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 1816 “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.
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.
Eyal Porat says:
April 15, 2012 at 9:37 am
Thanks, Eyal. In fact, the winters of 1889-90, 1904-05, 1910-11, and 1948-49 were all colder in Jerusalem than the winter of 91-92. Also, the surrounding fall, spring, and summer were all unremarkable. This makes it more likely that the winter of 1991-92 was, like the even colder winter of 1948-49, a natural event rather than one caused by Pinatubo.
The problem is that when there is a volcano, everyone thinks the following weather is connected. It might be, but then again, it certainly might not be …
w.
P. Solar says:
April 15, 2012 at 9:39 am
You’re not following the story. The prices should have been highest in 1816, due to the bad crops. They weren’t. And even in 1817, the prices were lower than in 1810.
w.
This past winter in the Midwest US was extremely mild, yet global temperatures were a bit below the average (satellite era.) The reason for the lack of cold this past winter in the Midwest was a jet stream that almost never took aim on the Central US. Now in April, we are seeing more upper-level troughs, resulting in heavy rains and severe weather.
The point is that we don’t need a volcano, or any other disruption, to get occasional locks in the upper-level wind flow that will target a region with extreme weather for several months. It sounds to me that a persistent upper level trough was unusually locked into the Northeast US in the spring and summer of 1816, and the volcano had little, or perhaps nothing to do with it. If it did, wouldn’t the winters before and after the summer of 1816 be unusually cold as well, and wouldn’t the impact be global? We do not find any evidence of that in the records or the antidotes.
I think the real impact of this series of articles by Willis is the way they support the strength of natural climate variability and indicate the weakness of the man-made global warming theory. AGW, and the models based on it, assume that CO2 is the primary driver of global atmospheric temperature. One of the historic difficulties with this assumption is the mid-20th Century cooling that took place while CO2 was increasing rapidly. The only way the models work, is to blame aerosols from human pollution for the cooling. There was little scientific evidence that pollution aerosols could actually do that, but the idea was supported by the ‘supposed’ global cooling that followed large volcanic eruptions.
If large volcanic eruptions do not significantly reduce global temperatures, then it is unlikely that human produced aerosols do either!
Without the aerosol assumption, climate modelers will be forced to reduce the climate sensitivity to CO2 and increase the natural variability inherent in their models, to successfully hindcast the 20th Century.
Willis,
James Marusek has a couple PDFs of weather history at his site.
http://www.breadandbutterscience.com/Weather.pdf has a graph of Philadelphia monthly temperature differences for 1816 compared to the rest of the Dalton Minimum. 10 of the months are below that average with June being ~8F lower. Every month of that year had a hard freeze. It appears temperatures were very erratic that year and not consistently low. Perhaps due to uneven density of the volcanic ejecta?
He must have extracted them from the monthly chapters in the book named in his reference 1. Google has a scanned copy of it.
He also has a climate history by Douglas Hoyt which also talks about 1816.
http://www.breadandbutterscience.com/climatehistory.pdf
Willis Eschenbach says:
April 15, 2012 at 10:58 am
Yes, that page was indeed cobbled together. I do note near the end:
I don’t own the Stommel’s book.
Some of that section may have come from http://www.islandnet.com/~see/weather/history/1816.htm which is also a collection from other sources from Quebec to Virginia.
My goal was to add a New Hampshire centric web page about 1816 for the benefit of people interested in that subtopic (of either NH or 1816). Also, I felt that granite monument (I first heard about it in the Sci Am article) deserved a web presence. There is so much overlap in sources that it wasn’t worth making a more complete bibliography, though I am tempted to add sources I didn’t know about at the time like Brian Fagan’s “The Little Ice Age.”
Fagan does a good job tying 1816 to the neighboring years, e.g. “The subsistance crisis of 1816/1817, triggered by catastrophic harvest failures in 1816, was the last truly extensive food dearth in the Western world. Its effects ranged from the Ottoman Empire, to parts of North Africa, large areas of Switzerland and Italy, western Europe, and even New England and eastern Canada.” The next section starts with “The cold years of 1812 to 1820 coincided with a cycle of poor grain and potato harvests, food scarcities, and rapidly rising commodity prices in societies that were already unsettled by changing economic conditions at the end of the Napoleonic wars.”
I bought Fagan’s book after getting absorbed in it while visiting the library while my daughter was in a karate class. He has some others that may be worthwhile, though I think some have a bit of a AGW point of view.
