Impact of Climate Variability on Green Gram in Prayagraj, Uttar Pradesh, India

Abstract

This study examines the climatic trends and their relationship with green gram yield in the Prayagraj region over the period 1992–2024. Long-term analysis of meteorological data revealed distinct seasonal patterns and significant shifts in temperature, rainfall, and humidity. The annual mean maximum temperature (33.51 °C) showed a statistically significant decreasing trend, particularly during winter, with the strongest declines in December and January. In contrast, the annual mean minimum temperature (21.46 °C) exhibited a slight increasing tendency, with significant warming in September and October, indicating a narrowing diurnal temperature range. Rainfall patterns were highly seasonal, with over 80 % of precipitation concentrated in the monsoon months. Trend analysis indicated a gradual increase in annual and monsoonal rainfall, particularly in June, July, and May, while winter and post-monsoon rainfall declined. Relative humidity displayed a consistent and statistically significant upward trend annually and across most seasons, with the highest increases during winter and post-monsoon periods. Correlation analysis between weather parameters and green gram yield highlighted stage-specific sensitivities. Excessive maximum temperatures during pod development, especially in SMW 33, significantly reduced yields, whereas adequate rainfall during flowering (SMW 30) and higher relative humidity during both pod development and early harvest positively influenced productivity. These findings suggest that climate variability in Prayagraj is characterized by cooler days, warmer nights, rising humidity, and shifting rainfall distribution, all of which have critical implications for crop management. The study underscores the need for adaptive agricultural strategies tailored to phenological stages to mitigate adverse climatic effects and sustain green gram yields under changing climate conditions.