Extraction of urban impervious surface using two-season worldview-2 images: A comparison

Although multispectral images acquired during the summer season have been used extensively in impervious surface extraction with relatively high accuracy, the area of impervious surface extracted is generally underestimated. In this study, a quantitative comparison of urban impervious surface extraction was conducted using WorldView-2 images of the summer and winter seasons over two urban areas in a temperate region of Northern China. A hierarchical object-based classification method was adopted to extract urban impervious surfaces. The results showed that the impervious surface extraction from the winter image achieved an accuracy comparable with that from the summer image. However, the area of impervious surface extracted from the winter image was much greater than that from the summer image, which was mainly attributed to seasonal variations of deciduous trees. Therefore, winter images are recommended for impervious surface mapping in temperate regions using very high resolution images.