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Posted on 09/23/2010 6:01:49 PM PDT by SunkenCiv
A sudden and sharp rise in the 14C-content of the atmosphere, which occurred between ca 850 and 760 calendar years BC (ca 2750-2450 BP on the radiocarbon time scale), was contemporaneous with an abrupt climate change.
In NW-Europe (as indicated by palaeoecological and geological evidence) climate changed from relatively warm and continental to oceanic (cooler and wetter).
Archaeological and palaeoecological evidence for the abandonment of low-lying areas at the Bronze Age/Iron Age transition in The Netherlands is interpreted as the effect of a rise of the water table and the extension of fens and bogs.
...
The discussed oscillation of 14C at ca 2650 BP was probably caused by a reduced solar activity which could also have been the forcing mechanism behind the recorded cool event.
An important effect of a reduced solar activity is an increase in the cosmic-ray flux leading to a higher production of 14C in the stratosphere and an increased cloudiness and precipitation.
The reduction in solar (ultraviolet) radiation may also have lead to a decline in ozone production in the lower stratosphere and the latter process may have been the trigger mechanism responsible for the inferred climate changes, because a decrease in the stratospheric ozone content produced cooling of the lower stratosphere by the absorption of less sunlight.
This could have resulted in a decrease of the latitudinal extension of the Hadley Cell circulation and a possible associated weakening of monsoons, which would be consistent with inferred drier conditions in the tropics.
Furthermore an expansion of the Polar Cells and a repositioning of the main depression tracks at mid-latitudes towards the equator may have occurred.
This probably has resulted in the reconstructed change to cooler and wetter conditions at middle latitudes in both hemispheres around 2650 BP.
(Excerpt) Read more at knowledge.co.uk ...
The Impact of Abrupt Climate Change around 2650 BP in NW-Europe, Evidence for Climatic Teleconnections, and a Tentative Explanation
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Obviously caused by the Assyrians and their 2 SUV's in every home policy.
Gee, that type of incandescent light bulbs and v8 cars did they have back then that caused that climate change? And how could it happen in that area when all the bad folks who consume so conspicuously are Americans?!?!? Andf how could they get such a radical change without Styrofoam Bug Max boxes?
And I found it searching on 2650 BP.
Because I was trying to figure out a correlation between that date and the date on the Graphic that SH posted...
Can someone tell what is 2650 BP.
I suppose I should know....hmmm.
and between 1350 and 1750...mini ice age
lack of sunspots
see
http://sohowww.nascom.nasa.gov/sunspots/
for todays two sunspots.
It was Bush’s fault.
A cooling period in Europe would definitely have spurred the subordinate tributary tribes along the Danube to boot out the warrior elite groups ~ at just this period of time.
Galician records report that the Celts arrived in Northern Spain in this period, and moved on to Brittain about 100 years later (as things warmed up presumably).
It's all making sense now.
Thanks....gonna have to munch on all of that for awhile....
The pulse of the climate (cold to warm to cold to warm etc) seems to have been the large reason for the migration down the steppe, probably in both directions.
BP = Before Present. :’) In radiocarbon dating, that would be Before 1950. :’)
Thanks, I think I’ll steal that map. :’)
Thanks, E did something similar as well.
http://www.freerepublic.com/focus/chat/2595206/posts?page=8#8
Now they were a pretty organized and aggressive society at the time (kept up with the Chinese in technology) so from their base in Bhutan they moved out into india proper well enough that they show up as one of the fighting factions in the Mahabarat.
They maintained contact with Yakutia (currently the largest subdivision of Russia in Siberia) with trade routes all over the place ~ and a big connection into what we today call The Silk Road.
When the climate got cold they moved much of their nation South to India. When it warmed up, or the Indians got restive (see 200AD) they moved the nation North.
About 560 AD they MOVED EAST to Korea, and then Japan. I gather that climate anomaly was a humdinger. Killed off all their people who knew the ancient language in which their records were kept. They've recently been interpreted by Russian archaeologists.
I didn't know there was solid evidence for this 7th century BC cold spell, but everybody figured there had to be one since so terribly many settled populations pulled up stakes and went somewhere else!
When I got your ping I thought you were discussing British Petroleum...
According to some people, what ain’t? ;’) Thanks BL.
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