptly ended with frost on the 21st and a worse one on the 30th. …
After 1816, the weather returned to normal conditions quickly. However, farmers had already started emigrating to the more hospitable weather and soil of Ohio and further west…”

izen

What this demonstrates is just how fragile our agricultural system has been to quite small climate changes.
As the graphs show the difference between a good and bad year can be just a degree or so, hardly perceptable on a graph of several decades and apparently not much different from other years without the influence of a volcanic cooling event.
The place to look for the effect of volcanic eruptions on the climate is in food commodity prices. That is where climate change has its greatest impact on human society. In those records the Tambora eruption is unmissable.

There was a series of large volcanic eruptions starting in 1812, so a comparison with pre-1812 temps would be appropriate. In Europe and China the main effect was heavy rain and lack of sunshine causing crops to fail. Indicating aerosol seeded clouds were the main effect.
The unusual cold in eastern N America might have been a consequence or it might just have been coincidental.

Stephen Wilde

Must be something to do with atmospheric pressure ??

I’m going to reply before I read the full post. I don’t think I’ll be too far afield, if so I’ll do a followup.
I’ve written a web page titled 1816: The Year without a Summer A New Hampshire Perspective. I think New England is where the phrase came from, we ceratinly can take credit for “Eighteen Hundred and Froze to Death.”
First a correction. You say “The Tambora eruption, in April of 1815, was so huge it could be heard from 2,600 km away (1,600 miles). That was the Krakatoa eruption in 1883. There were a lot more Europeans in Indonesia then and the telegraph communications helped get the news about Krakatoa’s explosion to Europe much more quickly than the Tambora eruption. (I wouldn’t be surprised if Krakatoa were louder too. I doubt loudness correlates all that well with material and SO2 released.)
Second, the summer of 1816 wasn’t cold all the time. It was very cold some of the time. I concluded that the major effect was that the norther jet stream didn’t migrate as far north that summer as usual. For example, I note:

Several cold spells in May 1816 delayed the start of the planting season. June began well, but crops were lost in a cold spell between the 5th and 11th. Snow accumulated throughout all but southernmost New Hampshire. A warm spell starting the last third of June provided hope that summer had arrived, but a killing frost on July 9th dashed that hope. The rest of the month was warmer, but didn’t equal the warmest days of June. A warming trend in August abruptly ended with frost on the 21st and a worse one on the 30th.

The apple crop did quite well due to the lack of insects. That means the blossom managed to miss a freeze, so even in the spring there were stretches of frost-free weather.
Further south, the agricultural impact in Virginia was minor. They would have missed out on the frosts in pretty much any event, but what I recall from my readings was that people’s journals didn’t have much to say about the summer being abnormal.
There were also significant impacts in Europe, but I’m not so conversant about them. One piece of triva – Mary Shelley wrote her novel Frankenstein during her vacation to Switzerland in 1816 when the weather was so inhospitable that she and her friends spent little time outside. http://www.atlantisjournal.org/ARCHIVE/28.2/2006Phillips.pdf is worth reading.

Apparently the climate mechanisms are watching over us, instead of we (humanity) influencing on a global scale the climate. How fortunate we are to live on earth!!

Why so many graphs without any dates??
And the two first wher one is supposed to have no dated, both graphs have dates…
Why not simply show one copy of each graph, with proper dates? It would be easier to follow.
Other than that I remember reading about “The Year Without A Summer” in Scientific American some ~30 years ago… I was fascinated. If it was all wrong, I am fascinated again…

Darkinbad the Brightdayler

Perhaps you need to look beyond temperature as the sole arbiter of what makes a summer.
Sunshine hours? Crop failures, cold spells that cause them? storms?
As I recall,last year or the year before in the UK was forcast to be a “Barbeque Summer” a dismal non-event.
There may have been a gap between expectations and actualities that wasn’t tied to one factor.

