Spatio-Temporal Variation and Seasonal Rainfall Trends Across Agro-Climatic Zones of Himachal Pradesh (1981–2024) and Their Implications for Maize and Wheat Yields

Understanding long-term precipitation variability and its agricultural implications is essential for climate-sensitive mountain regions. This study investigates spatial and seasonal precipitation trends across the agro-climatic zones of Himachal Pradesh using long-term gridded rainfall data from the NASA POWER database (1981–2024). Monthly precipitation was aggregated into annual and seasonal series (winter, pre-monsoon, monsoon, and post-monsoon). Trends were detected using the Modified Mann–Kendall test and Sen’s slope estimator, while spatial patterns were represented using Inverse Distance Weighting interpolation. The results indicate a consistent increasing trend of precipitation across the state, with monsoon rainfall contributing the largest share of the observed increase. The winter precipitation also showed rising trend in higher elevation regions influenced by Western Disturbances. To evaluate agricultural implications, maize (kharif) and wheat (rabi) yields were analysed in relation to seasonal rainfall using Pearson correlation. The results reveal that maize productivity is more responsive to monsoon rainfall, whereas wheat yield shows stronger dependence on winter precipitation. These findings highlight spatially differentiated climate sensitivity of crops and provide insights for climate-responsive agricultural planning in the western Himalayan region.