Greenland and AGW

The last written records of the Norse Greenlan...

The last written records of the Norse Greenlanders are from a 1408 marriage in the church of Hvalsey...Image via Wikipedia

Guest post by S Jay Porter

In 891 AD. Eric The Red set off from Iceland with a few followers to explore a land to the west which they had probably spotted some time before while sailing out in their longboats, and then returned three years later with about 500 fellow Vikings. At first they settled on the south-east coast, close to the tip of this new land and then, as the population grew, created a further settlement to the south-west. They called their new home ‘Greenland’.

It has been said that this name was a ‘spin’, a publicity stunt to entice more Vikings to come to join the new settlers, but this would have been pointless if it had been impossible for them to survive. They must at least have been able to create their own dwellings, build their own fires, make their own clothes and above all, grow their own food. The settlers might have been able to trade such things as polar bear-skins and fox furs for iron and other necessities on occasional trips to Europe, but their compatriots in Denmark and Iceland would have been neither able nor willing to row their longboats out each month with groceries.

At present, the temperatures in Greenland range from a maximum of 7C in July to -9C in January. This is too cold for grain such as wheat and even rye to grow and ripen in the short summer of such northern latitudes. Nor are sheep and cattle happy at those temperatures. Hill sheep might be able to nibble away at moss and short grass, but cattle need lush meadows and hay to fatten and live through a winter. Solid wood is needed for building, boat building and warmth, but only bushes and such weak trees as birch now grow in Greenland.

In 1991, two caribou hunters stumbled over a log on a snowy Greenland riverbank, an unusual event because Greenland is now above the treeline. (1) Over the past century, further archaeological investigations found frozen sheep droppings, a cow barn, bones from pigs, sheep and goats and remains of rye, barley and wheat all of which indicate that the Vikings had large farmsteads with ample pastures. The Greenlanders obviously prospered, because from the number of farms in both settlements, whose 400 or so stone ruins still dot the landscape, archaeologists guess that the population may have risen to a peak of about five thousand. They also built a cathedral and churches with graves which means that the soil must have been soft enough to dig, but these graves are now well below the permafrost (2).

There is also a story in ‘Landnamabok, the Icelandic Book of Settlement, which tells of a man who swam across his local fjord to fetch a sheep for a feast in honour of his cousin, the founder of Greenland, Erick the Red. Studies of Channel swimmers show that 10C would be the lowest temperature that a man would be able to endure for such a swim, but the average August temperature of water in the fjords along the southern Greenland coast now rarely exceeds 6C. The water at that time must therefore have been at least 4C warmer and probably more than that which means that the summer temperatures (for the air) in the fjords in southern Greenland would then have been 13C-14C, (3) as compared with the present temperatures mentioned above.

It follows that temperatures must have been higher than those of today’s during that first settlement of Greenland which lasted from approximately 900 until the mid-1400s AD, when these settlements died out. There is no written explanation for this sudden demise but climate scientists have discovered that Iceland, like the rest of Europe, was gripped by a rapid and centuries-long drop in temperature, known as the Little Ice Age. And in a recent study, William D’Andrea and Yongsong Huang of Brown University, Providence RI (4) have traced the variability of the Greenland climate over a period of 5,600 years when previous inhabitants were also subjected to rapid warm and cold swings in temperatures

Yet the whole reason for the existence of the Intergovernmental Panel of Climate Change (IPCC) is to thrust upon the world’s population the idea that industrialisation in the West over the last 100 years and our profligate use of fossil fuels is producing a run-away heating of the planet through the emission of greenhouse gases, mainly CO2, which unless checked will lead to its — and humanity’s — death. The western governments are happily looking forward to a vast increase in taxes to pay for measures to reduce ’carbon emissions’ and even the possibility of a Global Government to control everything has been mentioned (5).

So the possibility that temperatures were higher in the past in any part of the world was a thorn in the sides of those Climatologists who are wedded to the whole idea of Anthopogenic Global Warming (AGW), also known as Climate Change.

