Climate History Network

An article recently published in the Proceedings of the National Academy of Sciences (also reported here in Science Daily News) makes the case that weakening monsoons and growing aridity likely played a decisive role in the abandonment of the Indus Valley (or Harappan) civilization ca.1900 BC.  The 2003-08 international study, combining geomorphology and archaeology, suggests that the civilization flourished during a critical period of declining monsoon rains, while the river Indus river system was stable enough to avoid destructive flooding, but before it became too arid for agriculture to support dense populations.  The authors suggest that the population could have gradually abandoned the region for the wetter and more fertile Ganges Valley.