Abstract:Based on the monthly reports of the maximum and minimum temperatures recorded by instruments since the establishment of the Guiyang National Reference Meteorological Station on 5 September 1920, the sequences of the maximum and minimum temperatures and the diurnal temperature ranges over the past century in Guiyang are established. Through multiple verification methods of the sequences, it has been found that the minimum temperature and the diurnal temperature ranges from 1938 to 1944 had significant differences from the mean value of the sequences, with breakpoints in the sequences appearing in 1937, 1944 and 2000. According to the historical evolution, observation record books and weather report stubs, as well as the comparison of multi source and multi station data, the minimum and maximum temperatures from 1938 to 1944 in the reports are found to be inaccurate, thus the data for this period are replaced with the records from the observation record books. Using the mean values of daily maximum and minimum temperatures and the daily temperature differences in 1938-1949, a conversion and correction scale is established to construct the daily temperatures for the period from 1921 to 1936 when temperature records are missing. The non uniformity of temperature caused by station relocation is revised recursively by using the initial values of this station and the annual changes of the optimal reference station. The finally established homogenized temperature series of Guiyang over the past century shows a good consistency with the global temperature changes during the corresponding period. The results show that over the past century, the temperature in Guiyang has experienced two relatively significant “warming” stages, one from 1937 to 1953 and the other one since 1978. In the second warming stage, temperature rise was accelerated in 1996 and changed abruptly in 2011. The tendency rate of temperature change in Guiyang over the past century is 0.12℃ to 0.14℃ per decade, and the minimum temperature has been oscillating upward since 1929, warming up with a tendency rate of 0.26℃ to 0.31℃ per decade. The diurnal temperature ranges have been declining with a tendency rate of -0.29℃ to -0.27℃ per decade. There is no obvious trend variation in maximum temperature. The warming rates of temperature and minimum temperature in autumn and winter are higher than those in spring and summer. February is the month with warming, the most, while July is the month seeing warming, the least. The warming is mainly caused by the increase in minimum temperature.