Unfortunately for them, an English Climatologist, Hubert H Lamb, first formulated the idea of a Medieval Warming Period (MWP) in 1965 and other surveys have found that this warming did not just occur in the northwestern hemisphere but was global (6). Lamb founded the UK Climate Research Unit (CRU) in 1971 and until the mid 1990s the MWP was undisputed fact and was shown even in the IPPC progress report of 1990. But Dr David Darning (University of Oklahoma College of Earth and Energy) in his recent testimony to Congress (7) said ‘…I received an astonishing email from a major researcher in the area of climate change. It said “We have to get rid of the Medieval Warm Period”’ And this the ‘warmist’ Climatologists certainly tried to do.

In 1998 a graph was produced by geophysicist Michael Mann, known as the Hockey Stick Graph’, which managed to almost air-brush out of existence the Medieval Warming Period . This was published in the eminent scientific magazine Nature and also in several places in the IPPC Report of 2001 and created a world-wide sensation. Here was proof positive the world was overheating and it was All Our Fault.

However, investigation of the graph by historians and climatologists who doubted the existence of global warming, brought criticism centred around the statistical method used and the associated computer programme. It was eventually called the most discredited study in the history of science and quietly dropped by the IPPC from the latest 2007 IPPC report for policy makers.

The Hockey Stick graph had also attempted to remove the Little Ice Age which was another world-wide event, lasting from roughly the early 14th century to the mid-19th century with short interspersed warm periods. It is well-known from written reports that temperatures must at times have been considerably lower than in the Medieval Warming Period since Frost Fairs were often held on the frozen Thames until 1814 and in 1658, during the coldest period of the Little Ice Age, King Karl X Gustav of Sweden led an army across the frozen Danish waters to lay siege to Copenhagen.

It was also at this time that the Viking settlements in Greenland gradually died out. The Medieval Warming Period is usually agreed to have lasted from approximately 900 to approximately 1300 AD and from then onwards the climate cooled again. Glaciers grew, sea ice advanced and marine life migrated southwards as it did so, leaving the Greenlanders with a smaller and more difficult catch. The summers became shorter and progressively cooler, limiting the time cattle could be kept outdoors and increasing the need for winter fodder which became less available. Trade between Greenland, Iceland and Europe became more difficult and finally ceased. (3) It can only be hoped that a few Greenlanders escaped to re-settled somewhere less cold before starvation overcame them all.

But since temperatures during the Medieval Warming Period were higher in Greenland than they are even today, and since this was followed by a Cooling Period, and since this has happened many times before (which have not been considered here), the fact that the earth may have warmed somewhat since the mid 1850s is not unusual. Nor will it be unusual if the temperatures now start to drop.

Above all, since man was not industrialised before the mid-1850s and so was not emitting any huge amounts of CO2, any warming which has occurred over the past 150 years (for which we should be grateful) is obviously a natural event and —

— NOT ALL OUR FAULT!

——————————————————————————————————————————–

Word Count: 1,418

Sonya Porter

Source Material:

(1) http://watsupwiththat.com (The Viking farm under the sand in Greenland by Terese Brasen)

(2) http://www.archaeology.org

(3) ‘Heaven and Earth’ by Prof. Ian Plimer

(4) http://wattsupwiththat.com/2011/05/31/temperature-reconstruction-of-greenland-shows-ups-and-downs-in-climate-happened-over-5600-years/

(5) http://www.youtube.com/watch?v=0lsltxgrr_o

(6) http://www.science-skeptical.de/blog

(7) http://epw.senate.gov/hearing_statements.cfm?id=266543

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Joseph

Thanks for the post, it was very good.
A question for you however; does the peer reviewed journals of today admit that there was a “little ice age” or do they call it a “local event”?

Brian H

The Warmistas are jealous, and want to cause even more mortality than the Black Death and LIA.

how about the Faer-Oer and Svalbards? What are the written records about them saying?

