[Spatio-temporal variations and influencing factors of thermal comfort at different elevations.]

Thermal comfort is one of the ways assessing heat changes in climate change scenarios. Based on the daily observation data of 84 meteorological stations from Guizhou Province, the universal thermal climate index (UTCI) was used to examine the spatio-temporal variations and main influencing factors of thermal comfort at different elevations under the scenarios of climate change. Moreover, the impacts of different climatic factors on UTCI at different elevations were quantitatively analyzed. The results showed that the spatial distribution of annual UTCI in Guizhou Province had a strong consistency with that of annual temperature, which was decreasing with the increased elevation. The number of thermally comfortable days in most parts of the province was between 180 d and 240 d. UTCI increased with the increases of elevation, with the overall trends of UTCI [-0.58-1.38 ℃·(10 a)^-1] being higher than the trends of temperature [-0.36-0.45 ℃·(10 a)^-1] from 1984 to 2013. In general, the correlation coefficients between UTCI and climatic factors air tempe-rature, wind speed, atmosphere pressure, relative humidity and cloud cover were 0.899, -0.855, 0.818, -0.373, and -0.042, respectively. The correlations between climatic factors and UTCI varied across different elevations. The UTCI was affected lightly by air temperature and heavily by wind speed with increasing elevation.