Mughal empire

In a remote cave in northeast India, rainwater has slowly dripped from the ceiling in the same spots for over 1,000 years. With each drop, minerals in the water accumulate on the floor below, slowly growing into calcium carbonate towers known as stalagmites. These stalagmites are more than geological wonders – like tree rings, their layers record the region’s rainfall history. They also carry a warning about the potential for catastrophic multiyear droughts in the future. By analyzing the geochemistry of these stalagmites in a new study published Sept. 19, 2022, in the Proceedings of the National Academy of Sciences, we were able to create the most precise chronology yet of the summer Indian monsoon over the past millennium. It documents how the Indian subcontinent frequently experienced long, severe droughts unlike any observed in the last 150 years of reliable monsoon rainfall measurements. The drought periods we detected are in striking synchrony with historic...