资源环境科技发展态势分析平台

Orbital‐scale Indian Summer Monsoon variability is often interpreted as a direct response to northern hemisphere summer insolation. Here we present a continuous (0‐640 kyr) orbital scale precipitation isotope (δD_precip) record using leaf wax δD from the core monsoon zone of India. The δD_precip record is quantitatively coherent with, and δD_precip minima in phase with, greenhouses gas maxima, and ice volume minima across all orbital bands. The δD_precip record is also coherent and in phase with the two existing orbital‐scale Indian speleothem δ¹⁸O records, demonstrating a consistent regional response among independent proxies. These findings preclude interpretation of Indian precipitation isotope records as a direct response to northern hemisphere summer insolation. Rather, they dominantly reflect changes in moisture source and transport paths associated with changes in greenhouse gases and ice volume. The orbital‐scale precipitation isotope responses of the Indian and East Asian monsoon systems are uncoupled and are driven by different forcings.