Trend analysis of rainfall in Bharathapuzha River basin, Kerala, India

摘要

Knowing the variations in the general rainfall pattern of a river basin is vital to understanding the hydrological cycle and water budget of the basin. The present study examined the general rainfall pattern in Bharathapuzha River basin of Malabar coast of Kerala, using monthly rainfall data for 34 years collected from 28 rain gauge stations. We used Mann-Kendal's rank correlation statistics and wavelet analysis to examine the trend of rainfall. The annual rainfall, southwest monsoon, and pre-monsoon rainfall of the basin shows a significant decrement towards the later years of the study. We assume that the global climate and the local environmental changes are the chief factors for the variation.