Posted on 02/23/2002 2:33:42 PM PST by blam
The cold snap that civilised the world
By David Derbyshire, Science Correspondent
(Filed: 22/02/2002)
A SUDDEN drop in temperatures 5,000 years ago ushered in the modern climate and may have encouraged the development of complex civilisations around the world.
Researchers studying ancient fish bones off the coast of Peru say the temperature fall heralded El Nino, the periodical warming of the Pacific which brings unusual weather patterns every two to seven years.
The rapidly changing weather, which followed several thousand years of post-Ice Age stability, triggered a new temple building culture in South America. Elsewhere, it may have forced Stone Age people to innovate, generating a period of development and the formation of large cities.
Scientists at the University of Georgia and the University of Maine looked at otoliths, tiny sensory structures in the inner ears of fish that grow in alternating opaque and translucent bands by amounts that reflect sea temperatures.
They report in Science that, before 5,000 years ago, sea temperatures off Peru were around four degrees warmer than they are today.
Suddenly, sea temperatures fell and the cycle of El Nino appeared. In normal years, prevailing winds push warmer surface waters to the Australian side of the Pacific. Cold water from the deeps rises to the surface off Peru. The Americas are dry, while monsoons hit southern Asia.
During El Nino years, however, severe floods and storms hit the west coast of America, while Asia suffers drought.
Although El Nino's arrival made the climate unstable, cooler weather in the intervening years increased the number of small fish and shellfish off America.
The effects of this may have been dramatic, triggering people living on the coast of Peru to build large temples and develop a more complex culture. The same spurt of climate-related development may have taken place across the world.
In Egypt, the drying of southern Egypt west of the Nile may have forced herders to move into the Nile valley, where the ancient Egyptian civilisation emerged a few hundred years later.
Dr Elizabeth Reitz, of the University of Georgia, said: "A change in El Nino frequency and the related increase in upwelling about 5,000 years ago may be related to changes in fishing resources and increased cultural complexity."
Dr Fred Andrus, of the University of Georgia, said: "Our data strengthen the argument that El Nino as we know it began relatively recently, since 5,000 years ago.
"This is more evidence that climate change is the norm, and climate stability is the exception in the Earth's history, even in relatively recent times.
"Given the enormous global impact of El Nino, it is important to understand that climate is a naturally variable system."
Okay. I have catastropic (worldwide) tree ring events at 2354BC (start bronze age), 1628BC (The Exodus), and 1159BC (David Plague),and 207BC (minor event). Will any of these work?
"Venus had a psychological effect upon the Maya and other Mesoamerican cultures, it has been shown that the Maya were timing some of their wars based on the stationary points of Venus and Jupiter. Humans were sacrificed on first appearance after Superior Conjunction when Venus was at its dimmest magnitude but they most feared the first Heliacal Rising after Inferior Conjunction." Quoted from This site
My Brother and I have been discussing that possibility recently. Do you have any reference data or links?
I know, 5 million years to be exact. I'm arguing for a 'reduced water level' in the Mediterranean. Click on the link in post #21. See that the Meditteranean is 'sectioned' across Italy/Sicily/Africa with just a 360 foot water drop.
Some think the worlds oceans dropped by 500 ft.
After the last Ice Age, the water crashed through Gilbralter 'dam' then the Italy/Sicily/Africa 'dam' and then the 'dam' at the Bosphorus flooding the Black Sea. Also, notice on the map, no Persian Gulf and a landlocked Red Sea. (Note similar possibilities in the Gulf Of Mexico). This 'refilling' would sure make for a lot of 'flood' stories, huh?
There are some PhD friends of my son (Dr. blam) in SOCAL who are looking into the possibility but, other than a flurry of emails, I've not seen anything published on the subject.
So, you're looking for an event centered around +- 3500BC? I'll keep my eyes open.
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