Geoff Sherrington

If the globe has been warming since the Little Ice Age, what mechanism do you favour? Where is the “warmth” being stored? It is logical to postulate that the ocean mass is warming, but do we have evidence for this? It would also be logical that more heat from the sun was now reaching the Earth than in the LIA. Do you agree?

golf charley

Excellent summary and explanation of why Michael Mann, his Hockey Stick and the Hockey Team require the same treatment that they dealt to the Medieval Warm Period

Thanks Mrs Porter, great post!
There is one small correction I would like to suggest. The link (6) should lead directly to the MWP map. Here is the link:
http://pages.science-skeptical.de/MWP/MedievalWarmPeriod1024x768.html

gyptis444

Over 200 papers mention the MWP and they are summarised in ‘Climate Change Reconsidered’ by the Non-intergovernmental Panel on Climate Change (NIPCC). The analysis therein shows the geographical spread of the studies, the frequency distribution of the estimates of peak temperature, and demonstrates that the vast majority of studies revealed temperatures at least as warm as the present. And yet, the IPCC and their AGW believers have done their best to ignore this. The IPCC’s discussion of the MWP was, at best perfunctory and certainly inaccurate not to say misleading.

DougD

“But Dr David Darning (University of Oklahoma College of Earth and Energy) in his recent testimony to Congress…”
The professor’s name is Deming, not Darning.
Doug

John Marshall

The MWP is real and climates change. Alarmists should get used to it.

Ed Zuiderwijk

Remember the fabled North-West passage? There also was a mythical North-East passage which was of great interest to the Dutch East India (VOC) company in the late 16-th century. Not only would a route to the Far East be shorter than around the Cape, but also it would keep the VOC ships safe from the Portuguese and Spanish navies.
So, they organised an expedition to find that NEP and two ships (“Houtman” and “de Keyzer”) under command of a guy named Willem Barentsz (yes, that sea is named after him). In fact there were two expeditions and the second one (in 1596) went disasterous: the ships got stuck in the ice and the crews had to survive two harsh winters on the shores of Nova Zemlya; they succeeded to return after two years in the wilderness and with great losses. Result of the exploits: there is no NEP. In 1600 it
was completely frozen over.
But why did they think there was this NEP in the first place? Well there were stories from the Nordic countries of people sailing North of Russia all the way to the East. Those stories were at least several hundred years old in 1600. Hence, in the MWP the NE passage was passable, then with the climate cooling it became inpassable again. Now it is passable again. In fact the first ship using it in modern times was in about 1935 and that ship did it without help of an icebreaker.
Knowing this story, as every Dutch schoolboy from the 1960-ies did, I knew the moment I saw the “hockey stick”, that it was a fraud.

OldSchoolboy

In elementary school I was taught that the Vikings intentionally misnamed Greenland and Iceland (Greenland was in fact an “ice land” while Iceland was actually green) to confound enemies seeking to raid their colony. I have no idea who made this up.

MarkW

I’ve been wondering. The super nova that caused the Crab Nebula was spotted by the Chinese in 1054, it was bright enough to be seen during the day for a short time. The Crab Nebula is 6500 light years away. Gamma rays traveling at 99% of the speed of light would have arrived 65 years later. Those traveling at 90% of the speed of light would have arrived 650 years later. So gamma rays from this nearby super nova would have been arriving during the period of the little ice age. Coincidence?

MarkW

I’ve had “discussions” with Warmistas who still claim that the Hockey Stick has been proven and that it is the definitive scientific statement.

P. Solar

An excellent , well written piece.
A few of the refs need checking though.
ref 1 to this site has a typo and does not point to anything relevant that is a source for what is written.
I don’t see anything on ref 2 about Greenland churches etc. ; same prob as above.
youtube has pulled the vid in ref 6
ref 7 gets me a 404.
I initially though “wow, a good list of references too”, until I tried them 🙁
Easily fixed I would have thought. Otherwise a landmark in quality here at WUWT, raising the bar for others to follow.
Many thanks.

golf charley

Ed Zuiderwijk
The determination with which the British and others sought the North West Passage has always led me to believe that they knew it was there, a bit like Columbus “discovering” america, he had a map.
Good to hear a similar perspective about the NE Passage

KnR

The important word is ‘unprecedented ‘ , that is the political need to make current climate events as dramatic as possible to the public in order to obtain political goals that otherwise the public would reject. . Its seen all the time in AGW supporters, the doom is always worse, the sea will always get higher, the earth is going to get even hotter.
So the need for ‘unprecedented ‘ lead to the need to get rid of events that made this idea logically impossible, hence the death of MWP which the Hockey Stick was designed to bring about . It is a poor piece of research , in the normal process of science it would have been challenged and people would have lost interest. But the Hockey Stick is not just a piece of research anymore, its taken on a life of its own it has in effect become an icon of ‘faith’ From those like Mann how careers are very much tied into it , for without this what does Mann have , it’s also their seat on the eco-gravy train and the top table of ‘important’ people . So they will defend it to the death, science has nothing to do with it .

