A civilization that occupied areas of modern-day Pakistan and India may have declined, at least in part, due to an extreme bout of climate change, researchers at the University of Cambridge argue in a study.
This is not to say that the event was brought on by global, or even localized, warming, but by an abrupt weakening of the summer monsoon, which occurred 4,100 years ago. The traces left behind by this event are visible even now, the research team reveals in a paper published in the journal Geology.
The weak summer monsoon affected northwest India the most, and led to significant droughts that most likely created widespread famine. Even if a direct causal link is not found between this event and the decline of the Indus Civilization, the fact remains that the two phenomena coincide remarkably well.
Unlike other cultures, the Indus Civilization was capable of building metropolises, and spanned parts of northern India and most of modern-day Pakistan. The conclusions in this new study may suggest that climate change is one of the main reasons why many large, ancient cities fell into ruin.
http://news.softpedia.com/news...Decline-429730.shtml
<big class="storyhed">Climate Change Linked to Civilization Collapse</big>
Jen Mapes
National Geographic News
(February 27, 2001)
Two scientists have linked climate variations to the collapse of societies around the globe. Sometimes slight, sometimes intense, the scientists argue in a recent issue of the journal Science that the changes were enough to forever alter the lifestyles of the people living under changed conditions.
A Culture Killer
An article in a 1995 issue of Nature pointed to drought as one cause of the demise of the Maya civilization. Its writers argued that internal factors, including population growth and environmental degradation, worked with climate change and led to the Maya collapse.
Last month's Science article, coaut****d by Harvey Weiss of Yale University and Raymond Bradley of the University of Massachusetts at Amherst, explored other prehistoric, ancient, and premodern societies, and found natural climatic variations often corresponded with the societies' collapse.
In Mesopotamia, a canal-supported agricultural society collapsed about 3,400 years ago. The paleoclimatic record, write the authors, suggest a severe 200-year drought may have caused the society to collapse.
With wetter conditions, civilizations thrived in the Mediterranean, Egypt, and west Asia. Ten years after their economic peak in 2300 B.C., however, catastrophic drought and cooling hurt agricultural production and caused regional abandonment and collapse.
http://news.nationalgeographic...2/0227_climate4.html
When has the climate not changed?