Abstract
Rainfall significantly influences climatic conditions and agricultural productivity, particularly in arid ecosystems dependent on rainfed agriculture. This study analyzes monsoon precipitation and its extreme events at an intraseasonal level from 1981 to 2021 in the Western Plains (WP) and Kachchh Peninsula (KP) Agroecological Region (WK AER), primarily encompassing the Kachchh district of Gujarat, the western part of Rajasthan, and the southwestern regions of Haryana and Punjab in northwestern India. The analysis also examines their subsequent responses to Kharif crops across this region. Gridded precipitation datasets from the India Meteorological Department (IMD) (0.25° × 0.25°) and crop productivity data from the Directorate of Economics and Statistics, Ministry of Agriculture and Farmers Welfare, Government of India, were utilized. Trends from 1981 to 2021 were analyzed using Mann-Kendall (MK), Sen Slope Estimator, and Innovative Trend Analysis (ITA) for each month (June, July, August, and September) and the entire monsoon season. The ITA was exclusively used to assess extremes in rainfall trends as the Sen Slope was found to be ineffective in these instances. Furthermore, the correlation between rainfall extremes and crop productivity (bajra, cotton, groundnut, moong) was examined using Spearman’s rank correlation. Results indicate increased rainfall during June, August, September, and the overall monsoon season, with spatial variations captured through grid-wise analysis. Rainfall and its extremes have notably risen over the Kachchh Peninsula. A positive trend was observed in June, September, and across the monsoon season, except in central and southwestern WP. The July trend declined throughout WP, contrasting with eastern and northeastern WP. The northern WP observed negative ITA values, while the rest of the WP showed positive trends increasing southwards in August. The study highlights the dominance of intraseasonal extremes in shaping regional rainfall patterns, with varying impacts on agricultural productivity. Notably, a low positive correlation exists between monsoon rainfall and crop productivity, with negative correlations observed in Jhunjhunu and Kachchh during August. The results underscore the potential for targeted interventions to enhance agricultural outputs in response to favorable monsoon variations in arid regions, contributing to economic strategies aimed at doubling farmers' incomes.