Weather analysis through Mann-Kendall test and other applications

Abstract

The present study analyzed changing trends of rainfall and temperature of the Raichur region which belongs tothe North-Eastern dry zone of Karnataka, India. Normal climatic variables including rainfall, rainy days and temperaturerecorded over 35 years were analyzed. The data has been processed to find out the monthly variability which is part of non-parametric Mann-Kendall test. Further, it has been used together with Sen’s slope estimator for the determination of trendand slope magnitude for time series data. Rainfall data analysis has shown a decreasing trend (732 to 622 mm) in all theseasons except summer with a coefficient of variation as 29%. Mean monthly maximum temperature was found to have adecreasing trend (34.3 to 34.00 C) over years whereas, the monthly minimum temperature was found to have an increasingtrend (20.5 to 21.10 C). The annual temperature trend has indicated that there was no significant difference during the periodof observation except forthe post-monsoon season. Number of rainy days was reduced (41.9 to 36.3) in all the seasons dueto spatio-temporal variability. Results from this study would serve as a guide for future yield predictions, crop simulationmodels, crop planning, and agriculture practices in the region.