“You can’t expect to just haul off, read raw data and have it to reveal truth. That data must be ADJUSTED!”
Yes, what are we thinking just looking at unadorned facts and unadjusted data???
Willis, please hand this post over to James Hansen so that he can properly adjust and filter it for public consumption.
/irony
MattN says:
April 15, 2012 at 11:27 am
You cite a web page by Ric Werme? That’s your evidence? I discussed his web page above …
w.
As a farmer that has grown crops for many years it is worth reminding everyone here that crops, or indeeed all plant life, need 4 things to grow. Nutrients, warmth, moisture and sunlight energy. Half of our farm is irrigated and half dryland. In a wet year the unirrigated part of the farm has higher than average yields because moisture is no longer the limiting factor. However wet years are usually cloudier and often in wet years our irrigated crops yield less than they do in dry years with irigation because the sunlight energy is then the limiting factor.
My view.
That, even though the temperatures were not that much cooler following the eruption, the yields decresed because of reduced sunlight intensity. Thus it is entirely possible that crops did not mature and yield before the onset of winter.
If anyone were to look back at contemporary records from the UK from 2011 in 100 years time they would probably come to the conclusion that it too was a year without a summer. Then someone else might look at the historic temperature record and deduce that it was actually warmer than normal.
Temperature clearly isn’t everything.
Willis: Have you looked at the link that Philip Bradley put in his comment?
http://www.islandnet.com/~see/weather/history/1816.htm
This article makes a pretty convincing case that eastern North America was hit by a series of unusually severe cold fronts in spring and summer 1816 and that it was a bad time for farmers (and has commodity price data too), but points to volcanism as just one hypothesis among several (including chance). 1816 does sound like a bad one in New England, for example:
“With an additional 175 years of meteorological records, we are able to put the Summer of 1816 into proper prospective. The mean summer temperature at New Haven of 66.2 oF was the coldest in the nearly 200 years of record and nearly 4.57 Fo colder than the mean temperature. In Philadelphia, 1816 was the second coldest year on record. The departure from normal at Cambridge, New Bedford, Williamstown and Salem, Massachusetts, and New Haven, Connecticut ranged from 2.5 to 5.0 Fo below normal for May, 5.2 to 7.0 Fo below for June, 5.4 to 7.0 Fo below during July, 1.6 to 3.2 Fo below in August, and 0.5 Fo above to 5.0 Fo below normal for September.”
Ric Werme says:
April 15, 2012 at 11:37 am
In terms of global SO4, the Tambora eruption was the second largest in the last almost 2,000 years of the Dronning Maud ice core record … so what on earth are you talking about? Because I’m talking “really big volcano” in terms of SO4 aerosols.
w.
Willis Eschenbach says:
April 15, 2012 at 1:10 pm
[On crop prices betweein 1816 and 1817.]
You’re not following the story. The prices should have been highest in 1816, due to the bad crops. They weren’t. And even in 1817, the prices were lower than in 1810.
Yeah, but if you want to bake a loaf of bread in August, 1816, you’d be using wheat from the previous harvest, which may have been okay.
By the way, 1816 was in the middle of the Dalton Minimum. Royal astronomer Sir William Hershel put forth a controversial claim that wheat prices were affected by sun spots and ultimately had to withdraw the claim.
However, other people have looked into the phenomenon and say it’s plausible, even now.
The abstract from http://xxx.lanl.gov/abs/astro-ph/0312244 (.pdf available):
Influence of Solar Activity on State of Wheat Market in Medieval England
Authors: Lev A. Pustilnik, Gregory Yom Din
(Submitted on 9 Dec 2003)
Abstract: The database of Prof. Rogers (1887), which includes wheat prices in England in the Middle Ages, was used to search for a possible influence of solar activity on the wheat market. We present a conceptual model of possible modes for sensitivity of wheat prices to weather conditions, caused by solar cycle variations, and compare expected price fluctuations with price variations recorded in medieval England.
We compared statistical properties of the intervals between wheat price bursts during years 1249-1703 with statistical properties of the intervals between minimums of solar cycles during years 1700-2000. We show that statistical properties of these two samples are similar, both for characteristics of the distributions and for histograms of the distributions. We analyze a direct link between wheat prices and solar activity in the 17th Century, for which wheat prices and solar activity data (derived from 10Be isotope) are available. We show that for all 10 time moments of the solar activity minimums the observed prices were higher than prices for the correspondent time moments of maximal solar activity (100% sign correlation, on a significance level < 0.2%). We consider these results as a direct evidence of the causal connection between wheat prices bursts and solar activity.
