Ecology, Environment and Conservation Paper


Vol 31, 2, 2025

Page Number: 739-744

TREND DETECTION IN RAINFALL USING THE MANN-KENDALL TEST OVER A PERIOD OF FOUR DECADES: A CASE OF BHUBANESWAR CITY IN ODISHA

Binodini Majhi

Abstract

This study investigates rainfall variability and trends in Bhubaneswar city using daily rainfall data from 1970 to 2015, sourced from the India Meteorological Department (IMD), Pune. The research employs the Mann-Kendall Test and Sen’s Slope Estimator to identify trends in rainfall patterns over the 46-year period. The results show that August records the highest average monthly rainfall, with a mean of 370.78 mm and a standard deviation of 127.92 mm. However, a declining trend in rainfall is observed for seven out of twelve months, including August. Notably, the trend for August is statistically significant, with a Mann- Kendall (MK) test value of -2.225 and a P-value of 0.027, indicating a significant decrease in rainfall over time. These findings suggest potential implications for water resource management and urban planning in Bhubaneswar, highlighting the need for adaptive measures to cope with changing rainfall patterns.