Long-Term Trend Analysis of Rainfall Data of Sirsa Districts of Haryana

Abstract

The trend analysis of rainfall data is important aspect to understand the changing rainfall pattern in a given region over a long period of time. The Sirsa district of Haryana has a predominantly agriculture based economy. The agricultural activity is mainly dependent on rainfall. In India, most part of total annual rainfall occurs in monsoon so the occurrence of rainfall is unpredicted and erratic which produces an adverse effects on the cropping system. In addition this, the changing climate is also known to affect the rainfall pattern in the Indian subcontinent. At this very outset the present study focused on the statistical analysis of rainfall data for analyzing changing trend in past   114 years of a Sirsa District. Rainfall data of  114 years (1901-2014) was processed at various time steps such as  monthly,  seasonally  and  annual to analyze the rainfall  variability and trend  by  using descriptive statistics, linear regression and nonparametric  analysis. The nonparametric Mann-Kendall (MK) Test and Sen’s slope Estimator indicated varied degrees of trends and magnitude of change in rainfall pattern over the studied period. The major finding of the analysis was an increasing trend in rainfall at annual time step. An increasing trend were also observed for  pre-monsoon and post-monsoon seasons and for the months May, June, November at monthly time step.  The findings will help in deciding the optimum cropping pattern and irrigation scheduling ensuring the efficient water usage in the study area.