Willis Eschenbach says:
April 15, 2012 at 1:10 pm and at other times
Willis if you look at the paper referenced earlier there is data in Appendix 1 going from 1206 to
1914
http://www.econ.ucdavis.edu/faculty/gclark/papers/Agprice.pdf
I haven’t read the paper in detail, nor am I statician, so don’t know where their data came from or what weightings have been applied but just looking at the data published the twenty years 1801-1820 in isolation could be misleading. Looking at the published data 1816,1817 and 1818 fall in the top 60 as far as the price of Wheat, barleyand Oats are concerned. It looks like you have to see the full picture. Out of about 700 years worth of data Order by highest price first:
for Wheat
1816 20th
1817 7th
1818 10th
for Oats
1816 85th
1817 55th
1818 56th
for Barley
1816 29th
1817 7th
1818 6th
Looks like from this data 1817 may have been the year of high prices. So the price of Bread and Beer the two staples would have been high and it would not have been cheap to feed horses in England and Men in Scotland (see Dr Johnson and Boswell).
Perhaps those more qualified than I would like to investegate further.
FWIW Tambora, Krakatoa, and Pinatubo were in SE Asia, the SO2/Ash clouds would effect the NH less than the SH and Europe probably less than the US. We have data from Pinatubo on how the sun was shaded and UV was affected by the volcanos In addition to the critical points about cold snaps, crops are affected by UV.
Historically, in Europe, the two decades of wars touched off by the French Revolution ended in 1815, so looking at food prices in Europe may not be such a good proxy for temperature.
Allen MacRae:
“Claims by CAGW climate modelers of SIGNIFICANT impacts of humanmade aerosols causing sufficient global cooling to offset their claims of dangerous CO2-driven global warming must be FALSE
AND
Claims by CAGW climate modelers that Climate Sensitivity to CO2* is approximately 3.5C must be greatly exaggerated. ”
Yes, I’d say that’s about right.
Willis Eschenbach says:
April 15, 2012 at 1:50 pm
I’m so sorry, I’ve been working on taxes (e.g. what’s the basis of AFC, divested by Ford, then bought by Citigroup, who sold off the fractional shares (twice – a partial AFC share and a partial Citgroup share!) and then did a 10 for 1 stock split). I haven’t been paying much attention to Dronning Maud.
Lessee, from
ftp://ftp.ncdc.noaa.gov/pub/data/paleo/icecore/antarctica/maud/edml-so4-2004.txt :
What was that 1971 volcano? I found Villarrica in Chile, but that didn’t erupt until October, and it’s in the Southern Hemisphere anyway. Is that really 340.49 ng/g in just a week or two?
At any rate, it looks like Tambora got more SO4 out than Krakatau. That might be worth adding to my 1816 page too.
Back to taxes. Well, and everything else I was going to do. And what was the price of AFC when we got it from my mother in law’s estate? Not a problem – I have a price that’s close enough.
lgl says: April 15, 2012 at 1:06 pm
……
http://en.wikipedia.org/wiki/File:Conversation_across_the_water.jpg
Eli Rabett says:
April 15, 2012 at 2:03 pm
That probably answers my question, though it’s interesting that prices were highest after the war had finished.
Here is CET temperature record as “anomaly” from the 1781-1810 seasonal average , as provided by KNMI climate explorer, filtered with a 90 day 3-sigma low-pass gaussian:
http://i41.tinypic.com/qycwa0.png
The annotations show have years following Tambora eruption had notably milder winter than the preceding seasonal average: +1.5 and +2.0 C warmer.
This suggests that volcanoes not only cool the summer but warm the subsequent winters. This is the first time I’ve looked at Tambora but I had previously noticed this effect with the recent 20th c. volcanoes.
I also think there are indications that there is a positive warming “rebound” in the years immediately following a major eruption showing the climate feedback working to reestablish the previous state of equilibrium. “This requires further funding to investigate”.
>>Allan MacRae says:
>>I’ve been harping (since at least 2006) about the FABRICATED aerosol data that is used to fudge the climate computer models, particularly to force them to model (hindcast) the global cooling that occurred from ~1940-1975.
