Ocean-atmosphere interaction and the variability of the South Asian monsoon

There are clear, if ambiguous indications that remote ENSO-related SST anomalies influence the interannual variability of the South Asian monsoon. The ambiguity comes from the very large interdecadal variability of the ENSO-monsoon relationship. On the other hand, there are strong regional negative feedbacks between the atmosphere and the ocean that conspire to minimize the magnitude of the seasonal cycle and impart a strong biennial aspect to the interannual variations of the monsoon. We will demonstrate how these feedbacks arise and how the Indian Ocean Zonal Mode is an integral part of the feedback system. But how the regional feedbacks interact with the remote ENSO forcing is less clear. The aim of this paper is to build a holistic view of the complete monsoon system including both regional and remote impacts.