采用4种不同的地表特征因子及其组合,使用三层分解模型对研究区地表温度进行降尺度实验。实验结果表明:1)使用多地表特征因子组合的三层分解模型获得的降尺度精度高于使用单因子获得的降尺度精度,均方根误差由0.813 K提高到0.763 K,降尺度结果的误差主要集中在建筑区域;2)采用热场强度指数和热场变异指数作为评价指标,研究城市热岛效应,两种评价指标均表明多因子模型的精度优于单因子模型的精度。

A three-layer decomposition model is used to downscale the surface temperature of the study area via four different surface feature factors and their combinations. Experimental results show that the three-layer decomposition model using multi-surface feature factor combination obtains higher downscaling accuracy than that using a single factor, and the root mean square error increases from 0.813 K to 0.763 K; the main source of error is the architectural area. To study the urban heat island effect, this study uses the heat field intensity index and heat field variation index for evaluation; both evaluation indexes indicate that the accuracy of the multi-factor model is better than that of the single factor model.