Thread by @weatherindia

Major flooding and drought events caused by abnormal monsoon patterns may have been responsible for wiping out powerful medieval dynasties across the Indian subcontinent 7 to 8 centuries ago, a new study has found.

Read: weather.com/en-IN/india/sc…

📸: Rahul Gayakwad/BCCL Kolhapur

Evidence for the same was discovered by a group of geology experts from IIT Kharagpur, who spent years studying oxygen isotopes on the ancient stalagmites located in Meghalaya’s Wah Shikar Caves. @IITKgp

While the stalagmites are 1,000 years old, dating of the isotopes revealed evidence of heavy and low precipitation from 900 years ago, occurring b/w 1100 AD and 2012 AD. Further analysis showed abrupt shifts in Indian summer monsoon; this led to a huge impact on human societies.

The paper says that the monsoon was strong during the Medieval Climate Anomaly (1100AD-1300AD) and the Current Warm Period (1750AD-present), and showed multiple shifts during the Little Ice Age (1300AD-1750AD).

"Intervals of prolonged summer monsoon weakening are correlated to the decline of major dynasties in India, possibly due to decrease in agriculture productivity, declining economy and societal crisis," reads the paper.

Sena in Bengal, Solanki in the west, and the dynasties of Paramar, Yadav and Pandyan from the south were among the ones that met their end during these extreme, catastrophic events.

The study adds that similar events may also have occurred in China, thereby leading to the downfall of the Ming dynasty.

So far, the existent history has led us to believe that wars were the only major factors to have caused the downfall of great dynasties. But now, this study has offered a new, unique perspective that could provide better values to the existent explanations.

Not only have its findings reported new flooding and drought events that were never recorded in history, but the study also sheds more light on some already-known events related to migration and the beginning- and end-dates of dynasties.