Temperature and precipitation records from the Tibetan Plateau matched with the ratio of planktonic to benthic diatoms as an indicator of lake level changes. Peaks in all data occur in the period of the thriving Tibetan Empire in warm and humid conditions, before dramatic changes signify the megadrought coinciding with empire collapse. Following this was the warm-drought of the Medieval Warm Period and then the comparatively wet Little Ice Age. Credit: Chen et al. 2023.