Reversal nature in rainfall pattern over the Indian heavy and low rainfall zones in the recent era

This study presents the reversal nature in rainfall over heavy rainfall zone (HRZ; more than 80% of the long period average (LPA) of the Indian summer monsoon rainfall (ISMR)) and low rainfall zone (LRZ; less than 40% of ISMR-LPA) in India. The India Meteorological Department (IMD) high-resolution (0.25° × 0.25°) dataset is used from 1901 to 2016. The single and multiple change-point detection techniques are used to find the change in rainfall patterns over both regions. Further, the study period is divided into two halves P1 (1901–1958) and P2 (1959–2016) to examine the change in rainfall patterns in the recent and past periods. In P2, the rainfall pattern gets reversed, and ISMR has shown a significant increasing (decreasing) trend over the LRZ (HRZ). The increasing/decreasing number of moderate- and high-intensity rainfall events is one of the causes for this reversal pattern. Additionally, the number of dry days is increased over the HRZ and decreased over the LRZ. This study further confirms that the “dry becomes drier and wet becomes wetter” paradigm is not solely acceptable for India. The present study provides information about changes in dry days and ISMR variability in the context of climate change, which will be useful to agricultural risk management, water resources, drought monitoring, model developers, and policy planner on the adaptation strategies for climate change.