Temperature and precipitation are adversely affecting wheat yield in India

Abstract

An understanding of the climate-crop yield relationship has remained elusive. Wheat is one of the essential food crops globally. India is the second-largest wheat producer. Herein, we evaluate 50 years of detailed climate and wheat crop statistics (1966–2015) to spatially analyze temperature and precipitation trends and their impact on wheat yield across 29 Indian states using statistical methods. Temperature and precipitation are refined for seasonal (Rabi season), annual, and monthly durations at the state level because state is the administrative unit in India for adaptation strategies and mitigation purposes. We find that temperature has been increasing (statistically significantly) across all the Indian states, whereas precipitation change has been statistically non-significant. The seasonal temperature has harmed ∼99.85% of India's wheat harvested area (i.e., ∼24.1 million hectares, 21 Indian states). Seasonal precipitation has harmed ∼56.26% of the wheat harvested area (i.e., ∼13.6 million hectares, eight Indian states). February temperature and March precipitation demonstrate the most adverse impact on wheat yield. Climate variability explains up to ∼78% wheat yield variability across Indian states. These results help identify the effects of changing climate on wheat yield and thus demand immediate attention and a response plan to develop adaptation strategies to address climate change. HIGHLIGHTS Temperature and precipitation trends are investigated using parametric and non-parametric methods.; Results demonstrate statistically significant rise in Rabi season and annual temperatures across India.; Twenty-one Indian states demonstrate negative correlation between Rabi temperature and wheat yield.; Temperature and precipitation variables explain up to ∼78% of wheat yield variability across Indian states.;

Keywords

• climate change
• india
• precipitation trends
• temperature trends
• wheat yield