A groundbreaking paleoclimate study published this week uses oxygen isotope data from stalagmites in Himalayan caves to reconstruct the monsoon patterns of the 3rd millennium BCE. The findings show a sudden, 200-year-long megadrought that coincided exactly with the abandonment of major Harappan cities like Mohenjo-daro.
The research suggests that the Harappan civilization did not disappear but rather migrated toward the Ganges valley in search of reliable water sources. This shift from urban to rural settlement patterns was an adaptive strategy in response to severe environmental stress, rather than the result of invasion.