Skip to comments.The Cold Snap That Civilised The World
Posted on 02/23/2002 2:33:42 PM PST by blam
The cold snap that civilised the world
By David Derbyshire, Science Correspondent
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."
#1. The Mediterranean which had been desicated since the Ice Age re-filled?
#2. The same for the Gulf Of Mexico?
I think Noah's Flood was the Black Sea Flood and came only after the Mediterranean was refilled and broke through the Bosphorus. The dates may not work. Good input though.
The worldwide 'long ring' tree ring data indicate a catastropic (worldwide) event at 3195. Could this be your asteroid? Now, where did it hit? (Atlantis?)
Some temples are symbolic, others could be meteorological. Some may have been survey markers. Some may have been schools of science, math, or history.
I'm going to stick with the idea that a change in sea level would change tides and currents like the Gulf Stream and El Nino.
Look at conifer retreat in the North.
On the other hand, the salt layers in the Gulf of Mexico, onshore Texas, Louisinana, Arkansas, and Mexico date back into the Jurassic. They may very well be related to similar salt layers in the North Sea and Germany (called the Zechstein). These were deposited when the continents were in a greatly different configuration, and may record the opening of the proto-Atlantic Ocean (in plate tectonic theory). There is no good evidence to suggest that the Gulf of Mexico, as we know it today, was ever devoid of water.
Another possibility to consider when talking about global climate changes, and/or ocean circulation changes, is the development of the Isthumus at Panama, connecting North and South America, and cutting of the Atlantic and Pacific Oceans at the middle latitudes.
Atuk: Was cold last year.
Atuk: Reckon we oughtta build us a temple. That'll help.
The Mediterranean has been completely dry at least 40 times, the last time was 5 million years ago. I think it was partially dry ( and in sections ) during the last Ice Age. There are scouring marks on the bottom near Gilbralter that hint at a great water break-through, as yet, undated.
I meant to say 3195BC, that would be 5197 years ago. Is that far enough back?
Most likely, if true. More likely: flooding into the Black Sea.
Most likely: A shift of the Gulf Stream southward and/or a shift in the Japanese Current.
Very good input. About the Gulf Of Mexico, I was thinking of a partial water level lowering, not a complete drying. I developed that idea while trying to explain how a city ( as yet unverified ) could be 2,100 feet underwater off the coast of Cuba. (It was built on the shore of a reduced water level Gulf?)
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