James Schrumpf

@MarkW:
Not sure where you get the .90c and .99c figures for gamma rays, but they are electromagnetic radiation, and as such travel at the speed of light the same as visible light. The gamma rays would have arrived in 1054 as well.

amicus curiae

There are traces from old Glaciers in Sth australia, I remember being taken to see them as a schoolkid, so we sure had some Ice around down here also.
and the Murray rivers mouth was NOT always where it is now, but we have “scientists” telling us man is killing the Murray and forever changing the environment etc etc.
hmm
seems mother nature manages to move the furniture round rather well without our input:-)
and thanks for the leads to look at old settlements etc.

Mariwarcwm

Of course it is not our fault. But you can find as much evidence as you like to disprove CAGW: no one but us skeptics howling out here in the wilderness is listening because there are too many snouts in the trough for taxpayer funded subsidies and jobs.
Is there a newly retired economist out there looking for a hobby? Why not tot up all the CAGW funded posts and subsidies and report on the cost and size of this gravy train. I would be very interested to know. I would set about doing it myself but maths is not my strong subject, and I guess that the figures would be very large.

Confused...

MarkW says:
June 1, 2011 at 4:23 am

Um, gamma rays have to travel at the speed of light, c, given that they are a form of electromagnetic radiation, namely very high energy photons… How do you get them to travel at 0.9 or 0.99 c through space?

An Engineer

Ref GS’s comment at 0359, whilst these are good and interesting questions, the article is proposing that the current climate variations are no different to those observed in the past.
It is not required that people have to prove how the climate works in order to disprove the proposal that CO2 is causing the variation. If somebody is proposing that CO2 is causing the recent fluctuations, the onus is on them to demonstrate how this works, with the theory substantiated by direct observations.

Adam Gallon

MarkW says:
June 1, 2011 at 4:23 am
Twaddle!
Gamma rays are but very short wavelength electromagnetic radiation, so travel at exactly the same speed that light does. Astronomers find detecting Gamma rays easier than a faint light source, thus they often detect a Gamma Ray Burst, then try to image the object in the visual spectrum.
http://en.wikipedia.org/wiki/Gamma-ray_burst

Daniel H

In general, it’s a good article but, unfortunately, there are way too many typos, factual errors, and dubious claims littered throughout the text for it to be taken seriously. For starters, it’s not called the “Medieval Warming Period” but the “Medieval Warm Period“. Next, in paragraph 11, you claim that there was an “investigation of the graph by historians and climatologists who doubted the existence of global warming“. Actually, very few skeptical scientists dispute that recent global warming has occurred. They disagree with the claim that the warming is unprecedented and/or that it was mainly caused by humans. You then go on to say about the Hockey Stick that “It was eventually called the most discredited study in the history of science“. According to whom? I mean it’s an incredible claim to make and yet there are zero citations provided. That seems unwise given Dr. Mann’s propensity to sue his detractors for libel over seemingly innocuous remarks.

pytlozvejk

Anthony
Simple facts, but brilliant. The problem is that facts don’t convince ideologues and power-hungry weirdos. Did Lysenko ever retreat in the face of facts?
BTW, you need to get a proof-reader. Someone else has mentioned Deming/Darning. There’s also a para where you mention “Hock Stick Graph”. Just sayin’ …