Baa Humbug

On a clear sky day with the sun beating down on my red neck, it gets quite hot here in Brisbane. But it cools down nicely by evening when I enjoy a nice cold beer on the verandah.
During an overcast day the temperature never reaches the heights of the clear sky day. However the nights can be warm and stifling, difficult to sleep.
How does one determine the above from mean Ts?

As a professional geologist I am greatly impressed by large volcanic eruptions. However, that impressiveness has no relation to climate. As a professional photographer I look forward to the heavy duty red sunrises and sunsets too. That too may be atmospheric but not related to climate. Willis is most correct when he points out, in different terms, that we humans choose
the mythology we believe. That mythology may or may not have any relationship to reality and over time that relationship seems to disappera all together. I grew up in a small town north of Madison, Wisconsin. Yes when I was a boy not only was it coooold but we had way more snow. Thinking about it, my butt was way closer to the ground too.

JohnG

If one looks at the CET data ( http://mclean.ch/climate/England_Scotland.htm )
it shows a down spike of around -1.6ºC for 1816, which is nothing like the down spike for 1740 of about -2.7ºC or the one of 1880 of -2ºC
http://mclean.ch/climate/Eng_Scot/Fig_02_CET_anomaly.gif

Nylo

Willis, it is true that 1816 was just a case of “one more cold summer”, and not a really, really cold summer anywhere, but the big difference is that this cold summer happened in all places, while normally, if somewhere in the world is particularly cold, it is because it is hotter in other parts. Tambora made the weather everywhere agree that it was cold, so to say. Not to mention that there may have been places where it was actually extremely cold and we just don’t have the records.
Why don’t you plot the average temperature of all the records that you have for all the years? I mean, something like a “global” temperature of the few records you have. You will probably find Tambora there, shouting out loud. If it doesn’t appear there, then I will have to agree with you.

P.F.

If you are looking for the effects of a really big volcano, try the Toba event around 74,000 ybp. The Sunda event (around 535 c.e.) was a fun one too. David Keys has an exellent study on the effects of Sunda in his book, Catastrophe. It was also made into an episopde in a series for PBS called “Secrets of the Dead.” That series included a good segment on the demise of Norsemen in Greenland as the LIttle Ice Age set in. But come to think of it, with all the seismic activity in Indonesia lately, I wonder if we’re due for another pyroclyastic event on par with Tambora or Krakatoa.

HADCET: http://www.metoffice.gov.uk/hadobs/hadcet/mly_cet_mean_sort.txt
out of 353/354
1816
Coldest July ever
20th coldest August
26th coldest June
38th coldest May
50th coldest April
34th coldest September
238th coldest October – the outlier
23rd coldest November
11th coldest December
1817
3rd coldest May
15th coldest July
10th coldest August
2nd coldest October.

John S

Just in this tiny sample we see some six summers that were warmer cooler than the summer of 1816 in Stockholm …
[REPLY: Thanks, fixed. -w.]

Must be something to do with atmospheric pressure ??
Or ocean – atmosphere heat gradient. The global average near surface atmospheric temperature is a bit less than 2C cooler than the average ocean surface temperature. Reduce the atmospheric temperature by say 0.5C and more heat transfer to the atmosphere through evaporation, and more clouds and rain.

