Analysis of the Extreme Rainfall Events Over Upper Catchment of Sabarmati River Basin in Western India Using Extreme Precipitation Indices

Abstract

Analysis of extreme rainfall events provide an idea of the probable occurrence of such events in future, and catchment response to such events can be utilized for assessing the flood characteristics of the river basins. This study focuses on the analysis of the extreme precipitation events in the upper catchment of Sabarmati River in western India. Extreme precipitation indices such as the number of rainy days, annual precipitation, daily intensity index, consecutive wet spells, one-day maximum rainfall were calculated as per the norms suggested by Expert Team on Climate Change Detection Monitoring and Indices (ETCCDMI) of Intergovernmental Panel on Climate Change (IPCC). These precipitation extremes were analysed using the IMD gridded precipitation datasets, and associated flood characteristics of the river basin were analysed with the available daily streamflow data for the period 1992–1994. This chapter explains the spatial variation in extreme rainfall events and its effect on the streamflow of the river. Finding of the study reveals no significant trend in the extreme rainfall events of the basin, but catchment response to the extreme rainfall events is evident which could be verified with longer period streamflow data analysis.