Alarmists claim that the rising temperatures after 1975 were the result of legislation to limit sulphate emissions. However a plot of first world and third world fossil fuel consumption shows that third world consumption exceeded first world consumption around 1980, of course with no restrictions on emissions. Claiming a drop in aerosols around 1975 sounds like nonsense.
TerryS says:
April 15, 2012 at 11:03 am
John West says:
There must have been a huge eruption in 1810, since the 1812 food prices are so high. /sarc
There was and it was called war.
The War of 1812 was between the British and the Americans.
The Peninsular War was between the British (allied with Spain and Portugal) and France.
Fighting on multiple fronts probably impacted the price of food in the UK.
===========
Also ongoing in the Napoleonic wars – 1812 Napoleon was in Borodino, the 1812 Overture and all that, and Napoleon met his Waterloo in 1915.
But, there was a huge previously unknown explosion in 1809 –
http://ucsdnews.ucsd.edu/newsrel/science/10-09Volcano.asp
“Previously Unknown Volcanic
Eruption Helped Trigger Cold Decade
October 27, 2009
By Kim McDonald and Lance Nixon
The previously unknown eruption in 1809 was larger than the Mt. Pinatubo eruption. Credit: USGS
A team of chemists from the U.S. and France has found compelling evidence of a previously undocumented large volcanic eruption that occurred exactly 200 years ago, in 1809.
The discovery, published online this week in the scientific journal Geophysical Research Letters, offers an explanation as to why the decade from 1810 to 1819 is regarded by scientists as the coldest on record for the past 500 years.
“We’ve never seen any evidence of this eruption in Greenland that corresponds to a simultaneous explosion recorded in Antarctica before in the glacial record,” said Mark Thiemens, Dean of the Division of Physical Sciences at UC San Diego and one of the co-authors of the study. “But if you look at the size of the signal we found in the ice cores, it had to be huge. It was bigger than the 1991 eruption of Mount Pinatubo in the Philippines, which killed hundreds of people and affected climate around the world.”
The wiki page on it, http://en.wikipedia.org/wiki/Year_Without_a_Summer gives a fair selection of the kind of reports I’ve read in the past about this year, and, quite frankly, I would have thought that observation would have been the first port of call to understanding that year. And from that to understanding the temperature records. And there are references..
This bit under causes interesting:
“Causes It is now generally thought that the aberrations occurred because of the 1815 (April 5–15) volcanic Mount Tambora eruption[14][15] on the island of Sumbawa, Indonesia .. The eruption had a Volcanic Explosivity Index ranking of 7, a super-colossal event that ejected immense amounts of volcanic dust into the upper atmosphere. It was the world’s largest eruption since the Hatepe eruption over 1,630 years earlier in AD 180.
That the 1815 eruption occurred during the middle of the Dalton Minimum (a period of unusually low solar activity) may also be significant.[citation needed]
Other large volcanic eruptions (with VEI at least 4) during the same time frame are:
1812, La Soufrière on Saint Vincent in the Caribbean
1812, Awu in the Sangihe Islands, Indonesia
1813, Suwanosejima in the Ryukyu Islands, Japan
1814, Mayon in the Philippines
These other eruptions had already built up a substantial amount of atmospheric dust. As is common following a massive volcanic eruption, temperatures fell worldwide because less sunlight passed through the atmosphere.”
And as P. Solar says:
April 15, 2012 at 9:02 am
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.
So in 1809 an eruption bigger than Pinatubo last century and “the decade from 1810 to 1819 is regarded by scientists as the coldest on record for the past 500 years”, and, “Our new evidence is that the volcanic sulfuric acid came down at the opposite poles at precisely the same time, and this means that the sulfate is from a single large eruption of a volcano in 1809,” Cole-Dai said. “The Tambora eruption and the undocumented 1809 eruption are together responsible for the unusually cold decade.”
Cole-Dai said the Tambora eruption was immense, sending about 100 million tons of sulfur gas into the atmosphere, but the ice core samples suggests the 1809 eruption was also very large — perhaps half the size of Tambora — and would also have cooled the earth for a few years. The researchers reason that, because the sulfuric acid is found in the ice from both polar regions, the eruption probably occurred in the tropics, as Tambora did, where wind patterns could carry volcanic material to the entire world, including both poles.”
Willis – there were famines and sickness and mass migrations from these volcanic eruptions – if you want to know why some places not as badly affected as some then as others have noted, you’ll need to take into account farming and wind patterns. That wiki page is actually a good take-off point to exploring these, because, to discount what is known historically and dismiss the devastation caused, results in your superficial understanding of the temperature record and so your:
“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 …”
is simply crass.