Philip Bradley says:
April 15, 2012 at 7:59 am
There was a series of large volcanic eruptions starting in 1812, so a comparison with pre-1812 temps would be appropriate. In Europe and China the main effect was heavy rain and lack of sunshine causing crops to fail. Indicating aerosol seeded clouds were the main effect.
10Be is deposited by adhering to stratospheric aerosols which then drift down and rain out over the next 1-3 years. The amount of aerosols in the stratosphere is controlled mainly by volcanic eruptions. There were such strong eruptions in 1693 (Hekla on Iceland, having large effect on nearby Greenland), 1809 (see Dai JGR 96, 1991), 1814 (Mayon), 1815 (Tambora), 1883 (Krakatoa), 1964 (Agung).
So, large volcanic eruptions have a signature in the 10Be concentration in polar ice. That concentration [caused by spallation of nitrogen by cosmic rays] is also used as an indicator of solar activity so the activity record is contaminated by volcanism. You can see that in the 10Be record from Greenland [ http://www.leif.org/EOS/2009GL038004-Berggren.pdf ]. Here is a blowup of the upper panel of their Figure 3 that shows the 10Be concentration with yearly resolution: http://www.leif.org/research/10Be-NGRIP.png little colored dots show the peaks in 1695, 1813, 1817, and 1966. There is also a peak for Krakatoa, and strong peaks back in 1436 and 1460 [possibly matching eruptions back then]. Of course, there are also numerous other peaks and not all ice cores show all the peaks, so local effects of weather and precipitation also play a role. So, volcanoes may not do much to global temperatures, but certainly louse up the record of cosmic rays determined from 10Be. BTW, it is interesting that the total global production of 10Be is only 2 ounces per year, so it is remarkable that we can measure what is deposited in an annual ring in a an ice core 4 inches across.

David Loufek

izen writes “The place to look for the effect of volcanic eruptions on the climate is in food commodity prices. That is where climate change has its greatest impact on human society. In those records the Tambora eruption is unmissable.”
Possibly so; do you have the charts and can post?

Hutch

I picked up a bound copy of the issues of the (London) Monthly Magazine for the latter half of 1816 at a book sale many years ago. Here are selected bits of the weather and agricultural reports for July (MM, No. 288, p. 73):
Meteorological Report
Average temperature in London (Covent Garden), July 1816: “53.7 of Fahrenheit” = 12.1°C., rainfall “about 4 inches” (~100 mm)
cf. 1971-2000 normals (Greenwich) July max=22.5°C, July min=12.0°C, rainfall=40 mm.
Monthly Agricultual Report:
“The variable spring seasons, and late successive rains have been this year common to both Europe and America, and the corn crops are probable in consequence, to be universally affected. Much of the wheat in Poland has been destroyed, and great part of Germany and Belgium devastated by floods and storms. In France the crops have escape more favourably. So backward a season has not been experienced in this country since the year 1770.”
So midsummer in southern England was apparently somewhat cooler and much wetter than normal, and wet conditions were obviously fairly widespread across northern Europe. Rick Werme’s report (above) suggests that the poor harvests in New England were mainly a product of low temperatures. Was there a similar effect in the northern hemisphere post-Krakatoa?

Espen

Really interesting stuff! I’ve long wondered if the net effect of large volcanic explosions is one of cooling at all, since the Pinatubo explosion after the initial cooling may have caused some decade-long slight tropospheric warming (by cooling the stratosphere).

EternalOptimist

Summer without a summer, is anectodal evidence. Obviously you have to very cautious, and W is right to check it out.
But I live in Manchester England. and it only takes 3c and a few clouds to turn a lovely barbeque day into a ‘where the heck has the summer gone’ day.
and it doesnt take many of those to produce the myth. It doesnt matter what the rest of the world did, we had a lousy summer.
So the anecdotes dont tell the full story, maybe the stats dont either

P.F. says: April 15, 2012 at 8:47 am
Interesting you should mention that. A google search of “Anak Krakatau” makes for fascinating reading.

Gail Combs

In the 1800’s most people were farmers or closely aligned to farmers. As Ric Werme said it was not necessarily the overall temperature of the summer but the killing frosts during the spring and perhaps the extra rain (SO2 + particulates) that wiped out harvests that would be associated in people’s minds as “without summer.” Most people/farmers think of summer as the sunny dry weather that ripens crops and drys hay. Sunshine also helps keep fungus from rotting the crops in the field.

