Higher sea surface temperature in the Indian Ocean during the Last Interglacial weakened the South Asian monsoon
Yiming V. Wang, Thomas Larsen, Stefan Lauterbach, Nils Andersen, Thomas Blanz, Uta Krebs‐Kanzow, Paul Gierz, Ralph R Schneider
Abstract
SignificanceUnderstanding the drivers of South Asian monsoon intensity is pivotal for improving climate forecasting under global warming scenarios. Solar insolation is assumed to be the dominant driver of monsoon variability in warm climate regimes, but this has not been verified by proxy data. We report a South Asian monsoon rainfall record spanning the last ∼130 kyr in the Ganges-Brahmaputra-Meghna river catchment. Our multiproxy data reveal that the South Asian monsoon was weaker during the Last Interglacial (130 to 115 ka)-despite higher insolation-than during the Holocene (11.6 ka to present), thus questioning the widely accepted model assumption. Our work implies that Indian Ocean warming may increase the occurrence of severe monsoon failures in South Asia.