A high-resolution air temperature data set for the Chinese Tianshan Mountains in 1979-2016

The Chinese Tianshan Mountains (CTM) has a complex ecological environment system. It not only has a large number of desert oases, but also gave birth to a large number of glaciers. The arid climate and the shortage of water resources are the important factors to restrict the socio-economic development in this area. This study presents a unique high-resolution (1km, 6h) air temperature data set for the Chinese Tianshan Mountains from 1979 to 2016 based on a robust statistical downscaling framework. The coverage of data set is 41.1814-45.9945 °N, 77.3484-96.9989 °E. The grid point is derived from SRTM DEM, which is resampled from 90m to 1km. The total number of grid point is 818126. The time step is 6 hour at 00, 06, 12, and 18 Uhr. The data set was validated by 24 meteorological stations at daily scale. Compared with undownscaled ERA-Interim temperature, the Nash-Sutcliffe efficiency coefficient (NSE) increased from 0.90 to 0.94 over all test sites. Around 24% of root-mean-square error (RMSE) was reduced from 3.75 to 2.85 °C. A skill score based on the probability density function (PDF), which was used to validate the reliability of the new data set for capturing the distributions, enhanced from 0.86 to 0.91 for all test sites. We conclude that the new high-resolution data set is reliable for climate change investigation over the Chinese Tianshan Mountains. This data set would be helpful for the potential users for better local climate monitoring, modelling and environmental studies in the Chinese Tianshan Mountains.