…Gray-mold rot or Botrytis blight, caused by the wide-spread fungus Botrytis cinerea, affects most vegetable and fruit crops, as well as a large number of shrubs, trees, flowers, and weeds. The disease is favored by cool moist conditions and little or no wind…
The fungus causes primarily blossom blights and fruit rots, but can also cause damping-off, bud rot, stem cankers or rots, leaf spots or blights, bulb rots, and tuber or root rots. Botrytis is also a problem on fruits and vegetables in cold storage and subsequent shipment because the fungus is able to function at temperatures just above freezing. With some possible exceptions, Botrytis mainly attacks tender tissues (flower petals, buds, or seedlings), weakened or injured tissues, and aging (senescent) and dead tissues. Actively growing tissues, other than flower petals, are seldom invaded directly… http://web.aces.uiuc.edu/vista/pdf_pubs/942.pdf

Also if it was rainy the temperatures would be moderated. Lows not as low and highs not as high so the averages would not reflect people’s perception. Again the perception would be of a “cool” summer especially since damp weather seems colder to people.

anna v

Willis I would tend to believe the reports of the people who lived through it. This was not the first time this happened.
I think we have here a problem that the perception of a cold summer for humans and the plot of average temperature do not have much to do with each other.
Let me illustrate: the average summer temperature may be 20C, but if it is (16+34)/2 I would call it an air conditioned summer here an Greece: cool nights and pleasant for swimming days.
If the average comes from (40+0)/2 in a desert for example, I would call it pretty uncomfortable.
If it was cloudy all the time and it was (18+22)/2 it would be a disaster for agriculture, with little sun for ripening grapes etc. etc.
In my opinion the data that will show the problem of the volcano will be: wines , wheat production and similar data connected to human activity.
Of course your plots illustrate how irrelevant average temparature is with respect to the economic future.

P. Solar

Firstly I would agree that far too weight is given to volcanic “forcings”,. This is just used as a pretext to CO2 warming effect even further. If the significant volcanoes of late 20th c. did not produce the “expected” cooling this is just proof that the positive feedbacks on CO2 forcing are even stronger. “It’s worse than we thought!”. Note that Hansen’s volcanic forcing is stronger than anyone else’s.
One thing you can also look for is milder winters. That is one thing I noted a year or two back when I was looking the recent volcanoes as Willis did before. In the same way that cloudy whether gives cooler days and warmer nights the blocking effect of volcanic dust gives milder winters.Some of Willis’ graphs show this but not all.
The anecdotal report that Willis cites here also make mention of that.
However, it should be noted that this was not just one volcanic event. The decade leading up to Tambora was highly active and one should not be looking for a one year event.
Also crop yields were crippled by some very late frosts. It only takes one night of heavy frost to kill off all your wheat. Don’t expect to see that in a plot covering 10 years.

Scott

You need daily minimum temps, and timing as to months (was the smmer short and late) etc. Again, Will does a very simplistic analysis while trying to refute a more robust analysis. Pretty poor science, and shallow thinking. You would never have gotten a degree from my lab…

I tend to go with the reports from Vermont at the time where frost continued into June and it snowed in July. Not everyday was colder than normal, and the whole average wasn’t necessarily colder than normal, but there were some very cold days indeed.

William Astley

Thank-you Willis for the very interesting piece. The data unequivocally supports your conclusion.
The observation that the largest volcanic eruption in modern history had a very minor and short lived effect on planetary temperature supports Lindzen and Choi’s data and analysis that the planet resists forcing changes rather than amplifies it.
As most are aware the IPCC’s general circulation models assume there is positive feedback which amplifies the CO2 forcing. If planetary clouds in the tropics increase which reflects more sunlight off into space thereby resisting warming (negative feedback) the planetary warming due a doubling of atmospheric CO2 will be less than 1C with most of the warming occuring at hight latitudes which will cause the biosphere to expanded and will result increased crop yields in Canada and Russia due to an increase in frost free days.
http://www-eaps.mit.edu/faculty/lindzen/236-Lindzen-Choi-2011.pdf
On the Observational Determination of Climate Sensitivity and Its Implications
Richard S. Lindzen1 and Yong-Sang Choi2
We argue that feedbacks are largely concentrated in the tropics, and the tropical feedbacks can be adjusted to account for their impact on the globe as a whole. Indeed, we show that including all CERES data (not just from the tropics) leads to results similar to what are obtained for the tropics alone – though with more noise. We again find that the outgoing radiation resulting from SST fluctuations exceeds the zerofeedback response thus implying negative feedback. In contrast to this, the calculated TOA outgoing radiation fluxes from 11 atmospheric models forced by the observed SST are less than the zerofeedback response, consistent with the positive feedbacks that characterize these models. The results imply that the models are exaggerating climate sensitivity.

