气候舒适度在不同海拔的时空变化特征及其影响因素

气候舒适度是在气候变化背景下评估热量变化的方式之一.本研究基于1984-2013年间贵州省84个气象台站的逐日观测数据,采用通用热气候指数(UTCI)讨论不同海拔的气候舒适度时空变化规律及主要影响因子,定量分析了不同海拔地区各气候因子对UTCI的影响差异.结果表明: 1984-2013年间,贵州省多年平均UTCI与气温在空间分布格局上有很强的一致性,均表现为温度随海拔升高而降低,全省大部分地区年舒适天数在180～240 d之间;贵州省各站点UTCI增幅随海拔升高而增大,且UTCI变化幅度[-0.58～1.38 ℃·(10 a)^-1]高于气温变化幅度[-0.36～0.45 ℃·(10 a)^-1];在全省范围内,UTCI与各气候因子的相关关系由大至小依次为气温、风速、气压、相对湿度和云量,相关系数分别为0.899、-0.855、0.818、-0.373和-0.042;在不同海拔地区,不同因子与UTCI的相关系数变化有很大的不一致性.随海拔升高,UTCI受气温影响逐渐减弱,风速的影响程度增大.

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.