Changes in climate extremes and their impact on wheat yield in Tianshan Mountains region, northwest China

Investigating the relationships between climate extremes and yield can help understand how unfavorable climatic conditions affect crop production. In this study, spatiotemporal patterns of extreme climate events and their impact on wheat yield were investigated in the Tianshan Mountains region (TMR) using meteorological and agricultural data. The modified Mann–Kendall test and Pettitt test were employed to detect trends and abrupt changes in the climate patterns, and the first-differences technique and Pearson’s correlation test were used to analyze the climate extremes–wheat yield relationships. The main results were as follows: (1) a significant warming and wetting tendency occurred in TMR during 1961–2013, with more stations manifesting larger trend magnitudes of extreme climate indices; (2) although three subregions also exhibited a consistent trend of temperature and precipitation, warming rates were the highest in the eastern TMR and wetting trends were the largest in the northern slope of TMR; (3) 15 stations showed significant correlations between wheat yield and extreme temperature or precipitation indices. In precipitation-sensitive regions, greater rainfall was beneficial to the yield. In temperature-sensitive regions, while an increase in higher temperatures and night warm extremes were unfavorable for the yield, a decrease in cold extremes could help increase the same.