LAUSR

AbstractThe onset of the South Asian summer monsoon (SASM) indicates the beginning of the rainy season in the South Asia region. It is not only critical for the local agriculture and animal husbandry but also important for water and life security. Precipitation in the early rainy season (May) increases rapidly and has a large interannual variability, especially in the Tibetan Plateau (TP) region. One of the starting mechanisms of the monsoon system is the land–sea thermal contrast (LSTC) between the Indian Ocean (IO) and South Asia region. Therefore, the IO can be considered as a crucial factor for the intensity of the monsoon system, as well as the TP precipitation. In this study, the relationships between IO sea surface temperature (SST) and TP precipitation on the interannual time scale are investigated. Correlation maps show that IO SST variability contains a portion that is independent from the tropical Pacific Ocean SST and is negatively correlated with the TP precipitation. Here the authors define ...