Fall of Rome Recorded in Trees

ScienceNOW ^ | 13 January 2011 | Andrew Curry

[neverdem]

Enlarge Image

Preserved. Climate changes recorded in tree rings correlate with important events in European history, such as the Black Death.

Credit: Wikimedia

When empires rise and fall and plagues sweep over the land, people have traditionally cursed the stars. But perhaps they should blame the weather. A new analysis of European tree-ring samples suggests that mild summers may have been the key to the rise of the Roman Empire—and that prolonged droughts, cold snaps, and other climate changes might have played a part in historical upheavals, from the barbarian invasions that brought about Rome's collapse to the Black Death that wiped out much of medieval Europe.

"Looking back on 2500 years, there are examples where climate change impacted human history," says the study's lead author, Ulf Büntgen, a paleoclimatologist at the Swiss Federal Research Institute for Forest, Snow and Landscape in Zurich. "This kind of information is not only relevant for ancient agrarian societies, it might also impact modern societies."

The study, published online today in Science, examined nearly 9000 pieces of wood, mostly collected over the past 30 years by archaeologists who use tree rings to establish the age of ancient sites or structures, a technique known as dendrochronology. With tree rings taken from living trees as a baseline, dendrochronologists work their way back in time, comparing overlapping samples to edge ever further into the past.

The researchers worked out climate information the same way. First, they compared weather records collected over the past 200 years with samples from living trees to see how temperature and moisture affected tree-ring growth. Then Büntgen and his co-authors looked at timbers from historic buildings, wood preserved in rivers or bogs, and samples from archaeological sites to push the record further back. The study used 7284 oak samples from France and Germany to see how moisture showed up in tree rings and nearly 1500 different stone pine and larch samples from high altitudes in Austria to establish a separate temperature record.

The result was a continuous—and precisely dated—record of weather in France and Germany going back 2500 years. "We were aware of these super-big data sets, and we brought them together and analyzed them in a new way to get the climate signal," Büntgen says. "If you have enough wood, the dating is secure. You just need a lot of material and a lot of rings."

When Büntgen showed the data to historians and archaeologists, they pointed out remarkable consistencies with what we know of past societies. At times of social stability and prosperity, like the rise of the Roman Empire between 300 B.C.E. and 200 C.E., Europe experienced warm, wet summers ideal for agriculture. Similar conditions accompanied the peak years of medieval Europe between 1000 C.E. and 1200 C.E.

The study also showed that climate and catastrophe often line up. In the 3rd century C.E., for example, extended droughts matched the timing of barbarian invasions and political turmoil. Around 1300 C.E., on the other hand, a cold snap combined with wetter summers coincides with widespread famines and plague that wiped out nearly half of Europe's population by 1347.

"It's a phenomenal data set with some eye-opening conclusions," says University of Arkansas, Fayetteville, geoscientist David Stahle, who was not involved with the study. "The provocative outcome is that harsh climate conditions happen to be associated with upheavals in society, like the Black Death."

By counting wood samples, the analysis also created a rough measure of human activity. In eras of prosperity, more trees were cut down for building and fuel, yielding more samples in the archaeological record. At other times, like the years after the Black Death and the so-called Migration Period between 300 C.E. and 600 C.E. when the Roman Empire was overwhelmed by tribes pushing in from the east, the number of wood samples dwindles to nearly nothing. "It's an interesting proxy of demographic trends and really the most provocative part of the study," says Stahle.

[Lucius Cornelius Sulla]

‘Funny, I would have guessed several hundred years of autocratic leadership, often by mental incompetents, bankruptcy, a declining birthrate, disease, and constant warfare...but maybe those were cool years too.’

All of these things led to civilizational collapse, but most of them went on all the time, not just during colder times. The declining birthrates and disease seems to be especially tied to colder weather.