anna v

Sorry, my arithmetic is faulty 16+34/2 is 25c. It should be something like 12 +28/2 that would be the air conditioned summer with average 20C, but the point remains the same

John West

izen says:
“The place to look for the effect of volcanic eruptions on the climate is in food commodity prices. That is where climate change has its greatest impact on human society. In those records the Tambora eruption is unmissable.”
Please provide a reference. England doesn’t seem to have noticed in their food prices:
Year……Wheat……Rye……Barley…..Oats……Peas……Beans…..Potato……Hops…….Straw
1810……13.05…….7.43……5.83…….3.47……6.89…….6.75……..3.15……..124.85…..57.67
1811…….11.73…….5.66……5.12…….3.34……5.81……..5.83……..3.01……..173.13…..70.75
1812…….14.38……9.18…….8.09……5.39……8.31……..8.49……..4.24……..150.15…..56.42
1813…….13.46……9.59…….7.09……4.67……9.91……..9.74……..5.2……….262.79…..40.83
1814……..9.68…….5.97…….4.53……3.11……6.54……..5.75……..3.3……….198.55……42.33
1815……..8.14…….5.08…….3.67……2.86……4.97……..4.57……..3.3……….186.35……35.75
1816……..8.89…….5.09…….4.11…….3.29…..4.44……..3.95……..3.48……..220.02…..44.04
1817…….12.16…….6.95…….5.98……3.93……6.33……..5.77……..3.97……..340.82……39.12
1818…….10.82……6.84…….6.53…….3.93…..5.91……..7.24……..4.04……..305.13……50.5
1819……..8.84…….6.98…….5.55…….3.42…..6.68……..7.42……..4.18……….91.43……58.17
1820…….8.26……..5.2………4.1……..2.93……5.11……..5.41……..3.57………..78.62…….31
Source: http://www.econ.ucdavis.edu/faculty/gclark/papers/Agprice.pdf

JackM

It seems to me that there are 2 issues being discussed here. 1. Was the period 1816-1817 abnormally cold, especially in North America? (meaning freezing people, killed crops etc.) 2. If there was an abnormality was it caused by vulcanism? Searching “1816 year without summer:” find many links which do support the below normal temperature historical record. So I for one, even though a sceptic, accept that. The above graphs do not seem to agree, hence the vulcanism issue is not relevant. Question: do we have any reason to believe in the accuracy of the temperature records? I read that even the temperature histories from the mid 19th century are suspect, some were read from thermometers which were inside of buildings.

Chuck Nolan

“So the question is, which year is “The Year Without A Summer”? The year indicated by the blue arrow, or the year shown by the green arrow?”
———————————————————————–
Willis
You might want to scrub the dates from figure 1.
Not much of a quiz, otherwise.

