1960～2012年期间湖南省及周边地区气温变化趋势分析

Analysis of air temperature change in the vicinity of Hunan between 1960 and 2012

结合Mann-Kendall和线性回归方法,对湖南省及周边地区46个国家气象站1960~2012年期间日平均气温(T_(mean)),日最高气温(T_(max)),日最低气温(T_(min))和日温差(TDTR)的年平均和季节平均值进行了趋势分析.发现1960~2012年间,T_(mean)、T_(max)和T_(min)总体上呈增加趋势,其中T_(min)增加相对显著,TDTR总体上呈减小趋势.空间上,洞庭湖平原和江汉平原增温速率最大,向南随海拔增高而增温速率减小.1960~2012年期间,各气象站的相关要素多数存在较明显的变点,变点前后的变化趋势存在较大的差异,且发生变点的时间在空间上存在明显的分异规律.研究还发现,各气象站变化趋势的统计平均值与所有站点要素平均值的趋势不一致,原因在于对要素进行平均会造成单个站点趋势信息的丢失,导致结果失真.因此,在气候变化研究中需要合理应用地理统计方法和遥感数据,以获得变化趋势的空间分布规律.

Using Mann- Kendall test and linear regression method, the annual and seasonal trend was analyzed, which of diurnal mean, max, min and range （Tmean, Tmax, Tmin, TDTR for short hereafter） of air temperature between 1960 and 2012 at 46 national meteorological stations in and in the vicinity of Hunan Province. Except TDTR descreased, the series of Tmean, Tmax, and Tmin overall increased over the period between 1960 and 2012, and the Tmin. increased faster. Results show that the air temperature observed at most stations in the Dongting Lake Plain and Jianghan Plain increased fastest and the warming speed decreased with altitude in the south part of the study region. The series of mentioned variables at almost all stations have change point between 1960 and 2012, before and after which the changing trends are different. Compared to the trend of regional mean value of all meteorological stations, the statistics of all single station＇ s trends are much different, because information loss of single station＇s trend is inevitable in the smoothing processes of regional mean. Therefore, introducing remote sensing data and geostatistics are necessary in future study.