TR-4 : Statistical analysis of rainfall in Belgaum district, Karnataka

Abstract

Belgaum district in Karnataka has been experiencing drought continuously for the past few years. To study the phenomenon of low rainfall in the district, statistical analysis of monthly and annual rainfall data of raingauge stations located in the district and neighbouring Bijapur and Dharwar observatories has been carried out. Besides studying the cross correlation of rainfall in monsoon months and serial correlation, other techniques like linear regression and polynomial regression have also been applied to identify the presence of any trend.

There was no relation between the rainfall in each of the monsoon months and the monsoon total, and among the rainfall of the monsoon months. Also, the serial correlation was poor indicating the absence of any persistence in the series. Linear regression of rainfall data for Belgaum observatory on split sample data has indicated a falling trend in recent years.

A comparison of the Malaprabha catchment rainfall and flow data showed good agreement. There was no decreasing trend in the Malaprabha catchment rainfall. Polynomial regression of the rainfall series has indicated some trend in the rainfall series of Khanapur, Hukeri and Bijapur.