Indian-origin scientist narrows down on the decline of the Indus Valley Civilization


A new study by an Indian-origin scientist shows how the ancient Indus Valley Civilization (Above photo)may have come to an end. And it reveals a similar issue we at this current generation are facing – climate change.

Nishant Malik

Nishant Malik, Rochester Institute of Technology researcher developed a mathematical method that shows climate change likely caused the rise and fall of an ancient civilization.

In an article recently featured in the journal Chaos: An Interdisciplinary Journal of Nonlinear Science, Nishant Malik, assistant professor in RIT’s School of Mathematical Sciences, outlined the new technique he developed and showed how shifting monsoon patterns led to the demise of the Indus Valley Civilization.

Malik developed a method to study and measure the presence of particular chemical forms in stalagmite mineral deposits in caves in South Asia, scientists could develop a record of monsoon rainfall in the region for the past 5,700 years.

However, Malik said studying ancient climate time series with mathematical tools typically used to understand climate is a challenging task.

“Usually the data we get when analyzing paleoclimate is a short time series with noise and uncertainty in it. As far as mathematics and climate is concerned, the tool we use very often in understanding climate and weather is dynamical systems,” Mr. Malik said.

“But dynamical systems theory is harder to apply to paleoclimate data. This new method can find transitions in the most challenging time series, including paleoclimate, which are short, have some amount of uncertainty and have noise in them,” he explained.

While there are several theories about why the Indus Valley Civilization declined, including invasion by nomadic Indo-Aryans and earthquakes, climate change appears to be the most likely scenario, the study noted.

But until Malik applied his hybrid approach — rooted in dynamical systems but also draws on methods from the fields of machine learning and information theory — there was no mathematical proof. His analysis showed there was a major shift in monsoon patterns just before the dawn of this civilization and that the pattern reversed course right before it declined, indicating it was in fact climate change that caused the fall.

Malik said he hopes the method will allow scientists to develop more automated methods of finding transitions in paleoclimate data and leads to additional important historical discoveries.


[Photos courtesy:Credit:  Rochester Institute of Technology (RTI)]