Indus Valley Civilization Collapsed Because Of Climate Change

It was recently discovered that the likely collapse of the Mayan inland centers were probably due to shifting trade patterns rather than climate change as previously thought. Another great civilization, the Indus Valley or Harappan civilization, however, probably did collapse 4,000 years ago thanks to change in climate, according to a new study.

The study indicates that the aridification of the land of the Indus, and the dwindling rivers correlated with the dying out of the great civilization.

Although lesser known than the more famous Egypt or Mesopotamia, the Indus Valley civilization was one of the largest, covering over 385,000 square miles. Their territory extended into what is now northwest India, Pakistan, and eastern Afghanistan. Like Egypt and Mesopotamia, the Indus Valley civilization valued rivers highly, choosing to live by them and utilize the fertility of the surrounding lands.

"We reconstructed the dynamic landscape of the plain where the Indus civilization developed 5200 years ago, built its cities, and slowly disintegrated between 3900 and 3000 years ago," said Liviu Giosan, a geologist and lead author of the study. "Until now, speculations abounded about the links between this mysterious ancient culture and its life-giving mighty rivers."

The research was done in Pakistan, from the coast of the Arabian Sea into the irrigated valleys of Punjab and the northern Thar Destert. It included collecting sediment samples through various means, even manual drilling and analyzing satellite and topographical photos.

The scientists were then able to recreate approximately 10,000 years of the landscape and correspond it with where they knew the Indus Valley civilization lived at the times.

Around 3,900 years ago, the rivers began dying, and the Harappans moved eastward.

"We can envision that this eastern shift involved a change to more localized forms of economy: smaller communities supported by local rain-fed farming and dwindling streams," said Fuller. "This may have produced smaller surpluses, and would not have supported large cities, but would have been reliable."

The spreading out of the population did not fit well for the Indus civilization, who were used to surpluses and urban environments. The lack of large cities meant agriculture continued, but many key marks of a great civilization such as art and writing faded away.