Impact of Climate Change on Extreme Drought Events in Ken River Basin, India

Abstract

Global climate change has come to be seen as a major issue confronting the lives of millions of people around the world. Recent erratic weather patterns have been experienced by humans on a regular basis across the world with the Indian subcontinent being no exception. The impacts of climate change include change in the frequency and severity of extreme climatic events resulting in drought and erratic spatial distribution of precipitation. The impacts of regional climatic change on the frequency and severity of monthly, seasonal, and annual drought events in Ken River Basin in central India are investigated in this study. The basin experiences semi arid to dry sub-humid climate with a single rainy season (June-September), contributing approximately 90% of rainfall, followed by dry winter, and then a very dry summer. Analysis of long term monthly rainfall data of 12 raingauge stations for the period of 102 years (1901-2002) revealed that during first half of the study period, the basin faced drought event 5 times, however, in second half of the study period, the frequency of drought is much higher with average recurrence of once in every 5 years. Also, decadal average annual and seasonal rainfall trend analysis shows declining trend in rainfall during the study period which is an indication for likely increase in occurrence of drought events in coming future. The maximum annual and seasonal rainfall departures (deficiency) have been recorded of the order of - 53% and -61% of respective mean value at Banda station during 1991. The 3-month duration Standardized Precipitation Index (SPI) calculated for the entire period shows that severity of drought is likely to increase during July to October month for all stations, which could be attributed to climate anomalies.