Detection and Attribution of Climate Change over the Tibetan Plateau

We assess the relative roles of anthropogenic forcing and natural variability in recent climate change over the Tibetan Plateau using D&A frameworks. First, optimal fingerprinting applied to CMIP6 simulations and multiple observational datasets (stations and ERA5) quantifies seasonal changes in extreme precipitation indices (Rx1day and Rx5day) over 1961–2020. Anthropogenic signals are robustly detected in the increasing trends of spring and winter extremes, whereas natural forcing is not detected in these seasons. Second, we attribute the record-breaking 2022 compound hot–dry event using high-resolution statistically downscaled CMIP6 simulations and a Copula-based joint-probability framework to estimate return periods and risk ratios. Results indicate that human influence substantially amplifies the likelihood of extreme heat, drought, and their concurrence, and projections suggest a further increase in compound-event risk. Together, these lines of evidence show that anthropogenic forcing is a dominant driver of both long-term extreme changes and recent high-impact compound events over the Tibetan Plateau, providing actionable information for disaster risk management and adaptation planning in ecosystems, agriculture, and infrastructure.