@MarkW
6500 lightyears is too far away, and gamma rays travel at lightspeed (its cosmic radiation that is slower). In order to be able to do something to our atmosphere the star has to explode between a 100 to 3000 years from Earth depending on the stars mass during the core-collapse.
Gamma rays from a supernova would induce a chemical reaction in the upper atmosphere converting molecular nitrogen into nitrogen oxides, depleting the ozone layer enough to expose the surface to harmful solar and cosmic radiation.
A most likely candidate to blow sky high is HR 8210 at 150 light years which then explodes in a Type Ia supernova, but that could still be a few million years away and estimates say that to really do damage to the Ozone layer requires a supernova at around 25-35 lightyears away.
For the moment being a supernova is way down on the list of things that would mean the end of us 🙂

Pull My Finger

The gamma rays would arrive in 6500 (1054 ad) years, not 65. The actual super nova would have been in the 6th Century BC, which happens to coincide with a lot of serious progress for humans, the Biblical flood, and some massive climate changes.
Coincidence? I THINK NOT! 🙂
———————–
The Crab Nebula is 6500 light years away

Pamela Gray

Those that postulate current CO2 causation (as opposed to historical natural drivers) fail miserably regarding the energy required to warm up Greenland. The only place that energy could have come from at that time in history would be within the confines of a weather pattern variation (think stationary pressure systems that parked themselves over Greenland, or major influx of warm ocean currents along the coastline). Weather pattern and oceanic systems have tremendous energy in them. Way more than the ever so slight rise in CO2 in terms of ppm – IE not relative to itself but relative to the total parts of the atmosphere.

UK Marcus

Sonya, thanks for posting this illuminating story.
The great Chinese fleets, are reported to have sailed around the north coast of Greenland, c.1420.
They then ignored most of Europe as being, presumably, too backward and with nothing to contribute to their understanding of the world they had just discovered – America and Africa.

With the vested interests of Greenpeace, Fiends of the Earth and all the other “Green” organisations investing huge amounts of time and effort into impoverishing the West and destroying any sensible economic development, this sort of information will always get hidden, discredited and buried if they can.
This is no longer a debate about science or even a scientific search for truth, this is about whose ideology ultimately succeeds – and Greenpeace et al are front organisations for Fabians and anarchists.

Mike(One of the Many)

“MarkW says:
June 1, 2011 at 4:23 am
I’ve been wondering. The super nova that caused the Crab Nebula was spotted by the Chinese in 1054, it was bright enough to be seen during the day for a short time. The Crab Nebula is 6500 light years away. Gamma rays traveling at 99% of the speed of light would have arrived 65 years later. Those traveling at 90% of the speed of light would have arrived 650 years later. So gamma rays from this nearby super nova would have been arriving during the period of the little ice age. Coincidence?

Surely, you mean cosmic rays i.e. highly energetic charged particles accelerated by ultra powerful magnetic fields?
Gamma rays, are electromagnetic and they will travel at the speed of light in the medium in question, in this case a vacuum, so that would be c, not a fraction of c. Though, a close gamma ray burst, hitting us dead on would not be good for us or the rest of the planet and large quantities of galactic cosmic rays might have an effect on cloud cover, Svensmark et al
So, you’re not entirely wrong

Pull My Finger

There is no question MWP and LIA existed, the effects of them have been taught in introductory history classes for decades. The Biblical Flood is spoke of in practically every civilizations history, one theory is a massive glacial melt flood at the end of an ice age in 9th millenium BC. We know the dark ages were cold and damp and miserable. One theory as to why such crazyness happened, especially with the witch hunts, was due to a fungus that grew on wheat during cold damp seasons which had some of the properties of a halluciagen.
Science shows that climate changes over geologically short time periods, history is full of such stories and cultural evidence, so what does that make the Climate “Scientists”? They deny science, they deny history, so I think they are the denialists.
If they want to live in the 14th Century they are free to try, just don’t drag me with you.

Keith G

Ms. Porter,
Excellent post! There is an obvious corollary to your summary. Phase I of the supposed disastrous rise in sea levels is largely based on melting of the ice sheets on Greenland. If Greenland was significantly warmer in historical times, and sea levels did not rise noticeably then, why would they now when temperatures are still below what they were?
Graves dug in soft soil that is now permafrost? Forests in an area that is now above the tree line? Historical evidence of cattle and sheep when modern breeds and improved shelters aren’t enough to allow significant animal husbandry? Wheat fields in Greenland?
It’s simply mind-boggling that the storyline of coming floods still has legs given the historical evidence.

