Spatiotemporal change and non-stationarity of air temperature in China from 1959 to 2018

•China's temperature increased by 0.995℃ in 1959-2018, warming was more severe in 1989-2018.•Temperature rises were higher in northwest, east coast, northeast areas.•Warming trends were more severe in urban agglomerations.•A new framework was used to test temperature non-stationarity based on autocorrelation test model.•China's temperature change showed non-stationarity in 1959-2018.