Century-scale rainfall variation over Madhya Maharashtra, India

Abstract

IPCC (2007) report says that by the middle of the 21^st Century, available water will reduce by 10-30% causing serious scarcity of fresh water. Madhya Maharashtra meteorological sub-division is one of the significant agricultural regions of the country. In the recent years this region has witnessed extremities in rainfall, and demanding an investigation of rainfall variability. The present study analyses long-term rainfall trends for 120 years (1901-2020) using parametric and nonparametric tests. Madhya Maharashtra has an increasing trend in annual rainfall since 1926. In monsoon all the districts registered rising trend, with three of them being statistically significant. In winter, all the districts except Sangli show decreasing trends which were statistically significant for four districts. Significant change points were found in all the temporal scales (monthly, seasonal and annual). Most importantly the Sequential Mann-Kendall test of the monsoon, as well as the annual rainfall of the districts depict that, except Dhule, Nandurbar, Pune and Kolhapur all the other districts witnessed at least one change point during the last decade. Many of these districts registered their latest change point in last 5 years also. So, a question arises from this observation is that, what will be the scenario of rainfall in these districts in the coming decades and how much will that contribute in changing the overall trend in rainfall over Madhya Maharashtra sub-division as a whole. Future climate prediction till 2100 estimates a mild possibility of an increase in the rainfall extremes in the study area.