Trend Analysis of Meteorological Variables and Drought Indices in the Bundelkhand Region using the Non-Parametric Approach

A. Vishwakarma, M. K. Choudhary, M. S. Chauhan

Droughts significantly decrease production of crops. Therefore, three drought indices, SPI and SPEI (Meteorological drought) and SSI (Agricultural drought) have been evaluated for 82 rain gage stations in the Bundelkhand region, India. The non-parametric trend test (the Mann–Kendall test) and the Sen’s slope estimator have been used to analyze the monthly, seasonal, and annual trends for both categories of drought. Monthly and annual trends of rainfall and temperature (both minimum and maximum) have also been analyzed for the study area. The analysis revealed the negative trend of SPI mainly for the northern part of Bundelkhand and especially for monsoon season and for August– September. The trend for precipitation amount is also negative for these months. The minimum tempera- ture has increased (0.03 to 0.07C/year) more as compared to the maximum temperature (< 0.01C/year with an insignificant trend). PET was evaluated using the Penman–Monteith method for the further calculation of SPEI. The inverse distance weightage (IDW) method of interpolation has been used to represent the trends on ArcGIS.