Two decades of climate cropping patterns and groundwater change in semi-arid northwestern India.

Groundwater is essential for agricultural sustainability in semi-arid regions; however, the seasonal dynamics of depletion, particularly their relationship with cropping cycles and climate variability, remain insufficiently explored at regional scales. This study addresses this gap by conducting a two-decade (2001-2020) spatio-temporal analysis of pre- and post-monsoon groundwater fluctuations in Kurukshetra, India, using GIS-based Inverse Distance Weighting (IDW) interpolation. We integrated climatic variables (precipitation and evapotranspiration) and the Normalized Difference Vegetation Index (NDVI) to evaluate their influence on groundwater dynamics. The results reveal a significant long-term decline in groundwater levels (R² = 0.74, p < 0.01), with pronounced declines during the Rabi season, with average pre-monsoon drops of 18.6 m and post-monsoon drops of 21.7 m. NDVI correlated negatively with groundwater levels (pre-monsoon r = -0.14, post-monsoon r = -0.45; both p < 0.001), cumulative average drops of 18.6 m (pre‑monsoon) and 21.7 m (post‑monsoon) over the 20‑year period. A linear trend model fitted to the district‑average groundwater levels yielded R² = 0.74 (p < 0.01), indicating a strong long‑term declining trend, indicating intensifying agricultural pressure on aquifers. Precipitation was not a significant predictor in the post-monsoon model (p = 0.115), suggesting reduced recharge efficiency. These findings highlight the need for region-specific groundwater management measures, such as adaptive irrigation scheduling and crop diversification, to sustain agriculture under growing groundwater stress.