Supporting Text

The Chinese observed land-surface air temperature data set includes measurements from 731 meteorological stations from 1951 to the present, as collected and processed by the National Meteorological Center of the China Meteorological Administration (1, 2). Because some stations were removed, the actual total number of stations in operation today is 671, distributed among 31 provinces and municipalities. Fig. 6 shows the district map of these provinces and municipalities, and Fig. 7 shows the location and topography of these stations. In this study, we use the monthly mean daily maximum and minimum temperature data (1) from the 610 stations that have a complete set of observations for the period from January 1979 to December 1998.