Sarasvati Civilization

[Husky]

This may belong here. Forgot. Though people would probably have already seen it. Last year's New Scientist.

On Saraswati-Sindu Civilisation (SSVC), neutered as "IVC" by christian history-writing.



newscientist.com/article/mg22129613.700-withering-monsoon-may-have-doomed-past-asian-society.html#.VL3tcyzudv8

Withering monsoon may have doomed past Asian society



19 March 2014

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RAIN, rain, go away. The Indian summer monsoon abruptly weakened 4200 years ago. The ensuing drought may have led to the collapse of the Indus Valley Civilisation.



This lost society flourished around the Indus river, in what is now Pakistan and north-west India. It was at its height from 2600 BC to 1900 BC, but after that its cities were mysteriously abandoned.



Yama Dixit and her colleagues at the University of Cambridge dug up snail shells from Kotla Dahar, a lake near one of the cities. The shells record changes in the lake's water level in their composition.



The team found that the lake was deep from 4500 to 3800 BC. Although it shallowed a little up to 2200 BC, after this time there was a sharp drop in the water level, suggesting the summer monsoon abruptly weakened for 200 years, meaning less rainfall (Geology, doi.org/rvt).



(The collective memory/oral traditions of Saraswat brahmanas of leaving Saraswati area upon a drought, before they then branched out in time. I can't remember whether they dated it to 4000 BCE or 4000 BP. But is this first migration of the SBs related to the events of the above period?

But the overlap of the long-standing oral tradition with the area and events certainly does add lots of quaint question-marks to the whole AIT/AMT/ATT scenario of - when was it now - what's variously dated to 1800 BCE to 1100BCE to even 900 BCE.

And also, the recently-invented ideology/religion "dravoodianism" has NO memory of actual being at the Saraswati-Sindhu region let alone of any drought. And it's too late to attempt back-projection too.)



The Indus valley people relied on the monsoon for crops, says Dixit. "It is inevitable that they were affected." The dates of the drought don't match perfectly with the collapse, but Dixit says both are uncertain.



The idea is credible because the results agree with data elsewhere, says Supriyo Chakraborty of the Indian Institute of Tropical Meteorology in Pune.



Shifts in the monsoon have also been linked to the fall of China's Tang dynasty, and of the Mayan civilisation in South America, both around AD 900.



This article appeared in print under the headline "Withering monsoon may have doomed past society"

Full-length version:



newscientist.com/article/dn25219-withering-monsoon-may-have-doomed-past-asian-society.html#.VL3tgSzudv8

Withering monsoon may have doomed past Asian society



17:39 13 March 2014 by Sandhya Sekar

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The Indian summer monsoon abruptly weakened 4200 years ago. The ensuing drought may have led to the collapse of the advanced Indus Valley Civilisation.



A complex society flourished on the banks of the Indus river, located in what is now Pakistan and north-west India, and was at its height between 2600 BC and 1900 BC. Cities like Harappa and Mohenjo-daro were well planned, and the society even developed its own script. But after 1900 BC, the cities of the Indus Valley Civilisation were gradually abandoned. Nobody knows why.



Yama Dixit and her colleagues at the University of Cambridge excavated in Kotla Dahar, a lake close to one of the civilisation's greatest cities, Rakhigarhi in Haryana. They unearthed the shells of snails called red-rim melanias, and used them to reconstruct changes in climate over the last 5000 years.



The snails use oxygen from the lake water to make their shells. But when water evaporates from the lake, the lighter form of oxygen, oxygen-16, is lost to the air and heavier oxygen-18 builds up. So shells with more oxygen-18 reflect periods of drought.



End times



Dixit found that Kotla Dahar was a deep freshwater lake between 4500 and 3800 BC. It then started getting shallower, until about 2200 BC, when the summer monsoon suddenly weakened for 200 years.



That would have been bad news for the people living there. The Indus Valley Civilisation depended on the monsoons for their crops, says Dixit. "It is inevitable that they were affected by a pronounced drought of this kind."



The dates of the drought do not match perfectly with the date of the collapse, but Dixit says both figures are quite uncertain.



By itself, the lake is not representative of the entire civilisation, says Supriyo Chakraborty of the Indian Institute of Tropical Meteorology in Pune. "But the authors have compared their results with various other observations and found agreement, giving credence to their claim," he says.

Global drying



It is not the first time shifts in the monsoon have been linked to the collapse of civilisations.



Around AD 900 one of China's biggest empires, the Tang dynasty, collapsed. At the same time, halfway across the world, the Mayan civilisation in South America all but disappeared. Records from a lake in China show that stronger winds made the summer monsoon fail, causing widespread drought.



Dixit says the drying events at AD 900 and 2200 BC were both linked to shifts in the position of the Intertropical Convergence Zone, a band of cloud that runs east to west in the tropics and has a big influence on rainfall. "These climate phenomena were not regional but global in nature," she says.



Journal reference: Geology, DOI: 10.1130/G35236.1

connection.ebscohost.com/c/articles/95089290/withering-monsoon-may-have-doomed-past-society