Fred from Canuckistan

Have they figured out yet how many Hummers Eric the Red owned?
What colors were they?

Jon

“Studies of Channel swimmers show that 10C would be the lowest temperature that a man would be able to endure for such a swim, but the average August temperature of water in the fjords along the southern Greenland coast now rarely exceeds 6C. The water at that time must therefore have been at least 4C warmer ”
A bold statement … does this take into account their physiological adaptation to cold?
http://arctic.synergiesprairies.ca/arctic/index.php/arctic/article/view/1530/1509

Icarus

The climate history of Greenland is interesting but it doesn’t have much relevance to the global warming we’re seeing today. No ‘skeptical’ climate scientist is going to claim to have refuted AGW just because it was equally warm or warmer at some time in the past, either regionally or globally.

MikeH

For notation (7), the link is wrong, there is a . after the word hearing, it should not be there..
Here is the correct link:
http://www.epw.senate.gov/hearing_statements.cfm?id=266543
Also, notation (5), the youtube account has been suspended due to copyright issues (oops). Is there another link to the same information?

Dave Springer

re; gamma rays from Crab Nebula supernova
Cut MarkW some slack. He meant to say cosmic rays, not gamma rays. Cosmic “ray” is a misnomer as they are actually charged particles moving at a significant fraction of light speed. Cosmic rays are indeed thrown off by supernova.
6500 light years is NOT too far away to effect our atmosphere. It was visible in the daytime sky. How many astronomical objects can be seen in the daytime sky? If it’s bright enough to be seen in the daytime sky from the ground think of how bright it must have been nearer to the top of the atmosphere.

ZZZ

The comments about gamma rays traveling exactly at the speed of light are correct, but cosmic rays (high-speed protons, heavier atomic nuclei, etc.) generated by the supernova would travel at slower velocities. Since these particles are charged, they can be deflected by galactic magnetic fields before reaching the solar system, making it more difficult to estimate when they would get here.

Dear Mr Porter:
May I translate this post into Spanish and publish it in my blog, “El Atril del Orador”, with due credits and links, of course?

Don B

In this study by the University of Alberta of a Norse farm site, Garden Under Sandet, they reported the site was well preserved because “the site was sealed by alluvium and permafrost.” The say that during the climate optimum period of the MWP between AD 800-1200, temperatures were 1-4 C warmer than today.
large file, 205 page report:
http://www.collectionscanada.gc.ca/obj/s4/f2/dsk2/ftp04/mq22551.pdf

BBk

Not sure where you get the .90c and .99c figures for gamma rays, but they are electromagnetic radiation, and as such travel at the speed of light the same as visible light. The gamma rays would have arrived in 1054 as well.

I was going to say the same. Still, gamma rays aren’t the only things ejected from a supernova. It’s concievable that super-nova accellerated particles could have arrived in the time period described. Whether that would have an impact on climate is a seperate question. Certainly something to look at and see if any correlations can be drawn.

Laurie Bowen

Well, this is odd . . . I googled “I received an astonishing email from a major researcher in the area of climate change. It said “We have to get rid of the Medieval Warm Period”’ And this the ‘warmist’ Climatologists certainly tried to do.”
and it went to http://epw.senate.gov/hearing_statements.cfm?id=266543
and that is S Jay Porter’s same link . . . U.S. Senate Committee on Environment & Public Works, Hearing Statements, Date: 12/06/2006 without the _ .
I think it always has to be stressed that . . . . many things in life are
“obviously a natural event and –
– NOT ALL OUR FAULT!” . . . . Kinda’ like Death??. . . .