Arno Arrak

I repeat what I said about Dronning Maud etc. on Friday:
“If this proves anything it is that volcanic eruptions just don’t measure up to their reputation. I have come to the conclusion that volcanic cooling that is supposed to follow an eruption and have an influence on climate simply does not exist. Part of it is due to ignorance of the fact that all climate graphs at all times are full of El Nino peaks and La Nina valleys in between. Those are the spikes they try to eliminate by their running averages. It so happens that when a volcano erupts when an El Nino has just peaked and a La Nina valley is beginning to form that La Nina valley is recruited as an example of volcanic cooling happening. Two examples of this are Mount Pinatubo and Gunung Agung. On the other hand, when the eruption takes place when the La Nina has bottomed out and the next El Nino is just beginning the expected cooling is simply absent and nobody has any idea where it went. El Chichon in Mexico is an example of that. Whether a cooling can be observed after any particular eruption thus depends upon the timing of the eruption with respect to the location of neighboring El Nino and LacNina phases of ENSO. This of course is contrary to claims that volcanic cooling can ovecome El Nino warming as so-called “experts” have been telling us. For more info read pages 17-21 in What Warming?”
On the scale you show here the ENSO oscillation cannot be seen but I see a distinct jiggle that may contain El Nino peaks if expanded. It is worth it to print it out in full and try to check out Tambora’s timing with reference to the ENSO oscillation. Bimonthly resolution that HadCRUT3 uses ought to show it.

Kyle K

Should the effect of Tambora be in question, or the temperature record?

Detailed description of 1816 New England and Quebec weather.
http://www.islandnet.com/~see/weather/history/1816.htm

Tim Clark

[izen says:
April 15, 2012 at 7:59 am
What this demonstrates is just how fragile our agricultural system has been to quite small climate changes.]
No.
What this illustrates is the huge affect an insignificant cooling has on Mankind. One degree warmer hasn’t fazed us a bit.
Think about that.

Scott

The real question is not how did volcanic eruptions affect one summer, the question is how did they affect the Little Ice Age and the cold temps during the Maunder and Dalton minima. If you can overcome the argument that the cooling during those periods were not volcanic induced then you are talking and may have something. That is very difficult to do though.

Kasuha

Uncorrected temperatures (without annual cycle removed) are usually very deceiving, as most of values lie on rather steep slope hiding most of differences. You basically see four out of twelve months in a year. Next time you feel like playing this little game I’d appreciate if you removed the annual cycle.
Now I’m not saying it’s all hidden in there. I did not analyse the data this way and am not going to. My bet is rather on other, non-temperature related phenomena. It’s known fact that volcano eruptions cause bright red sunsets which may be perceived negatively by many people. There’s also slight atmospheric shading effect caused by large volcano eruptions – people don’t really see that the brightness has changed and temperature doesn’t really change as well, yet they have feeling of impeding doom and feel colder.

Gary Pearse

Hutch says:
April 15, 2012 at 8:58 am
“…(London) Monthly Magazine for the latter half of 1816 …..selected bits of the weather and agricultural reports for July (MM, No. 288, p. 73):”……….The variable spring seasons, and late successive rains have been this year common to both Europe and America, and the corn crops are probable in consequence, to be universally affected. Much of the wheat in Poland has been destroyed, and great part of Germany and Belgium devastated by floods and storms…”
And we want to knock the temperature down 2C+. Is this the “new world order” utopia?

Scott

This is actually funny, from Mr. Bradley’s link:
“Of the cold summers in the period 1811 to 1817, the year 1816 has gone down in the annals of New England history as “The Year There Was No Summer,” the “Poverty Year” and “Eighteen Hundred and Froze to Death.” The year began with a moderate but dry winter. Spring was tardy and continued very dry. The growing season from late spring to early fall, however, was punctuated by a series of devastating cold waves that did major damage to the crops and greatly reduced the food supply. In areas of central and northern New England, the summer had only two extended periods without frost or near freezing temperatures. A widespread snow fell in June. As a result, corn did not ripen and hay, fruits, and vegetables were greatly reduced in quantity and quality.”
So the year without a summer may have had near normal averages, it was the unexpected cold waves that killed crops that got it the name. Maybe Will should do some research on the null hypothesis before he posts, as this post is irrelevant to the question if the link is correct.