Trends in precipitation extremes over central India

Abstract

Climatic characteristics of occurrence of extreme rainfall events over central India are studied by using about 100 years of daily rainfall data. The time series comprising of daily rainfall data set 350 stations in the Central parts of India (comprising of the states Madhya Pradesh, Chattisgarh and Vidarbha) for the period 1901 - 2010 have been analysed. The daily rainfall (rf) has been classified under the categories of (i) 7< rf < 12 cm, (ii) rf ≥ 12 cm and (iii) annual extreme (24 hourly rainfall) and their events, patterns and significance have been examined. It is seen that the long-term does not indicate any trend in the monsoon seasonal (June to September) rainfall; however there are decreasing and increasing trends in the extreme rainfall (≥7cm) events. The composite charts of frequency of occurrence of extreme rainfall events located in various geographical areas have been prepared and thereby identifying the possible highest rainfall areas over central India. The synoptic weather systems responsible for the extreme events over central India were also examined and discussed in this paper.