Dave Springer

@Robert (whoever that is)
Nobody talked about the Crab supernova “spelling an end to us”. The implication is to Svensmark’s hypothesis (which appears to have been experimentally confirmed which makes it a theory now) that waxing and waning of cosmic ray flux causes more or less formation of high altitude clouds which in turn cause more or less visible light from the sun to be reflected which in turns means more or less energy arriving at the surface to warm the ocean.
There are two things which determine the cosmic ray flux reaching the earth’s atmosphere. The first is the density of the flux reaching our solar system which varies in both predictable and unpredictable ways. A predictable way is where in the galaxy the solar system happens to be. Our solar system, over periods of many millions of years, wanders above and below the galactic plane. It also orbits the center of the galaxy at a different speed than the spiral arms so it also periodically passes through one of those arms. As stellar density increases so does the average cosmic ray flux as there are statistically more violent events that generate the rays in areas of greater stellar density. The second thing that determines cosmic ray flux reaching the earth’s atmosphere is the strength of the solar magnetic field. Sunspot number is a reasonable proxy for solar magnetic strength and people have been keeping a decent record of sunspot number for 400 years and there is a marked correlation that has been known for quite a while between sunspot count and climate.
So there.

MarkW

I meant cosmic rays, sorry.

Paul Nottingham

I think it would also be useful to look at the Great Frost of Ireland in the 1740s where conditions were so severe that proportionately as many people died as in the Great Famine of the 1840s. This event seems to be generally forgotten nowadays but presumably this is the environment to which warmists wish us to return.
http://en.wikipedia.org/wiki/Irish_Famine_%281740%E2%80%931741%29

pytlozvejk says:
June 1, 2011 at 5:04 am
Anthony
Simple facts, but brilliant. The problem is that facts don’t convince ideologues and power-hungry weirdos. Did Lysenko ever retreat in the face of facts?
BTW, you need to get a proof-reader. Someone else has mentioned Deming/Darning. There’s also a para where you mention “Hock Stick Graph”. Just sayin’ …

Not to mention several references to the “IPPC”…otherwise an excellent summary, but proofing would have made it even more so.

Craig Loehle

I have seen many blog comments in various places insisting that Greenland was not warmer in the MWP than today. Just handwaving away the evidence about trees growing then and cattle and graveyards frozen solid. Besides as a greeting, I just hate handwaving…

Robert of Ottawa

It was the historical evidence that made me skeptical. Why I say there is a lack of proof or evidence that the current warming is caused by man is because it cannot be shown that the current warming is anything unusual as this has happened before.

Steve Keohane

Excellent piece Mr. Porter. Human experience trumps statistical fantasy every time. It was warmer during the MWP than now. For those who want global references to the same, see: http://www.co2science.org/data/mwp/mwpp.php
OldSchoolboy says: June 1, 2011 at 4:22 am
In elementary school I was taught that the Vikings intentionally misnamed Greenland and Iceland (Greenland was in fact an “ice land” while Iceland was actually green) to confound enemies seeking to raid their colony. I have no idea who made this up.

I was taught a different variation, probably wrong, that they confused the naming of Iceland and Greenland, the warmer place Iceland, was supposed to be called Greenland. This would have been in the late 1950s.

Dave Springer

re; cosmic ray flux
I forget to mention the unpredictable way in which cosmic ray flux varies. Orbital mechanics of the solar system about the center of the galaxy is predictable. What isn’t predictable is relatively nearby supernovae events. More or less stellar density makes these nearby events statistically more or less likely but on an event by event basis it’s still unpredictable.
I also didn’t mention the mechanism by which variable solar magnetic field effects cosmic ray flux. Cosmic rays are charged particles and thus can be deflected magnetically. When the solar magnetic is strong more cosmic rays are deflected away from the earth and when weaker fewer are deflected.
Solar magnetic field strength is somewhat predictable but we don’t really have a long enough record for statistical prediction nor a good enough understanding of solar physics for theoretical prediction. The ~11 year sunspot cycle is statistically predictable but the peak strength and weakness is less so. There appear to be centuries long cycles in that. The so called “Maunder Minimum” where sunspot counts were anomalously low coincided with the “Little Ice Age”. In the past 50 years there has been a yet to be named solar maximum. I’ll be dollars against donuts that the history books in future will have a name for the present solar maximum. It’s only just now being recognized that it was a maximum mostly due to the fact that appears to have ended with the most recent sunspot cycle. We are witnessing history being made.