This highly technical and scientific paper brings together all the recent evidence from Dharamjali Cave in the Himalayas over a 230 year period around 2000 BCE, when the ancient Indus civilization was in decline, to show "that repeated intensely dry periods spanned multiple generations. The record highlights the deficits in winter and summer rainfall during the urban phase of the Indus Civilization, which prompted adaptation through flexible, self- reliant, and drought-resistant agricultural strategies."