On the basis of past 115 years (1901-2015) rainfall data of three districts of south Gujarat, the Mann-Kendall trend and Sen’s slope analysis was done in different four era of thirty years (e.g. 1901-30, 1931-60, 1961-90 and 1991-2015). Results showed that annual standard precipitation index at Dang shows the increasing trend in all the era while, that of Navsari and Valsad districts are declining trends in two era (1901-30 and 1931-60) and increasing in two era (1961-90 and 1991-2015). The pre monsoon season standard precipitation index of Dang district shows decreasing trends in all era whenever, Navsari and Valsad districts was recorded decreasing trends in two era (1901-30 and 1961-90) and increasing trends in remaining two era (1931-60 and 1991-2015). In case of south west monsoon Dang and Valsad district showed most frequently increasing trends in almost all of the era same as Navsari district showed the decreasing trends in standard precipitation index in most of the era. The Navsari district showed increasing trends in most of the era while, Dang and Valsad districts showed declining trends in standard precipitation index in most of the era in case of north-east monsoon. Analysis of standard precipitation index of winter season revealed that all the districts showed the decreasing trends in all the era except one era (1901-30).

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