Quantitative contribution of sea surface temperature in three-oceans to the interannual variability of Tibetan Plateau rainfall in boreal summer

Sea surface temperature (SST) is a crucial driver and predictor of the Tibetan Plateau (TP) rainfall anomalies. This study quantified the SST-induced contributions to interannual variability in TP summer rainfall and assessed the relative importance of basins across the three tropical oceans, using atmospheric general circulation model experiments. CMIP6 multi-models’ outputs and Community Atmosphere Model Version 5.3 (CAM5.3) simulations show that global SST explains approximately 20% of this variability, peaking at ~30% in the southwestern TP. SST anomalies primarily affect the TP rainfall via the dynamic process of anomalous moisture transport. While the tropical Pacific SST anomalies dominate TP rainfall variations relative to the Indian and Atlantic Oceans, accurate reproduction of global SST-induced contributions requires treating the three tropical oceans as an integrated system. This underscores the necessity of investigating inter-basin interactions across the three oceans for TP climate change studies.