Re: UK food prices
By the years given and with vukcevic mentioning “Napoleon’s European experiment”, I recalled something rather important, the War of 1812, “June 18, 1812 – February 18, 1815” with the last two months being how long it took word of the peace treaty to reach the US and end the fighting.
Taken together with the Napoleonic Wars, and a blockade of American ports that “…resulted in American exports decreasing from $130 million in 1807 to $7 million in 1814” thus severely reducing shipments of American agricultural products, and likely attempts to increase British domestic production during the period that lead to a market glut later, I do not see how much can be learned by the 1816 drop in prices.
What may tell of the impact of a “Year without a Summer” is found in that study on pdf pg 103, “Appendix Table 4: Price Indices” that covers 1810 to 1849, “Arable” column, with “Arable” being field crops as detailed on pdf pg 24 in “Table 1: Weights of the arable components of the index by period.”
I would expect a lag in the price effect of a year of bad crop yields as existing stores are used up and there’s a delay before new production can supply current demand and replenish stores. Thus a bad 1816 would show up in 1817 and later prices, perhaps several years later as one year’s good production would be hard pressed to make up a bad year and fully replenish stores.
And there it is in the Price Indices, “Arable” has a strong rise for 1817-1819 before settling down to the expected range for the rest of the record to 1849. Since trade with the US had been restored which would offset production losses both domestic and with nearby European trading partners, this would indicate US production may also have had declines.
Thus it appears to me something did happen that negatively affected the production of field-grown products in 1816, affecting Great Britain, Europe, and the US as well.
For Crop Prices, one needs to look at a longer perspective than just a few years because they are highly variable, especially before 1900. Probably the biggest impact is Wars actually.
Here is a chart of Wheat Prices for 100 cities around the world (monthly) from 1800 to 1900. There is certainly an increase around 1816 but there are many other spikes (some based on local conditions such as the US South during the Civil War etc.)
http://img217.imageshack.us/img217/7751/wheatprices18001900.png
And then US Corn and Wheat Prices from 1784 to 2012 (nominal first, inflation-adjusted second). In inflation-adjusted terms, the Spring of 1817 is the highest price in the period but it is very short-lived as prices collapsed soon after. The crops of 1817 and 1818 must have been very good.
http://img33.imageshack.us/img33/7066/cornwheatprices1784.png
http://img855.imageshack.us/img855/5601/realcornwheat1784.png
Willis says: “You’re not following the story. The prices should have been highest in 1816, due to the bad crops. They weren’t. And even in 1817, the prices were lower than in 1810”
No, Willis you are not thinking. What time of year is Thanks Giving? What are thanks being given for?!
The NH harvest is early autumn for many crops. Shortages would hit the end months of the year but mainly the following year. Crop failure in 1816 would be most seem in 1817. I thought that was self evident so I did not spell it out. Apparently I was over-estimating some of my audience.
I am not totally against what you are saying. I think there is some cooling which is concordant with with volcanic events but agree that it does not jump out of the page and it is hard to pick out the years on a blind test. So there is some evidence of cooling but it’s weak and would need some stats on all such events and error margins to put it into context.
This does support the contention that climate models are being fed a highly exaggerated volcanic forcing for later half of 20th c. which is an excuse to increase CO2 to compensate.
See my previous post on warmer winters and volcano rebound. We’re not miles apart on this.
Frank says:
April 15, 2012 at 12:01 pm
Thanks for the references, Frank. Most of that depends on the Luterbacher reconstruction. This might be termed a “meta-reconstruction”, because it is a reconstruction that purports to draw together other reconstructions. At that point, what are the true error bounds? They say the reconstruction is based on instrumental series, weather diaries, letters, annals, chronicles, accounts of townships, ship cargos, agriculture, water- and windmills, the accounts of river tolls, etc …
In any case, the oddity to me is that if Luterbacher is correct, the effect of the volcano seems to be far from global, and indeed far from regional. According to your first link the cold weather seems to have hit France hard … while at the same time Poland and Russia were warmer than usual.
And when we look at Luterbacher’s full European reconstruction for the period, from your third citation above …
As you can see, the summer of 1821 on average was colder than the summer of 1816, which in turn was only slightly cooler than the summer of 1815.
w.