Trends of Rainfall in Different Sectors of Uttar Pradesh Under Present Scenario of Climate Change

Abstract

In the changing scenario of climate, the present study was carried out to identify the recent trends of rainfall variability in different sectors of Uttar Pradesh. Analysis of rainfall (1971-2011) was made for four sectors viz. Eastern, Western, Central and Bundelkhand region of U.P. It was found that in general, annual rainfall decreased in all sectors of U.P. but the rate of decrease of rainfall in western U.P. was faster as compared to other sectors of U.P. and was in the order of Western U.P.> Eastern U.P.> Central U.P.> Bundelkhand region. Variability of seasonal rainfall in different sectors of U.P. was also in the same order and magnitude as that of total rainfall. Average onset dates of south west monsoon in Eastern U.P. and Wentral U.P. have shifted to 19th/and 20th June respectively, from the normal date of 15 th June. Total rainfall in relation to onset of monsoon, decreased by 6%, if monsoon reaches on 19th June in Eastern U.P.( normal date of onset is 15th June) and 9.5%, if monsoon reaches on 25th June. Consequent upon length of rainy season was also decreased from normal 108 days to 99 days in Eastern U.P. whereas reduction in length of rainy season in other sectors of U.P. ranged between 12-13 days. Rainy day and rainfall intensity both reduced in all sectors of U.P. In Eastern U.P. rainfall intensity reduced from 25 mm/day (1971-1990) to 17.2 mm/day (1992-2011), i.e. 32% reduction, hence crop planning may be made accordingly in respective sectors.