Assessment of Annual, Monthly, and Seasonal Trends in the Long Term Rainfall of the Garhwal Himalayas

Abstract

Climate change is one of the very significant apprehension argued in the recent two decades. Its influence on rainfall has brought in considerable attention worldwide. Hence, this chapter focuses on assessing the trends in the rainfall during 1901-2012 in the Dehradun, Haridwar, Uttarkashi, Tehri-Garhwal, Pauri-Garhwal, Rudraprayag and Chamoli districts of the Garhwal Himalayas by applying non-parametric Mann-Kendall and the Theil-Sen's Slope Estimator tests for the determination of trend and its magnitude. The findings revealed a statistically significant positive trend in annual and monthly rainfall (May and July) of Dehradun district. Rainfall shows a statistically significant positive trend in May (Haridwar and Tehri Garhwal) and a significant negative trend in January (Uttarkashi and Chamoli). On the other hand, Pauri Garhwal and Rudraprayag indicates no significant trend in monthly rainfall. An insignificant trend has also been observed in seasonal rainfall of most of the districts. Annual, monthly and seasonal rainfall shown no particular pattern in the region.