Decadal Variability in Synchronization of Extreme Precipitation During the Indian Summer Monsoon

Indian subcontinent receives over 70% of its annual precipitation during the monsoon period i.e., June, July, August, and September. As a consequence, the monsoon causes large socio-economic impacts including the potential threat of flooding by extreme precipitation. Therefore, it is essential to understand the evolution and spatial-temporal dynamics of extreme precipitation. However, understanding of long term synchronization in extreme precipitation events and its decadal variability is lacking. Here, we exploit complex networks to identify the spatiotemporal patterns of extreme precipitation to understand the underlying dynamics of the associated weather processes. We use a nonlinear measure of synchronization of extreme precipitation events to define networks during the Indian summer monsoon development using 0.25 0.25 high-resolution gridded data from Indian Meteorological Department (IMD) for a period of 120 years (19012020). We examine the decadal variation of synchronization in extreme precipitation during the Indian summer monsoon (ISM). Our results show the North west and West Central regions of India undergo a repetitive pattern during the ISM (while analyzing decadal variability). Further, the strength of synchronization is the reason for increased frequency of extreme events. These observations will be useful to predict the timing and strength of ISM.