And your point is?

This is one of those articles where you ask, why given the writers obvious predetermined conclusions, did he write it? Before I get into the actual article I thought the picture that is with the article (below) a bit strange. Actually the picture is fine it is the description that was posted with the picture that seems a bit unusual. The article is from I, Science, the Science magazine of Imperial College

Tree rings, like these, are rings made of tree

Climate change – history’s invisible foe
When it’s cold, do you get grumpy? Ill? Hungry? A sudden urge to emigrate? Well, according to a study published in this week’s Science journal, that’s nothing new: changes in climate have been causing Europeans to migrate, starve, die of horrible diseases and invade our neighbours – the ultimate expression of grumpiness – since the Iron Age. 

Scientists from universities in Switzerland, Germany and Austria analysed tree rings in wood dating back 2500 years. Their results provide the first glimpse of what the weather was like for our distant ancestors on a yearly basis and show that changes in temperature coincided some of the most disrupted years of human history.

Now I know what you are thinking, here is an article blaming global warming for past calamities. Well you would be wrong.

European trees create new rings once a year – there’s a period of woody growth during the spring and summer which stops when the tree loses its leaves. The rings vary in width according to temperature: when the summer is warmer, the tree grows more and its ring that year is wider
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The paper’s authors studied oak samples taken from wells and wetlands across Europe and, while they weren’t able to measure exact temperatures, by looking at the relative ring widths they could find out when temperature was rising and falling. It’s been suggested that temperature changes impact on societies; affecting water supply, food production and human health – an idea that’s strongly supported by the paper’s results. 

The first major dip in tree ring width, at around 350BC, lasted for around 100 years and coincides perfectly with the Celtic expansion, when the Celts spread out from what is now Austria to populate lands as far away as Scotland, Bulgaria and Southern Spain. The second big drop occurred at around 50BC, just as Julius Caesar was busy invading Britain.

I will not get into the science of tree ring proxies, simply because I have only a poor layman's knowledge of the subject, but do make note of the writer's asertion which I believe to be true, "while they weren’t able to measure exact temperatures, by looking at the relative ring widths they could find out when temperature was rising and falling."

The most sustained cooling started in the 3rd century AD and lasted for 300 years – a time when the Barbarian Invasions were causing serious headaches for the Western Roman Empire and hundreds of thousands of people were on the move in what’s known as the Migration Period. 

Famine struck Europe between 1315 and 1317 when crops failed for three successive summers. Millions of people starved to death or succumbed to disease and stricken survivors resorted to infanticide and cannibalism. The period has been described as the ‘Little Ice Age’ and the tree rings show a sharp temperature drop. 

This unfavourable climate continued until the mid 14th century and may have been instrumental in weakening the overall health of Europeans, leaving them vulnerable to the worst plague in history – the Black Death. More recent drops correlate with the 30 Years’ War and the Modern Migration.

By now, you may be thinking that cold equals bad and warm equals good, so why should we be worried about global warming?

No, actually I was not thinking that, because any student of history knows "cold equals bad and warm equals good" which is also the main reason I settled in Florida. What I really am asking myself is why, with all the evidence to that fact, do nincompoops vilify a warmer climate. But this being the age of unreason, even while writing articles about the perils of a colder climate the author needs to warn us of the perils that await us:

The events described here coincide with relatively small fluctuations. In the data from the tree rings, there is not a single point between 500 BC and 1900 where temperatures deviate away from the average by more than two degrees. However, the late 20th data show temperatures rising to 3 degrees above average. 

Europeans have never seen heat like this. We could be in for a bumpy ride.

A couple of final observations here. Note  that the article does not document the events that coincide with periods of warmth, had they done so the contrast might have been too much for the author to deny.

The other point is this comment " In the data from the tree rings, there is not a single point between 500 BC and 1900 where temperatures deviate away from the average by more than two degrees. However, the late 20th data show temperatures rising to 3 degrees above average."  How is it possible to determine data with such precision when in the very beginning we were told "they weren’t able to measure exact temperatures." 


Shazam! In the short distance of a one page article science has suddenly gone from being unable to determine exact temperatures from tree rings to being able to determine that the data shows the late 20th century was 3 degrees above average, Well how do you determine an average when you can not determine temperatures from tree rings?

I guess the question remains, why on Earth did they write this article,,,,,Oh I know, so that despite evidence to the contrary, evidence in their very own article they just wanted to warn the world "We could be in for a bumpy ride." Which based upon their article is only true if the climate is cooling, which is probably true.