Analysis of rainfall and temperature variability and trend detection: A non parametric Mann Kendall test approach

The aim of this study was to explore changes in the seasonal and annual rainfall and temperature using time series data of 16 districts of Arunachal Pradesh and to identify trends as an indicator to climate variability in the state. Trends were analyzed using the nonparametric Mann-Kendall test and Sen's slope estimator. The trend analysis indicated that the average annual minimum daily temperature increased over the study period and maximum temperature remained constant. Trend analysis of seasonal minimum temperature showed higher rates of warming in the post-monsoon season followed by monsoon and least in pre-monsoon season. Results revealed that the mean daily minimum and mean daily temperature increased by 0.02 °C/year and 0.01 °C/year, respectively. District wise trend analysis of annual mean rainfall showed decreasing trend for 9 districts and increasing trend in 2 districts and no trend in 5 districts. Annual mean rainfall showed an overall decreasing trend at the rate of 19.23 mm/yr in the state.