Antecedents and self-induction of active-break south Asian monsoon unraveled by satellites

Abstract

Understanding the origin and perpetuation of the monsoon cycle has eluded scientists for decades. Using a suite of unprecedented satellite measurements, we show that the antecedents of the active/break monsoon. emerge in the western equatorial Indian Ocean (EIO). The initiation of a new rainy phase in the western EIO is preceded by in situ surface wind convergence and central EIO warming, both are induced by the subdued condition over the eastern EIO set up in the previous cycle. Thus, a self-induction mechanism appears to be operating in maintenance of the Indian monsoon intraseasonal oscillation. The finding here offers a focus for prediction of the active/break Indian monsoon with potential predictability about four weeks in advance. Copyright 2005 by the American Geophysical Union.