Sichuan province is one of the 13 major grain-producing provinces in China and also an obvious region of climate change. In this study we investigated the response of maize yield to climate variables under climate change based on yield observations and climate data at 92 counties in Sichuan province of China from 1981 to 2012. The results indicated that change of climate variables, i.e. increase of average temperature and diurnal temperature range, and decrease of precipitation and solar radiation, during different development stages in recent 30 years caused significant change of yields in around 30% of the maize planting area. Increasing average air temperature showed a significant effect on yield in 27.3%, 10.9%, 15.2% and 9.9% of maize growing area during RGS (From sowing to maturity), RGS1(From sowing to jointing), RGS2(From jointing to milk) and RGS3(From milk to maturity), respectively. Per centigrade degree increase in diurnal temperature range showed a significant effect on yields in 28.0%, 29.5%, 17.9% and 9.9% of the maize area during RGS, RGS1, RGS2 and RGS3, respectively. Per 100-mm decrease in precipitation showed a significant effect on yields in 16.4%, 11.1%, 12.8% and 3.1% of the maize area during RGS, RGS1, RGS2 and RGS3, respectively. Per 100-MJ m−2 decrease in radiation showed a significant effect on yields in roughly 14.2%, 26.1%, 10.6% and 8.7% of the maize area during RGS, RGS1, RGS2 and RGS3, respectively. Climate change from 1981 to 2012 had caused significant impacts on maize yields in 68.3% of the maize area, most of which showed negative effects, and maize yields changed by −25.8 to 13.9%. Moreover, average air temperature was the key contributor that affecting maize yields. Increase of average air temperature caused a significant decrease of yield in 20.1% of the maize area. These empirical findings provide a foundation for anticipating climate change impacts on maize production.