[Captain Beyond]

GGG ping

[jsh3180]

The real story is that Europe was deeply in trouble before the weather changed for the worse in the mid 1300’s AD.
Italian bankers in Florence and Venice, primarily the Bardi and Peruzzi families had ruled over Europe for 150 years. You know, he who holds the gold, makes the rules. These banksters put the monetary screws to kings and nobility of Europe. Their greed and lending practices led to both France and England defaulting on their national debt. The bankers began having severe financial problems, so they tightened the screws on credit, put the squeeze on debtors.
As they say, some things never change, what goes around comes around.
The bankers squeezed. Feudal nobility was in debt to their eyeballs and they put the squeeze on the poor downtrodden serfs, raising tax levels to a point where the serfs could not feed their families, could not afford to borrow from “the company store” to buy seed to plant the following year. I believe it was winter 1341 or thereabouts when it got so bad, they ate what little supply of seed they had for planting the following spring.
Mass starvation and famine set in. In the space of 7 years half the population died.
Then things really went downhill, the weather changed and freezing cold and dampness set in. TSHTF.

[Tainan]

This is the wattle, The symbol of our land

You can put it in a bottle, You can hold it in Your hand.
Australia, Australia, Australia!

Right Bruce!

[SunkenCiv]

· GGG managers are SunkenCiv, StayAt HomeMother, and Ernest_at_the_Beach · · join list or digest · view topics · view or post blog · bookmark · post a topic · subscribe ·
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[steelyourfaith]

 

Beam me to Planet Gore !

[Wonder Warthog]

"The black death had nothing to do with muzzies catapulting rotting bodies over the walls of cities under siege before the escapees carried the plague back to europe. Nope. It was the climate."

Actually, there is evidence that the black plague WAS a result of the change in climate.

But you miss the real point....the data here actually says that WARMER IS BETTER, despite the last line of the abstract. So this study is actually another nail in the coffin of global warming hysteria.

[Wonder Warthog]

"Those Roman Chariots were one of the worst creators of global warming."

Man, they must have fed those horses some POTENT beans.

[Moltke]

"If you have enough wood, the dating is secure."

That statement, taken out of context, could easily be misinterpreted.

[IrishCatholic]

Thank you.
It’s a personal pet peeve of mine.
It illustrates silliness of P.C.

[Hugin]

Isn’t that what the report says.

Yes, but the article tries t draw the opposite concludion.

[neverdem]

Survey finds health-care reform bad for patients, worse for doctors

Scientists bring cancer cells back under control

Do We Really Know Earth’s Temperature?

Corrupting Psychiatry

FReepmail me if you want on or off my health and science ping list.

[muawiyah]

As has been noted before it's whatever you want it to be. If you want to say "a long time ago", that's OK. Or, you could say 5,000 years after the beginning of the great meltdown ~ a little more obscure but still gets you in the neighborhood.

NONE of the methods is Biblical.

[muawiyah]

Yes, plagues occur most readily in the aftermath of a cool period with plenty of rain followed by a cool dry period where grass thrives. When grass does well so do the nut trees, and when they do well, the rodent population skyrockets.

And so on. Whether it's the fleas and other vermin on the rodents or the rodents themselves, that's the way you get it.

Rotting corpses of humans usually aren't all that good a vector anyway.

Now, a point about the Islamics spreading plague, they forgot to spread the earlier and even worse one called The Plague of Justinian.

That's because there was no Islam at that time.

You can argue that plague gave rise to Islam as a major military and cultural power ~ mostly by killing off everybody but the desert Arabs.

[Fiji Hill]

“BC” and “AD” have been used for two millennia. “BCE” and “CE” are of recent origin and clearly Christophobic. I first encountered “BCE” and “CE” in a book published in Communist East Germany.

[neverdem]

You can argue that plague gave rise to Islam as a major military and cultural power ~ mostly by killing off everybody but the desert Arabs.

LOL! Not a bad correlation, but I wouldn't restrict it to just desert Arabs.

With my winter eczema, I'll take warming.

[GOPJ]

Thanks for the ping.

[Walkingfeather]

LOL

[GOPJ]

More climate hysteria disguised as policy-neutral scientific inquiry.

My first impression too.