ESTIMATION OF SUMMER SURFACE URBAN HEAT ISLAND OF NOVOSIBIRSK FROM LANDSAT 8 SATELLITE IMAGES

Abstract

An urban heat island is a phenomenon which occurs when the temperature in urban areas is higher than that in their rural surroundings. The formation of an urban heat island has a negative impact on the health of urban dwellers and the ecology of the city. We assessed the intensity of the surface urban heat island (UHISurf) in the city of Novosibirsk during the summer period from 2018 to 2020 using two categories of indicators – those based solely on differences in temperature (UHI-driven) and those including land cover type data (land-cover-driven). Data from the Landsat 8 were used to obtain information on land surface temperature. In accordance with the chosen methodology, bands 4, 5 and 10 were taken to calculate the land surface temperature. A prerequisite for satellite data selection was the absence of cloud cover over the study area. In this paper, nine buffers with a diameter of 1 km were selected, each around ground-based meteorological observation points at the Roshydromet network of stations. The results obtained indicate the presence of a stable surface urban heat island in Novosibirsk during the study period. The maximum value among all surface urban heat island intensity indicators was 23,0°C for the range indicator. Negative intensity values (up to –1,6°C) were also obtained for several cases, which is associated with a larger heating of croplands relative to urban surfaces. It is concluded that UHISurf intensity values depend on the choice of the calculation approach.