An Analysis of the Spatiotemporal Distribution of Impervious Surface and Land Surface Temperature in Plateau Areas

As an important city in the plateau areas, Lhasa has a significant impact on the vulnerable area due to the change in the impervious surface and the temperature variation resulting from the change. Therefore, Lhasa, including the urban area and the suburbs, was selected as an experimental area. Impervious surface coverage (ISC) and land surface temperature in the experimental area were estimated respectively with the linear spectral mixture analysis and atmospheric correction. Contribution index (CI) to the urban thermal environment, combined with the ISC and land surface temperature data over the past decade (2009-2018) were used to discuss the relationship between ISC and land surface temperature in terms of spatiotemporal distribution with the purpose of providing help for long-term monitoring of basic ecological change in plateau areas. The results show that, due to seasonal variations, the response of land surface temperature to ISC has two patterns. The areas with ISC ranging from 0 to 0.1 have positive contributions to the urban thermal environment while the areas with ISC greater than or equal to 0.1 have negative contributions in winter. The areas with ISC ranging from 0 to 0.1 have negative contributions to the urban thermal environment while the areas with ISC greater than or equal to 0.1 have positive contributions in summer. In winter, the relationship between ISC and CI shows a negative correlation. In summer, CI shows a declining trend at ISC < 0.5 and a rising trend at ISC≥0.5. With the increase of ISC, land surface temperature decreases slightly in winter. The influence of ISC on land surface temperature shows a V-shape tendency in summer.